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BACKGROUND OF THE INVENTION
The invention relates to novel thermoplastic block copolymers that can be produced by condensation polymerization and that consist of poly(meth)acrylate and polyamide segments, to their production, and to the use thereof. The inventive block copolymers exhibit a unique combination of the characteristics of poly(meth)acrylates (PMMA) and polyamides, can be used as modifying agents both in polyamide and in poly(meth)acrylates, and act as compatibility promoters in blends or are tailor-made adhesion promoters in multilayer systems such as multilayer polymer pipes.
Polyamides are among the most important technical thermoplastics, with diverse applications in a wide variety of fields. This versatility results from the fact that polyamides are modifiable in manifold ways, which makes it possible to produce tailor-made products. Copolymer formation, besides its utility for introducing reinforcing and filling agents, blending with other polymers, and adding various additives, is an important means of purposefully influencing the characteristics of polyamides. The linear block polymers that are known from the literature are primarily those containing segments based on polyethers, polyesters, polysiloxanes, polyimides and polycarbonates, besides the polyamide segment (J. Stehlicek, J. Horsky, J. Roda, A. Moucha in “Lactam based Polyamides” Vol. 2, R. Puffr, V. Kubanek, Ed., CRC Press, Boca Raton 1991, 20ff). But few examples can be found of the combination of polyamides and segments based on vinyl monomers. One exception is block copolymers consisting of polyamide 6 and polystyrol, poly(butadiene co-acrylic nitrile)(Colloid Polym. Sci. (1989), 267(1), 9-15), poly(styrol co-butadiene), polybutadiene and polyisobutylene.
Hitherto, block copolymers consisting of polyamide and poly(meth)acrylate segments have been obtainable from high-molecular (i.e. oligomeric) polyamides only by means of radical polymerization of macromolecular initiators. The synthesis of these initiators from polyamide pre-condensers, usually furnished with amino end groups, is carried out either by conversion with suitably functionalized low-molecular azo or peroxo initiators (Polymer Journal 31 (10), 864-871), or by nitrosation of a commercial polyamide and subsequent photochemical rearranging in the corresponding high-molecular diazoester (J. Polym. Sci., Polym. Chem. Ed. (1980), 18(6), 2011-20; J. Polym. Sci., Polym. Chem. Ed. (1982), 20(7), 1935-9). It is thus possible to produce AB, ABA or, by nitrosation, segmented multiblock copolymers by thermally or photochemically induced radical mass polymerization or solution polymerization.
With the photochemically or thermally induced decomposition of the diazoester, biradicals usually emerge, which give rise to branchings and cross-linkings. Many of the products are thus rubbery and insoluble. The formation of graft polymers is unavoidable owing to the high transfer rate. Furthermore, the characteristics of these copolymers are determined almost completely by the vinyl components. The yield of conversion with MMA (methylmethacrylate) is insufficient. Whereas a nearly total conversion occurs for the reaction pair of polyamide 6/acrylic nitrile (or vinyl acetate), the conversion is only 25% for MMA.
In the case of polyamide oligomers with azo end groups, only AB or ABA block copolymers are obtainable. The conversions must be carried out in solution. The initiator effectiveness is very low, so that inconsistent products are formed. Owing to the required reaction procedure, limitations in the concentration, segment length, and composition of the polyamide precondensate can be expected, because these parameters directly determine the dissolving behavior of the components and determine the solution viscosity of the reaction mixture.
The polycondensation of a polymethacrylate macromonomer with polyamide generating monomers for producing graft copolymers was described for the first time by Y. Yamashita in Polymer Bulletin 5 (361-366). The PMMA macromonomer was obtained by the radical polymerization of MMA in the presence of thio amber acid as the chain transfer agent. The generating of the polyamide backbone was accomplished by catalyzed polycondensation with aromatic diamines and aliphatic dicarboxylic acids in solution.
Besides this, Y. Chujo et al. describes the use of 2-mercaptoethanol and 2-aminoethane thiol as the chain transfer agent for functionalizing PMMA oligomers in J. Polym. Sci., Part A: Polymer Chemistry 27, 2007-14 (1989). The generated monofunctional PMMA oligomers are converted into the corresponding PMMA dicarboxylic acid by subsequent reaction with trimellitic acid anhydride. Macromonomers are thus available for the polycondensation. The resulting copolymers are graft copolymers with a polyamide main chain and PMMA side chains.
By preforming the PMMA macromers, it is possible to avoid the complications that arise in the radical polymerization; however, the building of the aforementioned polyamide chains must also be performed in solution. But the use of the a-bifunctional macromers only makes possible the synthesis of graft copolymers.
Thermoplastic polyamide blends consisting of polyamide 6 and anionically produced block polymers based on polyamide 6 are described in U.S. Pat. No. 4,501,861. The oligomeric diols used there, which include poly(alkylacrylate), must be converted on both ends of the chain with an acyl lactam unit, in order to make possible incorporation during the anionic polymerization of capro lactam.
The anionic ring opening is limited to lactams and requires a high purity of the utilized components, particularly absolute anhydrousness. The diols must also be fully refunctionalized; otherwise, break-off centers for the anionic polymerization will be created, which result in a high residual lactam content and a low polymerization grade. Reproducibility is therefore a primary problem of this process as well.
SUMMARY OF THE INVENTION
It is thus an advantage of the invention to make available new polyamide polyalkyl(meth)acrylate block copolymers which avoid the abovementioned disadvantages of the prior art and can be produced by polycondensation.
The invention relates to polyamide polyalkyl(meth)acrylate block copolymers which are built from conventional polyamide generating monomers in addition to 15-70 weight percent polyalkyl(meth)acrylates.
The inventive block copolymers are produced by producing polyamide or copolyamide blocks with an average molar mass in the range between 500 and 5,000 g/Mol, preferably between 750 and 2,500 g/Mol, with an amino end group concentration of at most 50 mMol/kg, in a first polymerization or polycondensation step at temperatures between 180° and 300° C., a pressure between atmospheric pressure and 3×106 Pas (30 bars), potentially with the addition of component D provided that X═N in Formula (III), and degassing at least 0.5 hours at a pressure between 50 mbar and atmospheric pressure in order to reduce the water content; adding, in a second step, α,ω-functionalized polyalkyl(meth)acrylate diols with an average molar mass in the range between 600 and 5,000 g/Mol, preferably in the range between 900 and 2,500 g/Mol, as a solid substance, solution, or fusion [or: melt] with all or part of the diol component (III) provided that X═O in Formula (III), or, provided that X═O, converting component (III) into the DMMP polyester diol with the aid of the PMMA diol in a parallel condensation step; and fully condensing the reaction mixture into high-molecular block copolymer (A) in the presence of between 0.05 and 0.2 weight percent a catalyst at a temperature between 180° and 300° C. at a reduced pressure in a further polycondensation step; discharging it, or further processing it into molding bodies.
The invention also relates to thermoplastic multilayer compounds consisting of at least one layer of a molding material based on (co)polyamide, at least one layer of a molding material consisting of a thermoplastic material from the group consisting of polyalkyl(meth)acrylates, polycarbonates, or blends of polycarbonates with other plastics such as polyolefins, whereby the polyalkyl(meth)acrylates are homopolymers or copolymers wherein up to 50 Mol % of the methyl(meth)acrylate can be replaced by other monomers from the group consisting of butylmethacrylate, butylacrylate, methacrylic acid, itaconic acid, styrol, and maleic acid anhydride, the fluoropolymers or the perfluoridated polymers or mixtures of these compounds; and at least one intermediate layer based on an adhesion promoter molding material from the thermoplastic block copolymers. According to the invention, an alternative option for the adhesion promoting intermediate layer between layers (a) and (b) is a blend of the polymers that constitute layers (a) and (b), whereby at least one part of the blend can consist of the thermoplastic block copolymers. In a separate embodiment of the invention, the physical mixture (blend) contains at least 8% of the inventive thermoplastic block copolymers by weight. In another embodiment, the intermediate layer based on an adhesion promoting molding material can consist, up to 100 weight percent, of the thermoplastic block copolymers.
The inventive multilayer compounds can be utilized as structural components primarily in the automotive, electronics, and mechanical engineering industries. In particular, they can be utilized in the fabrication of fibers, films, molded bodies such as housings, housing parts of mobile radiotelephones, and as hot-melt adhesive. Their utilization as a multilayer pipe in the automotive field is particularly advantageous.
The invention also relates to multilayer polymer tubing or piping, which can also be corrugated in at least one subregion, consisting of an inner layer of fluoropolymers, an outer layer of polyamide, preferably polyamide 12 or polyamide 12 derivatives, and an intermediate adhesion promotion layer based on the thermoplastic block copolymers claimed in one of the claims 1 to 6 . But a physical blend of the polymers forming the inner and outer layers can also be provided as an adhesion promoting layer, whereby at least one part can be replaced by the thermoplastic block copolymers claimed in one of the claims 1 to 6 . This physical blend advantageously contains 8% of the inventive thermoplastic block copolymers by weight. Alternatively, 100% of the intermediate layer can consist of the thermoplastic copolymers.
The fluoropolymers which are utilized for the inner layer of the inventive multilayer polymer tubing or piping are selected from fluoropolymers based on tetrafluoroethylene (TFE), hexafluoropropylene (HFP) and vinylidene fluoride (VDF) and fluoropolymers based on tetrafluoroethylene (TFE), perfluoromethylvinylether (PMVE) and vinylidene fluoride (VDF). A terpolymer from tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride (trade name: THV 500 G, manuf: 3M) is particularly preferred. An inner layer of PVDF is highly preferred.
Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the figures.
DETAILED DESCRIPTION OF THE INVENTION
Polyamide Portion
Any conventional lactam, aminocarboxylic acid, dicarboxylic acid, or diamine pair can be used as the polyamide-building monomers. The monomers that are suitable building blocks for the polyamide segments come from the class of lactams having 6-12 C-atoms, for instance lauric lactam or the corresponding α, ω amino carboxylic acids with 6-12 C atoms, such as ω-aminolauric acid or the combination of aliphatic diamines with 2-12 C atoms and dicarboxylic acids with 2-44 C atoms and aliphatic and cycloaliphatic diamines with 2-18 C atoms such as dodecane diamine/dodecanoic diacid or dodecane diamine/sebacinic acid or dodecane diamine/C36 dimeric acid, and on the other hand, other monomers which are used for semi-aromatic polyamides. The polyamide component of the inventive block copolymers is preferably based on the following:
1) aliphatic homopolyamides such as PA 46, PA 6, PA 66, PA 69, PA 610, PA 612, PA 636, PA 810, PA 1010, PA 1012, PA 11, PA 12, PA 1212, or semi-aromatic polyamides such as PA 6I, PA 6T, PA 6I6T, PA 9T, PA 12T, as well as copolyamides and multipolyamides based on the dicarboxylic acids C 2 -C 36 and diamines C 2 -C 24 as well as lactam 6, lactam 12, isophthalic acid, terephthalic acid, and naphthalinedicarboxylic acid. The polyamide component can also be obtained by polycondensation of the corresponding salt of diamine and dicarboxylic acid.
For example, in an embodiment of the present invention, a polyamide dicarboxylic acid of the general formula HOOC—B—COOH is present. The polyamide dicarboxylic acid of this embodiment may be according to the Formula (IIa) or (IIb):
wherein a is a whole number from 5 to 11 and b is a whole number from 2 to 50,
or
wherein b is a whole number from 2 to 40. In Formulae IIa or IIb, R 7 is selected from the group consisting of a bivalent aliphatic unsaturated hydrocarbon residue with 2-20 carbon atoms, a cycloaliphatic hydrocarbon with up to 36 C atoms, and an aliphatic aromatic hydrocarbon residue with 8-20 C atoms. Further, R 8 is selected from the group consisting of a bifunctional aliphatic hydrocarbon residue with 2-12 C atoms, a cycloaliphatic hydrocarbon residue with 6-20 C atoms, an aliphatic aromatic hydrocarbon residue with 8-20 C atoms and a bivalent aliphatic ether residue —R 6 —O—R 6′ —, whose residues R 6 and R 6′ together have 4-20 C atoms.
2) amorphous polyamides or copolyamides which are built from branched or unbranched aliphatic diamines with 6-18 C atoms, such as 1,6-hexamethylenediamine, 2,2,4- or 2,4,4-trimethylhexamethylenediamine, cycloaliphatic diamines, such as 4,4′ diamino-dicyclo-hexylmethane, 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, isophoronic diamine or aromatic diamines with 6-12 C atoms, such as m and p xylylenediamine and aliphatic, cycloaliphatic, or aromatic dicarboxylic acids with 6-12 C atoms.
3. Other possible polyamide-building polymers include transparent copolyamides with a glass temperature of 30-130° C., which are built from 90-45 weight percent lauric lactam which can be replaced by o-aminocarboxylic acids with 9-12 C atoms or by aliphatic diamines with 9-12 C atoms in combination with aliphatic dicarboxylic acids with 9-12 C atoms and 55-10 weight percent other monomers for semi-aromatic polyamides consisting of an aliphatic diamine with 2-12 C atoms in an approximately equimolar ratio to diamine and at least one aromatic dicarboxylic acid, which can be replaced by at most 15 Mol % of another aliphatic dicarboxylic acid with 9-36 C atoms. These types of transparent copolyamides are described in EP 603 813 B1.
The inventive polyamide segments have average molar masses in the range between 500 and 5,000 g/mol, preferably in the range between 750-2,500 g/mol.
PMMA Portion
The polyalkyl(meth)acrylate segment for the inventive block copolymers that are obtainable by polycondensation is incorporated in the form of a α,ω-functionalized polyalkyl(meth)acrylate which carries end groups that are capable of condensation. These include α,ω-poly(meth)acrylate diols which are produced according to what is known as the “Iniferter technique” (C. P. Reghunadhan Nair et al. in J. Polymer Sci., Part A: Polymer Chemistry 27, 1795 (1989)), or those produced according to DE-A-43 14 111 or U.S. Pat. No. 5,900,464, or the α,ω poly(meth)acrylate dicarboxylic acids described in EP-A-0 708 115.
In an embodiment, these poly(meth)acrylate diols are present in the general formula HO—A—OH, or more particularly according to Formula I:
wherein z is a whole number from 4 to 50. In the formula, R 1 is selected from the group consisting of —S—R 5 —OH, —C(C 6 H 5 ) 2 —R 5 —OH, -and S—C(S)—N(C 2 H 5 )C 2 H 4 —OH, R 2 is H,CH 3 , R 3 is an alkyl residue with 1-12 C atoms, which can be halogenated. R 4 is a residue selected from the group consisting of (1), (2), and (3):
(1) —R 5 —OH (2) —S—C(S)—N(C 2 H 5 )C 2 H 4 —OH, (3) —CH 2 —CHR 2 —CO—O—R 5 —OH,
wherein R 5 is a residue selected from the group consisting of (4), (5) and (6):
(4) a bivalent aliphatic hydrocarbon residue with 2 to 20 C atoms, a cycloaliphatic hydrocarbon residue with up to 36 C atoms or an aliphatic aromatic hydrocarbon residue with 8 to 20 C atoms,
(5) a bivalent aliphatic ether residue —R 6 —O—R 6′ , whose residues —R 6 and R 6′ together have 4-20 C atoms,
(6) a bivalent polyether residue according to the general formula —(C n H 2n O) m —C p H 2p , where n=2-4, m≧1, and p=2-4, and the poly(meth)acrylate (I) is partly or completely imidized.
The α,ω-functionalized polyalkyl(meth)acrylates that are utilized have average molar masses in the range between 600 and 5,000 g/mol, preferably in the range between 900 and 2,500 g/mol. The bifunctionality is at least 90%. The glass transition temperature is between −50 and +170° C.
Components A and B
In an embodiment, A and B are replacement characters that are utilized in the thermoplastic block copolymers of the general formula (A) as well as in the formulas HO—A—OH and HOOC—B—COOH, respectively.
Formula HO—A—OH is a simplified representation of Formula I, which describes a poly(meth)acrylate diol. In formula HO—A—OH, both OH groups bonded to A correspond to the alcohol functions of R 1 and R 4 in Formula I. This is further illustrated in the following example.
For an embodiment where:
R 1 =—S—R 5 —OH
R 2 =—CH 3
R 3 =—CH 3
R 4 =(1)=—R 5 —OH
R 5 =(4)=a bivalent aliphatic hydrocarbon residue with 2 C atoms=—CH 2 —CH 2 —
z=4
formula HO—A—OH describing a poly(meth)acrylate diol corresponds to the following formula, in which the replacement character A is identified:
Accordingly, A represents the portion of the above Formula I (after R 1 -R 5 are designated) between the two OH groups. As a result, A can change with the selection of the various R 1 -R 5 constituents. Nevertheless, one having ordinary skill in the art can readily determine what A is, which is contingent on the choices for the R 1 -R 5 constituents.
Formula HOOC—B—COOH is a simplified representation of Formulas (IIa) or (IIb), which describe a polyamide dicarboxylic acid. In formula HOOC—B—COOH, both COOH groups bonded to B correspond to the terminal acid functions in Formulas (IIa) and (IIb), respectively. This is further illustrated in the following example relating to Formula (IIa).
For an embodiment where:
a=5 b=2 R 7 =a bivalent aliphatic hydrocarbon residue with 2 C atoms=—CH 2 —CH 2 — formula HOOC—B—COOH describing a polyamide dicarboxylic acid corresponds to the following formula, which the replacement character B is identified:
Accordingly, B represents the portion of the above Formula (IIa) (after a, b, R 7 and/or R 8 are designated) between the two COOH groups. As a result, B can change with the selection of the various a, b and R 7 constituents. Nevertheless, one having ordinary skill in the art can readily determine what B is, which is contingent on the choices for the a, b and R 7 (and/or R 8 ) constituents.
Component D
a diol or diamine according to Formula (III) is utilized as a further building block of the block copolymers.
HX—D—XH (III), with X═NH or O
where D is selected from the group consisting of (1), (2), (3), (4), (5):
(1) a bivalent aliphatic, potentially cycloaliphatic hydrocarbon residue with 4-36 C atoms, which may be unsaturated as warranted,
(2) an aliphatic olefin polymerisate with a molar mass of 500-4,000 g/mol, unsaturated as warranted,
(3) a bivalent polyether residue according to the general formula —(C n H 2n O) m —C p H 2p , whereby n=2-4, p=2-4 and the molar mass is 400-2,500 g/mol,
(4) a polyester residue according to the general formula (IVa) or (IVb):
where n=a whole number from 3 to 20,
or
where a=a whole number from 5 to 11 and n=a whole number from 5 to 30,
where R 9 is an aliphatic or cycloaliphatic hydrocarbon residue with 2-36 carbon atoms, and
R 7 is a bivalent aliphatic, potentially unsaturated, hydrocarbon residue with 2-20 carbon atoms, a cycloaliphatic hydrocarbon with up to 36 C atoms, or an aliphatic aromatic hydrocarbon residue with 8-20 C atoms;
(5) an organic polysiloxane residue with a molar mass between 500 and 3,000 g/mol.
Examples include butane diol, hexane diol, cyclohexanedimethanol, dodecane diol, dimeric diol, hexamethylenediamine, dodecanediamine, 2,2,4- and 2,4,4-trimethylhexamethylenediamine, 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, 4,4′-diaminodicyclohexylmethane, polyethyleneglycol diol, polypropyleneglycol diol, polytetramethylene diols, polyethyleneglycoldiamines, polypropyleneglycoldiamines, polytetramethylenediamines, polybutadiene diols, and poly(butadienecoethylene)diols, hydrated as warranted, polycaprolactone diols, polyester diols based on aliphatic or aromatic dicarboxylic acids and aliphatic or cycloaliphatic C2-C36 diols or aromatic C6-C18 diols.
Other examples of the substance group (III) HX—D—XH include:
Examples
Average
for Component III
Molar Mass
Functionality
(Component D)
[g/mol]
(XH)
Manufacturer
Kraton Liquid Polymer
3400
OH
Shell
L-2203
Pripol 2033
540
OH
Uniqema
Hycar ATBN 1300x21
2400
NH
BF Goodrich
Tegomer H—Si 2311
2500
OH
Th. Gold-
schmidt AG
Desmophen 2000 MZ
2000
OH
Bayer
Tone Polyol 0230
1250
OH
Union Carbide
Priplast 3197
2000
OH
Uniqema
The first 3 products comprise a pure C chain, while the last 3 examples are copolyester diols. Tegomer H—Si 2311 is a polysiloxane diol.
The invention also relates to the utilization of the block copolymers for producing fibers, films, and molded bodies, for instance of monolayer or multilayer pipes as well as hot-melt adhesives for textiles and technical applications.
It is also possible to use the inventive block copolymers as adhesives for joining housing parts such as housings for mobile radiotelephones. It has long been customary to produce displays for mobile radiotelephones from PMMA, whereas the housing consists of polycarbonate (polycarbonate resins are used for their excellent heat resistance, excellent impact strength, and their good dimensional stability) or ABS. The two parts are then glued together with the aid of glues such as polyurethanes. However, due to increased demand, it is necessary to produce housings from recyclable polyamide materials such as Grilamid TR90. But it has not been possible hitherto to glue such a Grilamid TR90 or polycarbonate housing part to a PMMA display. This is possible for the first time with the aid of the novel inventive block copolymers. A PMMA display can be glued to a housing made of Grilamid TR90 so as to form a splash-proof bond.
The inventive subject matter comprises, among other things, thermoplastic multilayer compounds made of polyamides and polyalkyl(meth)acrylates and polycarbonates and fluoropolymers as well as copolymers and blends based on the cited groups of substances.
The inventive thermoplastic multilayer compound consists of
A: at least one layer of (co)polyamide and
B: at least one layer of a thermoplastic material, selected from the group consisting of polyalkyl(meth)acrylate, the polycarbonate, the fluoropolymer or perfluoridated polymers,
C: at least one adhesion promoter adjoining layers A and B, whereby the layers are joined non-positively, and the block copolymer claimed in one of the claims 1 to 6 is used as adhesion promoter.
Preferred Inventive Embodiments:
1.
Multilayer compound that is produced by injection molding or extrusion, in which the layers A and B are polyamide 12 and PMMA.
2.
Multilayer compound that is produced by injection molding, extrusion, calendering, or sealing, in which the layers (a) and (b) are a transparent polyamide and PMMA or a PMMA copolymer or polycarbonate. The transparent polyamides that are used exhibit a transparency of at least 80% in the wavelength region of visible light. Amorphous polyamides from terephthalic acid and the isomeric blend of 2,2,4- and 2,4,4-trimethylhexamethylenediamine, a copolyamide from isophthalic acid, 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane and lauric lactam, and a polyamide from 1,12-dodecanedicarboxylic acid and 4,4′-diaminodicyclohexylmethane or 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane are particularly preferred.
The layer C between the layers A and B can comprise other functions besides the adhesion promoting action. With the incorporation of UV absorbing, photochromatic, polarizing or thermotropic substances in layer C, the multilayer compound can be utilized as a functional unit in optical applications. It is also imaginable to use a layer that has been functionalized this way as a layer that seals to the inside or the outside. Depending on requirements, adjusting the segment density ratio can instead lend the block copolymer the typical properties of the underlying polyamide, or of P(M)MA.
The scratch resistance of a structural component made of transparent polyamide (PA) can be improved by applying a PMMA outer layer. Conversely, an outer layer of transparent polyamide lends the multilayer compound a good stress resistance and chemical resistance. In either case, a layer that transmits force and promotes adhesion must be used owing to the incompatibility of the polyamide and P(M)MA layers. Utilizing polymethacrylimide (PMI) instead of PMMA makes it possible to realize applications which allow appreciably higher continuous service temperatures. The partial or complete imidisation of the (meth)acrylate component in the block copolymer increases its temperature resistance and appreciably improves compatibility to PMI.
Layer B in embodiments 1) and 2) is composed of polyalkyl(meth)acrylates with 1-12 C atoms in the hydrocarbon chain of the alkyl residue, which may be fully or partly fluorinated. The polyalkyl(meth)acrylates have a melt flow index between 0.5 and 30 g/10 min, measured at 230° C. with a load of 3.8 kg. Polymethylmethacrylate and polybutylmethacrylate are particularly preferred. But copolymers of the polyalkyl(meth)acrylate can also be utilized. Up to 50 Mol % of the methylmethacrylate can be replaced by other monomers such as butylmethacryalte, butlacrylate, methacrylic acid, itaconic acid, styrol, maleic acid anhydride. Polymers that are utilized for layer B can also contain stabilizers, processing aids, impact strength modifiers, fillers, and other common additives in the usual amounts.
3.
Multilayer compound that is produced by injection molding or extrusion, wherein layers A and B are polyamide 12 and PVDF. Owing to the good blocking characteristics of PVDF relative to various fuels, a three-layer pipe with an inner layer of PVDF, a middle layer of the inventive block copolymer, and an outer protective layer based on polyamide 12 can be used in automobiles as a fuel line. The inner layer of the inventive polymer line or tubing is inert with respect to the transported medium; the outer layer is resistant to pressure and mechanical influences. The layer thickness of the inventive tubing or piping is not critical. Preferably, the outer layers are in the range between 0.2 and 0.8 mm; the adhesive layers are in the range between 0.05 and 0.3 mm; and the inner layers are in the range between 0.01 and 0.7 mm. As described above, the wall of the tubing or piping can also be provided with a ring shaped or spiral shaped arch, the inner layers can be furnished with carbon black or carbon fibrils for antistatic protection, and the outer layers can be modified with softeners or other modifiers according to the prior art. Length stability can be achieved by adding glass fibers.
The inventive multilayer polymer lines can be corrugated in one portion, with the rings formed by the corrugations extending around the axis of the piping, whereby the corrugations can be formed at least partly in an oval shape or in the shape of an ellipse or the shape of a circle that is flattened on one side. Such geometries, i.e. the formation of corrugations of piping, are described in DE-A-44 32 584, for example.
The inventive polymer line can be produced by coextrusion of a polymer pipe and subsequently, as warranted, formation of the corrugations including the flattening, if provided, by suction molding or blow molding. But the inventive polymer line can also be produced by extrusion blow molding, coextrusion blow molding, or sequential blow molding with or without tube manipulations.
4.
Multilayer compound that is produced by extrusion wherein a non-positive joint is produced between the cladding of a polymer optical fiber and the adjoining protective sheathe. The at least single-layer protective cladding of the plastic optical fiber waveguide is based on polyamide 12 or polyamide elastomers or polyamide 12 copolymers or blends based on polyamide 12 or thermoplastic polyurethanes, which can also be flame-retardant.
If good overall performance of the wrapped plastic optical fiber waveguide is to be achieved, the core and cladding of the plastic optical fiber waveguide may not soften during the coating process. Any uncontrolled deformation or damaging of the plastic optical fiber waveguide or the cladding unavoidably increases the attenuation, so that the signal range becomes insufficient. Migrating components from the layers adjoining the plastic optical fiber waveguide, which alter the index of refraction of the cladding, must by absolutely avoided, because this adversely affects the total reflection and thus the signal transmission. The block copolymer claimed in claim 1 contains only a very small concentration of residual monomers and no softeners. The adhesion promoting block copolymer claimed in claim 1 can be set such that, despite the relatively low processing temperature, good flow behavior is produced, which leads to a smooth and thin layer which adheres uniformly well to the plastic optical fiber waveguide. Thanks to its unique characteristic, good to very good adhesion values are achieved with the inventive adhesion promoter on nearly all commercial plastic optical fiber waveguides, whose claddings vary widely with respect to chemical composition (PVDF, fluoro copolymers, semi-fluorinated P(M)MAs or (M)MA copolymers, epoxilated polymers). Owing to the variable composition in the polyamide components, very good adhesion is also achieved to various polyamides, PA elastomers and copolymers, PA olefin blends, or polyurethane as the outer or middle layer.
Optical leads of the type described above and the materials utilized are described in WO 00/60382, which is hereby referenced.
The inventively utilized polyamides can also contain stabilizers, processing aids, conventional impact strength promoters, softeners, and other common additives in the usual amounts.
The block copolymers claimed in claim 1 and the molding materials produced therefrom are utilized as adhesion promoters, which make a non-positive joint with the adjacent layers in the fabrication of the multilayer compounds (extrusion, injection molding, sealing). If the polyamide component is suitably selected, the transparency of the multilayer compound is reduced negligibly if at all.
The production of the thermoplastic multilayer compounds can occur in one stage or several stages.
The invention will now be described in several examples, which are not limiting.
EXAMPLE 1
308.45 g aminododecanoic acid, 62.0 g of a polypropyleneglycoldiamine with an average molar mass of 380 g/mol, and 82.25 g adipic acid are condensed into a prepolymer with acid end groups at temperatures up to 260° C. Next, the temperature is reduced to 220° C., and 409.09 g PMMA diol with M n =900 g/mol and 1.00 g monobutylstannic acid are added. Immediately after that, the reactor is sealed, and the pressure is reduced (<10 mbar). After 3.5 h the esterification is ended by breaking the vacuum, and the block polymer is discharged.
EXAMPLE 2
375.55 g aminododecanoic acid, 44.50 g of a polytetrahydrofuranic diamine (M n =950 g/mol) and 57.43 g adipic acid are condensed into a polyetheramide prepolymer at temperatures up to 260° C. The temperature is then reduced to 200° C., and 355.26 g PMMA diol with M n =900 g/mol and 1.00 g monobutylstannic acid are added. The reactor is then immediately sealed, and the pressure is reduced (<10 mbar). After 3.5 h, the esterification is ended by breaking the vacuum, and the bock polymer is discharged.
EXAMPLE 3
4.00 kg lauric lactam are converted into a polyamide 12 precondensate with an average molar mass of 750 g/mol by adding 1.14 kg terephthalic acid and 2.05 kg water at temperatures up to 300° C. and a pressure of 20 bar. After the temperature of the precondensate melt is reduced to 230° C., 3.09 kg of a PMMA diol with an average molar mass of 900 g/mol, 1.88 kg dimeric diol and 14 g monobutylstannic acid are added. Immediately after that, the reactor is sealed, and the pressure is reduced below 10 mbar. After the prescribed torque of 30 Nm is achieved, the esterification is stopped by breaking the vacuum, and the block polymer is discharged.
EXAMPLE 4
Polymerize 5.00 kg lauric lactam, adding 1.00 kg terephthalic acid and 2.40 kg water (pressure phase: 280-300° C., 17-23 bar, 3 h, expansion and degassing at 260° C.). Reduce the temperature to 230° C. and add 2.70 kg PMMA diol with M n =900 g/mol, 1.65 kg dimeric diol and 17 g tetra-n-propylzirconate as 65% solution in n-propanol. Immediately seal the reactor and reduce the pressure (<10 bar). After the desired torque is reached, stop esterification by breaking the vacuum, and discharge and granulate the block polymer.
EXAMPLE 5
Polymerize 6.00 kg lauric lactam, adding 0.75 kg terephthalic acid and 2.70 kg water (pressure phase: 280-300° C. and 17-23 bar, expansion and degassing at 260° C.). Then reduce the temperature to 240° C. and add 2.03 kg PMMA diol with M n =900 g/mol, 1.24 kg dimeric diol and 12 g Metatin S26 (monobutylstannic acid). Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge the block polymer.
EXAMPLE 6
Polymerize 3.78 kg lauric lactam, adding 1.07 kg terephthalic acid and 1.90 kg water (pressure phase: 270-310° C. and 17-23 bar, expansion and degassing at 260° C.). Reduce the temperature to 230° C., and add 4.66 kg PMMA diol with M n =900 g/mol, 0.89 kg dimeric diol, and 17 g tetra-n-butylzirconate in an n-butantol solution. Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge and granulate the block polymer.
EXAMPLE 7
Polymerize 4.00 kg lauric lactam, adding 1.14 kg terephthalic acid and 2.05 kg water (pressure phase: 270-300° C. and 17-20 bar, expansion and degassing at 260° C.). Reduce the temperature to 225° C. and add 4.94 kg PMMA diol with M n =900 g/mol, 0.94 kg dimeric diol and 18 g tetra-n-propylzirconate dissolved in n-propanol. Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge and granulate the block polymer.
EXAMPLE 8
Polymerize 3.60 kg lauric lactam, adding 1.02 kg terephthalic acid (pressure phase: 300° C. and 20 bar, expansion and degassing at 260° C.). Reduce the temperature to 230° C. and add 3.89 kg PMMA diol with M n =900 g/mol, 1.85 kg polybutylmethacrylate diol with M n =1,000 g/mol, 0.17 kg dimeric diol, and 12 g stannic dioctoate. Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge the block polymer.
EXAMPLE 9
Polymerize 4.00 kg lauric lactam, adding 1.14 kg terephthalic acid and 2.05 kg water (pressure phase: 300° C. and 20 bar, expansion and degassing at 260° C.). Reduce the temperature to 230° C. and add 3.39 kg PMMA diol with M n =900 g/mol, 1.88 kg dimeric diol and 17 g n-butylpolytitanate. Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge and granulate the block polymer.
EXAMPLE 10
Condense 389.49 g aminododecanoic acid and 52.46 g adipic acid at temperatures up to 260° C., forming a PA-12 precondensate. Reduce the temperature to 220° C. and add 296.76 g PMMA diol with M n =900 g/mol, 83.45 g polytetrahydrofuranic diol with M n =1,000 g/mol and 1.36 g tetra-n-propylzirconate dissolved in n-propanol. Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge the block polymer.
EXAMPLE 11
Condense amorphous polyamide oligomer with an average molar mass of 2,000 g/mol and an amino end group concentration of 50 mmol/kg, 1.27 kg 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, 1.23 kg dodecanoic diacid and 0.21 kg isophthalic acid into an amorphous PA precondensate at temperatures of 270° C. At the end of the condensation, discharge the condensate and reduce it by means of a crushing machine. The amorphous PA precondensate has a solution viscosity of 1.15 (0.5% in m-cresol) and a glass transition temperature of 120° C.
EXAMPLE 12
Polymerize 460.00 g amorphous PA precondensate from Example 11 with 195.90 g PMMA diol with M n =900 g/mol, 33.30 g polytetramethyleneglycol with an average molar mass of 980 g/mol and 1.20 g of a tetra-n-propylzirconate dissolved in n-propanol under reduced pressure (<10 mbar). After the desired torque is reached, the esterification is stopped by breaking the vacuum, and the block polymer is discharged.
EXAMPLE 13
Convert 2.63 kg 3,3′-dimethyl 4,4′-diaminodicyclohexylmethane, 2.54 kg dodecanoic diacid, and 0.95 kg isophthalic acid into an amorphous PA precondensate at temperatures of 250-280° C. Reduce the temperature to 230° C. and place the precondensate in a melt mixture, which is preheated to 200° C., of 2.58 kg PMMA diol with M n =900 g/mol, 1.57 kg dimeric diol and 24 g of an esterification catalyst. After unifying the components, immediately seal the reactor and reduce the pressure to 5-20 mbar. Upon achieving the desired torque of 30 Nm after 2 hours in the vacuum, stop the esterification by breaking the vacuum, and discharge and granulate the block polymer.
EXAMPLE 14
Convert 2.54 kg 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, 2.46 dodecanoic diacid, and 0.42 kg isophthalic acid into an amorphous polyamide (PA) precondensate with an average molar mass of 1,000 g/mol at temperatures between 230 and 280° C. and normal pressure. Before unifying the precondensate with a melt of 1.70 kg PMMA diol with M n =900 g/mol, 0.35 kg dimeric diol and 24 g of an esterification catalyst, reduce the temperature of the precondensate melt to 230° C. Immediately close the reactor and initiate the polymer building by reducing the pressure. Upon achieving a torque of 25 Nm after approx. 2 h at a pressure of 5-10 mbar, stop the esterification by breaking the vacuum. Discharge and granulate the block polymer.
EXAMPLE 15
Produce an amorphous polyamide oligomer by converting 3.05 kg 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane and 3.67 kg dodecanoic diacid at temperatures of 230-270° C. under normal pressure. After cooling the precondensate melt to 230° C., add in a mixture, which has been tempered to 230° C., consisting of 2.06 kg PMMA diol with M n =900 g/mol, 0.43 kg dimeric diol and 20 g tetra-n-butylzirconate dissolved in n-butanol. Immediately seal the reactor and reduce the pressure (<10 mbar). After the desired torque is achieved, stop the esterification by breaking the vacuum, and discharge and granulate the block polymer.
TABLE 1
Composition and Analytical Results of the Polyamide-
Polymethylmethacrylate Copolymers: Examples 1 to 10 and 12 to 15
Modulus
PA Component
HX-D-XH
T E 6
of Elastic-
RF 1
RD 2
Ex
Type
Conc 4
Type
Conc 4
η rel 3)
[° C.]
ity [MPa]
[MPa]
%
1
Mod. PA-
50.2
PPG
8.4
1.70
140
950
22
200
12
diamine 7
2
Mod. PA-
54.9
PTHF
5.8
1.71
150
1220
24
170
12
diamine 8
3
PA-12
50.7
C36-diol
18.6
1.77
130
230
25
150
4
PA-12
57.9
C36-diol
15.9
1.56
140
300
22
120
5
PA-12
67.2
C36-diol
12.4
1.50
150
530
26
210
6
PA-12
46.5
C36-diol
8.5
1.50
130
600
28
160
7
PA-12
46.6
C36-diol
8.5
1.44
130
520
23
220
8
PA-12
43.8
BD1000 9
17.5
1.50
130
520
22
190
9
PA-12
49.2
C36-diol
18.0
1.46
130
240
25
265
10
PA-12
51.8
poly-
10.6
1.53
150
700
24
125
THF 10
12
amorphous
66.9
poly-THF
4.8
1.50
120
1960
49
10
PA
13
amorphous
57.8
C36-diol
15.8
1.56
90
1470
29
7
PA
14
amorphous
70.9
C36-diol
4.9
1.48
120
1890
33
5
PA
15
amorphous
71.4
C36-diol
4.9
1.62
110
1760
48
6
PA
1 RF = tear strength
2 RD = clongation at break
3 η rel = 0.5 m-cresol (DIN 53727)
4 wt.-%
5 wt.-%
6 T E = T m for crystalline PA 12 or T g for amorphous PA
7 PPG diamine = polypropyleneglycoldiamine
8 PTHF diamine = polyoxytetramethylenediamine
9 BD1000 = polybutylmethacrylate diol
10 poly-THF = polytetrahydrofurandiol
EXAMPLE 16
For purposes of testing the adhesiveness of the bond, two-part DIN tensile bars were prepared on an Arburg Allrounder 350-210-750 and subjected to a tensile test.
Inserts were produced from the inventive block polyester amides, onto which the corresponding homopolymers were sprayed. The processing temperatures were selected such that a partial melting of the inserts on the common contact surface was possible. Table 2 summarizes the tear strengths determined in the tensile test according to DIN 53455.
TABLE 2
Adhesiveness between the polyamide polymethylmethacrylate
copolymers and various polymers: Tear strength of the
two-part tensile bars in [MPa]
Grilamid
Grilamid
Riaglas
Grilamid
Grilamid
Grilamid
Grilamid
Ex.
L16
ELY60
Solef
09000ST
L20
TR55
TR70
TR90
3
9
12
7
8
no test
no test
no test
no test
4
15
11
10
6
no test
no test
no test
no test
5
13
9
7
7
no test
no test
no test
no test
6
19
12
9
8
no test
no test
no test
no test
8
9
8
6
8
no test
no test
no test
no test
9
16
14
11
14
no test
no test
no test
no test
13
12
10
7
10
9
14
7
no test
14
8
6
8
12
5
16
9
no test
15
10
8
10
15
7
30
22
32
Grilamid L16 is a low-viscosity polyamide 12, and Grilamid L20 is a mid-viscosity polyamide 12 manufactured by EMS Chemie. Grilamid L16 LM is a special PA 12 type for cable wrapping.
Grilamid ELY 60 is a copolyamide manufactured by EMS Chemie based on lactam 12, polyetherdiamine and dimerized fatty acid with a melting point of approx. 160° C.
Solef 1008 is a polyvinylidenefluoride made by Solvay with an MVI of 8 g/10 min measured at 230° C. and a load of 5 kg.
Riaglas 09000ST is a PMMA injection molding type with an MVR of 2.3 measured at 230° C. and 3.80 kg bearing mass
Grilamid TR55 and Grilamid TR70 are amorphous copolyamides based on lactam 12, isophthalic acid and 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane with a glass transition temperature of approx. 160° C. or 190° C.
Grilamid TR90 is an amorphous polyamide based on dodecanoic diacid and 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane with a glass transition temperature of 155° C.
EXAMPLE 17
For purposes of testing the bond adhesion, two-part DIN tensile bars were produced on an Arburg Allround 350-210-750 and subjected to a tensile test.
First, inserts were produced from the inventive block polyesteramides, on which Lexan 101, a polycarbonate made by GE Plastics Europe with an MVI of 6 (measured at 300° C. and 1.20 kg bearing mass) was sprayed on. The processing temperatures were selected such that a partial melting of the inserts on the common contact surface was possible.
The tear strength determined in the tensile test according to DIN 53455 equals 18 Mpa.
Surprisingly, a very good adhesion of the block polymers to polycarbonate could be achieved according to the invention.
EXAMPLE 18
On a ZSK-25, given a mass temperature between 200 and 240° C. and a rate of rotation in the range between 150 and 300 UPM and a throughput of 5-10 kg/h
a) Grilamid L16 A (amine-terminated, low-viscosity PA-12) and Plexiglas 6N (PMMA by Röhm) without other additives in a ratio of 1:2, and
b) 1 part Grilamid L16 A and 2 parts Plexiglas 6N are extruded, while adding 10% of a block polyester amide from the examples 6-9.
While in a) a non-granulatable, sharply pulsing strand resulted, or the compound even dripped from the discharge nozzle in the shape of elongated drops and thus could not be extracted, in extrusion b) a homogenous, non-pulsing strand with a smooth surface was formed, which could be granulated without a problem. Examination of the phase distribution via REM reveals that the dispersed polyamide phase in case a) is distributed as spheres or deformed cylinders with a diameter between 2 and 10 μm, while in case b) it is distributed substantially more homogenously, with domain sizes appreciably smaller 0.5 μm. [sic] This result clearly demonstrates the compatibility promoting effect of the inventive block copolymers in polyamide-PMMA blends.
EXAMPLE 19
On an apparatus for cable wrapping, a plastic optical fiber waveguide based on PMMA (Toray PFU FB 1000 L) was coated with the following structure:
inner layer: adhesion promoter from Example 6
outer layer: Grilamid L16 LM
The stripping force for a semi-insulated fiber was measured in a tension-expansion experiment. On average, a force of 50-60 N had to be applied in order to strip the fiber from the cladding. Thus, a very good bond exists between the fiber and the cladding.
EXAMPLE 1 FOR COMPARISON
By coextrusion, a plastic optical fiber waveguide (Toray PFU FB 1000 L) was coated with the following structure:
inner layer: Grilamid L16 A as adhesion promoter outer layer: Grilamid L16 LM
The stripping force on the semi-insulated fiber was measured in a tension-expansion experiment. A force of 10 N had to be applied in order to strip the fiber from the cladding. The bond between the fiber and cladding is insufficient.
EXAMPLE 2 FOR COMPARISON
By coextrusion, a plastic optical fiber waveguide (Toray PFU FB 1000 L) was coated with the following structure:
inner layer: Lotader AX 8900 (Atofina, copolymer from ethylene, methylacrylate and glycidyl acrylate) as adhesion promoter outer layer: Grilamid L16 LM
The stripping force on the semi-insulated fiber was measured in a tension-expansion experiment. A force of 25 N had to be applied in order to strip the fiber from the cladding. The bond between the fiber and cladding is significantly weaker than in Example 18 and fails to satisfy the requirements of a tight fit greater than or equal to 50 N.
It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims. | Polyamide polyalkyl(meth)acrylate block copolymers which are built from polyamide generating monomers in addition to 15-70 weight percent polyalkyl(meth)acrylates as well as products produced from same. The block copolymers are produced by producing polyamide or copolyamide blocks with an average molar mass in the range between 500 and 5,000 g/Mol with an amino end group in a first polymerization or polycondensation step and degassing in order to reduce the water content; adding, in a second step, α,ω-functionalized polyalkyl(meth)acrylate diols; and fully condensing the reaction mixture into high-molecular block copolymer (A) at a reduce pressure in a further polycondensation step; discharging it, or further processing it into molding bodies. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to electronic messages. More specifically, a method and a system for avoiding spam messages are disclosed.
BACKGROUND OF THE INVENTION
[0002] Electronic messages have become an indispensable part of modern communication. Electronic messages such as email or instant messages are popular because they are fast, easy, and have essentially no incremental cost. Unfortunately, these advantages of electronic messages are also exploited by marketers who regularly send out unsolicited junk messages (also referred to as “spam”). Spam messages are a nuisance for users. They clog people's email box, waste system resources, often promote distasteful subjects, and sometimes sponsor outright scams.
[0003] There are many existing spam blocking systems that employ various techniques for identifying and filtering spam. For example, some systems generate a thumbprint (also referred to as signature) for each incoming message, and looks up the thumbprint in a database of thumbprints for known spam messages. If the thumbprint of the incoming message is found in the spam database, then the message is determined to be spam and is discarded.
[0004] Other techniques commonly used include whitelist, blacklist, statistical classifiers, rules, address verification, and challenge-response. The whitelist technique maintains a list of allowable sender addresses. The sender address of an incoming message is looked up in the whitelist; if a match is found, the message is automatically determined to be a legitimate non-spam message. The blacklist technique maintains a list of sender addresses that are not allowed and uses those addresses for blocking spam messages. The statistical classifier technique is capable of learning classification methods and parameters based on existing data. The rules technique performs a predefined set of rules on an incoming message, and determines whether the message is spam based on the outcome of the rules. The address verification technique determines whether the sender address is valid by sending an automatic reply to an incoming message and monitoring whether the reply bounces. A bounced reply indicates that the incoming message has an invalid sender address and is likely to be spam. The challenge-response technique sends a challenge message to an incoming message, and the message is delivered only if the sender sends a valid response to the challenge message.
[0005] Some of the existing systems apply multiple techniques sequentially to the same message in order to maximize the probability of finding spam. However, many of these techniques have significant overhead and can adversely affect system performance when applied indiscriminately. A technique may require a certain amount of system resources, for example, it may generate network traffic or require database connections. If such a technique were applied to all incoming messages, the demand on the network or database resources would be large and could slow down the overall system.
[0006] Also, indiscriminate application of these techniques may result in lower accuracy. For example, if a legitimate email message includes certain key spam words in its subject, the may be classified as spam if certain rules are applied. However, a more intelligent spam detection system would discover that the message is from a valid address using the address verification technique, thus allowing the message to be properly delivered. It would be useful to have a spam detection system that uses different spam blocking techniques more intelligently. It would be desirable for the system to utilize resources more efficiently and classify messages more accurately.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which:
[0008] FIGS. 1A-1E are block diagrams illustrating the application of test methods to incoming messages.
[0009] FIG. 2 is a system diagram illustrating the operations of a system embodiment.
[0010] FIG. 3 is a diagram illustrating how a message state data structure is used in an embodiment.
[0011] FIG. 4 is a flowchart illustrating the processing of a message according to one embodiment.
[0012] FIG. 5 is a flowchart illustrating a test selection process according to one embodiment.
[0013] FIGS. 6A-6B illustrate a test selection process based on test results, according to one embodiment.
DETAILED DESCRIPTION
[0014] It should be appreciated that the present invention can be implemented in numerous ways, including as a process, an apparatus, a system, or a computer readable medium such as a computer readable storage medium or a computer network wherein program instructions are sent over optical or electronic communication links. It should be noted that the order of the steps of disclosed processes may be altered within the scope of the invention.
[0015] A detailed description of one or more preferred embodiments of the invention is provided below along with accompanying figures that illustrate by way of example the principles of the invention. While the invention is described in connection with such embodiments, it should be understood that the invention is not limited to any embodiment. On the contrary, the scope of the invention is limited only by the appended claims and the invention encompasses numerous alternatives, modifications and equivalents. For the purpose of example, numerous specific details are set forth in the following description in order to provide a thorough understanding of the present invention. The present invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the present invention is not unnecessarily obscured.
[0016] An improved technique for testing email messages is disclosed. A multipronged approach is adopted wherein test methods are applied to incoming messages to classify the messages as spam, not spam, or some other appropriate categories. In this specification, the test methods are processes or techniques that generate information useful for determining whether a message is spam. The test methods attempt to classify the message. The state of the message is updated after each test method is applied.
[0017] The classification of the message may be determinate, meaning that the message has reached a state where it will not be further tested, or indeterminate, meaning that the message will be tested further. In some embodiments, a determinate classification is made when a message is classified with reasonable accuracy as either spam or non-spam, and an indeterminate classification is made when a message cannot be accurately classified as spam or non-spam. In some embodiments, a determinate classification is also made when further information and/or resources are needed to classify the message. The measurement of whether the classification is determinant may be a probability value, a confidence level, a score, or any other appropriate metric. An indeterminate classification indicates that the message cannot be classified as either spam or non-spam, although it may still fit under other categories defined by the test method.
[0018] If the classification of the message is indeterminate, the message router then chooses an appropriate test method to be applied to the message next, and routes the message to the chosen test method. In some embodiments, to choose the next appropriate test method, the message router analyzes the state and selects the next test method based on the analysis. The testing and routing process may be repeated until the classification of the message is determinate, or until all appropriate test methods have been applied.
[0019] FIGS. 1A-1E are block diagrams illustrating the application of test methods to incoming messages. In the embodiment shown in FIG. 1A , the test methods are applied to the incoming messages. The results of the test methods have three message categories: “non-spam,” “spam” and “possibly spam.” Both “non-spam” and “spam” lead to a determinate classification for the message. “Possibly spam” indicate that the classification is indeterminate and that further testing is necessary.
[0020] The embodiment shown in FIG. 1B employs many different test methods, including rules, thumbprints, whitelist, address verification, and challenges. The results of the test methods include five message categories: “non-spam” and “spam” that indicate determinate classification, plus “probably spam”, “probably not spam” and “no judgement” that indicate indeterminate classification.
[0021] The test methods, the results of the test methods, the number of test methods and the number of results may vary for different embodiments. A variety of test methods may be used. In some embodiments, the test methods includes using distinguishing properties as disclosed in U.S. patent application Ser. No. 10/371,987 (Attorney Docket No. MAILP001) by Wilson, et al filed Feb. 20, 2003 entitled: “USING DISTINGUISHING PROPERTIES TO CLASSIFY MESSAGES” which is incorporated by reference for all purposes; and using summary information as disclosed in U.S. patent application Ser. No. 10/371,977 (Attorney Docket No. MAILP002) by Oliver, et al (filed Feb. 20, 2003) entitled: “MESSAGE CLASSIFICATION USING A SUMMARY” which is incorporated by reference for all purposes.
[0022] In some embodiments, different test methods may have different results. FIG. 1C illustrates an embodiment in which three test methods, whitelist, rules, and challenge are used in testing. The test methods produce different results. The whitelist test method divides the incoming messages into two different categories: “non-spam” for messages that come from allowable senders, and “address questionable” for messages whose sender addresses are not included in the allowable whitelist of senders.
[0023] The rules test method classifies the incoming messages into five different categories: “non-spam” and “spam” for messages that can be accurately classified according to the rules; “probably spam” for messages that are likely to be spam according to the rules but cannot be accurately classified; “probably not spam” for messages that are likely to be non-spam; and “no judgement” for messages that are equally likely to be spam or non-spam.
[0024] A test method may have different test results in different embodiments. In FIG. 1D , a message is processed by a challenge test. Once a challenge is issued, the message is held by the message router and is not further processed until a response is received. Upon receiving the response, the test method examines the response, and determines whether the message is spam or non-spam accordingly.
[0025] In FIG. 1E , the results of the challenge test have three categories that are all determinate: “spam”, “non-spam”, and “challenged”. Once a challenge is issued by the test, the original message is not further tested and thus the result is “challenged”. In some embodiments, the original message is deleted from the router. The test requires more information and/or resource to answer the challenge. In some embodiments, some information pertaining to the challenge is sent back in the response, and in some embodiments, some resources are required by the challenge. Details of the challenge technique are described in U.S. patent application Ser. No. 10/387,352 (Attorney Docket No. MAILP003), by Oliver, et al (filed Mar. 11, 2003) entitled: “MESSAGE CHALLENGE RESPONSE”, which is herein incorporated by reference for all purposes. When a response arrives, the test examines the response, determines whether the original message is spam or not. In some embodiments, the original message is forwarded on to the intended recipient of the message. In embodiments where the original message is deleted, the response message usually includes the original message text, and is usually processed and forwarded.
[0026] In some embodiments, each message has a state associated with it. The state is stored in a state data structure, implemented in either software or hardware, used to track state information pertaining to the message and the test methods, including test results, test sequence, probability of the message being spam, etc. After a test method is applied to the message, the state is updated accordingly. In some embodiments, a message router uses the state to determine which test method should be applied to the message next.
[0027] FIG. 2 is a system diagram illustrating the operations of a system embodiment. Interface 201 receives the message and forwards it to message router 200 to be routed to various testing modules as appropriate. The interface may be implemented in software, hardware, or a combination. Various test method modules, including rules module 202 , challenges module 204 , thumbprints module 206 , whitelist module 208 , and address verification module 210 , are used in testing. Message router 200 communicates with the test method modules, evaluates the current state of the message, which comprises its test results up to a given point in time, and determines an appropriate classification and further tests to be run, if appropriate.
[0028] After a message is tested by a module, its state is updated based on the test results. If the test results indicate a determinate classification, the message is delivered if it is non-spam, discarded or stored in a special junk folder if it is spam. If the test indicates an indeterminate classification, the message is passed to the message router, which analyzes the state and selects the next test method based on the analysis. In some embodiments, the message router chooses the most distinguishing test method that will most likely result in a determinate classification. In some embodiments, the message router chooses a cheapest test method that consumes the least amount of resources.
[0029] FIG. 3 is a diagram illustrating how a message state data structure is used in an embodiment. This message state data structure keeps track of the tests that have been run, the test results of each test method, and an overall score after each test on a scale of 1-10 for scoring how likely the message is spam. It should be noted that in some embodiments, the current overall score is kept and the history overall scores is not tracked. The higher the score, the more likely the message is spam. The parameters in the data structure and their organization are implementation dependent and may vary in other embodiments.
[0030] The state is available to both the test methods and the message router. After each test, if no determinate classification is made, the state is analyzed and the most distinguishing test method is chosen as the subsequent test method. The most distinguishing test method is a test method that will most likely produce a determinate classification, based on the current state of the message.
[0031] In the embodiment shown, a whitelist test is initially applied to the message. The results indicate that no determinate classification can be made, and thus a rules test is chosen next. The process is repeated until the challenge test is able to reach a determinate classification and classify the message as spam or not spam. After each test, the overall score is adjusted to incorporate the new test results and the state is updated. It should be noted that the state information is cumulative; in other words, the previous state affects the choice of the subsequent test, and thus also influences the next state. In some embodiments, some of the parameters in the current state are summations of previous states; in some embodiments, the parameters in previous states are weighed to calculate the parameters in the current state.
[0032] Different messages are likely to produce different test results and different states, thus, the message router may choose different test sequences for different messages. While the test sequence shown in FIG. 3 is whitelist-rules-thumbprints address verification-challenge, another message may have a different test sequence. For example, after whitelist and rules test, the state of the other message may indicate that a challenge test is the most distinguishing test that will most likely determine whether the message is spam. Thus, the other message has a test sequence of whitelist-rules-challenge. A determinate classification can be reached without having to apply all the tests to the message, therefore increasing the efficiency and accuracy of the system.
[0033] FIG. 4 is a flowchart illustrating the processing of a message. Once a message is received ( 400 ), the processing enters an initial state ( 402 ). A test is then performed on the message ( 404 ), and the message is classified based on the test results ( 406 ). It is then decided whether the test results indicate a determinate classification ( 408 ). If a determinate classification is reached, the message is determinatively classified as either spam or non-spam to be processed accordingly ( 414 ). If, however, the classification is indeterminate, then the state is updated ( 410 ). It is then determined whether there are available tests that have not been used ( 411 ). If all the tests have been performed and there are no more tests available, then the message is processed based on test results obtained so far ( 414 ). Generally, the message is treated as non-spam and delivered to the intended recipient. If there are more tests available, the next test is chosen ( 412 ). The message is then routed to the next test ( 416 ), and control is transferred to the performing test step ( 404 ) and the process repeats.
[0034] The criteria for choosing the subsequent test are implementation dependent. In some embodiments, the message router chooses the most distinguishing test to maximize its chance of reaching a determinate classification; in some embodiments, the message router chooses the cheapest test to minimize resource consumption. Both the cost of each available test and the likelihood of the test discriminating between spam and nonspam may be considered to select the most efficient test. In some embodiments, the next test is selected based on a lookup table that returns the next test based on the tests already taken and the overall score achieved so far. A more complex lookup table may also be used that selects the next test based on the results of specific tests. The decision may also be made adaptively, based on tests that have been determinative in the past for the user. In some embodiments, the results of the tests are input into a statistical classifier, such as a neural network, that is trained based on past data to learn the optimal test selections. User preferences may also be used to select a test that is particularly effective for detecting certain types of spam that are particularly undesirable for the user, or the user may select preferred tests.
[0035] FIG. 5 is a flowchart illustrating a test selection process according to one embodiment. It shows details of step 412 in FIG. 4 . Once it is decided that more tests are available ( 411 ), it is determined whether the state indicates a most distinguishing test among the remaining tests ( 500 ). If a most distinguishing test exists, then the test is selected ( 502 ) and the message is sent to the selected test by the router ( 506 ). If, however, a most distinguishing test does not exist, then the subsequent test is selected based on resource cost ( 504 ). Generally, the cheapest test that incurs the least amount of resource cost is selected.
[0036] FIGS. 6A-6B illustrate a test selection process based on test results, according to one embodiment. FIG. 6A is a table showing a plurality of test methods and their associated parameters. The test methods are sorted according to their resource consumption, where 1 indicates the least amount of resource consumed and 4 indicates the most. The possible results for the test methods are also shown, and are enumerated as the follows: no judgement=1; probably spam=2; probably not spam=3; spam=4; non-spam=5. The maximum result available to each of the test methods is also shown. It should be noted that the values in the table may be different for other embodiments.
[0037] FIG. 6B is a flowchart illustrating a test selection process that utilizes the table shown in FIG. 6A . Once it is decided that more tests are available ( 411 ), a candidate test method that consumes the least amount of resource is located according to the table ( 600 ). The current result stored in the state of the message is compared with the maximum result of the candidate test method. It is determined whether the current result is less than the maximum result of the candidate test method. In some embodiments, the current result is the result obtained from a previous test. If the current result is less than the maximum result of the candidate test method, the candidate test method is selected ( 604 ) and applied to the message ( 416 ). If, however, the current result is not less than the maximum result of the candidate test method, the candidate test method is not selected and control is returned to step 411 to repeat the process.
[0038] An improved technique for testing email messages has been disclosed. A multipronged approach is adopted wherein a plurality of test methods are made available to help classify a message as spam or not spam. The system keeps track of a state associated with a message and its test results from various test methods. A message router uses the state to route the message among the test methods, until a determinate classification is reached. Since the test sequence is selected intelligently, it is more efficient, more accurate, and consumes fewer resources.
[0039] Although the foregoing invention has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. It should be noted that there are many alternative ways of implementing both the process and apparatus of the present invention. Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims. | A system and method are disclosed for routing a message through a plurality of test methods. The method includes: receiving a message; applying a first test method to the message; updating a state of the message based on the first test method; and determining a second test method to be applied to the message based on the state. | 6 |
The Government has rights in this invention pursuant to contract Number NA86AA-D-SG089 (RB/30) awarded by the Department of Commerce.
BACKGROUND OF THE INVENTION
This is generally in the area of drug delivery of compounds to aquatic animals, and in particular uses ultrasound to effect or enhance uptake of compounds by aquatic animals.
Fish farming has become one of the most rapidly growing agricultural industries in recent years. One of the major problems in commercial fish farming is the administration of drugs, peptides, proteins, vaccines and other chemical compounds to the fish. Currently, approaches for the administration of these compounds to fish is by injection, use of implants, incorporation into food, or, for a limited number of agents, via diffusion from the water (with or without a short osmotic shock). In general, all of these methods are labor intensive, often inefficient and sometimes not successful. In many cases it is impractical on a commercial scale to inject each fish or crustacean with drug. The uptake of these compounds coadministered with food or placed directly in the water is inefficient and unpredicatable, often requiring high levels of drug.
Ultrasound has been suggested as a means of administering drugs through the skin. The drug is administered topically to the skin, a coupling gel applied, and ultrasound applied to the drug via a probe placed in contact with the gel. The ultrasound enhances permeation of the drugs through the skin at a controlled rate. The advantages of this technique is that the ultrasound forces some drugs through the skin that could not otherwise be delivered transdermally and the transfer occurs at a controlled rate. Such a method is described in U.S. Pat. No. 4,767,402 to Kost, et al. Applying the ultrasound method for transdermal drug delivery to aquatic animals would be impractical, extremely labor intensive, and the results not predictable, particularly in the case of fish since the skin of a mammal and the scaled skin of a fish are so different. Ultrasound has also been used to force DNA into mammalian embryos under highly controlled laboratory conditions.
It is therefore an object of the present invention to provide a method for effecting or enhancing administration of compounds to a variety of aquatic animals.
It is a further object of the present invention to provide a method for administration of compounds on a large, commercially useful scale.
SUMMARY OF THE INVENTION
A method for administering compounds, including proteins (as used herein, protein includes peptides, polypeptide and protein macromolecules), non-protein drugs, and nucleic acids, to aquatic animals, especially fish, in an aquatic medium by applying ultrasound to the aquatic medium containing the compound to be administered to enhance or effect the uptake of the compound by the animal from the water.
In one example, gonadotropin-releasing hormone analogue (GnRHa) was administered to fish via water to which ultrasound was applied for ten to fifteen minutes at an intensity of 1.7 W/cm 2 . Fish exposed to ultrasound had blood levels of 3.29±1.0 ng/ml of GnRHa as compared to levels of 0.50±0.23 ng/ml for fish exposed to GnRHa in the absence of ultrasound.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph of the levels of GnRHa (ng/ml) in the plasma of the fish over time (minutes), comparing fish exposed to GnRHa in the absence of ultrasound ([dark]) and in the presence of ultrasound ([///]).
DETAILED DESCRIPTION OF THE INVENTION
The efficient administration of compounds into aquatic animals in an aqueous medium is effected, or enhanced, by exposing the aquatic medium containing the compound to be administered to short-term, generally less than one hour, low intensity, generally less than 3 W/cm 2 at the surface of the aquatic animal, ultrasound. Using this approach, a highly significant uptake (P<0.001) of a gonadotropin-releasing hormone analogue (GnRHa) from the water into the blood system of fish was achieved. This method is expected to have tremendous benefits in commercial aquaculture as a simple and highly efficient method for the administration of chemical agents into aquatic animals.
Examples of animals that can be treated using this method include fish, crustaceans (such as shrimp and lobsters), and molluscs. Embryos, hatchlings, and adult aquatic animals can all be treated with this method, although the optimum conditions will vary according to the type, age and condition of the animal. For embryos, conditions will also vary depending on the type of egg. Fish eggs have quite different properties than mammalian or avian eggs since they are usually fertilized externally.
Compounds which can be delivered into aquatic animals using ultrasound include proteins (peptides, polypeptides and protein macromolecules), nucleic acid sequences encoding proteins, non-protein chemical compounds, such as most antibiotics, antifungals, steroids, vitamins, and nutrients, and minerals. Specific examples are hormones (such as gonadotropins, gonadotropin-releasing hormones, growth hormones, and thyroid hormones) and vaccines. These compounds can be used to improve reproduction, growth rates, disease resistance and general performance. The mechanism can also be used to administer small microencapsulated implants or even to "seed" molluscs, for the production of pearls.
The ultrasound is generally applied to the aquatic medium surrounding the animal or its eggs. The compound may be absorbed into the tissues, blood, or, in the case of eggs, into the cytoplasm or nucleus. Ultrasound can travel undiminished for long distances in water, losing only 50% of the energy at a water depth of about 11.5 meters, for ultrasound at 1 MHz, assuming no other medium is present. The distance over which the ultrasound can travel is dependent on the frequency of the ultrasound. At a distance of approximately 38 meters, only about 90% of the intensity of ultrasound at 1 MHz is present.
Ultrasound is defined as sound having a frequency greater than 20 kHz. Ultrasound used for medical diagnostic purposes usually employs frequencies ranging from 0.75 to about 10 MHz. As used herein, frequencies of between 20 kHz and 10 MHz with intensities between 0 and 3 W/cm 2 are generally used to enhance transfer of molecules. Exposures of only a few minutes are usually sufficient since the response time to the ultrasound is very rapid. Care must be taken to avoid excessive exposure, usually in excess of one hour.
Devices are available which emit both pulsed and continuous ultrasound. The specific embodiment of the ultrasound device is not important. Probes, baths, and boxes are all useful depending on where and how the ultrasound is to be applied. Ultrasound devices are manufactured by Sonics and Materials, Inc., Danbury, CT, and Enraf Nonius, Al-Delft, The Netherlands.
Because ultrasound does not transmit well in air, as well as because aquatic animals do better in water, the ultrasound is preferably applied to the water in which the animal is located. In addition, or alternatively, although not preferred, the ultrasound can be applied to the animal or the eggs directly, taking care to avoid overexposure.
The present invention is further demonstrated by reference to the following non-limiting example.
EXAMPLE 1
Administration of Gonadotropin-Releasing Hormone analogue to Goldfish.
Methods
Goldfish (Carassius auratus) 12 to 15 cm long, weighing 23.0±2.9 g were purchased from Ozark Fisheries, Inc., Stoutland, Missouri. The fish were individually marked with tags and stocked in a 180 liter aquarium. The water temperature was maintained at 20° C.
Fish were divided into 2 experimental groups, each consisting of 10 fish. Fish from the first group (control) were immersed in a solution of a nanopeptide analog of the Gonadotropin Releasing Hormone- [D-Ala 6 ,Pro 9 -NET]-LHRH (GnRHa, Bachem, Bubendorf M.W. 1167) and were not exposed to ultrasound. Fish from the second group (ultrasound exposed) were immersed in a solution of similar concentration and exposed to ultrasound. Each fish was introduced into separate 2000 ml glass beakers containing 1200 ml of the GnRHa solution at a concentration of 500 ng/ml. The diameter of the beakers was 13 cm and the depth of water approximately 10 cm. The fish were kept in the beakers for 1 hour. Fish from the ultrasound group were exposed to ultrasound for the first 10 to 15 minutes. The ultrasound was administered using a therapeutic ultrasound generator (Sonopuls 434, Enraf Nonius, Al-Delft, The Netherlands). A 1 MHz probe with an effective radiating area of 5 cm 2 was used, the surface of which was maintained just below the surface of the solution in the beakers. The probe was slowly moved over the beaker surface area during application of ultrasound. The intensity of ultrasound applied was 1.7 W/cm 2 . After 1 hour in the hormonal solution, all the fish were returned to the 180 liter aquarium which contained water without hormone.
Five fish from each group were bled before their introduction into the hormone solution and at 30 and 120 minutes. The five remaining fish in each group were bled at 15, 60 and 180 minutes following their introduction into the hormone solution. For the sampling of blood, the fish were anesthetized in a 300 ppm solution of 2 phenoxy ethanol (Merck). 200-250 μl of blood was removed from the caudal vessels using 1 ml syringes and 23 g needles. The fish recovered from anesthesia rapidly (within 2 to 3 minutes) when replaced into water. Blood samples were placed on ice for 2 to 3 hours and then centrifuged for 10 min at 15,000 rpm. Serum was removed and stored at -30° centigrade for radioimmunoassay (RIA) of the GnRHa.
Radioimmunoassay for [D-Ala 6 ,Pro 9 -NET]-LHRH
A specific, homologous RIA for [D-Ala 6 , Pro 9 -NET]-LHRH was used for the determination of its levels in the serum. 50 μl of a diluted serum sample or a standard were incubated with 50 μl of rabbit antiserum against [D-Ala 6 , Pro 9 -NET]-LHRH in a final volume of 500 μl for 24 h at 4° C. Incubation was performed in 0.01 M phosphate saline buffer pH 7.6 containing 0.2% of BSA. After 24 h, 50 μl of radiolabelled I 125 -[D-Ala 6 , Pro 9 -NET]-LHRH was added to all tubes and the incubation was continued under the same conditions for another 24 h. At the end of this incubation the bound fraction of the [D-Ala 6 , Pro 9 -NET]-LHRH was precipitated using a second antibody, raised against rabbit gamma globulins. The precipitate was counted in a gamma radioactivity counter. The serum levels of the GnRHa were calculated after a log-logit linearization of the standard curve. The sensitivity of the RIA was 0.02 ng/ml and its precision (intra-assay variability) was 3.2%.
Results
The levels of the GnRHa in the plasma of the fish before and during the course of the study are shown in FIG. 1. As expected, no GnRHa was measured in the blood of the fish before their exposure to the hormone solution. There was some uptake of GnRHa from the water by the control fish, with a maximum measured level of GnRHa in the plasma of the control fish being 0.50±0.23 ng/ml after 1 hour of immersion in the hormone solution. The exposure of the fish to 10 to 15 min of ultrasound dramatically enhanced the uptake of the GnRHa from the water into the fish. Plasma GnRHa levels increased to 3.29±1.00 ng/ml after 15 minutes ultrasound exposure and were still elevated 45 minutes later (2.83±0.49 ng/ml). Thirty minutes after fish were exposed to 10 minutes of ultrasound, blood GnRHa levels were 1.36±0.27 ng/ml. During the entire period of immersion in the GnRHa solution (60 minutes), GnRHa levels measured in the plasma of the fish exposed to ultrasound were significantly higher (P<0.001) than the GnRHa levels measured in the plasma of the control fish (FIG. 1).
Upon removal of the fish from the beakers containing the hormone, the GnRHa was cleared from the circulation, and by 180 minutes (2 hours after the transfer to clean water), plasma GnRHa levels in the ultrasound treated fish were not different from those observed in the control fish (FIG. 1).
The data thus clearly demonstrates that a short-term exposure of goldfish to therapeutic levels of ultrasound dramatically enhances the uptake of a nanopeptide from the water into the fish blood.
Modifications and variations of the method for effecting or enhancing uptake of compounds by aquatic animals using ultrasound will be obvious to those skilled in the art from the foregoing detailed description of the invention. Such modifications and variations are intended to come within the scope of the appended claims. | A method for administering compounds, including proteins, non-protein drugs, and nucleic acids, to aquatic animals, especially fish, in an aquatic medium wherein the compound is added to the medium and ultrasound is applied to the medium to enhance or effect the uptake of the compound by the animal. In one example, gonadotropin-releasing hormone analogue (GnRHa) was administered to fish via water to which ultrasound was applied for ten to fifteen minutes at an intensity of 1.7 W/cm 2 . Fish treated with ultrasound had blood levels of 3.29±1.0 ng/ml of GnRHa as compared to levels of 0.50±0.23 ng/ml for fish exposed to GnRHa in the absence of ultrasound. | 8 |
FIELD OF THE INVENTION
This invention relates to the field of water leakage detection, and in particular to a method and apparatus for monitoring leakage in pressurized fluid-filled pipes, such as wastewater force mains and pressurized water distribution systems.
BACKGROUND OF THE INVENTION
Wastewater collection systems are a critical part of urban infrastructure. They collect sewage from homes, businesses and industries and convey it to treatment plants before it's safely released back into the environment. These systems are complex networks of gravity sewers, holding tanks, pumping stations and pressurized pipes known as force mains. Gravity sewers are the primary means of collecting wastewater and conveying it to treatment plants. However, where excavation conditions are difficult or in flat areas or when wastewater needs to be conveyed across rivers or lakes, gravity sewers are not practical and wastewater must be pumped through force mains. Typically, in such situations the gravity sewers flow into holding tanks, from where the wastewater is pumped to gravity sewers on the other side of the river. Pumping is periodic, its duration and period depend on the rate of wastewater flow and capacity of holding tanks. Typically, the duration is between 3 to 5 minutes.
Gravity sewers and force mains deteriorate naturally with time and eventually lose their initial wastewater tightness, starting to leak. Deterioration is caused by corrosion, soil movement, poor construction standards, and in the case of force mains by repeated pressurizing and depressurizing. Leakage of wastewater is especially of concern in the case of force mains at river and lake crossings because it may go undetected for long periods of time and can have severe impact on the environment. A number of catastrophic incidents have occurred in Canada and the United States in recent years. This risk needs to be addressed and therefore there is an urgent need for reliable technologies to continuously monitor leakage in these critical pipes.
Technologies that may be applicable include acoustic leak noise correlation, mass balance, pressure analysis, and temperature monitoring using fibre-optic sensors.
Mass balance, pressure analysis, and temperature monitoring using fibre-optic sensors are costly to implement. Also, these technologies have been developed primarily for monitoring leakage in oil and gas pipelines under steady state conditions. They have not been demonstrated or evaluated for monitoring of wastewater force mains, which normally operate under transient conditions.
Acoustic leak noise correlation technology is well established for detecting and pinpointing leaks in water transmission and distribution pipes. However, like other technologies, its application to wastewater force mains had not been demonstrated in the past. It is commonly believed that the application of acoustic correlation to force mains is fraught with difficulties due to high background noise caused by nearby pumping stations, excessive signal attenuation caused by the presence of undissolved gases, and compressible solid matter; variable acoustic propagation velocity; relatively low pipe pressure; and the requirement for large sensor-to-sensor spacing.
Additionally, while leaks in pressurized water distribution systems can generally be detected using acoustic leak noise correlation technology, problems can arise when the leaks are very small since the generated noise level in this case can be very low.
SUMMARY OF THE INVENTION
In accordance with the present invention leakage in a pressurized pipe, such as a wastewater force mains, is monitored using acoustic leak noise correlation but not in the usual way, i.e., not while the pipe is under positive internal pressure. Following pump shutdown, negative internal pressure develops in force mains due to the fact that the wastewater continues to flow along the mains by inertia. It has been found unexpectedly that this negative pressure produces favourable conditions for acoustic correlation, i.e., high-enough acoustic signals created by fluid or air drawn into the pipe through the leak in the absence of high background noise from pumps.
Another application of the invention is for leak testing of newly constructed pipes. These pipes have to pass stringent static pressure tests to find small leaks. Many of the small leaks that cause pipes to fail a pressure test are very hard to locate. Currently, these small leaks cannot be detected using the “traditional method”, i.e., under positive pipe pressure. The only way to currently find them is to excavate large lengths of the pipe, which is very expensive. Drawing air or water into fluid-filled pipes creates much louder noise than that created by drawing fluid out of pipes. This creates more favourable conditions for the correlation method to detect these small leaks (e.g., leak signal levels above the noise floor of sensors). Negative pressure can be induced by isolating a pipe section (e.g., closing end valves) and drawing water or air through a tapped location using a manual or powered pump.
The invention is in many ways counterintuitive. While it would be expected that one would need to pressurize the pipe in order to detect the leaking fluid (clearly fluid does not leak from the pipe when it is under zero pressure), the invention recognizes the fact that if negative pressure conditions are created in the pipe, external fluid will leak into the pipe at the same location, and the noise created by this leaking fluid can be detected and analyzed by cross correlation techniques because it gives a good signal in the absence of extraneous noise caused by pumps. In one embodiment, the invention takes advantage of the fact that negative pressure is naturally created in the pipe in the period following pump shutdown.
Thus, in accordance with a first aspect of the invention there is provided a method of detecting leakage in a pipe for carrying a pressurized fluid, comprising creating conditions of negative pressure in said pipe so that external fluid is drawn into said pipe to generate noise or vibration at a leak location; generating signals corresponding to said noise or vibration from spaced sensors located on said pipe; and analyzing said signals to determine the location of said leak.
In the case of a wastewater force mains, the negative pressure is generated during a period of pump shutdown due to the inertia effect of the water on the downstream side of the pump, which will initially tend to keep flowing after the pump has been shut off. The pump normally includes a check valve to prevent reverse flow and keep the pump primed. The time the negative pressure remains usable depends on the nature of the leak and pipe. The larger the leak the faster negative pressure is dissipated. In pilot tests undertaken to demonstrate this invention, the largest leak induced was a substantial 5 liters per second (fully open 2-inch valve). At this leak flow rate, negative pressure in the pipe held steady at ˜2.5 psi (at leak location) for the whole duration of pump shutdown (5 to 10 minutes). An other parameter that is critical is maximum sensor spacing, which was shown to be at least 300 meters.
In the case of a pipe laid across a river, acoustic noise in the pipe can be monitored continuously and simultaneously at two inland points on the pipe, close to either bank of the river. Either hydrophones or vibration sensors are used to pick up acoustic noise, depending on material type, diameter and length of the pipe section to be monitored.
Hydrophones may be inserted inside pipes at existing or specially created taps. Alternatively, a hydrophone array may be inserted. Alternatively, vibration sensors may be attached to the external surface of pipes.
In the case of a water distribution system, a section of pipe can be isolated, for example, by closing appropriate valves, and negative pressure created by pumping water out of the isolated section. This embodiment provides a way of detecting very small leaks. Typically, before a water distribution system is commissioned, the system is pressurized under static conditions to detect any leaks. Leaks that typically cause pipes to fail static pressure tests are typically very small in size and therefore in most cases cannot be pinpointed using cross-correlation techniques. However, if pipe sections are isolated and a negative pressure created in accordance with the invention, ingressing air or fluid creates a substantial amount of noise which more readily lends itself to acoustic noise cross-correlation techniques.
Acoustic signals may be transmitted over wire or wirelessly in either analogue or digital form to a receiving station. Received acoustic signals are manually or automatically recorded and correlated. This can be performed using a modified version of the LeakfinderRT system, patented by NRC-IRC. The LeakfinderRT system can also be modified to automatically alarm pipeline operators when a leak is detected and provide information about its approximate location according to pre-set thresholds and criteria.
The invention overcomes the problem of high background noise of pumping stations, is capable of detecting both small and large leaks, does not require taking pipes out of service to install instrumentation, and can be easily implemented using a Windows-based software for embedded computers and readily available hardware.
In accordance with a second aspect of the invention there is provided a system for detecting leakage in a pipe carrying pressurized fluid, comprising at least two spaced sensors located on the pipe; means for periodically creating negative pressure in the pipe to draw fluid or air into the pipe at the location of a leak; and a computer programmed to determine the location of the leak by analyzing signals representing noise or vibration occurring at the location of said leak.
The sensors can be located on or inside the pipeat opposite sides of the location of the leak or at opposite ends of the pipe section to be monitored.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a general schematic diagram illustrating the method for locating a leak in a pipe;
FIG. 2 is a schematic diagram of a particular experimental setup for illustrating the present invention;
FIGS. 3 to 33 show test results for the experimental setup shown in FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 a pipe 10 has developed a leak 12 . A pair of hydrants 14 , 16 are arranged at spaced locations. The leak 12 is located at a distance L 1 from hydrant 14 , and distance L 2 from hydrant 16 . The total separation of the hydrants is D.
Hydrophone sensors 18 , 20 are located at respective hydrants 14 , 16 . These are connected to an RF transmitter 22 which communicates with a receiver 24 connected to a computer 26 . The location of the leak can be determined using LeakfinderRT software running on the computer 26 .
LeakfinderRT is a system that was developed by the National Research Council Canada for locating leaks in pressurized fluid-filled pipes, especially municipal water distribution and transmission pipes. In a traditional application, LeakfinderRT utilizes the cross-correlation method to locate the hissing sound created by a pressurized fluid as it leaks out of the pipe. This system is fully realized in software for personal computers (PCs) running under Microsoft Windows. It uses the PC's soundcard and other multimedia components to record and play back acoustic leak signals. It also uses the PC's processor to perform the cross-correlation operation and associated digital signal conditioning operations. Modem PCs incorporate fast processors and high-resolution soundcards and, hence, offer several advantages over existing commercial hardware implementation of the cross-correlation method. Hardware components of the Leakfinder RT system include leak sensors (either vibration sensors or hydrophones), wireless signal transmission system, and a PC. The software can be installed on either a notebook, desktop or embedded PC that has a soundcard with a stereo line-in port and it has a friendly menu-driven interface.
The LeakfinderRT system incorporates an enhanced correlation function. For narrow-band leak noise, this function dramatically improves the definition of correlation peaks. This is important for plastic pipes, multiple-leak situations, and in settings where leak sensors have to be closely spaced. Also, the enhanced correlation function is more effective than the traditional correlation function for small leaks and for situations of high background noise. The enhanced correlation function technique is described in U.S. Pat. No. 6,453,247, the contents of which are herein incorporated by reference.
The cross-correlation function can be directly applied to problems involving the measurement of distance (i.e., ranging problems) or the measurement of velocity—the distance can be determined given the velocity or vice versa. Similarity between sensed leak signals is essential for obtaining an accurate time delay—hence, the assumption of a non-dispersive medium, i.e., one in which the propagation velocity does not vary with frequency. If this is not the case or if the propagating phenomenon is not sufficiently broad-band, the cross-correlation function will not have a distinct peak.
Locating leaks in pressurized fluid-filled pipes is a classical application of the cross-correlation method. Two things make this possible. First, the propagation velocity of leak sounds in pressurized pipes is nearly constant over the dominant frequency range of leak sounds. Second, fluid-filled pipes transmit leak signals for long distances. Therefore, the shape of leak signals does not change significantly as they travel away from the leak, which is a prerequisite for a successful correlation.
Leak noise signals are measured at the two points that bracket the location of a suspected leak. The cross-correlation function of the two leak signals is then calculated to determine the time delay between the two signals. Time delay between the two leak signals is the result of one measurement point being closer to the leak location than the other. If the two measurement points are symmetrically positioned about the leak location, leak signals will arrive simultaneously at the two points and the time delay will be zero. On the other hand, if the leak location is exactly at the position of one of the two measurement points (or, equivalently, it is not between the two points), the time shift will be equal to the distance between the measurements points divided by the propagation velocity of leak noise in the pipe.
The correlation magnitude of two leak noise signals is the summation of their product as a function of time shift. In simple terms, the correlation value at time shift τ is computed by first shifting one of the signals by τ relative to the other signal. Then the two signals are multiplied, point-by-point, and the products are summed. The correlation function will display a peak at the time shift, which corresponds to the actual delay between the two leak noise signals (this is the time at which the two signals overlap).
The time delay τ max corresponding to the peak of the cross-correlation function is determined automatically. In reference to FIG. 1 , the time delay between the two leak noise signals is related to the location of the leak relative to measurement points by
τ max = L 2 - L 1 c ( 1 )
where L 1 and L 2 are the positions of the leak relative to sensors 1 and 2 , respectively, and c is the propagation velocity of the leak sound in the pipe. By substituting L 2 =D−L 1 in the above equation, the position of the leak relative to point 1 is found as
L 1 = D - c · τ max 2 ( 2 )
where D is the distance between the sensors, either measured on site or read off system maps. The propagation velocity can be specified if it was measured onsite or it can be calculated theoretically based on input for pipe material type and diameter.
If there is more than one leak between sensor positions 1 and 2 , the cross-correlation function will have a peak corresponding to each leak. However, if the leaks are closely spaced, the peaks will overlap and distort the corresponding time delay. The peak width depends on the bandwidth of the leak noise; the wider the frequency bandwidth of leak signals, the narrower the cross-correlation peak. The frequency bandwidth of leaks in metal pipes is much wider than that of leaks in plastic ones. For metal pipes, it may be possible to resolve leaks that are 6 m apart; for plastic pipes it may not be possible to resolve accurately leaks that are less than 20 m apart.
Pilot Field Tests
Setup
Field tests were performed at a dry-land site in Winnipeg, Canada. The site has a 450 mm diameter 1800 meters long PVC force main that was installed in 1988 at a depth between 1.5 and 3 meters. Soil type at the site was silty clay.
Acoustic correlation tests were performed on a 300-meter long segment of the pipe (corresponding to the maximum anticipated river crossing length) starting at about 50 m from the pumping station. The location of the test pipe segment close to the pumping station, its PVC material type, large 450 mm diameter and 300-meter length were deliberately selected. These were believed to be representative of the most challenging conditions for acoustic correlation of leak signals in river-crossing force mains.
The experimental layout for the tests is shown in FIG. 2 , and is similar to FIG. 1 . Pumping station 28 has two 8-inch pumps that operate alternately under normal flow conditions and simultaneously under high flows, e.g., during rainstorms. Weather conditions were mostly dry and clear during the tests; it rained heavily for one hour only. Pressure in the force main at approximately 250 meters from the pumping station was about 10 psi when only one pump was on and 15 psi when both pumps kicked in. The pump includes a controller 40 that periodically runs and shuts down the pump, depending on a preset level of wastewater in holding tanks.
Instrumentation and Software
Instrumentation and software used for measuring, recording and analysis of leak signals were proprietary but available commercially. Accelerometers, geophones and hydrophones made by Echologics Engineering Inc. were used to measure leak noise signals. Accelerometers were of the piezoelectric type with internal preamplifiers and had a sensitivity of 1 volt/g (where g is the unit of gravitational acceleration equal to 9.8 m/s 2 ). Geophones were of the rotating coil type with a special active electromagnetic interference shield and had a sensitivity of 1 volt/cm/second. Hydrophones were of the piezoelectric type with externally housed preamplifiers and had a sensitivity of 42 volts/bar (where bar is the unit of atmospheric pressure equal to 14.5 psi).
Accelerometers and geophones were mounted on top of the force main by magnetically attaching them to small steel plates glued to the main's surface. Hydrophones were housed in special adaptors that were fitted into 2-inch taps in the force main. Hydrophone adaptors were equipped with ⅛-inch valves to release entrapped air after attaching them to the main. For some measurements, signals from hydrophones were attenuated by electrically connecting appropriate capacitors across input terminals of its preamplifier, in parallel with the hydrophone transducer.
Leak signals picked up by sensors were fed into two 460 MHz RF wireless transmitters. A corresponding 2-channel receiver at a remote recording station picked up broadcasted signals. Transmitters contain a power supply source for sensor preamplifiers and specially designed automatic gain amplifier for conditioning of signals before broadcasting. The wireless transmission system operated in a licensed UHF frequency band and was made by Echologics Engineering Inc. Its line-of-sight range extends up to 3 km. Wireless transmitters were colour coded Blue and White and are referred to in this report as “Blue station” and “White station”. The Blue station was always connected to the sensor closest to the pumping station.
Wirelessly received leak noise signals were then fed into the stereo audio line-in port of a portable PC for recording and analysis by LeakfinderRT software version 5.49. The portable computer was of the tablet type with a 1 GHz Intel Pentium M processor (Compaq model TC1100).
Test and Analysis Procedures
A simulated leak with adjustable flow rate was created in the selected 300-meter long test pipe section at approximately 250 meters away from the pumping station. The pipe was excavated and then tapped using a saddle tapping clamp with a 2-inch ball valve 30 . A 2-inch magnetic flow meter 32 was attached after the ball valve to measure leak flow rate. A pressure gauge 34 was installed on the upstream side of the flow meter. A 2-inch gate valve was attached after the flow meter to adjust leak flow rate. Wastewater from the simulated leak was disposed through a rubber hose that ran from the outlet of the gate valve to a nearby combined sewer manhole.
The pipe was also excavated at six other locations at about 50-meter intervals from the location of the simulated leak to attach vibration sensors 40 to the pipe's external surface to measure its acceleration or velocity. At the two most extreme excavations, the pipe was tapped using saddle tapping clamps with 2-inch ball valves to attach hydrophones to measure sound waves in the wastewater inside the pipe. Pressure sensors 34 , 38 were added to sense the pressure at the location of the hydrophones. Pressure sensor 36 senses pressure at the flow meter 32 .
The gate valve of the simulated leak was initially left open continuously regardless of whether the pipe was pressurized or not but later check valves were connected. Sensors were attached to the pipe at two selected locations bracketing the simulated leak. Simultaneous recording of leak signals picked up by the two sensors started once wastewater flowed from the simulated leak. Recording was terminated when leak flow stopped. Leak signals were cross-correlated onsite in real time.
Cross-correlation tests were performed for different combinations of leak flow rate and sensor type and spacing. Leak flow rate was approximately 1, 3 or 5 liters per second achieved by opening the leak's 2-inch gate valve 2, 5.5 and 11 turns (valve was fully open at 11 turns). A leak flow rate smaller than ˜1 liters per second could not be achieved, as the opening of the gate valve would quickly get blocked with dirt. A flow rate of 5 liters per second was the maximum achievable rate. Leak signals were picked up by pairs of accelerometers, geophones or hydrophones spaced at 100, 150, 200, 250, or 300 meters.
Results
Regardless of the flow rate of the simulated leak, acoustic signals measured with hydrophones at 0 and 300 m, while pipe pressure was 10 psi (at leak location) had a poor cross-correlation function and subsequently the leak could not be detected. The correlation function did not even have a peak corresponding to the out-of-bracket noise created by the pump(s) at the nearby pumping station. Pump noise picked up by the hydrophone at 0 m was extremely high and was distorted on a high-quality audio headset. It was believed that high output of the 0 m hydrophone transducer was overloading its preamplifier and the automatic gain circuit. In subsequent measurements, leak signals from the transducers of the hydrophones at 0 and 300 m were attenuated by up to 60 and 10 dB, respectively. This eliminated signal distortion but the cross-correlation function remained poor.
Similarly, acoustic leak signals measured with geophone pairs located at 0 and 300 m, 150 and 300 m, and 150 and 250 m also had poor cross-correlation functions and subsequently the simulated leak could not be detected. Leak signals measured using either hydrophones or geophones had low coherence function across the whole frequency range. This indicates that the measured acoustic signal pairs were incoherent, i.e., they were unrelated or not caused by the same source (see FIG. 3 ).
It was initially believed that the poor coherence cross-correlation of measured acoustic leak signals could be attributed to one or more of the following reasons:
Low pressure in the pipe (10 psi) leading to only weak acoustic noise from the leak. Excessive free air in wastewater inside the pipe leading to severe attenuation of the leak noise. Insufficient signal duration to average out interfering noise as the pipe was under pressure for ˜3 minutes only at a time.
However, it was later discovered that the real reason was that the pipe segment between sensor pairs was not fully filled with wastewater at the location of one or both sensors. When pumping stopped, negative pressure developed in the pipe and air was drawn in through the simulated leak. This eventually led to the formation of an air cavity at the top of the pipe along a large pipe section between sensors. This disrupted the propagation of leak signals in the wastewater core and reduced their level below the threshold of sensors. When pumping resumed, it was for no more than 3 minutes and it appears that this was not long enough to refill the pipe section between sensors.
The air cavity was confirmed based on the cross-correlation function of leak signals measured with geophones at 150 and 250 m while pumping was off and air being drawn into the pipe through the leak opening. The cross-correlation function thus obtained had a definite center peak that corresponded to the actual position of the leak (see FIG. 4 ). Cross-correlation function of similar measurements of leak noise signals but with geophones at 250 and 300 m had a clear peak corresponding to out-of-bracket noise from air being drawn in through the leak (see FIG. 5 ). Acoustic velocity based on this peak was very close to the velocity of sound in air (equal to 340 m/s at a temperature of 15° C. sea level). A similar result was obtained based on leak signals measured with accelerometers. These results were taken as an indication that the sound of air being drawn into the pipe through the leak propagated through a continuous air cavity along the pipe between vibration sensors.
Further measurements of leak signals were made while pumping was off and air being drawn into the pipe through the leak (open 2 and 5 turns) but with geophones at 150 and 300 m (e.g., see FIGS. 6 and 7 ). The corresponding cross-correlation function had a very clear peak that led to the exact position of the leak at 45.2 m from the sensor attached to the Blue transmitter located at 150 m, when an acoustic velocity of 340 m/s was used ( FIG. 8 ). This again confirmed that the sound of air being drawn into the pipe through the leak propagated through a continuous air cavity along the pipe between the two geophones. However, cross-correlation functions were poor and the leak could not be detected based on similar measurements with geophone pairs at 0 and 300 m, 50 and 300 m, and 100 and 300 m (see FIG. 9 ). This was taken as an indication that when pumping stopped, sufficient vacuum remained in the pipe to hold back a full wastewater column between the pumping station and a point between the 100 and 150 m excavations.
A 2-inch air intake check valve was subsequently installed in the pipe at the 0 m excavation. The valve remained closed during pumping and promptly opened as negative pressure developed in the pipe when pumping stopped. Measurements of leak signals were then repeated with geophone pairs at 100 and 300 m and at 150 and 300 m while pumping was off and air being drawn into the pipe through both the leak opening and the air intake valve at 0 m (see FIGS. 10 and 11 ). In both cases, cross-correlation functions had a clear peak corresponding to the location of the simulated leak and another peak corresponding to the out-of-bracket noise created by air drawn into the pipe at the intake valve at 0 m.
In view of successfully detecting the simulated leak while pumping was off and the subsequent condition of air being drawn in at the leak and since the focus of these pilot tests was on river-crossing force mains, the design of the simulated leak was then altered as follows. A “T” adaptor was attached to the leak's gate valve and its ends fitted with check-valves acting in opposite directions. The outward opening check-valve was reconnected to the rubber hose that ran to a combined sewer manhole. This valve opened to release wastewater when a pump was on. On the other hand, the inward opening check-valve was connected to a rubber hose that ran to a nearby aboveground water tank replenished by a 2000-gallon water truck. This valve opened allowing water to be drawn into the pipe as negative pressure developed in the pipe when pumping stopped.
Acoustic leak signals were then measured with geophones at 150 and 300 m while water was being drawn into the pipe through the simulated leak due to negative pressure developed in the pipe following pump shutdown. Unfortunately, the cross-correlation function of these leak signals did not display a pronounced peak and hence the leak could not be detected (see FIG. 12 ). Following these measurements, it started to rain heavily for about one hour. During this time and for a short period after, both pumps in the pumping station were on continuously. The gate valve of the simulated leak was turned off to reduce runoff back to the pumping station hoping to hasten the pumps shutdown.
With geophones still at 150 and 300 m, acoustic signals had a cross-correlation function with a pronounced out-of-bracket peak on the side of the pumping station (see FIG. 13 ). This peak was achieved after both pumps were operating continuously at the pump station for almost one hour. Both pumps were on and the valve of the simulated leak was closed during the test. This was the first time that a peak corresponding to noise from the pumping station was detected since the beginning of field tests 4 days earlier. The reason that noise from the pumping station had become detectable was believed to be that as a result of prolonged pumping the pipe had become fully filled with wastewater from the pumping station to at least the 300 m excavation. A continuous wastewater core made it possible for acoustic noise from the pumps to propagate to both sensors through the wastewater core. This was confirmed by the fact that acoustic velocity corresponding to the out-of-bracket peak was very close to the theoretical value of 440 m/s for a water-filled pipe of the same type and diameter. When the gate valve of the simulated leak was then opened 2 and 5.5 turns, while above conditions continued, the cross-correlation function had no peak corresponding to the location of the simulated leak; only a pronounced peak corresponding to the out-of-bracket noise from the pumping station (see FIG. 14 ).
After having the force main operate normally overnight, acoustic signals in the main were measured with geophones at 0 and 300 m while a pump was on and the simulated leak still shut from the previous day. From the outset the resulting cross-correlation function displayed a very pronounced out-of-bracket peak on the side of the pumping station (see FIG. 15 ). The corresponding acoustic velocity was about 465 m/s, which is close to the theoretical value of 440 m/s. This indicated that while the pipe operated normally overnight, it had the time to fill with water to at least the 300 m excavation and remained so afterwards. To maintain this condition, air was not allowed to be drawn into the pipe through the simulated leak in later field tests. There were no distinct peaks in cross-correlation functions from similar subsequent measurements while the pumps were off and the simulated leak still not turned on (see FIG. 16 ).
While geophones were still at 150 and 300 m, leak noise signals were then measured when pumping stopped and while water was being drawn in at the simulated leak (5.5 turns open). The resulting cross-correlation function had a distinct peak that accurately corresponded to the actual location of the simulated leak. However, subsequent repeats of these measurements failed to detect the leak; the reason is believed to be as follows. The more water drawn into the pipe through the leak, the closer the free end of the wastewater column became to the pipe section between leak sensors, before it reached steady position. Since negative pressure is believed to be highest near the free end, it will also increase in the pipe section between sensors (i.e., lead to more negative pressure). Subsequently, more of the air/gases that are dissolved in the wastewater are released as free bubbles that slow down acoustic waves and significantly increase the attenuation of acoustic leak signals making them undetectable. This was confirmed based on measured acoustic velocities that decreased with time as more water was drawn into the pipe. Acoustic velocity decreased from ˜470 m/s before water was drawn in (see FIG. 15 ) to ˜400 m/s a while after water started to be drawn in (see FIGS. 17 and 18 ), then it stabilized at about 425 m/s (see FIGS. 19 and 20 ).
In further measurements of acoustic signals with hydrophones at 0 and 300 m while pumping was on, there were no peaks in cross correlation functions that corresponded to the simulated leak regardless of its size (2, 5.5 and 11 turns open). There was only a distinct out-of-bracket peak on the side of the pumping station (e.g., see FIGS. 21 and 22 ). It made no difference whether the signal from the transducer of the hydrophone near the pumping station was attenuated by 40 dB or not.
Finally, the simulated leak was detected as a distinct peak in the cross-correlation function of acoustic signals measured with hydrophones at 0 and 300 m while pumps were off and water drawn in through the leak by negative pipe pressure (e.g. see FIGS. 23 , 24 , and 25 ). This was achieved for small, medium and large leak openings (gate valve 2, 5.5 and 11 turns open), both soon after the leak was opened and several hours later, i.e., after the pipe had reached a steady hydraulic state. However, as expected, there was a discrepancy in the predicted location of the simulated leak. The predicted location was closer to the Blue wireless station by 5 to 30 m than the actual location.
Discrepancy in predicted leak location is believed to be due to variation of acoustic velocity along the pipe, specifically being higher between the Blue station and leak than between the leak and White station. As noted earlier, negative pressure in the pipe after pumping stops is believed to be highest near the free end of the wastewater core and becomes less severe in the direction of the pumping station. Subsequently, more of the dissolved air/gases are released as free bubbles in the White station to leak section than in the leak to Blue station section. The more bubbles in the wastewater the slower the acoustic velocity.
As more water was drawn into the main through the simulated leak, the free end of the wastewater core became closer to the pipe section between sensors and hence the difference in the negative pressures in the White station to leak and leak to Blue station became greater. Subsequently, predicted location of the simulated leak became progressively closer to the Blue station with time (compare FIG. 23 with FIG. 26 ). In another test, the peak in cross-correlation moved closer to the Blue station as more signals were summed into the average of the Fast Fourier Transform. The most accurate predicted location was obtained when opening the leak after it was shut for a long period (see FIGS. 27 and 28 ), which helped keep the free end of wastewater core further down stream since no negative pressure was relieved at the leak.
The high frequency content of leak signals decreased progressively with time (compare FIGS. 29 and 30 ). The progressive change in the predicted leak location with time was much slower when the leak's gate valve was open only 2 turns than when it's open fully. This is expected since the less water drawn into the pipe, the slower the free end of the wastewater core moves towards the pipe section between acoustic sensors.
An opposite trend was observed for measured acoustic velocity in the pipe based on the out-of-bracket cross-correlation peak corresponding to noise from the pumping station. The velocity progressively increased with time (e.g., compare 31 , 32 and 33 , performed in sequence). In other tests, the measured acoustic velocity became faster as more signals were summed into the average of the Fast Fourier Transform. It was also observed that measured acoustic velocity increased as the flow rate of the simulated leak decreased.
Based on the abovementioned pilot tests on a 450 mm diameter and ˜300 m long PVC pipe section having a simulated leak, it can be correlation of acoustic leak noise signals, while fluid in the pipe is under negative pressure, is viable for continuous monitoring of leakage in river-crossing wastewater force mains. Both small and large simulated leaks were successfully detected although. The simulated leak, regardless of its size, could not be detected in the usual way, i.e., under positive pressure while the pump(s) were on.
Negative internal pressure that develops in force mains following pump shutdown produced favourable conditions for acoustic correlation, i.e., high-enough acoustic signals created by water drawn into the pipe through the leak while background noise was low. Success was achieved using hydrophones ˜300 m apart, a distance deliberately selected as maximum river-crossing pipe length. However, predicted leak location was off by up to 10% of sensors spacing. This was expected due to the variation of acoustic velocity along wastewater pipes.
When implementing acoustic correlation for river-crossing force mains, hydraulic models should first be developed for flows in these mains. The models would be used to verify if necessary conditions are met, namely that the pipe section between intended sensor locations remains fully filled with wastewater and is under negative pressure following pump shutdown. | A method of detecting leakage in a force main involves placing at least two spaced sensors on the force main. Liquid is pumped through the pipe by means of a pump. The pump is shut down for an interval of time, and during the period following pump shutdown while negative pressure is present in the pipe, signals are generated at the sensors due to noise or vibration resulting from fluid being drawn into the pipe. The position of a leak in the pipe is determined by correlating the leak noise signals generated while the pipe is under negative pressure. Alternatively, the invention can be applied to a pressurized pipe, in which case conditions of negative pressure can be deliberatively created for a period to draw in fluid from the outside. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to a processor system methodology. It particularly relates to a method and apparatus for providing an early indication of a processor soft error being propagated through a computing system.
[0003] 2. Background
[0004] Modern semiconductor process technology is creating processors with smaller sizes to reduce hardware space and increase processor efficiency. However, the smaller sizes make the modern processor more susceptible to single event upsets that are transient errors (temporary or soft errors) caused by exposure to cosmic rays and/or alpha particles. Alpha particles, via atmospheric radiation or exposure to trace levels of radioactive materials in packaging, may permeate the computing processor and cause state devices (e.g., flip-flops) to make unplanned transitions from one state to another (e.g., bit value changes from 1 to 0). Also, for computing processors designed with domino logic (a type of circuit design of cascaded logic that are pre-biased), these transient errors may propagate throughout the entire system logic causing further instability and ultimately a hard failure (e.g., device taken out of service).
[0005] Additionally, “silent data corruption” may develop in processor computing systems where errors occur but are not detected by error checking logic. A hypothetical example may be a misplacement of the decimal point when performing accounting operations. Although a definite error has occurred (e.g., $10,000.00 instead of $100.00 payment), the accounting operations continue to completion and the system believes all operations were completed successfully. This type of “silent error” encourages the design of parallel processing to ensure that all computing elements calculate the same result (answer).
[0006] Several methods may be used for error detection/correction where one common method is the use of error detecting bits (e.g., parity bits) to help detect errors when they occur. Using this technique, a bit error may be detected when a parity bit is commonly applied to an 8-bit data field (one of the nine bits is in error). For this simple use of parity bits, the error is ambiguous as all that is known is that there is an error, and there is no information about what kind of error or what recovery mechanism can be implemented. Another technique uses error correcting code (ECC) memory to actually correct errors. This technique uses multiple parity bits, each having a different definition, to help uniquely specify and correct the error. Each parity bit used indicates an error in a subset of the data field which helps narrow down the possibilities of exactly which bit is in error. An additional technique uses parity syndrome bits where the unambiguous errors occurring may be detected and also corrected since this method identifies the bits in error.
[0007] Modern processor systems commonly employ a multiple processor structure where parallel processing is performed using a plurality of processors (usually linked in lockstep) to execute instructions and compute answers simultaneously. These processing systems typically use ECC logic and parity syndrome logic to detect and correct constant errors occurring along critical data paths (paths tied to memory arrays). However, soft (transient) errors may occur along the non-critical data paths (paths along which the instruction steam is processed and executed) within the processor that use random logic.
[0008] For these parallel processing systems that are commonly connected in a functional redundancy check, both processors execute the instruction stream, along these non-critical data paths, on a clock by clock basis and compare the resulting architectural state updates. If the architectural states (computed answers) differ, an ambiguous error has occurred (similar to the simple use of parity bits). There is enough information to determine that there is a problem, but unless there is sufficiently redundant information, logic or software cannot determine which information is the correct one. The appearance of soft errors where only the architectural state is being compared will corrupt the program flow being currently executed. If this is a restartable transaction in a database system, the operating system software may simply restart the program flow. Alternatively, however, if the operating system (OS) is performing critical system table updates, the error may cause an OS panic and system crash. Somewhere between these two extreme responses would be a system application that just suddenly terminates, leaving the system application user in an unknown state and clearly without his work finished. To prevent these undesirable responses from occurring, there is a need to protect the non-critical data paths of the processor system with a mechanism that provides early detection of soft errors within stages of a multiple stage, pipelined processor system before they propagate to ambiguous error detection.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 illustrates a prior art pipeline logic architecture.
[0010] [0010]FIG. 2 illustrates a prior art processor memory architecture.
[0011] [0011]FIG. 3 illustrates a prior art pipeline flush architecture.
[0012] [0012]FIG. 4 illustrates a prior art multiple processor system architecture.
[0013] [0013]FIG. 5 illustrates a pipeline logic architecture for a multiple processor system in accordance with an embodiment of the present invention.
[0014] [0014]FIG. 6 illustrates a pipeline flush architecture for a multiple processor system in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0015] [0015]FIG. 1 illustrates a prior art pipeline logic architecture 100 for a processor system. The logic architecture 100 includes a first pipeline stage 115 , and a succeeding pipeline stage 125 (pipeline stage +1). Both pipeline stages 115 , 125 include a plurality of data input/output devices (e.g, functional units, flip-flops) 110 , 120 for instruction processing (e.g., fetch, decode, etc.) during operation of the processing system. The pipeline stages 115 , 125 are interconnected by logic elements 135 that may perform a variety of logic operations (e.g., OR, AND, etc.) to facilitate operation of the processor system as an instruction stream is fed from pipeline stage 115 to pipeline stage 125 via logic elements 135 .
[0016] [0016]FIG. 2 illustrates a prior art processor system memory architecture 200 . The processor system memory architecture includes a plurality of data input/output devices 205 , 210 , 225 , interconnected to memory 220 , for providing data input to or accepting data output from memory 220 . Memory 220 includes syndrome logic (bit generator) 227 to perform error checking on the data paths (critical) leading to memory 220 using logic elements 215 (e.g., Exclusive-OR functions). Additionally, the memory architecture 200 includes correction logic 230 (e.g., error correction code—ECC), interconnected to data device 225 , to also perform error checking on the critical data paths using parity bits within the memory architecture 200 . Advantageously, a sufficient number of parity bits are added along the critical data paths by syndrome bit generator 227 and correction logic 230 to not only determine that there is an error, but to seamlessly correct the error as if it never occurred.
[0017] Processor system memory architecture 200 may include a large number of memory arrays including, but not limited to tags, register files, instruction caches, data caches, cache index tables, translation look-aside buffer tables (TLB), and dynamic random access memory (DRAM). Also, this error correction mechanism may be implemented entirely in software, a combination of hardware and software, or entirely in hardware.
[0018] [0018]FIG. 3 illustrates a prior art pipeline flush architecture 300 for a processor system. The pipeline flush architecture 300 includes a plurality of pipeline stages (P 1 -P 4 ) 305 , 315 , 325 , 335 , comprising one or more data input/output devices (e.g., functional units, flip-flops), interconnected by logic and memory elements 310 , 320 , 330 . The architecture 300 includes logic element 340 (e.g., NOR function) that outputs a flush signal 345 to trigger flushing and restarting of each pipeline stage in response to an error condition being detected. Advantageously, flush signal 345 is sent to each pipeline stage, interconnected by the clear (CLR) input of the data device for each stage, to trigger pipeline flushing and restarting of instruction processing.
[0019] Each pipeline stage 305 , 315 , 325 , 335 sends a separate signal input 341 , 342 , 343 , 344 to logic element 340 (e.g., NOR function) to enable flush signal 345 to flush and restart all pipeline stages when an error is detected. Exemplary error conditions include, but are not limited to a branch error 341 (e.g., error in program flow), access miss 342 , overflow condition 343 , and interrupt condition 344 . These error conditions may result from branch prediction logic errors, translation errors, or I/O device signaling.
[0020] [0020]FIG. 4 illustrates a prior art multiple processor system architecture 400 . The architecture includes processor cores (processor 1 , processor 2 ) 410 , 430 , both including a plurality (four) of pipeline stages 405 , 407 , 415 , 420 , and 435 , 440 , 445 , 450 , respectively. Advantageously, these pipeline stages may include fetching operations 405 , 435 , decoding operations 407 , 440 , execution operations 415 , 445 , and write-back operations 420 , 450 , respectively, as instructions are processed by the stages of the pipeline for both processors. Pipeline stages in both processors 410 , 430 are interconnected by a plurality of memory and logic elements 408 , 412 , 413 , and 438 , 442 , 448 , respectively.
[0021] During normal operation, both processors 410 , 440 will process the same instructions simultaneously. Advantageously, the processors 410 , 440 are connected in a functional redundancy check configuration where both processors execute the instruction stream on a clock by clock basis and compare the resulting architectural state updates (computed answers). The architecture 400 includes error detection logic 425 that is used to compare the architectural states resulting from instruction execution performed by processors 410 , 440 to detect if an error occurs. For example, processor 410 computes a load into register 1 (not shown) and processor 440 computes a load into register 2 (not shown). This detected error is ambiguous as a problem has been determined, but the system 400 cannot determine which architectural state is correct due to insufficient information. The functional redundancy check system 400 is able to detect these transient (occasional) errors after determining the final architectural state for each processor. A common transient error may result from a bit set being flipped during instruction processing.
[0022] [0022]FIG. 5 illustrates a pipeline logic architecture 500 for a multiple processor system in accordance with an embodiment of the present invention. The logic architecture 500 includes two processors cores (processor 1 , processor 2 ) 520 , 560 , both processors including a first pipeline stage 502 , 548 , and a succeeding pipeline stage 527 , 568 (pipeline stage +1). Both sets of pipeline stages 502 , 548 , and 527 , 568 include a plurality of data input/output devices (e.g, functional units, flip-flops) 505 , 525 , 550 , 570 for instruction processing (e.g., fetch, decode, etc.) during operation of the processing system. The sets of pipeline stages 502 , 548 , and 527 , 568 are interconnected by logic elements 515 , 565 that may perform a variety of logic operations (e.g., OR, AND, etc.) to facilitate operation of the processor system as an instruction stream is fed from the first pipeline stage 502 , 548 to the succeeding (second) pipeline stage 527 , 568 via logic elements 515 , 565 , respectively. Additionally, the logic architecture 500 further includes logic elements 528 , 575 interconnected to the succeeding (second) pipeline stage 527 , 568 , respectively, to facilitate interconnection to other succeeding pipeline stages (not shown) for instruction processing.
[0023] Advantageously, in accordance with embodiments of the present invention, the pipeline logic architecture 500 further includes parity bit generators 510 , 555 , and 540 , 545 for each set of pipeline stages 505 , 548 , and 527 , 568 respectively, for each processor 520 , 560 . For this exemplary embodiment, the parity bit generator (e.g., parity tree) generates three bits to use error detection during the each pipeline stage. Each parity bit generator 510 , 555 , 540 , 545 is intercoupled to the data input/output devices 505 , 550 , 525 , 570 along the instruction stream path for each pipeline stage to compute and generate a flush enabling signal. It is noted that three parity bits are used as an exemplary embodiment, and any number of parity bits may be used to detect errors for each pipeline stage.
[0024] The respective outputs from parity bit trees 510 , 555 (from the first pipeline stage for each processor) are fed to logic element 535 (e.g., Exclusive-OR function) to generate a flush signal 530 (flush stage 0) for the first pipeline stage 502 , 548 for each processor 520 , 560 , respectively. Similarly, the respective outputs from parity bit trees 540 , 545 (from the succeeding pipeline stage for each processor) are fed to logic element 580 (e.g., Exclusive-OR function) to generate a flush signal 585 (flush stage 1) for the succeeding (second) pipeline stage 527 , 568 for each processor 520 , 560 , respectively. For example, during operation a miscomparison of the parity bits (using logic elements 535 , 580 ) may be detected indicating an error condition in the respective pipeline stage to trigger a pipeline flush using flush signals 530 , 585 in combination with the logic described below in FIG. 6.
[0025] Advantageously, in accordance with embodiments of the present invention, the addition of the parity trees allow the internal logic (pipeline) states for each pipeline stage to be determined and verified. The data paths (non-critical) between multiple pipeline stages, along which the instruction stream is processed and executed, can now be checked for errors. The use of random logic along these non-critical data paths may allow randomly occurring soft (temporary) errors to occur during the pipeline stages of the processors (e.g., caused by exposure to cosmic rays and/or alpha particles).
[0026] [0026]FIG. 6 illustrates a pipeline flush architecture 600 for a multiple processor system. The pipeline flush architecture 600 includes two processor cores (processor 1 , processor 2 ), both processors including a plurality of pipeline stages (P 1 -P 4 ) 605 , 625 , 610 , 630 , 615 , 635 , and 620 , 640 , respectively. Advantageously, for example, these pipeline stages may include fetching operations 605 , 625 , decoding operations 610 , 630 , execution operations 615 , 635 , and write-back operations 620 , 640 , respectively, as instructions are processed by the stages of the pipeline for both processors. It is noted that these pipeline stage operations are solely exemplary and any set of pipeline stages may be used in accordance with embodiments of the present invention.
[0027] Each set of pipeline stages includes one or more data input/output devices (e.g., functional units, flip-flops), interconnected by logic and memory elements 609 , 629 , 613 , 636 , 618 , 651 . The architecture 600 includes logic elements 612 , 632 (e.g., Exclusive-OR function) that each output a flush signal (flush stage 0, flush stage 1) 604 , 638 for the first set 605 , 625 and succeeding (second) set of pipeline stages 610 , 630 , respectively, to trigger flushing and restarting of each pipeline stage (for each processor) in response to an error condition being detected.
[0028] Advantageously, in accordance with embodiments of the present invention, the pipeline flush architecture 600 further includes parity bit generators 608 , 628 , and 611 , 631 for the first two sets of pipeline stages 605 , 625 , and 610 , 630 , respectively, for each processor 602 , 621 . Each parity bit generator 608 , 628 , 611 , 631 is intercoupled to the data input/output devices for the first and second sets of pipeline stages 605 , 625 , 610 , 630 along the instruction stream path to help generate flush signals 604 , 638 . For example, during operation a miscomparison of the parity bits (using logic elements 612 , 632 ) may be detected indicating an error condition in the respective pipeline stage to trigger a pipeline flush using flush signals 604 , 638 in combination with the further logic in FIG. 6 described below.
[0029] Each logic element 612 , 632 receives as inputs the outputs generated from the parity trees 608 , 628 , and 611 , 631 , respectively, for the first and second set of pipeline stages 605 , 625 , 610 , 630 for each processor 602 , 621 : Output flush signals 604 , 638 are generated using the logic elements 612 , 632 in response to the outputs from the parity bit trees 608 , 628 , 611 , 631 .
[0030] The architecture 600 further includes logic elements 653 , 668 (e.g., NOR function) that output flush signals 655 , 670 , respectively, to trigger flushing and restarting of each set of pipeline stages in response to an error condition being detected (e.g., bits are flipped). Advantageously, flush signals 655 , 670 are sent to each set of pipeline stages, respectively, via interconnection by the clear (CLR) input of the data device for each stage, to trigger pipeline flushing and restarting in response to an error condition being detected.
[0031] During normal operation, both processors 602 , 621 will process the same instructions simultaneously. Advantageously, the processors 602 , 621 are connected in a functional redundancy check configuration where both processors execute the instruction stream on a clock by clock basis and compare the resulting architectural state updates (computed answers). The architecture 600 includes error detection logic 650 that is used to compare the architectural states resulting from instruction execution performed by processors 602 , 621 to detect if an error occurs.
[0032] Each set of pipeline stages 605 , 625 , 610 , 630 , 615 , 635 , 620 , 640 sends a separate signal input 641 , 642 , 643 , 644 , 604 , 638 , and 671 , 672 , 673 , 674 , 604 , 638 to logic elements 653 , 668 , respectively (e.g., NOR function) for both processors 602 , 621 to enable flush signals 655 , 670 to flush and restart all pipeline stages when an error condition is detected. The input signals 604 , 638 generated from the parity trees for the first two sets of stages are included in the flush enabling event signals sent to logic elements 653 , 668 to create a new flush enabling event, the detection of an error condition (miscomparison) within a pipeline stage using parity bit logic 608 , 628 , 611 , 631 and logic elements 612 , 632 . For example, to trigger a flush, a high logic signal (e.g., value of “1”) from any one of the inputs to logic elements 653 , 668 will output a low logic signal (e.g., value of “0”), using the NOR function, to form an enabling flush signal 655 , 670 to flush and restart all pipeline stages that may require a low-logic signal to initiate flushing of the pipeline stages.
[0033] Additionally, exemplary error conditions include, but are not limited to a branch error 644 , 674 (e.g., error in program flow), access miss 643 , 673 , overflow condition 642 , 672 , and interrupt condition 641 , 671 . These error conditions may result from branch prediction logic errors, translation errors, or I/O device signaling. It is noted that the use of a NOR function for logic elements 653 , 668 is solely exemplary and any combination of logic elements (using different logic functions) may be used to effectively trigger a flush for all pipeline stages.
[0034] Advantageously, in accordance with embodiments of the present invention, an error condition occurring in either of the first two sets of pipeline stages is detected (via the parity trees), a flush enabling signal for this event is generated, and an actual flush signal is output to clear all pipeline stages and restart the pipeline. It is noted that although only the first two sets of pipeline stages are shown in FIG. 6 to include parity bit trees for detecting errors within the stages, this illustration is exemplary and any number of pipeline stages may be designed with parity bit trees to detect error conditions that occur for that respective pipeline stage.
[0035] Advantageously, in accordance with embodiments of the present invention, the detection of a error condition (for the non-critical path) for the internal logic state of a pipeline stage defines a new flush event for a multiple processor system architecture. The new fault condition (“in flight error” being detected) is caused by the detection of a soft error that has not currently altered the architectural state. This new fault condition may be quickly detected during any stage of the pipeline using the new flush enabling signals generated to initiate flushing and restarting of the pipeline using the same or similar logic as for other flush-triggering faults.
[0036] It is noted that the flush logic indicated in FIG. 6, enabling a CLR (clear) operation for all data input/output devices (e.g., flip-flops), is solely exemplary, and other methods may be used for flushing the pipeline stages. The basic definition of a flush is to eliminate valid information from prior pipeline stages, and this may be accomplished via any number of methods. Instead of clearing all of the data in the pipeline, the flush signal may cause other remedial actions (changes). These other remedial actions include, but are not limited to, forcing the state of a few select signals to, for example, change an add instruction to a nop instruction or to set a valid flag to invalid. Flushing may also be accomplished by invalidating the operations of the current pipeline stage (that is requesting the flush) and continuing to request this flush for multiple cycles until the previous pipeline stages have drained all of their current operations. Any number of advantageous methods of ignoring pipelined operations while a flush event is being processed may be used, and these methods may depend on the logic and timing implications to the specific processor design being used.
[0037] In accordance with embodiments of the present invention, it is noted that the additional flush logic may be implemented on a machine-readable medium having stored thereon a plurality of executable instructions to perform the steps described herein.
[0038] In implementation of pipeline state error detection for a multiple processor system, the width (area of error detection coverage for the parity bit generators) of the needed parity bit tree is advantageously balanced between two extremes. The first extreme is to compare the flip-flop state between every flip-flop in both processors that is not covered by ECC syndrome logic. This implementation may be highly undesirable because it would require a large amount of wiring between the processors which would decrease the speed of the system. The second extreme is to generate a single parity bit from each processor. With this second implementation, a soft error caused by an alpha particle or cosmic ray hit could conceivably alter two adjacent flip-flops, and due to the nature of the exclusive or logic operation, an even number of bit changes would not be detected. Advantageously, an implementation in accordance with embodiments of the present invention can be processor design specific and can balance the needed inter-processor wiring with the needed redundancy of parity bits for these most extreme cases to be detected.
[0039] Advantageously, single bit or double bit errors may be detected and the pipelines of both processors subsequently flushed and restarted in accordance with embodiments of the present invention. Careful selection of the parity logic may be made to ensure that parity bits cannot alias to the same value if immediately adjacent logic gates are altered. Also, selection of a sufficient number of parity bits allows detection of any desired number of simultaneous bit errors. Variations may be made in the parity bit count, data field width, and maximum simultaneous bit error detection to achieve desired processor reliability. Since the probability of these errors (single event upsets), especially single bit errors, is very small (caused by radiation), flushing and restarting the pipelines greatly increases the likelihood that the program will run to error-free completion on the second attempt.
[0040] Robustness and reliability of the processors are improved by also potentially detecting timing and/or logic bugs (errors) that can cause complete processor failures. For processors advantageously connected in a functional redundancy check configuration, the logic design of the two processors can be nearly identical. However, the circuits of the processors can be required to be located at different locations on a chip and may, due to manufacturing variations, have subtle timing differences between the two processors. These timing differences can cause the two processors to diverge in their program flow, and the parity bits would most likely detect this divergence.
[0041] A consideration for implementation of embodiments of the present invention is to ensure that soft errors do not erroneously affect the additional flush logic conditions that have been defined by the pipeline (internal) state comparison. Various implementations may be used to make the flush logic robust and avoid false-flush events. One method that may be used is to implement the flush logic such that all reasonable errors to the error detection logic have the effect of triggering a pipeline flush. Because of the nature of pipeline flushes, it is good design practice to have a design tolerate random flushing events. Another method may use special circuit techniques to shield the check circuitry from error (upset) including making the checking circuitry physically large (thereby requiring that any radiation hit produce an abnormally large number of charge carriers), avoiding the use of domino logic, or other techniques for making the checking circuitry insensitive to error. Another alternative method may use parallel (multiple) flush detection where either flush detection circuit may trigger a flush. Advantageously, an inappropriately detected flush condition (false-flush) does not cause a failure.
[0042] Although the invention is primarily described herein using a two-processor, pipeline stage parity bit example, it will be appreciated by those skilled in the art that modifications and changes may be made without departing from the spirit and scope of the present invention. As such, the method and apparatus described herein may be equally applied to any multiple processor system that enables pipeline flushing and restarting in response to an error detected during any stage of the pipeline. | A method and system provides an increased robustness and protection against the occurrence of soft errors in parallel connect functional redundancy checking processors. This is achieved by predicting in advance the likely occurrence of a soft error and its impact on the resulting instruction flow and using already existing circuit implementations to hide the transient error. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a radiation system, a lithographic apparatus, a device manufacturing method, and a device manufactured thereby.
2. Description of the Related Art
A lithographic apparatus is a machine that applies a desired pattern onto a target portion of a substrate. Lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In that circumstance, a patterning device, such as a mask, may be used to generate a circuit pattern corresponding to an individual layer of the IC, and this pattern can be imaged onto a target portion (e.g. including part of one or several dies) on a substrate (e.g. a silicon wafer) that has a layer of radiation-sensitive material (resist). In general, a single substrate will contain a network of adjacent target portions that are successively exposed. Known lithographic apparatus include steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion in one go, and scanners, in which each target portion is irradiated by scanning the pattern through the beam of radiation in a given direction (the “scanning” direction) while synchronously scanning the substrate parallel or anti-parallel to this direction.
A lithographic apparatus as described above usually includes an illumination system and a radiation source. The radiation source provides the required radiation for irradiating the patterning device.
A problem in presently available EUV illumination systems is that non-linear effects occur when a high power EUV radiation beam is generated. These known illumination systems employ a radiation source with a laser produced plasma (LPP) or discharge produced plasma (DPP). Several problems are associated with radiation sources with a laser produced plasma when high power is involved: nozzle degradation, nozzle material sputtering, nozzle thermal load, gas recycling, vacuum system gas load, low repetition rate, low conversion efficiency, inhomogeneous emission profiles, etc. Current problems with discharge produced plasma at higher powers are: extended source size, elongated shape of the radiation source, pinch size depending on all system parameters, low conversion efficiency, etc.
SUMMARY OF THE INVENTION
Some of the benefits of the present invention are that a radiation system can be provided that has, amongst other things, a relatively large yield, generates a reduced amount of out-of-band radiation and a reduced amount of fast particles that may sputter entities (e.g. optical systems) positioned downstream of the radiation system, than is presently available.
It is possible to multiplex radiation, as disclosed for example in European Patent Application 03255825.6, filed Sep. 17, 2003 in the name of the applicant, the entire contents of which are incorporated by reference.
One aspect of the present invention relates to a system for multiplexing radiation, the radiation system including a first radiation source configured to provide radiation and a second radiation source configured to provide radiation. It is suitable for EUV radiation sources, but is not restricted thereto.
The system of the present invention in one embodiment includes an optical member with a first reflecting surface and a second reflecting surface. The first reflecting surface is configured to receive a first amount of radiation from the first radiation source and reflect the first amount and the second reflecting surface is configured to receive a second amount of radiation from the second radiation source and reflect the second amount. As it possible to employ smaller sources, a reduction of strongly non-linear effects per individual source is obtained. Additionally, the smaller sources may run at low pulse energy and peak power. The active volume of these sources is comparable to larger sources. Smaller sources allow for a more controlled and more stable operation. Problems in connection with thermal dissipation and heat removal and transportation management are reduced. The same holds for problems in connection with delivery of source gases, power, electrode erosion and system contamination. The first source and the second source will generate in total less particles and cause less sputtering of downstream optical components compared to one bigger radiation source after power scale up. Less alignment is necessary for the member compared to individual mirrors.
In an embodiment of the present invention, the optical member includes a conical shape or a polygonal shaped cross-section. Such a member may be made with a precision workbench. Such a member is at the same time both robust and simple.
In a further embodiment, at least one of the first reflecting surface and the second reflecting surface is positioned at grazing incidence with the first amount and the second amount, respectively. Such an arrangement makes the invention suitable for use in connection with (E)UV radiation.
In a further embodiment, the first radiation source is configured to be operated substantially simultaneously with the second radiation source. This enables spatial multiplexing of radiation and a more homogeneously filled aperture.
In a further embodiment, the first radiation source is configured to be operated alternately with the second radiation source. This provides a more stable output in time and effectively a higher pulse frequency. It makes the multiplexing of radiation in the time domain possible.
In a further embodiment, at least one of the first radiation source and the second radiation source includes an electrical discharge plasma, a Z pinch discharge plasma, a discharge produced plasma (DPP), a laser produced plasma (LPP) and a dense plasma focus, an ultraviolet (UV) radiation source, an extreme ultra-violet (EUV) radiation source, an X-ray radiation source, a radiation source generating particle beams, a radiation source generating ion beams, or a radiation source generating electron beams. These are readily available (E)UV sources.
In a further embodiment, at least one of the first reflecting surface and the second reflecting surface includes a spectral purity filter, a surface coating, a grating, or a specific absorption and diffraction structure. In this way the reflecting surface reflect and perform at the same time another function, for example filtering and/or absorbing.
In a further embodiment, at least one of the first reflecting surface and the second reflecting surface is curved. The curvature of the reflecting surfaces makes manipulation i.e. increase or decrease of the cross section of the radiation beam from the respective sources, possible.
The invention also relates to a lithographic apparatus including a system as described above.
The invention also relates to a device manufacturing method including providing a beam of radiation of radiation as described above; patterning the beam of radiation with a pattern in its cross-section; and projecting the patterned beam of radiation onto a target portion of a substrate.
Although specific reference may be made in this text to the use of lithographic apparatus in the manufacture of ICs, it should be understood that the lithographic apparatus described herein may have other applications, such as the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, liquid-crystal displays (LCDs), thin-film magnetic heads, etc. It should be appreciated that, in the context of such alternative applications, any use of the terms “wafer” or “die” herein may be considered as synonymous with the more general terms “substrate” or “target portion”, respectively. The substrate referred to herein may be processed, before or after exposure, in for example a track (a tool that typically applies a layer of resist to a substrate and develops the exposed resist) or a metrology or inspection tool. Where applicable, the disclosure herein may be applied to such and other substrate processing tools. Further, the substrate may be processed more than once, for example in order to create a multi-layer IC, so that the term substrate used herein may also refer to a substrate that already contains multiple processed layers.
The terms “radiation” and “beam” used herein encompass all types of electromagnetic radiation, including ultraviolet (UV) radiation (e.g. having a wavelength of 365, 248, 193, 157 or 126 nm) and extreme ultra-violet (EUV) radiation (e.g. having a wavelength in the range of 5-20 nm), as well as X-ray radiation and particle beams, such as ion beams or electron beams.
The term “patterning device” used herein should be broadly interpreted as referring to a device that can be used to impart a beam of radiation with a pattern in its cross-section such as to create a pattern in a target portion of the substrate. It should be noted that the pattern imparted to the beam of radiation may not exactly correspond to the desired pattern in the target portion of the substrate. Generally, the pattern imparted to the beam of radiation will correspond to a particular functional layer in a device being created in the target portion, such as an integrated circuit.
Patterning device may be transmissive or reflective. Examples of patterning device include masks, programmable mirror arrays, and programmable LCD panels. Masks are well known in lithography, and include mask types such as binary, alternating phase-shift, and attenuated phase-shift, as well as various hybrid mask types. An example of a programmable mirror array employs a matrix arrangement of small mirrors, each of which can be individually tilted so as to reflect an incoming radiation beam in different directions; in this manner, the reflected beam is patterned.
The support supports, e.g. bares the weight of, the patterning device. It holds the patterning device in a way depending on the orientation of the patterning device, the design of the lithographic apparatus, and other conditions, for example whether or not the patterning device is held in a vacuum environment. The support may use mechanical clamping, vacuum, or other clamping techniques, for example electrostatic clamping under vacuum conditions. The support may be a frame or a table, for example, which may be fixed or movable as required and which may ensure that the patterning device is at a desired position, for example with respect to the projection system. Any use of the terms “reticle” or “mask” herein may be considered synonymous with the more general term “patterning device”.
The term “projection system” used herein should be broadly interpreted as encompassing various types of projection system, including refractive optical systems, reflective optical systems, and catadioptric optical systems, as appropriate for example for the exposure radiation being used, or for other factors such as the use of an immersion fluid or the use of a vacuum. Any use of the term “lens” herein may be considered as synonymous with the more general term “projection system”.
The illumination system may also encompass various types of optical components, including refractive, reflective, and catadioptric optical components for directing, shaping, or controlling the beam of radiation of radiation, and such components may also be referred to below, collectively or singularly, as a “lens”.
The lithographic apparatus may be of a type having two (dual stage) or more substrate tables (and/or two or more mask tables). In such “multiple stage” machines the additional tables may be used in parallel, or preparatory steps may be carried out on one or more tables while one or more other tables are being used for exposure.
The lithographic apparatus may also be of a type wherein the substrate is immersed in a liquid having a relatively high refractive index, e.g. water, so as to fill a space between the final element of the projection system and the substrate. Immersion liquids may also be applied to other spaces in the lithographic apparatus, for example, between the mask and the first element of the projection system. Immersion techniques are well known in the art for increasing the numerical aperture of projection systems.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention 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:
FIG. 1 depicts a lithographic apparatus according to an embodiment of the present invention;
FIG. 2 depicts a system for multiplexing radiation according to an embodiment of the present invention;
FIG. 3 shows a cross-section along line III-III shown in FIG. 2 .
DETAILED DESCRIPTION
FIG. 1 schematically depicts a lithographic apparatus according to a particular embodiment of the invention. The apparatus includes an illumination system (illuminator) IL configured to provide a beam of radiation PB of radiation (e.g. UV or EUV radiation). A support (e.g. a mask table) MT is configured to support a patterning device (e.g. a mask) MA and is connected to a first positioning device PM that accurately positions the patterning device with respect to a projection system PS. A substrate table (e.g. a wafer table) WT is configured to hold a substrate (e.g. a resist-coated wafer) W and is connected to second positioning device PW that accurately positions the substrate with respect to the projection system PS. The projection system (e.g. a reflective projection lens) PS is configured to image a pattern imparted to the beam of radiation PB by patterning device MA onto a target portion C (e.g. including one or more dies) of the substrate W.
As here depicted, the apparatus is of a reflective type (e.g. employing a reflective mask or a programmable mirror array of a type as referred to above). Alternatively, the apparatus may be of a transmissive type (e.g. employing a transmissive mask).
The illuminator IL receives radiation from a radiation source SO. The source and the lithographic apparatus may be separate entities, for example when the source is a plasma discharge source. In such cases, the source is not considered to form part of the lithographic apparatus and the radiation is generally passed from the source SO to the illuminator IL with the aid of a radiation collector including, for example, suitable collecting mirrors and/or a spectral purity filter. In other cases the source may be integral part of the apparatus, for example when the source is a mercury lamp. The source SO and the illuminator IL may be referred to as a radiation system.
The illuminator IL may include an adjusting device(s) to adjust the angular intensity distribution of the beam. Generally, at least the outer and/or inner radial extent (commonly referred to as σ-outer and σ-inner, respectively) of the intensity distribution in a pupil plane of the illuminator can be adjusted. The illuminator provides a conditioned beam of radiation PB having a desired uniformity and intensity distribution in its cross-section.
The beam of radiation PB is incident on the mask MA, which is held on the mask table MT. Being reflected by the mask MA, the beam of radiation PB passes through the projection system PS, which focuses the beam onto a target portion C of the substrate W. With the aid of the second positioning device PW and a position sensor IF 2 (e.g. an interferometric device), the substrate table WT can be moved accurately, e.g. so as to position different target portions C in the path of the beam PB. Similarly, the first positioning device PM and a position sensor IF 1 (e.g. an interferometric device) can be used to accurately position the mask MA with respect to the path of the beam PB, e.g. after mechanical retrieval from a mask library, or during a scan. In general, movement of the object tables MT and WT will be realized with the aid of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which form part of the positioning devices PM and PW. However, in the case of a stepper, as opposed to a scanner, the mask table MT may be connected to a short stroke actuator only, or may be fixed. Mask MA and substrate W may be aligned using mask alignment marks M 1 , M 2 and substrate alignment marks P 1 , P 2 .
The depicted apparatus can be used in the following preferred modes:
1. In step mode, the mask table MT and the substrate table WT are kept essentially stationary, while an entire pattern imparted to the beam of radiation is projected onto a target portion C at once (i.e. a single static exposure). The substrate table WT is then shifted in the X and/or Y direction so that a different target portion C can be exposed. In step mode, the maximum size of the exposure field limits the size of the target portion C imaged in a single static exposure.
2. In scan mode, the mask table MT and the substrate table WT are scanned synchronously while a pattern imparted to the beam of radiation is projected onto a target portion C (i.e. a single dynamic exposure). The velocity and direction of the substrate table WT relative to the mask table MT is determined by the (de-)magnification and image reversal characteristics of the projection system PL. In scan mode, the maximum size of the exposure field limits the width (in the non-scanning direction) of the target portion in a single dynamic exposure, whereas the length of the scanning motion determines the height (in the scanning direction) of the target portion.
3. In another mode, the mask table MT is kept essentially stationary holding a programmable patterning device, and the substrate table WT is moved or scanned while a pattern imparted to the beam of radiation is projected onto a target portion C. In this mode, generally a pulsed radiation source is employed and the programmable patterning device is updated as required after each movement of the substrate table WT or in between successive radiation pulses during a scan. This mode of operation can be readily applied to maskless lithography that utilizes programmable patterning device, such as a programmable mirror array of a type as referred to above.
Referring to FIG. 2 , radiation is multiplexed in the source SO. Radiation of radiation sub-sources is combined into one composite radiation beam. The source SO will therefore include several radiation sub-sources. In FIG. 2 , for purpose of illustration, only a radiation sub-source 3 and a radiation sub-source 5 are shown. The present invention, however, is not limited to a source SO with only two radiation sub-sources. In the vicinity of the radiation sub-source 3 , a collector 7 is present. In the vicinity of the radiation sub-source 5 , a collector 9 is present. The collector 7 and the collector 9 as shown in FIG. 2 are parabolic. The radiation sub-source 3 and the radiation sub-source 5 , respectively, may be located in the focal point of the respective collectors 7 and 9 . In this case, the radiation form the respective radiation sub-sources 3 and 5 will emerge parallel as long as it hits the respective collectors 7 and 9 . As an example, a beam 18 that does not hit the collector 9 is shown in FIG. 2 . The radiation power of this beam 18 does not contribute to the amount of radiation power of the combined composite beam, as discussed below. It should be appreciated that differently shaped collectors e.g. elliptical, circular or else are also possible. Radiation, in particular extreme ultra violet (EUV) radiation, emanates from the radiation sub-source 3 and from the radiation sub-source 5 . The source SO further includes a member 15 with two reflecting surfaces 17 , 19 , respectively. Note that, when there are more than two sub-sources 3 , 5 there will, generally, be more than two reflecting surfaces 17 , 19 . A beam of radiation 11 as produced by radiation sub-source 3 upstream from the reflective surface 17 is referred to with reference numeral 11 a and downstream from the reflective surface 17 with reference numeral 11 b . A beam of radiation 13 as produced by radiation sub-source 5 upstream from the reflective surface 19 is referred to with reference numeral 13 a and downstream from the reflective surface 19 with reference numeral 13 b . The beams 11 b , 13 b may impinge on an optical system 21 .
The source SO according to this embodiment functions in the following way. The radiation sub-source 3 and the radiation sub-source 5 , respectively, direct divergent radiation to the parabolic collectors 7 and 9 , respectively. At least some part of the radiation emanates from the reflective surface 17 and 19 , respectively, as a beam of radiation 11 a and 13 a , respectively, that is parallel, if the radiation sub-sources 3 and 5 respectively are located in the focal points of the parabolical collectors 7 and 9 , respectively. The beams 11 a and 13 a , respectively, are reflected by the reflective surfaces 17 and 19 , respectively, and two mutually parallel beams 11 b and 13 b result. The combined power of the beams 11 b and 13 b may be supplied subsequently to the optical system 21 downstream. Such an optical system 21 may be an integrator that has an integrating function such that a single radiation beam is formed and used to project a pattern on patterning device to a substrate. Alternatively, a fly-eye scrambler may be present as the optical system 21 to mix the signature of the individual sub-sources 3 and 5 such that uniform radiation density is obtained in time and space before the beam enters the illuminator IL.
Although this embodiment has been described for parallel beams 11 b and 13 b of radiation, this embodiment covers the case in which the beams 11 b and 13 b are not parallel after reflection from the reflective member 15 , for example beams that converge into a focus. Also, one or both of the radiation sources 3 and 5 may not be located in the focal points of the parabolic collectors 7 or 9 . Then the beams of radiation 11 a and/or 13 a will be divergent and/or convergent in character. This embodiment covers these cases as well.
The reflective member 15 may be of a conical shape. An advantage is that such conically shaped objects are easily produced by mechanical workbenches. In addition, the member 15 may also include a polygonal shaped cross-section.
The source SO can be used with all types of electromagnetic radiation. When this source SO is used in connection with radiation in the EUV range of the electromagnetic spectrum, it is recommended to let the beams of radiation 11 a , 13 a impinge under grazing incidence on the reflective surfaces 17 , 19 . This means that the angle with respect to surface 17 , 19 is as small as possible. The reflection in this case will be the biggest and the absorption the smallest. Normally, the radiation sources 3 and 5 will be incoherent. However, when the radiation sources are coherent, both peak values and focussing will be enhanced by interference.
FIG. 3 is a view along the line III-III in FIG. 2 of a combined beam of radiation filling an aperture 31 . The combined beam includes the beams 11 b and 13 b shown in FIG. 2 . An additional beam 33 and an additional beam 34 may be present. These additional beams 33 , 34 are drawn with a dashed line in FIG. 3 . These additional beams 33 , 34 may be provided by other radiation sources (not shown). By operating the various radiation sources at the same time, the combined power of the separate radiation sources is imparted to the aperture 31 .
Radiation sources providing EUV radiation are generally pulsed. As an alternative to the embodiments described above, a composite radiation source with an increased frequency may be obtained by operating the radiation sources on a one by one basis. In this case, for example, the radiation sources providing the beams of radiation 13 b , 33 , 11 b and 34 are operated one-by-one in time. This provides a partly filled aperture 31 at any moment in time, however, at an increased frequency. Then, the optical system 21 may be a scrambler arranged to scramble the optical power over the aperture 31 .
The radiation sources used in the present invention may be anyone of the several plasma based radiation sources that are regularly available, for example: an electrical discharge plasma, a Z pinch discharge plasma, a discharge produced plasma (DPP), a laser produced plasma (LPP) and a dense plasma focus.
The reflecting surfaces 17 and 19 shown in FIG. 2 may, apart from combining optical power, at the same time perform an additional function. To illustrate the previous point, the reflective surface 17 may, as an example, in addition be coated with a substance that filters a particular wavelength (range) out of the radiation that is incident on it. Similar considerations of course hold for the reflective surface 19 and further reflective surfaces that may be present on the reflective member 15 . Besides a spectral purity filter also a surface coating, a grating, or a specific absorption and diffraction structure may be present on the member 15 . Filtering reflective surfaces are, e.g. described in European Patent Application 03078495.3, filed Nov. 6, 2003 in the name of the applicant, the contents of which are incorporated by reference.
It is also possible for the reflecting surface 17 and 19 to be curved. In this way, a beam of radiation that impinges on these surfaces will, after reflection on these reflecting surfaces 17 , 19 , be more convergent in character (for concave surfaces 17 , 19 ) or be more divergent (for convex surfaces 17 , 19 ) depending on the particular curvature of the respective surface.
The source SO may direct the combined beam of radiation to a further optical system 21 located downstream of the source SO. This optical system 21 may be a scrambler or an integrator, as discussed above.
Although the present invention has been described in the above in connection with the use of (extreme) ultraviolet radiation, the present invention is not limited to the use of this type of radiation. Other types of radiation may be contemplated. For example, visible radiation or infra red (IR) or X-ray radiation or radiation including particle beams may be used.
Combinations and/or variations on the above described modes of use or entirely different modes of use may also be employed. | A radiation system for multiplexing radiation includes two radiation sub-sources. The sub-sources each provide a certain amount of radiation. The system further includes a member with reflecting surfaces. The surfaces are arranged in such a way that they receive the radiation from the sub-sources and combine this radiation. The radiation sub-sources may operate simultaneously or alternately. The surfaces may perform functions such as filtering or (de)magnifying. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to Japanese Patent Application No. 2012-055104 filed Mar. 12, 2012, the content of which is hereby incorporated herein by reference.
BACKGROUND
The present disclosure relates to a sewing machine and a non-transitory computer-readable medium storing a sewing machine control program that allow sewing in a position specified on a work cloth.
A sewing machine is known that can easily set a sewing position and a sewing angle, at which a desired embroidery pattern is to be sewn, on a work cloth. For example, a known sewing machine includes an imaging portion. After a user affixes a marker to a specified position on the work cloth, an image of the marker may be captured by the imaging portion. The sewing machine may automatically set the sewing position and the sewing angle of the embroidery pattern based on the captured image of the marker.
SUMMARY
However, with the above-described sewing machine, it may be necessary to affix the marker to the work cloth. Further, after the sewing machine has set the sewing position and the sewing angle of the embroidery pattern, the user may need to remove the marker affixed to the work cloth before sewing is performed. Therefore, the operation may be troublesome for the user.
Embodiments of the broad principles derived herein provide a sewing machine and a non-transitory computer-readable medium storing a sewing machine control program that enable easily setting a position, on a work cloth, at which sewing is performed.
Embodiments provide a sewing machine that includes at least one ultrasonic wave detecting portion, a thickness detecting portion, a processor, and a memory. The at least one ultrasonic wave detecting portion is configured to detect an ultrasonic wave. The thickness detecting portion is configured to detect a thickness of a work cloth. The memory is configured to store computer-readable instructions that instruct the sewing machine to execute a step that includes identifying a position, on the work cloth, of a transmission source of the ultrasonic wave, based on information pertaining to the ultrasonic wave that has been detected by the at least one ultrasonic wave detecting portion and on the thickness that has been detected by the thickness detecting portion. The memory is also configured to store computer-readable instructions that instruct the sewing machine to execute a step that includes controlling sewing on the work cloth based on the position of the transmission source that has been identified.
Embodiments also provide a non-transitory computer-readable medium storing a control program executable on a sewing machine. The program includes computer-readable instructions, when executed, to cause the sewing machine to perform the step of identifying a position, on a work cloth, of a transmission source of the ultrasonic wave, based on information pertaining to a ultrasonic wave that has been detected by at least one ultrasonic wave detecting portion of the sewing machine and on a thickness that has been detected by a thickness detecting portion of the sewing machine, the at least one ultrasonic wave detecting portion being configured to detect the ultrasonic wave, and the thickness detecting portion being configured to detect the thickness of the work cloth. The program further includes computer-readable instructions, when executed, to cause the sewing machine to perform the step of controlling sewing on the work cloth based on the position of the transmission source that has been identified.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments will be described below in detail with reference to the accompanying drawings in which:
FIG. 1 is a front view of a sewing machine;
FIG. 2 is a front view of a presser foot lifting mechanism in a state in which the presser foot is separated from a work cloth;
FIG. 3 is a front view of the presser foot lifting mechanism in a state in which the presser foot is pressing the work cloth;
FIG. 4 is a perspective view of a receiver;
FIG. 5 is a front view of the receiver;
FIG. 6 is a cross-sectional view of the receiver taken along a line I-I shown in FIG. 5 , as seen in an arrow direction;
FIG. 7 is a block diagram showing an electrical configuration of the sewing machine and an ultrasonic pen;
FIG. 8 is a plan view of the work cloth that is placed on a needle plate, showing positional relationships of respective coordinates in order to illustrate a method of calculating specified coordinates E;
FIG. 9 is a flowchart showing first main processing;
FIG. 10 is a front view of a sewing machine according to a second embodiment;
FIG. 11 is a block diagram showing an electrical configuration of the sewing machine and an ultrasonic pen according to the second embodiment;
FIG. 12 is a plan view of the work cloth that is placed on a needle plate, showing positional relationships of respective coordinates in order to illustrate a method of calculating specified coordinates E according to the second embodiment; and
FIG. 13 is a flowchart showing second main processing according to the second embodiment.
DETAILED DESCRIPTION
Hereinafter, an embodiment will be explained with reference to the appended drawings. First, a physical structure of a sewing machine 1 will be explained with reference to FIG. 1 . In the following explanation, the near side, the far side, the upper side, the lower side, the left side, and the right side of FIG. 1 are respectively defined as the front side, the rear side, the upper side, the lower side, the left side, and the right side of the sewing machine 1 . In other words, a direction in which a pillar 12 , which will be explained below, extends is the up-down direction of the sewing machine 1 . A longitudinal direction of a bed 11 and an arm 13 is the left-right direction of the sewing machine 1 . A surface on which a switch cluster 21 is arranged is the front surface of the sewing machine 1 .
As shown in FIG. 1 , the sewing machine 1 includes the bed 11 , the pillar 12 , the arm 13 , and a head 14 . The bed 11 is longer in the left-right direction. The pillar 12 extends upward from the right end of the bed 11 . The arm 13 extends to the left from the upper end of the pillar 12 . The head 14 is provided on the left side of the arm 13 . The bed 11 is provided with a needle plate 22 (refer to FIG. 2 ), a feed dog 34 , a cloth feed mechanism (not shown in the drawings), a feed adjustment motor 83 (refer to FIG. 7 ), and a shuttle mechanism (not shown in the drawings). The needle plate 22 is disposed on an upper surface of the bed 11 . The feed dog 34 is provided under the needle plate 22 and may feed, by a specified feed distance, a work cloth 100 (refer to FIG. 2 ) on which sewing is performed. The cloth feed mechanism may drive the feed dog 34 . The feed adjustment motor 83 may adjust the feed distance. The head 14 is provided with a needle bar mechanism (not shown in the drawings), a needle bar swinging motor 80 (refer to FIG. 7 ), and a thread take-up mechanism (not shown in the drawings). The needle bar mechanism may move a needle bar (not shown in the drawings) in the up-down direction. A sewing needle 29 may be attached to the needle bar. The needle bar swinging motor 80 may swing the needle bar in the left-right direction. Two receivers 94 and 95 are provided on the rear portion of the lower edge of the head 14 such that the receivers 94 and 95 are separated to the left and to the right. The receivers 94 and 95 are configured to detect an ultrasonic wave transmitted by an ultrasonic pen 91 (to be explained below). It is assumed that the upper surface of the bed 11 and an upper surface of the needle plate 22 are substantially the same height.
A vertically rectangular liquid crystal display 15 is provided on the front face of the pillar 12 . For example, keys that are used to execute various functions necessary to the sewing operation, various messages, and various patterns etc. are displayed on the liquid crystal display 15 .
A transparent touch panel 26 is provided in the upper surface (front surface) of the liquid crystal display 15 . A user may perform an operation of pressing the touch panel 26 , using a finger or a dedicated touch pen, in a position corresponding to one of the various keys or the like displayed on the liquid crystal display 15 . This operation is hereinafter referred to as a “panel operation.” The touch panel 26 detects the position pressed by the finger or the dedicated touch pen etc., and the sewing machine 1 (more specifically, a CPU 61 to be described below) determines an item corresponding to the detected position. In this way, the sewing machine 1 recognizes the selected item. By performing the panel operation, the user can perform pattern selection and various settings etc.
Connectors 39 and 40 are provided in the right face of the pillar 12 . An external storage device (not shown in the drawings), such as a memory card, can be connected to the connector 39 . Via the connector 39 , the sewing machine 1 can read pattern data and various programs into the sewing machine 1 from the external storage device, and can output pattern data and various programs to the outside of the sewing machine 1 . A connector 916 may be connected to the connector 40 . The connector 916 is provided on an end of a cable 915 that extends from the ultrasonic pen 91 (to be explained below). Via the connector 40 , the sewing machine 1 may supply electric power to the ultrasonic pen 91 and may detect various signals (a transmission start signal etc. that will be explained below) output from the ultrasonic pen 91 .
The structure of the arm 13 will be explained. A cover 16 is attached to the upper portion of the arm 13 . The cover 16 is provided in the longitudinal direction of the arm 13 . The cover 16 is supported such that the cover 16 can be opened and closed by being rotated about an axis that extends in the left-right direction at the upper rear edge of the arm 13 . A thread spool pin (not shown in the drawings) is provided underneath the cover 16 in the interior of the arm 13 . A thread spool may be mounted on the thread spool pin. A thread spool may supply a thread to the sewing machine 1 . Although not shown in the drawings, an upper thread that extends from the thread spool may be supplied to the sewing needle 29 that is attached to the needle bar, via a tensioner, a thread take-up spring, and a thread take-up lever, which are provided on the head 14 .
A sewing machine motor 79 (refer to FIG. 7 ) is provided in the arm 13 . The sewing machine motor 79 may rotate a drive shaft (not shown in the drawings), which extends in the longitudinal direction of the arm 13 . The needle bar mechanism and the thread take-up mechanism are driven by the rotation of the drive shaft.
The switch cluster 21 is provided in a lower portion of the front face of the arm 13 . The switch cluster 21 includes a sewing start/stop switch, a reverse stitch switch, a needle up/down switch, and a presser foot up/down switch, and the like.
A presser bar 52 (refer to FIG. 2 ) and a presser foot lifting mechanism 20 are disposed to the rear of the needle bar. The presser foot lifting mechanism 20 may move the presser bar 52 in the up-down direction. A presser foot 30 may be detachably (replaceably) attached to the lower end of the presser bar 52 . The presser foot 30 may apply pressure to the work cloth 100 .
A structure of the presser foot lifting mechanism 20 will be explained with reference to FIG. 2 and FIG. 3 . The presser foot lifting mechanism 20 includes the presser bar 52 , the presser foot 30 , a rack member 54 , a retaining ring 55 , a presser foot lifting motor 56 , a drive gear 561 , an intermediate gear 57 , a pinion 58 , a presser bar guide bracket 59 , a presser bar spring 53 , a presser lifting lever 50 , and a potentiometer 51 .
The presser bar 52 extends in the up-down direction. The presser bar 52 is supported by a sewing machine frame (not shown in the drawings) such that the presser bar 52 can be moved in the up-down direction. The rack member 54 has a toothed portion that meshes with the pinion 58 that will be explained below. The rack member 54 is provided around the upper end portion of the presser bar 52 such that the rack member 54 can be slid. The retaining ring 55 is fixed to the upper end of the presser bar 52 . The presser bar guide bracket 59 is fixed substantially in the center, in the up-down direction, of the presser bar 52 . The presser bar spring 53 is provided around the presser bar 52 in a position where the presser bar spring 53 is sandwiched between the rack member 54 and the presser bar guide bracket 59 . The presser foot lifting motor 56 is fixed to the sewing machine frame in a position to the right of the rack member 54 . The drive gear 561 is fixed to an output shaft of the presser foot lifting motor 56 . The drive gear 561 rotates integrally with the output shaft. The intermediate gear 57 is rotatably supported by the sewing machine frame. The intermediate gear 57 meshes with the drive gear 561 and may rotate in accordance with the rotation of the drive gear 561 . The pinion 58 is formed integrally with the intermediate gear 57 . The pinion 58 meshes with the toothed portion of the rack member 54 .
A case is considered in which the presser foot lifting motor 56 is driven and the drive gear 561 is rotated in the counter-clockwise direction. In this case, the rotation of the drive gear 561 is transmitted to the intermediate gear 57 and the pinion 58 , and the rack member 54 is moved upward. As shown in FIG. 2 , when the rack member 54 is moved upward, the upper end surface of the rack member 54 comes into contact with the retaining ring 55 , which is fixed to the upper end of the presser bar 52 . As a result of this, the presser bar 52 is raised and the presser foot 30 is also raised. A case is considered in which the presser foot lifting motor 56 is driven and the drive gear 561 is rotated in the clockwise direction, from a state in which the presser foot 30 is raised (refer to FIG. 2 ). In this case, the rack member 54 is moved downward and the presser bar spring 53 that is in contact with the lower end surface of the rack member 54 is depressed downward, as shown in FIG. 3 . As a result of this, the presser bar guide bracket 59 is depressed downward, and the presser foot 30 may press the work cloth 100 that is placed on the needle plate 22 downward.
The presser lifting lever 50 is a known lever that is used when an operation (a manual operation by the user) to raise or lower the presser bar 52 is performed independently of the up-down movement (the raising and lowering) of the presser bar 52 by the presser foot lifting motor 56 . Although not explained in detail, the presser lifting lever 50 is pivotally supported by the sewing machine frame such that the presser lifting lever 50 can be swung. In accordance with the raising and lowering operation of the presser lifting lever 50 , the presser lifting lever 50 may come into contact, from underneath, with the presser bar guide bracket 59 , and the presser bar 52 may thus be moved in the up-down direction.
The potentiometer 51 is provided on the left side of the presser bar 52 . The potentiometer 51 is a rotary potentiometer. Based on a resistance value that changes depending on an amount of rotation of the potentiometer 51 , the potentiometer 51 may detect a vertical position (a height position) of the presser bar 52 . A lever 511 , which extends to the right, is provided on a rotating shaft of the potentiometer 51 . The leading end of the lever 511 is in contact with an upper surface of a protruding portion 591 , which protrudes to the left of the presser bar guide bracket 59 . The leading end of the lever 511 is constantly biased to be in contact with the upper surface of the protruding portion 591 by a coil spring that is not shown in the drawings.
The lever 511 rotates when the presser bar guide bracket 59 is moved in the up-down direction. As a result, the resistance value of the potentiometer 51 changes in accordance with an angle of rotation of the lever 511 . The CPU 61 (refer to FIG. 7 ), which will be explained below, detects the vertical position of the presser bar 52 (the presser foot 30 ) based on a voltage that corresponds to the resistance value. Here, a position of the presser foot 30 when there is no work cloth 100 , namely, a position in which the presser foot 30 is in contact with the upper surface of the needle plate 22 , is taken as a reference position. The voltage corresponding to the resistance value of the potentiometer 51 when the presser foot 30 is in the reference position is set as a reference value by the CPU 61 . The CPU 61 detects the height position of the presser foot 30 by comparing the reference value with a voltage corresponding to the resistance value of the potentiometer 51 in a state in which the presser foot 30 is pressing the work cloth 100 . By detecting the height position of the presser foot 30 in this way, the CPU 61 can accurately detect the thickness of the work cloth 100 .
The ultrasonic pen 91 will be explained with reference to FIG. 1 . For example, the user may use the ultrasonic pen 91 to specify a position on which sewing is to be performed on the work cloth 100 . The sewing machine 1 may identify the position specified by the user based on the ultrasonic wave transmitted from the ultrasonic pen 91 and on the transmission start signal (to be explained below), and may perform sewing in the specified position.
A pen tip 911 is provided at the leading end of the ultrasonic pen 91 . The pen tip 911 can be moved toward the inside of a pen body of the ultrasonic pen 91 (in the rearward direction of the ultrasonic pen 91 ). Normally, the pen tip 911 is in a protruding position in which the pen tip 911 protrudes slightly to the outside from the pen body. When a force acts on the pen tip 911 in the rearward direction, the pen tip 911 enters into the pen body. When the force acting on the pen tip 911 is released, the pen tip 911 returns to the original protruding position. An electric substrate (not shown in the drawings) is provided in the interior of the ultrasonic pen 91 . The electric substrate may be connected to a control portion 60 (refer to FIG. 7 ) of the sewing machine 1 , via the cable 915 that extends from the rear end of the ultrasonic pen 91 .
A switch 912 , an ultrasonic transmitter 913 , and a signal output circuit 914 etc. are mounted on the electric substrate (refer to FIG. 7 ). The switch 912 is provided facing the rear end of the pen tip 911 . The ultrasonic transmitter 913 is an ultrasonic wave transmission source. The ultrasonic transmitter 913 transmits an ultrasonic wave when the switch 912 is pressed. The ultrasonic transmitter 913 is provided in a position that is extremely close to the pen tip 911 . The signal output circuit 914 normally outputs a High signal to the sewing machine 1 via the cable 915 . Then, when the switch 912 is pressed, the signal output circuit 914 outputs a Low signal to the sewing machine 1 via the cable 915 . An output timing of the Low signal is the same timing as the transmission of the ultrasonic wave by the ultrasonic transmitter 913 . Namely, the Low signal is a signal (hereinafter referred to as the “transmission start signal”) that indicates that the transmission of the ultrasonic wave by the ultrasonic transmitter 913 has started. The signal output circuit 914 notifies the sewing machine 1 of the timing at which the ultrasonic wave is transmitted by the ultrasonic transmitter 913 by outputting the transmission start signal in this way.
When the user holds the ultrasonic pen 91 with the user's hand and causes the pen tip 911 to touch a given position on the work cloth 100 , the pen tip 911 is moved in the rearward direction. When the pen tip 911 is moved in the rearward direction of the ultrasonic pen 91 , the rear end of the pen tip 911 comes into contact with the switch 912 and depresses the switch 912 . When the switch 912 is depressed, the ultrasonic wave is transmitted from the ultrasonic transmitter 913 . Further, the transmission start signal (the Low signal) is output from the signal output circuit 914 . The ultrasonic wave transmitted from the ultrasonic transmitter 913 may be received by the receivers 94 and 95 (refer to FIG. 1 ).
The receivers 94 and 95 will be explained with reference to FIG. 4 to FIG. 6 . Structures of the receivers 94 and 95 are the same, and an explanation of the receiver 95 will therefore be omitted, and the receiver 94 will be explained. In the explanation below, the lower left side, the upper right side, the upper left side, the lower right side, the upper side, and the lower side in FIG. 4 respectively define the front side, the rear side, the left side, the right side, the upper side, and the lower side of the receiver 94 .
As shown in FIG. 4 to FIG. 6 , the receiver 94 has a rectangular parallelepiped shape that is slightly longer in the up-down direction. An opening 941 is provided in the center of the lower edge of the front surface of the receiver 94 . The opening 941 has an elliptic shape that is long in the left-right direction. A wall 942 around the opening 941 is a taper-shaped surface (an inclined surface) that becomes narrower from the outer side toward the inner side of the front surface of the receiver 94 . A microphone 944 , which is mounted on an electric substrate 943 , is provided, inside the receiver 94 , behind the opening 941 . A connector 945 is mounted on the upper end of the rear surface of the electric substrate 943 . The receiver 94 may be electrically connected to the sewing machine 1 by the connector 945 being connected to a connector (not shown in the drawings) provided on the sewing machine 1 . An orientation of the receiver 94 is determined by a direction of the opening 941 in relation to the microphone 944 .
In a case where the ultrasonic wave is transmitted from the ultrasonic transmitter 913 , the ultrasonic wave may be received by the microphone 944 of the receiver 94 . The receiver 94 may output the received ultrasonic wave, as an electrical signal, to the sewing machine 1 via the connector 945 . The sewing machine 1 may detect the ultrasonic wave in this way.
An electrical configuration of the sewing machine 1 and the ultrasonic pen 91 will be explained with reference to FIG. 7 . As shown in FIG. 7 , the control portion 60 of the sewing machine 1 includes the CPU 61 , a ROM 62 , a RAM 63 , an EEPROM 64 , and an input/output interface 65 , which are mutually connected via a bus 67 . The ROM 62 stores programs and data etc. that are used by the CPU 61 to execute processing. The EEPROM 64 stores data of a plurality of types of sewing patterns that are used for the sewing machine 1 to perform sewing.
The switch cluster 21 , the touch panel 26 , a timer 27 , the potentiometer 51 , and drive circuits 71 to 77 are electrically connected to the input/output interface 65 . The timer 27 may measure time. The drive circuit 71 may drive the feed adjustment motor 83 . The drive circuit 72 may drive the sewing machine motor 79 . The drive circuit 73 may drive the presser foot lifting motor 56 . The drive circuit 74 may drive the needle bar swinging motor 80 . The drive circuit 75 may drive the liquid crystal display 15 . The drive circuits 76 and 77 may drive the receiver 94 and the receiver 95 , respectively. The drive circuits 76 and 77 include amplifier circuits that amplify the electrical signals output from the receivers 94 and 95 and transmit the amplified electrical signals to the CPU 61 .
As described above, the switch 912 , the ultrasonic transmitter 913 , and the signal output circuit 914 are mounted on the electric substrate inside the ultrasonic pen 91 . The switch 912 is connected to the ultrasonic transmitter 913 and to the signal output circuit 914 . The signal output circuit 914 is connected to the CPU 61 via the input/output interface 65 . The signal output circuit 914 may output the transmission start signal to the CPU 61 .
A calculation method used to calculate the position of the ultrasonic wave transmission source on the work cloth 100 , namely the position specified by using the ultrasonic pen 91 , will be explained. In the following explanation, the left-right direction of the sewing machine 1 is the X direction (X coordinates), the front-rear direction of the sewing machine 1 is the Y direction (Y coordinates), and the up-down direction of the sewing machine 1 is the Z direction (Z coordinates). As described above, the sewing machine 1 can perform sewing at the position on the work cloth 100 specified by using the ultrasonic pen 91 . Here, if the thickness of the work cloth 100 is not taken into account when identifying the transmission source of the ultrasonic wave, an error may occur in the position (X coordinate, Y coordinate) of the identified transmission source. In particular, the greater the thickness, the greater error may occur in the position (X coordinate, Y coordinate) of the transmission source of the ultrasonic wave. For that reason, there is a possibility that the sewing is performed in a position that is separated from the specified position by the amount of the error. Therefore, in the present embodiment, the thickness is taken into account and the position (X coordinate, Y coordinate) of the transmission source of the ultrasonic wave is calculated, thus inhibiting occurrence of an error. Hereinafter, a calculation method used to calculate the position (X coordinate, Y coordinate) of the transmission source of the ultrasonic wave will be explained.
In the following explanation, “1” in the X coordinate, the Y coordinate, and the Z coordinate corresponds to a distance of “1 mm” from an origin. As shown in FIG. 8 , coordinates of a center position of a needle hole (not shown in the drawings) in the needle plate 22 that is penetrated by the sewing needle 29 are assumed to be the origin (0, 0, 0). Coordinates B indicating the position of the receiver 94 are denoted by (Xb, Yb, Zb), and coordinates C indicating the position of the receiver 95 are denoted by (Xc, Yc, Zc). Coordinates E of the position specified on the work cloth 100 using the ultrasonic pen 91 are denoted by (Xe, Ye, Ze). Hereinafter, the coordinates E are referred to as “specified coordinates E.” A distance between the specified coordinates E and the coordinates B is referred to as a “distance EB.” A distance between the specified coordinates E and the coordinates C is referred to as a “distance EC.”
The Z coordinate of the upper surface of the needle plate 22 is zero. Thus, the Z coordinates of the receivers 94 and 95 indicate, respectively, distances between the needle plate 22 and the receivers 94 and 95 in an orthogonal direction (the up-down direction) that is orthogonal to the upper surface of the needle plate 22 . As described above, the upper surface of the bed 11 and the upper surface of the needle plate 22 are substantially the same height, and therefore the Z coordinate of the bed 11 may be deemed to be zero. Then, the Z coordinates of the receivers 94 and 95 may indicate, respectively, distances between the upper surface of the bed 11 and the receivers 94 and 95 in an orthogonal direction (the up-down direction) that is orthogonal to the upper surface of the bed 11 . The coordinates B (Xb, Yb, Zb) and the coordinates C (Xc, Yc, are stored in advance in the ROM 62 .
In the case of the above-described conditions, a relationship of the following Formulas (1) and (2) is obtained.
( Xb−Xe ) 2 +( Yb−Ye ) 2 +( Zb−Ze ) 2 =( EB ) 2 Formula (1):
( Xc−Xe ) 2 +( Yc−Ye ) 2 +( Zc−Ze ) 2 =( EC ) 2 Formula (2):
Formulas (1) and (2) are the same as equations to calculate a spherical surface. In the present embodiment, the receivers 94 and 95 provided at the coordinates B and the coordinates C may receive the ultrasonic wave transmitted from the ultrasonic pen 91 (the ultrasonic wave transmitted from the specified coordinates E). Here, a speed at which the ultrasonic wave travels is assumed to be a sonic velocity V. A time period required from when the ultrasonic wave is transmitted from the ultrasonic pen 91 at the specified coordinates E to when the ultrasonic wave reaches the receiver 94 (to be detected by the receiver 94 ) is a propagation time Tb. A time period required from when the ultrasonic wave is transmitted from the ultrasonic pen 91 at the specified coordinates E to when the ultrasonic wave reaches the receiver 95 (to be detected by the receiver 95 ) is a propagation time Tc. In this case, the distance can be expressed as (speed×time). Thus, the distance EB between the specified coordinates E and the receiver 94 , and the distance EC between the specified coordinates E and the receiver 95 in Formulas (1) and (2) can be expressed by the following Formulas (3) and (4).
EB=V×Tb Formula (3):
EC=V×Tc Formula (4):
Formulas (3) and (4) are substituted into Formulas (1) and (2), so that the following Formulas (5) and (6) can be obtained.
( Xb−Xe ) 2 +( Yb−Ye ) 2 +( Zb−Ze ) 2 =( V×Tb ) 2 Formula (5):
( Xc−Xe ) 2 +( Yc−Ye ) 2 +( Zc−Ze ) 2 =( V×Tc ) 2 Formula (6):
In Formulas (5) and (6), the coordinates B (Xb, Yb, Zb), the coordinates C (Xc, Yc, Zc), and the sonic velocity V are known values and are stored in the ROM 62 . The propagation time Tb and the propagation time Tc can be calculated from a difference between a transmission timing T 1 and a detection timing T 2 of the ultrasonic wave, which will be explained below. The specified coordinates E may be coordinates of the position on the work cloth 100 specified using the ultrasonic pen 91 . Thus, Ze of the specified coordinates E (Xe, Ye, Ze) may indicate the thickness of the work cloth 100 . For that reason, Xe and Ye can be calculated by solving the simultaneous equations represented by the above-described Formulas (5) and (6). Here, taking orientations of the receivers 94 and 95 into account, the X coordinate “Xe” and the Y coordinate “Ye” of the specified coordinates E specified on the work cloth 100 using the ultrasonic pen 91 can be determined. The above-described Formulas (5) and (6) are stored in the ROM 62 .
In the following explanation, in Formulas (5) and (6), distances in the up-down direction from the upper surface of the work cloth 100 to the receivers 94 and 95 , namely the distances (Zb−Ze) and (Zc−Ze), are referred to as “first distance values.” Distances from the transmission source of the ultrasonic wave (namely, the specified coordinates E) to the receivers 94 and 95 , namely the distances (V×Tb) and (V×Tc), are referred to as “second distance values.”
First main processing will be explained with reference to a flowchart in FIG. 9 . The first main processing is performed by the CPU 61 of the sewing machine 1 in accordance with the program stored in the ROM 62 . The first main processing may be started, for example, when an instruction is input via a panel operation to select the sewing pattern and to perform the sewing, in a state in which the presser foot 30 is pressing the work cloth 100 . In the following explanation, as a specific example, the coordinates B of the receiver 94 are denoted by (Xb, Yb, Zb) and the coordinates C of the receiver 95 are denoted by (Xc, Yc, Zc) (refer to FIG. 8 ).
As shown in FIG. 9 , in the first main processing, first, the voltage corresponding to the resistance value of the potentiometer 51 is detected, and the thickness Ze of the work cloth 100 is detected using the method described above (step S 11 ). The thickness Ze indicates a height from the needle plate 22 (the bed 11 ). Next, the first distance values are calculated (step S 12 ). Specifically, the Z coordinates (Zb, Zc) of the receivers 94 and 95 stored in the ROM 62 are read out. Using the read out Z coordinates and the thickness Ze detected at step S 11 , the first distance value (Zb−Ze) for the receiver 94 and the first distance value (Zc−Ze) for the receiver 95 are calculated. At step S 22 to be described below, the first distance values (Zb−Ze) and (Zc−Ze) calculated at step S 12 are substituted into the above-described Formulas (5) and (6).
Next, a determination is made as to whether the transmission start signal from the ultrasonic pen 91 has been detected (step S 13 ). If the transmission start signal has not been detected (NO at step S 13 ), the processing returns to step S 13 . When an arbitrary position on the work cloth 100 is specified using the ultrasonic pen 91 , the transmission start signal (Low signal) is output from the ultrasonic pen 91 (the transmission timing is notified), and the transmission start signal may be detected by the CPU 61 . The ultrasonic wave is transmitted from the ultrasonic pen 91 simultaneously with the output of the transmission start signal. The velocity of the ultrasonic wave (namely, the sonic velocity) is slower than the transmission speed of the transmission start signal and thus the ultrasonic wave reaches the receivers 94 and 95 at a later timing than the transmission start signal.
If the transmission start signal has been detected (YES at step S 13 ), the timer 27 (refer to FIG. 7 ) is referred to. A time at which the transmission start signal has been detected is identified as the transmission timing T 1 at which the ultrasonic wave has been transmitted (step S 14 ). The identified transmission timing T 1 is stored in the RAM 63 . Next, a determination is made as to whether at least one of the receiver 94 and the receiver 95 has detected the ultrasonic wave transmitted from the ultrasonic pen 91 (step S 15 ). If the ultrasonic wave has not been detected (NO at step S 15 ), a determination is made as to whether a predetermined time period (one second, for example) has elapsed (step S 16 ). If the predetermined time period has not elapsed (NO at step S 16 ), the processing returns to step S 15 . Namely, the sewing machine 1 stands by for 1 second until the ultrasonic wave is detected.
For example, in a case where the ultrasonic wave does not reach the receivers 94 and 95 due to being blocked by an object or the like, the predetermined time period elapses. If the predetermined time period elapses (YES at step S 16 ), an error message indicating that the ultrasonic wave has not been detected is displayed on the liquid crystal display 15 (step S 17 ). Through the above-described processing, the sewing machine 1 can notify the user that the error has occurred. Next, the processing returns to step S 13 .
If the ultrasonic wave has been detected within the predetermined time period (YES at step S 15 ), the timer 27 is referred to. A time at which the ultrasonic wave has been detected is identified as a detection timing T 2 at which the ultrasonic wave has been detected (step S 18 ). The identified detection timing T 2 is stored in the RAM 63 . At step S 18 , the detection timing T 2 is identified for each of the receivers 94 and 95 that have detected the ultrasonic wave. Next, a determination is made as to whether the ultrasonic wave has been detected by both the receivers 94 and 95 (step S 19 ). If either of the receivers 94 and 95 has not detected the ultrasonic wave, it is determined that the ultrasonic wave has not been detected by both the receiver 94 and the receiver 95 (NO at step S 19 ), and the processing returns to step S 15 . In the following explanation, the detection timing T 2 of the receiver 94 is referred to as a detection timing T 2 b and the detection timing T 2 of the receiver 95 is referred to as a detection timing T 2 c.
If both the receivers 94 and 95 have detected the ultrasonic wave (YES at step S 19 ), the propagation times Tb and Tc required for the ultrasonic wave to reach the receivers 94 and 95 after the ultrasonic wave was transmitted are calculated (step S 20 ). The propagation times Tb and Tc are each calculated by subtracting the transmission timing T 1 from the detection timing T 2 . In other words, the propagation time Tb with respect to the receiver 94 is (T 2 b −T 1 ). The propagation time Tc with respect to the receiver 95 is (T 2 c −T 1 ).
Next, the second distance values between the transmission source of the ultrasonic wave (namely, the specified coordinates E) and the receivers 94 and 95 are calculated (step S 21 ). Specifically, the propagation times Tb and Tc calculated at step S 20 , and the sonic velocity V stored in the ROM 62 are used to calculate the second distance value (V×Tb) with respect to the receiver 94 and the second distance value (V×Tc) with respect to the receiver 95 .
Next, a position of the transmission source of the ultrasonic wave on the work cloth 100 , namely, the specified coordinates E (Xe, Ye, Ze) specified by the ultrasonic pen 91 are identified (step S 22 ). Specifically, (Xe, Ye) are calculated by solving the simultaneous equations represented by the above-described Formulas (5) and (6). In this way, the specified coordinates E (Xe, Ye, Ze) are identified.
Here, the first distance values (Zb−Ze) and (Zc−Ze) in Formulas (5) and (6) have been calculated at step S 12 . The second distance values (V×Tb) and (V×Tc) have been calculated at step S 21 . Xb, Yb, Xc and Yc are stored in the ROM 62 . Thus, Xe and Ye can be calculated by solving the simultaneous equations represented by the above-described Formulas (5) and (6). The specified coordinates E (Xe, Ye, Ze) can be identified in this manner.
Next, the identified coordinates (Xe, Ye, Ze) (namely, the position of the transmission source of the ultrasonic wave) is displayed on the liquid crystal display 15 (step S 23 ). Through the above-described processing, the specified coordinates E of the position specified by the ultrasonic pen 91 can be notified to the user. An error message may be displayed on the liquid crystal display 15 in a case where the work cloth 100 cannot be moved such that the position, on the work cloth 100 , indicated by the specified coordinates E is moved to the needle drop point (the center of the needle hole in the needle plate 22 ).
Next, a determination is made as to whether the sewing start/stop switch included in the switch cluster 21 has been pressed (step S 24 ). If the sewing start/stop switch has not been pressed (NO at step S 24 ), the processing at step S 24 is repeated. If the sewing start/stop switch has been pressed (YES at step S 24 ), the feed dog 34 is driven and the work cloth 100 is fed such that the X coordinate “Xe” and the Y coordinate “Ye” of the specified coordinates E specified at step S 22 are positioned at the needle drop point (step S 25 ). The specified coordinates E indicate the position, on the work cloth 100 , of the transmission source of the ultrasonic wave. Next, sewing is performed on the work cloth 100 (step S 26 ). By the processing at steps S 25 and S 26 , the sewing is started from the position (the specified coordinates E) specified by the ultrasonic pen 91 . When the sewing is completed, the first main processing ends.
In the present embodiment, when the user specifies the position on the work cloth 100 using the ultrasonic pen 91 , the position of the transmission source of the ultrasonic wave on the work cloth 100 (the position specified by the user) may be identified based on the ultrasonic wave detected by the receivers 94 and 95 and on the thickness Ze of the work cloth 100 detected by the potentiometer 51 (step S 22 ). In other words, the user may easily set the position on the work cloth 100 on which the sewing is to be performed, by using the ultrasonic pen 91 . Further, based on the identified position of the transmission source of the ultrasonic wave, the sewing may be performed at the position, on the work cloth 100 , specified by using the ultrasonic pen 91 (steps S 25 and S 26 ). As a result, it is possible to perform the sewing at the position on the work cloth 100 set by the user, and user convenience may be thus improved.
As described above, in a case where the thickness Ze of the work cloth 100 is not taken into account when identifying the transmission source of the ultrasonic wave, an error may occur with respect to the identified position (X coordinate, Y coordinate) of the transmission source on the work cloth 100 . The greater the thickness Ze is, the greater error may occur with respect to the position (X coordinate, Y coordinate) of the transmission source of the ultrasonic wave. In the present embodiment, the thickness Ze of the work cloth 100 is detected and the position (Xe, Ye) of the transmission source of the ultrasonic wave is identified using the detected thickness Ze (step S 22 ). As a result, even if the thickness Ze of the work cloth 100 changes, it is possible to accurately identify the position of the transmission source. In other words, even when the work cloth having the different thickness Ze is used, it is possible to accurately identify the position of the transmission source. The position of the transmission source can be highly accurately identified, and thus the sewing can be accurately performed at the position (the specified coordinates E) specified by the ultrasonic pen 91 .
In the present embodiment, the second distance values can be calculated using the transmission timing T 1 and the detection timing T 2 . Then, the position of the transmission source of the ultrasonic wave on the work cloth 100 can be identified using the first distance values, the second distance values, the coordinates B (Xb, Yb, Zb) of the receiver 94 , and the coordinates C (Xc, Ye, Ze) of the receiver 95 . For that reason, it is possible to correct an error in the position of the transmission source resulting from an influence of the thickness Ze. Thus, the position of the transmission source can be identified with a high degree of accuracy. As a result, it is possible to accurately perform the sewing at the position specified by the ultrasonic pen 91 .
When the user uses the ultrasonic pen 91 to specify the position on the work cloth 100 , the ultrasonic wave is transmitted from the ultrasonic transmitter 913 . In addition, the transmission timing is notified by the transmission start signal being output from the signal output circuit 914 . As a result, in the processing at step S 22 , it is possible to identify the position of the transmission source of the ultrasonic wave on the work cloth 100 . The user can use the ultrasonic pen 91 to easily specify the position on the work cloth 100 . Thus, user convenience may be improved.
A second embodiment will be explained. In the first embodiment, the ultrasonic pen 91 may transmit the ultrasonic wave and the transmission start signal. In the second embodiment, an ultrasonic pen 92 (refer to FIG. 10 ) may transmit the ultrasonic wave but does not transmit the transmission start signal.
In the second embodiment, as shown in FIG. 10 , in addition to the receivers 94 and 95 of the first embodiment, the sewing machine 1 is provided with a receiver 96 that has the same structure as the receivers 94 and 95 . Specifically, the three receivers 94 , 95 and 96 are provided on the sewing machine 1 . The positions of the receivers 94 and 95 are the same as those of the first embodiment. The receiver 96 is provided on the left surface of the pillar 12 , in a posture in which the opening 941 faces to the left.
The ultrasonic pen 92 of the second embodiment is not provided with a cable that connects to the sewing machine 1 . The ultrasonic pen 92 accommodates a battery (not shown in the drawings). The ultrasonic pen 92 operates by electric power of the battery. Thus, in a case where the ultrasonic pen 92 is used, the cable does not cause interference. The ultrasonic pen 92 includes the ultrasonic transmitter 913 but does not include a signal output circuit.
An electrical configuration of the sewing machine 1 and the ultrasonic pen 92 of the second embodiment will be explained with reference to FIG. 11 . As shown in FIG. 11 , in comparison to the sewing machine 1 of the first embodiment (refer to FIG. 7 ), the sewing machine 1 of the second embodiment further includes the receiver 96 and a drive circuit 81 . The drive circuit 81 is connected to the input/output interface 65 . The drive circuit 81 may drive the receiver 96 . In comparison to the case of the first embodiment (refer to FIG. 7 ), the ultrasonic pen 92 does not include the signal output circuit 914 . The ultrasonic pen 92 is not electrically connected to the sewing machine 1 .
A calculation method used to calculate the position of the transmission source of the ultrasonic wave in the second embodiment, namely, a calculation method used to calculate the position specified by using the ultrasonic pen 92 , will be explained with reference to FIG. 12 . In the following explanation, as shown in FIG. 12 , coordinates D indicating the position of the receiver 96 are denoted by (Xd, Yd, Zd). A distance between the specified coordinates E and the coordinates D of the receiver 96 is referred to as a “distance ED.” Other conditions (the origin, the coordinates B, the coordinates C, the specified coordinates E, and the like) are the same as those of the first embodiment (refer to FIG. 8 ). In this case, relationships of the following Formulas (7) to (9) are obtained.
( Xb−Xe ) 2 +( Yb−Ye ) 2 +( Zb−Ze ) 2 =( EB ) 2 Formula (7):
( Xe−Xe ) 2 +( Yc−Ye ) 2 +( Zc−Ze ) 2 =( EC ) 2 Formula (8):
( Xd−Xe ) 2 +( Yd−Ye ) 2 +( Zd−Ze ) 2 =( ED ) 2 Formula (9):
Formulas (7) to (9) are each the same as the equation to calculate a spherical surface. In the present embodiment, the ultrasonic wave transmitted from the ultrasonic pen 92 (the ultrasonic wave transmitted from the specified coordinates E) can be received by the receivers 94 , 95 , and 96 , which are provided at the coordinates B, the coordinates C, and the coordinates D. A time period required from when the ultrasonic wave is transmitted from the ultrasonic pen 92 at the specified coordinates E to when the ultrasonic wave reaches the receiver 96 (to be detected by the receiver 96 ) is a propagation time Td. The propagation times Tb and Tc are the same as in the first embodiment. The distances can be expressed as (speed×time). Thus, the distances EB, EC and ED between the specified coordinates E and the respective receivers 94 , 95 and 96 can be expressed by the following Formulas (10), (11), and (12).
EB=V×Tb Formula (10):
EC=V×Tc Formula (11):
ED=V×Td Formula (12):
Further, Formulas (11) and (12) can be transformed into the following Formulas (13) and (14).
EC=V×Tc=V ×( Tc−Tb )+ V×Tb Formula (13):
ED=V×Td=V ×( Td−Tb )+ V×Tb Formula (14):
The ultrasonic pen 92 of the second embodiment does not transmit the transmission start signal. Thus, in contrast to the first embodiment, the CPU 61 of the sewing machine 1 does not acquire the transmission timing T 1 . The CPU 61 may receive the detection timings T 2 b , T 2 c , and T 2 d at which the respective receivers 94 , 95 , and 96 have been detected the ultrasonic wave. T 2 d is the detection timing of the receiver 96 . The CPU 61 does not acquire the transmission timing T 1 , and thus does not calculate the propagation times Tb, Tc, and Td for the ultrasonic wave to reach the respective receivers 94 , 95 , and 96 . Therefore, the propagation times Tb, Tc, and Td are unknown values. However, the propagation time difference (Tc−Tb) in Formula corresponds to a difference between the detection timing T 2 c and the detection timing T 2 b . The propagation time difference (Td−Tb) in Formula (14) corresponds to a difference between the detection timing T 2 d and the detection timing T 2 b . Thus, the above-described Formulas (13) and (14) can be transformed into the following Formulas (15) and (16).
EC=V ×( T 2 c−T 2 b )+ V×Tb Formula (15):
ED=V ×( T 2 d−T 2 b )+ V×Tb Formula (16):
The above-described Formulas (10) to (16) are substituted into the Formulas (7) to (9) and the following Formulas (17) to (19) are obtained.
( Xb−Xe ) 2 +( Yb−Ye ) 2 +( Zb−Ze ) 2 =( V×Tb ) 2 Formula (17):
( Xc−Xe ) 2 +( Yc−Ye ) 2 +( Zc−Ze ) 2 ={V ×( T 2 c−T 2 b )+ V×Tb} 2 Formula (18):
( Xd−Xe ) 2 +( Yd−Ye ) 2 +( Zd−Ze ) 2 ={V ×( T 2 d−T 2 b )+ V×Tb} 2 Formula (19):
In the above-described Formulas (17) to (19), the coordinates B (Xb, Yb, Zb) of the receiver 94 , the coordinates C (Xc, Yc, Zc) of the receiver 95 , and the coordinates D (Xd, Yd, Zd) of the receiver 96 are stored in advance in the ROM 62 . The sonic velocity V is stored in the ROM 62 . The detection timings T 2 b , T 2 c , and T 2 d can be acquired by processing at step S 181 (refer to FIG. 13 ), which will be described below. The specified coordinates E are the coordinates on the work cloth 100 that are specified using the ultrasonic pen 92 . Thus, Ze of the specified coordinates E (Xe, Ye, Ze) indicates the thickness of the work cloth 100 . As a result, the unknown values in the Formulas (17) to (19) are Xe, Ye, and Tb. Xe, Ye, and Tb can be calculated by solving the simultaneous equations represented by the above-described Formulas (17) to (19). In other words, the X coordinate “Xe” and the Y coordinate “Ye” of the specified coordinates E specified on the work cloth 100 using the ultrasonic pen 92 can be calculated. The above-described Formulas (17) to (19) are stored in the ROM 62 .
In the following explanation, of the Formulas (17) to (19), distances in the up-down direction from the upper surface of the work cloth 100 to the receivers 94 , 95 , and 96 , namely the distances (Zb−Ze), (Zc−Ze), and (Zd−Ze), are referred to as the “first distance values.” Distances from the transmission source of the ultrasonic wave (namely, the specified coordinates E) to the receivers 94 , 95 , and 96 , namely the distances (V×Tb), {V×(T 2 c −T 2 b )+V×Tb}, and {V×(T 2 d −T 2 b )+V×Tb}, are referred to as the “third distance values.”
Second main processing will be explained with reference to a flowchart shown in FIG. 13 . In the second main processing, the same reference numerals are assigned to processing that is the same as that of the first main processing (refer to FIG. 9 ) and a detailed explanation of that processing is omitted. In the following explanation, the coordinates B of the receiver 94 are denoted by (Xb, Yb, Zb), the coordinates C of the receiver 95 are denoted by (Xc, Yc, Zc) and the coordinates D of the receiver 96 are denoted by (Xd, Yd, Zd) (refer to FIG. 12 ).
As shown in FIG. 13 , in the second main processing, first, similarly to the first main processing, the thickness Ze is detected (step S 11 ). Next, the first distance values are calculated (step S 121 ). Specifically, the Z coordinates (Zb, Ze, Zd) of the receivers 94 , 95 , and 96 that are stored in the ROM 62 are read out. The read out Z coordinates and the thickness Ze detected at step S 11 are used to calculate the first distance value (Zb−Ze) for the receiver 94 , the first distance value (Zc−Ze) for the receiver 95 and the first distance value (Zd−Ze) for the receiver 96 . At step S 221 , which will be described below, the first distance values (Zb−Ze), (Zc−Ze), and (Zd−Ze) calculated at step S 121 are substituted into the above-described Formulas (17), (18) and (19).
Next, a determination is made as to whether the ultrasonic wave transmitted from the ultrasonic pen 92 has been detected by at least one of the receivers 94 , 95 , and 96 (step S 151 ). If the ultrasonic wave has not been detected (NO at step S 151 ), the processing at step S 151 is repeated. Namely, the sewing machine 1 stands by until the specified coordinates E are specified using the ultrasonic pen 92 and the ultrasonic wave transmitted from the ultrasonic pen 92 is detected.
If the ultrasonic wave has been detected (YES at step S 151 ), the timer 27 is referred to. The time at which the ultrasonic wave has been detected is identified (acquired) as the detection timing T 2 at which the ultrasonic wave is detected (step S 181 ). The identified detection timing T 2 is stored in the RAM 63 . At step S 181 , the detection timing T 2 is identified for each of the receivers 94 , 95 , and 96 that have detected the ultrasonic wave. Next, a determination is made as to whether or not the ultrasonic wave has been detected by all of the receivers 94 , 95 , and 96 (step S 191 ). In a case where there is one or more of the receivers 94 , 95 and 96 that have not detected the ultrasonic wave, it is determined that the ultrasonic wave has not been detected by at least one of the receivers 94 to 96 (NO at step S 191 ) and the processing returns to step S 151 . In the following explanation, the detection timings T 2 for the receivers 94 , 95 , and 96 are referred to as detection timings T 2 b , T 2 c , and T 2 d , respectively.
In a case where the ultrasonic wave has been detected by all of the receivers 94 , 95 , and 96 (YES at step S 191 ), differences between the detection timings T 2 , namely, (T 2 c −T 2 b ) and (T 2 d −T 2 b ), are calculated (step S 31 ).
Next, third distance values between the transmission source of the ultrasonic wave (namely, the specified coordinates E) and the receivers 94 , 95 , and 96 are calculated (step S 211 ). Specifically, the detection timing T 2 b identified at step S 181 , (T 2 c −T 2 b ) and (T 2 d −T 2 b ) calculated at step S 31 , and the sonic velocity V stored in the ROM 62 are used to calculate the third distance value (V×Tb) with respect to the receiver 94 , the third distance value {V×(T 2 c −T 2 b )+V×Tb} with respect to the receiver 95 , and the third distance value {V×(T 2 d −T 2 b )+V×Tb} with respect to the receiver 96 . Here, the value of the propagation time Tb is unknown, and the propagation time Tb remains as the unknown value.
Next, the position of the ultrasonic wave transmission source on the work cloth 100 , namely, the specified coordinates E (Xe, Ye, Ze) specified using the ultrasonic pen 92 are identified (step S 221 ). Specifically, (Xe, Ye) and Tb are calculated by solving the simultaneous equations represented by the above-described Formulas (17) to (19). Thus, the specified coordinates E (Xe, Ye, Ze) are identified.
Here, in the Formulas (17) to (19), the first distance values (Zb−Ze), (Zc−Ze), and (Zd−Ze) have been calculated at step S 121 . The third distance values (V×Tb), {V×(T 2 c −T 2 b )+V×Tb}, and {V×(T 2 d −T 2 b )+V×Tb} have been calculated at step S 211 . However, the propagation time Tb is unknown. The sonic velocity V is stored in the ROM 62 . Xb, Yb, Xc, Yc, Xd, and Yd are stored in the ROM 62 . Thus, the unknown values are Xe, Ye, and Tb, only. As a result, Xe, Ye and Tb can be calculated by solving the simultaneous equations represented by the above-described Formulas (17) to (19). In this way, the specified coordinates E (Xe, Ye, Ze) are identified. Next, the processing from steps S 23 to S 26 is performed in a similar manner to the first embodiment.
In the present embodiment, similarly to the first embodiment, the user can easily set a position on the work cloth 100 on which the sewing is to be performed using the ultrasonic pen 92 . Further, the sewing can be performed on the work cloth 100 at the position set by the user. As a result, user convenience may be improved. In addition, even if the thickness Ze of the work cloth 100 is changed, the position of the transmission source of the ultrasonic wave (the position specified by the user) can be accurately identified. In other words, even if the work cloth 100 having a different thickness Ze is used, it is possible to accurately identify the position of the transmission source. Therefore, the sewing machine 1 can identify the position of the transmission source with a high degree of accuracy. As a result, the sewing can be accurately performed at the position (the specified coordinates E) specified using the ultrasonic pen 92 .
In the second embodiment, the third distance values can be calculated from the detection timings T 2 at which the ultrasonic wave has been detected by the three receivers 94 , 95 , and 96 . Then, it is possible to identify the position of the transmission source of the ultrasonic wave on the work cloth 100 using the first distance values, the third distance values, the coordinates B (Xb, Yb, Zb) of the receiver 94 , the coordinates C (Xc, Yc, Zc) of the receiver 95 , and the coordinates D (Xd, Yd, Zd) of the receiver 96 . As a result, an error in the position of the transmission source resulting from the influence of the thickness Ze can be corrected. Thus, the position of the transmission source can be identified with a high degree of accuracy. Accordingly, the sewing can be accurately performed at the position specified using the ultrasonic pen 92 .
Strictly speaking, the identified position is not a position on the work cloth 100 that is touched and pressed by the pen tip 911 , but is a position of the ultrasonic transmitter 913 provided in the ultrasonic pen 91 (or the ultrasonic pen 92 ). However, the pen tip 911 and the ultrasonic transmitter 913 are arranged such that the pen tip 911 and the ultrasonic transmitter 913 are extremely close together. As a result, the position of the ultrasonic transmitter 913 may be regarded as being the position on the work cloth 100 that is touched and pressed by the pen tip 911 .
The present disclosure is not limited to the above-described embodiments and various modifications may be made. For example, in the above-described embodiments, the potentiometer 51 is used in order to detect the thickness Ze, but the present disclosure is not limited to this example. For example, light or an ultrasonic wave may be emitted toward the work cloth 100 and the thickness Ze may be detected by detecting the light or the ultrasonic wave reflected by the work cloth 100 . The sewing machine 1 may be provided with a camera. An image of the work cloth 100 may be captured by the camera and the thickness Ze may be detected based on the captured image.
In the first embodiment, the first distance values are calculated at step S 12 , and the second distance values are calculated at step S 21 . Then, at step S 22 , the first distance values and the second distance values are substituted into Formulas (5) and (6), and (Xe, Ye) in the specified coordinates E are calculated. (Xe, Ye) in the specified coordinates E may be calculated using a different method. For example, the processing at steps S 12 and S 21 need not necessarily be performed. The values Xb, Yb, Zb, Ze, V, Tb, Xc, Yc, Zc, and Tc may be directly substituted into Formulas (5) and (6) at step S 22 , and (Xe, Ye) of the specified coordinates E may be thus calculated. In this case, the calculation of the first distance values (Zb−Ze) and (Zc−Ze) performed at step S 12 may be performed at step S 22 . Further, the calculation of the second distance values (V×Tb) and (V×Tc) performed at step S 21 may be performed at step S 22 .
In the second embodiment, the first distance values are calculated at step S 121 , and the values calculated at step S 31 are used to calculate the third distance values at step S 211 . At step S 221 , the first distance values and the third distance values are substituted into Formulas (17) to (19), and (Xe, Ye) in the specified coordinates E and Tb are calculated. (Xe, Ye) in the specified coordinates E and Tb may be calculated using a different method. For example, the processing at steps S 121 and S 211 need not necessarily be performed. The values Xb, Yb, Zb, Ze, V, Xc, Yc, Zc, T 2 c , T 2 b , and T 2 d may be directly substituted into Formulas (17) to (19) at step S 221 , and (Xe, Ye) of the specified coordinates E and Tb may be thus calculated. In this case, the calculation of the first distance values (Zb−Ze), (Zc−Ze), and (Zd−Ze) performed at step S 121 may be performed at step S 221 . Further, the calculation of the third distance values (V×Tb), {V×(T 2 c −T 2 b )+V×Tb}, and {V×(T 2 d −T 2 b )+V×Tb} performed at step S 211 may be performed at step S 221 .
In the first embodiment, in a case where the electrical transmission start signal (the Low signal) from the ultrasonic pen 91 is detected, and the transmission timing T 1 is acquired (steps S 13 and S 14 ). However, the transmission timing T 1 may be detected using a different method. For example, an infrared transmitter may be provided in the ultrasonic pen 91 . Then, the ultrasonic pen 91 may transmit an infrared ray at the same time as transmitting the ultrasonic wave. Further, an infrared detector that may detect the infrared ray transmitted from the ultrasonic pen 91 may be provided in the sewing machine 1 . The infrared ray travels at the speed of light. Thus, the infrared ray reaches the infrared detector at substantially the same time as the start of transmission of the ultrasonic wave. As a result, the sewing machine 1 can set the transmission timing T 1 as a time point at which the infrared detector detects the infrared ray transmitted from the ultrasonic pen 91 .
The sonic velocity V changes depending on ambient temperature. For example, a temperature sensor, such as a thermistor, may be provided in the sewing machine 1 and the temperature may be measured. Then, the sonic velocity V corresponding to the ambient temperature may be used.
At step S 25 , the work cloth 100 is fed by the feed dog 34 . However, the work cloth 100 may be moved by a different method. For example, a known embroidery unit may be attached to the sewing machine 1 . The work cloth 100 may be held by an embroidery frame, and the embroidery frame may be moved in the X direction and in the Y direction. Then, the work cloth 100 may be moved such that the position, on the work cloth 100 , indicated by the X coordinate Xe and the Y coordinate Ye of the specified coordinates E calculated at step S 22 , namely the position of the transmission source of the ultrasonic wave on the work cloth 100 , is moved to the needle drop point.
The positions of the receivers 94 to 96 in the first and second embodiments may be changed. For example, the positions of the receivers 94 to 96 on the sewing machine 1 may be changed. The receivers 94 to 96 may be disposed on the outside of the sewing machine 1 . The receivers 94 to 96 may be provided on an embroidery unit that can be attached to the sewing machine 1 .
In the first embodiment, the time at which the transmission start signal has been detected is taken as the transmission timing T 1 (step S 14 in FIG. 9 ), and the time at which the ultrasonic wave has been detected is taken as the detection timing T 2 (step S 18 in FIG. 9 ). Then the difference between T 2 and T 1 is calculated and the propagation times Tb and Tc are calculated (step S 20 in FIG. 9 ). However, the propagation times Tb and Tc may be calculated using a different method. For example, a time point at which the transmission start signal has been detected, namely, the transmission timing T 1 may be assumed to be zero seconds. Then, an elapsed time period from the time point at which the transmission start signal has been detected may be measured, and the elapsed time period until the ultrasonic wave has been detected may be taken as the detection timing T 2 . In this case, the times of the detection timing T 2 may become the propagation times Tb and Tc.
In the first embodiment, the two receivers 94 and 95 are provided. However, the number of the receivers is not limited to two. In the first embodiment, it is sufficient that at least two receivers are provided. For example, the number of the receivers may be three or more. In the second embodiment, the three receivers 94 , 95 and 96 are provided. However, the number of the receivers is not limited to three. In the second embodiment, it is sufficient that at least three receivers are provided. For example, the number of the receivers may be four or more.
In the above-described embodiments, the ultrasonic pens 91 and 92 may be used when specifying the position. The device that may transmit the ultrasonic wave need not necessarily be in the form of a pen. Another device that is capable of transmitting the ultrasonic wave may be used.
A third embodiment will be explained. The number of the receivers may be one. For example, it is assumed that the one receiver is the receiver 94 that is provided on the left lower edge of the head 14 . Then, with respect to the coordinates B indicating the position of the receiver 94 , specified coordinates indicating the specified position specified by the ultrasonic pen 91 are referred to as coordinates F. At this time, the X coordinates of the coordinates B and the coordinates F are assumed to be the same. In other words, the coordinates B are assumed to be (Xb, Yb, Zb) and the coordinates F are assumed to be (Xb, Yf, Zf). In this case, it is possible to calculate a distance FB between the coordinates F and the coordinates B, based on the propagation time required for the ultrasonic wave transmitted from the ultrasonic pen 91 that is at the coordinates F of the specified position to reach the receiver 94 . The coordinates B are known values. The Z coordinate “Zf” of the coordinates F is the thickness of the work cloth that is detected by the potentiometer 51 . Thus, with respect to the needle drop point that is the origin, the Y coordinate “Yf” of the coordinates F of the specified position can be calculated.
The apparatus and methods described above with reference to the various embodiments are merely examples. It goes without saying that they are not confined to the depicted embodiments. While various features have been described in conjunction with the examples outlined above, various alternatives, modifications, variations, and/or improvements of those features and/or examples may be possible. Accordingly, the examples, as set forth above, are intended to be illustrative. Various changes may be made without departing from the broad spirit and scope of the underlying principles. | A sewing machine includes at least one ultrasonic wave detecting portion, a thickness detecting portion, a processor, and a memory. The at least one ultrasonic wave detecting portion is configured to detect an ultrasonic wave. The thickness detecting portion is configured to detect a thickness of a work cloth. The memory configured to store computer-readable instructions that instruct the sewing machine to execute steps that includes identifying a position, on the work cloth, of a transmission source of the ultrasonic wave, based on information pertaining to the ultrasonic wave that has been detected by the at least one ultrasonic wave detecting portion and on the thickness that has been detected by the thickness detecting portion, and controlling sewing on the work cloth based on the position of the transmission source that has been identified. | 3 |
FIELD OF THE INVENTION
[0001] The invention relates generally to the fields of mechanical engineering and child safety. More particularly, the invention relates to a keyless lock for doors.
BACKGROUND
[0002] All too often parents have discovered that their small children are able to unlock and open a door to the outside of the home or a door at the top of a stairway. To avoid devastating accidents that can occur when children open doors that are not to be opened by them, parents have resorted to installing a lock on the inside surface of the door that requires the use of a key to unlock and open the door. This presents a significant inconvenience to everyone in the home who uses the door, as the key to the lock can be easily misplaced. Such a lock also presents a safety hazard in the case of fire, for example, when the lock key is not readily available and the occupants of the home, possibly panicked, are obstructed or prevented from exiting the home. A need exists for a door lock that allows adults and older children to easily operate the lock while precluding small children from doing so.
SUMMARY OF THE INVENTION
[0003] What has been developed is a keyless lock for doors that prevents young children from opening doors their parents or caretakers do not wish them to open. An exemplary keyless lock of the invention is a dead-bolt type lock having no keyed lock access side to it, but rather, a knob or handle on one or both sides of the door that when turned, locks or unlocks the door. The lock is positioned within the door at a height that is unreachable by small children (e.g., at least about 1.5 meters). The keyless lock can be used to lock hinged and sliding doors. The lock is compatible for doors for interior rooms of a home as well as for doors that provide access to the exterior of the home and therefore access for small children to leave the premises of the home without supervision. Adults and older children, however, are not locked in or out of the room or house as no key is required for operating the lock, merely the turning of a knob.
[0004] Accordingly, the invention features a door having a keyless lock. This keyless lock includes a first means for locking and unlocking the lock and a second means for locking and unlocking the lock, the first means positioned on the interior surface of the door and the second means positioned on the exterior surface of the door. The first and second means are positioned on the door at a distance from the bottom of the door of at least about 1.5 meters. The first and second means for locking and unlocking the lock can include a knob and a handle. The door can be a hinged door as well as a sliding door.
[0005] In another aspect, the invention features a kit for locking a door. This kit includes (a) a keyless lock including a first means for locking and unlocking the door and a second means for locking and unlocking the lock that when installed in the door, the first means is positioned on the interior surface of the door and the second means is positioned on the exterior surface of the door, and (b) printed instructions for installing the keyless lock in the door at a distance from the bottom of the door of at least about 1.5 meters. The first and second means for locking and unlocking the lock can include a knob and a handle. The door can be a hinged door as well as a sliding door.
[0006] Also within the invention is a method for locking a door. This method includes the steps of: (a) providing a door, (b) providing a keyless lock installed within the door, the keyless lock including a first means for locking and unlocking the lock and a second means for locking and unlocking the lock, the first means positioned on the interior surface of the door and the second means positioned on the exterior surface of the door, and (c) manipulating the first or the second means for locking and unlocking the lock. The first and second means for locking and unlocking the lock can include a knob and a handle. The door can be a hinged door as well as a sliding door.
[0007] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although systems, materials and devices similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable systems, materials, and devices are described below. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, the systems, materials, and devices are illustrative only and not intended to be limiting. Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective front view of a door having a keyless lock of the invention.
[0009] FIG. 2 is an exploded view of a first embodiment of a keyless lock.
[0010] FIG. 3 is a cross-sectional view of the embodiment of FIG. 2 , the lock being in an unlocked position.
[0011] FIG. 4 is a cross-sectional view of the embodiment of FIG. 2 , the lock being in a locked position.
[0012] FIG. 5 is an exploded view of a second embodiment of a keyless lock.
[0013] FIG. 6 is a front view of the keyless lock of FIG. 5 in a locked position.
[0014] FIG. 7 is a front view of the keyless lock of FIG. 5 in an unlocked position.
[0015] FIG. 8 is a perspective view of a sliding door having the keyless lock of FIGS. 5-7 mounted thereon.
[0016] FIG. 9 is a perspective front view of a third embodiment of a keyless lock.
[0017] FIG. 10 is a perspective view of a sliding door having the keyless lock of FIG. 9 mounted thereon.
DETAILED DESCRIPTION
[0018] In brief overview, referring to FIG. 1 , a first exemplary embodiment of a keyless door lock 20 is shown mounted in a hinged door 10 . An operator locks and unlocks the door by manipulating a means for locking and unlocking the lock. The means for locking and unlocking the lock can be any graspable implement, such as a handle or a knob. In the embodiment shown in FIGS. 1-10 , the means for locking and unlocking the lock is knob 25 , and to lock and unlock the door, one simply grasps the knob 25 and turns it in the appropriate direction. The lock 20 can include one means for locking and unlocking the lock (e.g., knob 25 ) mounted to one side of the door 10 , but preferably includes a first and a second means for unlocking the lock (e.g., two knobs 25 ), the first means mounted to the interior surface of the door and the second means mounted to the exterior surface of the door 10 . Having first and second means for unlocking and locking the lock is preferable because this allows the lock 20 to be operated from either side of the door 10 . The knob 25 can be any type of graspable implement but is preferably one that is easy to grasp and turn. The knob 25 can be made of any suitably rigid material, including metal, metal alloy, plastic, and composite materials thereof. The lock 20 is positioned at an adequate distance 22 from the ground such that a small child cannot reach the lock 20 . An adequate distance 22 from the ground is at least about 1.5 meters (e.g., 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.83, 1.9, 2.0, 2.1, 2.2 meters).
[0019] As shown in FIG. 2 , one embodiment of a keyless lock 20 includes several components for mounting and operating the lock 20 . Mounted inside the door 10 is a locking bolt housing 60 having an aperture 65 for receiving a connecting means 55 . A locking bolt 70 is disposed within the locking bolt housing 60 when the lock 20 is in a locked position but moves at least partially out of the locking bolt housing 60 when the lock 20 is in a locked position. The locking bolt 70 is moved in and out of the locking bolt housing 60 via a connecting means 55 and a knob 25 . The locking bolt 70 and knob 25 are operably connected by the connecting means 55 . In this embodiment, the connecting means 55 is shown as a ribbed connecting rod 55 . Any suitable device or component for operably connecting the knob 25 to the locking bolt 70 , however, can be used. The connecting rod 55 has a first end that is attached to the knob 25 and a second end that protrudes through the aperture 65 in the locking bolt housing 60 . In the embodiment shown in FIG. 2 , the knob 25 is attached to the first end of the connecting rod 55 by screws 35 that are screwed into screw holes 30 of the knob 25 . A decorative plate 50 is preferably installed between the connecting rod 55 and the knob 25 in order to conceal any hole made in the door 10 by the installation of the connecting rod 55 . The decorative plate 50 has a central aperture 40 through which the first end of the connecting rod 55 is disposed so that it can be attached to the knob 25 . The decorative plate 50 can be attached to the door 10 by any suitable means but in the embodiment shown in FIG. 2 , the plate 50 is attached to the door 10 via two screw holes 45 and screws that are driven therethrough.
[0020] The locking bolt 70 shown in FIG. 2 has a cavity at one end which features a series of teeth 75 for engaging the ribbed connecting rod 55 . The locking bolt 70 also includes a chamber housing a spring 73 that is positioned mostly interior to the chamber when the locking bolt 70 is positioned within the locking bolt housing 60 but that is urged out of the chamber when the locking bolt 70 is moved from the locking bolt housing 60 . When the locking bolt 70 is disposed within the locking bolt housing 60 , the spring 73 is positioned slightly out of the chamber and contacting the interior wall of the locking bolt housing 60 such that the spring 73 seats the locking bolt 70 firmly within the locking bolt housing 60 .
[0021] When the locking bolt 70 is moved from inside the locking bolt housing 60 it moves towards the portion of the door frame 15 (or door jamb or wall) that is disposed opposite to the keyless lock 20 . A mounting plate 85 having a central bore 80 therein is rigidly mounted to this portion of the door frame 15 (or door jamb or wall) for receiving the locking bolt 70 . The mounting plate 85 is rigidly mounted to the door frame 15 (or doorjamb or wall) via any suitable mounting means (e.g., screw holes 90 and screws driven therethrough).
[0022] The mechanism by which the keyless lock 20 of FIGS. 1 and 2 operates is illustrated in the cross-sectional views of FIGS. 3 and 4 . FIG. 3 illustrates a keyless lock 20 in an unlocked position in which the locking bolt 70 is disposed entirely within the locking bolt housing 60 . The second end of the connecting rod 55 is shown positioned within the locking bolt 70 cavity having a series of teeth 75 . The ribs of the ribbed connecting rod 55 mate with the spaces between the teeth 75 , thereby forming a gear in which the movement of the locking bolt 70 is caused by rotating the ribbed connecting rod 55 . The connecting rod 55 is rotated via manipulation of the knob 25 , i.e., turning the knob from a resting position. When the connecting rod 55 is rotated in the direction of the arrow in FIG. 3 , the ribs of the connecting rod 55 grip the teeth 75 of the locking bolt 70 and the connecting rod 55 moves in the direction of the arrow while it urges the locking bolt 70 out of the locking bolt housing 60 . As the locking bolt 70 is urged from the locking bolt housing 60 , the locking bolt 70 is urged into the central bore 80 of the mounting plate 85 ( FIG. 4 ), thereby locking the door. To unlock the door, the connecting rod 55 is rotated in the opposite direction and the movement of the locking bolt 70 is reversed, disposing the locking bolt 70 within the locking bolt housing 60 . In addition to the dead bolt-type lock described above, any bolt mechanism (e.g., spring-loaded or other mechanism) can be used in a keyless lock of the invention. In addition to the mounting plate for receiving the locking bolt described above, a keyless lock of the invention can be mounted to a door, door frame, or door jamb by any suitable mounting means.
[0023] Another exemplary embodiment of a keyless lock 20 is shown in FIG. 5 . The keyless lock 20 of FIG. 5 is preferred for use with a sliding door, including, for example, sliding glass doors that are often found at the rear side of houses having swimming pools. The keyless lock 20 is shown mounted in a sliding door 100 in FIG. 8 . In this embodiment, the keyless lock 20 includes a housing 120 mounted within the door 100 . The housing 120 is operably connected to a latching means 105 having a body 113 , an aperture 115 having multiple grooves, the aperture 115 central to the body 113 , and a hook-shaped arm 110 via a connecting means 55 . The latching means 113 is rotated back and forth between a locked position and an unlocked position via a knob 25 and the connecting means 55 . In this embodiment, the connecting means 55 is shown as a ribbed connecting rod 55 . Any suitable device or component for connecting the knob 25 to the latching means 105 , however, can be used. The connecting rod 55 has a first end that is attached to the knob 25 and a second end that protrudes through the multi-grooved aperture 115 of the latching means 105 and into the housing 120 . The knob 25 is attached to the first end of the connecting rod 55 by any suitable means (e.g., screws 35 that are screwed into screw holes 30 of the knob 25 ).
[0024] The keyless lock 20 shown in FIG. 6 also has a securing means 125 having a body 130 and a member 140 extending from the body 130 for securing the hook-shaped arm 110 of the latching means 105 . The securing means 125 is rigidly mounted to the appropriate portion of the door frame 15 (or doorjamb or wall) disposed opposite to the keyless lock. The securing means 125 is rigidly mounted to the door frame 15 (or door jamb or wall) via any suitable means (e.g., screw holes 135 and screws 145 driven therethrough). The lock 20 is positioned at an adequate distance 22 from the ground (e.g., 1.5 meters) such that a small child cannot reach the lock 20 . The lock 20 can include one means for locking and unlocking the lock (e.g., knob 25 ) mounted to one side of the door 10 , but preferably includes a first and a second means for unlocking the lock (e.g., two knobs 25 ), the first means mounted to the interior surface of the door and the second means mounted to the exterior surface of the door 10 . Having first and second means for unlocking and locking the lock is preferable because this allows the lock 20 to be operated from either side of the door 10 . The knob 25 can be any type of graspable implement but is preferably one that is easy to grasp and turn. The knob 25 can be made of any suitably rigid material, including metal, metal alloy, plastic, and composite materials thereof.
[0025] Operation of the keyless lock 20 shown in FIGS. 5 and 8 is illustrated in FIGS. 6 and 7 . FIG. 6 illustrates a keyless lock 20 in a locked position in which the hook-shaped arm 110 of the latching means 105 is disposed on the member 140 extending from the body 130 of the securing means 125 . The first end of the connecting rod 55 is shown positioned within the multi-grooved aperture 115 central to the body 113 of the latching means 105 . In this embodiment, the ribs of the ribbed connecting rod 55 mate with the grooves of the aperture 115 , thereby forming a gear in which the rotation of the latching means 105 is coupled to the rotation of the ribbed connecting rod 55 . The connecting rod 55 and latching means 105 are rotated via manipulation of the knob 25 , i.e., turning the knob from a resting position. When the connecting rod 55 is rotated clockwise, the ribs of the connecting rod 55 catch in the grooves of the aperture 115 of the body 113 of the latching means 105 and lift the hook-shaped arm 110 away from the member 140 ( FIG. 7 ) so that the hook-shaped arm 110 is no longer secured to the securing means 125 , thereby unlocking the door. To lock the door, the knob 25 is rotated in a counter-clockwise direction, thereby securing the hook-shaped arm 110 to the member 140 extending from the body 130 of the securing means 125 .
[0026] A variation of the keyless lock of FIGS. 5-8 is illustrated in FIG. 9 . In this embodiment, the keyless lock 20 includes a housing 120 mounted within a door. The housing 120 is operably connected to a knob 25 and a latching means 105 having a body 113 with a central aperture 115 , and a hook-shaped arm 110 . A portion of the knob 25 is passed through the aperture of the latching means 105 and protrudes into the housing 120 . The knob 25 , latching means 105 , and housing 120 are all securely connected such that rotating the knob 25 also rotates the latching means 105 and the housing 120 . The keyless lock 20 shown in FIG. 9 also has a securing means 125 having a body 130 and a member 150 extending from the body 130 for receiving the arm 110 of the latching means 105 . The securing means 125 is rigidly mounted to a portion of the door frame (or door jamb or wall) disposed at essentially the same distance from the ground as the knob 25 . The securing means 125 is rigidly mounted to the door frame (or door jamb or wall) by any suitable means. The latching means 105 is rotated back and forth between a locked position and an unlocked position via turning of the knob 25 . By rotating the knob 25 such that the arm 110 of the latching means 105 is disposed within the 150 member for receiving the arm 110 of the latching means 105 , the lock 20 is engaged and the door cannot be opened.
[0027] FIG. 10 illustrates another embodiment of the keyless lock 20 of FIG. 9 mounted in a sliding door 100 . In this embodiment, the securing means 125 is rigidly mounted to the portion of the door frame 15 (or door jamb) as shown.
[0028] A keyless lock of the invention is used to lock a door without requiring a key and without allowing small children to operate the lock. The invention thus provides a kit and a method for locking a door. An exemplary kit of the invention includes a first means for locking and unlocking the lock and a second means for locking and unlocking the lock that when installed in the door, the first means is positioned on the interior surface of the door and the second means is positioned on the exterior surface of the door. The kit also includes printed instructions for installing the keyless lock in the door at a distance from the bottom of the door of at least about 1.5 meters. An exemplary method of locking a door includes the steps of: (a) providing a door, (b) providing a keyless lock installed within the door, the keyless lock comprising a first means for locking and unlocking the lock and a second means for locking and unlocking the lock, the first means positioned on the interior surface of the door and the second means positioned on the exterior surface of the door, and (c) manipulating the first or the second means for locking and unlocking the lock.
[0029] From the foregoing, it can be appreciated that the keyless lock of the invention provides a system for preventing young children from opening doors while providing unfettered access to older children and adults. While the above specification contains many specifics, these should not be construed as limitations on the scope of the invention, but rather as examples of preferred embodiments thereof. Many other variations are possible. For example, the means for locking and unlocking the lock can be any suitable device in addition to a knob, including a handle or other graspable implement. As other examples, the knob may have a different shape, the connecting means can have a different shape, the locking bolt may have a different means for engaging the connecting means, and the spring may have a range of tensions. Different movements may be required to engage the means for locking and unlocking the lock (e.g., knob) and different movements of the means for locking and unlocking the lock (e.g., knob) may be required to cause the retraction of the locking bolt. Also, different securing and mounting arrangements can be used. Different techniques may be used to connect various components to one another. Such techniques may include, for example, molding, welding, use of adhesives, and press fitting. Furthermore, the general shapes and relative sizes of the various components may vary. Many different materials may be considered suitable for manufacturing the components described herein.
[0030] Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents. | What has been developed is a keyless door lock that prevents young children from opening doors their parents or caretakers do not wish them to open. The lock is a bolting mechanism type lock or a latching type lock having no keyed lock access side to it, but rather, a means for locking and unlocking the lock, such as a knob, on one or both sides of the door that when turned, unlocks the door. The lock is positioned within the door at a height that is unreachable by small children. The lock is useful for locking doors internal to the home (e.g., doors to medicine closets, cleaning supply closets, garage doors, doors at the top of stairs) as well as doors that provide access to the exterior of the home and therefore access to leave the premises of the home without supervision. Adults and older children, however, are never locked in or out of the room or house as no key is required for operating the lock, merely the turning of a knob. | 4 |
RELATED APPLICATION
[0001] This a continuation-in-part application claiming the priority benefit of application Ser. No. 09/358,696, filed Jul. 21, 1999, which is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to a steam humidifier used in HVAC systems in buildings.
BACKGROUND OF THE INVENTION
[0003] Since 1985, most steam humidifiers used steam injection manifolds that contain nozzles in the duct distributor pipes. The nozzles can be in the form of plain holes placed along the length of the pipe. This arrangement has been found to be unsatisfactory, since it allows the condensate to flow out of the holes into the airstream along with the steam. By using nozzles instead of plain holes that feed off the center of the pipe where the steam is hottest and driest, condensate is prevented from getting out with the steam.
[0004] However, it is labor intensive to install the nozzles into the steam distributor pipes, since holes must be drilled before the nozzles can be inserted into them and if a mistake is made on capacity, it is very difficult, if not impossible, to add nozzles to increase capacity. Exceeding the capacity of the nozzles results in a very heavy steam flow, which takes longer to evaporate in the airstream. In some cases, the nozzles used have been made of plastic and can come loose and leak or blow out of the distributor pipes.
[0005] To shorten the distance it takes for the steam to evaporate in the airduct, the number of distributor pipes have been increased to spread out the steam output over the entire cross-sectional area of the airduct. However, because there is now more surface of the distributor pipes exposed to the cold airstream, the result is usually more condensate production (which can be as much as 50% loss of the steam to condensate), loss of steam output, and heat-gain to the air in the airduct, which could be as much as 15° F. If the building is under cooling load, this heat-gain to the airstream will be detrimental to maintaining the building temperature.
[0006] In view of the above, there is, therefore, a need for a steam humidifier that avoids the shortcomings of the prior art.
OBJECTS AND SUMMARY OF THE INVENTION
[0007] It is an object of the present invention to provide a steam humidifier where the steam distributor pipes are provided with pressure variable apertures, instead of standard nozzles, that adjust their output to meet the demand.
[0008] It is another object of the present invention to provide a steam humidifier where the steam distributor pipes are installed to the manifold with slip fittings without tools, allowing the pipes to be easily disassembled and cut to fit the height of the airduct.
[0009] It is still another object of the present invention to provide a steam humidifier where the distributor pipes can be cut in the field to fit the height of the existing airduct without any detrimental effect to its steam distribution capacity.
[0010] It is another object of the present invention to provide a steam humidifier that can easily be retrofitted to switch to a different means of steam production, including direct steam, steam heat exchanger, electric coil, or gas-fired heat exchanger.
[0011] It is still another object of the present invention to provide a steam humidifier where the steam distributor pipes are insulated and where the nozzles are fed from the central part of the pipes where steam is hottest and driest, thereby minimizing production of condensate.
[0012] It is another object of the present invention to provide a steam humidifier where the contact ratio of steam to air is substantially 100%.
[0013] It is still another object of the present invention to provide a steam humidifier that minimizes spitting from condensate and facilitates flow of condensate toward the interior and bottom of the distributor pipes where the steam is hottest and driest to flash much of the condensate back to usable steam.
[0014] It is another object of the present invention to provide a steam humidifier having a distributor pipe with an initial slot opening width that opens wider in response to the demand for humidity.
[0015] It is still another object of the present invention to provide a humidifier that includes distributor pipes with insulated outside surfaces to minimize heat transfer to the airstream, particularly during the airconditioning season, and maintain the inside surfaces smooth to facilitate flow of condensate back to the manifold for re-evaporation to steam.
[0016] In summary, the present invention provides a humidifier for providing moisture to an airstream within an airduct, comprising a base manifold configured for being secured to a side of the airduct, the base manifold including a steam inlet valve and a condensate drain valve; and a distributor pipe secured to the base manifold and configured to extend into the airduct, the distributor pipe being in communication with the base manifold.
[0017] The present invention also provides a humidifier for providing moisture to an airstream within an airduct, comprising a base manifold configured for being secured to a side of the airduct; a heat-exchanger disposed within the base manifold configured to boil water disposed within the base manifold to steam; and a distributor pipe secured to the base manifold and configured to extend into the airduct, the distributor pipe being in communication with the base manifold.
[0018] The present invention further provides a nozzle for dispensing moisture into an airstream, comprising a pipe having a first end for connecting to a source of steam and a closed second end; first and second slots disposed opposite each other and longitudinally along a major portion of the length of the pipe; and the pipe being subject to flexing such that the slots open up in response to the steam being introduced thereinto, thereby to release steam in the airstream.
[0019] The present invention also provides a method for humidifying an airstream in a duct, comprising providing a nozzle configured to provide a sheet pattern of spray; disposing the nozzle in the airstream; connecting the nozzle to a source of steam; directing the steam sheet pattern transversely to the direction of the airstream such that maximum surface area of the sheet pattern is presented to the airstream.
[0020] Further, the present invention provides a humidifier for providing moisture to an airstream, comprising a pipe having a first end for connecting to a source of steam and a closed second end; first and second slots disposed opposite each other and longitudinally along a major portion of the length of the pipe; and a plurality of members sandwiched within the first and second slots, the members being disposed toward the interior of the pipe to guide condensate into the interior of the pipe.
[0021] The present invention also provides a humidifier for providing moisture to an airstream within an airduct, comprising a pipe having a first end for connecting to a source of steam and a closed second end; first and second slots disposed opposite each other and longitudinally along a major portion of the length of the pipe; and an insert sandwiched within the first and second slots to provide the slots an initial opening width. The pipe is subject to flexing such that the slots open up to greater than the initial opening width in response to the steam being released through the first and second slots.
[0022] These and other objects of the present invention will become apparent from the following detailed description.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0023] [0023]FIG. 1 is a schematic perspective view of a steam humidifier installed in an airduct with portions shown in cross-section and broken out.
[0024] [0024]FIG. 2 is a side elevational view, with a portions in cross-section of the steam humidifier of the present invention, under low or no-load conditions.
[0025] [0025]FIG. 3 is a cross-sectional view taken along line 3 - 3 of FIG. 6.
[0026] [0026]FIG. 4 is a side elevational view, with portions shown in cross-section of the steam humidifier under load conditions.
[0027] [0027]FIG. 5 is a cross-sectional view taken along line 5 - 5 of FIG. 7.
[0028] [0028]FIG. 6 is a view across the cross-section of the airduct, showing the steam humidifier in a low load or off conditions state.
[0029] [0029]FIG. 7 is a view across the cross-section of the airduct, showing the humidifier generating a sheet pattern of steam substantially perpendicular to the airflow.
[0030] [0030]FIG. 8 is an enlarged view of a portion of the distributor pipe showing a clamp assembly using the present invention.
[0031] [0031]FIG. 9 is a cross-sectional view taken along line 8 - 8 of FIG. 8.
[0032] [0032]FIG. 10 is a schematic perspective view of the humidifier of the present invention, showing a feed cap removed from the base manifold.
[0033] [0033]FIG. 11A is a schematic perspective view of a steam heat-exchanger for placement within the base manifold for generation of steam.
[0034] [0034]FIG. 11B is a schematic perspective view of an electric coil for placement within the base manifold for generation of steam.
[0035] [0035]FIG. 11C is a schematic perspective view of a gas-fired heat-exchanger for placement within the base manifold for generation of steam.
[0036] [0036]FIG. 12 is a schematic perspective view of another embodiment of a steam humidifier installed in an airduct with portions shown in cross-section and broken out.
[0037] [0037]FIG. 13 is a cross-sectional view taken along line 13 - 13 of FIG. 16.
[0038] [0038]FIG. 14 is a cross-sectional view similar to FIG. 13, but under increased load.
[0039] [0039]FIG. 15 is a perspective view of a structure used within the distributor pipes of the present invention.
[0040] [0040]FIG. 16 is a cross-sectional view taken along line 16 - 16 of FIG. 12.
[0041] [0041]FIG. 17 is an enlarged cross-sectional view of a portion of FIG. 16.
DETAILED DESCRIPTION OF THE INVENTION
[0042] A steam humidifier R made in accordance with the present invention is disclosed in FIG. 1. The humidifier R is operably associated with an airduct 2 in which an airstream 4 is maintained for the HVAC requirements of the building. Moisture is added to the airstream by means of the humidifier R to maintain the building air at some humidity levels.
[0043] The steam humidifier R comprises a base manifold 6 , preferably disposed outside the airduct 2 . A plurality of steam distributor pipes 8 are disposed within the airduct 2 and are operably connected to the base manifold 6 . Each distributor pipe communicates with the base manifold through a respective opening 7 , as best shown in FIG. 2. Each steam distributor pipe 8 functions as a nozzle, dispensing steam into the airstream 4 .
[0044] Steam is supplied to the base manifold 6 through a valve 10 which may be controlled by a humidity sensor (not shown) or other standard controller. Condensate collects in the base manifold 6 and is drained out through a standard steam trap 12 , which allows condensate to drain out to drain tube 13 but not the steam. The base manifold 6 separates the incoming steam from the condensate flowing down from the distributor pipe 8 .
[0045] Each distributor pipe 8 is made from two half-pipe sections 14 , as best shown in FIGS. 2 and 3. Each section 14 has inwardly directed flange portions 16 that define a slot 18 with the opposing flange portion 16 in the other half-pipe section 14 . The flange portions 16 advantageously extend the slots 18 into the central portion of the distributor pipe 8 where the steam is driest to prevent condensate release into the airduct 2 , which can cause wetting on the bottom of the airduct.
[0046] An insulating jacket 20 is disposed on the inside arcuate surface of each half-pipe section 14 to advantageously reduce condensate production, generally indicated at 21 , thereby improving efficiency. The insulating jacket 20 also advantageously reduces the heat gain to the airduct, minimizing interference with the airconditioning system. Further, since the insulating jacket 20 is internal, no rubber or plastic parts are exposed to the airstream.
[0047] The insulating jacket 20 can be either a liquid applied during assembly or a loose sleeve of material slip into each half-pipe section. Silicon rubber is preferable since it holds up to the steam and provides a slick surface for the condensate to run down back to the base manifold 6 where it is collected.
[0048] The two half-pipe sections 14 are held together by a slip fitting connector 22 . The connector 22 is made from a pipe and secured by standard means to the base manifold 6 . An end cap 24 is used to secure the other end of the two half-pipe sections 14 , as best shown in FIG. 2. The two half-pipe sections 14 are advantageously fit together with the connector 22 and the end cap 24 without tools, so that the half-pipes can be easily disassembled and be cut to size if needed in the field on a factory floor to permit customization of the size to fit the airduct.
[0049] Steam is discharged through the slot 18 , creating a sheet of steam substantially 90° to the airstream, as best shown in FIGS. 5 and 7. The airstream then turns the sheet and carries it downstream and is absorbed. The contact ratio of steam to air is about 100%, advantageously providing maximum absorption by the airstream.
[0050] Each distributor pipe 8 is preferably made from a light gauge stainless steel configured to flex as steam pressure is applied inside the pipe, causing the slots to open or close with the steam flow, thereby providing a variable aperture that will ensure equal distribution over the entire length of the base manifold 6 and therefore the best steam distribution to the airstream within the airduct 2 , as best shown in FIGS. 4, 5 and 7 .
[0051] Under low flow conditions, the slots 18 are mostly closed, ensuring equal steam output over the entire length of the distributor pipe 8 . Under high flow condition, the distributor pipe 8 will flex open from the middle, advantageously putting most of the steam in the center of the airstream where it can be most readily absorbed.
[0052] Steam enters the distributor pipe 8 from the base manifold 6 and flows upwardly through the openings 7 , passing over condensate 21 returning downwardly to the base manifolds 6 , as best shown in FIG. 5. The cross-flow operation results in much of the condensate 21 flashing the back into usable steam, as the condensate contacts the rising hot steam.
[0053] A spring loaded clamp assembly 28 can be used to advantageously control the flexing of the half-pipe sections 14 during high flow conditions, as best shown in FIGS. 8 and 9. The clamp assembly 28 includes a band 30 with a pair of diametrically opposed springs 32 that are so disposed as to urge the two half-pipe sections 14 towards each other, thereby to control the opening of the slots 18 . The springs 32 and the diameter of the band 30 can be sized to provide more or less flex to the half-pipe sections 14 .
[0054] The clamp assembly 28 is preferably disposed at the middle of the distributor pipe 8 where maximum flex occurs and, therefore, where maximum control is required.
[0055] The base manifold 6 can be made from standard stainless steel pipe with a flanged end bell at one end and a feed bell 34 at the other end, as best shown in FIG. 1. The feed bell 34 can easily be removed if retrofitting is required to change the humidifier to a different steam source. A direct steam embodiment is shown in FIGS. 1, 4 and 10 , where steam, generated remotely in a boiler, is directly fed into the base manifold 6 and to the several distributor pipes 8 .
[0056] A steam-to-steam heat exchanger 36 is disclosed in FIG. 11A. A steam valve 38 is operably connected to a steam source and feeds it to a heat exchanger coil 40 , which is adapted to be disposed within the base manifold 6 . The other end of the heat exchanger coil 40 is connected to steam trap 42 that permits condensate to drain out but keeps the steam in. A water inlet valve 44 fills the base manifold 6 to an operating level and is controlled by a float or other standard means. A water drain valve 46 permits periodic draining of the base manifold 6 to advantageously reduce mineral build-up. Heat from the coil 40 boils the water to create steam.
[0057] In another embodiment, steam generation is provided by a set of electric coils 48 configured to fit within the base manifold 6 , as best shown in FIG. 11B. A switch 50 , controlled by standard means such as a humidity sensor, turns the electric col 48 on and off to generate steam as needed.
[0058] Steam generation may also be provided by a gas-fired heat exchanger 51 , as best shown in FIG. 11C. Hot flue gas from gas combustion is forced into a heat exchanger coil 53 to boil the water inside the base manifold 6 . A gas valve 52 , controlled by standard means, is operably connected to a burner 54 which fires into the coil 53 , which functions as a flue pipe. An exhaust pipe 56 is operably connected to the coil 53 to vent the products of combustion.
[0059] The various means for providing steam for humidification makes the humidifier R advantageously flexible so that the user can easily retrofit the humidifier to a different source of steam to meet his changing needs. For example, the user may start with a direct steam embodiment, where steam is generated remotely from the apparatus. If the boiler treatment chemicals later become a problem, the user can change to a steam or electric heat exchanger or to a gas fired heat exchanger by simply removing the feed bell 34 and inserting within the base manifold 6 one of the heat exchangers disclosed herein.
[0060] Mounting collars 58 are used to secure the system R to the airduct 2 , as best shown in FIG. 2. Each mounting collar 58 may be made from a steel plate which is then secured by conventional means to the connector 22 . Standard fasteners are used to secure the collars 58 to the underside of the airduct 2 .
[0061] In another embodiment of the present invention, each distributor pipe 8 is provided with an insulating layer 60 disposed on the outside arcuate surface of each half-pipe section 14 , as best shown in FIGS. 12, 13 and 14 . The insulation coating 60 is a ceramic coating sold under the trademark CERAMIC-COVER, made by Therma-Coat, Inc., Chamblee, Ga. 30341. The insulation coating 60 is preferably applied directly unto the exterior surfaces of each distributor pipe 8 by spraying. The insulation coating 60 advantageously maintains the outside temperature of the distributor pipes 8 to about less than 120° F., thereby minimizing heat transfer to the airstream during airconditioning season and to minimize condensate production. By disposing the insulation coating 60 on the outside surfaces of the distributor pipes 8 , the inside surfaces remain smooth to facilitate the condensate to flow down back to the base manifold 6 where it is collected and re-evaporated.
[0062] A condensate structure 62 is disposed within the slots 18 formed by the opposing flange portions 16 , as best shown in FIGS. 13, 15, and 16 . The structure 62 functions as a wick to collect any condensate forming in the area of the slots 18 and to facilitate flow back toward the center and bottom of the distributor pipes 8 for re-evaporation by the relatively hotter steam coming up from the manifold 6 . The condensate is generally indicated at 63 in FIG. 17. The structure 62 is shaped like a tree with a central member 64 disposed within the central interior of the pipes 8 and a plurality of side members 66 directed downwardly toward the central member 64 and the bottom of the pipes 8 . The side members 66 are advantageously oriented downwardly toward the central member 64 to aid in directing the flow of the condensate 63 toward the central member 64 . The ends of the side members 66 overlap the flange portions 16 . The structure 62 is preferably made of stainless steel or any other suitable material. The structure 62 is preferably sized to extend the length of the distributor pipes 8 , as best shown in FIG. 16. The structure 62 is secured by conventional means, such as by tack welding to the flange portions 16 . The structure 62 , which provides the means for guiding condensate toward the interior and bottom of the pipes 8 where the condensate is re-evaporated when it comes in contact with the relatively hotter and drier steam, advantageously increases the efficiency of the humidifier and eliminates spitting, which is condensate being ejected through the slots 18 .
[0063] The thickness of the structure 62 provides the slots 18 with an initial opening width through which the steam can exit, as generally indicated by the arrows 68 in FIGS. 13 and 17. As the demand increases for humidity and steam pressure is increased into the manifold 6 , the distributor pipes 8 will flex open from the middle, due to thermal expansion and increased pressure of the steam, increasing the gap of slots 18 to greater than the initial width, as best shown in FIG. 14.
[0064] While this invention has been described as having preferred design, it is understood that it is capable of further modification, uses and/or adaptations following in general the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features set forth, and fall within the scope of the invention or the limits of the appended claims. | A humidifier for providing moisture to an airstream comprises a pipe having a first end for connecting to a source of steam and a closed second end; first and second slots disposed opposite each other and longitudinally along a major portion of the length of the pipe; and a plurality of members sandwiched within the first and second slots, the members being disposed toward the interior of the pipe to guide condensate into the interior of the pipe. | 8 |
[0001] This is a continuation of Application PCT/JP2003/001010, filed on Jan. 31, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention relates to a printed wiring board and an electronic apparatus including the printed wiring board.
[0004] 2. Background Art
[0005] In a printed board on which a high-speed element is mounted, there are problems in that a high frequency current flows into a power supply layer and a ground layer, with the result that resonance occurs and an unnecessary electromagnetic wave is emitted. Up to now, a configuration to which a circuit using a resistor and a magnetic material is added has been employed to suppress the resonance.
[0006] However, such a method is disadvantageous in taking measures for packaging in a narrow space. The use of the resistor and the magnetic material increases the number of parts.
[0007] Up to now, for resonance measures or noise measures, high-frequency connection is made between the power supply layer and the ground layer through a chip capacitor or the like and charges are supplied to the element.
[0008] However, in recent years, with increases in frequency and packaging density in a device, effects obtained by the above-mentioned measures have been reduced due to inductance components of patterns and vias for packaging. In order to prevent this, attention has been focused on a substrate in which flat pattern layers on a circuit board are assumed as electrodes to form a capacitor (buried capacitance board, briefly referred to as a BC board). In addition, it has been proposed to locate a signal layer including a signal line, which is sandwiched by two ground layers (for example, see Patent Document 1 below).
[0009] Note that general structures of a multilayer printed board, for example, a via connecting between printed boards, a through hole, a clearance hole for ensuring insulation between the via and the printed board, and the like are described in, for example, Patent Document 2 below.
[0000] [Patent Document 1] JP 2001-223449 A
[0000] [Patent Document 2] JP 05-152763 A
SUMMARY OF THE INVENTION
[0010] However, a capacitance of the capacitor of the currently-available buried capacitance board is insufficient. Therefore, there is a problem in that an impedance of about several tens of MHz becomes higher to reduce a bypass effect. Therefore, the following measure methods are expected.
[0011] According to a first measure, it is expected to improve a dielectric constant of a dielectric composing the capacitor. However, a material whose dielectric constant is improved is generally expensive. A high dielectric constant material is not easily available in many cases.
[0012] According to a second measure, it is expected to reduce a thickness of the dielectric composing the capacitor. However, when the dielectric is too thin, a withstand voltage between the power supply layer and the ground layer reduces and they are short-circuited at worst. In addition, when the dielectric is too thin, handling thereof is hard.
[0013] According to a third measure, it is expected to increase an area of the capacitor. This corresponds to an increase in area of the printed board or an increase in area of a capacitor portion in the printed board. However, because of a limitation of size of a device, the area of the capacitor portion in the printed board is limited in many cases.
[0014] The present invention has been made in view of such problems of the conventional technologies. That is, an object of the present invention is to improve characteristics of the buried capacitance board.
[0015] More specifically, an object of the present invention is to improve a capacitance of a capacitor in a packaging method using the buried capacitance board. Further, an object of the present invention is to suppress a board resonance phenomenon in a packaging method using the buried capacitance board.
[0016] In order to achieve the above-mentioned objects, the present invention adopts the following measures. That is, the present invention relates to a multilayer printed board, including:
[0017] a plurality of capacitive coupling layers, each of which includes a power supply layer and a ground layer which are opposed to each other and a dielectric layer which is sandwiched therebetween;
[0018] a first via that connects between the power supply layers included in the plurality of capacitive coupling layers; and
[0019] a second via that connects between the ground layers included in the plurality of capacitive coupling layers.
[0020] Therefore, according to the present invention, the plurality of capacitive coupling layers are provided, the power supply layers included in the respective capacitive coupling layers are connected with each other, and the ground layers included in the respective capacitive coupling layers are connected with each other. Thus, a capacitance of each of the capacitive coupling layers can be increased to reduce an impedance in a low frequency domain in which a frequency is low.
[0021] Preferably, in the multilayer printed board, a power supply via that connects a power supply terminal of an element with the power supply layers may be formed near a central axis passing through a substantially central portion of a flat region of each of the capacitive coupling layers.
[0022] Alternatively, the present invention may relate to a multilayer printed board, including:
[0023] a capacitive coupling layer that includes a power supply layer and a ground layer which are opposed to each other and a dielectric layer which is sandwiched therebetween;
[0024] an element layer on which an element to which power is supplied from the power supply layer is mounted; and
[0025] a via that is formed close to a central axis passing through substantially a central portion of a flat region of the capacitive coupling layer and connects a power supply terminal of the element with the power supply layer.
[0026] Therefore, the multilayer printed board of the present invention has a via which is located near the central axis passing through the substantially central portion of the flat region of the capacitive coupling layer. A power supply terminal of the element is connected with the power supply layer. The element is desirably an element having a high-speed operating frequency in multilayer printed board. A high frequency wave is supplied from the element to the power supply layer through the via. However, the via is formed near the central axis, so that resonance dependent on a size of the capacitive coupling layer can be reduced.
[0027] Preferably, the number of at least one of the first via and the second via is two or more. Therefore, when the number of at least one of the first via and the second via is set to two or more, resonance points of which the number increases with an increase in capacitance of the capacitive coupling layer can be shifted to a high frequency side.
[0028] Preferably, the power supply layer and the ground layer in each of the plurality of capacitive coupling layers may be laminated in the same arrangement order.
[0029] Preferably, the power supply layer and the ground layer in a first capacitive coupling layer of the plurality of capacitive coupling layers may be laminated in an arrangement order reverse to an arrangement order of those in a second capacitive coupling layer thereof. That is, the present invention has no limitations on the arrangement order of the power supply layer and the ground layer.
[0030] Preferably, the power supply layer and the ground layer may form a capacitive coupling layer over an entire region of the dielectric layer.
[0031] Preferably, the power supply layer and the ground layer may form a capacitive coupling layer in a partial region of the dielectric layer.
[0032] Preferably, a flat shape of at least one of the power supply layer and the ground layer may be substantially a regular polygon having sides whose number is equal to or larger than five.
[0033] Preferably, a flat shape of at least one of the power supply layer and the ground layer may be substantially a circle.
[0034] Preferably, a ratio of a longest distance to a shortest distance between a central portion and a peripheral portion of a flat shape of at least one of the power supply layer and the ground layer thereof is 1 to 1.41.
[0035] According to the present invention, any structure described above may be used for an electronic apparatus provided with a multilayer printed board.
[0036] As described above, according to the present invention, the characteristics of the capacitive coupling layer can be improved to shift the resonance point to a high frequency domain.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 is a perspective view showing a multilayer printed board according to a first embodiment mode of the present invention;
[0038] FIG. 2 is a front view showing the multilayer printed board according to the first embodiment mode of the present invention;
[0039] FIG. 3 is a front view showing an analytical model of a multilayer printed board according to Embodiment 1;
[0040] FIG. 4 is a plan view showing positions of a power supply pin of an LSI 1 , power supply vias 7 A and 7 B, and ground vias 8 , which are mounted on the multilayer printed board according to Embodiment 1;
[0041] FIG. 5 shows an impedance analytical result of a BC board 6 shown in FIG. 4 ;
[0042] FIG. 6 shows an impedance analytical result ( 1 ) in the case where the number of BC layers 6 is changed;
[0043] FIG. 7 shows an impedance analytical result ( 2 ) in the case where the number of BC layers 6 is changed;
[0044] FIG. 8 shows the position of the power supply pin of the LSI 1 (power supply via 7 A) and the positions of the power supply vias 7 B and the ground vias 8 in Embodiment 2;
[0045] FIG. 9 shows a frequency characteristic of an impedance of the BC layer 6 in Embodiment 2;
[0046] FIG. 10 shows the position of the power supply pin of the LSI 1 (power supply via 7 A) and the positions of the power supply vias 7 B and the ground vias 8 in Embodiment 3;
[0047] FIG. 11 shows a frequency characteristic of an impedance of the BC layer 6 in Embodiment 3;
[0048] FIG. 12 is a perspective view showing a multilayer printed board according to a modified example of the first embodiment mode;
[0049] FIG. 13 is a front view showing the multilayer printed board according to the modified example of the first embodiment mode;
[0050] FIG. 14 is a perspective view showing a multilayer printed board according to a second embodiment mode;
[0051] FIG. 15 is a front view showing the multilayer printed board according to the second embodiment mode;
[0052] FIG. 16 is an explanatory view of a natural resonance frequency of a printed board;
[0053] FIG. 17 shows a summary of Embodiment 4 of the present invention;
[0054] FIG. 18 shows superposition of results obtained by measurement in Embodiment 4;
[0055] FIG. 19 shows an analytical result ( 1 ) of a current distribution;
[0056] FIG. 20 shows an analytical result ( 2 ) of a current distribution;
[0057] FIG. 21 shows an analytical result ( 3 ) of a current distribution;
[0058] FIG. 22 shows an analytical result ( 4 ) of a current distribution;
[0059] FIG. 23 shows an analytical result ( 5 ) of a current distribution;
[0060] FIG. 24 shows an analytical result ( 6 ) of a current distribution;
[0061] FIG. 25 shows respective states of the BC layer 6 in the case where the power supply via 7 (power supply pin 17 of the LSI 1 ) is shifted from a central position in the direction of a side of a rectangle composing the BC layer;
[0062] FIG. 26 shows a result obtained by analyzing horizontal polarization of a radiation electric field strength with respect to the respective states shown in FIG. 25 ;
[0063] FIG. 27 shows a result obtained by analyzing vertical polarization of a radiation electric field strength with respect to the respective states shown in FIG. 25 ;
[0064] FIG. 28 shows respective states of the BC layer 6 in the case where the power supply via 7 (power supply pin 17 of the LSI 1 ) is shifted from the central position in a vertex direction of the rectangle composing the BC layer;
[0065] FIG. 29 shows a result obtained by analyzing horizontal polarization of a radiation electric field strength with respect to the respective states shown in FIG. 28 ;
[0066] FIG. 30 shows a result obtained by analyzing vertical polarization of a radiation electric field strength with respect to the states shown in FIG. 28 ;
[0067] FIG. 31 shows a multilayer printed board having the BC layer 6 with a rectangular shape of 25 mm square;
[0068] FIG. 32 shows a result ( 1 ) obtained by analyzing horizontal polarization of a radiation electric field strength with respect to the multilayer printed board shown in FIG. 31 ;
[0069] FIG. 33 shows a result ( 1 ) obtained by analyzing vertical polarization of a radiation electric field strength with respect to the multilayer printed board shown in FIG. 31 ;
[0070] FIG. 34 shows a result ( 2 ) obtained by analyzing horizontal polarization of a radiation electric field strength with respect to the multilayer printed board shown in FIG. 31 ;
[0071] FIG. 35 shows a result ( 2 ) obtained by analyzing vertical polarization of a radiation electric field strength with respect to the multilayer printed board shown in FIG. 31 ;
[0072] FIG. 36 is a perspective view showing a multilayer printed board according to a third embodiment mode of the present invention;
[0073] FIG. 37 is a front view showing the multilayer printed board according to the third embodiment mode of the present invention;
[0074] FIG. 38 shows comparison between the BC layer 16 in the third embodiment mode and the BC layer in the first embodiment mode or the second embodiment mode;
[0075] FIG. 39 shows impedance analytical results in the case where the power supply via 7 is located near a central axis of a rectangular BC layer of 50 mm square and in the case where the power supply via 7 is located near a central axis of a circular BC layer 16 having a diameter of 50 mm;
[0076] FIG. 40 shows BC layers each having a flat shape of a regular polygon such as a regular octagon, a regular hexadecagon, or a regular triacontakaidigon;
[0077] FIG. 41 shows frequency characteristics with respect to an impedance between the power supply layer and the ground layer in each of the BC layers each having a flat shape such as a square, the regular octagon, the regular hexadecagon, or the regular triacontakaidigon;
[0078] FIG. 42 shows an analytical result ( 1 ) of a current density in a rectangular BC layer at a vicinity of a resonance point;
[0079] FIG. 43 shows an analytical result ( 2 ) of a current density in the rectangular BC layer in the vicinity of the resonance point;
[0080] FIG. 44 shows a current distribution of a high frequency current in an octagonal BC layer;
[0081] FIG. 45 shows a current distribution of a high frequency current in a triacontakaidigonal BC layer;
[0082] FIG. 46 shows an analytical result of a radiation electric field strength in rectangular, regular octagonal, regular hexadecagonal, and regular triacontakaidigonal BC layers at the time of resonance;
[0083] FIG. 47 shows a structure of an electric apparatus 100 according to a fourth embodiment mode of the present invention;
[0084] FIG. 48 shows a shape of the BC layer according to a modified example of the first to third embodiment modes;
[0085] FIG. 49 shows a layer structure of an analytical model of a multilayer print according to the second and third embodiment modes; and
[0086] FIG. 50 shows observation points for the radiation electric field strength in the analytical mode of the multilayer print according to the second and third embodiment modes.
DETAILED DESCRIPTION OF THE INVENTION
[0087] Hereinafter, preferred embodiment modes of the present invention will be described with reference to the drawings.
First Embodiment Mode
[0088] Hereinafter, a multilayer printed board according to a first embodiment mode of the present invention will be described with reference to FIG. 1 to FIG. 13 .
[0000] <Structure>
[0089] FIG. 1 is a perspective view showing an example of the multilayer printed board. FIG. 2 is a front view in the case where the multilayer printed board is viewed from a direction indicated by an arrow A in FIG. 1 . As shown in FIG. 1 or FIG. 2 , the multilayer printed board includes an element such as an LSI 1 , printed boards 2 - 1 , 2 - 2 , and 2 - 3 , each of which has a signal layer connected with the element, and BC layers 6 located between the printed boards 2 - 1 and 2 - 2 and the printed boards 2 - 2 and 2 - 3 .
[0090] The printed boards 2 - 1 , 2 - 2 , 2 - 3 , etc. each are composed of a single or plural printed boards. In the case of plural items, they are referred to as multiple layers 2 - 1 , 2 - 2 , 2 - 3 , etc. In general, each of the printed boards 2 - 1 , 2 - 2 , 2 - 3 , etc. includes a conductive layer (this is referred to as the signal layer) connected with the element such as the LSI 1 .
[0091] The BC layers 6 each are composed of a power supply layer 3 , a thin film dielectric 4 , and a ground layer 5 .
[0092] The power supply layer 3 is connected with a power supply located outside the multilayer printed board and used to supply power to the element mounted on the multilayer printed board. The power supply layer 3 is formed from a metallic thin film formed into a rectangular sheet. The metallic thin film is also referred to as a flat pattern layer. A copper thin film is generally used as a metallic film composing the power supply layer 3 . Note that a metal such as aluminum, silver, platinum, and gold may be used if necessary.
[0093] The ground layer 5 is connected with an earth located outside the multilayer printed board and used as a layer for grounding the element mounted on the multilayer printed board. As in the case of the power supply layer 3 , the ground layer 5 is formed from a metallic thin film made of copper or the like. The ground layer is also formed into a rectangular sheet and referred to as a flat pattern layer.
[0094] The thin film dielectric 4 is a dielectric layer inserted between the power supply layer 3 and the ground layer 5 . The thin film dielectric 4 is used to increase a dielectric constant of a portion sandwiched between the power supply layer 3 and the ground layer 5 to improve a function as a capacitor. Such a board which is composed of the power supply layer 3 , the thin film dielectric 4 , and the ground layer 5 is known as a buried capacitance board (or a BC board).
[0095] In this embodiment mode, for example, polyimide, Fr-4 (glass epoxy), or ceramic can be used for the thin film dielectric 4 .
[0096] The multilayer printed board according to this embodiment mode has the plurality of BC layers 6 (two BC layers 6 are shown in FIG. 1 and FIG. 2 ).
[0097] As shown in FIG. 2 , the power supply layers 3 included in the respective BC layers 6 are connected with each other through a power supply via 7 . The power supply via 7 passes through the uppermost printed board 2 - 1 including the signal layer and is connected with a power supply pin of the LSI 1 .
[0098] In general, when the via is formed, a hole is formed in the printed board (metallic thin film and the dielectric which is its lower layer) and an inner wall of the hole is coated with a metal. The via is used to connect, for example, between the printed board 2 - 1 and another printed board, between the printed board 2 - 1 and the power supply layer 3 , or between the printed board 2 - 1 and the ground layer 5 . The LSI 1 is located on the printed board 2 - 1 such that the power supply pin thereof is adjacent to the power supply via 7 .
[0099] With respect to the printed boards 2 - 1 , 2 - 2 , and 2 - 3 , the power supply layer 3 , or the ground layer 5 , which are not connected with the via, a hole having a shape larger than an outer diameter of the via (this is referred to as a clearance hole) is provided at a position in which the via is formed.
[0100] Therefore, an arbitrary layer included in the multilayer printed board can be connected with another layer by a combination of the via and the clearance hole (for example, see Patent Document 2 above). In this embodiment mode, an outer diameter (diameter of a conductor surface which is in contact with the hole of the printed board) of the power supply via 7 is 0.3 millimeters and an inner diameter of the clearance hole is about 0.9 millimeters.
[0101] As shown in FIG. 2 , the ground layers 5 included in the respective BC layers 6 are connected with each other through a ground via 8 to ground the printed board 2 - 1 , 2 - 2 , or 2 - 3 and the element (such as the LSI 1 ).
[0102] When such a structure is used for the multilayer printed board according to this embodiment mode, the plurality of power supply layers 3 are connected with each other through the power supply via 7 . In addition, in the multilayer printed board, the plurality of ground layers 5 are connected with each other through the ground via 8 .
[0103] Thus, according to the multilayer printed board of the present invention, a sufficient capacitance is ensured in each of the BC boards 6 . In this multilayer printed board, the power supply via 7 or the ground via 8 is not limited to a single via. That is, in the multilayer printed board of the present invention, a plurality of power supply vias 7 or a plurality of ground vias 8 are provided to improve a frequency characteristic of each of the BC boards 6 .
Embodiment 1
[0104] FIG. 3 and FIG. 4 show a structure of a multilayer printed board according to Embodiment 1 of the present invention. In this embodiment, numerical analytical results obtained by calculation of a modeled multilayer printed board are shown. FIG. 3 is a front view showing an analytical model in the case where the multilayer printed board is viewed from the front (for example, the direction indicated by the arrow A in FIG. 1 ) as in FIG. 2 .
[0105] As shown in FIG. 3 , the multilayer printed board includes an insulator 2 A, a power supply layer 3 - 1 , a thin film dielectric 4 - 1 , a ground layer 5 - 1 , an insulator 2 B, a power supply layer 3 - 2 , a thin film dielectric 4 - 2 , a ground layer 5 - 2 , and an insulator 2 C. Note that a signal layer is formed on an upper side of the insulator 2 A or a lower side of the insulator 2 B in an original multilayer printed board. In this embodiment, the influence of the signal layer is not considered for the simplification of the model.
[0106] Each of the insulators 2 A and 2 C is a dielectric which has a dielectric constant of 3.2 and a thickness of 50 micrometers. The insulator 2 B is a dielectric which has a dielectric constant of 3.2 and a thickness of 100 micrometers. Each of the thin film dielectrics 4 - 1 and 4 - 2 is a dielectric which has a dielectric constant of 3.2 and a thickness of 25 micrometers. In FIG. 3 , the dielectric constant is shown by symbol Er.
[0107] In Embodiment 1 of the present invention, the power supply layer 3 - 1 and the power supply layer 3 - 2 are connected with each other through a power supply via 7 B. The ground layer 5 - 1 and the ground layer 5 - 2 are connected with each other through a ground via 8 .
[0108] The power supply via 7 B is a copper wire that connects the power supply layer 3 - 1 with the power supply layer 3 - 2 and has a diameter of 0.3 mm and conductivity of 5.977286×10 7 . The ground via 8 is a copper wire that connects the ground layer 5 - 1 with the ground layer 5 - 2 and has a diameter of 0.3 mm and conductivity of 5.977286×10 7 .
[0109] A clearance hole having a rectangular shape of 0.98 mm square is provided around each of the vias in layers which are not connected with the vias (power supply via 7 B and ground via 8 ). Assume that air surrounds the multilayer printed board.
[0110] A virtual wave source (high frequency voltage source) is set between the power supply layer 3 - 1 and the ground layer 5 - 1 and a current flowing thereinto is calculated. At this time, a via that connects the wave source with the power supply layer 3 - 1 and the ground layer 5 - 1 is referred to as a power supply via 7 A. The power supply via 7 A is originally a via that connects the power supply pin of the LSI 1 with the power supply layer 3 - 1 . However, in order to simply calculate an impedance between the power supply layer 3 - 1 and the ground layer 5 - 1 , the wave source is set between the power supply layer 3 - 1 and the ground layer 5 - 1 .
[0111] Here, a high frequency signal from the wave source is a trapezoid waveform whose rise time and fall time are each 500 ps, whose period is 100 MHz, and whose amplitude is 3.3 volts. In the analysis in this embodiment mode, various high frequency signals are inputted based on Fourier spectrum of the trapezoid waveform.
[0112] FIG. 4 is a plan view showing positions of the power supply pin of the LSI 1 , the power supply vias 7 A and 7 B, and the ground via 8 , which are mounted on the multilayer printed board (view in the case where the multilayer printed board is viewed from a direction indicated by an arrow B in FIG. 3 ). Note that FIG. 4 shows five cases (V 1 G 1 - 1 to V 1 G 1 - 5 ) in which the positions of the power supply via 7 B and the ground via 8 are shifted.
[0113] In FIG. 4 , any case of V 1 G 1 - 1 to V 1 G 1 - 5 , the power supply pin of the LSI 1 is positioned in a central portion of the BC layer 6 . As described above, in the multilayer printed board according to Embodiment 1, the power supply via 7 A and the wave source are formed just below the power supply pin and between the power supply layer 3 - 1 and the ground layer 5 - 1 (see FIG. 3 ).
[0114] Each of five heavy rectangles indicated by V 1 G 1 - 1 to V 1 G 1 - 5 shows an existing region of the BC layer 6 and is a rectangle of 25 millimeters square.
[0115] In FIG. 4 , mesh portions within each of the heavy rectangles indicated by V 1 G 1 - 1 to V 1 G 1 - 5 (such as M 1 and M 2 ) show element regions for numerical analysis. Note that the reason why each of the mesh portions in the four corners of each of the heavy rectangles (V 1 G 1 - 1 to V 1 G 1 - 5 ) is divided into two triangles as in the case of M 2 is to ensure analytical precision.
[0116] V 1 G 1 - 1 shows the case where the power supply via 7 B and the ground via 8 are provided on the left side of the power supply pin of the LSI 1 . Here, the left side is the left in the case where FIG. 4 is viewed from the front (hereinafter, the right side, the upper side, and the lower side are the same as above).
[0117] V 1 G 1 - 2 shows the case where the power supply via 7 B and the ground via 8 are further added on the right side of the power supply pin of the LSI 1 as compared with the case V 1 G 1 - 1 .
[0118] V 1 G 1 - 3 shows the case where the power supply via 7 B and the ground via 8 are further added on the upper side of the power supply pin of the LSI 1 as compared with the case V 1 G 1 - 2 .
[0119] V 1 G 1 - 4 shows the case where the power supply via 7 B and the ground via 8 are further added on the lower side of the power supply pin of the LSI 1 as compared with the case V 1 G 1 - 3 .
[0120] V 1 G 1 - 5 shows the case where the two power supply vias 7 B and the two ground vias 8 are further added as compared with the case V 1 G 1 - 4 .
[0121] FIG. 5 shows an analytical result of an impedance of the BC board 6 (between the power supply layer 3 and the ground layer 5 ) in the five cases (V 1 G 1 - 1 to V 1 G 1 - 5 ) as shown in FIG. 4 .
[0122] This analytical result is obtained by applying the electromagnetic analysis program ACCUFIELD® produced by FUJITSU LIMITED to the analytical model shown in FIG. 3 and FIG. 4 . The ACCUFIELD® is an electromagnetic analysis program in which a piecewise sinusoidal moment method (also called a moment method) is combined with a distributed constant transmission line theory.
[0123] In this numerical analysis, a rectangular sheet of 25 mm square (conductor sheet having conductivity of 5.977286×10 7 ) is provided for each of the power supply layers 3 - 1 and 3 - 2 and the ground layers 5 - 1 and 5 - 2 as shown in FIG. 3 . Each rectangular sheet is divided into, for example, the mesh portions M 1 and M 2 shown in FIG. 4 .
[0124] A high frequency power supply is set to a position of the wave source shown in FIG. 3 to obtain currents flowing through the respective mesh portions of each layer (each rectangular sheet) through the power supply vias 7 A and 7 B and the ground via 8 .
[0125] As described above, in this embodiment, the currents are calculated by the electromagnetic analysis program run on a computer. In a structure in which the single BC layer 6 is used, the power supply layer is connected with the power supply via, and the ground layer is connected with the ground via, a result is obtained in which values obtained by analysis using the electromagnetic analysis program coincide with measured values.
[0126] FIG. 5 shows an impedance analytical result. In FIG. 5 , the abscissa indicates a frequency and the ordinate indicates an impedance. Here, analytical results with respect to the respective analytical models V 1 G 1 - 1 to V 1 G 1 - 5 shown in FIG. 4 are shown using different graphs.
[0127] As shown in FIG. 5 , each of the models V 1 G 1 - 1 to V 1 G 1 - 5 exhibits a W-shaped characteristic or a characteristic in which a plurality of V-shapes are connected with one another. For example, in the case of V 1 G 1 - 1 , the impedance characteristic starts from a left end point S 1 and falls down to a lower right position P 1 in a frequency range of about 50 MHz to 210 MHz.
[0128] Next, the impedance characteristic rises up to an upward position P 2 in a frequency range of about 210 MHz to 350 MHz. Then, the impedance characteristic falls down to a downward position P 3 in a frequency range of about 350 MHz to about 650 MHz. Then, the impedance characteristic rises up to P 4 in a frequency range of about 650 MHz to 850 MHz.
[0129] In the impedance characteristic, each of peaks such as P 1 , P 2 , and P 3 indicates a resonance point. In general, when an element is mounted on a board, it is desirable to avoid the use of an element having an operating frequency (for example, a clock cycle) close to a resonance frequency because this becomes a cause of malfunction or the like.
[0130] For example, in the multilayer printed board including the BC layer 6 having the impedance characteristic shown in FIG. 5 , an element having a clock cycle of a range of S 1 to P 1 , P 2 to P 3 , or P 4 to P 5 is used. This is because each range is a capacitive domain in which the impedance reduces with an increase in frequency, so that characteristics are similar to one another.
[0131] For example, an element having a clock cycle of a range of P 1 to P 2 or P 3 to P 4 may be used. This is because each range is an inductive domain in which the impedance increases with an increase in frequency, so that characteristics are similar to one another. However, it is impossible to use an element having a frequency close to the peak such as P 1 , P 2 , P 3 , P 4 , P 5 , or P 6 (particularly, a frequency in a domain slightly lower than P 2 or P 4 ). This is because the dependence of the impedance on the frequency is significant in the domain.
[0132] As is apparent from FIG. 5 , the resonance point is shifted to a higher frequency domain (toward a higher frequency direction) with changing from V 1 G 1 - 1 to V 1 G 1 - 5 . For example, a first resonance point in V 1 G 1 - 5 is Q 1 . The resonance point Q 1 corresponds to the resonance point P 1 in V 1 G 1 - 1 .
[0133] In addition, a second resonance point in V 1 G 1 - 5 is Q 2 . The resonance point Q 2 corresponds to the resonance point P 2 in V 1 G 1 - 1 . Therefore, a band of about 400 MHz is ensured up to the first resonance point Q 1 . A band of a frequency which exceeds 400 MHz (about 410 MHz to about 820 MHz) is ensured in a domain from the first resonance point Q 1 to the next resonance point Q 2 .
[0134] FIG. 6 and FIG. 7 show reference characteristics in the case where the number of BC layers 6 is changed. These reference characteristics are used to check characteristics caused due to changes in the number of BC layers 6 . Therefore, as compared with the case of FIG. 5 , an analytical condition is not identical and a resonance frequency is different.
[0135] FIG. 6 shows two impedance characteristics indicated by character strings “single layer” and “two layers”. The “two layers” indicates an analytical result of an impedance characteristic in the case of the structure in Embodiment 1 ( FIG. 3 ).
[0136] On the other hand, the “single layer” indicates an impedance characteristic in the case where one of the BC layers 6 is removed from the structure in Embodiment 1. In this case, the power supply via 7 B for connecting between the power supply layers 3 - 1 and 3 - 2 and the ground via 8 for connecting between the ground layers 5 - 1 and 5 - 2 do not exist.
[0137] As shown in FIG. 6 , in the case of the single layer, a first resonance point R 1 occurs at about 200 MHz and a second resonance point R 2 occurs at about 1500 MHz. On the other hand, in the case of the two layers, a first resonance point P 1 occurs at about 150 MHz and the second resonance point P 2 occurs at about 700 MHz.
[0138] As is apparent from FIG. 6 , a capacitive impedance characteristic in the case of the two BC layers 6 reduces in a low frequency domain (about 50 MHz to about 150 MHz in FIG. 6 ) as compared with the case of the single BC layer. This indicates an increase in capacitance of each of the BC layers 6 serving as capacitors because the two power supply layers 3 are connected with each other through the power supply via 7 B and the two ground layers 5 are connected with each other through the ground via 8 .
[0139] In FIG. 6 , the impedance characteristic in the case of the two BC layers 6 appears to increase in an inductance band which exceeds 200 MHz (vicinity of the resonance point R 1 in the case of the single layer) as compared with the case of the single layer. This is because an apparent impedance in the case of the single layer is reduced by the presence of the resonance point R 1 in the case of the single layer. Therefore, in a domain sufficiently apart from the resonance point R 1 to a high frequency side, an inductive impedance in the case of the two layers is substantially equal to that in the case of the single layer.
[0140] On the other hand, as shown in FIG. 6 , a band up to the resonance point in the case of the two layers is narrower than that in the case of the single layer. For example, the resonance point P 1 in the case of the two layers is closer to a low frequency side than the resonance point R 1 in the case of the single layer.
[0141] FIG. 7 shows a comparative result between the case of the single layer, the case of the two layers, and the case of four layers, for the purpose of reference. The “four layers” shows an analytical result in the case where the four BC layers 6 are used. Note that an analytical condition in FIG. 7 is different from that related to the analytical result in the case of FIG. 6 , so that a resonance frequency is different from that in the case of FIG. 6 . Therefore, absolute frequency comparison cannot be made between FIG. 6 and FIG. 7 .
[0142] As shown in FIG. 7 , in the case of the four layers, a first resonance point T 1 occurs at about 60 MHz and a second resonance point T 2 occurs at about 120 MHz. In the case of the two layers, the first resonance point P 1 occurs at about 110 MHz and the second resonance point P 2 occurs at about 200 MHz. In the case of the single layer, the first resonance point R 1 occurs at about 190 MHz.
[0143] In the case of FIG. 7 , an impedance in a conductive domain up to each of the first resonance points (T 1 , P 1 , and R 1 ) reduces as the number of layers increases as in the case of FIG. 6 . This indicates an increase in capacitance of a capacitor by parallel connection of the BC layers 6 .
[0144] A band width up to the resonance point (for example, a band up to each of the first resonance points T 1 , P 1 , and R 1 ) becomes narrower as the number of layers increases. This is possibly because a new resonance mode is caused by the parallel connection of the BC layers 6 .
[0145] As described above, according to the structure in this embodiment, the plurality of power supply layers 3 are connected with each other through the power supply via 7 B and the plurality of ground layers 5 are connected with each other through the ground via 8 . Therefore, it is possible to increase a capacitance of each of the BC layers 6 serving as capacitors.
[0146] In this case, the band up to each of the resonance points becomes narrower as the number of layers increases. However, as shown in FIG. 5 , when the number of power supply vias 7 B and the number of ground vias 8 increase, each of the resonance points can be shifted to the high frequency side. That is, according to the multilayer printed board in this embodiment, when the plurality of BC layers 6 are connected with each other, it is possible to reduce the low frequency side impedance. Further, when the number of vias increases, the resonance point can be shifted to the high frequency domain to widen a band width.
Embodiment 2
[0147] FIG. 8 and FIG. 9 show Embodiment 2. In Embodiment 1, the number of power supply vias 7 B is made equal to the number of ground vias 8 . They are increased from one set (V 1 G 1 - 1 ) to five sets (V 1 G 1 - 5 ) by one and the impedance characteristic of the BC layers 6 are calculated. In Embodiment 2, a ratio between the number of power supply vias 7 B and the number of ground vias 8 is set to 1:2. Such a combination is increased from one set to four sets and the impedance characteristic of the BC layers 6 are calculated. Other structures are identical to those in Embodiment 1.
[0148] FIG. 8 shows the position of the power supply pin of the LSI 1 (power supply via 7 A) and the positions of the power supply vias 7 B and the ground vias 8 in this embodiment. As shown in FIG. 8 , even in any of V 1 G 2 - 1 to V 1 G 2 - 4 , a pair of ground vias 8 are provided on both sides of each of the power supply vias 7 to make one set.
[0149] In the case of V 1 G 2 - 1 , the one set is provided on the left side of the power supply pin of the LSI 1 . In the case of V 1 G 2 - 2 , the one set is further provided on the right side of the power supply pin of the LSI 1 as compared with the case of V 1 G 2 - 1 . In the case of V 1 G 2 - 3 , the one set is further provided on the upper side of the power supply pin of the LSI 1 as compared with the case of V 1 G 2 - 2 . In the case of V 1 G 2 - 4 , the one set is further provided on the lower side of the power supply pin of the LSI 1 as compared with the case of V 1 G 2 - 3 .
[0150] FIG. 9 shows a frequency characteristic of an impedance of the BC layers 6 . Even in FIG. 9 , the characteristic of the impedance of the BC layers 6 is similar to that shown in FIG. 5 . That is, as is apparent from the cases V 1 G 2 - 1 to V 1 G 2 - 4 , when the number of sets of the power supply via 7 B and the ground via 9 increases, the resonance point is shifted to the high frequency domain to widen the band width.
Embodiment 3
[0151] FIG. 10 and FIG. 11 show Embodiment 3. In Embodiment 1, the number of power supply vias 7 B is made equal to the number of ground vias 8 . They are increased from one set (V 1 G 1 - 1 ) to five sets (V 1 G 1 - 5 ) by one and the impedance characteristic of the BC layers 6 are calculated. In Embodiment 2, the ratio between the number of power supply vias 7 B and the number of ground vias 8 is set to 1:2 and the same analysis is performed.
[0152] In Embodiment 3, the ratio between the number of power supply vias 7 B and the number of ground vias 8 is set to 1:3. Such a combination is increased from one set to four sets and the impedance characteristic of the BC layers 6 are calculated. Other structures are identical to those in Embodiment 1 or 2.
[0153] FIG. 10 shows the position of the power supply pin of the LSI 1 (power supply via 7 A) and the positions of the power supply vias 7 B and the ground vias 8 in this embodiment. As shown in FIG. 10 , even in any of V 1 G 3 - 1 to V 1 G 3 - 4 , the ground vias 8 are provided on three sides of each of the power supply vias 7 B to make one set. In this case, a set in which the ground vias 8 are provided on the left, right, and lower sides of the power supply via 7 B is referred to as a type 1 . A set in which the ground vias 8 are provided on the left, right, and upper sides of the power supply via 7 B is referred to as a type 2 .
[0154] In the case of V 1 G 3 - 1 , the set of the type 1 is provided on the left side of the power supply pin of the LSI 1 . In the case of V 1 G 3 - 2 , the set of the type 2 is further provided on the right side of the power supply pin of the LSI 1 as compared with the case of V 1 G 3 - 1 . In the case of V 1 G 3 - 3 , the set of the type 2 is further provided on the upper side of the power supply pin of the LSI 1 as compared with the case of V 1 G 3 - 2 . In the case of V 1 G 3 - 4 , the set of the type 1 is further provided on the lower side of the power supply pin of the LSI 1 as compared with the case of V 1 G 3 - 3 .
[0155] FIG. 11 shows a frequency characteristic of an impedance of the BC layers 6 . Even in FIG. 11 , the characteristic of the impedance of the BC layers 6 is similar to that shown in FIG. 5 or FIG. 9 . That is, as is apparent from the cases of V 1 G 3 - 1 to V 1 G 3 - 4 , when the number of sets of the power supply via 7 B and the ground via 9 increases, the band width widens.
[0000] <Modified Example>
[0156] In the first embodiment mode, as shown in FIG. 1 or FIG. 2 , each of the BC layers is composed of the power supply layer 3 , the thin film dielectric 4 , and the ground layer 5 . The multilayer printed board is constructed based on this order (for example, the order in which the power supply layer 3 , the thin film dielectric 4 , and the ground layer 5 are provided as viewed from the printed board (multiple layers) 2 - 1 in FIG. 2 ).
[0157] However, the embodiment of the present invention is not limited to such a structure. For example, a positional relationship between the power supply layer 3 and the ground layer 5 may be arbitrarily changed in the BC layer 6 .
[0158] FIG. 12 and FIG. 13 show an example of such a multilayer printed board. FIG. 12 is a perspective view showing a modified example of the multilayer printed board according to the first embodiment mode. FIG. 13 is a front view showing the multilayer printed board viewed from a direction indicated by an arrow C in FIG. 12 .
[0159] In this example, the multilayer printed board includes two BC boards 6 A and 6 B. The BC board 6 A has the power supply layer 3 , the thin film dielectric 4 , and the ground layer 5 which are provided in this order as viewed from the printed board (multiple layers) 2 - 1 . The BC board 6 B has the ground layer 5 , the thin film dielectric 4 , and the power supply layer 3 which are provided in this order as viewed from the printed board (multiple layers) 2 - 1 . With respect to the plurality of BC layers 6 A and 6 B, the power supply layers 3 are connected with each other through the power supply via 7 B and the ground layers 8 are connected with each other through the ground via 8 . Even when the BC layers 6 A and 6 B are constructed as described above, an analytical result is identical to the results shown in FIGS. 5 to 7 , 9 , and 11 .
[0160] Even when the multilayer printed board includes over two BC layers 6 , the order in which the power supply layer 3 and the ground layer 5 are provided in the BC layer 6 is not limited. That is, even in an arbitrary combination of the BC layers 6 A and 6 B as shown in FIG. 12 , the impedance characteristic is not significantly different from that in the case where a plurality of any one of the BC layer 6 A and 6 B are combined as in the first embodiment mode.
[0161] In the first embodiment mode, the BC layers 6 and other layers such as the printed boards 2 - 1 and 2 - 2 are formed in substantially the same shape. However, the embodiment of the present invention is not limited to the same shape.
[0162] FIG. 48 shows a modified example of the multilayer printed board according to this embodiment mode in the case where it is viewed from the upper side (for example, in the direction indicated by the arrow B in FIG. 3 ). As shown in FIG. 48 , a size of the BC layer 6 may be smaller than sizes of the other printed boards. That is, a metallic coating portion 3 A of the power supply layer 3 may be formed in a portion of a board composing the power supply layer 3 and a metallic coating portion 5 A of the ground layer may be formed in a portion of a board composing the ground layer 5 . This applies to the case where the BC layer is provided only in the vicinity of the specific LSI 1 . Therefore, even when a portion of the multilayer printed board composes the BC layer 6 , the present invention can be implemented.
[0163] That is, the plurality of power supply layers 3 included in the multilayer printed board may be connected with each other through the power supply via 7 B. The plurality of ground layers 5 included in the multilayer printed board may be connected with each other through the ground via 8 .
Second Embodiment Mode
[0164] Hereinafter a multilayer printed board according to a second embodiment mode of the present invention will be described with reference to FIG. 14 to FIG. 35 . The first embodiment mode shows the impedance characteristic of the multilayer printed board in which the power supply layers 3 included in the plurality of BC layers 6 are connected with each other through the power supply via 7 ( 7 B) and the ground layers 5 included in the plurality of BC layers 6 are connected with each other through the ground via 8 .
[0165] Meanwhile, this embodiment mode shows an example of a multilayer printed board in which a power supply pin for supplying power to an element is provided near the central axis of the BC layer 6 to improve an impedance characteristic. Other structures and operations are identical to those in the first embodiment mode. Therefore, the same symbols are provided to the same constituent elements and their descriptions are omitted here.
[0000] <Structure>
[0166] FIG. 14 and FIG. 15 show an outside of the multilayer printed board according to the second embodiment mode of the present invention. FIG. 14 is a perspective view showing the multilayer printed board. FIG. 15 is a plan view showing the multilayer printed board in the case where it is viewed from a direction indicated by an arrow D in FIG. 14 .
[0167] As shown in FIG. 14 , the multilayer printed board is a multilayer printed board which includes the printed boards (multiple layers including a signal layer) 2 - 1 , 2 - 2 , and 2 - 3 and the BC layers 6 and a position in which the LSI 1 is mounted is devised. Here, it is desirable that the LSI 1 be an element to or from which a signal driven at highest speed is inputted or outputted on the multilayer printed board.
[0168] As shown in FIG. 14 , the number of signal layers is not particularly limited in the multilayer printed board. That is, the number of signal layers may be one or plural.
[0169] In FIG. 14 , the multilayer printed board includes the two BC layers 6 . However, in the embodiment of the present invention, the number of BC layers 6 may be one. As in the first embodiment, the two or more BC layers 6 may be provided, the power supply layers 3 of the respective BC layers may be connected with each other through the power supply via, and the ground layers 5 may be connected with each other through the ground via.
[0170] As shown in FIG. 15 , the feature of the multilayer printed board according to this embodiment mode is to locate power supply pins 17 of the LSI 1 substantially at the center of the BC layer 6 of the multilayer printed board. According to such location, the power supply vias connected with the power supply pins 17 can be formed near the central axis passing through the substantially center of the BC layer 6 . In the example shown in FIG. 15 , ground pins 18 are located adjacent to the power supply pins 17 .
[0171] Note that in the multilayer print shown in FIG. 14 , the respective printed boards (multiple layers 2 - 1 , 2 - 2 , and 2 - 3 and the BC layers 6 ) have substantially the same size (rectangle of 50 mm square) in the plan view as viewed from the direction indicated by the arrow D in FIG. 14 .
[0000] <Natural Resonance Frequency of Board>
[0172] FIG. 16 is an explanatory view of a natural resonance frequency of a printed board. FIG. 16 shows a natural resonance frequency of a rectangular copper sheet to a high frequency signal. Here, the copper sheet is indicated by a rectangular sheet 9 of a size of a (meters)×b (meters). Assume that a dielectric having a dielectric constant er exists around the rectangular sheet 9 made of copper. At this time, it is experimentally known that the natural resonance frequency can be expressed by formula 1 .
[0173] In the formula 1 , C 0 denotes the speed of light in a vacuum. In the formula 1 , m and n each denote an integer equal to or larger than 0 (at least one is equal to or larger than 1) and are determined according to a resonance mode.
[0174] For example, when the dielectric constant er=3.12, a=0.05 (meters), and b=0.05 (meters), a first resonance frequency fc (in the case of m=1 and n=0) is calculated to be 1.69 GHz.
[0175] This embodiment mode shows that the power supply pins 17 of the LSI 1 and the power supply vias 7 can be located near the center of the BC layer 6 to suppress such resonance.
[0176] It is expected that the resonance occurs in the case where the ½-wavelength of a high frequency signal is substantially equal to, for example, the length “a” (in the case of m=1). In addition, it is expected that the resonance occurs in the case where the ½-wavelength of the high frequency signal is substantially equal to, for example, the length “b” (in the case of n=1). Note that there is a resonance mode which cannot be determined by the experimental formula 1 shown in FIG. 16 in an actual printed board.
[0177] In the multilayer printed board, the power supply pins 17 of the LSI 1 and the power supply vias 7 are located at the central position of the BC layer 6 (on the central axis of a thin copper plate for forming the power supply layer 3 and the ground layer 5 (on an axial direction perpendicular to the thin copperplate)). According to such location, a distance between a signal generation position of the BC layer 6 (position of the power supply via connected with the power supply pin 17 on the BC layer 6 ) and each end portion of the BC layer 6 (both sides of the rectangular thin copper plate for forming the power supply layer 3 ) becomes shorter. Therefore, the distance between the signal generation position and each end portion of the BC layer 6 does not become equal to the ½-wavelength of the high frequency signal. Thus, the natural resonance in the BC layer 6 is suppressed.
[0178] In an actual design, the power supply pins 17 of the LSI 1 and the power supply vias connected therewith cannot be located near the accurate central axis of the BC layer 6 in some case. In such a case, the degree of suppression to the natural resonance is changed according to a deviation from the accurate central position. As described in the following embodiment, a radiation electric field intensity caused by the resonance increases as the power supply via is located near to one of the end portions of the BC layer 6 . Note that an effect in which a radiation electric field strength is reduced by about 10 dB as compared with a worst value is obtained in a range of 20% of a distance off from the center, between the center of the BC layer 6 and the end portion of the rectangular thin copper plate.
Embodiment 4: Result Obtained by Impedance Measurement
[0179] FIG. 17 and FIG. 18 show Embodiment 4 of the present invention. A multilayer printed board is a square in which a flat size of each layer is 50 mm×50 mm. The multilayer printed board includes a single BC layer. The BC layer is composed of a power supply layer, a thin film dielectric, and a ground layer. A thickness of the thin film dielectric is 25 microns as in the first embodiment mode. Each of layers located above and below the BC layer has an insulator having a thickness of 40 microns.
[0180] FIG. 17 shows a shape of the printed board 2 - 1 (or the BC layer 6 ) in the case where the multilayer printed board is viewed from the direction indicated by the arrow D in FIG. 14 . TH 3 indicates a through hole passing through the vicinity of the central position of the BC layer 6 . An axis which corresponds to the through hole and is perpendicular to a paper surface is referred to as the central axis of the BC layer 6 .
[0181] Similarly, TH 1 indicates a through hole passing through the vicinity of a vertex of the rectangular BC layer 6 . Similarly, TH 2 indicates a through hole passing through the vicinity of the center of a square side composing the BC layer 6 . As described in the first embodiment mode, a power supply via is formed in each of the through holes. Each power supply via is connected with the power supply layer 3 . An outer diameter of the power supply via in this embodiment is 0.3 mm equal to that in the first embodiment mode.
[0182] As shown in FIG. 17 , in this embodiment mode, the power supply pins of the LSI 1 are located at the positions of TH 1 to TH 3 and connected with the vias located at the respective positions to produce three kinds of multilayer printed boards. In each of the multilayer printed boards, the impedance between the power supply layer 3 and the ground layer 5 is measured.
[0183] In the measurement, a black box is assumed between the power supply layer 3 and the ground layer 5 which compose the BC layer 6 . AS (scattering) parameter is obtained using a network analyzer. The impedance between the power supply layer 3 and the ground layer 5 is obtained from the value of the S parameter. Note that a matrix representation of the S parameter is called a S matrix. A procedure for obtaining the impedance of the black box from the S matrix is known.
[0184] As shown in the abscissa of each of graphs G 1 to G 3 , a frequency is changed from the vicinity of 0 Hz to the vicinity of 10 GHz to measure the impedance. In the graphs G 1 to G 3 , peaks and valleys (for example 100 and 101 in G 1 ) each indicate a resonance point.
[0185] As is apparent from G 3 shown in FIG. 17 , when the power supply pin 17 of the LSI 1 is located in TH 3 , peaks 100 to 103 present in G 1 disappear. This may be because a distance between the position of the TH 3 and an outer edge of the BC layer 6 (thin copper plate of the power supply layer 3 ) is shorter than the ½-wavelength of the high frequency wave. That is, although the high frequency wave is injected from the via formed at the position of the TH 3 to the BC layer 6 , the resonance caused thereby is suppressed.
[0186] As is apparent from a result obtained by measurement in G 2 , the peaks 102 and 103 present in G 1 disappear. This may be because a distance between the position of the TH 2 and each of sides (sides 50 and 51 ) of the BC layer 6 (thin copper plate of the power supply layer 3 ) is shorter than the ½-wavelength of the high frequency wave at the resonance frequency. On the other hand, the peaks 100 and 101 present in G 1 do not disappear even in the result obtained by measurement in G 2 (they are present as peaks 100 A and 101 A). This may be because a distance between the position of the TH 2 and an opposite side (side 52 ) of the BC layer 6 (thin copper plate of the power supply layer 3 ) is close to the ½-wavelength of the high frequency wave at the resonance frequency.
[0187] FIG. 18 shows the superposition of results of G 1 to G 3 obtained by measurement as shown in FIG. 17 . As shown in FIG. 18 , a resonance characteristic of the peak 100 A in the result G 2 becomes weaker than that of the peak 100 in the result G 1 . Note that each of frequencies of the peaks is substantially equal to a result obtained by calculation based on the formula 1 and is about 1690 MHz. In the result of G 3 , as indicated by reference 100 B, the peak in the vicinity of 1.69 GHz disappears.
[0000] <Analytical Result of Current Distribution>
[0188] FIGS. 19 to 24 show analytical results of a high frequency current distribution in the vicinity of the resonance frequency in each of the cases where the power supply pin 17 of the LSI 1 is located in TH 1 to TH 3 . In this analysis, it is assumed to leak a high frequency signal from the power supply pin 17 and a current distribution in each of the cases where a high frequency voltage is supplied from the positions of TH 1 to TH 3 is obtained.
[0189] FIG. 49 shows an analytical model of the multilayer printed board according to this embodiment mode. As shown in FIG. 49 , the analytical model includes a thin film dielectric 2 A, the power supply layer 3 , a thin film dielectric 2 B, the ground layer 5 , and a thin film dielectric 2 C. The thin film dielectrics 2 A, 2 B, and 2 C have 40 microns, 25 microns, and 40 microns in thickness, respectively. Each of the thin film dielectrics 2 A, 2 B, and 2 C has a dielectric constant Er of 3.12.
[0190] In this model, a wave source (high frequency power supply) is set between the power supply layer 3 and the ground layer 5 . The wave source is connected with the power supply layer 3 and the ground layer 5 through the via. The wave source is originally necessarily set to the power supply via that connects the power supply pin of the LIS mounted on the multilayer printed board with the power supply layer. However, as in the first embodiment mode, the wave source is set to the above-mentioned position for simplification of the model. In order to fit the simplified model to a measured value, a parasitic inductor is set to the power supply via.
[0191] As in the first embodiment mode, a high frequency power supply signal has a trapezoid waveform whose rise time and fall time each are 500 ps, period is 100 MHz, and amplitude is 3.3 volts.
[0192] Even in the analysis, the electromagnetic analysis program based on the piecewise sinusoidal moment method is used as in the first embodiment mode. Hereinafter, FIG. 19 to FIG. 21 show current distributions at a frequency of 1600 MHz, each of which corresponds to the vicinity of the peak 100 shown in FIG. 18 .
[0193] FIG. 19 shows an analytical result of a current distribution in a direction indicated by an arrow E in the case where the power supply pin 17 is located in TH 1 shown in FIG. 17 . In the analysis, the wave source is set just below TH 1 and between the power supply layer 3 and the ground layer 5 (see FIG. 49 ). As shown in FIG. 19 , a current in the direction indicated by the arrow E produces a distribution having a mountain shape with respect to the side 51 of the BC layer 6 . A peak of the mountain shape corresponds to a current density of about 0.1 A/m.
[0194] FIG. 20 shows an analytical result of a current distribution in the direction indicated by the arrow E in the case where the power supply pin 17 (power supply via 7 ) is located in TH 2 shown in FIG. 17 . In the analysis, the wave source is set just below. TH 2 and between the power supply layer 3 and the ground layer 5 (see FIG. 49 ). As shown in FIG. 20 , even in this case, a current in the direction indicated by the arrow E produces a distribution having a mountain shape with respect to the side 51 of the BC layer 6 . A peak of the mountain shape corresponds to a current density of about 0.15 A/m.
[0195] FIG. 21 shows an analytical result of a current distribution in the direction indicated by the arrow E in the case where the power supply pin 17 (power supply via 7 ) is located in TH 3 shown in FIG. 17 . In the analysis, the wave source is set just below TH 3 and between the power supply layer 3 and the ground layer 5 (see FIG. 49 ). As shown in FIG. 21 , in this case, a current in the direction indicated by the arrow E is locally produced in the vicinity of the position of the power supply pin 17 of the LSI 1 . A peak of the current at a narrowly limited area close to the position of the power supply pin 17 corresponds to about 0.75 A/m.
[0196] Hereinafter, FIG. 22 to FIG. 24 show current distributions at a frequency of 2330 MHz, each of which corresponds to the vicinity of the peak 101 shown in FIG. 18 . FIG. 22 shows an analytical result of a current distribution in a direction indicated by an arrow F in the case where the power supply pin 17 is located in TH 1 shown in FIG. 17 . As shown in FIG. 22 , a current in the direction indicated by the arrow F produces a mountain-shaped distribution having a saddle portion. The reason why the saddle portion is formed may be that the resonance mode is different from that in the case of FIG. 19 . In FIG. 22 , a peak of the mountain shape corresponds to a current density of about 0.3 A/m.
[0197] FIG. 23 shows an analytical result of a current distribution in the direction indicated by the arrow F in the case where the power supply pin 17 is located in TH 2 shown in FIG. 17 . As shown in FIG. 23 , in this case, a current in the direction indicated by the arrow F is locally produced in the vicinity of the position of the power supply pin 17 of the LSI 1 . A peak of the current at a narrowly limited area close to the position of the power supply pin 17 corresponds to about 0.75 A/m. This is because a distance between a voltage supply point and the side 50 or 51 in the direction indicated by the arrow F is not equal to an integral multiple of a half wavelength of the high frequency wave at the resonance frequency (2.333 GHz).
[0198] FIG. 24 shows an analytical result of a current distribution in the direction indicated by the arrow F in the case where the power supply pin 17 is located in TH 3 shown in FIG. 17 . The analytical result shown in FIG. 24 is substantially identical to that in the case of FIG. 21 .
[0000] <Analytical Result of Radiation Electric Field Strength>
[0199] FIG. 25 to FIG. 35 show analytical results of a radiation electric field strength caused by an electromagnetic wave from the multilayer printed board. In the analysis, the electromagnetic wave emitted from the model of the multilayer printed board as shown in FIG. 49 is analyzed at each of positions shown in FIG. 50 to obtain a maximal value of the electric field strength among values got in the analyzed points. The reason why the maximal value of the electric field strength is obtained is to obtain an electric field strength at a position in which a directivity of a radiation pattern formed by the multilayer printed board becomes maximal.
[0200] According to the analysis, when current distributions of the model of the multilayer printed board as shown in FIG. 49 are obtained, electric field strengths can be obtained by solving Maxwell equations with respect to the respective current distributions. This becomes, for example, the superposition of radiation electric fields caused by respective currents obtained on a mesh as shown in FIG. 25 .
[0201] FIG. 50 shows observation points of the radiation electric field strength. As shown in FIG. 50 , a cylindrical coordinates system is used and the multilayer printed board is located at the center of the cylinder. At this time, the central axis (z-axis) of the cylinder is aligned with a normal line passing through the center of the multilayer printed board. Divisional lines parallel to the z-axis are set by which a cylindrical surface distanced from the central axis by a radius of 1.5 m is divided into 72 segments in a circumferential direction.
[0202] Divisional lines in the circumferential direction are set by which the cylindrical surface is divided into 6 segments within an area of 3 m in a Z-direction. Positions of the divisional lines in the circumferential direction correspond to Z=1.5 m, 0.9 m, 0.3 m, −0.3 m. −0.9 m, and −1.5 m. In this case, the central position of the multilayer printed board in the Z-direction (position of Z 0 shown in FIG. 49 ) is set to Z=0 in the cylindrical coordinates. Intersections of the divisional lines parallel to the z-axis and the divisional lines in the circumferential direction are set to the observation points. When the electric filed strength is measured, an antenna for measuring vertical polarization and horizontal polarization may be set in the observation points.
[0203] FIG. 25 shows a relationship between the central position of the BC layer 6 and the position of the power supply via 7 connected with the power supply pin 17 of the LSI 1 (position in which the wave source is projected when being projected to the BC layer 6 ). In FIG. 25 , the BC layer 6 is specified using references 6 A to 6 G based on the position of the power supply via 7 .
[0204] The drawing of the BC layer 6 A shows the case where the power supply via 7 is located at a center 110 of the BC layer. In any cases ( 6 A to 6 G), assume that a flat surface of the BC layer is a square whose side length is 50 mm.
[0205] The drawing of the BC layer 6 B shows the case where the power supply via 7 is shifted from the center 110 of the BC layer by 3.85 mm. In this case, according to expression using a relative amount in which positions of the four sides of the rectangle are set as 100%, the degree of shift of the power supply via 7 from the center 110 is 3.85/25=15.4%. In FIG. 25 , a shift direction is a direction from the center of the BC layer to the center of a side of a rectangular region.
[0206] The drawing of the BC layer 6 C shows the case where the power supply via 7 is shifted from the center 110 of the BC layer by 7.7 mm. In this case, according to the expression using the relative amount in which the positions of the four sides of the rectangle are set as 100%, the degree of shift of the power supply via 7 from the center 110 is 7.7/25=30.8%.
[0207] The drawing of the BC layer 6 D shows the case where the power supply via 7 is shifted from the center 110 of the BC layer by 11.6 mm. In this case, according to the expression using the relative amount in which the positions of the four sides of the rectangle are set as 100%, the degree of shift of the power supply via 7 from the center 110 is 11.6/25=46.4%.
[0208] The drawing of the BC layer 6 E shows the case where the power supply via 7 is shifted from the center 110 of the BC layer by 15.4 mm. In this case, according to the expression using the relative amount in which the positions of the four sides of the rectangle are set as 100%, the degree of shift of the power supply via 7 from the center 110 is 15.4/25=61.6%.
[0209] The drawing of the BC layer 6 F shows the case where the power supply via 7 is shifted from the center 110 of the BC layer by 19.3 mm. In this case, according to the expression using the relative amount in which the positions of the four sides of the rectangle are set as 100%, the degree of shift of the power supply via 7 from the center 110 is 19.3/25=77.2%.
[0210] The drawing of the BC layer 6 G shows the case where the power supply via 7 is shifted from the center 110 of the BC layer by 23.1 mm. In this case, according to the expression using the relative amount in which the positions of the four sides of the rectangle are set as 100%, the degree of shift of the power supply via 7 from the center 110 is 23.1/25=92.4%.
[0211] FIG. 26 and FIG. 27 show analytical results of the radiation electric field strength in the cases where the position of the power supply via 7 is changed (wave source shown in FIG. 49 ).
[0212] FIG. 26 is a plot showing a radiation electric field strength (horizontal polarization component) according to a positional relationship between the central position 110 and the power supply via 7 in the BC layer 6 based on a frequency. In FIG. 26 , the positional relationship between the central position 110 and the power supply via 7 of the LSI 1 is expressed at a ratio thereof to a size of the entire BC layer. Here, when the power supply via 7 is on a side of the rectangle formed by the BC layer 6 (conductor composing the power supply layer and the ground layer), the ratio is 100%.
[0213] The ordinate in FIG. 26 indicates the radiation electric field strength of horizontal polarization in the case where a high frequency signal in each positional relationship is supplied to the power supply via 7 (wave source shown in FIG. 49 ) and its unit is dBμV/m. As described above, a signal from a high frequency power source set as the wave source has a trapezoid waveform whose rise time and fall time each are 500 ps, period is 100 MHz, and amplitude is 3.3 volts.
[0214] As shown in FIG. 26 , in any positional relationship, the radiation electric field strength becomes maximal at a frequency of the vicinity of the 1690 MHz. Therefore, this is identical to the results ( FIG. 17 and FIG. 18 ) or the analytical results ( FIG. 19 to FIG. 24 ) as described earlier.
[0215] The horizontal polarization is very weak in the case where the power supply via 7 (power supply pin 17 of the LSI 1 ) is located at the center 110 of the BC layer.
[0216] On the other hand, the radiation electric field strength increases as the power supply via 7 (power supply pin 17 of the LSI 1 ) is shifted to a peripheral portion. Note that the electric field strength in the case of separation of 20% or less is reduced by substantially 10 dB or more as compared with the case of separation of 90% or more between the central position 110 and the peripheral portion.
[0217] FIG. 27 shows an analytical result of a vertical polarization component under the same condition as that in the case of FIG. 26 . As is apparent from FIG. 27 , even in the vertical polarization, the radiation electric field strength becomes maximal at a frequency of the vicinity of the 1690 MHz.
[0218] Even when the power supply via 7 (power supply pin 17 of the LSI 1 ) is located at the center 110 of the BC layer, the vertical polarization becomes larger than the horizontal polarization.
[0219] Even in the case of the vertical polarization, the radiation electric field strength further increases as a projection position 17 A of the power supply pin 17 of the LSI 1 is shifted to a peripheral portion. Note that the electric field strength in the case of separation of 20% or less is also reduced by substantially 10 dB or more as compared with the case of separation of 90% or more between the central position 110 and the peripheral portion.
[0220] FIG. 28 shows respective states ( 6 H to 6 L) of the BC layer 6 in the cases where the power supply via 7 (power supply pin 17 of the LSI 1 ) is shifted from the central position in the vertex direction of the rectangle formed by the BC layer.
[0221] FIG. 29 shows a result obtained by analysis of the horizontal polarization of the radiation electric field strength in the case where the positional relationship is changed as shown in FIG. 28 . Even in the case of the shift in the vertex direction as shown in FIG. 28 , the same result as that shown in FIG. 26 is exhibited with respect to the horizontal polarization. Note that a position of 100% in FIG. 29 corresponds to a vertex position (each of four corner ends) of the rectangle formed by the BC layer as shown in FIG. 28 .
[0222] FIG. 30 shows a result obtained by analysis of the vertical polarization of a radiation electric field strength in the case where the positional relationship is changed as shown in FIG. 28 . Even in the case of the shift in the vertex direction as shown in FIG. 28 , the same result as that shown in FIG. 27 is exhibited with respect to the vertical polarization.
[0223] FIGS. 31 to 35 show results obtained by the same analysis as that shown in FIG. 25 to FIG. 30 with respect to the multilayer board including the BC layer 6 having a rectangular shape of 25 mm square. FIG. 31 shows a position of the power supply via 7 connected with the power supply pin 17 of the LSI 1 (wave source is set between the power supply layer and the ground layer). FIG. 32 shows an analytical result of horizontal polarization in the case where the power supply via 7 is shifted from the center 110 of the BC layer to the center of a side of the rectangle. FIG. 33 shows an analytical result of vertical polarization in such a case.
[0224] FIG. 34 shows an analytical result of horizontal polarization in the case where the power supply via 7 (and the wave source located just thereunder) is shifted from the center 110 of the BC layer in the vertex direction of the rectangle. FIG. 35 shows an analytical result of vertical polarization in such a case.
[0225] According to the formula 1 shown in FIG. 16 , the natural resonance frequency of the square of 25 mm is twice that of a square of 50 mm and thus becomes 3.38 GHz. As shown in FIGS. 32 to 35 , the electric field strength becomes maximal in the vicinity of the natural resonance frequency in any cases. In any cases, the radiation electric field strength increases as the power supply via 7 is shifted to the peripheral portion. Note that the electric field strength in the case of separation of 20% or less is also reduced by substantially 10 dB or more as compared with the case of separation of 90% or more between the central position 110 and the peripheral portion.
[0226] As described above, when the power supply pin 17 of the LSI 1 (element having a highest operating frequency is desirable) on the signal layer in the multilayer printed board is located such that a projection position onto the BC layer 6 is close to the center of the BC layer 6 , the natural resonance can be reduced. For example, when the power supply pin 17 of the LSI 1 on the signal layer is vertically connected to each board through the power supply via 7 , it may be desirable that the power supply via 7 is provided close to the central portion of the BC layer.
[0227] Assume that a size of the entire board (end position of the rectangle formed from the BC layer) is 100%. At a position which is within an area of 20% from the central position 110 , the electric field strength can be reduced by 10 dB or more as compared with the case where the power supply via 7 is located in the board end portion of the BC layer 6 .
[0000] <Modified Example>
[0228] In the first embodiment mode and the second embodiment mode, the BC layer 6 and another layer such as the signal layer 2 - 1 are formed in substantially the same shape. However, the embodiment of the present invention is not limited to such a shape.
[0229] For example, as shown in FIG. 48 , the size of the BC layer 6 may be narrowed as compared with another printed board. FIG. 48 shows the modified example of the multilayer printed board according to this embodiment mode as viewed from the upper side (for example, in the direction indicated by the arrow D in FIG. 14 ).
[0230] That is, the metallic coating portion 3 A of the power supply layer 3 may be formed in a portion of the board composing the power supply layer 3 and the metallic coating portion 5 A of the ground layer 5 may be formed in a portion of the board composing the ground layer 5 . This corresponds to the case where the BC layer 6 is provided only in the vicinity of the specific LSI 1 in the multilayer printed board. Therefore, even when a portion of the multilayer printed board composes the BC layer 6 , the present invention can be embodied.
[0231] That is, the power supply via 7 of the LSI 1 may be located close to the center of the BC layer 6 with respect to the partial BC layer 6 .
Third Embodiment Mode
[0232] Hereinafter a multilayer printed board according to a third embodiment mode of the present invention will be described with reference to FIG. 36 to FIG. 47 .
[0000] <Structure>
[0233] FIG. 36 is a perspective view showing the multilayer printed board according to the third embodiment mode of the present invention.
[0234] As shown in FIG. 36 , the BC layer in the multilayer printed board according to this embodiment mode becomes a circle as compared with that shown in the first embodiment mode ( FIG. 1 and the like) or the second embodiment mode ( FIG. 14 ) (This is referred to as the circular BC layer 16 ). That is, a metallic thin film (copper thin film) composing each of a power supply layer 13 and a ground layer 15 becomes a circle.
[0235] On the other hand, other constituent elements of the multilayer printed board according to this embodiment mode are identical to those in the case of the first embodiment mode or the second embodiment mode. Therefore, the same references are provided for the same constituent elements and thus the descriptions are omitted here.
[0236] In FIG. 36 , the thin film dielectric 4 has the same shape as that shown in the first embodiment mode ( FIG. 1 and the like) or the second embodiment mode ( FIG. 12 ). Instead of such a shape, the thin film dielectric 4 may be formed in the same circular shape as that of the power supply layer 13 or the ground layer 15 .
[0237] FIG. 37 is a plan view as viewed from a direction indicated by an arrow G in FIG. 36 . As shown in FIG. 37 , in the multilayer printed board according to this embodiment mode, the power supply pin 17 of the LSI 1 is located to the position where the central axis of the BC layer 16 (power supply layer 13 and ground layer 15 ) passes through.
[0238] For example, the power supply via may be formed perpendicular to the board surface at the position of the power supply pin 17 so that the power supply via passes through the central axis of the BC layer 16 . In FIG. 37 , the ground pin 18 of the LSI 1 is located close to the power supply pin 17 .
[0239] According to such a structure, a distance between the power supply via and each of the peripheral portions of the BC layer 16 (peripheral portion of the copper thin film composing the power supply layer 13 and the peripheral portion of the copper thin film composing the ground layer 15 ) can be adjusted to an equal distance on the BC layer 16 . FIG. 38 shows comparison between the BC layer 16 and the BC layer 6 in the first embodiment mode or the second embodiment mode.
[0240] In the second embodiment mode, the BC layer is formed in the rectangular shape of 50 mm (or 25 mm) square. On the other hand, in this embodiment mode, a copper thin film having a diameter of 50 mm is used for the power supply layer 13 and the ground layer 15 in order to form the circular BC layer 16 .
[0241] FIG. 39 shows analytical results of impedance in the case where the power supply via is located close to the central axis of the BC layer which is the rectangle of 50 mm square as used in the second embodiment mode and in the case where the power supply via is located close to the central axis of the circular BC layer 16 having the diameter of 50 mm. The analytical procedure and the analytical condition are identical to those in the second embodiment mode. That is, the wave source is set between the power supply layer and the ground layer.
[0242] A graph 120 shows a frequency characteristic of an impedance between the power supply layer 3 and the ground layer 5 in the case where the power supply via (and the wave source located just thereunder) is located close to the central axis of the BC layer which is the rectangle of 50 mm square as used in the second embodiment mode. As described in the second embodiment mode, when the power supply via is located close to the center of the rectangular BC layer 6 (power supply pin 17 of the LSI 1 is located close to the central axis of the BC layer 6 on the signal layer), a natural resonance mode can be suppressed and a peak impedance value at the time of natural resonance can be reduced.
[0243] When the circular BC layer 16 in this embodiment mode is employed and the power supply via is located close to the central axis thereof, as shown in the graph 121 , the natural resonance mode can be further suppressed as compared with the case of the rectangle. For example, in the case of the graph 121 of FIG. 39 , only two resonance points are present in the vicinities of 4000 MHz and 7100 MHz.
[0244] It may be the result of reduction of combinations of resonance modes, which is brought by a distance up to the peripheral portion of the circular BC layer 16 becoming substantially equal as viewed from the center of the circular BC layer 16 .
[0000] <Modified Example>
[0245] The third embodiment mode shows that, when the circular BC layer 16 is employed and the power supply via is located close to the central axis of the circular BC layer 16 , it is possible to suppress the resonance mode. That is, the power supply pin 17 of an IC having a highest operating frequency is located close to the axis passing through the center of the circular BC layer 16 to reduce the natural resonance mode of the BC layer.
[0246] However, the embodiment of the present invention is not limited to such a structure. For example, as shown in FIG. 40 , the BC layer may be formed in a flat shape of a regular polygon other than a square, such as a regular octagon, a regular hexadecagon, or a regular triacontakaidigon.
[0247] FIG. 41 is a graph obtained by plotting a frequency characteristic of an impedance between the power supply layer and the ground layer in the BC layer having the flat shape of the square, the regular octagon, the regular hexadecagon, or the regular triacontakaidigon.
[0248] In FIG. 41 , the rectangle indicates the case where the BC layer is a rectangle of 50 mm square. The octagon, the hexadecagon, or the triacontakaidigon indicates the case where the BC layer is a regular polygon. In such a case, a length of a diagonal line of each of the regular octagon, the regular hexadecagon, and the regular triacontakaidigon is set to 50 mm.
[0249] As is apparent from FIG. 41 , the resonance in a low frequency domain is suppressed as the polygon is changed from the rectangle to the regular octagon, the regular hexadecagon, or the regular triacontakaidigon (respectively indicated by the octagon, the hexadecagon, or the triacontakaidigon in FIG. 41 ), so that the resonance position is present on the high frequency side. In FIG. 41 , the reason why the resonance position in the regular hexadecagon is present on the high frequency domain side than that in the regular triacontakaidigon may be an analytical error caused by modeling.
[0250] FIGS. 42 and 43 show analytical results of current densities in the rectangular BC layer in the vicinities of the resonance points. FIGS. 44 and 45 show analytical results of current densities in the regular octagonal BC layer and the regular triacontakaidigonal BC layer at the time of resonance. In each of those results, the same high frequency voltage as that in the second embodiment mode is supplied to obtain a current density distribution.
[0251] FIG. 42 shows a current distribution in the rectangular BC layer, which is caused by a high frequency current of 3.29 GHz. This is a current distribution in the vicinity of a resonance point present on a low frequency domain side in the rectangle shown in FIG. 41 (left side in FIG. 41 ). FIG. 43 shows a current distribution in the rectangular BC layer, which is caused by a high frequency current of 4.65 GHz. This is a current distribution in the vicinity of a resonance point present on a high frequency domain side in the rectangle shown in FIG. 41 (right side in FIG. 41 ).
[0252] FIG. 44 shows a current distribution in the octagonal BC layer, which is caused by a high frequency current of 4.65 GHz.
[0253] FIG. 45 shows a current distribution in the triacontakaidigonal BC layer, which is caused by the high frequency current of 4.65 GHz.
[0254] As is apparent from FIGS. 42 to 45 , the current densities in the regular octagonal BC layer and the regular triacontakaidigonal BC layer reduce as compared with the rectangular BC layer. Note that the case of the regular hexadecagonal BC layer is similar to the case of the regular triacontakaidigonal BC layer (not shown here).
[0255] FIG. 46 shows analytical results of radiation electric field strengths in the rectangular BC layer, the regular octagonal BC layer, the regular hexadecagonal BC layer, and the regular triacontakaidigonal BC layer at the time of resonance. The analytical condition and the measurement condition are identical to those in the second embodiment mode ( FIGS. 26, 27 , 29 , and 30 ).
[0256] As shown in FIG. 46 , in the case of the rectangular BC layer, the radiation electric field strength becomes stronger in the vicinities of resonance points (such as the vicinities of 3300 MHz and 4800 MHz). On the other hand, the radiation electric field strengths in the regular octagonal BC layer, the regular hexadecagonal BC layer, and the regular triacontakaidigonal BC layer can be suppressed as compared with that in the rectangular BC layer.
[0257] When the above-mentioned results are generalized, the flat shape of the BC layer is made such that a ratio Lmax/Lmin between maximal values Lmax and minimal values Lmin of a distance between the center of the BC layer and the peripheral portion of the BC layer becomes 1 to 1.41. Therefore, the resonance mode can be reduced to reduce the radiation electric field strength. For example, a conductor thin film composing the power supply layer and the ground layer (or at least one of those) may be formed such that the ratio Lmax/Lmin between the maximal values Lmax and minimal values Lmin of a distance between the center of the conductor thin film and the peripheral portion thereof becomes 1 to 1.41.
[0258] For example, in the case of the square, the ratio between maximal and minimal values of a distance between the center and the peripheral portion is 1.41421356. In the case of circle, the ratio between maximal and minimal values of a distance between the center and the peripheral portion is 1.
Fourth Embodiment Mode
[0259] Hereinafter, the electronic apparatus 100 according to a fourth embodiment mode of the present invention will be described with reference to the drawing of FIG. 47 . The electronic apparatus 100 is, for example, a communication apparatus such as a router or a packet switching device or an information processing apparatus such as a computer main body. The feature of the electronic apparatus 100 is to include any one of the multilayer boards (multilayer board 101 in FIG. 47 ) as described in the first embodiment mode to the third embodiment mode in its case and mount the above-mentioned element thereon.
[0260] Therefore, when the multilayer board 101 is constructed to connect between the plurality of BC layers 6 as described in the first embodiment mode, the impedance between the power supply layer 3 and the ground layer 5 in a low frequency domain (for example, up to the first resonance point) can be reduced. In such a case, when the plurality of power supply vias 7 or the plurality of ground vias 8 are provided, the resonance frequency can be shifted to the high frequency domain, with result that it is possible to widen the operating frequency band.
[0261] When the power supply pin of a high-speed (for example, the operating frequency is 1 GHz or more) element is located close to the central axis of the BC layer in the multilayer board 101 as described in the second embodiment mode, the resonance mode can be reduced to reduce the radiation electric field strength.
[0262] In the multilayer board 101 , as described in the third embodiment mode, the BC layer is formed in a shape of regular polygon having sides whose number is equal to or larger than five and the power supply pin of a highest-speed element is located close to the central axis of the BC layer. Therefore, the resonance mode can be further reduced to reduce the radiation electric field strength.
[0263] Thus, when the multilayer printed board including any of the BC layers 6 described in the first embodiment mode to the third embodiment mode is introduced into the electronic apparatus, unnecessary resonance can be prevented to ensure stable operation. In addition, it is possible to increase the degree of freedom for designing the stable electronic apparatus.
INDUSTRIAL APPLICABILITY
[0264] The present invention can be used for an industry in which a printed board is manufactured and an industry in which an electronic apparatus including the printed board is manufactured.
[0000] <<Others>>
[0265] The disclosures of international application PCT/JP2003/001010, filed on Jan. 31, 2003 including the specification, drawings and abstract are incorporated herein by reference. | A multilayer printed board comprising a plurality of capacitive coupling layers ( 6 ) each consisting of a dielectric layer ( 4 ) and a power supply layer ( 3 ) and a ground layer ( 5 ) facing each other while sandwiching the dielectric layer ( 4 ), first vias ( 7 ) connecting between the power supply layers ( 3 ) included in the plurality of capacitive coupling layers ( 6 ), and second vias ( 8 ) connecting between the ground layers ( 5 ) included in the plurality of capacitive coupling layers ( 6 ). | 7 |
FIELD OF THE INVENTION
This invention relates to scaffolding. More particularly, this invention relates to devices for securing platforms to scaffolding so that the scaffolding is structurally sound and easy to assemble, adjust, use, and dis-assemble.
BACKGROUND
In the past, many attempts have been made to design and construct scaffolding that is not only economical to manufacture but also reliable and easy to move, assemble, dis-assemble, and adjust. One problem is that, in order to make scaffolding economical and easy to assemble, dis-assemble, and adjust, the tolerances between many respective parts should be relatively loose. As a result, the assembled scaffold can be structurally weak, shaky, and unreliable. Platforms within the scaffolding and other structure can fall out of the structure during assembly, dis-assembly, and use of the scaffolding to support persons or materials. This type of design trade-off, between (a) economics and ease of assembly, movement, adjustment, and dis-assembly versus (b) structural rigidity, strength, integrity, and safety, has long been a well known and obviously serious concern in the scaffolding art.
For example, much work has been done to try to improve the mechanisms for securing the scaffolding platform to the support legs in a reliable, strong, adjustable, economical, and easily assembled and dis-assembled fashion. Examples of these efforts are shown in U.S. Pat. No, 409,167, 5,028,164, and 4,793,438. All have met with limited success.
For example, the scaffold shown in U.S. Pat. No. 409,167 has support arms at an acute angel to the platform supported by the arms with a bent arm section penetrating apertures in the support legs perpendicularly to the axis of the support legs. The support arms of this structure are thin, relatively flexible, and as a result, non-stable. The bent arm is also subject to significant bending forces that could cause the arm to bend out of position or shear, in which event the scaffold would likely collapse. In addition, the platform of this scaffold is supported only by the relatively thin and angled bent arms in cooperation with four wooden-plank support legs. The structure would not reliably support the relatively large quantities of weight that operators often seek to place on scaffolding today.
The scaffold connection shown in U.S. Pat. No. 5,028,164 has a stronger connecting mechanism for securing the platform to the legs. The legs, however, must have multiple, relatively costly cup-shaped supporting structures in any of the positions in which the platform will be secured along the axial length of the legs. The cup-shaped structures surround the entire leg. They serve as hooks for mating inverted hooks mounted in a complicated, cooperative housing, which includes a spring-loaded latch to lock the inverted hooks and housing in place on the cup-shaped supporting structures. This structure is not only relatively complicated and costly to manufacture, but also difficult, and perhaps impossible, to utilize in a scaffold in which the platform must be readily adjustable along the length of the support legs. This scaffold connection cannot slide along the surface of the legs (due to the cup-shaped hooks) to provide easy adjustment of the height of the platform. This structure also would provide a safety concern if unutilized cup-shaped hooks protrude along the axial length of the legs in areas where persons would be working on a platform supported by the legs.
The scaffold of U.S. Pat. No. 4,793,438 has a connecting mechanism that slides along the support legs and connects to a platform support beam. The support beam is slidable up and down, along with the connecting mechanism, along the support legs. The connecting mechanism has a spring-biased slidable pin that penetrates the support legs perpendicularly to the axis of the support of legs (i.e., parallel to the plane of the platform). As the scaffold is utilized, however, this slidable pin can slide horizontally out of position during assembly, dis-assembly, or use, which can create quite a dangerous situation. This slidable pin and pin housing also does not itself significantly prevent relative horizontal motion between the connecting mechanism and support legs. The pin housing does not itself provide any acute-angled structural connection and support for the central section of the platform and instead utilizes a separate beam for this purpose. In addition, even when assembled, this scaffold allows significant play or movement between the platform and support legs due to, among other things, the lose tolerance between the slidable connecting assembly and the support legs.
Applicant has utilized scaffolds of the type shown in U.S. Pat. No. 4,793,438 and, due to the significant play or movement described above, has observed the platform fall out of this type of scaffold when assembled and in use. This type of play and movement in prior art structures has long provided a significant and dangerous problem to those who use or are in the vicinity of such scaffolding.
OBJECTS OF THE INVENTION
It is therefor an object or advantage (hereinafter "object") of the present invention to provide a scaffold that is easily assembled, adjusted, dis-assembled, and moved, yet is also economical, rigid, strong, and safe.
It is another object of the present invention to provide a scaffold in which the height of the platform can be readily adjusted and secured in place during assembly, dis-assembly, or use.
It is a further object of the present invention to provide a secure yet slidable pin connection between a platform and support legs.
A still further object is to provide such a pin connection that also provides significant support for the central section of a platform with minimal structure.
Yet another object is to, when appropriate, provide lateral support members connecting multiple pin connecting assemblies to provide a more secure scaffold.
An additional object is to remove play and movement within scaffolding structures to make the scaffolding more rigid and secure during use.
A further object is to make the scaffold difficult to unintentionally dis-assemble.
Yet another object is to provide a pin connection that is easily repaired or replaced.
Another object is to provide a scaffold assembly in which the platform cannot fall down or move out of place during use of the platform.
There are other objects and advantages of the present invention. They will become apparent as the specification proceeds.
SUMMARY OF THE INVENTION
The applicant has developed an adjustable scaffold assembly that has a substantially planar support member, at least one supporting leg, and a connecting assembly that is slidable along the support leg. The support leg has apertures along its axial length, and the connecting assembly includes a slidable pin that penetrates an aperture in the leg at an acute angle to the axis of the support leg. In this manner, the connecting assembly can be, among other things, securely connected to the support legs and the connecting assembly, and the support legs securely support the platform.
There are other aspects of the invention such as, for example, a spacer between the platform and the support leg. The spacer can remove relative play or movement between the platform and the support leg, rendering the scaffold more secure.
There are other aspects of the invention that will become apparent as the specification proceeds.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the applicant's preferred scaffold, with a pin housing assembly reliably supporting the platform on the support legs;
FIG. 2 is a side elevational view of two support legs on one side of the preferred scaffold, with transverse railings rigidly interconnecting the two legs;
FIG. 3 is a sectional view of the junction of the platform, pin housing assembly, and support leg of the scaffold of FIG. 1, showing the pin housing in cross-sectional view;
FIG. 4 is a cross-sectional view of a portion of the pin housing taken along section line 4--4 of FIG. 3; and
FIG. 5 is a top elevational view of the preferred embodiment of FIG. 1 with the support rail removed and showing the spacers that force play out of the scaffold.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring to FIG. 1, the preferred embodiment of the applicant's scaffold, generally 10, has a typically-horizontal planar platform 12 supported by four vertical legs 14, 16, 18, 20 (16 and 20 not shown in FIG. 1). The legs 14, 16, 18, 20 are made of tubular steel having a rectangular cross-section.
The platform 12 is supported in place with respect to the legs 14, 16, 18, 20 by a front platform support assembly 22 and an identically-structured rear support assembly 24 (not shown). The front support assembly 22 extends laterally between the two front legs 14, 18. The rear support assembly 24 extends laterally between the two rear legs 16, 20 (not shown in FIG. 1). Each support assembly, e.g., 22, is adapted to slide up and down on the legs, e.g., 14, 18, between which the support assembly 22 extends. The support assembly 22 also has a guard rail 23 secured to the support assembly 22 in order to move up and down with the support assembly 22.
The support assembly 22 has one pin connection sub-assembly 26 on one end 28 of the support assembly and a second pin connection sub-assembly 30 on the opposite end 32 of the support assembly. A central lateral steel support tube 34, of rectangular cross-section, interconnects the opposing sub-assemblies 26, 30. Each sub-assembly, e.g., 26, secures the associated support assembly 22 to an associated support leg, e.g., 14, on the scaffold 10.
Each sub-assembly 26 has an upper transverse end 31 which extends from, and is integral with, the support tube 34. The sub-assembly 26 also has a pin-housing 36 with a housing axis C--C oriented at an acute angle to the axis A--A of the support leg 14, to the axis B--B or the lateral support tube 34, and to the plane of the platform 12. The sub-assembly 26 also has a vertically-extending U-shaped leg brace 40 that embraces and abuts the outer periphery of the support leg 14. On the external side of the leg brace 40 opposite the support leg 14, the leg brace 40 also abuts and is welded to the lowermost vertical edge 38 of the pin-housing 36. From its junction with pin-housing 36, the leg brace 40 extends typically vertically upwardly to abut the upper transverse end 31 of the sub-assembly 26. The steel leg brace 40 is welded to the upper transverse end 31, rendering the junction of the leg brace 40 and the support tube 34 rigid.
Referring now to FIG. 2, a group of parallel steel railings 46, 48, 50, 52, 54 extend laterally between and rigidly interconnect the front and rear support legs 14, 16 on, as shown in FIG. 1, one side 44 of the scaffold 10. Each leg, e.g., 14, has a series of laterally-spaced pin apertures, e.g., 60, 62, 64, 66, extending along the axial length of the leg 14 on, as shown in FIG. 1, the internal side 68 of the leg 14 adjacent the platform 12. The other pair of legs 18, 20 are similarly interconnected by associated railings (not shown).
Referring now to FIG. 3, the pin connection sub-assembly 26 has a steel connecting pin or rod 56 slidably mounted within a steel pin tube 59 removably but rigidly mounted within the steel pin housing 36. The pin 56 has a rounded protruding end 58 penetrating through a pin aperture 62 in the side wall 68 of the leg 14 and a coaxial leg brace aperture 70 in the leg brace 40 in the sub-assembly 26 between the leg's side wall 68 and the pin housing 36. The axis of the pin 56 (and the parallel axis C--C shown in FIG. 1) is preferably at an angle of 56.66 degrees from the axis A--A of the support leg 14. Similarly, the axis of the pin housing 36 has the same orientation. The upper open end 72 of the pin-housing 36, however, abuts and is welded to the steel support tube 34, which is coextensive at that point with the upper transverse end 31 of the sub-assembly 26.
The pin connection sub-assembly 26 thus provides a very strong, triangularly-shaped structure for the support tube 34 and the platform 12 mounted on the support tube 34. In addition, the angular penetration of the pin 56 into the leg 14 provides a rigid connection between the sub-assembly 26 and the leg 14. In this regard, as shown in FIG. 3, the pin 56 is completely restrained from transverse movement away from the leg 14 by the downward force of the pin 14 against the side wall 68 of the leg 14 and by the resistance imposed by the side wall 68 and by the abutting section 71 of the leg brace 40 against any transverse movement (i.e., non-sliding) of the pin 56 through the side wall 68 and abutting brace section 71 and away from the leg 14. Also, in ordinary usage of the scaffold 10 (as shown in FIGS. 1 and 3), when the load on the platform 12 increases: (i) the downward pressure on the junction of the pin 56 and leg 14 increases; (ii) the connection of the pin 56 and the leg 14 becomes more secure and rigid; and (iii) the interconnection of the support tube 34, pin-connection sub-assembly 26, and leg 14 also becomes more secure and rigid. This structure in FIG. 3 therefore virtually eliminates any possibility that the support tube 34 will accidentally or unintentionally pull away from or move with respect to the associated support leg 14.
The pin 56 has a cap nut 76 welded to the pin 56 opposite the protruding end 58. Intermediate the portion of the pin 56 in the pin tube 59 and the protruding end 58 is a planar, rectangular steel pin handle 78 welded to the pin 56 and slidable with the pin 56 within the pin housing 36. A steel pin spring 74 surrounds the pin 56 intermediate the pin handle 78 and the pin tube 59. The pin spring 74 urges or biases the protruding end 58 to extend outwardly from the pin housing 36. The pin handle 78 is accessible from outside the pin housing 36 so that an operator may readily grasp the pin handle 78 and push on the handle 78, against the pressure of the spring 74, to slide the handle 78 and thus the pin 56 within the housing 36 and away from the leg 1. The spring 74 is enclosed in the pin housing 36 beneath cover 116, reducing the possibility of damage (see also FIG. 1 and FIG. 4).
In this regard, the handle 78 is virtually impossible to move unless all loads are first removed from the platform 12 and support tube 34. Any substantial load on the platform 12, such as a person standing thereon, will cause the friction between the pin 56 and the leg 14 to be so great as to prevent the movement of the handle 78 within the housing 36 or of the pin 56 away from the leg 14. One of the advantages of the present invention is that pin assembly 26 includes locking means and support means in a single unit. This simplifies construction and reduces cost of the invention.
Referring now to FIG. 4, the pin housing 36 is constructed of tubular steel with a cut-out opening 80. As shown in FIGS. 1 and 3, the cut-out 80 extends along the axial length of the pin housing 36 from its junction with the leg brace 40 up to the portion of the pin housing 36 surrounding the pin tube 59 when the pin tube 59 is in the secured, operating position of FIGS. 1 and 3. Referring again to FIG. 4, the pin tube 59 is secured in place within the pin housing 36 by a tube plate 82 to which the pin tube 59 is welded. In turn, the steel tube plate 82 is riveted to the back wall 84 of the pin housing 36 on the internal side of the housing 36 opposite the cut out opening 80.
Referring now to FIGS. 1, 3, and 4 collectively, the pin 56, pin tube 59, and tube plate 82 can all be removed from the pin housing 36 for repair or replacement when the scaffold 10 is dis-assembled. This is accomplished by popping the rivets, e.g., 86, from the pin housing 36 and tube plate 82, and sliding the pin 56, pin spring 74, pin tube 59, and tube plate 82 through the open end 72 in housing 36. The items removed in this fashion can then be re-mounted within the pin housing 36 by reversing this procedure and replacing the securing rivets, e.g., 86.
Referring now to FIG. 5, the platform 12 is rectangular and mounted transversely between the legs 14, 16, 18, 20, and their associated leg braces 40, 88, 90, 92. The platform 12 has a plywood central planar section 95 and a steel u-shaped cap 94 that surrounds all four edges 96, 98, 100, 102 and embraces a co-extensive portion of the upper planar side 104 and opposing lower planar side 106 (not shown in FIG. 5) of the central section 95. The cap 94 is secured to the central section 95 by means of rivets, e.g., 112, 114, penetrating through the cap 94 and central section 95.
The platform 12 also has two steel spacers 108, 110 welded to the U-shaped cap 94 on the side of the cap 94 opposite the side abutting the edge 96, 100 of the central section 95.
The spacers 108, 110 are located on or adjacent the cap 94 so that one spacer 108 is between and abuts one leg 16 and the cap 94 on one lateral side of the platform 12, and the other spacer 110 is between and abuts a leg 18 and the cap 94 on the diametrically opposing lateral side of the platform 12. The spacers 108, 110 respectively push against their adjacent braces 88, 90 and, in turn, support legs 16, 18 to eliminate play or space between these otherwise loosely associated components of the scaffold 12.
In this regard, the leg braces 40, 88, 90, 92 are designed to loosely surround their associated support legs 14, 16, 18, 20 in order to slide along the outer periphery of the support legs 14, 16, 18, 20 when desired. Although the junction of a pin, e.g., 56, with an associated leg, e.g., 14, serves to secure the pin connection sub-assembly, e.g., 26, to the leg 14, some play may remain at the junction of the legs 14, 16, 18, 20 with the associated leg braces 40, 88, 90, 92. The two opposing spacers 108, 110 on or adjacent the platform 12 force any remaining play or looseness between associated structures in the scaffold 10 sufficiently out of the scaffold 10 that the scaffold 10 becomes quite rigid and secure.
Referral to FIGS. 3 and 5, angles 115 are attached to support tube 34 and attached to leg brace 40 to secure the platform in place on top of support tube 34.
As long as platform 12 is on top of locking pin 56 and nut 76, it is virtually impossible for scaffold 10 to come apart.
It can therefore be seen that the present invention provides, among other things, a scaffold that is easily assembled, used, adjusted, disassembled and moved. It is also, however, economical and easy to manufacture, and rigid, strong, and safe when assembled. The scaffold will not come apart unintentionally during ordinary use. It holds its platform securely in place, and the more weight on the platform (within the capacity of the materials utilized in the scaffold), the more secure the connection between the legs and the platform support structure.
Having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the present invention as described by the claims below. | A scaffold having a platform, support legs, support beams supporting the platform, side rails connecting the legs, guard rails, and spring-biased slidable pins securing the support legs to the support beams. Each slidable pin is at an acute angle to the plane of the support platform and axis of its associated support leg and support beam (preferably at 56. degrees to the axis of the associated support leg). This acute-angle pin structure renders that scaffold more rigid and secure while preserving the ability to easily assemble, adjust, and dis-assemble the scaffold. The platform also includes spacers inserted between the platform and support legs to force the legs away from the platform, eliminate play in the structure, and make the scaffold more rigid and secure. | 4 |
TECHNICAL FIELD
The present invention relates to remedial work on oil, injection, gas and other wells and is more specifically concerned with an arrangement for cleaning the internal surface of casing strings.
BACKGROUND OF THE INVENTION
The present invention is intended for a complete and qualitative cleaning of casing string sections from any deposits and built-up metal, as well as for restoring a complete passability of separate well bore sections along the inside diameter. The arrangement is operated in drilling mud, water, oil and mineralized stratum fluid.
In addition the present invention may advantageously be used for cleaning tubular heat exchangers of scale (in the process of overhaul) and other tubular internal surfaces with a constant or slightly varying inside diameter.
The practical remedy of casing strings by means of steel patches proves that a positive result of this operation is possible only if the internal surface of the pipes is thoroughly cleaned along the string section wherein the patch it to be installed.
The presence of corrosion products, cement cake, deposits of salts, as well as burrs and built-up metal on the walls of a casing string in the zone of perforation excludes the snug bearing of the patch against the casing pipe and consequently the achievement of the tightness thereof. When the patch is expanded in a contaminated casing pipe, it may be displaced along the casing string.
The use of pressuring packers and packers to be installed on the tubing string in injection wells, as well as the use of other downhole equipment requiring the snug bearing against the pipe wall (formation testers, and so forth) or power cooperation therewith (anchors) are likewise hampered.
Known in the prior art is a mechanical scraper for cleaning casing strings (Composite Catalog, v. 1, 1984-1985, pp. 808-809, model "C-3", roto-vert, casing scraper, product 620-03), comprising a massive hollow body externally accommodating cutting blades constantly forced by springs against the wall of a casing string under cleaning. The scraper design contemplates the use of a plurality of sets of changeable cutting blades each of which is intended for operation in a narrow range of well bore inside diameters (depending on standard sizes of casing pipes and thickness of their walls).
The mechanical scraper is run in a well to a section to be cleaned on a drill pipe string or tubing string and is commonly operated in conjunction with recirculation of the washing fluid for carrying the products of cleaning away from the wall to the surface.
The process of cleaning may be accomplished both by rotating the scraper and feeding it simultaneously downwards, and by reciprocating it along the string.
The first method is more efficient, however, it is used preferably for cleaning casing pipes of soft and homogeneous deposits of salts, gypsum, mud cake, etc. However when a casing string is to be cleaned of a cement cake, it is recommended to rotate the scraper and simultaneously to drill out the cement bridging plug.
When cleaning the casing string of hard heterogeneous deposits, and moreover when dealing with burrs and built-up metals in the zone of perforation, rotation of the scraper leads to jerks and twisting of the string resulting in jamming and break of the pipes.
For cleaning in such conditions, it is recommended to use the reciprocating motion of the scraper.
A disadvantage of the heretofore described method resides mainly in a low efficiency of cleaning resulting from an inconsiderable force exerted by cylindrical or flat springs for pressing the cutting blades against the surface being cleaned. The force applied to one cutting blade in an appropriate range of the well bore inside diameters comprises 0.7-1.5 kN which corresponds to an average specific load of 0.1-0.2 MPa on the working surface and may ensure only a low-efficient surface attrition. A small working range of compression of the springs limits the radial travel of a cutting blade (up to 5 mm) which involves the use of a plurality of sets of cutting blades in each standard size of the scrapers.
The fact that the cutting blades of a mechnical scraper are constantly forced against the surface being cleaned involves difficulties in entering the scraper in a casing string, reduces the speed of the scraper running the well because of a possible sticking in contaminated sections of the string and in well bore sections with an excessive curvature. This causes an additional wear of cutting edges. In the casing string sections with cracks, burnouts and especially in the zone of perforation, the speed of the scraper running is limited down to 10 m/min, as despite inconsiderable force the cutting blades may thrust against hard projections or sink in the spaces therebetween, thereby causing sticking of the tool with hazardous consequences.
Cleaning the casing string of hard deposits requires prolonged multihour operation of the scrapers, however metal projections on the string surface remain quite unaffected by cleaning.
Also known in the prior art is a hydromechanical arrangement for cleaning uncased well bores of loose mud cake (SU, A No. 649,829).
The arrangement is provided with an elastic extending vessel accommodated in the body. While expanding under the action of a pressure differential, the vessel acts directly on pivoted segments (cutting blades), thereby extending them from the slots of the body until they come in contact with the surface to be cleaned. The pivoted segments in are installed in the body on pivot pins. In order to fasten the ends of the vessel, a bushing with ducts for passage of fluid is provided thereinside. The hydromechanical arrangement is designed for mud grouting of the walls of uncased well bore in the process of drilling. The arrangement has run-in and working positions. The arrangement is changed over from the run-in to the working position under the action of a pressure differential built up in the working space due to the slush nozzles of a bit after lowering in the well to the section to be cleaned.
The arrangement is operated only by means of rotary motion at a slight pressure differential which along with the action of the centrifugal force on the pivoted segments provides on the contacting surface a force sufficient for a partial cleaning and a loose mud cake grouting. The arrangement is designed for operation on the shaft of a turbodrill.
Disadvantages of this arrangement preventing its effective use for cleaning the casing strings reside in the following.
Effective cleaning of a casing string from built-up metal and dense deposits requires that the cutting blade is pressed against the casing pipe wall with a force of several tons to which corresponds operation of the scraper at a pressure differential of 4-6 MPa. When the cutting blade is extended into the working position the vessel walls are subjected to extension. A sharp bend and an additional local extension of the vessel elastic material are caused under the action of the pressure differential on the shoulders between the body and the extended cutting blade, especially in a longitudinal section of the scraper. Besides, at a great pressure differential the elastic material of the vessel is forced (flows) in the clearance between the body and the movable cutting blade and is further pinched (seized). Multiple extension on the shoulders and pinching of the elastic material leads to a rapid destruction of the vessel.
When casing strings are under overhaul the scraper is usually run in on the tubing allowing the cleaning to be carried out only by the reciprocating motion without rotating the scraper when fails to ensure the effective cleaning of the internal surface of the casing strings from hard deposits and built-up metal. The scraper with the pivoted cutting blades (segments) is not fit for operation in such conditions, as the cutting blades have a slight almost linear contact with the circumference of the surface being cleaned.
The arrangement is not provided with a mechanism for returning the pivoted segments to the run-in position after release of the pressure.
ESSENCE OF THE INVENTION
It is an object of the invention to provide an arrangement for cleaning the internal surface of casing strings allowing the internal surface of the casing strings to be effectively cleaned of hard deposits and built-up metal.
The invention resides in that in an arrangement for cleaning the internal surface of casing strings, comprising a hollow cylindrical body with slots provided around the circumference thereof and accommodating extendable cutting blades moved with the aid of walls of an elastic vessel which is adapted to be communicated with a compressed fluid medium source and is internally accommodated in a bushing disposed coaxially with the body and provided with longitudinal ports arrangement opposite to the slots of the body and equipped with flat spring elements which substantially completely cover the ports in the bushing and cooperate by one side with the cutting blades and by the other side, with the elastic vessel.
Such an embodiment of the arrangement for cleaning the internal surface of casing strings provides the conditions for a reliable operation of the vessel at an excess pressure of 5-6 MPa and upward, and ensures the transmission of a force of 30-50 kN to each cutting blade. Action of the cutting blades under such forces on the surface to be cleaned radially improves the efficiency of cleaning.
It is desirable that the outside diameter of the bushing be substantially equal to the inside diameter of the body.
Such a solution makes it possible to provide a built-up body in which the registered spaces (slots of the body and ports of bushings) suitably accommodate the means through the medium of which the elastic vessel cooperates with the cutting blades.
As a result, it becomes possible to use higher pressures without any harm to the strength of the elastic vessel and consequently to improve the efficiency of cleaning.
The flat spring elements may advantageously be made in the form of arc-shaped springs projecting by the convex portions thereof inside the bushings through the ports and having the flat ends disposed in recesses provided on the external surface of the bushing.
When the cutting blade is extended until it comes in contact with the surface to be cleaned, the arc-shaped portion of the spring straightens out, thereby covering the ports of the bushing without any clearances and shoulders in the longitudinal section and forming only minimal shoulders in the cross-section. In addition, the arc-shaped embodiment of the flat spring provides the change-over of the arrangement from the working to the run-in position by retraction of the cutting blades in the body slots accomplished after release of the pressure.
It is preferred that the elastic vessel be made of a rubber-fabric. material.
Reinforcement of the vessel material with a fabric adds strength to the vessel walls by many fold, thereby preventing the flow-in and subsequent pinching of the elastic material under the action of a great pressure differential. As a result, the vessel durability and the value of an excess working pressure are sharply increased.
It is advantageous to dispose the cutting blades at least in two rows so that their cutting edges cover the entire perimeter of the circle circumscribed by the fully extended cutting blades divided into two groups, in one of which the cutting edges of the blades are made sloping to the left and in the other group the cutting edges are made sloping to the right.
When employing the main method of cleaning a casing string by the reciprocating motion of the arrangement, such an embodiment eliminates the need for a periodical turning of the scraper and in addition guarantees the counterbalancing of tangential forces brought about in the arrangement due to sloping disposition of the cutting edges on the blades.
The spring elements may suitably be connected with the cutting blades for limited movement relative to one another.
Such a connection provides the efficient contact between the flat spring and the cutting blades in the process of force transmission and the full retraction of the cutting blades in the scraper body in the run-in position.
SUMMARY OF THE DRAWINGS
The objects and advantages of the invention will become more apparent from the following description in which the preferred embodiment is set forth in detail in conjunction with the accompanying drawings, wherein:
FIG. 1 is a view partly in longitudinal section illustrating the arrangement for cleaning the internal surface of casing strings, according to the invention;
FIG. 2 is a section taken on line II--II of FIG. 1;
FIG. 3 is a section taken on line III--III of FIG. 1;
FIG. 4 diagrammatically illustrates on an enlarged scale two extreme positions of the flat spring element during its displacement in longitudinal ports 11.
DETAILED DESCRIPTION OF THE INVENTION
The diagrammatic sketch illustrating the proposed arrangement partly in a longitudinal section is presented in FIG. 1. The arrangement in the run-in position is shown in the sketch to the left of the centre line and in the working position, to the right of the centre line.
An arrangement comprises a hollow cylindrical body 1 (FIG. 1) with subs 2 and 3 for connection to a string 4 and a bit (or connection) 5. Extendable cutting blades 7 are disposed in peripheral slots 6 of the body 1. The cutting blades 7 and other elements of the arrangement construction are also illustrated in FIG. 2 and FIG. 3 in the run-in and working positions respectively. An elastic vessel 8 is disposed inside the arrangement. A space 9 of the vessel 8 is communicated at the top portion with a source of compressed fluid medium, i.e. with a pumping unit (not shown) by means of a tubing string or a drill pipe string through which the drilling fluid (i.e. fluid medium) is injected in the well. At the bottom portion the space 9 of the vessel 8 is communicated with nozzles of the bit (connections) 5 by means of which an excess pressure is built up in this space during circulation of the drilling fluid.
Installed between the body 1 and the elastic vessel 8 are intermediate bushings 10 provided with longitudinal ports 11 which are disposed opposite to the slots 6 of the body 1 and provided with flat spring elements 12 substantially completely covering the ports 11 of the bushing 10.
The flat spring elements 12 made in the form of arc-shaped springs project by their central convex portion inside the bushing 10 through the ports 11. Flat ends of the springs 12 are disposed in special recesses 13 provided on the external surface of the bushing 10 and rest against the body 1.
Ends of the elastic vessel 8 are reliably secured inside the bushings 10 by means of cones 14 and pressure nuts 15, providing a hermetic sealing of the arrangement at a build-up of the excess pressure. Rubber rings 16 are made for the same purpose on the external surface of the bushings 10 which are a running fit in the body 1.
The flat spring elements 12 are connected with the cutting blades 7 by means of screws 17. The connection is made with a definite limited relative mobility which provides an efficient cooperation of the flat spring elements and the cutting blades 7 in transmission of the force and a complete retraction of the cutting blades 7 in the slots 6 of the body 1 when the arrangement is switched over to the run-in position.
The elastic vessel 8 is made of a rubber-fabric pressure hose.
In the run-in position when the cutting blades 7 are retracted in the slots 6 of the body 1, longitudinal folds 18 (FIG. 2) are formed at appropriate places on the surface of the elastic vessel 8 and are straightened out as the cutting blades 7 (FIG. 3) are extended.
To provide a complete engagement of the surface to be cleaned during the reciprocating motion of the arrangement, the extanable cutting blades 7 are disposed in two rows (FIG. 1) having three blades in each row (FIGS. 2 and 3) and displaced through 60°.
In order to counterbalance the tangential forces brought about in the arrangement due to the sloping disposition of the cutting edges, one half of the cutting blades 7 have the cutting edges sloping to the left and one half have the cutting edges sloping to the right.
All the cutting blades 7 have an independent "floating" disposition in the slots 6 of the body 1. If an almost insurmountable obstruction is encountered on the wall of a casing string, (e.g., a large piece of built-up metal) the cutting blade 7 freely retracts in the body 1, thus preventing any danger of the tool jamming.
When assembling the arrangement the cutting blades are inserted in the slots 6 of the body 1 from the inside. Provided on the side surfaces of the cutting blades 7 and respectively in the slots 6 of the body 1 are limiting collars 19 and 20 which prevent the cutting blades 7 from falling out in the well during operation of the arrangement.
The arrangement operates in the following way. In the run-in position, when the arrangement is run in and pulled out of a well, the cutting blades 7 are retracted in the slots 6 of the body 1 by the flat spring elements 12 which rest by their flat ends against the body 1, while their central portions project inside the bushings 10 through the ports 11, thereby making the longitudinal folds 18 on the elastic vessel 8 (FIGS. 1 and 2).
The possibility of changing over the arrangement to the run-in position, i.e. to cut the arrangement out of operation, in which the cutting blades 7 are retracted the slots 6 of the body 1, makes it possible to run in the arrangement to the section to be cleaned and to pull it out without any troubles and speed restrictions. The arrangement is entered in a casing string without any hinderance.
After the arrangement has been run in the section to be cleaned the circulation of the drilling fluid through the string of pipes 4 is restored and an excess pressure of 3-6 MPa is built up in the space 9 of the elastic vessel 8. The value of excess pressure is controlled by changing the diameter of the drilling fluid passages of the connection 5 or more expeditiously by changing the output of a pumping unit.
When the arrangement is cut into operation the elastic vessel 8 extends the cutting blades 7 from the slots 6 of the body 1 by acting upon them through the spring 12 by its outer wall. The cutting blade is pressed against the surface to be cleaned (FIGS. 1 and 3) with force corresponding to the value of an excess pressure.
The flat ends of the flat spring element 12 constantly rest against the arrangement body 1 and practically do not change their position relative to the bushing 10. The arc-shaped portion of the flat spring element 12 disposed in the longitudinal port 11 of the bushing 10 is straightened out under the action of the wall of the elastic vessel 8, enters the port 11 of the bushing 10 and covers the shoulder between the body 1 and the extended cutting blade 7 in the longitudinal section (FIGS. 1 and 3).
As a result, a bend and a local extension of the elastic material of the vessel 8 forced against the internal surface of the arrangement by the excess pressure are completely avoided in this section.
In the cross-section of the arrangement, a shoulder 21 is formed between the bushing 10 and the flat spring element 12 because of a different thickness of the walls of casing pipes and the deposited layer to be cleaned off.
The height of the shoulder 21 (FIG. 4) varies from h to 2h depending on the difference in thickness of walls of produced pipes. The maximum height of the shoulder 21 for the production casing strings comprises ±2.75 mm.
The longitudinal folds 18 of the elastic vessel 8 are straighened out under the action of the excess pressure and closely fits to the shoulder 21 practically without any local extention of the elastic material.
It should be noted that in the period when the cutting blades 7 are extended from the body 1 till the moment when they come in contact with the surface to be cleaned, the elastic vessel 8 is practically not subject to any load, as it overcomes only the resistance of the spring 12 being straightened out.
During operation of the arrangement the main portion of the elastic vessel 8 is also not subjected to breaking loads, as the excess pressure in the space 9 is completely relieved through the wall of the elastic vessel 8 acting on the internal surface of the bushing 10 and the spring 12. The danger of destruction arises mainly at places where the elastic vessel 8 covers the shoulder 21 with a clearance and conditions arise for flowing of the elastic material in the clearance and for its subsequent pinching (seizing).
The use of the intermediate bushing 10 with the flat spring element 12 makes it possible to eliminate the cause of destruction of the elastic vessel 8 in the longitudinal section and to reduce it to a minimum in the cross-section (due to the minimum value of the height of the shoulders 21).
Reinforcement with a fabric adds strength to the walls of the elastic vessel 8 by many fold which together with the advantages heretofore described radically improves the durability of the elastic vessel 8 in the recommended range of high working pressures.
Design of the arrangement provides a sufficient radial travel of the cutting blades 7 ensuring the effective use of the arrangement in the entire range of wall thicknesses of the production casing pipes of one standard size; at a definite excess pressure the force with which the cutting blades 7 engage the surface to be cleaned is not dependent on the degree of the cutting blade extension from the body 1 and consequently on the thickness of a pipe wall and deposited layer. Therefore, sets of changeable cutting dies are not contemplated by the design of the arrangement. Diameter of the body 1 is selected so as to ensure the reliable passability of the arrangement through the casing string sections having the maximum wall thickness.
The arrangement is intended for trouble-free and prolonged operation at a great excess pressure which may be expeditiously controlled, depending on the conditions of cleaning. Corresponding to the recommended excess pressure of 5-6 MPa is a load of 30-50 kN acting on each cutting blade in place of 0.7-1.5 kN acting on a spring-loaded cutting blade of a mechanical scraper or respectively an average specific load of 1.5-3.0 MPa acting on the cutting blade in place of 0.1-0.13 MPa. This fact primarily ensures a radical increase in the intensity of cleaning and makes it possible to completely clean off the most hard deposits and built-up metal.
Moreover the intensity of cleaning rises further not in proportion to the rise of the load (25-30 times) but is many times greater due to the fact that the mode of a volumetric destruction of mineral deposits and cutting of metal projections takes place instead of the surface attrition process.
Inspections of the recovered strings have shown that the coats of polymeric materials, epoxy resin, as well as pieces of built-up metal 3-6 mm thick left on the internal surface of pipes after electric welding were completely cleaned off to bright metal in 8-10 passes of the scraper. Metal chips similar to those produced on a planning machine were washed away from the well.
The excess pressure may advantageously be reduced down to 2.5-3 MPa for cleaning off deposits of soft and medium-hard materials to avoid pressing of slag in the channels between the cutting edges of the blades and an excessive contamination of the fluid flow.
A pressure of 5-6 MPa is intended for cleaning off hard deposits. Design of the arrangement readily allows an increase in the load up to 10-15 MPa and upward. However, in this case the dynamics of cleaning process, the axial force required for moving the arrangement, etc. are sharply increased.
The cutting structure of the blades is shaped so that not only projections and deposits are cleaned off without damaging the pipe wall but on the contrary production irregularities left on the pipe wall surface are smoothed out.
A casing string may be cleaned both by imparting a reciprocating motion to the arrangement and by rotating and gradually feeding the arrangement downwards.
A reliable control of the cleaning process is feasible. | An arrangement for cleaning the internal surface of casing strings, comprises a hollow cylindrical body with slots provided around the periphery thereof. The slots accommodate extendable cutting blades. The cutting blades are moved with the aid of walls of an elastic vessel. The elastic vessel is disposed inside the body and adapted to be communicated with a source of compressed fluid medium. The elastic vessel is disposed in a bushing installed coaxially with the body and provided with longitudinal ports. The ports are arranged opposite to the slots of the body and are equipped with flat spring elements. The flat spring elements substantially completely cover the ports of the bushing and cooperate by one side with the cutting blades and by the other side, with the elastic vessel. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the protection against overcurrents in transistors carrying a load supply current and, for example, to the protection of transistors connected in parallel to control an at least partially inductive load, and more specifically the forming of individual circuits for protecting these transistors on demagnetization of the inductive load.
2. Description of the Related Art
FIG. 1 shows a conventional example of an assembly of several MOS power transistors M (M 1 , . . . Mn) connected in parallel between a terminal 1 of application of a supply voltage Vbat (for example, the voltage of a battery) and a terminal 2 of connection to a load Q to be powered, the other end of the load being for example connected to ground 3 . In the example of FIG. 1 , only two transistors M 1 and Mn have been shown. In practice, the number n of parallel-connected transistors M depends on the power required by the load and on the current that each transistor can individually conduct.
All transistors M 1 to Mn are controlled from a same signal CTRL that they respectively receive via logic and level-adapting blocks B 1 to Bn (LOG) (for example, charge pump, set-up circuits, etc.) on their respective control terminals (gate) G (G 1 to Gn). The respective conduction terminals (drain and source) of transistors M are directly connected to terminals 1 and 2 .
Each transistor M is associated with a protection circuit formed of a zener diode DZ (DZ 1 , . . . DZn) in anti-series with a respective diode D (D 1 , . . . Dn) between terminal 1 and gate G of the concerned transistor.
When transistors M 1 to Mn are controlled to be turned on by signal CTRL, load Q is supplied with voltage Vbat. Diodes DZ 1 to DZn are reverse-biased. Diodes DZ have no function in the conduction phase since their threshold voltages are greater than the supply voltage, so that the voltage difference between control signal CTRL and voltage Vbat does not place them in avalanche when signal CTRL is active to turn on transistors M.
When transistors M 1 to Mn are controlled to be turned on by a state switching of signal CTRL, a problem of current distribution is traditionally posed in power transistors. This problem is particularly present in the case of an at least partially inductive load due to the demagnetization phenomenon. This demagnetization results in the voltage at terminal 2 becoming lower than the voltage at terminal 3 (the ground), which considerably increases the voltage difference between terminals 1 and 2 . To carry off the demagnetization current, transistors M 1 and Mn must be turned on until this current disappears. This is the function of diodes DZ 1 to DZn which set the demagnetization voltage, that is, the voltage across inductive load Q in the carrying off in the power supply of the demagnetization current. In fact, when the voltage of terminal 2 is lowered by the demagnetization to a value such that the voltage difference between terminals 1 and 2 exceeds the threshold voltage of diodes DZ, (neglecting gate-source voltage Vgs of transistors M and voltage drop VD in each forward-biased diode D), these diodes start an avalanche and impose a positive voltage between the gate and source of the corresponding transistors M to turn them on.
When control signal CTRL is inactive, demagnetization voltage Vdemag (the voltage across load Q) can be written, for each transistor M, as:
V demag= V bat−( VDZ+VD+Vgs ),
where VDZ represents the threshold voltage of zener diode DZ.
Forward voltage drops VD of diodes D are all fixed (on the order of 0.6 V), just as voltages Vgs of the different MOS transistors are approximately fixed, as well as battery voltage Vbat. Accordingly, in the above relation, it can be seen that the single parameter which conditions demagnetization voltage Vdemag of the load is the threshold voltage of zener diodes DZ.
Zener diodes DZ 1 to DZn are thus all selected to have the same nominal values, to set the same demagnetization voltage, for the entire assembly, and distribute the current in all branches.
A disadvantage of the circuit of FIG. 1 is that manufacturing tolerances and technological dispersions make the respective threshold voltages of the different zener diodes DZ 1 to DZn of the protection circuits of transistors M 1 to Mn vary from one branch to another. This problem is particularly present in the case where each power transistor M is integrated with its protection circuit and its logic block in a circuit separate from the other transistors which are then associated in parallel in an assembly such as shown in FIG. 1 . The presence of blocks B prevents a direct interconnection of all the gates of transistors M, which imposes providing one protection circuit (diodes DZ and D) per branch.
In fact, the zener diode DZ which has the smallest threshold voltage conducts first and thus imposes on its transistor a positive voltage Vgs to turn it on to carry off the demagnetization current. Since the other transistors M are not on yet because the protection zener diodes DZ associated therewith have greater thresholds, all the current flows through a single transistor M and said transistor is thus damaged since it is not designed to stand all of the current.
BRIEF SUMMARY OF THE INVENTION
The disclosed embodiments of the present invention maintain the balance between currents in the difference branches of a parallel association of several transistors in a demagnetization of an inductive load despite possible technological challenges and manufacturing tolerances of zener protection diodes.
In one embodiment of the present invention a circuit for protecting a transistor is provided. The circuit includes at least one break-over component in anti-series with a one-way conduction element coupled between a first conduction terminal and a control terminal.
These include a resistive element in series with the break-over component; and
a controllable current source between a terminal of the one-way conduction element opposite to said transistor and a second conduction terminal of the transistor.
According to an embodiment of the present invention, the current source is controlled according to the current in the transistor.
According to an embodiment of the present invention, the second conduction terminal of the transistor is intended to be connected to an at least partially inductive load, the current source belonging to a circuit for decreasing a demagnetization voltage set by the break-over component.
According to an embodiment of the present invention, the demagnetization voltage is lowered if the current in the transistor becomes greater than a threshold.
According to an embodiment of the present invention, the break-over component is a zener diode.
According to an embodiment of the present invention, the transistor is a MOS transistor.
The disclosed embodiments of the present invention also provide a circuit for supplying a load with several transistors coupled in parallel and connected between a first terminal of application of a supply voltage and a first terminal of the load, each transistor associated with a protection circuit.
According to an embodiment of the present invention, the load is at least partially inductive.
The present invention also provides a method for protecting a control transistor to supply an at least partially inductive load, the method including the step of lowering the demagnetization voltage of the load with respect to a demagnetization voltage set by a break-over component connected between a conduction terminal and the control terminal of the transistor.
In accordance with another embodiment of the invention, a circuit is provided that includes first and second parallel-coupled transistors, each transistor having a first terminal coupled to a supply terminal, a second terminal coupled to a load terminal, and a control terminal to receive a control signal; and a protection circuit, the protection circuit including a first diode coupled in series to a second diode between the first terminal of each transistor and the control terminal of each transistor, a first resistive element coupled in series with the first and second diodes, and a current source coupled between a first terminal of the resistive element and the load terminal.
In accordance with another aspect of the foregoing embodiment, the first diode comprises a zener diode with a cathode coupled to the supply terminal and the second diode has a cathode coupled to the control terminal of the respective transistor. Ideally, the first resistive element is coupled between the first and second diodes with the first terminal of the resistive element also coupled to an anode of the second diode.
In accordance with another aspect of the foregoing embodiment, a control circuit is coupled to the second terminal of each transistor and to a control terminal of the current source.
In accordance with another embodiment of the invention, a circuit is provided that includes a power transistor having a first terminal coupled to a supply terminal and a second terminal coupled to a load terminal, and a control terminal configured to receive a control signal; and a protection circuit that includes an auxiliary transistor having a first terminal coupled to the supply terminal and a second terminal coupled to the control terminal of the power transistor; a first diode having a cathode coupled to the supply terminal and an anode coupled to the first terminal of the auxiliary transistor; a second diode having an anode coupled to a control terminal of the auxiliary transistor and a cathode coupled to the anode of the first diode; a first resistor coupled to the anode of the first diode and to the control terminal of the auxiliary transistor; and a current source coupled between the control terminal of the auxiliary transistor and the load terminal, the current source including a line coupling a second terminal of the current source to an auxiliary terminal of the power transistor.
In accordance with another aspect of the foregoing embodiment, the current source includes a first transistor having a first terminal coupled to a control terminal of the auxiliary transistor, a second terminal coupled to the load terminal, and a control terminal, and further including a second transistor having a first terminal coupled to a current supply, a second terminal coupled to the load terminal, and a control terminal coupled to the control terminal of the first transistor in the current source, the second terminal of the second transistor including the third terminal of the current source that is coupled to the auxiliary terminal of the power transistor.
In accordance with yet a further aspect of the foregoing embodiment, the circuit includes a resistive element coupled between the second terminal of the second transistor and the load terminal.
In accordance with a further aspect of the foregoing embodiment, a threshold voltage of the second diode is smaller than a threshold voltage of the first diode.
In accordance with yet another embodiment of the invention, a protection circuit is provided for a power transistor having a first conduction terminal, a second conduction terminal, and a control terminal configured to receive a control signal and at least one other transistor coupled in parallel to the power transistor, the at least one other transistor having a first terminal coupled to the first conduction terminal and a second terminal coupled to the second conduction terminal and a control terminal. The protection circuit includes means for sensing current in each of the power transistor and the at least one other transistor; and means for diverting current from one of the power transistor and the at least one other transistor that is conducting a maximum current, the diverting means responsive to the sensing means, and the diverting means further configured to cause the other of the power transistor and the at least one other transistor to conduct current in response to the sensing means.
In accordance with another aspect of the foregoing embodiment, the sensing means includes a breakover component coupled between the first conduction terminal and the control terminal of the respective power transistor and the at least one other transistor, a one-way conduction element coupled between the breakover element and a control terminal of the power transistor and the respective at least one other transistor, and at least one resistive element coupled between the breakover component and the one-way conduction element.
In accordance with yet another aspect of the foregoing embodiment, the diverting means includes a current source having a first terminal coupled to a node formed by the coupling of the first resistive element and the one-way conduction element and a second terminal coupled to the second conduction terminal of the respective power transistor and the at least one other transistor, and a control circuit coupled to a control terminal of the current source and to the second conduction terminal of the respective power transistor and the at least one other transistor.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The foregoing and other features and advantages of the present invention will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings, wherein:
FIG. 1 , previously described, is intended to show the state of the art;
FIG. 2 schematically shows in the form of blocks an embodiment of circuits for protecting power transistors according to the present invention; and
FIG. 3 shows a detailed embodiment of a power transistor and of its protection circuit according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In the figures, the same elements have been designated with same reference numerals in the different drawings. For clarity, only those elements that are necessary to the understanding of the present invention have been shown and will be described hereafter. In particular, the structure of the load supplied by several parallel power transistors has not been shown, the present invention being compatible with the load conventionally controlled by transistors in parallel. Further, the generation of the control signals of these power transistors has not been shown and is compatible with conventional systems.
The disclosed features of the present invention will be described hereafter in relation with an example applied to MOS power transistors. It should however be noted that the implementation more generally applies whatever the nature of the transistor, for example, a bipolar transistor.
FIG. 2 schematically (and partially in the form of blocks) shows an embodiment of MOS power transistor protection circuits according to one embodiment of the present invention.
As previously described, several (n) MOS power transistors M 1 to Mn are connected in parallel between a terminal 1 of application of a supply voltage Vbat (for example, the D.C. voltage of a battery) and a terminal 2 intended to be connected to a first conduction terminal of a load Q having its other terminal connected, for example, to ground 3 .
According to the shown embodiment, the control electrode (gate) of each transistor M is connected to terminal 1 by a series association of a zener diode DZ (DZ 1 to DZn), of a resistor R (R 1 to Rn), and of a diode D (D 1 to Dn). The cathode of each diode DZ is directly connected to terminal 1 while the cathode of each diode D is directly connected to gate G (G 1 to Gn) of the transistor M with which it is associated. Each gate G receives a control signal CTRL via a conventional block B (B 1 to Bn). As an alternative, resistor R is interposed between the cathode of diode DZ and terminal 1 .
The resistor R is interposed between the respective anodes of diode DZ and of diode D. The function of resistor R is to effectively increase the threshold voltage of zener diode DZ to lower the source voltage of transistor M and thus the demagnetization voltage of the load.
The anode of diode D is further connected to terminal 2 by a controllable current source 10 . The source 10 of each stage is individually controlled by a circuit 11 associated with the concerned stage which, in the shown example, measures the current in the main branch (in the involved transistor M) by means of a resistor RS (RS 1 to RSn) connecting source S (S 1 to Sn) of each transistor to terminal 2 .
As in conventional embodiments, the different zener diodes used are provided to have a same nominal threshold voltage but may have different real threshold voltages from one diode to the other due to technological dispersions and/or manufacturing tolerances.
Here, however, when the first zener diode (that having the smallest real threshold voltage) starts an avalanche, and turns on the transistor M which is associated therewith, the current flow through this transistor starts the corresponding current source 10 via circuit 11 . In practice, circuit 11 triggers current source 10 with respect to a threshold for example selected according to the maximum current that transistor M withstand. The higher the current in transistor M (measured by resistor RS), the higher the current in source 10 .
The current diversion from the supply voltage to node 2 due to source 10 functionally decreases the level of the demagnetization voltage, that is, of the voltage of terminal 2 . Now, by decreasing the voltage of terminal 2 , the starting of the other branches having higher threshold voltages of their corresponding zener diodes is accelerated. Thus a single branch does not have to withstand the entire demagnetization current.
It can be seen that, in a first phase, the current in the transistor M that conducts first is maximum, that is, it absorbs the entire demagnetization current. During this phase, the current in zener diode DZ corresponds to the nominal current for which this diode is provided based on its threshold voltage. However, this first phase does not last. Due to the decrease in the voltage at node 2 by the action of the current diversion by source 10 , the other branches turn on, which places all branches in a second phase where the current in the zener diode corresponds to the nominal value and where the current is distributed in transistors M in balanced fashion.
As an alternative, the temperature of transistors M may be measured, rather than the currents that they conduct.
FIG. 3 shows a detailed example of an integrated circuit 20 containing a power transistor (here, a MOS transistor SM) and a protection circuit according to an embodiment of the present invention. For example, integrated circuit 20 is a tripole having a control terminal 23 connected to the input of block B intended to receive control signal CTRL and having two conduction terminals 21 and 22 intended to be respectively connected to terminals 1 and 2 of an assembly in parallel associating several circuits 20 .
In the example of FIG. 3 , the function of diode D ( FIG. 2 ) is ensured by an auxiliary transistor M′ (for example, MOS) having a conduction terminal connected to the anode of diode DZ and having its other conduction terminal connected to gate G of transistor SM. Resistor R is in this example replaced with a resistor R′ between the anode of diode DZ and the gate of transistor M′ (and thus still in series with diode DZ) and is in parallel with an auxiliary zener diode ADZ which has the function of protecting transistor M′. The threshold voltage of diode ADZ is smaller than that of diode DZ. For example, for a diode DZ on the order of 30 volts, a diode ADZ on the order of a few volts will be sufficient.
In the embodiment of FIG. 3 , to avoid the presence of the detection resistor in series with transistor M ( FIG. 2 ), a current measurement transistor SM (“sense FET”) having an auxiliary terminal 25 providing an image of the current flowing through said transistor SM will be used. Functionally, such a transistor amounts to connecting, between terminal 21 and the measurement input (terminal S) of a block 11 ( FIG. 2 ), an additional transistor (symbolized by auxiliary terminal 25 ) having its gate connected to that of the main transistor.
Terminal 25 is connected to a first terminal of a measurement resistor RS having its other terminal connected to main terminal 22 . The first terminal of resistor RS is further connected to a first transistor 26 (for example, MOS) of a current mirror having its other conduction terminal receiving a constant current 10 . This current originates from a conventional external current source which needs not be detailed. Transistor 26 has its control terminal (its gate) connected to that of another transistor 27 (for example, MOS) and to its conduction terminal receiving current 10 . The two conduction terminals of transistor 27 are respectively connected to the gate of transistor M′ and to terminal 22 . The function of the current mirror formed of transistor 26 , 27 is to form a controllable current source adapting the current diverted by resistor R′ from the current measured by resistor RS.
In the case where the assembly has more than two branches in parallel, once the first branch is conductive, it is not compulsory for the other branches to simultaneously start conducting. Their respective conduction times will depend on the thresholds of their respective zener diodes. However, as long as a detection circuit of one of the branches detects in the main transistor of this branch a current greater than its allowed threshold (set by its circuit 11 , FIG. 2 , or by the structure of its current mirror 26 , 27 , FIG. 3 ), it will attempt to lower the voltage of terminal 2 to start another branch.
An advantage of the present invention is that it compensates for the possible differences between the threshold voltages of the zener diodes of the protection circuits of the parallel-connected transistors.
Another advantage of the present invention is that the different circuits in parallel automatically adapt to the structures of the others. On this regard, it should be noted that each protection circuit associated with a power transistor is formed independently from the other branches. For example, the sizes of the transistors of the different branches may be different from one other, the respective starting thresholds of their protection circuits being then also different. However, the nominal threshold voltages of the zener diodes of the protection circuits are, preferably, selected to all have the same values.
Of course, the present invention is likely to have various alterations, modifications, and improvements which will readily occur to those skilled in the art. In particular, the dimensions to be given to the different components depend on the application and are within the abilities of those skilled in the art based on the functional indications given hereabove. Further, current sources other than those illustrated in FIG. 3 are possible, since other circuits may perform the function of lowering the level of the demagnetization voltage down to the point where the zener diodes of the other branches are triggered. Further, it should be reminded that although the present invention has been described in relation with an application to MOS transistors, it more generally applies whatever the type of transistors (especially bipolar), the adaptations of the voltage controls to turn them into a current control (bipolar case) being with the abilities of those skilled in the art.
Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and the scope of the present invention. Accordingly, the foregoing description is by way of example only and is not intended to be limiting. The present invention is limited only as defined in the following claims and the equivalents thereto.
All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety. | A method and a circuit for protecting a transistor that controls the supply of an at least partially inductive load, including lowering the demagnetization voltage of the inductive load with respect to a demagnetization voltage set by a break-over component connected between a conduction terminal and the control terminal of the transistor. | 7 |
RELATED APPLICATION
[0001] This application claims the priority of U.S. Provisional Application Ser. No. 60/719,247, filed Sep. 21, 2005, entitled SYSTEMS AND METHODS THAT MITIGATE CONTAMINATION DURING ION IMPLANTATION PROCESSES THROUGH THE INTRODUCTION OF REACTIVE GASES.
FIELD OF INVENTION
[0002] The present invention relates generally to ion implantation typically employed in semiconductor device fabrication, and more particularly, to mitigating contamination and/or modifying the surface characteristics of target devices through the introduction of gases during ion implantation.
BACKGROUND OF THE INVENTION
[0003] Ion implantation is, typically, a physical process that is employed in semiconductor device fabrication to selectively implant dopant into semiconductor and/or wafer material. Thus, the act of implanting does not rely on a chemical interaction between a dopant and semiconductor material. For ion implantation, dopant atoms/molecules are ionized, accelerated, formed into a beam, analyzed, and swept across a wafer, or the wafer is swept through the beam. The dopant ions physically bombard the wafer, enter the surface and come to rest below the surface, at a depth related to their energy.
[0004] An ion implantation system is a collection of sophisticated subsystems, each performing a specific action on the dopant ions. Dopant elements, in gas or solid form, are positioned inside an ionization chamber and ionized by a suitable ionization process. In one exemplary process, the chamber is maintained at a low pressure (vacuum). A filament is located within the chamber and is heated to the point where electrons are created from the filament source. The negatively charged electrons are attracted to an oppositely charged anode also within the chamber. During the travel from the filament to the anode, the electrons collide with the dopant source elements (e.g., molecules or atoms) and create a host of positively charged ions from the elements in the molecule.
[0005] Generally, other positive ions are created in addition to desired dopant ions. The desired dopant ions are selected from the ions by a process referred to as analyzing, mass analyzing, selection, or ion separation. Selection is accomplished utilizing a mass analyzer that creates a magnetic field through which ions from the ionization chamber travel. The ions leave the ionization chamber at relatively high speeds and are bent into an arc by the magnetic field. The radius of the arc is dictated by the mass of individual ions, speed, and the strength of the magnetic field. An exit of the analyzer permits only one species of ions, the desired dopant ions, to exit the mass analyzer.
[0006] An acceleration system is employed to accelerate or decelerate the desired dopant ions to a predetermined momentum (e.g., mass of a dopant ion multiplied by its velocity) to penetrate the wafer surface. For acceleration, the system is generally of a linear design with annular powered electrodes along its axis. As the dopant ions enter therein, they are accelerated there through.
[0007] An end station holds one or more target wafers into which an ion beam from the acceleration system implants one or more dopants. The end station is operable to move or scan the one or more target wafers in one or two dimensions as the ion beam strikes the target wafer(s) in order to obtain desired coverage of the target wafer and dose amount in accordance with a prescribed ion implantation process.
[0008] One problem that can occur during the ion implantation process is the unwanted introduction of atomic or molecular contaminant particles into the ion beam. These contaminant particles can be introduced into the beam at various stages of the system, such as within the mass analysis subsystem, the acceleration electrodes and/or the end station. These particles can be undesirably implanted into, or deposited onto, one or more target wafers, resulting in degradation or failure of devices formed thereon.
SUMMARY OF THE INVENTION
[0009] The following presents a simplified summary in order to provide a basic understanding of one or more aspects of the invention. This summary is not an extensive overview of the invention, and is neither intended to identify key or critical elements of the invention, nor to delineate the scope thereof. Rather, the primary purpose of the summary is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented later.
[0010] The present invention discloses methods and systems that mitigate contamination and/or modify surface characteristics during ion implantation processes by introduction of atmospheric or reactive gases during the ion implantation process. It has been discovered that these introduced gas(es) can prevent or mitigate contaminants from being implanted into target devices, such as silicon wafers by one or more mechanisms. While not intending to be confined by theory, it is assumed that one of the mechanisms is the formation of gaseous volatile compounds by the reactive gas, which interact with the contaminants at the target surface, whereby the volatile compounds are then removed by, for example, a cryogenic or turbo-molecular pump. Another mechanism involves the formation of a surface layer, such as a passivation layer, created by the presence of the reactive gas during ion implantation. The surface layer mitigates or prevents implanting of contaminants into underlying layers of the device.
[0011] In accordance with one aspect of the present invention, a contamination mitigation system for ion implantation processes includes a process chamber having a gas source/supply, a controller, and a valve coupled thereto. The gas source, for example, a pressurized gas cylinder, delivers a reactive gas to the process chamber via a valve that is selectively operated by the controller. The valve is located on or about the process chamber and controllably adjusts flow rate and/or composition of the gas(es) delivered to the process chamber. The process chamber holds a target device, such as a target wafer such that the gas(es) is permitted to interact with the ion beam or the wafer surface to mitigate contamination of the target wafer. In one embodiment, the controller can select and adjust the composition of the reactive gas as well as the flow rate according to monitored contaminants present within the ion beam or on the surface of the device or target. Other systems, methods, and detectors are also disclosed.
[0012] To the accomplishment of the foregoing and related ends, the invention comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects and implementations of the invention. These are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a block diagram of an ion implantation system in accordance with one or more aspects of the present invention.
[0014] FIG. 2 is a block diagram of an ion implantation process modification system in accordance with an aspect of the present invention.
[0015] FIG. 3 is a block diagram depicting an interior of a process chamber during an ion implantation process in which a reactive gas in introduced to mitigate contamination in accordance with an aspect of the present invention.
[0016] FIG. 4 is a diagram of an ion implantation process modification system is described in accordance with an aspect of the present invention.
[0017] FIG. 5 is a flow diagram illustrating a method mitigating contamination of a target device by contaminants during ion implantation in accordance with an aspect of the present invention.
[0018] FIG. 6 is a flow diagram illustrating a method mitigating contamination of a target device by contaminants during ion implantation that introduces a reactive gas and measures gas within a process chamber during ion implantation in accordance with an aspect of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention will now be described with reference to the attached drawings, wherein like reference numerals are used to refer to like elements throughout. It will be appreciated by those skilled in the art that the invention is not limited to the exemplary implementations and aspects illustrated and described hereinafter.
[0020] As semiconductor devices, such as sub-micron CMOS structures, become smaller and smaller, the ion implantation processes required to modify electrically active regions of semiconductor devices become shallower and more sensitive to the material properties in the surface and near surface regions of the semiconductor devices. Additionally, semiconductor devices are more sensitive to surface contamination from sputtered materials and absorbed gases present during implantation processes, particularly the concentration and distribution of contaminants within active device regions. Contaminants or particles can be implanted with the ion beam and negatively impact diffusion and other properties of formed structures and/or devices. As a result, for example, this contamination can result in undesirable and varied device parameters for fabricated semiconductor devices.
[0021] Particles or atomic contaminants, which are also referred to later as ion beam contaminants, can arise for a variety of sources during ion implantation. For example, carbon can be generated from apertures and other surfaces within the ion implantation system. Typically, the carbon particles are generated by ion beam striking carbon based surfaces such as graphite, which is a commonly used material within ion implantation systems. Additionally, sputtering processes and other deposition mechanisms can release unwanted carbon particles. Additionally, photoresist material, which is commonly used as a mask for ion implantation typically, contains carbon, which can then be released during ion implantation. Although carbon is provided as an example of a type of particle or contaminant, contamination from other materials or types of particles or contaminants is contemplated by the present invention.
[0022] Aspects of the present invention mitigate contamination during ion implantation by employing a reactive gas, such as an atmospheric gas, oxygen containing gas, water vapor, and the like, that reacts with contaminants or particles in order to reduce contamination. Additionally, the reactive gas can also be used to modify the target properties or characteristics determined by previous processes.
[0023] Referring initially to FIG. 1 , an ion implantation system 100 suitable for implementing one or more aspects of the present invention is depicted in block diagram form. The system 100 includes an ion source 102 for producing an ion beam 104 along a beam path. The ion beam source 102 includes, for example, a plasma source 106 with an associated power source 108 . The plasma source 106 may, for example, comprise a relatively long plasma confinement chamber from which an ion beam is extracted.
[0024] A beam line assembly 110 is provided downstream of the ion source 102 to receive the beam 104 there from. The beam line assembly 110 includes a mass analyzer 112 , and an acceleration structure 114 , which may include, for example, one or more gaps. The beam line assembly 110 is situated along the path to receive the beam 104 . The mass analyzer 112 includes a field generating component, such as a magnet (not shown), and operates to provide a field across the beam path so as to deflect ions from the ion beam 104 at varying trajectories according to mass (e.g., charge to mass ratio). Ions traveling through the magnetic field experience a force which directs individual ions of a desired mass along the beam path and which deflects ions of undesired mass away from the beam path.
[0025] The acceleration gap or gaps within the acceleration structure 114 are operable to accelerate and/or decelerate ions within the beam to achieve a desired depth of implantation in a work piece. Accordingly, it will be appreciated that while the terms accelerator and/or acceleration gap may be utilized herein in describing one or more aspects of the present invention, such terms are not intended to be construed narrowly so as to be limited to a literal interpretation of acceleration, but are to be construed broadly so as to include, among other things, deceleration as well as changes in direction. It will be further appreciated that acceleration/deceleration means may be applied before as well as after the magnetic analysis by the mass analyzer 112 .
[0026] An end station 118 is also provided in the system 100 to ion beam 104 from the beam line assembly 110 . The end station 118 supports one or more work pieces, such as semiconductor wafers (not shown), within a process chamber and along the beam path for implantation using the mass analyzed ion beam 104 . The end station 118 includes a target scanning system 120 for translating or scanning one or more target work pieces and the ion beam 104 relative to one another. The target scanning system 120 may provide for batch or serial implantation, for example, as may be desired under given circumstances, operating parameters and/or objectives.
[0027] Particles or atomic contaminants can enter the ion beam 104 during ion implantation that, if implanted, can damage or degrade operation of semiconductor devices formed on the one or more work pieces. The particles or atomic contaminants arise for a variety of sources during ion implantation. For example, carbon can be generated from apertures and other surfaces within the acceleration structure 114 . Typically, the carbon particles are generated by ion beam striking carbon based surfaces such as graphite, which is a commonly used material within ion implantation systems. Additionally, sputtering processes and other deposition mechanisms can release unwanted carbon particles. Additionally, photoresist material, which is commonly used as a mask for ion implantation typically, contains carbon, which can then be released during ion implantation. Although carbon is provided as an example of a type of particle or contaminant, contamination from other materials or types of particles or contaminants is contemplated by the present invention.
[0028] A gas insertion system 122 is also included within the end station 118 and inserts a gas, such as a reactive or atmospheric gas, that mitigates contamination of the one or more work pieces during ion implantation. The gas reacts with contaminants or particles within the ion beam 104 in order to reduce contamination. The gas can react with the contaminants in by a number of mechanisms to reduce contamination of the work pieces and remove the particles or atomic contaminants from the ion beam 104 .
[0029] In one mechanism, the gas can form a passivation layer on a top surface of a target semiconductor devices formed on the one or more work pieces by interacting with the ion beam 104 . The passivation layer 104 can reduce contaminants from passing through to underlying layers and/or mitigate out diffusion of dopants during later fabrication steps. The passivation layer can be comprised of, for example, oxide, nitride, and the like and can be formed by an ion beam enhanced formation process. The passivation layer is formed by a process that is facilitated by the ion implantation and the presence of the reactive gas. For example, an ion beam destroys at least some of the surface bonds of silicon, which results in the silicon having a higher probability of forming an oxide. Then, by supplying an oxygen or water vapor containing gas during the ion implantation, oxide is more readily formed as a passivation layer. The passivation layer can then act as a diffusion barrier to mitigate out diffusion during later fabrication steps.
[0030] Another mechanism to reduce contamination is by employing a gas for consuming contaminants, such as carbon, that would otherwise be absorbed on the surface and driven into the material by the ion beam. The gas or components within the gas can react with the contaminants and form compounds that do not get implanted and/or can be swept away. For example, formation of volatile compounds or gaseous compounds, CO for example, can be readily pumped away or removed by a high vacuum system. This reduces or removes contaminants or particles that could be driven into target semiconductor devices.
[0031] Referring initially to FIG. 2 , an ion implantation process modification system 200 is described in accordance with an aspect of the present invention. The system 200 modifies a current ion implantation process by introducing atmospheric and/or reactive gases during the ion implantation process for the modification and control of material properties resulting from the ion implantation process. The system 200 can be employed, for example, with single wafer ion implantation systems, batch ion implantation systems, plasma immersion ion implantation systems and the like.
[0032] The system 200 includes a gas source/supply 202 , a controller 204 , a gas analyzer 206 , a controllable valve 210 , and a process chamber. The gas source/supply 202 is a mechanism that controllably delivers a gas, such as atmospheric or reactive gas, to the process chamber 212 through a controllable valve 210 . The gas is comprised of one or more individual atmospheric and/or reactive gases. The gas source/supply 202 , in one example, is comprised of one or more gas cylinders, an evaporation or sublimation system, and/or atmospheric inlet (not shown). The gas cylinder contains a reactive gas or vapor at a pressure high enough to provide a required gas flow via the controllable valve 210 to the process chamber 212 . The evaporating system is comprised of water or any other liquid or solid material to generate a reactive gas vapor. In another example, the gas source/supply 202 comprises a source reservoir containing a reactive material in liquid or solid form capable of being evaporated or sublimated at a pressure sufficient to provide the gas. The valve 210 comprises one or more individual valves for selecting flow rate and composition of the reactive gas ultimately provided to the process chamber. The valve 210 is controlled by the controller 204 , which adjusts the flow rate and composition of the reactive gas in order to facilitate removal of contaminants or particles and to mitigate contamination of a target semiconductor device (not shown) within the process chamber 212 .
[0033] The process chamber 212 is part of an end station of an ion implantation system, which can be a single wafer and/or batch ion implantation system. The process chamber 212 holds or supports one or more target devices, such as target wafers, for ion implantation. An ion beam, generated as part of the ion implantation system, enters the process chamber 212 and implants dopants within the ion beam into the target device(s). Typically, the ion beam and/or the process chamber include undesired particles or contaminants that result in contamination of the target devices, as described above.
[0034] The reactive gas enters the process chamber 212 via the valve 210 and interacts with the ion beam to mitigate contamination of the target device(s) by the particles or contaminants. The reactive gas employed is selected according to a type or composition of expected particles or contaminants. Some examples of suitable gases that can be employed include atmospheric gases, such as oxygen, nitrogen, water vapor, and the like. However, other reactant gases can also be employed. The gas can react with the contaminants in by a number of mechanisms to reduce contamination, such as combining with the contaminants and becoming volatile and then removed by vacuum pumping and/or creating a surface condition that prevents or mitigates particles from being implanted beyond or about the created surface condition.
[0035] As one example of a suitable mechanism, the gas can form a passivation layer on a top surface of a target semiconductor device by interacting with the ion beam. The passivation layer can be formed by an ion beam enhanced formation process. For example, ions or dopants within the ion beam can increase the propensity of surface silicon to react with one or more materials within the reactive gas, thereby forming the passivation layer as a result. The passivation layer can then act as a diffusion barrier to mitigate out diffusion during later fabrication steps and may mitigate particles or contaminants from being implanted into the target device(s). Surface reactions with previously deposited material or contaminants may be modified or enhanced as well.
[0036] Another example of a suitable mechanism to reduce contamination is by employing the reactive gas for consuming particles or contaminants, such as carbon, that would otherwise be absorbed on the surface and driven into the material by the ion beam. The gas or components within the gas can react with the contaminants and form compounds that do not get implanted and/or can be swept away. For example, formation of volatile compounds or gaseous compounds can be readily pumped away or removed by a high vacuum system. This reduces or removes contaminants or particles that could be driven into target semiconductor device(s).
[0037] The gas analyzer 206 is a residual gas analyzer that analyzes background gases present within the ion implantation chamber 212 . The gas analyzer 206 generates feedback or a feedback signal for the controller 204 to adjust or control the flow rate of the reactive gases or rate of introduction and/or the reactive gas composition so as to facilitate removal of the contaminants or particles from the ion beam and/or target surface. It is noted that alternate aspects can omit employment of the gas analyzer 206 and still be in accordance with the present invention.
[0038] The controller 204 initially sets the reactive gas composition and flow rate according to process conditions, such as expected contaminant compositions and amount during a particular ion implantation process. The controller 204 adjusts the gas source 202 to supply the reactive gas and adjusts the valve 210 to control flow rate and/or composition of the reactive gas. The controller 204 receives and analyzes the generated feedback from the gas analyzer 206 during ion implantation and determines whether or not corrective adjustments are required. The controller 204 can then perform the corrective adjustments that facilitate removal of contaminants and mitigate contamination, such as by adjusting the reactive gas composition and/or by adjusting the flow rate of the reactive gas to obtain a desired pressure within the process chamber 212 .
[0039] FIG. 3 is a block diagram depicting an interior of a process chamber 300 during an ion implantation process in which a gas, such as a reactive or atmospheric gas, is introduced to mitigate contamination in accordance with an aspect of the present invention. This diagram is presented to further illustrate interaction of the reactive gas with contaminants during ion implantation and is not intended to limit the invention to particular structures or arrangements.
[0040] The process chamber 300 includes a target device support structure 302 that supports a target wafer 304 . The structure 302 can be a process disk for a batch ion implantation system or a single wafer holder for a single wafer ion implantation system. The target wafer 304 is undergoing an ion implantation process, such as one implanting p-type or n-type dopants to form active regions. The target wafer 304 can be at one of a number of stages of fabrication.
[0041] A gas inlet or valve 306 controllably supplies a gas 310 to be in close proximity to the target wafer 304 . The gas 310 , such as an atmospheric or reactive gas, is typically supplied about or near a surface of the target wafer 304 wherein the ion beam 308 is in contact, in this example. The inlet 306 can control the amount or flow rate of the reactive gas 310 and may, in some aspects, control or adjust composition of the reactive gas. The ion beam 308 comprises selected dopants or ions to be implanted and has a beam energy and current density in order to obtain a desired depth and/or concentration for implant on the target wafer 304 . Generally, the ion beam 308 or surrounding portions of the process chamber 300 include unwanted particles or atomic contaminants. The gas 310 can mitigate contamination of the target wafer 304 by a number of mechanisms. One such mechanism is for the gas 310 to combine with the particles or contaminants to form compounds, which are then removed from the process chamber by, for example, a vacuum pump. Another mechanism is to form a passivation layer by an ion beam enhanced formation process that may also mitigate contamination of the target wafer 304 and also serves to facilitate diffusion during later fabrication processes. Other mechanisms that employ the gas 310 to mitigate contamination are also contemplated.
[0042] FIG. 4 is a diagram of an ion implantation process modification system 400 in accordance with an aspect of the present invention. The system 400 is provided for exemplary purposes and modifies a current ion implantation process by introducing atmospheric and/or reactive gases during the ion implantation process for the modification and control of material properties resulting from the ion implantation process. The system 400 can be employed, for example, with single wafer ion implantation systems, batch ion implantation systems, plasma immersion ion implantation systems and the like.
[0043] The system 400 includes a gas source or cylinder 404 , a process chamber 402 , and a chamber vacuum pump 416 . The gas source or cylinder 404 is a mechanism that controllably delivers gas, such as reactive or atmospheric gas, to the process chamber 402 through a controllable valve 408 . A gas source, such as a reservoir, or cylinder valve 406 is employed to control and/or adjust operation of the gas source or cylinder 404 . A flow mechanism 418 , such as a teflon line, connects the source valve 412 with a process chamber valve 408 and also with the gas source valve 406 .
[0044] The process chamber valve 408 comprises one or more individual valves for selecting flow rate and composition of the gas ultimately provided to the process chamber. The valve 408 may be controlled by an external controller (not shown) or can be otherwise adjusted. The chamber valve 408 is generally set to adjust the flow rate and/or composition of the gas in order to facilitate removal of contaminants or particles and/or to mitigate contamination of a target semiconductor device (not shown) within the process chamber 402 .
[0045] The process chamber 402 is part of an end station of an ion implantation system, which can be a single wafer and/or batch ion implantation system. The process chamber 402 holds or supports one or more target devices, such as target wafers, for ion implantation. An ion beam, generated as part of the ion implantation system, enters the process chamber 402 and implants dopants within the ion beam into the target device(s). Typically, the ion beam and/or the process chamber include undesired particles or contaminants that result in contamination of the target devices, as described above.
[0046] The vacuum chamber pump 416 is connected to the process chamber 402 via a vacuum line 420 and removes air/gas from the process chamber 402 in order to obtain a selected or desired atmospheric pressure and to remove gases from the chamber 402 .
[0047] The gas enters the process chamber 402 via the chamber valve 408 and interacts with the ion beam to mitigate contamination of the target device(s) by the particles or atomic contaminants. The gas can react with the contaminants in or about the target device by a number of mechanisms to reduce contamination, such as those described above, or modify the surface of the target.
[0048] The chamber residual gas that can comprise at least a portion of the undesired particles or contaminants is then removed from the chamber by the vacuum pump 416 through the vacuum line 420 .
[0049] FIG. 5 is a flow diagram depicting a method 500 for mitigating contamination of a target device by contaminants during ion implantation by introducing a gas, such as a reactive or atmospheric gas, near a surface of the target device in accordance with an aspect of the present invention. The method 500 can be employed in single and/or batch ion implantation systems.
[0050] It is appreciated that the method 500 , as well as variations thereof, can be further appreciated with reference to other figures of the present invention. Additionally, the method 500 and description thereof can also be employed to facilitate a better understanding of other aspects of the invention described above.
[0051] While, for purposes of simplicity of explanation, the method 500 is depicted and described as executing serially, it is to be understood and appreciated that the present invention is not limited by the illustrated order, as some aspects could, in accordance with the present invention, occur in different orders and/or concurrently with other aspects from that depicted and described herein. Moreover, not all illustrated features may be required to implement a methodology in accordance with an aspect the present invention.
[0052] The method 500 begins at block 502 wherein an ion beam that may comprise contaminants is provided. The ion beam is provided, typically as part of an ion implantation system comprising an ion source, mass analyzer, and a beam line assembly. The ion beam undesirably can comprise contaminants, such as carbon contaminants, that could damage and/or alter a target device without interaction by a reactive gas. The contaminants can be introduced into the beam at various stages of the ion implantation system. The ion beam comprises one or more selected dopants at a selected energy with a selected beam current.
[0053] A gas, such as an atmospheric or reactive gas, composition and flow rate are selected at block 504 according to process characteristics, such as expected contaminants. For example, a gas composition comprising oxygen or water vapor can be suitable for expected carbon contaminants. The flow rate is selected to obtain a desired pressure within the process chamber and permit interaction of the reactive gas and the contaminants.
[0054] The gas is generated at block 506 according to the selected composition and/or flow rate. In one example, one or more gas sources and/or reservoirs can be present as well as a gas cylinder, evaporating system, and/or atmospheric inlet that comprise potential source gases. The gas cylinder contains a gas or vapor at a pressure high enough to provide a required gas flow to the process chamber through the controllable valve. The evaporating system is comprised of water or any other liquid or solid material to generate a reactive gas vapor. One or more valves can be employed to facilitate selection of composition and to also adjust the flow rate.
[0055] The gas is directed toward an implant target location at block 508 . Tube(s), line(s) and/or hose(s) comprised of suitable materials can be employed to carry the reactive gas from gas source(s) to the process chamber. An inlet or valve within or a part of the process chamber can be employed to direct the reactive gas proximate to the implant target location of the target device, wherein the ion beam is impacting that target location.
[0056] The gas reacts with the contaminants and/or mitigates contamination of the target location at block 510 . The gas can, in one example, combine with the contaminants and become volatile. Subsequently, the volatile compounds are removed by pumping. In another example, the gas creates a surface condition, such as a passivation layer, that prevents or mitigates particles from being implanted beyond or about the created surface condition.
[0057] FIG. 6 is a flow diagram depicting a method 600 for mitigating contamination of a target device by contaminants during ion implantation by introducing a gas, such as a reactive or atmospheric gas, near a surface of the target device in accordance with an aspect of the present invention. The method 600 can be employed in single and/or batch ion implantation systems.
[0058] It is appreciated that the method 600 , as well as variations thereof, can be further appreciated with reference to other figures of the present invention. Additionally, the method 600 and description thereof can also be employed to facilitate a better understanding of other aspects of the invention described above.
[0059] While, for purposes of simplicity of explanation, the method 600 is depicted and described as executing serially, it is to be understood and appreciated that the present invention is not limited by the illustrated order, as some aspects could, in accordance with the present invention, occur in different orders and/or concurrently with other aspects from that depicted and described herein. Moreover, not all illustrated features may be required to implement a methodology in accordance with an aspect the present invention.
[0060] The method 600 begins at block 602 wherein an ion beam that may comprise contaminants is provided. The ion beam may comprise contaminants, such as carbon contaminants, that could damage and/or alter a target device without interaction by a reactive gas. These contaminants can be introduced at various stages of an ion implantation system that provides the ion beam. The ion beam comprises one or more selected dopants at a selected energy and dose.
[0061] An initial gas composition and flow rate are selected at block 604 according to process characteristics, such as expected contaminants. For example, a gas composition comprising oxygen or water vapor can be suitable for expected carbon contaminants. The flow rate is selected to obtain a desired pressure within the process chamber, permit interaction of the reactive gas and the contaminants, and remove volatile gases comprising the contaminants.
[0062] The gas is generated at block 606 according to the selected composition and/or flow rate. One or more gas sources can be presented as a gas cylinder, evaporating system, and/or atmospheric inlet that comprise potential source gases. The gas cylinder contains a reactive gas or vapor at a pressure high enough to provide a required gas flow to the process chamber through the controllable valve. The evaporating system is comprised of water or any other liquid or solid material to generate a reactive gas vapor. One or more valves can be employed to facilitate selection of composition and to also adjust the flow rate.
[0063] The gas is directed toward an implant target location at block 608 . Tube(s), line(s) and/or hose(s) comprised of suitable materials can be employed to carry the gas from gas source(s) to the process chamber. An inlet or valve within or a part of the process chamber can be employed to direct the gas proximate to the implant target location of the target device, wherein the ion beam is impacting that target location.
[0064] The gas reacts with the contaminants and/or mitigates contamination of the target location at block 610 . The gas can, in one example, combine with the contaminants and become volatile. Subsequently, the volatile compounds are removed, for example, by pumping. In another example, the reactive gas creates a surface condition, such as a passivation layer, that prevents or mitigates particles from being implanted beyond or about the created surface condition.
[0065] Gaseous partial pressures and composition are measured within the chamber at block 612 . A reactive gas analyzer is typically employed to measure the composition of the air/gas within the chamber. The measurements can include contaminants present, total partial pressure or vacuum, reactive gas present, and the like.
[0066] If the measurements are outside of an acceptable range at block 614 , corrective adjustments for flow rate and composition of the gas are determined at block 616 . Additionally, the corrective adjustments can include a flow rate of exhaust gas from the process chamber.
[0067] Then, the gas composition and flow rate corrective adjustments are applied at block 618 . Typically, the gas source and one or more controllable valves are employed to obtain the corrective adjustments. Subsequently, the method 600 returns to block 612 wherein new measurements are obtained.
[0068] Although the invention has been illustrated and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described components (assemblies, devices, circuits, systems, etc.), the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Additionally, the term “exemplary” is intended to indicate an example and not to indicate superior or best. Furthermore, to the extent that the terms “including”, “includes”, “having”, “has”, “with”, or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.” | A contamination mitigation or surface modification system for ion implantation processes includes a gas source, a controller, a valve, and a process chamber. The gas source provides delivery of a gas, be it atmospheric or reactive, to the valve and is controlled by the controller. The valve is located on or about the process chamber and controllably adjusts flow rate and/or composition of the gas to the process chamber. The process chamber holds a target device, such as a target wafer and permits interaction of the gas with an ion beam to mitigate contamination of the target wafer and/or to modify the existing properties of the processing environment or target device to change a physical or chemical state or characteristic thereof. The controller selects and adjusts composition of the gas and flow rate according to contaminants present within the ion beam, or lack thereof, as well total or partial pressure analysis. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention concerns a turbocharger of the type set forth in the precharacterizing portion of claim 1.
[0003] 2. Description of the Related Art
[0004] In turbomachinery in which the turbine is intended to drive a compressor or the like, it is often desirable to control the flow of motive gas to the turbine to improve its efficiency or operational range. In order to accomplish this, the nozzle passages leading to the turbine wheel may be of variable geometry. These variable geometry nozzle passages can be provided by means of a plurality of blades which are pivotable so as to alter the configuration of the passages therebetween. The design of the suspension system used in association with the pivoting blade design is critical to prevent binding of either the suspension system or the blades.
[0005] U.S. Pat. Nos. 2,860,827 and 4,179,247 disclose designs to prevent binding of the pivoting blade actuation mechanism. However, none of the above-mentioned designs are suspension systems for an actuation system which accommodates the thermal cycling experienced by the turbine housing as well as the components of the actuation system.
[0006] U.S. Pat. No. 2,860,827, the content of which is to be considered as incorporated by reference herein, describes a turbocharger with variable turbine geometry. Exhaust gasses flow radially past nozzles in a ring-shaped passage situated between the housing part of the turbine housing and the nozzle ring, which nozzles are defined by the intermediate space between nozzle blades which are arranged in a ring and mounted pivotably along the nozzle ring, and operate in such a manner that the nozzles are maximally opened when the nozzle blades are radial, and maximally closed when the nozzle blades are essentially oriented tangential.
[0007] The nozzle blades are mounted to the nozzle ring by means of pins, which extend through the nozzle ring, and which carry actuating arms on their opposite ends.
[0008] Provided on the same plane as the circularly arranged actuating arms there is a second ring, the so-called actuating ring, for simultaneous actuation of all actuating arms, for which the actuating ring on its inner edge includes engagement means which cooperate with corresponding engagement means on each of the actuating arms, so that with limited coaxial pivoting of the actuating ring with respect to the nozzle ring all actuating arms, and the therewith associated nozzle blades, can be pivoted.
[0009] Associated with the actuating ring is an actuating means which extends through the turbine housing in order to control the actuating ring from outside the housing.
[0010] The actuating ring is carried by a certain number of rollers each of which is provided with a groove, and guided for limited rotation, which rollers can be arranged in a circular pattern corresponding to the inner edge of the actuating ring.
[0011] These rollers can rotate freely about pins, which pins can be provided in the same part of the turbine housing as the above described actuating means.
[0012] The pins extend through the wall of the turbine housing and are axially fixed directly outside and inside this wall freely rotatably by means of spring rings.
[0013] This arrangement functions in satisfactory manner as long as no great temperature oscillations occur.
[0014] Turbochargers are however subjected to very strong temperature oscillations as a result of the flowing through of hot exhaust gasses through the turbine part, so that the turbine part and adjacent parts are heated up to 900° C.
[0015] These frequently extreme temperature oscillations, together with the extremely high rotation speed of the turbine wheel and the compressor wheel, produce extreme stresses for all components, which results in an early expenditure and loss of function of the turbocharger.
[0016] It is particularly important that the geometric configuration of all cooperating parts, such as nozzle ring, actuating ring, rollers and pins, etc. remain intact, without thermal misalignment and hysteresis.
[0017] The turbocharger according to U.S. Pat. No. 2,860,827 is not optimally designed in order to maintain the geometry of the described parts in the case of large thermal oscillations.
[0018] U.S. Pat. No. 4,179,247 describes a turbocharger and in particular a suspension mechanism for the actuating ring, which is in the form of a double ball bearing.
[0019] This type of ball bearing is particularly critical in the above-mentioned conditions and is beyond this very complicated in its construction.
[0020] Many attempts have been made in order to solve the above described problem, and in part these problems were solved by the turbocharger according to European Patent 0 226 444 (U.S. Pat. No. 4,804,316).
[0021] This patent describes a suspension mechanism for the actuating ring with pins and rollers, the rollers having circumferential grooves, which can carry and guide the actuating ring in a manner similar to that of U.S. Pat. No. 2,860,827.
[0022] In EP-0226444 the roller pins are however not fixed axially in the housing, but rather they extend freely between bores in the housing on one side to bores in the nozzle ring on the other side, wherein a certain separation is maintained between the inner side of the housing and the opposing side of the nozzle ring in order to produce a second ring gap, and wherein the grooved rollers are provided for free rotation on the pins within this second ring gap.
[0023] Since the ends of the pins engage in the nozzle ring, the effect is to provide an exact co-axiality of nozzle ring and actuating ring.
[0024] In practice however two problems are associated therewith.
[0025] On the one hand the construction of the actuating mechanism according to U.S. Pat. No. 2,860,827 is complicated, and the introduction of the roller pins in the bores first in the nozzle ring or the housing, thereafter the seating of the rollers upon the pins and the actuating ring upon the rollers and then the introduction of the free ends of the pins into the bores in the respective other element (housing or nozzle ring) element is very difficult to accomplish without an exact, axially parallel arrangement of these free ends of the pins.
[0026] This is a true test of finesse, since the orientation of the bores between the two elements is never perfect, and besides this, because of the necessary tolerance between pin and bore, the pins tend to be tilted or askew prior to introduction into the second element.
[0027] On the other hand the bores in the housing and those in the nozzle ring are subjected to different thermal dilations, so that in operation the pins are directed away from their exact axially parallel orientation, which detracts from the friction free operation of the parts.
SUMMARY OF THE INVENTION
[0028] The present invention solves the described problems and disadvantages of the state of the art and provides a turbocharger which exhibits the characteristics according to the characterizing portion of claim 1.
[0029] Further tasks and advantages of the invention are seen from the dependent claims.
[0030] It is thus for example one of the tasks of the invention to provide an improved actuating system for a turbine with variable nozzle geometry. It is a further task of the invention to construct an actuating system, in which the actuating ring and the nozzle ring remain precisely coaxial in operation.
[0031] It is further a task to provide a reliable actuating system.
[0032] Finally, it is task to provide a nozzle ring which remains continuously oriented relative to the turbine side wall, in order to produce a ring shaped gap with constant spacing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] In the following the invention will be described in greater detail on the basis of the figures. Therein:
[0034] FIGS. 1 - 6 show different views of a turbocharger according to the state of the art,
[0035] [0035]FIG. 7 is a view according to FIG. 5 having a first embodiment of the present invention integrated therein,
[0036] [0036]FIG. 8 is likewise a view according to FIG. 5, with a second embodiment of the present invention integrated therein,
[0037] [0037]FIG. 9 is a view according to FIG. 3, with a first embodiment of the present invention integrated therein, and
[0038] [0038]FIG. 10 is a view according to FIG. 3, with a second embodiment of the present invention integrated therein.
DETAILED DESCRIPTION OF THE INVENTION
[0039] An engine system as shown in the FIGS. 1 to 3 includes turbomachinery in the form of a turbocharger 10 generally comprising a turbine wheel 12 and a compressor impeller 13 mounted on opposite ends of a common shaft 16 . The turbine wheel 12 is disposed within a turbine housing 18 which includes an inlet 20 for receiving exhaust gas from an engine 14 and an outlet 21 for discharging the exhaust gas. The turbine housing 18 guides the engine exhaust gas into communication with and expansion through the turbine wheel 12 for rotatably driving the turbine wheel. Such driving of the turbine wheel simultaneously and rotatably drives the compressor impeller 13 which is carried within a compressor housing 22 . The compressor housing 22 , including an inlet 23 and outlet 25 and the compressor impeller 13 cooperate to draw in and compress ambient air for supply to the intake of the engine 14 .
[0040] The turbine housing 18 is mounted to a flange member 24 which, in turn, is mounted to center housing 26 and could be a part of it. The compressor housing 22 is mounted on the other side of the center housing 26 . The center housing 26 includes a bearing means 29 for rotatably receiving and supporting the shaft 16 . A thrust bearing assembly 33 is carried about the shaft adjacent the compressor housing for preventing axial excursions of the shaft 16 . A heat shield 44 is positioned about the shaft 16 at the turbine end in order to insulate the center housing 26 from the harmful effects of the exhaust gas.
[0041] Lubricant such as engine oil or the like is supplied via the center housing 26 to the journal bearing means 29 and to the thrust bearing assembly 33 . A lubricant inlet port 37 is formed in the center housing 26 and is adapted for connection to a suitable source of lubricant such as filtered engine oil. The port communicates with a network of internal supply passages which are formed in the center housing 26 to direct the lubricant to the appropriate bearings. The lubricant circulated to the bearings is collected in a suitable sump or drain for passage to appropriate filtering, cooling, and recirculation equipment, all in a well-known manner.
[0042] [0042]FIG. 3 shows the turbine housing 18 forms a generally scroll-shaped volute 28 which accepts the exhaust gas from the engine 14 and directs it onto the blades of the turbine wheel 12 through an annular passage 30 . Thereafter, the exhaust gas flows axially through the turbine shroud 32 and exits the turbocharger through outlet 21 either into a suitable pollution-control device or the atmosphere. Placed within the annular passage way 30 are a plurality of pivotable blades 34 which operate to vary the geometry of the annular passage 30 to control the angle at which the exhaust gas impacts the blades of the turbine wheel 12 . This in turn controls the amount of energy imparted to the compressor wheel and ultimately the amount of air supplied to the engine.
[0043] The flange member 24 and the turbine housing 18 form between them a cavity 27 which houses the hardware used in conjunction with the variable geometry turbine to be described below. The annular passage 30 for the exhaust gas is defined between the inner side wall 31 of the turbine housing 18 and an annular nozzle ring 38 . Located circumferentially around and within the annular passage 30 are a plurality of blades 34 . Each blade 34 is mounted to be capable of pivoting on the nozzle ring 38 on a blade pin 36 which can turn in a bore in the nozzle ring. Attached by welding to the outer end of each blade pin is a blade arm 46 , the shape of which can best be seen in FIG. 6. The nozzle ring is between the blades and the blade arms.
[0044] Located within passage 30 are a plurality of spacers 86 . As shown in FIGS. 4 and 6, spacers 86 are located at the periphery of the plurality of blades. They have an axial length (within the range of 0.005 to 0.015 cm) longer than the blade length. The spacers are press fitted in bores formed in the nozzle ring 38 , though other methods could be used.
[0045] An annular actuating ring 48 has a plurality of slots 51 on its inner radial surface, each of which receives a blade arm 46 . At the inner periphery of the actuating ring 48 are located at least three circumferentially spaced rollers 49 . Rollers 49 are rotatably mounted on pins 55 radially inwardly of the actuating ring and with respective ends inserted in bores in the flange member 24 and the nozzle ring 38 . Pins 55 have some axial clearance within these bores in order to allow nozzle ring 38 slight axial movement. Rollers 49 include an annular groove 59 therearound for acceptance of the inner periphery of the actuating ring 48 . Pins 55 and rollers 49 could be provided additionally at the periphery of the actuating ring 48 if so desired. The pins not only provide a mounting for the actuating ring; they also hold and concentrically locate the nozzle ring 38 and prevent it from rotating.
[0046] The rollers 49 provide for ease of rotation of the actuating ring 48 relative to the flange member 24 and together with pins 55 ensure the concentricity between actuating ring 48 and nozzle ring 38 . The shape of the blade arms 46 as seen in FIG. 6 must be such as to maintain basically a rolling action within slots 51 to avoid binding within actuating ring 48 as it rotates to pivot blades 34 .
[0047] The flange member 24 includes a recessed portion for acceptance of the actuation system as will be described below. Formed in flange member 24 is a shoulder 72 which acts in cooperation with belleville spring 40 . The inboard side of the radially outer edge of spring 40 rests against the shoulder 72 , and when assembled, the opposite side of the radially inner edge of the spring acts against the shoulder portion 39 of the nozzle ring 38 such that it loads the nozzle ring 38 and the spacers 86 against the turbine side wall 31 . Shoulder 72 is continuous about flange 24 with the exception of a break to make room for the bell crank system defined below.
[0048] A tube member 42 which is generally cylindrically shaped with an annular bend therein, is slidably engageable within the inner radial surface of the nozzle ring 38 . The tube member 42 acts as a seal in the event that any exhaust gas leaks behind the nozzle ring 38 and into the cavity 27 formed between the flange 24 and the turbine housing 18 , thereby sealing the turbine housing 18 from the center housing 26 .
[0049] In order to rotate the actuating ring 48 between its two extreme positions which correspond to the limits of the geometry of the annular passage 30 , a bell crank system is used. A pin 50 is rigidly connected to a first linkage member 54 at one end thereof. The pin 50 fits within a corresponding slot 92 within the actuating ring 48 in order to transmit any movement in the bell crank to the actuating ring 48 . The first linkage member 54 is rigidly connected at its other end to a rod member 56 . The rod 56 projects through a bore 57 in the flange member 24 to a point outside the turbocharger assembly. Bushing 58 is used in association with rod 56 . The rod 56 is rigidly connected at its other end to a second linkage member 60 which in turn is connected to an actuator 90 , shown in FIG. 1. The actuator shown is a vacuum boost type which is well known in the art. Furthermore, it is envisioned that other actuator means can be used to control the movement of the blades.
[0050] During operation, movement of the second linkage member 60 is translated into movement of the first linkage member 54 via rod 56 . The existence of pin 50 will translate any movement of the linkage member 54 into rotational movement of actuating ring 48 . In turn, blade arms 46 roll against the side wall of slots 51 to pivot blades 34 while nozzle ring 38 remains stationary. Thus, there is a change in the geometry of the plurality of passageways formed between adjacent blades.
[0051] An alternative embodiment of the invention is shown in FIGS. 5 and 6. FIG. 5 is a partial sectional view of the nozzle and actuating rings, 38 and 48 , respectively.
[0052] In the alternative embodiment the nozzle ring 38 is attached to the turbine housing 18 and defines with it the annular passageway 30 . Specifically, the nozzle ring 38 is bolted directly to the turbine housing 18 by a ring of bolts 60 .
[0053] The blades are mounted on the nozzle ring 38 by blade pins 36 , which can turn in bores in the nozzle ring and are attached at one end to the blades and at the other end to a blade arm 46 . Arm 46 is attached to blade pin 36 by any suitable method of attachment such that the nozzle ring 38 is located between the blade 34 and the blade arm 46 .
[0054] [0054]FIG. 6 shows that actuating ring 48 is an annular ring with a plurality of slots 51 on its inner radial surface. Each slot receives the outer end of a blade arm 46 . Located at the internal periphery of the actuating ring 48 are at least three spaced rollers 49 . Rollers 49 are rotatably mounted on pins 55 spaced radially inwardly of the actuating ring and secured between the nozzle ring 38 and center housing 26 , each of which has bores for acceptance and location of the pins. Rollers 49 include an annular groove 59 therearound for acceptance and guidance of the inner periphery of the actuating ring. Rollers 49 and pins 55 ensure the concentricity between the actuating ring 48 and nozzle ring 38 .
[0055] The alternative embodiment has eliminated several elements of the preferred embodiment, i.e. the flange member 24 and tube member 42 . Center housing 26 is different in that it includes a radially outwardly extending flange portion 27 having a bore 57 therethrough for acceptance of the actuation system. Furthermore, the flange portion 27 includes shoulder 35 shaped to mate with the turbine housing 18 and an annular land 47 above the central bore.
[0056] As shown in FIG. 5, an annular disc 45 is positioned about the turbocharger shaft such that its radially inner edge rests against the land 47 and its radially outer edge rests against a shoulder 39 formed on the inner periphery of nozzle ring 38 . Disc 45 functions as a heat shield and seal to prevent heat and exhaust gas leakage around nozzle ring 38 .
[0057] [0057]FIGS. 7 and 8 show the suspension mechanism according to the present invention in two different embodiments.
[0058] Just as in FIG. 5, in which the same reference numbers designate the same parts as in FIGS. 7 and 8, the nozzle ring 138 carries on its outer edge and in circular arrangement a number of pins 55 ′ (in FIG. 7) and 55 ″ (in FIG. 8), at least however three thereof, distributed about the circumference of the nozzle ring, which pins carry rollers 49 with a groove 59 . The inner edge of the actuation ring 48 is received in these grooves 59 and is guided thereby.
[0059] These pins 55 ′ are seated freely in bores 55 b in the nozzle ring and the portion of the pin extending out of these bores has a length which corresponds essentially to the axial length of the rollers 49 , so that the free pin end practically aligns with the appropriate axial surface of the respective roller, without engaging in any other bores, for example in the housing.
[0060] At least one end of the pin can be tapered or rounded.
[0061] The two disadvantages of EP-0226444 are therewith overcome. On the one hand the assembly of the turbocharger is substantially simplified, since no pins independent of the rollers exist and since the axial extensions of the rollers need to be introduced respectively in only one bore, namely in the nozzle ring, without the necessity of having other ends having to be introduced into some other, more or less axially oriented bore in the housing, and on the other hand, since the rollers are not in a non-defined manner disoriented by the different thermal expansion of the housing and the nozzle ring, which in the state of the art disturbs the axial orientation of the pins and rollers, since the pins engage in only one bore, the geometry of the actuating ring, the nozzle ring and the guide rollers remains established independent of the temperature oscillations.
[0062] An alternative manner FIG. 8 shows an embodiment in which the pins 55 ″ likewise engage in only respectively one bore 55 a , which bore is however provided in the housing 26 , without the other end of the pin engaging in the nozzle ring.
[0063] In this manner the same advantages are achieved as with the embodiment according to FIG. 7 with respect to the simplified assembly since the pins and rollers as well as the actuating ring and the nozzle ring can first be assembled with the housing part 26 , before the housing part is matted to the turbine housing 18 . Here also it is avoided, that the free ends of the pins need be inserted in more or less aligned bores.
[0064] The described effect of the temperature oscillations is likewise unimpaired since there is no longer any necessity to maintain alignment of orientation of boreholes in two different thermally cycling parts.
[0065] [0065]FIGS. 9 and 10 show the inventive turbocharger and in particular a suspension mechanism for the actuating ring according to a first embodiment of EP-0226444, wherein the same reference numbers designate the same parts as in FIG. 3.
[0066] The length of the pins is such that the pin segment extending from the bore exhibits the same length as the axial length of the roller 49 , so that the free end of the pin practically aligns with the appropriate axial surface of the roller.
[0067] Numerous modifications of the described embodiments of the invention would occur to the person of ordinary skill. The present description should thus be considered as exemplary and in no way should be considered to limit the scope of protection of the present invention. This scope of protection should be determined only by the definition of the invention in the following claims, together with their equivalents.
[0068] Thus, for example, the housing part in which the bores 55 a are incorporated in the second embodiment of the invention, could be a part independent of the turbine housing and thus a construction component to be mounted to the turbine housing, or could together with the turbine housing form a unitary part. | A turbocharger with an improved suspension mechanism for the actuation ring of a variable nozzle mechanism, for improved maintenance of the geometry of the suspension mechanism in the case of higher temperature oscillations. The suspension mechanism includes a number of guide rollers ( 48 ) provided between a housing part ( 24, 26 ) and nozzle ring ( 38 ) with circumferential grooves ( 59 ) in which the inner circumference of the actuating ring rides. The rollers are freely rotatable on pins ( 55′, 55″ ), and these pins are inserted in bores ( 55 a or 55 b ) either in a housing part ( 24, 26 ) or in the nozzle ring ( 38 ), but not both. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a locking system for desks, cabinets or other articles of furniture. More particularly, it relates to an adjustable linkage system connecting a primary and a secondary locking means for simultaneously locking and unlocking a plurality of drawers. Such mechanisms are also used as locks for doors located in pedestals or the like. The term primary locking means refers to the mechanism which is directly operated by a key lock and which therefore is the prime mover of the overall locking system. The term secondary locking means refers to the mechanism which actually locks the door or drawers to be locked. Some systems are designed so that one or more secondary means can be connected by separate linkage means to a single, primary locking means. By multiplying secondary means, one can use the same basic system for one or two pedestal desks, three or four compartment credenzas, and so on.
One problem encountered in such locking systems is that of adjustment of the linkage assembly to insure proper coordination between the primary and secondary locking means. One type of linkage assembly system used in the prior art to connect primary and secondary locking means includes an actuator rod having a U-shaped deviation therein which is made of a material which can readily be bent through the use of a pliers or other comparable implement. Thus, one can increase or shorten the length of the linkage rod by changing the bend in the deviation. More specifically, by pinching the legs of the U-shaped deviation inwardly towards one another, one can shorten the effective length of the linkage rod. Contrawise, one can increase the effective length of the linkage rod by prying the legs of the U-shaped deviation away from one another. Pliers can be used for the pinching and for the spreading or a screwdriver might be useable for the spreading. The U-shaped deviation is carried by a bracket for support. The bracket has an opening to provide acess to the U-shaped deviation. Thus, the use of tools is required and adjustment is limited to size of the U-shaped deviation.
SUMMARY OF THE INVENTION
In the present invention the actuator linkage rod is coupled to a secondary locking means and is adjustably joined to a moveable member of primary locking means by an adjustable spring clip. The spring clip couples transmission of movement from the primary locking means to the secondary locking means. By moving the spring clip along the moveable member, the effective length of the linkage rod is readily adjusted.
The use of a spring clip in accordance with this invention is advantageous because of increased simplicity and greater flexibility at fabrication, installation and operation. First, the use of tools is eliminated and the adjustment of the spring clip to change the effective length of the linkage can be accomplished manually. Second, a greater latitude of adjustability is provided. That is, adjustment of the spring clip is not limited as is the size of the U-shaped deviation. Third, adjustment can be made more precisely by relative movement of the spring clip and the linkage. The deformation of a U-shaped deviation results in some return to the original configuration of the deviation because of the resilency of the material. Compensation by deforming more than is actually required is difficult to judge.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a pedestal desk and locking system in accordance with an embodiment of this invention;
FIG. 2 is a front elevation view of the center lock of a locking system in accordance with an embodiment of this invention;
FIG. 3 is a top plan view of the spring clip joining the linkage to the primary lock system;
FIG. 4 is a side elevation view of the spring clip joining the linkage to the primary lock system;
FIG. 5 is a front elevation view of a spring clip in accordance with the embodiment of this invention;
FIG. 6 is a top plan view of a locking system in accordance with the embodiment of this invention; and
FIG. 7 is a front perspective view of the spring clip joining the linkage to the primary lock system.
FIG. 8 is an enlarged view of inset VIII shown in FIG. 6.
DETAILED DESCRIPTION
Referring to the drawings (FIG. 1), a locking system 20 has a primary locking system 17 coupled to a secondary locking system 11 in each desk pedestal 2 by an actuator linkage rod 15. Primary locking system 17 includes moveable rods 18 or as sometimes referred to herein, lock rods 18, to which linkage rods 15 are connected by spring clips 20. Spring clip 20 is made of a flat, elongated resilient material and has a general semi-circular or V-shape (FIG. 3). Spring clip 20 is bent to define a generally cylindrical portion 22 at the base of the "V," which serves as a means for securing spring clip 20 to linkage rod 15. Linkage rod 15 extends up into cylindrical portion 22 and is trapped and firmly held therein. However, during operation of locking system 10, linkage rod 15 rotates with respect to cylindrical portion 22.
A pair of legs 24 extend generally laterally and outward from cylindrical portion 22 and are bent to define three leg parts, 24a, 24b and 24c (FIG. 3). Portions 24a extend immediately from cylindrical portion 22, almost directly laterally, and serve as spacers to provide sufficient spread to legs 24 so spring clip 20 can be easily flexed. Portions 24b extend from portions 24a, generally diagonally across the path of locking rod 18. Finally end portions 24c are bent further inwardly towards one another from their junctions with portions 24b, almost extending perpendicular to rod 18 and parallel to one another. Portions 24c serve as thumb and finger grips for squeezing clip 20, as will be more fully explained herein below. A pair of opposed openings 21a and 21b, one in each diagonal portion 24b of leg 24 of spring clip 20 are aligned to engage lock rod 18 which is part of primary locking system 17. Openings 21a and 21b are formed slightly larger than the lateral cross sectional area of lock rod 18 (FIG. 4) so when legs 24 are pinched inward, toward each other, lock rod 18 can be moved through the holes. Holding the flanges in allows spring clip 20 to slide back and forth on lock rod 18 for infinite adjustment. When the flanges are released, spring clip 20 will lock in place along lock rod 18.
Secondary locking system 11 includes a vertical lock bar 12 having transversely extended lock tabs 13 for engaging lock catches 19 thereby preventing drawer 25 from being pulled out and angle flange 16 extending outwardly from vertical lock bar 12 and coupled to actuator linkage rod 15 to transmit a rotational motion to vertical lock bar 12 (FIGS. 1 and 6). Primary locking system 17 includes a lock cylinder 26 for receiving a key 34 and turning in cooperation with key 34 (FIGS. 1 and 2). Lock cylinder 26 is coupled to a lock cam 27 which has an opening 28 for receiving lock rod 18. Accordingly, rotational movement of key 34 is transmitted to longitudinal motion of lock rod 18. If desired, lock cam 27 can have additional openings (28') for connection to another lock rod (18') such as would be required when a single primary locking system controls two secondary locking systems in opposite directions. FIG. 1 shows such second primary locking systems (11 and 11') and a second lock rods (18 and 18').
Spring clip 20 is supported by a bracket 30 coupled to the component, such as a desk, to be locked (FIG. 7). Bracket 30 is generally a hollow rectangular box with an elongated opening 31 at the side for allowing entry of actuator linkage rod 15 and an elongated opening 32 in the top for allowing angled end 33 of actuator linkage rod 15 to protrude above bracket 30. Spring clip 20 is positioned so cylindrical area 22 is longitudinally aligned with angled end 33 and is spring biased toward it. Spring clip 20 is rotationally oriented so openings 21a and 21b are aligned to receive lock rod 18. Pressing the flanges of spring clip 20 toward each other brings openings 21a and 21b into position so lock rod 18 can easily pass. In an embodiment in accordance with this invention, spring clip 20 can have an additional pair of opposed openings 23a and 23b, one in each flange of spring clip 20 to accommodate any variations in the relative displacement of lock rod 18 from actuator linkage rod 15. Such displacement could occur when a single lock rod 18 is used to actuate a plurality of spaced actuator linkage rods 15. That is, lock rod 18 would have a gradual downward slope from lock cam 27. Although adjustment of spring clip 20 along angled end 33 of actuator linkage rod 15 is possible to accommodate for such differences, it is preferable to have the entire longitudinal length of cylindrical area 22 in contct with angled end 33.
OPERATION
One can lock drawer 25 by rotating vertical lock bar 12 so lock tabs 13 are moved into the path of lock catchers 19. Accordingly, a first position (unlocked) of lock tab 13 permits passage of lock catch 19 (FIG. 1) and a second (locked) position of lock tab 13 engages lock catches 19. In order to achieve proper adjustment of locking system 10, so that lock bar 12 does not lock drawer 25 when it is not supposed to and so that it is in a locking position when lock cylinder 26 has been rotated to a point where one can remove the key, one can simply adjust the effective length of actuator linkage rod 15 and lock rod 18. Advantageously, when the lock tabs 13 are in a lock position, lock rod 18 is adjusted for maximum travel through openings 21a and 21b of spring clip 20. If there are a plurality of spring clips 20 along the length of lock rod 18 then a similar adjustment is made for all spring clips 20. As a result of this adjustment, the effective length of the connection from lock rod 18 to secondary locking system 11 has been adjusted. During adjustment, spring clip 20 moves longitudinally with respect to lock rod 18 and permits rotational movement of angled end 33 of linkage rod 15 with respect to cylindrical portion 22. During movement for locking or unlocking, there is no relative movement between lock rod 18 and spring clip 20 but there is relative rotational movement between spring clip 20 and linkage rod 15.
Such an adjustment of a locking system 10 is typically necassary because of manufacturing tolerances in the fabrication of linkage rods, locking bars and locking mechanisms. Now such variations due to manufacturing tolerances can be accurately compensated for without the use of tools. Further, lock rod 18 can be made in several uniform lengths because minor variations can be compensated for by sliding spring clip 20 along lock rod 18. Such standardization is advantageous because it reduces cost. Further, the assembly and adjustment of the linkages has been accomplished without the use of any welding. A typical spring clip 20 is rolled and then has openings 21 and 23 punched. A typical material for spring clip 20 is spring steel. Secondary locking system 11 may also include an embodiment where a swinging credenza door is locked. Typically, for example, actuator linkage rod 15 is then coupled to a lever which swings to engage a hook coupled to a door.
Various modifications will no doubt occur to those skilled in the art to which this invention pertains. For example, the particular separation of the legs of the spring clip and the shape of the openings may be varied from that disclosed herein. These and all other variations which basically rely on the teachings by which this disclosure has advanced the art are properly considered within the scope of this invention. | The specification discloses a locking system for locking a plurality of drawers or like components in desk pedestals or like components having a primary and secondary locking means movable between a first position unlocking said components and a second position locking said components, and an adjustable linkage operably connecting the primary locking means to the secondary locking means. The linkage system includes two rods adjustably connected to each other by a spring clip whereby the effective length of the linkage assembly can be varied and the first and second positions of the secondary locking means thereby adjusted. The spring clip engages a linkage rod so there is a bias force against the linkage rod preventing movement of the rod relative to the spring clip. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates to a liquid level and other height measurements, more specifically, to an electromagnetic method and apparatus for measuring liquid level for different liquids (conducting and non-conducting) and also for measuring clearance or thickness.
BACKGROUND OF THE INVENTION
[0002] The usefulness of the RF or microwave field application for monitoring of liquid level is recognized by the prior art. Such devices can operate with either RF or microwave excitation. When an electromagnetic field is excited in the container partially filed with liquid, parameters of the electromagnetic field, such as resonant frequency, vary with the level of the liquid. In particular the state of the art is shown in V. A. Viktorov “Microwave Method of Level Measurement”, The Resonance Method of the Level Measurement, Moscow: Energija. 1987, disclosing an electrodynamic element, made as section of a long line, inserted into a monitored container where the resonant frequency is measured.
[0003] A general discussion, see Viktorov V. A., Lunkin B. V., Sovlukov A. S. “Method of and Apparatus for Level Measurement by Hybrid Electromagnetic Oscillation Excitation”, Radio-Wave Measurements, Moscow: Energoatomizdat, 1989, states that an electrodynamic element is placed in a monitored container, and the element's resonance frequency has a direct correlation to the level of the liquid within the container.
[0004] Slowed electromagnetic waves and slow-wave structures are also well known in the field of microwave engineering, see J. R. Pierce, “Traveling-Wave Tubes” D. Van Nostrand Company, Inc., Princeton, N.J., 1950. These waves are electromagnetic waves propagating in one direction with a phase velocity ν p that is smaller than the light velocity c in a vacuum. The relation c/ν p is named slowing or deceleration and is designated as n. In the most practically interesting cases, slowed electromagnetic waves are formed in slow-wave structures by coiling one or two conductors (for example, into a helix, as it is shown in FIG. 1 (prior art), where the other conductor is a cylinder), which increases the path length traveled by the wave, or by successively connecting resonant elements or cells, energy exchange between which delays the phase of the wave, or by using an electrodynamically dense medium (usually a dielectric), or a combination of these methods. Additional deceleration was also obtained due to positive electric and magnetic coupling in coupled slow-wave structures, see V. V. Annenkov, Yu. N. Pchelnikov “Sensitive Elements Based on Slow-Wave Structures” Measurenient Techniques , Vol. 38, # 12, 1995, pp. 1369-1375.
[0005] The slow-wave structure-based sensitive elements are known in the art, see Yu. N. Pchelnikov, I. A. Uvarov and S. I. Ryabtsev, “Instrument for detecting Bubbles in a Flowing Liquid”, Measurement Techniqies, Vol. 22, # 5, 1995, pp.559-560, and Yu N. Pchelnikov, “Possibility of Using a Cylindrical Helix to Monitor the Continuity of Media”, Measurement Techniques , Vol. 38, # 10, 1995, pp.1182-1184. The slowing of the electromagnetic wave leads to a reduction in the resonant dimensions of the sensitive elements and this enables one, by using the advantages of electrodynamic structures, to operate at relatively low frequencies, which are more convenient for generation and are more convenient for primary conversion of the information signal, but sufficiently large to provide high accuracy and high speed of response. The low electromagnetic losses at relatively low frequencies (a few to tens of megahertz) also helps to increase the accuracy and sensitivity of the measurements. The slowing of the electromagnetic wave leads also to energy concentration in the transverse and longitudinal directions, that results in an increase in sensitivity, proportional to the slowing down factor n. See V. V. Annenkov, Yu. N. Pchelnikov “Sensitive Elements Based on Slow-Wave Structures” Measurement Techniques , Vol. 38, # 12, 1995, pp. 1369-1375.
[0006] Most slow-wave structures were made as two-conductor periodic transmission lines (see Dean A. Watkins “Topics in Electromagnetic Theory”, John Willy & Sons, Inc. Publishers). A version is possible when a slow-wave structure contains three or more different conductors. In all cases the slowed wave is excited in the electrodynamic element between different combinations of the two conductors. The coiled conductors increasing the wave path are named “impedance conductors”, and conductors with simple configuration such as rods, tapes, etc., stretched along the wave propagation direction are named “screen conductors”, see V. V. Annenkov, Yu. N. Pchelnikov “Sensitive Elements Based on Slow-Wave Structures” Measurement Techniques , Vol. 38, # 12, 1995, pp. 1369-1375.
[0007] Both the prior art and the present invention measure one or more parameters of an electromagnetic field. Some of the prior art methods and present invention use an electrodynamic element, some are made as a resonant cavity filled with measured liquid or made as an electrodynamic element placed in or outside a container. The electrodynamic element is connected to an external RF or microwave signal generator which is used to excite an electromagnetic field. The change in, for example, the level of the liquid, causes a shift in the characteristics of the electromagnetic field in the electrodynamic element. The shift in characteristics correlates to a change, for example, in the level of the liquid within the measured container.
[0008] Devices used in the prior art exhibit several problems overcome by the present invention. Previous methods depend upon the sensitivity of a measured parameter of an electromagnetic field to measure level displacement and provide signal resolution. Sensitivity and resolution increase with frequency. However, the increase in frequency is accompanied by an increase in electromagnetic losses, such losses causing a loss of accuracy of the measurement. Besides, it is known that the higher frequency is, the higher is the cost of an electronics. The relatively low accuracy realized from the prior art is also due to resonant frequency dependence on the monitored liquid's electric parameters. Thus, there is a need in the art for an electromagnetic method and apparatus for monitoring liquid levels and other heights measurements that has better sensitivity, better resolution, greater diversity and lower cost.
SUMMARY OF THE INVENTION
[0009] The present invention employs slow-wave structures in electrodynamic elements Contrary to the capacitance and inductance sensitive elements, slow-wave structure-based sensitive elements are electrodynamic elements and can be characterized by the electrodynamic parameters such as resonant frequencies, Q-factor or attenuation, phase shift, etc. The main advantages of such “sensitive electrodynamic elements”, in comparison to known ones, are: concentration of electromagnetic energy in a small volume, the independence of their electrodynamic parameters upon the electronic circuit parameters and the dependence on the monitored liquid level or the measured height.
[0010] Frequency decrease is achieved due to slowing. Sensitivity increase is achieved due to electromagnetic energy concentration near the surface of the level to be measured and due to splitting electric and magnetic fields for the monitored volume. The measured parameters range is widened due to wide frequency band of slow-wave structures. The application convenience is due to possibility of placing of the electrodynamic element outside the monitoring level. The slow-wave structure-based electrodynamic elements are designed, as a rule, on dielectric base, stable to temperature alteration and its resonant frequency dependence on temperature is very small, contrary to, for example, cavity resonators.
[0011] The present invention teaches an electromagnetic method of measuring the liquid level and other heights or other measurements that require high resolution wherein an excited electromagnetic wave with a preset distribution of the electric and magnetic components of the electromagnetic field makes it possible to increase the sensitivity and accuracy of measurement of the level, using relatively low frequencies. The method is implemented in an apparatus, for example, for measuring liquid level, wherein the structural form of the electrodynamic element, used as the sensing element allows increased sensitivity and accuracy. In the invention an electrodynamic element is made at least one section of a slow-wave structure.
[0012] It is known, that the dielectric or conducting materials, placed in the electromagnetic field, alter its parameters, for example, its velocity, that leads to the phase delay or resonant frequency alteration. The degree of such alteration and, therefore, sensitivity S is proportional to the relation of the volume V of a material to the monitored volume V 0 , for example, a volume of a resonator, and depends on the electric and magnetic field distribution in the monitored volume
S˜ ( V/V 0 ) F ( e, m, s )ƒ
[0013] where here ε and μ are relative permittivity and permeability, σ is conductivity of a material, F(ε, μ, σ) is some function, depending on the material position in the monitored volume V, and ƒ is frequency and the sign means proportionality. See V. A. Viktorov, B. V. Lunkin and A. S. Sovlukov, “Radio-Wave measurements” Moscow: Energoatomizdat, 1989, p. 27. If, for example, dielectric material is monitored, it should be placed in the electric field and its effect will be proportional to the electric field energy in the material. Since the resonant volume V 0 is smaller when the first resonant frequency ƒ 1 is higher, the sensitivity S rises with frequency increasing. Slowing of an electromagnetic wave n times leads to an n times decrease of the resonant volume V 0 , that is accomplished by the sensitivity n-times increasing
S˜ ( V/V 0 ) n F (ε, μ, σ)ƒ 1
[0014] The sensitivity increasing permits lower frequency and works with smaller losses, which, for example, in conductors are proportional to the square root of frequency. See: E. C. Young “The Penguin Dictionary of Electronics”, second edition, Penguin Books, p. 530. The electromagnetic losses decrease leads to resolution increase.
[0015] When resonant frequency of a metal container, filed with liquid, is measured, the resonant frequency depends not on the liquids level only; it depends on temperature also since the liquid's permittivity and the container's volume change with temperature change. The slow-wave structure-based electrodynamic elements are designed, as a rule, on dielectric base and its resonant frequency depends on temperature very small.
DESCRIPTIONS OF THE DRAWINGS
[0016] For further understanding of the nature and objects of the present invention, reference should be had to the following figures in which like parts are given like reference numerals and wherein:
[0017] [0017]FIG. 1 illustrates a slow-wave structure of the prior art, coiling one conductor into helix, the other conductor is a cylinder;
[0018] [0018]FIG. 2 illustrates a preferred embodiment of the present invention in which the electrodynamic element is placed inside a container and in the fluid to be measured;
[0019] [0019]FIG. 3 is an illustration of the preferred embodiment of the present invention showing the electrodynamic element placed inside the container but not contacting the fluid to be measured;
[0020] [0020]FIG. 4 shows a preferred embodiment of the present invention in which the electrodynamic element is placed outside the container holding the fluid in one configuration;
[0021] [0021]FIG. 5 shows a preferred embodiment of the present invention showing the electrodynamic element is placed outside the container holding the fluid in one configuration;
[0022] [0022]FIG. 6 illustrates the measuring circuit of the preferred embodiment of the present invention;
[0023] [0023]FIG. 7 illustrates a second measuring circuit of the preferred embodiment of the present invention;
[0024] [0024]FIG. 8 is an illustration of the electrodynamic element of the preferred embodiment of the present invention;
[0025] [0025]FIG. 9 is a graph of the electric and magnetic fields near the plane electrodynamic element of the preferred embodiment of the present invention;
[0026] [0026]FIG. 10 is a graph of the electric and magnetic fields inside and outside the cylindrical electrodynamic element of the preferred embodiment of the present invention;
[0027] [0027]FIG. 11 illustrates a two-conductor slow-wave structure with an impedance conductor and a screen conductor, showing the field of the preferred embodiment of the present invention;
[0028] [0028]FIG. 12 shows a two-conductor slow-wave structure with an impedance conductor and a screen conductor using oppositely directed radial spirals;
[0029] [0029]FIG. 13 illustrates the electric field concentration between conductors and outside conductors in an in-phase type wave in the electrodynamic element of the preferred embodiment of the present invention;
[0030] [0030]FIG. 14 illustrates an anti-phase type wave electric and magnetic fields distribution in the electrodynamic element of the preferred embodiment of the present invention;
[0031] [0031]FIG. 15 shows a bifilar helix;
[0032] [0032]FIG. 16 illustrates interdigital combs;
[0033] [0033]FIG. 17 illustrates the coupled meander-lines of the preferred embodiment of the present invention;
[0034] [0034]FIG. 18 illustrates a bifilar helix with a screen conductor made as a rod illustrating the electric field penetration through the fluid;
[0035] [0035]FIG. 19 illustrates a bifilar helix with a screen conductor made as a rod illustrating the electric field is concentrated near the helix;
[0036] [0036]FIG. 20 illustrates the preferred circuit of the attenuation measurement of the preferred embodiment of the present invention;
[0037] [0037]FIG. 21 illustrates the preferred circuit of the preferred embodiment of the present invention for phase delay measurement;
[0038] [0038]FIG. 22 illustrates a preferred circuit of the preferred embodiment sharing conversion to generator frequency alteration;
[0039] [0039]FIG. 23 illustrates the preferred circuit of the preferred embodiment of the present invention to cause alteration of the resonant frequency;
[0040] [0040]FIG. 24 illustrates impedance and screen conductors;
[0041] [0041]FIG. 25 illustrates an additional slow-wave structure 53 in the electrodynamic element, terminated to an inductor 58 having a big induction;
[0042] [0042]FIG. 26 illustrates an electrodynamic element wherein an additional slow-wave structure is replaced by two inductors;
[0043] [0043]FIG. 27 illustrates an additional slow-wave structure 53 in the electrodynamic element terminated to a capacitor, having a big capacitance;
[0044] [0044]FIG. 28 illustrates an electrodynamic element wherein an additional slow-wave structure is replaced by two capacitors;
[0045] [0045]FIG. 29 illustrates varying the distance between conductors of a slow-wave structure;
[0046] [0046]FIG. 30 illustrates a varying screen conductor width;
[0047] [0047]FIG. 31 illustrates a bifilar helix wound on a dielectric tube with a screen conductor as a rod;
[0048] [0048]FIG. 32 illustrates a zigzag slow-wave structure installed on a dielectric container wall;
[0049] [0049]FIG. 33 illustrates a slow-wave structure having interdigital combs with inclined fingers;
[0050] [0050]FIG. 34 illustrates a slow-wave structure with an inclined combination of interdigital combs;
[0051] [0051]FIG. 35 illustrates an arithmetic spiral for the impedance conductor;
[0052] [0052]FIG. 36 illustrates a logarithmic spiral for impedance conductor;
[0053] [0053]FIG. 37 illustrates a graph showing the resonant frequency of the electrodynamic element dependence upon water level in a container;
[0054] [0054]FIG. 38 illustrates frequency dependence of the electrodynamic element including bifilar helix upon the water level in a container.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0055] As shown in FIGS. 2 - 5 , an electrodynamic element 1 may be placed inside (FIGS. 2 and 3) or outside (FIGS. 4 and 5) a container 2 , filed with liquid 3 , or other material. An element 1 can be placed into container 2 at an angle 90° or at an angle other than 90°, as shown in FIG. 2. An element 1 is connected to the measuring circuit 4 , comprising (FIGS. 6 and 7) a generator 5 of electromagnetic oscillations at RF frequency, primary transducer 6 , converting the electromagnetic parameters of the electrodynamic element 1 into an electromagnetic informative signal, for example, phase delay, frequency, power attenuation, etc., and converter 7 , converting electromagnetic informative signals into information about a liquid level, height, etc. The electromagnetic element 1 can be connected to the generator 5 with one end, in parallel, as it is shown in FIG. 6, or can be connected with both ends, in series, between generator 5 and transducer 6 , as it is shown in FIG. 7.
[0056] At least one slowed electromagnetic wave is exited in the electrodynamic element 1 at a frequency at which the electromagnetic field penetrates into liquid 3 . The region 8 formed between the surface 9 of the liquid 3 and the roof 10 , becomes the monitored volume inside container 2 . If the container 2 is made from metal, electrodynamic element 1 must be placed inside container 2 , as it is shown in FIGS. 2 and 3. If it is made from dielectric or has a dielectric roof or has a dielectric window, the electrodynamic element 1 can be placed outside container 2 , as it is shown in the FIGS. 4 and 5. In all mentioned cases the electromagnetic field excited in the electrodynamic element 1 penetrates into the monitored region, e.g. liquid 3 and region 8 , that is, the distance δ between the electrodynamic element 1 and liquid 3 must not exceed the thickness of an “aria of the energy concentration” which is approximately equal to λ/2πn, where λ is a wave-length in vacuum. In FIG. 2 it can be a thickness of a protective covering on the electrodynamic element 1 (not shown in Figures), in FIG. 3 it is the region 8 height, in FIG. 4 it is the container 2 wall thickness, in FIG. 5 it is the roof 10 thickness plus the region 8 height. The sensor may be used at an angle other than 90°.
[0057] The electrodynamic element 1 comprises slow-wave structure 11 (FIG. 8), one end of which is connected to the input 12 and the other end—to the output 13 , the last two being included in the electrodynamic element 1 . Depending on the quantity (number) of slow-wave structure 11 conductors (impedance conductors 14 , 15 and a screen conductor 16 in FIG. 8), the input 12 and the output 13 have two or more poles connected with slow-wave structure 11 . For example, as it is shown in FIG. 8, the poles 17 , 18 are connected to the opposite ends of impedance conductor 14 , the poles 19 , 20 are connected to the opposite ends of the other impedance conductor 15 , the poles 21 and 22 are connected to the opposite ends of the screen conductor 16 .
[0058] One or more types of slowed waves at one or different frequencies can be excited in such element simultaneously, their number being equal to the number of conductors minus one. See Le Blond A., Mourier G. “L'etude des Lignes a bareux a structure periodique pour les tubes electroniques U.H.F.” Ann. Radioelektr., 1954, 9, # 38, p. 311 or Z. I. Taranenko, Ya. K. Trochimenko “Slow-Wave Structures” Kiev, 1965, p.57.
[0059] The excited slowed electromagnetic wave in the electrodynamic element 1 propagates along this element crossing the liquid's surface 9 as it is shown in FIGS. 2 and 4, or not crossing it, as it is shown in FIGS. 3 and 5. In both cases electric parameters of the liquid 3 , or another material have an effect on the slowing n of the wave, that leads to alteration of electromagnetic parameters of the electrodynamic element 1 . The difference is that in the first case the range of the monitored level l is near to the height h of the electrodynamic element 1 , in the second case it is much smaller and can not exceed the area of slowed wave energy concentration λ/2πn.
[0060] Any electromagnetic wave is characterized by so called “wave coefficient”, defining electric and magnetic fields E and H dependence on time t and coordinate z in the direction of wave propagation:
E,H˜e
jωt+γz
[0061] where w is an angular frequency and γ is a propagation constant, which can be presented by the expression
γ=− j β−α
[0062] Here β is the phase constant (β=ω/ ν p ) , ν p is the phase velocity, α is the attenuation constant, related to the specific attenuation factor K a in decibels /meters by the relation
K a =8.68α
[0063] See V. V. Annenkov, Yu. N. Pchelnikov “Sensitive Elements Based on Slow-Wave Structures” Measurement Techniques , Vol. 38, # 12, 1995, pp. 1369-1375.
[0064] The slowed electromagnetic wave is excited in electrodynamic element 1 with distribution of the electric and magnetic components of the field required for the best sensitivity. Usually, the field distribution is defined by the slowing n and the frequency ƒ Thus, when there is no boundary surface outside the impedance conductor, the longitudinal components of the electric field E z and the magnetic field H z of the wave are proportional to e −xτ′ , e −xτ″ for a plane system (curves 23 and 24 in FIG. 9), and are proportional to modified Bessel functions I 0 (rτ′), I 0 (rτ″) inside of a cylindrical slow-wave structure (curves 25 , 26 in FIG. 10), or K 0 (rτ′), K 0 (rτ″) outside it (curves 27 , 28 ) Here x and r are the coordinates along the normal to the surfaces of the impedance conductors and τ′, τ″ are two different meanings of the transverse constant τ, related to the different slowing values n′, n″ and the wave number k by the relations
(τ′) 2 =k 2 [( n′ ) 2 −1],
(τ″) 2 =k 2 [( n″ ) 2 −1]
k=ω 2 ε 0 μ 0
[0065] where ε 0 and μ 0 are the permittivity and the permeability of the vacuum, respectively. If the frequency changes and slowing n is constant, the wave number has different values, for example, k′, k″ that leads to transverse constant changing also
(τ′) 2 =( k ′) 2 ( n 2 −1)
(τ″) 2 =( k ″) 2 ( n 2 −l )
[0066] In FIGS. 9 and 10 τ″=2τ′.
[0067] It is seen from the expressions for τ′, τ″ and is shown in FIGS. 9 and 10, that a field distribution can be changed as by slowing n change, as by angular frequency ω change also. Thus, one can obtain different distribution of the field in the same electrodynamic element, exciting, for example, two or more slowed waves at different frequencies.
[0068] The field distribution can be changed by the different modes of the slowed wave exciting also. For example, the field distribution in FIG. 10 for bifilar helix was calculated for in-phase excitation. In case of anti-phase excitation the field distribution is defined by Bessel functions of the first order and is quite different from the distribution shown on FIG. 10.
[0069] One of the most important peculiarities of slowed waves is the electric and magnetic field energy splitting between electric and magnetic type waves (E- and H-modes, respectively). See L. N. Loshakov, Yu. N. Pcel'nikov “Theory and the Traveling-Wave Tube Amplification Calculation, M: Sov. Radio, 1964. When the slowing n is sufficiently great, the energy of the electric field of the slowed wave is concentrated mainly in the E-mode, while the energy of magnetic field is concentrated mainly in the H-mode, both modes existing in the slowed wave only together. Because of this the electromagnetic parameters of the monitored medium (the conductivity, the permittivity, and the permeability) have a different effect on the E-modes and H-modes, thus manifesting their own kind of an anisotropy. See Yu. N. Pchel'nikov “Anisotropy of a Semiconductor Film in the Field of a Slow Wave”, Journal of Communications Technology and Electronics, Vol. 39, # 10, 1994, pp. 66-69. This enables one, on the one hand, to make independent measurements , for example, of the electric permittivity and magnetic permeability, while on the other hand it enables one to control the distribution of the electric and magnetic fields across the transverse section of the electrodynamic element 1 . Thus, screening by a screen conductor of the E-mode reduces the amount of the electric-field energy in the measured volume compared with the amount of the magnetic-field energy by more than a factor of n 2 .
[0070] In the simplest cases, the distribution of electric and magnetic fields is as shown in FIGS. 9 and 10 and is formed, for example, by a two-conductor slow-wave structure 11 with an impedance conductor 14 and a screen conductor 16 (FIG. 11). Here an electric (E) field and a magnetic (H) field is distributed between conductors 14 , 16 and outside the impedance conductor 14 . The field distribution can be changed essentially in so called coupled slow-wave structures, which impedance conductors 14 , 15 have configuration of turned through 180°, mirror images of one another, for example, oppositely directed radial spirals, shown in FIG. 12. Electric and magnetic energy can be split in transverse section of such structures and this splitting can be controlled by exciting in-phase or anti-phase types of waves.
[0071] When exciting an in-phase type wave in the electrodynamic element 1 with two coupled impedance conductors 14 , 15 connected to one another, and a screen conductor 16 , the magnetic field energy is concentrated between conductor 14 and conductor 15 (FIG. 13), while an electric field energy is shifted outside conductors 14 , 15 . This can be explained by the different directions of the transverse components of currents in conductors 14 , 15 and by equality of its potentials. The transverse components direction is perpendicular to the direction of the wave propagation.
[0072] In the second case (anti-phase excitation) an electric field energy is concentrated between impedance conductors 14 , 15 (FIG. 14), while a magnetic field energy will be shifted outside conductors 14 , 15 . It can be explained by the transverse components of the currents in conductors 14 , 15 directions coincidence and by the opposite potentials on the conductors 14 , 15 . In this case the screen conductor 16 can be absent.
[0073] The distribution of electric and magnetic components of a slowed electromagnetic wave excited in the electrodynamic element 1 must be chosen depending upon electric parameters of the liquid (material) 3 being monitored. As it was mentioned earlier, the dielectric material's effect is proportional to the electric energy concentrated in the dielectric material 3 . Thus, in the case of dielectric materials with a small conductivity, or nonconductive, the electric component of the slowed electromagnetic wave must be shifted into the monitored volume (in the liquid 3 and the region 8 ), as it is shown in FIG. 13. If a material 3 has dielectric and ferrite properties simultaneously, for example if it is ferrite, both electric and magnetic fields should be shifted in the monitored volume simultaneously or in two different electromagnetic elements 1 .
[0074] If the liquid (material) 3 is conducting, for example a melted metal, the magnetic field will effect oppositely to that of the electric field and the magnetic field should be shifted from monitored volume, as it is shown in FIG. 13 or, alternatively, the electric field should be shifted from the monitored volume, as it is shown in FIG. 14. The current induced on the metal surface by the magnetic field of the electrodynamic element 1 would increase this magnetic field in the region 8 or in the container 2 wall, if the electrodynamic element 1 is installed outside container 2 , as it is shown in FIG. 4.
[0075] If the electrodynamic element I is made as at least hexapole (FIG. 8), in-phase and anti-phase waves can be excited simultaneously, or one after the other. It allows more informative parameters to be obtained. For example, two or more resonant frequencies can be utilized, which would permit excluding from the resultant measurements the influence of temperature and other errors, the number of excluded influences being equal to the informative parameters number minus one See B. N. Petrov, V. A. Viktorov, B. V. Lunkin, A. S. Sovlukov, “Principals of the Invariance in Measurements” Moscow, Nauka, 1976. The number of informative parameters can be increased by exciting one or both types of waves at different frequencies, for example, at the first resonant frequency, second, etc.
[0076] As it was shown earlier, the degree of energy concentration near the electrodynamic element 1 depends on slowing down rate n, and frequency ƒ, and increases as n and ƒ increase. It is true for fields presented by the zero space harmonic. The same effect of energy concentration can be obtained by exciting an E- or H-mode wave, or both, with fields presented by the first (plus one and minus one) space harmonics. See Dean A. Watkins “Topics in Electromagnetic Theory”, New York, John Wiley & Sons, Inc ., p. 2, and Yu. N. Pchelnikov, V. T. Sviridov, “Microwave Electronics” Moscow: Radio-Svjaz, 1983, p. 44.
[0077] When working with the first (plus one and minus one) space harmonics, the depth of the field penetration into the monitored volume (a thickness δ of the energy concentration area) is determined not by the frequency, the slowing, or the conductivity, as it is in the case of zero space harmonic, but it is determined by the period T of the slow-wave structure, and is approximately equal to T/π in symmetrical structures, for example, bifilar helices (FIG. 15), and T/2π in two-stage structures, for example, in interdigital combs (FIG. 16). It follows from this that the field distribution of the first space harmonics is proportional to coefficient exp. (−xπ/ T) or exp. (−2xπ/ T), respectively in plane symmetrical and two-stage structures. In the case of bifilar helix, the field distribution, as mentioned above, is defined by the Bessel functions of the first order.
[0078] In the case of the first space harmonics energy concentration near impedance conductors 14 , 15 is better than in case of zero space harmonic. Such effect of the field concentration can be used at relatively low frequencies for sensitivity increasing. The effective slowing in this case is equal to λ/2T for symmetrical structures and is equal to λ/T for two-stage structures. Thus, the sensitivity is proportional to the next values:
S˜ ( V/V 0 )λ/ 2 T F (ε, μ, σ) ƒ 1
[0079] or
S˜ ( V/V 0 )λ/ T F (ε, μ, σ) ƒ 1
[0080] where λ is a wavelength in the vacuum. Substituting ƒ 1 =c/ λ, where c is the velocity of the light in the vacuum, we obtain
S˜ ( V/V 0 ) c/ 2 TF (ε, μ, σ)
[0081] or
S˜ ( V/ V 0 ) c /TF (ε, μ, σ).
[0082] It is seen, that in the case of the first harmonics sensitivity S does not depend on frequency and increases with period T decreasing.
[0083] In most cases slowed waves are so called hybrid waves, comprising both, E- and H-mode waves, and these waves can be presented by different space harmonics. For example, the E-mode in a meander-line (FIG. 17) is presented on the whole by the zero space harmonic, while the H-mode is presented by the first harmonics. The in-phase type wave in the bifilar helix (FIG. 15) comprises E- and H-modes, which are presented by zero space harmonic; the anti-phase type wave comprises the E- and H-modes both being presented by plus one / minus one harmonics.
[0084] For example, if a bifilar helix (impedance conductors 14 and 15 ) with a screen conductor 16 made as a rod ( FIGS. 18 and 19) is placed into container 2 , filed with a dielectric liquid 3 and in-phase and anti-phase waves simultaneously or one after another are excited, the in-phase wave parameters will depend as upon liquid 3 density (average permittivity) as upon its level l, while the anti-phase wave parameters will depend mainly upon the level l. In the first case the electric field penetrates through the liquid 3 (FIG. 18), in the second case the electric field is concentrated near conductors 14 , 15 (FIG. 19).
[0085] Existence of a certain distance S' between electrodynamic element 1 and the monitored liquid (material) 3 decreases sensitivity S approximately by a factor of exp. (−δτ), decreasing simultaneously an influence of the monitored liquid (material) 3 electric parameters, for example, the permittivity ε, which would cause an alternation on the results of measurements. The electrodynamic analysis of a slow-wave structure's model at relatively big slowing, when n≈τ/k, (see Yu. N. Pchelnikov “Possibility of Using a Cylindrical Helix to Monitor the Continuity of Media”, Measurement Techniques, Vol. 38, # 10, 1995, p.p. 1182-1184) showed, that if parameter δ′τ exceeds 2 and permittivity ε exceeds 9, the effect of the permittivity alteration is very small More accurate calculation allowed to connect a relative error Δl/l of the level measurements with the parameter δ′τ, the permittivity ε relative alteration Δε/ ε, and the relative permittivity ε 1 of the medium between the electrodynamic element 1 and the monitored liquid (material) 3 , for example the container 2 wall,
Δl/l= (ε 1 /ε)( th δ′τ−cth δ′τ)Δε/ε
[0086] where “th” indicates hyperbolic tangent and “cth” indicates hyperbolic cotangent. If, for example, ε 1 /ε=0. 05, δ′τ=1, then 1% dielectric permittivity ε alteration (Δε/ε) leads to a relative error (Δl/l) smaller than 0.0276%.
[0087] The alteration of the monitored liquid (material) 3 electric parameters do not effect the results of the level (height) measurement if a slowing n is relatively small and is approximately equal to the square root of relative permittivity ε of the monitored liquid (material) 3 ,
n≈{square root}{square root over (ε)}
[0088] In this case the transverse constant τ in the monitored dielectric is nearly equal to zero and the monitored material effects on slowing as metal screen, see Yu. N. Pchelnikov “Radiation of Slow Electromagnetic Waves in a magnetic Insulator”, Journal of Communications Technology and Electronics, Scripta Technica, Inc., A Wiley Conipany, Vol. 40, # 6, 1995, p.p. 25-30.
[0089] A variation in level (height) causes a variation of the propagation constant γ due to the effect of the liquid (material) 3 electric parameters depending on the field distribution in the slowed electromagnetic wave. For example, gasoline increases the imaginary part of the propagation constant γ; highly conductive materials, in some cases decrease the imaginary part of γ, some acids will increase both imaginary and real parts, etc.
[0090] The variation of the real part of the propagation constant γ is indicated by the attenuation of the slowed electromagnetic wave in the electrodynamic element 1 . The preferred circuit of the attenuation measurement is shown in FIG. 20. Here the electromagnetic signal from the output 29 of the generator 5 (standard RF generator can be element 1 , slow-wave structure 11 and output 13 , passes through the input 32 of a standard amplitude comparator 33 and is compared with, the signal from the end 34 of the signal divider 31 , connected to the input 35 of the comparator 33 . The results of this comparison in voltage are converted into the level by the converter 7 , which can be standard voltmeter. Other measuring circuits can be used too.
[0091] The variation of the imaginary part of the propagation constant γ is indicated by the phase delay measurement. The preferred circuit is shown in FIG. 21. Here the electromagnetic signal from output 29 of generator 5 passes through end 30 of the signal divider 31 , input 12 of the electrodynamic element 1 , slow-wave structure 11 , output 13 and gets to input 36 of a standard phase comparator 37 with the voltage output, its phase being compared with phase of a signal coming to the input 38 of the comparator 37 from the end 34 of the signal divider 31 . The results of this comparison in voltage are converted into the level by the converter 7 , which can be a standard voltmeter. Other measuring circuits can be used too.
[0092] The variation of the phase delay can be also converted into generator 5 frequency alteration Δƒ. It can be done by the electrodynamic element 1 sequence inserting in the feedback network 39 of amplifier 40 (FIG. 22). Filter circuits 41 and 42 in feedback 39 can be inserted to increase stability of the generator 5 . In this case the generator 5 takes part of the primary transducer 6 , converting a phase delay alteration into the frequency alteration.
[0093] The variation of the imaginary part of the propagation constant γ can be also indicated by the resonance frequencies ƒ 1 of the electrodynamic element 1 variation. If the slow-wave structure 11 is open ended (the end 13 is open),
ƒ 1 =c (2 i− 1)/(4 b·n ),
[0094] where c is the light velocity in the vacuum, i=1, 2, . . . is a resonant frequency number, b is the length of the slow-wave structure 11 , n is a slowing down value.
[0095] If the slow-wave structure 11 is short ended (the end 13 is closed), then
ƒ 1 =ci /(2 b·n ).
[0096] The resonance frequency ƒ 1 can be measured by standard net analyzer or by other devices. If the electrodynamic element 1 includes two-conductor slow-wave structure 11 , for example a bifilar helix, the preferred circuit to convert alteration of resonant frequency to informative parameter is very simple and combine, as it was in the previous example, the generator 5 and transducer 6 (FIG. 23). Here pole 17 of the electrodynamic element 1 is connected to the inverting input 43 of an operational amplifier 44 ; the other pole 19 is connected to the earth (it could be the pole 21 if the other conductor of the slow-wave structure would be screen conductor 16 ). The poles 18 , 20 can be open ended, short ended or terminated. It depends on liquid (material) 3 electric parameters. For example, if it is dielectric, they can be open ended or terminated on a big inductance. Simultaneously, the inverting input 43 is connected through a resistance 45 to the output 46 of amplifier 44 and the non-inverting input 47 is connected through a resistance 48 to the output 46 and is connected through a resistance 49 to the earth, forming a Schmitt trigger (see “The Penguin Dictionary of Electronics”, second edition, p. 505). The signal from the output 46 has meander configuration with frequency near the resonance frequency of the electrodynamic element 1 .
[0097] As discussed above, the apparatus for liquid level measuring comprises an electrodynamic element 1 , connected to a measuring circuit 4 (FIGS. 2 - 5 ), the last including a generator 5 of electromagnetic oscillations, a transducer 6 , connected to a converter 7 , converting an electric signal to indicate the measured parameters, such as liquid level (FIGS. 6 and 7). The electrodynamic element 1 (FIG. 8) includes at least one slow-wave structure 11 , input 12 and output 13 , connected to the ends of the slow-wave structure 11 . The slow-wave structure 11 includes at least one impedance conductor 14 , fashioned as a row of conducting members arranged in series in the direction of the slowed wave propagation (arrow A) and connected to one another with spacing, and a screen conductor 16 , made as a tape, plate, cylinder, etc. For example, impedance conductor 14 in FIG. 24 includes conducting fingers 50 connected one to another in the direction of arrow A by a conducting base 51 with gaps 52 . The screen conductor 16 can be made as a conducting plate.
[0098] Also, as discussed above, slow-wave structure 11 can include two or more impedance conductors ( 14 and 15 in FIG. 8) and, as a rule, one screen conductor 16 . From one end of slow-wave structure 11 all its conductors are connected to the input 12 , each to one pole, for example, impedance conductor 14 in FIG. 8 is connected to the pole 17 , impedance conductor 15 —to the pole 19 and the screen conductor 16 —to the pole 21 . From the other end of the slow-wave structure all its conductors are connected to the output 13 , conductor 14 —to the pole 18 , conductor 15 —to the pole 20 , conductor 16 —to the pole 22 . The input 12 and output 13 can be standard coaxial adapters, or can be made from cable or wires.
[0099] In most cases the electrodynamic element 1 forms a multipole, such as a dipole, quadripole or hexapole element, as it is shown in FIG. 8 (with poles 17 , 19 , 21 from one end and poles 18 , 20 , 22 from the other end).
[0100] In some cases, when the distribution of electric or magnetic field along the slow-wave structure should be homogeneous, a section of slow-wave structure 53 described below (FIGS. 25, 27) should be added in series to the slow-wave structure 11 . If the electrodynamic element 1 is open ended or terminated to an inductor 54 having big inductance, as it is shown in FIG. 25, the slow-wave structure 53 must have the wave impedance (characteristic impedance) Z 1 much bigger than the wave impedance Z 2 of the slow-wave structure 11 . If the electric length (a phase delay φ) in both structures is the same (the preferred case), the first resonance frequency ƒ 1 of the electrodynamic element 1 is defined by the expression (see Yu. N. Pchelnikov, A. A. Elizarov, “Quasiresonators Using Slowing Down Systems” Radioelectronics and Communications Systems , Vol. 34, # 10, 1991, pp. 68-72.)
ƒ 1 =c φ/ 2 πnb
φ≈{square root}{square root over ( Z 2 /Z 1 )}
[0101] where c is the velocity of light in the vacuum, b is the slow-wave structure 11 length, n is slowing in the slow-wave structure 11 . In this case a distribution of the electric-field energy along slow-wave structure 11 is proportional to
cos 2 βz
β z≦φ
[0102] where β is the phase constant in the slow-wave structure 11 , z is the coordinate along the structure 11 . Thus, if the whole phase delay φ is smaller 0.3 (e.g. Z 1 /Z 2 is larger than 9),
cos 2 b z> 0.8.
[0103] This means the electric-field energy decrease along the electrodynamic element 1 is smaller than 20%.
[0104] In the case under consideration the additional slow-wave structure 53 can be replaced by two inductors 55 , 56 with relatively small inductance L 1 and L 2 . (FIG. 26). Though the preferable case is when L 1 =L 2 =Z 2 /πφ, one inductor can be used also.
[0105] If the electrodynamic element 1 is short ended or terminated to a big capacitance 57 , as it is shown in FIG. 27, and homogeneous distribution of the magnetic field energy along slow-wave structure 11 should be obtained, the wave resistance Z 1 of the additional slow-wave structure 53 must be chosen much smaller than the wave resistance Z 2 of the slow-wave structure 11 . In this case, if a phase delay in both slow-wave structures is the same and equal to φ, the magnetic field energy distribution along slow-wave structure 11 is proportional to
Cos 2 βz
[0106] and
φ≈{square root}{square root over ( Z 2 /Z 1 )}
[0107] If φ<0.3, then cos 2 , βz<0.8 and the magnetic field distribution along the electrodynamic element 1 does not alter more than 20%.
[0108] The additional slow-wave structure 53 can be replaced by two capacitors 58 , 59 with relatively big capacitance C 1 and C 2 (FIG. 28) Though the preferable case is when C 1 =C 2 = 1/Z 2 πφ, one capacitor can be used also.
[0109] Commonly, impedance conductors of the slow-wave structure have a constant period T, as it is shown in FIG. 24. The slowing n varies approximately in inverse proportion to T. Changing the slowing n one can change the energy concentration. It follows from this that the T variation along the slow-wave structure 11 can be used for the energy distribution adjustment.
[0110] The energy distribution in the monitored volume can be adjusted also by the variation of the distance d between slow-wave structure 11 conductors, for example, between impedance conductor 14 and the screen conductor 16 , as it is shown in FIG. 29. The distance between conductors 14 and 16 increasing leads to the energy increasing in the area 60 outside the conductor 14 . The same effect can be achieved by the conductor 16 width w altering along the structure 11 , as it is shown in FIG. 30. The width decreasing as the distance increasing is accompanied by a screening decreasing.
[0111] As was stated above, a slow-wave structure can be done with two impedance conductors installed on the same surface one in the other, as it is shown in FIGS. 15 and 16, or installed one opposite the other, as it is shown in FIGS. 12 and 17. In both cases in-phase and anti-phase waves can be excited. This allows one to achieve different distribution of the electric-field and magnetic-field energy in the cross section of the slow-wave structure 11 . The greatest difference in the energy distribution is achieved in the coupled slow-wave structures, for example, radial spirals with opposite directions of winding (FIG. 12) or meander-lines, shifted in the longitudinal direction one to another on the half period, e.g. on T/2 (FIG. 17). It is seen that configuration of such impedance conductors are mirror images of one another turned through 180°.
[0112] If the impedance conductors 14 , 15 are installed outside the container 2 on its wall and anti-phase wave is excited, the energy distribution, as it was shown earlier, is defined by a period T. In this case the thickness of the energy distribution area is equal to T/π in the symmetrical structures (FIG. 19) and to T/2π in the two-stage structures (FIG. 16). It follows from this that the container 2 wall thickness must not exceed T/π in the first case and T/2π in the second case.
[0113] If the container 2 has a relatively small diameter and is made from a dielectric material, the impedance conductors 14 , 15 can be made as two identical helices, forming a two-wire helix. The screen conductor can be made as a rod (FIGS. 18 and 19), that allows one to monitor simultaneously the liquid 3 level and its density, The same structure wound on the dielectric tube 61 (FIG. 31) is convenient for a dielectric liquid 3 monitoring inside the container 2 . In this case a thin dielectric coating 62 can protect conductors 14 and 15 .
[0114] If the container 2 is made from a dielectric material and is relatively large, the slow-wave structure 11 can be installed on the small section of the container 2 on the inner or outer surface of its wall. It can be two identical zigzag-lines, shown in FIG. 32, or interdigital combs, shown in FIGS. 33 and 34. To make the level measurement more uniform the fingers 63 of one comb (conductor 14 ) and the fingers 64 of the other comb (conductor 15 ) must incline so that its bases 65 , 66 must lay in the same horizontal plane, as it is shown in FIGS. 33, 34. In FIG. 33 fingers 63 , 64 are inclined. In FIG. 34 the both combs (conductors 14 , 15 ) are inclined with angle ζ to a vertical in accordance to condition
Sinζ= T/ 2 a
[0115] where T is period of conductors 14 , 15 , α is the length of fingers 63 , 64 .
[0116] If the electrodynamic element 1 is installed in parallel to the liquid surface, the impedance conductor 14 of the slow-wave structure 11 can be made as a radial spiral, for example, an arithmetic spiral (FIG. 35) or logarithmic spiral (FIG. 36), made as metallization on one side of a dielectric substrate 67 . The screen conductor 16 can be made as at least one radial beam on the other side of the substrate 67 .
[0117] The resonance frequency ƒ of the electrodynamic element shown in FIG. 33 dependence upon the water level in a Teflon container 2 is presented in FIG. 37. The small inductors were connected to the conductors 14 , 15 , as it was shown in FIG. 26. Analogous dependence for the electrodynamic element 1 including bifilar slow-wave structure 11 shown in FIG. 31 is presented in FIG. 38.
[0118] Other applications of this method and apparatus may be made, such as measuring rotation, linear displacement thickness of thin films, and medical application. Accordingly, because many varying and different embodiments may be made within the scope of inventive concepts herein taught including equivalent structures of materials hereafter thought of, and because many modifications may be made in the embodiments herein detailed in accordance with descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. | A method and apparatus for monitoring one or more parameters of a variable physical structure, such as liquid level, is disclosed. The method and apparatus includes an electrodynamic element placed in proximity to a monitored structure and exciting within said element an alternating electromagnetic field. The electromagnetic field should be at a frequency at which the electromagnetic field penetrates into the monitored structure and then variations of the electromagnetic field parameters are measured for the element caused by a variation in the structure. The exciting of the electrodynamic element is by an electromagnetic field in the form of at least one slowed electromagnetic wave having suitable energy distribution of the electric and magnetic fields for the measuring of the electromagnetic field parameters. | 6 |
RELATED APPLICATIONS
This application is a divisional of U.S. patent application Ser. No. 12/013,361, filed Jan. 11, 2008, now U.S. Pat. No. 7,617,643, which claims benefit under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 60/957,434, filed Aug. 22, 2007. Each of U.S. patent application Ser. No. 12/013,361 and U.S. Provisional Patent Application No. 60/957,434 is incorporated in its entirety by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This application is directed toward fire-rated wall construction components for use in building construction.
2. Description of the Related Art
Fire-rated wall construction components and assemblies are commonly used in the construction industry. These components and assemblies are aimed at preventing fire, heat, and smoke from leaving one portion of a building or room and entering another, usually through vents, joints in walls, or other openings. The components often incorporate the use of some sort of fire-retardant material which substantially blocks the path of the fire, heat, and smoke for at least some period of time. Intumescent materials work well for this purpose, since they swell and char when exposed to flames, helping to create a barrier to the fire, heat, and smoke.
One example of a fire-rated wall construction component is the Firestik™ design. The Firestik™ design incorporates a metal profile with a layer of intumescent material on its inner surface. The metal profile of the Firestik™ design is independently and rigidly attached to a wall component, such as the bottom of a floor or ceiling, and placed adjacent to other wall components, such as a stud and track. The intumescent material, which is adhered to the inner surface of the metal profile, faces the stud and track, and the space created in between the intumescent material and the stud and track allows for independent vertical movement of the stud in the track when no fire is present.
When temperatures rise, the intumescent material on the Firestik™ product expands rapidly. This expansion creates a barrier which encompasses, or surrounds, the stud and track and substantially prevents fire, heat, and smoke from moving through the spaces around the stud and track and entering an adjacent room for at least some period of time.
While the Firestik™ design serves to prevent fire, heat, and smoke from moving through wall joint openings, it also requires independent attachment and proper spacing from wall components. It would be ideal to have wall components and systems which themselves already incorporate a fire-retardant material.
An additional problem regarding current fire-rated wall components concerns ventilation. Exterior soffits for balconies or walkways are required to be fire rated. However, these soffits need to be vented to prevent the framing members from rotting. The rot is caused when airflow is taken away and condensation forms inside the framing cavity. The moisture from the condensation attacks the framing members and destroys them from the inside out. In many cases, the deterioration is not noticed until the framing is completely destroyed. Therefore, a fire-rated wall component is needed which accommodates proper ventilation during times when no fire or elevated heat is present, and seals itself when fire or elevated heat is present.
SUMMARY OF THE INVENTION
The present invention is directed toward fire-rated wall construction components and systems for use in building construction. The term “wall,” as used herein, is a broad term, and is used in accordance with its ordinary meaning. The term includes, but is not limited to, vertical walls, ceilings, and floors. It is an object of the invention to provide wall components and systems which have fire-retardant characteristics. It is also an object of the invention to provide wall components and systems which allow for needed ventilation during times when no fire or elevated heat is present.
To achieve these objects, the present invention takes two separate components, a wall component and intumescent material, and combines the two for use in building construction. The present invention includes at least one surface on a wall component capable of accepting intumescent material. In some embodiments, the outer surface of the intumescent material sits flush with a second surface of the wall component. This allows the wall component to retain its general shape and geometry without creating unwanted edges, protrusions, or uneven shapes. It also removes the need for a separate product or wall component to be installed outside or adjacent to a stud or track.
In an embodiment which resembles a vent or ventilation system, the intumescent material includes a set of holes. The term “holes,” as used herein, is a broad term, and is used in accordance with its ordinary meaning. The term includes, but is not limited to, holes, mesh, and slots. When the vent is in use, the combination of the holes in the intumescent material and the holes in the vent surface allow for continuous air flow through the vent. The holes need not match up co-axially, as long as air flow is permitted. In some embodiments, the holes in the intumescent material may line up co-axially with the holes in the vent surface. Additionally, in some embodiments a flat strap sits above the intumescent material. The flat strap may be a discrete piece attached separately, or may already be an integral part of the vent itself. The flat strap has its own set of holes which, when in use, allow for continuous air flow through the vent. In some embodiments the holes may be aligned co-axially with both the holes in the vent surface and the holes in the intumescent material. By having three sets of holes, air can flow through the vent, intumescent material, and strap during times when there is no fire or elevated heat. When the temperature rises, however, the intumescent material will expand quickly and block air pathways. In this manner, the entire vent will be sealed, substantially preventing fire, heat, and smoke from reaching other rooms or parts of the building for at least some period of time.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects and advantages of the various devices, systems and methods presented herein are described with reference to drawings of certain embodiments, which are intended to illustrate, but not to limit, such devices, systems, and methods. The drawings include 5 figures. It is to be understood that the attached drawings are for the purpose of illustrating concepts of the embodiments discussed herein and may not be to scale.
FIG. 1 illustrates a cross-sectional view of an embodiment of a fire-rated wall component connected to a floor and stud element.
FIG. 2 illustrates a perspective view of an embodiment of a fire-rated wall component with annular portions.
FIG. 3 illustrates a perspective view of an embodiment of a fire-rated wall component with annular portions, including intumescent material.
FIG. 4 illustrates a perspective view of an embodiment of a fire-rated wall component with slots and intumescent material in the slots.
FIGS. 5A and 5B illustrate perspective views of embodiments of a fire-rated wall component including holes for ventilation.
FIG. 6 illustrates a perspective view of an embodiment of a fire-rated wall component including holes for ventilation.
FIG. 7 illustrates a bottom perspective view of an embodiment of a fire-rated wall component including holes for ventilation.
FIG. 8 illustrates a cross-sectional view of an embodiment of a fire-rated wall component with intumescent material on its top surface.
FIG. 9 illustrates a cross-sectional view of an embodiment of a fire-rated wall component with intumescent material on both its top and side surfaces.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is directed toward fire-rated wall construction components and systems for use in building construction. Fire-rated wall construction components and assemblies are commonly used in the construction industry. These components and assemblies are aimed at preventing fire, heat, and smoke from leaving one portion of a building or room and entering another, usually through vents, joints in walls, or other openings. The components and assemblies often incorporate the use of some sort of fire-retardant material, such as intumescent material, which substantially blocks the path of the fire, heat, and smoke for at least some period of time.
FIG. 1 illustrates a cross-sectional view of an embodiment of a fire-rated wall component 10 connected to a floor or ceiling element 18 and stud element 20 . The wall component 10 is used as a track for holding a stud within a vertical wall, and may include slots along its sides. The slots provide areas for connection with the studs and allow for vertical movement of the attached studs during an earthquake or some other event where vertical movement of the studs is desired.
As can be seen in FIG. 2 , wall component 10 has both a flat top surface 28 and two annular surfaces 24 and 26 . Top surface 28 is flat for ease of attachment to the bottom surface of a floor or ceiling 18 . The two annular surfaces 24 and 26 are designed to receive intumescent material. The intumescent material, identified as 12 and 14 in FIGS. 1 and 3 , is bonded to annular surface 24 and 26 . The term “bonded,” as used herein, is a broad term, and is used in accordance with its ordinary meaning. The term includes, but is not limited to, mechanically bonded or bonded using adhesive. In some embodiments, when the intumescent material is bonded, an outer surface of the intumescent material will be flush with top surface 28 . This allows top surface 28 to remain flush, or at least partially flush, with the bottom of floor element 18 , and may aid in the installation of wall component 10 to a floor or ceiling. This flush attachment additionally allows the wall component 10 to retain a fluid or smooth-shaped geometry free of added edges, overlaps, or protrusions.
By incorporating intumescent material onto a wall component such as a track for studs in the manner shown, it becomes unnecessary to use or attach additional features or devices to the wall component. Instead, when the temperature rises near the wall component 10 , the intumescent material 12 and/or 14 will heat up. At some point when the intumescent material becomes hot enough, it will quickly expand to multiple times its original volume. This intumescent material will expand towards the floor or ceiling element 18 and outwards toward any open space. This helps to substantially prevent fire, heat, and smoke from moving past, through, or around wall component 10 and stud 20 for at least some period of time.
FIG. 4 illustrates another embodiment of a fire-rated wall component 32 . In this embodiment, the wall component 32 again takes the form of a track member for use in holding studs in place within a vertical wall. However, here the wall component 32 has two slots, shown as 34 and 36 , wherein the intumescent material 40 and 42 is attached. As can be seen in the drawing, the top surface layers of intumescent material 40 and 42 are flush with the top surface 38 of wall component 32 . This allows the top surface 38 of wall component 32 to maintain a smooth geometry, which may aid in the installation of wall component 32 to a floor, ceiling or intersecting wall. This flush attachment additionally allows the wall component 10 to retain a fluid or smooth-shaped geometry free of added edges, overlaps, or protrusions. However, a flush attachment as described above is not essential to the success of the present invention.
It is possible that more than two slots could be used in the type of embodiment shown in FIG. 4 , or even as few as one. The purpose of having the intumescent material located in the slots 34 and 36 is to create fire protection areas. When the intumescent material 40 and 42 becomes hot, it will expand rapidly into the open areas around it. Much as in the embodiment shown in FIGS. 1-3 , this expansion will help to create a barrier, or seal, substantially preventing fire, heat, and smoke from moving from one area of a building to another for at least some period of time.
FIGS. 5A and 5B illustrate other embodiments of a fire-rated wall component 46 . Here, the wall component takes the form of a vent. The wall component 46 has a lower ventilation area 48 which includes a set or series of ventilation holes. These holes, which are hidden from view in FIGS. 5A and 5B , but are shown in FIG. 7 , allow air and other matter to travel between floors and rooms in a building, or between the outside of a building and the interior of a building.
As can be seen in FIG. 5A , a strip of intumescent material 50 is attached adjacent to and above ventilation area 48 . The top surface of the intumescent material is flush with the top surface 54 of wall component 46 . This allows for easy installation and use of a flat strap 52 . A flush fit, however, is not essential to the success of the present invention.
The intumescent material 50 has a series of surfaces defining holes. These holes are hidden from view in FIGS. 5A and 5B but are shown in FIG. 6 . The holes allow air and other matter to continue to travel between floors and rooms in a building, or between the outside of a building and the interior of a building. Flat strap 52 also has a series of holes 60 located in its center area. This series of holes, much like the ventilation and intumescent material holes, allows air and other matter to travel between floors and rooms in a building, or between the outside of a building and the interior of a building.
When the intumescent material 50 becomes hot, it will expand rapidly into the open areas around it. Much as in the embodiments shown in FIGS. 1-4 , this expansion will help to create a barrier, or seal, substantially preventing fire, heat, and smoke from moving from one area of a building to another for at least some period of time.
FIG. 6 illustrates another embodiment of a fire-rated wall component 56 . In this view, intumescent material holes 58 are visible, and the intumescent material 50 extends along the sides of vent area 48 . When the intumescent material 50 becomes hot, it expands rapidly, filling much if not all of the space underneath the flat strap 52 . This expansion substantially cuts off any air movement through the vent surface 48 , and substantially prevents fire, heat, and smoke from moving through the vent for at least some period of time. As can be seen in the embodiment in FIG. 6 , the flat strap 52 is formed as an integral part of the wall component 56 . In other embodiments, the flat strap 52 may be a discrete piece attached separately.
FIG. 7 illustrates a bottom view of an embodiment of a fire-rated wall component 66 . Here, ventilation holes 68 can be seen in the vent area 48 . The intumescent material 50 is attached to both the vent area 48 and along its extended sides.
FIG. 8 illustrates another embodiment of a fire-rated wall component 72 . In this embodiment, the wall component 72 resembles a simple track for holding a wall stud 20 beneath a ceiling 18 . Here, the intumescent material 74 is attached to the top surface of the wall component 72 . During installation, it is possible to install the wall component 72 and intumescent material 74 to the ceiling 18 . In some embodiments, this may be accomplished by threading a screw through both the wall component and intumescent material. Additionally, in some embodiments the intumescent material may extend down one or both sides of the wall component 72 .
FIG. 9 illustrates another embodiment of a fire-rated wall component 80 . In this embodiment, the wall component 80 resembles a simple track for holding a wall stud. However, here the intumescent material 84 extends both along a portion of the top and side surfaces of the wall component 80 . In some embodiments, an outer surface of the intumescent material 84 may be flush with the top surface 82 .
The present application does not seek to limit itself to only those embodiments discussed above. Other embodiments resembling tracks, vents, or other wall components are possible as well. Various geometries and designs may be used in the wall components to accommodate the use of fire-retardant material. Additionally, various materials may be used. The wall component material may comprise steel or some other material having at least some structural capacity. The fire-retardant material may comprise intumescent material or some other material which accomplishes the same purposes as those described above. | The present invention is directed toward fire-rated wall construction components for use in building construction. The invention provides wall components and systems which have fire-retardant characteristics, as well as wall components which allow for needed ventilation in a building throughout times when no fire is present. Embodiments include tracks for holding studs which incorporate various geometries capable of receiving intumescent material. When the intumescent material becomes hot, it expands rapidly and fills its surrounding area, blocking fire, heat, and smoke from traveling to other areas of a building. | 4 |
[0001] This application is a divisional application and claims the benefits of U.S. patent application Ser. No. 12/925,574, filed Oct. 25, 2010, hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to the field of pallets and more particularly to accessories for pallets, and even more particularly to accessories that are utilized in association with movement or repositioning of the pallets by forklift trucks or similar devices, for protection of the pallets and/or facilitation of movement, when the pallet is on the ground or support surface.
[0003] It is well known to utilize pallets to enable efficient movement of multiple, heavy or odd-shaped objects, wherein a motorized forklift or handtruck is used to raise the pallet off the ground, the forklifts or handtrucks being wheeled devices. The forklifts or handtrucks possess a pair of forks that extend in parallel for insertion into or beneath a pallet, the forks able to be raised and lowered by motor or hydraulic means. The pallets may be composed of wood, plastic, metal or similar material capable of supporting a load. The pallets typically comprise a deck to directly support the load, the deck being a planar sheet member, a plurality of slat members, or a custom shaped surface to correspond with the particular load or object being supported. The deck is positioned a short distance from the ground surface through the use of legs, side walls, stringers or like members. At least one side of the pallet is provided with a single large fork access opening or a pair of smaller openings to receive the forks of the forklift or handtruck, which are inserted horizontally and extend sufficient distance beneath the deck to allow the pallet to be raised and lowered securely and without excessive tilting. In this manner a loaded pallet may be moved in well known manner from one position to another by inserting the forks into the pallet, relocating the pallet, and then lowering the pallet at the desired location.
[0004] In many instances it is desirable to place the pallet into a relatively confined or specific location, such as when the pallet it being loaded onto a trailer or positioned in a warehouse amidst other pallet, next to a wall, etc. It is often difficult for even skilled operators to accurately position the forklift or handtruck so that when the pallet is lowered it is in the precise location desired. When loading pallets from the ground onto trailers from the rear, the desired final location may be beyond the reach of the forklift. Furthermore, in some instances the forks themselves will extend beyond pallets of small dimension, making it impossible to lower the pallet such that it is abutting another pallet, a wall or like structure. In these circumstances, the forklift or handtruck operator will attempt to reposition the pallet by pushing against the side wall of the pallet with the ends of the forks, or by inserting the forks a small distance into the pallet, raising one side of the pallet slightly to reduce the area of the pallet in contact with the ground surface, then advancing the forklift to slide the pallet into the desired location. With both of these techniques, multiple tries may be required to obtain the desired position. Additionally, these techniques can easily damage the pallets or the load supported by the pallet if great care is not taken.
[0005] It is an object of this invention to address the problems set forth above with regard to repositioning a pallet situated on the ground or support surface into a precise location by providing a device that allows the forklift or handtruck operator to quickly and easily reposition the pallet while minimizing or eliminating the potential of damaging either the pallet or the load. It is a further object to provide such a device that is readily portable and is structured to be universally applicable to all pallet types.
SUMMARY OF THE INVENTION
[0006] The invention is a portable pallet positioning bar that enables the operator of a forklift, handtruck or similar device to easily reposition a loaded pallet into a precise location. The pallet positioning bar comprises an elongated main body having a face member, at least one lifting flange member oriented substantially perpendicularly to the face member and extending rearward, and a pair of fork members extending from the front of the face bar, the fork members capable of insertion into the fork openings found on standard pallets. The lifting flange member may be a single elongated member or a plurality of shorter members. A footer flange member may be provided on the base of the main body, thereby altering the generally L-shaped cross-sectional configuration of the main body to a generally C-shaped configuration in cross-section. A handle for lifting and carrying the device may also be provided. The fork members may each comprise an upper surface member adapted to abut and support the underside of a pallet deck and a runner member having a curved or slanted end to facilitate insertion of the fork members into the pallet and sliding along the ground surface.
[0007] To utilize the pallet positioning bar, the fork members are manually inserted into the fork openings of the pallet to be repositioned, such that the elongated main body abuts the exposed side of the pallet. The forklift or handtruck operator then inserts the tips of the forks of the forklift or handtruck beneath the lifting flange member and abutting the face member of the pallet positioning bar. The forks of the forklift or handtruck are raised slightly to elevate the pallet positioning bar and tilt the near side of the pallet to reduce surface friction, and the forklift or handtruck is then advanced to reposition the pallet, the forks of the forklift or handtruck pushing against the face member of the pallet positioning bar to slide the pallet. When the pallet is properly repositioned, the forks are lowered and removed from the pallet positioning bar, and the pallet positioning bar is manually removed for subsequent use with other pallets.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 a perspective view of an embodiment of the invention.
[0009] FIG. 2 is a side view of the embodiment of FIG. 1 .
[0010] FIG. 3 is a top view of the embodiment of FIG. 1 .
[0011] FIG. 4 is a front view of the embodiment of FIG. 1 .
[0012] FIG. 5 is a rear view of the embodiment of FIG. 1 .
[0013] FIG. 6 is a bottom view of the embodiment of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0014] With reference to the drawings, which depict one embodiment of the pallet positioning bar invention, the invention will now be described in detail with regard for the best mode and preferred embodiment. In a most general sense, the pallet positioning bar comprises an elongated main body having a face member, at least one lifting flange member oriented substantially perpendicularly to the face member and extending rearward, and a pair of fork members extending from the front of the face bar, the fork members capable of insertion into the fork openings found on standard pallets.
[0015] The pallet positioning bar comprises an elongated main body 11 which extends generally horizontally or parallel to the ground surface when in use. The main body 11 comprises an elongated face member 12 , a lifting flange member 13 and a pair of fork members 21 . The face member 12 presents an abutment surface that is disposed generally vertically relative to the ground surface when first inserted into the pallet. The lifting flange member 13 extends rearward from the face member 12 and presents an abutment surface that is disposed generally perpendicularly to the abutment surface of the face member 12 and generally horizontally or parallel to the ground surface when first inserted into the pallet. The pair of fork members 21 extend forward from the opposite side of the face member 12 and are disposed generally horizontally or parallel to the ground surface during use. The pallet positioning bar is preferably constructed of a hard and durable metal material and is structured and designed to be relatively rigid and sufficiently strong to raise a loaded pallet without excessive deformation.
[0016] The fork members 21 are laterally spaced a sufficient distance apart and are of a length such that a loaded pallet will not excessively tilt to either side when the pallet is raised using the pallet positioning bar. A separation distance of approximately 25-33 inches has been found to be suitable, i.e., a separation distance generally equivalent to the standard separation distance utilized in the industry for forklifts and handtrucks, but the separation distance may also be greater or smaller without departing from the functionality of the device. Preferably the fork members 21 are shorter than the forks found on a typical forklift or handtruck, and a length of approximately 12 to 18 inches has been found to be suitable, but the length may also be greater or smaller without departing from the functionality of the device. As shown in the drawings, the fork members 21 may be formed from angle iron so as to comprise an upper surface member 22 and a runner member 23 , such that they possess a generally L-shaped transverse cross-sectional configuration. Alternatively, the forks could be formed from materials having rectangular, elliptical or circular cross-sections, and may be solid or hollow. The underside of the tips or free ends of the fork members 21 are preferably curved, rounded or slanted, such that initial insertion into the pallet is more readily accomplished and so that the tips will more easily slide along the ground surface when the pallet is being repositioned. In the embodiment shown in the drawings, upper surface member 22 presents a contact surface to abut the underside of the pallet deck and runner members 23 are curved on the ends and provide the ground contacting surface.
[0017] The fork members 21 extend in the forward direction from face member 12 , which is constructed to present a substantially planar abutment surface on its rear side. The face member 12 is composed of a material possessing sufficient strength and rigidity to allow a loaded pallet to be moved when the face member 12 is pushed by the fork tips of a forklift or handtruck.
[0018] At or near the top of the face member 12 , the lifting flange member 13 extends rearward, i.e., to the opposite side relative to the fork members 21 . The lifting flange member 13 is likewise composed of a material possessing sufficient strength and rigidity to allow a loaded pallet to be tilted when the fork tips of a forklift or handtruck abutting the face member 12 are raised. The lifting flange member 13 presents a substantially planar underside or lower contact surface abutted by the upper side of the forks of the forklift or handtruck when the forks are raised. The lifting flange member 13 is disposed relative to the face member 12 such that with the device in position on the ground and fork members 21 inserted into a pallet, the underside of the lifting flange member 13 is a sufficient distance above the ground surface such that the fork tips of the forklift or handtruck may easily be inserted beneath the lifting flange member 13 . In practice it has been found that a distance of approximately 3 inches from the bottom of the face member 12 is suitable. The lifting flange member 13 may be a single elongated member or may comprise a plurality of shorter segments positioned appropriately to contact the forks of the forklift or handtruck. Preferably, lifting flange member 13 extends outwardly a relatively short distance, such as for example approximately 1-2 inches. With this construction, should the operator of the forklift or handtruck raise the forks too high such that the stability of the load may be endangered, the pallet positioning bar and pallet will slip from the fork tips. Thus, the construction provides an automatic safeguard against excessive tilting by the operator.
[0019] In a more preferred embodiment, the main body 11 further comprises a footer flange member 14 extending rearward at or near the bottom of the face member 12 , i.e., in the same direction as the lifting flange member 13 . With this construction, the main body 11 possesses a generally C-shaped transverse cross-sectional configuration, and the main body 11 can be manufactured from channel bar material. Footer flange member 14 provides additional stability for the device when in use. As with the lifting flange member 13 , the footer flange member 14 may be a single elongated member or may comprise a plurality of shorter segments.
[0020] A handle member 15 may also be connected to said main body 11 to make manual insertion, removal and transport of the device easier.
[0021] The pallet positioning bar is utilized in the following manner. After a loaded pallet has been set onto the ground surface and the forklift or handtruck forks have been removed, the fork members 21 of the pallet positioning bar are inserted into the fork openings of the pallet and the main body 11 is pushed against the side of the pallet. The forklift or handtruck operator then advances the fork tips against the face member 12 and beneath the lifting flange member 13 . The operator then raises the forks slightly, thereby lifting the pallet positioning bar and slightly tilting the pallet, such that frictional resistance between the pallet and the ground surface is reduced and movement of the pallet is more easily accomplished. The operator then repositions the pallet by pushing against the face member 12 , either straight on or at an angle if the pallet needs to be turned slightly. With the pallet in the correct location, the forks are lowered, the forklift or handtruck is backed out, and the pallet positioning bar is removed. In certain circumstances where frictional resistance between the pallet and the ground surface is not significant, it may be sufficient to push against the face member 12 without raising the forks to tilt the pallet.
[0022] It is understood that equivalents and substitutions for certain elements described above may be obvious to those of ordinary skill in the art, and the embodiments set forth above in the drawings and description are not meant to be limiting, such that the true scope and definition of the invention is to be as set forth in the following claims. | A method of utilizing a pallet positioning bar to reposition a loaded pallet, the pallet positioning bar having a main body with a face member, a pair of fork members and a lifting flange connected to the face member at or near the top, wherein the fork members are adapted to be manually inserted into the loaded pallet with the main body flush against one side of the pallet, such that the fork tips of a forklift or handtruck can be abutted against the face member beneath the lifting flange, then lifted to raise and tilt the pallet positioning bar and the loaded pallet, enabling the loaded pallet to be repositioned by pushing against the face member. | 8 |
TECHNICAL FIELD
This invention relates to recreational devices and more particularly to a flexible, low profile, toss device.
BACKGROUND ART
A number of circular toss devices have been heretofore provided. The most common toss device presently in use is a flying device sold under the trademark FRISBEE. The flying device is usually above eight inches in diameter and usually made of a hard, rigid plastic material. The side wall is usually curved and has an inside bead. The conventional flying device is usually characterized by hardness and rigidity and therefore may damage people, animals and property during use. The flying device cannot be folded up and put in a pocket, purse or the like when not in use.
DISCLOSURE OF THE INVENTION
In accordance with the present invention there is provided a low profile, soft, circular, dished, body having relatively thin, tear resistant walls and a very short height in relation to diameter. The device can be readily propelled by gripping the side portion on the inside with the index finger and the outside against the top with the thumb in a pencil-type grip. The device is preferably propelled by a wrist action with a forward side arm throwing stroke and will travel relatively long distances with a minimal throwing force required.
BRIEF DESCRIPTION OF THE DRAWINGS
Details of this invention are described in connection with the accompanying drawings which like parts bear similar reference numerals in which:
FIG. 1 is a cross sectional view of a toss device drawn to three quarters scale embodying features of the present invention.
FIG. 2 is a top plan view of the device shown in FIG. 1.
FIG. 3 is a bottom plan view of the device shown in FIG. 1.
FIG. 4 is a side elevation view of the fold-up position for the device shown in FIGS. 1-3.
FIG. 5 is a perspective view of the toss device showing a preferred hand grip for throwing.
DETAILED DESCRIPTION
Referring now to the drawing there is shown a toss device 12 comprised of a soft, flexible, one-piece molded, unitary, low profile, dished body 13. The body 13 has a relatively thin, flat, circumferentially continuous top portion 15 of uniform thickness and a relatively short, relatively thin, annular, circumferentially continuous side portion 16 extending down and at substantially right angles in a direction away from the top portion 15. The side portion has an outwardly projecting circumferentially continuous outside bead portion 17 along the bottom periphery.
The body 13 is preferably made of a rubber like that used in tire treads. Alternatively, the body may be formed of another elastomer exhibiting softness and capable of being molded, such as natural or synthetic rubber, EPDM, BUNA"N", neoprene or a thermal plastic elastomer (TPE) or any suitable equivalent material. A device constructed in accordance with the present invention as shown has a body with a diameter designated A of about 6.7 inches and a height designated B of about 0.73 inches. The top portion 15 has a thickness designated C of about 0.102 inches and the side portion has a thickness designated D of about 0.094 inches. The bead portion 17 has a diameter designated E of about 0.188 inches. The side portion 16 shown is inclined at a selected angle designated F to a line normal or perpendicular to the top portion of about two degrees. The inside corner designated G between the top portion 15 and side portion 16 is rounded having a radius of 0.078 inch. The outside corner designated H between the top portion 15 and side portion 16 is rounded having a radius of about 0.141 inch.
While the above dimensions have been found suitable in a device, the toss device in accordance with the present invention may vary to some extent with that of the embodiment above described. The body may have a diameter in the range of about 5.0 to 10.0 inches. The body may have a height in the range of about 0.25 to 1.50 inches. The top portion may have a thickness in the range of about 0.060 to 0.20 inches. The body may have a side portion with a thickness in the range of about 0.060 to 0.250 inches. The body may have a diameter to height ratio in the range of about 40:1 to 3:1. The bead portion may have a diameter in the range of about 0.088 to about 0.36 inches. The toss device may have an angle to the normal designated F in the range of about 1 to 4 degrees.
The toss device 12 is foldable in half along a diameter line through the center to a fold-up position as shown in FIG. 4 so as to readily fit in a pocket, bag, purse-like container or the like when not in use.
In summary, the features of a toss device made in accordance with the present invention may be described as flexible, durable, safe, not harmful to windows, easy to throw with either the backhand or a side arm, a long range such as 80 yards, the device will stall, it will curve left or right, it will skip off the pavement, it will travel in a straight line, and can be used in frisbee golf. In use the device will return to the thrower when thrown into the wind.
As shown in FIG. 5, in use the device 12 preferably is gripped much like that of a pencil grip with the index finger on the inside of the side portion 16 and the thumb on the top surface of the top portion 15 and the flexible side portion 16 is gripped between the thumb and next finger adjacent the index finger. The device is preferably propelled with a forward wrist action and side arm throwing stroke. The best results have been attained using a sharp forward wrist and arm movement. In flight the top portion 15 dishes or becomes downwardly concave and the side portion 16 flares out at a greater angle than the 2 degrees shown.
By way of example and not limitation the material of the preferred embodiment disclosed would have the following properties:
______________________________________ASTM No. Property Desirable Characteristics______________________________________P 2240 Shore A hardness 80 durometerD 412 Tensile strength 3000 psi Elongation (%) 400%D 624 Tear resistance (Die C) 400 #/inch Weight 0.21 lb.______________________________________
By way of example and not limitation the material of the body would have the following range of properties:
______________________________________ASTM No. Property Desirable Characteristics______________________________________P 2240 Shore A hardness 40-90 durometerD 412 Tensile strength 2000-3500 psi Elongation (%) 250-450%D 624 Tear resistance (Die C) 150-300 #/inch Weight 0.187 lb.-0.437 lb.______________________________________
Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made by way of example and that changes in details of structure may be made without departing from the spirit thereof. | A flexible toss device disclosed has a one-piece dished body with a flat top portion and a relatively short side portion with an outer bead portion. The body is of a soft elastomer material with relatively thin, tear-resistant walls. The top portion and the side portion having sufficient rigidity so that as the side portion flexes outwardly on spinning, during flight, causes the top portion to flex down. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates generally to an electrical connector or penetrator and, more particularly, to a hermetic electrical penetrator for mounting in a containment wall.
Electrical penetrators used in the containment buildings of nuclear penetrators normally utilize a double seal system mounted in a canister weldment. The double seals are generally glass sealed electrical penetrators which are mounted in the end plates of the canister weldment. Due to this conventional arrangement, leak paths are built in the assembly of the components into the canister and in the canister itself. The canister is a relatively expensive structure which is somewhat costly to assemble in a containment wall. Further, the leaking of gas in the canister cannnot be detected.
The purpose of the present invention is to overcome the need for the canister in an electrical penetrator by the use of an economical single electrical penetrator, which may be assembled into a single plate. Further, the present invention provides means for detecting any leaks occurring in the penetrator.
SUMMARY OF THE INVENTION
According to the principal aspect of the present invention, there is provided a hermetic electrical penetrator which may be mounted in a single plate, thus eliminating the need of a double sealed canister weldment assembly. The penetrator comprises a hollow shell in which there are sealed two axially spaced sealing members defining therebetween a leak sensing chamber. One or more electrical contacts extend lengthwise through the sealing members and are sealed therein. A leak sensing port is provided in the wall of the shell providing communication between the leak sensing chamber and the exterior of the shell. The leak port is adapted to be connected to a suitable leak detection device, such as a pressure differential measuring instrument. Thus, any leak path in the penetrator can be detected. Preferably, the sealing members are glass beads and a porous ceramic spacer substantially fills the leak sensing chamber between the glass beads to thereby minimize the volume of the chamber and thereby simplify the measurement of pressure differentials therein. Alternatively, the sealing members may be formed of a non-porous ceramic or a polymer, and the spacer therebetween may be eliminated if the sealing members are mounted close to each other on opposite sides of the leak sensing port in the penetrator shell. Thus, by the present invention, a relatively simple and inexpensive penetrator may be mounted in a single plate and the hermeticity of the sealing members therein may be conveniently determined.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial longitudinal sectional view through one embodiment of the invention wherein an electrical penetrator containing a plurality of contacts is mounted in a single penetrator plate;
FIG. 2 is an elevational view of one end of the penetrator partially broken away; and
FIG. 3 is a partial longitudinal sectional view through an alternative form of an electrical penetrator in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 and 2 of the drawing in detail, there is illustrated a hermetic electrical penetrator, generally designated 10, mounted in an opening 12 extending through a single penetrator plate 14. The plate may be mounted in a containment wall, not shown.
The penetrator 10 comprises a hollow, generally cylindrical shell 16 having a bore 18 extending therethrough. Two axially spaced circular sealing members 20 and 22 are sealed at their outer periphery to an intermediate section 24 of the bore 18 having a slightly reduced diameter. The space between the sealing members defines a leak sensing chamber 26. Preferably, a porous spacer 28 extends between the sealing members and substantially completely fills the sensing chamber 26. Elastomeric interfacial sealing elements 30 and 32 are bonded to the outer surfaces of the sealing members 20 and 22.
A plurality of electrical contacts 34 extend longitudinally through the spacer 28, sealing members 20 and 22, and interfacial sealing elements 30 and 32. Seven of such contacts are illustrated in FIG. 2 by way of example only. Obviously, a larger or smaller number of contacts may be utilized. It is noted that the contact 34 is a double-ended pin contact. The opposite ends of the contact extend beyond the outer faces of the interfacial sealing elements 30 and 32, but do not extend beyond the opposite ends of the shell 16.
The opposite ends of the shell are externally threaded for coupling mating connection members, not shown, to the penetrator.
Polarizing keys 36 are formed on the wall of the bore 18 in the shell adjacent to the opposite ends of the shell for cooperation with keyways formed in the mating electrical connection members. Such other connection members would incorporate socket contacts which are aligned with the double-ended pin contacts 34 in the penetrator 10 so that the mating contacts will engage with each other when such connection members are coupled to the penetrator.
A radially extending leak sensing port 38 is provided in the wall of shell 16 between the sealing members 20 and 22. This port provides flow communication between the leak sensing chamber 26 and the exterior of the shell. The shell embodies a relatively large diameter cylindrical section 40 and a smaller diameter cylindrical section 42. An annular shoulder 44 joins the sections 40 and 42. An outwardly extending annular flange 46 is formed at the left end of the cylindrical section 40 of the shell. The opposite end of the smaller diameter section 42 of the shell is externally threaded, as indicated at 48, to receive a lock nut 50, which secures the penetrator within the opening 12 in the plate 14. Preferably, a washer 52 is interposed between the nut 50 and the plate.
Annular grooves 54 and 56 are formed in the cylindrical sections 40 and 42, respectively, of the shell. O-rings 58 and 60 are mounted in the grooves 54 and 56. The leak sensing port 38 opens at the outer surface of the smaller diameter section 42 between the O-ring 60 and the shoulder 44 on the shell.
The opening 12 in the penetrator plate 14 has a relatively large diameter section 62 and a relatively smaller diameter section 64. The section 62 of the opening is dimensioned to slidably receive the larger diameter section 40 of the shell, while the smaller section 64 of the opening is dimensioned to slidably receive the smaller diameter section 42 of the shell. The O-rings 58 and 60 sealingly engage the sections 62 and 64, respectively, of the opening 12. A generally annular shoulder 66 joins the sections 62 and 64 of the opening 12. This shoulder is axially spaced from the shoulder 44 on the shell 16 when the penetrator is fully mounted in the plate 14 so as to define a generally annular space 68 therebetween. The port 38 communicates with the space 68. A second leak sensing port 70 is formed in the plate 14 and extends from the annular space 68 to the outer surface 72 of the plate. The annular space 68, therefore, provides a manifold which assures flow communication between the ports 38 and 70 regardless of the rotational position of the penetrator 10 within the plate.
The outer end of the leak sensing port 70 in penetrator plate 14 is adapted to be connected to a suitable leak detection device, for example, a pressure differential measuring instrument, not shown. The port 70 is in flow communication with the leak sensing chamber 26 in the electrical penetrator 10 via the annular space 68 and the port 38 so that any leaks between the sealing members 20, 22, and the wall of the bore 18 in the shell, and between the sealing members and the contacts 34, can be detected by the instrument connected to the outlet of the port. Further, any leaks which might exist between the external surface of the penetrator shell and the wall of the opening 12 in the plate caused by failure of the O-ring seals 58 and 60 may also be detected. Thus, by the present invention, any leaks in the electrical penetrator 10 per se, or its mounting in the plate 14, can be detected.
Preferably, the sealing members 20 and 22 in the penetrator shell are glass beads or discs, which have a compression seal with the wall of the bore 18 of the shell and with the contacts 34. In the forming of the glass seals, it is necessary to provide the spacer 28 to support the beads. During assembly of the penetrator, the contacts are inserted into the spacer 28 and one of the glass beads, for example, bead 22. The assembly thus formed is inserted into one end of the shell, for example, the right end in FIG. 1. Each glass bead is formed with an outwardly extending annular flange, not shown, adjacent to the outwardly facing planar surface of the bead. The flange on bead 22 abuts against an annular shoulder 74 on the wall of the bore 18. Thereafter, the second glass bead 20 is inserted into the left end of the penetrator shell until its flange engages a second shoulder 76 on the interior of the shell. The shell is then disposed vertically with carbon fixtures, not shown, bearing against the top and bottom glass beads. The assembly is then placed in a furnace to fuse the beads to the shell and to the contacts 34. During the heating operation, the outer flanges on the beads disappear, thus producing a penetrator assembly as shown in FIG. 1. Thereafter, the assembly is removed from the furnace, the carbon fixtures are withdrawn from the opposite ends of the shell, and the interfacial seals 32 are inserted into the ends of the shell with an adhesive on their inner faces, which bond the elastomer seals to the glass beads.
The spacer 28 may be formed of a porous ceramic in which the interstices within the spacer provide a flow passage between the contacts 34 and the exterior of the spacer so that any leaks occurring between the contacts and glass beads can be detected at the port 38.
During the heating operation which is performed to effect the sealing of the glass beads 20, 22 to the shell and contacts, some of the glass flows into the adjacent surfaces of the ceramic spacer, thereby bonding the two parts together. Sometimes, the molten glass will also flow around a substantial portion of the contacts to impair the flow passage from the contacts to the sensing port 38 which is necessary to detect any leak occurring between the contacts and the glass beads. Further, some ceramics are only partially porous and, therefore, do not provide an open flow path between the contacts and the exterior of the spacer. Consequently, according to another feature of the invention, the ceramic spacer 28 is divided into two parts, designated 28a and 28b, which are axially displaced from each other within the shell 16. The opposing faces 78 and 80, respectively, on the parts 28a and 28b provide a radially extending planar flow path between the leak sensing port 38 and each contact, whereby leaks at the contacts may be detected. Thus, by this arrangement, the two parts 28a and 28b of the spacer may be formed of a non-porous material, since a leak path is provided between the opposed faces of the parts. The provision of the spacer between the sealing members 20 and 22 has the further advantage of reducing the volume of the leak sensing chamber 26, thereby making pressure differential measurements easier to detect.
In an alternative embodiment of the invention, the sealing members 20, 22 may be formed of non-porous ceramic, which is bonded to the shell 16 and to the contacts 34 by brazing or other suitable techniques. By utilizing ceramic sealing members, the pressure heating operation is not required as when using glass beads to form glass-to-metals seals. Hence, the spacer 28 could be eliminated, in which case, however, it would be preferred that the ceramic sealing members be mounted in very close relationship with respect to each other adjacent to opposite sides of the leak sensing port 38 so as to minimize the volume of the leak sensing chamber therebetween. Alternatively, a suitable spacer could be provided between the ceramic seals as in the embodiment illustrated in FIG. 1.
Reference is now made to FIG. 3 of the drawing, which shows still a further embodiment of an electrical penetrator in accordance with the present invention. In this embodiment, the basic structure is as previously described and like numbers primed are used to indicate like or corresponding parts. Rather than utilizing glass or ceramic sealing members, in the embodiment illustrated in FIG. 3 the penetrator 10' incorporates polymeric sealing members 20' and 22' to provide a seal between a single, large power contact 34' and the shell 16'. Annular corrugated metal flanges 84 and 86 are welded at their outer peripheries to the shoulders 76' and 74', respectively, on the interior of the shell. The inner regions of the flanges are embedded in the seals 20', 22'. The seals are bonded to the flanges and the contact 34'. As in the previous embodiments, the leak sensing port 38' is positioned between the seals 20' and 22' so as to be in flow communication with the leak sensing chamber 26' between the seals. In order to reduce the volume of the chamber 26', a porous plastic spacer 28' is mounted in the chamber between the polymeric seals 20', 22'. A porous ceramic spacer could be utilized in place of a porous plastic spacer. As previously noted, the spacer could be eliminated if the sealing members 20' and 22' are positioned sufficiently close to minimize the volume of the leak sensing chamber 26' so that pressure differential measurements could be easily made with relatively inexpensive instrumentation.
While the contacts in FIGS. 1 and 3 have been illustrated as being double-ended pin contacts, it will be appreciated that other forms of contacts could be utilized. For example, the ends of the contacts could be formed as solder pots for directly soldering to wires. Alternatively, one or both ends of the contacts could be in the form of a socket contact, for engagement with a mating pin contact in a second connection device. It will be further noted that while the drawing illustrates only a single electrical penetrator 10 mounted in the plate 14, a plurality of such penetrators could be mounted in the plate with each leak sensing port 38 associated therewith connected to a common instrument outlet port 70, so that a single instrument may be utilized to detect leaks in a plurality of electrical penetrators.
In view of the foregoing, it is seen that by the present invention there is provided a relatively simple and inexpensive hermetic electrical penetrator embodying a leak monitored double seal assembly which enables leaks to be detected in the penetrator. The penetrator can be assembled into a single plate, thus eleminating the necessity of a double sealed canister weldment assembly as is normally utilized in nuclear penetrators. It will further be appreciated that while the present invention has been described specifically in connection with an electrical penetrator for a nuclear containment wall, the penetrator could also be utilized in submarine hulls, underwater chambers, and pressure vessels with the same advantages achieved thereby. | A hermetic electrical penetrator comprising a shell mounted in a single penetrator plate. A pair of axially spaced sealing members are sealed inside the shell defining a leak sensing chamber therebetween. One or more electrical contacts extend longitudinally through the sealing members in the shell. A sensing port in the wall of the shell communicates with the sensing chamber so that any leakage of gas through the shell can be detected by measuring the pressure differential between the inside and the outside of the shell. Preferably the sealing members are glass beads, and a porous ceramic spacer extends between the beads substantially filling the leak sensing chamber so that pressure differentials may be more easily detected. | 8 |
BACKGROUND
1. Field of Invention
This invention relates to a golf ball teeing device that easily permits a golfer, without bending over, to insert a golf tee into the ground with a golf ball situated on top of the tee in preparation for driving the ball.
2. Description of Prior Art
Elderly golfers often find it difficult to bend over to place a golf tee in the ground and place a ball upon the tee. Additionally, golfers with back or knee problems have the same difficulty.
Inventors have described several devices that allow the tee and ball to be positioned without bending over. Some of these devices can also be used to retrieve the tee out of the ground once the ball has been hit. These devices all involve a mechanism that clamps the ball and tee to the device which is mounted to the end of a handle or pole long enough to preclude the user from having to bend over. At the held end of the pole is a control which is in communication with the clamping mechanism. This control permits the golfer to unclamp the tee and ball from the device once the tee has been inserted into the ground.
All of these devices are relatively elaborate and incorporate the use of several moving parts as exemplified by U.S. pat. Nos. 2,609,198 to Armstrong (1952), 4,526,369 to Phelps (1985), 4,616,826 to Trefts (1986), 4,714,250 to Henthorn (1987), 4,969,646 to Tobias (1988), 4,819,938 to Hill (1989), 4,949,961 to Milano (1990), 4,951,947 to Kopfle (1990), 5,080,357 to Wolf(1992), 5,171,010 to fanoue (1992), 5,205,598 to Miller (1993), 5,330,177 to Rogge (1994), 5,330,178 to Geishert (1994), 5,439,213 to Pimentel (1995), 5,499,813 to Black (1996), and 5,503,394 to Mauck and Shelton (1996).
No inventor known to me has been able to eliminate the need for the golfer to manually unclamp the ball and tee from the device. Therefore, the prior devices all require a long handle with an unclamping control mounted to the end of the handle. Furthermore, they require some sort of mechanical linkage between the control and the clamping mechanism at the other end. This causes the following significant disadvantages common to all prior ball teeing devices:
(a) The long handle and elaborate mechanisms incorporated in these devices weigh too much to be comfortably carried by a golfer as an accessory to golf clubs.
(b) The elaborate nature of these devices make them too large to be carried in a golf bag in addition to golf clubs.
(c) The number of parts required causes the material and labor costs associated with producing these devices to be inefficient with regard to bringing these devices to the buying public.
(d) The large. elaborate nature of these devices causes them to be visually unappealing as a golf accessory prohibiting their commercial success in the marketplace.
In addition to the above disadvantages, the use of such devices is cumbersome, time consuming, and inefficient. Using these devices to tee up a ball and to retrieve the tee without bending over requires four trips to the golf bag as the golfer alternates between the device and his club. Some inventors have attempted to minimize this by incorporating the use of a sharp member to anchor the device to the ground in an upright position while the golfer uses the club. This allows the device and club to be transported to and from the golf bag together instead of alternately as described in U.S. pat. Nos. 4,951,947 to Kopfle (1990), 5,439,213 to Pimentel (1995), 5,499,813 to Black (1996), and 5,503,394 to Mauck and Shelton (1996). However, this requires the golfer to operate the large heavy device one-handed while holding the golf club in the other hand to keep from bending over. Additionally, the sharp anchor can be a safety hazard to the golfer.
With regard to other golf related inventions, inventors have described small light weight devices which can be temporarily attached to the end of a golf club to accomplish different tasks. For example U.S. pat. Nos. 2,801,875 to McEvoy (1957), 2,819,109 to Borah (1958), and 2,833,584 to McEvoy (1958) describe devices which are attached to the grip end of a golf club for use as golf ball retrievers.
Similarly, U.S. pat. Nos. 3.870,300 to Amendola (1975), 5,012,872 to Cohn (1991), and 5,094,456 to Mitchell (1992) describe devices which are attached to the grip end of a golf club to serve as sand trap rakes. These devices utilize a golf club as the handle making the devices themselves small, lightweight, and portable.
However, no other inventor has devised a tee and ball placing device which eliminates the need for an unclamping control incorporated into a long pole thereby allowing a golf club to be used as the handle. The teeing devices listed above all require the user to manually release the tee and ball by actuating some sort of control linkage incorporated into a long pole.
OBJECTS AND ADVANTAGES
Accordingly. several objects and advantages of my invention are:
(a) to provide a golf ball teeing device which can operate without a manually controlled unclamping mechanism integral with the device;
(b) to provide a golf ball teeing device which can utilize a golf club as a handle;
(c) to provide a golf ball teeing device which contains relatively few parts making the device lightweight;
(d) to provide a golf ball teeing device which is small, portable, and does not require a substantial amount of space in a golf bag;
(e) to provide a golf ball teeing device which can be quickly and easily used without requiring the cumbersome juggling of a large device and a golf club;
(f) to provide a golf ball teeing device which can also be used to retrieve the golf tee once the ball has been hit for both instances of the tee laying horizontally on the ground or remaining vertically inserted into the ground.
Further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric illustration of the front of a specific illustrative embodiment. FIG. 2 is an isometric illustration of the rear of a specific illustrative embodiment. FIG. 3 is an isometric illustration of a specific illustrative embodiment from another angle. FIG. 4 is a partial sectional view taken along line 4--4 of FIG. 1 showing a golf club grip inserted into the preferred embodiment. FIG. 5A is a front view showing a specific illustrative embodiment prior to inserting the tee into the ground with the ball and tee being clamped together. FIG. 5B is a front view showing a specific illustrative embodiment as the tee is inserted into the ground. FIG. 5C is a front view showing a specific illustrative embodiment ready to release the tee and ball which are no longer clamped to the device.
______________________________________Reference Numerals In Drawings______________________________________10 teeing device 12 golf ball14 golf tee 16 head of golf tee18 shank of golf tee 20 golf club grip22 housing 24 upper housing26 lower housing 28 top wall30 rear wall 32 left vertical wall34 right vertical wall 36 left recess38 right recess 40 opening42 bottom wall 44 slot46 rounded end 48 delayed urging means50 interface member 52 annular wall54 taper 56 gripping fingers58 voids 60 rounded bottoms62 outward flares 64 chamfered edges66 supporting ribs 68 clip70 radius 72 inward bend74 outward bend______________________________________
DESCRIPTION OF THE PREFERRED EMBODIMENT
THE entire device is referred to generally by the reference numeral 10. A golf ball is referred to generally by the reference numeral 12. A golf tee is referred to generally by the reference numeral 14, having a head 16, and a shank 18. A golf club grip is referred to generally by the reference numeral 20.
The perferred embodiment of the present invention is illustrated in FIG. 1. The invention comprises a housing 22, which includes an upper portion 24, and a lower portion 26. The upper portion 24 includes a top wall 28, a rear wall 30, left vertical side wall 32, and a right vertical side wall 34. Side walls 32 and 34 incorporate a recessed portion 36 and 38 respectively to facilitate easy removal of the device 10 from the teed golf ball 12. The lower end of the rear wall 30 contains an opening 40 that extends between the two side walls 32 and 34. The opening 40 has a height that will permit passage of the golf tee shank 18 but will not allow passage of the golf tee head 16 and is used to facilitate the retrieval of the golf tee 14 lying horizontally on the ground. The lower portion 26 of the housing 22 includes a bottom wall 42 which contains a slot 44 that extends inward from the edge of the bottom wall 42. The slot 44 terminates with a rounded end 46. The entire wall of the slot 44 is angled such that the slot is larger on the top surface of the bottom wall 42 than the bottom surface of the bottom wall 42. The edges of the housing 22 are typically chamfered or rounded to avoid snagging or personal injury.
Attached to the lower surface of the top wall 28 is a delayed urging means 48 which exhibits a delayed rebound after being compressed. Examples of such delayed urging means 48 are the ISODAMP® C-3000 series of energy absorbing foams manufactured by E-A-R Division, Cabot Corporation, Indianapolis, Ind. These foams rebound very slowly after being compressed. In the preferred embodiment, a cylindrical piece of E-A-R C-3002-50 low-recovery foam is used. However, means other than low-recovery foam could be used to provide a delayed urging function. The delayed urging means 48 is typically fastened to the top wall 28 by means of an adhesive. The placement of the delayed urging means 48 on the underside of the top wall 28 is such that it will be directly over the golf ball 12 when placed in the housing 22.
Attached to the bottom of the delayed urging means 48 is a rigid ball interface member 50 used to provide a uniform surface to contact the golf ball 12. In the preferred embodiment, this member is a ring shaped object with an outer diameter equal to the delayed urging means 48 diameter and an inner diameter sufficiently large enough to provide engagement of the golf ball 12. However interface members of other shapes would equally suffice. The interface member 50 is typically attached to the delayed urging means 48 by means of an adhesive. FIG. 3 shows a better view of the interface member 50.
The housing 22 height, interface member 50 size, slot 44 dimensions, and delayed urging means 48 size all affect the performance of the device 10. This combination of dimensions must be such that when the golf ball 12 is placed in the housing 22 below the interface member 50 and the golf tee 14 is slid into the slot underneath the ball 12, the delayed urging means 48 is slightly compressed exerting enough of a downward force to securely hold the ball 12 and tee 14 into the device 10. Additionally, these dimensions must be such that the delayed urging means 48 sufficiently further compresses due to the upward force on the tee 14 when the device 10 is used to insert the tee 14 into the ground. In the preferred embodiment, the interior height of housing 22 is 2.24 inches, slot 44 is 0.36 inches wide with angled walls at 21°, the interface member height is 0.12 inches with an inner diameter of 0.64 inches, and the delayed urging means 48 has a diameter of 0.75 inches and a height of 0.50 inches in its uncompressed state. These dimensions describe one possible embodiment of the invention. Other combinations of dimension values could also be used to achieve successful operation of the device 10.
Extending from the upper side of the top wall 28 is the portion used to attach the device 10 to a golf club grip 20 as shown in FIG. 4. From the top wall 28, an annular wall 52 extends upward vertically and then flares outward becoming a taper 54. The annular wall 52 provides clearance for the end of the golf club grip 20 which is often convex in shape. The taper 54 ensures that the device 10 is aligned with the axis of the golf club by centering the end of the golf club grip 20. The diameters at the bottom and top of the taper 54 are sized to accommodate the full range of golf club grip 20 diameters available in the market place. Above the taper 54 the wall angles inward forming a plurality of individual gripping fingers 56 capable of flexing outward. In the preferred embodiment four gripping fingers 56 are used; however, any number greater or equal to two would work. FIG. 1 shows how the gripping fingers 56 are separated from each other by voids 58. The voids 58 incorporate rounded bottoms 60 to reduce stress concentrations in the flexing material. The gripping fingers 56 are of sufficient height to prevent the device 10 from becoming skewed with respect to the axis of the golf club. FIG. 4 shows how the gripping fingers 56 incorporate outward flares 62 at the top to provide easy insertion of the golf club grip 20. The very top of the gripping fingers 56 incorporate chamfered edges 64 to also aid in the insertion of the golf club grip 20.
FIG. 1 shows a series of supporting ribs 66 used to provide strength to the annular wall 52 and to the taper 54 below the gripping fingers 56. These ribs 66 ensure that the stress created in the material during insertion of a golf club grip 20 will not cause a fracture in the material.
FIG. 2 shows a clip 68 extending from the rear of the housing 22 just above the opening 40. The clip 68 is shaped with a large enough radius 70 to permit the device 10 to be clipped to the side of a typical golf bag. The clip 68 incorporates an inward bend 72 towards the housing 22 permitting the device 10 to be securely clipped to the pocket of a golfer's clothing. An outward bend 74 at the top of the clip 68 allows the device 10 to be easily clipped to a golf bag, pocket, or belt.
In the preferred embodiment the entire device 10, except delayed urging means 48, is molded from an economical, flexible plastic material such as ABS. However, the device 10 can consist of any other material that exhibits the elasticity and impact resistance characteristics suitable for the application.
From the description above, a number of advantages of the present invention become evident:
(a) The device automatically unclamps the ball and tee once the tee is pushed into the ground since the delayed urging means becomes further compressed and will not immediately rebound.
(b) The golfer can use a golf club as the device handle since no handle mounted unclamping control is needed.
(c) The device makes it possible to tee up a golf ball from a standing position without the cumbersome use of relatively very large prior mechanisms.
(d) The device allows a golfer to tee up golf balls without bending over by only carrying a small, lightweight device during a golf outing.
(e) The device can be used to retrieve golf tees from the ground even if they are in a horizontal orientation.
Operation-FIGS. 5A, 5B, 5C
In use, the golfer removes the desired golf club from the golf bag and then unclips the device 10 from the golf bag, a pocket, a belt, or wherever the device 10 is stored. The device 10 is then attached to the golf club by pushing the gripping fingers 56 fully onto the end of the golf club grip 20 until the end of grip 20 comes in contact with the taper 54. A golf ball 12 is then placed in the housing 22 below the ball interface member 50. A golf tee 14 is then slid into slot 44 causing the ball 12 to push against the interface member 50 somewhat compressing the delayed urging means 48. The delayed urging means 48 exerts a downward force on the ball 12 clamping the ball 12 and tee 14 securely to the device 10 as shown in FIG. 5A The golf club is then held by the golfer at the club head end with the grip end towards the ground. The golf club is positioned in a vertical orientation with the shaft of the golf club perpendicular to the ground. The golfer holds the golf club at a height such that the tip of the golf tee 14 is a short distance above the ground as also shown in FIG. 5A. The golfer then moves the golf club straight down sinking the golf tee 14 into the ground. As the tee 14 enters the ground it exerts an upward force on the ball 12 causing the delayed urging means 48 to substantially compress. As this happens, the device 10 lowers with respect to the ball 12 and tee 14 such that the slot 44 is no longer in full contact with the underside of the tee head 16 as shown in FIG. 5B. Once the golf tee 14 has been sunk to the desired depth into the ground, the golfer releases the ball 12 and tee 14 from the device 10 by slightly moving the golf club straight up until the interface member 50 no longer is in contact with the ball as shown in FIG. 5C. The delayed urging means 48 remains compressed for a period of several seconds allowing the device 10 to be laterally removed from the teed ball 12 by moving the golf club in a motion parallel to the ground.
After teeing up the ball 12, the golfer then pulls the device 10 off the end of the golf club and uses clip 68 to temporarily fasten the device 10 to a pocket or belt while the ball 12 is hit. The device 10 can then be reinstalled on the golf club grip 20 to be used to retrieve the golf tee 14 without bending over. For instances when the tee 14 remains in the ground while hitting the ball 12, the golfer uses the golf club as a long handle and maneuvers slot 44 of the device 10 under the head 16 of the tee 14. The tee 14 can then be pulled out of the ground and retrieved without bending. For instances when the tee 14 comes out of the ground while hitting the ball 12 and is lying horizontally on the ground, the golfer again uses the golf club as a long handle and retrieves the tee 14 using the device 10. This is accomplished by maneuvering the bottom wall 42 of housing 22 underneath the shank 18 of the tee such that the tip of the tee 14 protrudes through opening 40 of the housing 22. The opening 40 will not permit passage of the tee head 16 allowing the tee 14 to be scooped up without bending.
Accordingly, this invention allows a golfer to easily tee up a golf ball without bending over. In addition, the invention permits a golfer to easily retrieve a golf tee without bending over whether or not the tee came out of the ground while hitting the ball. Furthermore, the teeing device has the additional advantages in that
it permits a golf club to be utilized as the handle reducing the weight and size of the device;
it is very simple to use with no cumbersome controls to release the tee and ball;
it can easily and nonintrusively be clipped onto a golfer's apparel while hitting the ball;
it can easily be attached to a golf bag;
it can be made from far fewer parts than prior tee setting devices.
Although the description above contains many specifics, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. For example, a means other than low-recovery foam could be used to provide a delayed urging means. Furthermore, the dimensions given of the housing, interface member, low-recovery material, and slot could be different, the ball interface member could be eliminated; the gripping fingers could be of a different shape, the clip could be shaped differently, the supporting ribs could be eliminated, etc.
Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. | A small, lightweight golf ball teeing device is disclosed for allowing a golfer to tee up a golf ball without bending over using a golf club as a handle for the device. A housing positions the golf ball over the golf tee. A delayed urging means is used to clamp the ball and tee to the housing. While the tee is inserted into the ground, the delayed urging means compresses and rebounds slowly releasing the ball and tee from the device. Gripping fingers are positioned on top of the housing to provide a secure, aligned attachment to a golf club grip. An opening in the housing permits horizontal golf tees to be scooped up without bending. A clip is incorporated with the housing to provide attachment to golf bags, belts, etc. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND
U.S. Pat. No. 8,074,742 issued to Scott et al. discloses a reaming tool for use during emplacement of tubular strings such as casing or liner in wellbores drilled through subsurface formations.
A rotary power section described in the above referenced patent may include a turbine section operated by flow of drilling or other fluid through an interior of the wellbore tubular being emplaced so that a reaming head can rotate without rotation of the wellbore tubular. It has been observed that fluid pressure used to operate the rotary power section may place large axial loading on bearings included in the power section to support such loading. It is desirable to have a reaming tool power section for use in emplacement of wellbore tubular that has more balanced axial loading resulting from fluid pressure.
SUMMARY
An apparatus for cutting a wellbore according to one aspect includes the apparatus a motor having a stator and a rotor. The rotor has an output shaft connected to a cutting structure so as to drive the cutting structure. The stator and rotor are spaced radially outwardly of the axis of rotation of the rotor such that at least one of the stator and the rotor is formed with an access bore that extends through the motor to a position adjacent the cutting structure. A further object can pass therethrough, without obstruction from the stator and rotor. The further object comprises a further cutting structure of the apparatus. A flow diverter is disposed in the motor proximate a connection between the motor and the wellbore tubular, the flow diverter having a first fluid outlet in fluid communication with a power section of the motor, the flow diverter having a second fluid outlet in fluid communication with the access bore. The flow diverter is coupled to the stator such that axial loading created by fluid pressure is substantially transferred to the stator.
Other aspects and advantages will be apparent from the description and claims which follow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional side view of an example reaming tool including an annular rotary power section
FIG. 2 is another sectional side view of the reaming tool of FIG. 1 .
FIG. 3 is a more detailed part sectional, part cut away side view of the reaming tool of FIG. 1 showing a further cutting structure in two consecutive positions, with part of the apparatus in phantom;
FIG. 4 is a more detailed part sectional, part cut away side view of the reaming tool of FIG. 2 showing a further cutting structure in three consecutive positions.
FIG. 5 shows a flow diverter inside the reaming tool to provide fluid flow to both the rotary power section (turbine) and to an interior of the reaming tool and reaming head.
DETAILED DESCRIPTION
Most of the details of operating a fluid powered reaming tool for use with inserting a casing or liner into a wellbore drilled through subsurface formations are set forth in U.S. Pat. No. 8,074,742 issued to Scott et al. and incorporated herein by reference. Relevant portions of the foregoing patent will be set forth below to explain operation of a pressure balanced rotary power unit for a reaming tool used with inserting casing or liner into a wellbore.
FIG. 1 shows a lower part of a wellbore 1 formed by a prior drilling operation. The wellbore 1 is being lined or already has been lined with a “string” of wellbore tubulars in the form of a casing 3 (or a liner) having a lowermost end 4 . An annular space 6 is defined between the outer surface of the casing 3 and the wall of the wellbore 1 . The annular space 6 may be filled with cement once drilling and reaming operations are complete.
A reaming tool 5 comprises a cutting structure which, in this example, may be a reamer shoe 7 connected to an output shaft 9 . Rotation of the output shaft 9 rotates the reamer shoe 7 . In this example the reamer show 7 can be sacrificed by drilling or reaming after the casing 3 (or liner) is moved to its intended depth in the wellbore 1 .
The output shaft 9 comprises a rotor of a motor generally indicated at 11 . The rotor 11 in this example may be radially inward of a radially outward stator 13 fixedly connected to the lowermost end 4 of the casing 3 .
The stator 13 may be concentric with and extends around the periphery of the output shaft 9 and may thus be of hollow tubular form when viewed from the side or in transverse cross section. The stator 13 is therefore radially spaced from the rotational axis 10 of the output shaft 9 such that it does not, when viewed in cross section from the side, extend across the output shaft 9 . The output shaft 9 may be formed with an access bore 15 that extends along the length of the motor 11 from the reamer shoe 7 to the opposite, distal longitudinal end of the output shaft 9 , that is, the longitudinal end adjacent the lowermost end 4 of the casing 3 . The access bore 15 in this example may be co-axial with the axis of rotation 10 of the output shaft 9 . The access bore 15 may also extend in a direction aligned with but not co-axial with, the axis of rotation 10 .
The access bore 15 may have an internal diameter selected to receive and enable free passage therethrough of a further object and may arranged such that the further object can be located directly adjacent the reamer shoe 7 . The further object could comprise any desired device which may include, for example, a sensing device to transmit a signal indicative of physical parameters relevant to the cutting process. In the example, the further object may comprise a further cutting structure comprising a drill bit 17 connected to a drill pipe, pipe string or coiled tubing, shown generally at 19 .
In using the apparatus 5 , the casing 3 is moved through the wellbore 1 , which has already been drilled to a selected depth in the subsurface. The motor 11 may be activated to drive the output shaft 9 to rotate the reamer shoe 7 by pumping fluid through an interior of the casing 3 or liner. Rotating the reamer shoe 7 aids movement (“running”) of the casing 3 into the wellbore 1 to the selected depth.
Once the casing 3 has reached the selected depth, the motor 11 may be deactivated. The drill bit 17 and drill string 19 may then run be into the casing 3 . When the drill bit 17 reaches the lowermost end 4 of the casing 3 , the drill bit 17 may be moved into the access bore 15 of the output shaft 9 so as to effectively pass through the interior of the motor 11 , i.e., the functional parts of the motor are radially outward of the output shaft 9 and drill bit 17 and do not obstruct passage of the drill bit 17 toward the reamer shoe 7 . The motor workings do not therefore require drilling out or removal to allow the drill bit 17 access to the reamer shoe 7 .
When the drill bit 17 reaches the reamer shoe 7 , rotation of the drill bit 17 allows the drill bit 17 to cut through the sacrificial reamer shoe 7 so as to project beyond the reamer shoe 7 so as to move into contact with material to be drilled through to form a subsequent section of wellbore.
Referring to FIG. 2 another example reaming tool 21 is shown with like features being given like references to the reaming tool 5 described above. In the present example a modified output shaft 22 is concentric with and is radially outward of the motor stator. In the present example the motor stator may comprise a radially inward tubular stator 23 fixed to the lowermost end 4 of the casing 3 or liner. The tubular stator 23 may be formed with an access bore 25 that extends from the reamer shoe 7 to the lowermost end 4 of the casing 3 , in the present example co-axially with the axis of rotation 10 of the modified output shaft 22 . A further object, which in this example again comprises the drill bit 17 and drill pipe 19 , may be run into the access bore 25 in the tubular stator 23 .
Referring to FIG. 3 a flared portion 14 of the radially outward stator 13 may be rotationally locked to an interior surface of the lowermost end 4 of the casing 3 . Such locking can be achieved using any suitable locking means.
The radially inward output shaft rotor 9 may be rotatably mounted on the stator 13 using a suitable combination of rotational bearings 27 . Additionally a plurality of axial thrust bearings 29 may provided to limit axial movement between the rotor 9 and the stator 13 while still allowing relative rotation of these components. The thrust bearings 29 can be arranged to allow limited axial movement if desirable.
Any desired type, number and position of bearings may be used as required to deal with the loads generated. The motor rotor 9 and stator 13 can comprise any desired structure and components to generate power to rotationally drive the rotor 9 . In this example, the rotor 9 and stator 13 together comprise a turbine arrangement wherein the rotor 9 comprises turbine blades 30 arranged to deflect fluid pumped between the rotor 9 and stator 13 so as to convert some of the energy of the fluid into rotation of the rotor 9 and hence the reamer shoe 7 .
The stator 13 comprises a fluid inlet 31 between the stator 13 and the internal rotor 9 , at the lowermost end 4 of the casing 3 , the fluid inlet 31 being radially outwardly spaced from the axis 10 .
A flow diverter 32 (shown in phantom) is provided adjacent the fluid inlet 31 and serves to divert fluid pumped down the casing 3 radially outwardly so as to flow into the fluid inlet 31 .
The fluid flow path is indicated by arrows ‘A’. Having been diverted by the flow diverter, the fluid enters the inlet 31 adjacent the lowermost casing end 4 . The fluid is pumped in a direction generally parallel to the axis of rotation 10 of the rotor 9 in the void defined between the concentric rotor 9 and stator 13 , and subsequently exits the void and the turbine arrangement radially inwardly through the outlet 33 into the access bore 15 . The fluid then travels along the access bore 15 and subsequently generally radially outwardly and/or downwardly through jetting apertures (not shown) formed in the reamer shoe 7 . The fluid thus functions as a lubricant for the reamer shoe 7 before being forced up the annular space 6 between the casing 3 and the wellbore 1 .
Referring additionally to FIG. 4 , a flared portion 37 of the radially inward stator 23 of the second described reaming tool (in FIG. 2 ) 21 may be locked to the interior surface of the lowermost end 4 of the casing 3 . This can again be achieved using any suitable locking means.
The bearings, turbine arrangement and fluid flow path are otherwise similar to those described above with reference to FIG. 3 . In each example, the bearings could be lubricated by the fluid used to drive the turbine arrangement. In each example, the rotor of the motor could be integral with the output shaft or that these could comprise separate components connected together. Likewise it is possible that the output shaft may be integral with the cutting structure or that these could comprise separate components connected together, e.g., by threaded couplings of types known in the art.
As explained in the Background section herein, the axial thrust bearings (e.g., 29 in FIG. 3 ) are subject to loading resulting from pressure drop in the motor. Referring to FIG. 5 , a portion of an example motor in a reaming tool is shown having balanced fluid pressure that may relieve some of the pressure-induced axial loading. The reaming tool motor section shown in FIG. 5 may be configured with an external stator 13 and internal output shaft (rotor) 9 as in FIG. 1 . It should be understood that the motor arrangement of FIG. 2 may be used to the same effect. In FIG. 5 , the flow diverter 32 may be configured to have a first fluid outlet 35 that directs part of the fluid flow from within the casing 3 or liner into the motor 11 . A second fluid outlet 34 directs another part of the fluid flow from within the casing into the interior of the output shaft 9 (i.e., the access bore), and thence to the reamer shoe ( 7 in FIG. 1 ). If a motor such as shown in FIGS. 2 and 4 is used, the second fluid outlet will direct the other part of the fluid flow into the interior of the stator ( 23 in FIG. 4 ), i.e., the access bore, and thence to the reamer shoe 7 through a suitable bearing and flow crossover arrangement (not shown).
In the drilling or reaming of a wellbore with a motor which uses fluid flow as a power source there is a pressure drop through the motor. This pressure drop acts against the top most end of the rotary power output shaft in the manner of acting against a piston.
The cross sectional area of the equivalent piston is generally considered to be a function of the inside diameter of the body of the tool. This cross sectional area multiplied by the pressure drop through the motor is translated into an axial load through the motor which acts against any bearing system in the motor for carrying axial load. The pressure drop caused axial loading may be substantial.
The motor section shown in FIG. 5 seeks to reduce the hydraulically caused axial loading by manipulation of the effective piston area under hydraulic pressure. As the fluid passes through the motor 11 assembled to the output shaft 9 and reaches the axial end of the motor 11 there will be an associated pressure drop. The lowered pressure is also present at the cross section of the upper part of the output shaft 9 . By way of explanation, there are essentially two piston areas. There is a primary piston area created by parts ‘B’ & ‘A’, this piston area is connected by threads T to the body 13 . The primary piston area carries the majority of hydraulically induced pressure loading by carrying this load through into the body 13 and not into the axial bearings. A secondary or minor piston area is created by the cross section of the rotor blade area. There are circumferentially positioned axial bypass ports in part A, which allows the drilling fluid to enter into the motor 11 . The motor 11 has a smaller effective piston area than parts B & A combined. In this way axial load reduction may be reduced up 80% of that of an uncompensated system.
It can be understood that as the annular motor has a relatively small cross section as contrasted with the output shaft there will be a resultant reduction in hydraulic load imparted to the axial thrust bearings while still maintaining a desired relatively high pressure without detriment to produced power and hole cleaning efficiency when the drilling fluid is ported to the wellbore annulus ( 6 in FIG. 1 ). This reduction in axial loading which is imparted to the axial bearing of the power output shaft facilitates a reduction in the number of bearing sets required to carry the axial loading efficiently.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | An apparatus for cutting a wellbore includes a motor having a stator and a rotor. The rotor has an output shaft connected to a cutting structure. The stator and rotor are spaced radially outwardly of the axis of rotation of the rotor such that at least one of the stator and the rotor had an access bore extending through the motor to adjacent the cutting structure. A further object can pass therethrough, without obstruction. The further object comprises a further cutting. A flow diverter is disposed in the motor proximate a connection between the motor and a wellbore tubular, and has a first fluid outlet in fluid communication with a power section of the motor, and a second fluid outlet in fluid communication with the access bore. The flow diverter is coupled to the stator such that axial loading created by fluid pressure is substantially transferred to the stator. | 4 |
BACKGROUND OF THE INVENTION
The present invention is concerned with side chain aldehydes of 17β-N-alkyl carbamoyl-4-aza-5α-androst-1-en-3-one compounds as testosterone-5α-reductase inhibitors for the treatment of benign prostatic hypertrophy.
The art reveals that certain undesirable physiological manifestations, such as ache vulgaris, seborrhea, female hirsutism, male pattern baldness and benign prostatic hypertrophy, are the result of hyperandrogenic stimulation caused by an excessive accumulation of testosterone or similar androgenic hormones in the metabolic system.
It is now known in the art that the principal mediator of androgenic activity in some target organs is 5α-dihydrotestosterone, and that it is formed locally in the target organ by the action of testosterone-5α-reductase. It is also known that inhibitors of testosterone-5α-reductase will serve to prevent or lessen symptoms of hyperandrogenic stimulation.
For example, U.S. Pat. Nos 4,377,584, 4,220,775, 4,760,071, 4,859,681 and 5,049,562 of Rasmusson et al. describe a group of 4-aza-17β-substituted-5α-androstan-3-ones which are said to be useful in the treatment of hyperandrogenic conditions. Specifically, U.S. Pat. No. 4,760,071 describes finasteride, which is 17β-(N-tert-butylcarbamoyl)-4-aza-androst-1-ene-3-one, also known as PROSCAR®, recently approved by the FDA for use in benign prostatic hyperplasia therapy.
U.S. Pat. No. 4,845,104 issued Jul. 4, 1989, to Merck & Co., discloses oxidized analogs of 17β-N-(monosubstituted)carbamoyl-4-aza-5α-androstan-3-ones having utility as highly potent testosterone-5α-reductase inhibitors and being metabolites resulting from in vivo administration of 7β-(N-t-butylcarbamoyl)-4-aza-5α-androst-1-en-3-one.
However, none of the cited references suggest that any of the novel- 17β-N-(monosubstituted) carbamoyl-4-aza-5α-androst-1-en-3-ones containing an aldehydes-substituted branched alkyl on the 17-position of the present invention would also be a metabolite or have utility in treating benign prostatic hypertrophy. In many cases, the metabolism of an active drug results in deactivation and/or excretion. However, in this case the compounds of the present invention maintain a high level of bioactivity in treated animals.
DESCRIPTION OF THE INVENTION
The present invention is concerned with compounds of the formula I: ##STR2## wherein the dotted line represents a double bond which can be present;
R 1 is hydrogen, methyl or ethyl,
R 2 is CONHC(CH 3 ) 2 CHO,
R' is hydrogen or methyl,
R" is hydrogen or β-methyl,
R'" is hydrogen, α-methyl or β-methyl,
Ra is methyl.
A preferred embodiment of the compounds applicable in the process of our invention is represented by the formula II: ##STR3## where R 1 is hydrogen or methyl and methyl groups of positions C-18 and C-19 are present.
The compounds of formula I of the present invention are prepared by a method starting with the known steroid of the formula 1 (See U.S. Pat. No. 4,845,104, issued Jul. 4, 1989, for its synthesis and properties): ##STR4##
See the following Flowsheet which illustrates the stages of: (1) oxidizing said starting material 1 with e.g. pyridinium chlorochromate to produce the corresponding compound 2 and, if desired; (2) alkylating the A-ring nitrogen to introduce an N-methyl or N-ethyl substituent onto the A ring by conventional methodology, e.g. methyl iodide and sodium hydride in DMF at room temperature to produce 3; and/or (3) reducing the A-ring double bond of 2 by catalytic hydrogenation over Pd/C in EtOAc at room temperature under a hydrogen atmosphere to produce 4; and then alkylating the Ring A nitrogen by the methodology above to produce 5, or catalytically hydrogenating the double bond of 3 to produce 5. Alternatively, 2 or 4 can be alkylated with ethyl iodide. ##STR5##
The compounds of the present invention, prepared in accordance with the method described above, are, as already described, potent and selective antiandrogens in the treatment of benign prostatic hypertrophy (BPH), by virtue of their ability to specifically inhibit testosterone-5α-reductase.
Accordingly, the present invention is particularly concerned with providing a method of treating BPH in human males by systemic or oral administration of the novel compounds of the present invention.
The present invention is thus also concerned with providing suitable topical and systemic pharmaceutical formulations for use in the novel methods of treatment of the present invention.
The compositions containing the compounds of the present invention as the active ingredient for use in the treatment of BPH can be administered in a wide variety of therapeutic dosage forms in conventional vehicles for systemic administration, as, for example, by oral administration in the form of tablets, capsules, solutions, or suspensions, of by intravenous injection. The daily dosage of the products may be varied over a wide range varying from 1 to 2,000 mg per person, preferably from 1 to 200 mg. and particularly preferred from 10 to 100 mg per person. The compositions are preferably provided in the form of scored tablets containing 0.1, 1, 5, 10, 25, 50, 100, 150, 250, and 500 milligrams of the active ingredient for the symptomatic adjustment of the dosage to the patient to be treated. An effective amount of the drug is ordinarily supplied at a dosage level of from about 0.01 mg. to about 50 mg./kg. of body weight per day. Preferably the range is from about 0.1 mg. to 7 mg./kgs. of body weight per day and more preferably from about 0.5 mg to about 20 mg/kg of body weight per day. These dosages are well below the toxic dose of the product. Capsules containing the product of this invention can be prepared by mixing an active compound of the present invention with lactose and magnesium stearate, calcium stearate, starch, talc, or other carriers, and placing the mixture in gelatin capsule. Tablets may be prepared by mixing the active ingredient with conventional tableting ingredients such as calcium phosphate, lactose, corn starch or magnesium stearate. The liquid forms in suitably flavored suspending or dispersing agents such as the synthetic and natural gums, for example, tragacanth, acacia, methyl-cellulose and the like. Other dispersing agents which may be employed include glycerin, and the like. For parenteral administration, sterile suspensions and solutions are desired. Isotonic preparations which generally contain suitable preservative are employed when intravenous administration is desired.
The method of preparing the novel compounds of the present invention, already described above in general terms, may be further illustrated by the following examples.
EXAMPLE 1
17β-N-(2-hydroxymethyl-2-propyl) carbamoyl-4-aza-5α-androst-1-en-3-one (1)
A mixture of 100 mg of 3-oxo-4-aza-5α-androst-1-ene-17β-carboxylic acid, 69 mg of dicyclohexylcarbodiimide and 77 mg of N-hydroxybenztriazole in 5 ml of methylene chloride was stirred at 0° C. for 30 minutes and then at 24° C. for 16 hours. To the resulting solution of activated ester was added 150 μl of 2-amino-2-methylpropanol. After 5 hours the mixture was filtered and the solid was rinsed with methylene chloride. The combined tiltrates were evaporated and the residue was chromatographed on silica coated thin layer plates (4, 1000 μ×20 cm×20 cm) with 8% methanol in chloroform. The major component was extracted and isolated. Recrystallization from acetonitrile-methanol gave 41 mg of the product, m.p. 282°-287° C.
EXAMPLE 2
17β-[N-(2-oxo-1,1-dimethylethyl)]carboxamido-4-aza-5 α-androst-1-en-3-one (2) ##STR6##
A suspension of 100 mg of the hydroxy steroid 1 in 4.0 ml of methylene chloride was treated with solid pyridinium chlorochromate (130 mg) portionwise at room temperature (RT). After stirring for 60 minutes, additional chlorochromate reagent was added (75 mg) and the mix was stirred for 2 hr more at RT. The supernatant from the reaction mixture was chromatographed by applying directly to 4×1000 μ×8"×8" silica plates and was eluted with 8% MeOH/CHCl 3 . The major component was isolated (42 mg). The solid was recrystallized from EtOAc/MeOH to yield 13 mg, m.p. 277°-279° C. of product 2. Additional 2 (56 mg) could be isolated by treatment of the tarry reaction residue with 5% NaOH solution, followed by filtration, aqueous washing and drying. | 17β-N-monosubstituted-carbamoyl-4-aza-5α-androst-1-en-3-ones of the formula: ##STR1## wherein the dotted line can represent a double bond when present,
R 1 is selected from hydrogen, methyl and ethyl and
R 2 is CONHC(CH 3 ) 2 CHO, and
Ra is methyl,
are described as being useful for the treatment of benign prostatic hypertrophy. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a weaving loom and more specifically to a circuit arrangement for a shuttleless weaving loom which facilitates accurate weft yarn dispensing.
2. Description of the Prior Art
A previously proposed weft yarn storage-supply arrangement for a weaving loom is shown in FIG. 1 of the drawings. In this arrangement weft yarn y is wound onto a drum 2 by a winding arrangement 3 and retained thereon by a retaining device 4. During picking the retaining device 4 is actuated to retract a blocking member 5 from a recess 6 formed in the drum 2 and permit a number of loops of weft yarn y to drawn axially off the drum. The amount of yarn y stored on the drum is controlled by a first sensor 7 which directs a beam of light against the drum and which, in response to the amount of light reflected therefrom, induces suitable energization of the winding arrangement 3 in a manner to maintain a predetermined length of yarn on the drum. The amount of yarn permitted to be released from the drum 2 during each picking operation is controlled by a second sensor 8 which, like the first, directs a beam of light against the drum 2 in a manner that the passage of weft yarn y across the point where the beam impinges on the drum 2, induces a change in the amount of light reflected and thus the output of the light receiving section of the second sensor 8. A control unit 9 is responsive to the output of the second sensor 8 and controls the operation of the retaining device 4.
However, the latter mentioned sensor arrangement has suffered from the drawback that when applied to high speed weaving machines wherein weft yarns having a diameter ranging from tens of microns to hundreds of microns, are exposed to the beam of light for only a few micro seconds, accurate detection of every loop being drawn off the drum becomes extremely difficult. Non-detection of one of more loops of weft yarn y being off the storage drum 4 of course invites an inevitable malfunction of the loom.
Further with this arrangement, even though the time for which the weft yarn is drawn off the storage drum arrangement is closely related to the actual weaving phase, the weft yarn withdrawing speed varies with the injection pressure, width of the fabric being woven, the type of thread being picked the speed at which the loom is being operated, etc., rendering it impossible to automatically set the thread retaining device actuation timing based on a predetermined weft yarn withdrawing speed. Viz., implementation of this type of control leads to the situation wherein the retaining device 4 tends to be actuated either too early or too late.
A full description of the above mentioned arrangement may be found in Japanese Patent Application Provisional publication No. Sho 57-29640 or corresponding U.S. Pat. No. 4,407,336 issued in the name of Steiner on Oct. 4, 1983.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a control arrangement via which the amount of thread such as weft yarn extracted from a storage device may be accurately predicted based on one or more sensed operating parameters and which accordingly finds utility in high speed weaving looms.
In brief, the invention features a circuit which receives a signal indicative of each loop of weft yarn being drawn off a cylindrical storage member and computes, based on this data, the time at which a retaining device should be controlled to terminate the release of loops of yarn from the storage member. The calculation includes an allowance for the time require for mechanical components associated with the releasing of the weft yarn from the storage device to actually reach a weft yarn release position and the time require for the calculation per se to be performed.
More specifically, the present invention takes the form of a device comprising a source of thread, a storage member onto which a plurality of loops of thread are wound for temporary storage prior use, an apparatus which draws off thread from said temporary storage member when energized, a first sensor for sensing the energization of said apparatus and outputting a signal indicative thereof, a retaining device for selectively permitting thread to be drawn off said temporary storge member, a second sensor for sensing the removal of each loop of thread removed from said storage member and outputting a signal indicative thereof, a circuit operatively connected with said first sensor, said second sensor and said retaining device, said circuit including means responsive to the signals outputted by said first and second sensors for computing the time for which said retaining device should be operated to permit loops of thread to be removed from said storage member.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the arrangement of the present invention will become more clearly appreciated from the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 shows the prior art arrangement discussed briefly in the opening paragraphs of the present application;
FIG. 2 is an elevational view of a weaving loom to which the present invention is applied;
FIG. 3 is a front elevational of a proximity switch arrangement forming part of the loom shown in FIG. 2;
FIG. 4 is a circuit in block diagram form showing an embodiment of the present invention; and
FIG. 5 is a timing chart showing the signals inputted to and outputted by the various elements shown in FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIG. 2 a loom arrangement to which the present invention may be applied is shown. In this arrangement a mounting bracket 10 forming part of a weaving loom frame 12 rotatably supports a hollow shaft 14 through which a weft yarn y is fed. One end of the shaft 14 is provided with a pulley 16 which is operatively connected with an electric motor 18 by a V-belt or the like 20. The other end of the shaft 14 is provided with an arm 22. This arm, as shown, is provided with an aperture 24 near the free end thereof through which the weft yarn y is threaded. It will be noted that the shaft 14 is provided with suitable apertures or through holes (not shown for simplicity of illustration) through which the weft yarn may be fed to the arm.
A temporary storage drum 26 is rotatably mounted on the end of the shaft through suitable roller bearings or the like. This drum is held stationary by weights or magnets (not shown) and further constructed of three or more segments which permit the diameter thereof to be varied and therefore the adjustment of the length of each loop of yarn stored thereon.
The drum 26 is also formed with a frusto-conical section 28 which is arranged with respect to the arm so that upon energization of the motor 18 the arm 22 rotates about the drum 26 to wind loops of weft yarn thereonto. The frusto-conical section 28 serves to induce the newly wound on weft yarn loops to slide along the drum toward a section 30 thereof, which tapers slightly in a direction away from section 28, during operation of the loom.
Located adjacent the periphery of the drum is a retaining device generally denoted by the numeral 32. As shown, this device includes an actuator 34 and a plunger 36 which is normally projected in a manner to be received in a recess 38 formed in the slightly tapered section 30 of the drum and thus prevent any of the loops of yarn y wound on the drum 26 from being removed therefrom. The plunger 36 is arranged to project through an aperture 40 formed in a cover 42 on which a weft yarn sensor 44 is mounted. Upon energization of the actuator 34 the plunger 36 is retracted into the aperture formed in the cover 42.
In this arrangement the weft yarn sensor 44 is arranged to emit a beam of light which impinges on the frusto-conical section 28 of the drum and which senses the presence of a predetermined amount of the weft yarn y stored thereon via either one of (a) using a drum having a highly reflective surface and detecting the reduction in reflection caused by the loops of weft yarn, or (b) using a non-reflective drum and sensing the increase in reflection induced by the weft yarns intercepting and reflecting the beam. The selection of the above mentioned alternatives of course is made in view of the colour and texture of the yarn being used in the loom.
A picking device generally denoted by the numeral 46 is mounted on the frame 12 in a manner to be essentially coaxial with the shaft 14 and drum 26. Interposed between the picking device 46 and the drum 26 is a guide 48. This guide is formed with an aperture 50 the center of which is essentially coaxial with the drum.
A proximity switch arrangement 52 is mounted on the loom frame. This switch comprises a stationary member 54 which includes therein a "Hall effect" switch or the like, and a movable element 56 fixed on a main shaft 58 of the loom. The movable member 56 is arranged to pass by the stationary member 54 either at, or in a timed relation with, the picking operation of the loom. The output of this switch is fed to a control unit 60 which also receives the output of the sensor 44.
A third sensor 62 is mounted on the cover 42. This sensor includes a light emitting section and light receiving section. The construction of this sensor 62 is such that the beam produced by the light emitting portion is reflected by the weft yarn as it slides, in this particular embodiment, over the periphery of the uniform diameter section 30 as it is drawn off the drum 26 and travels toward the guide 48. It should be noted that this sensor may be located in other suitable positions along the path traversed by the weft yarn as it travels toward the picking device 46. One example of same is given in the applicant's copending Japanese Patent Application No. Sho 57-217055.
A control circuit 70 (FIG. 4) forming part of the control unit 60, receives inputs from the proximity switch 52 and the sensor 62. This circuit includes a flip flop circuit 72 which receives the output of the proximity switch 52 on its "S" (set) terminal via a NOT circuit 74. The circuit further includes an amplifier 76 which receives and suitably modifies the output of the sensor 62. The output of this amplifier is fed to the SC (set count) terminal of a counter 78 which also receives a clock pulse input from an oscillator 80. The output of the counter 78 is fed the "R" (reset) terminal of the flip flop 72 via a computation circuit 82, a delay circuit 84 and a NOT circuit 86. The signal appearing on the "Q" output of the flip flop 72 is, as shown, fed to an amplifier 88 which suitably boosts the signal to a level suitable for energizing the actuator 34. The "Q'" terminal of the flip flop 72 is fed to the RS terminal of the counter 78 to reset same.
With this arrangement upon the proximity switch 52 sensing the initiation of a picking operation (see chart 5 (a)) the flip flop 72 is set by the leading edge of the pulse transmitted to the "S" terminal thereof to produce a high level signal on its "Q" output (see chart 5 (f)). This of course energizes the actuator 34 whereby the plunger 36 reaches a fully retracted position with a given delay as shown in chart 5 (g). Following sufficient retraction of the plunger 36 loops of weft yarn y are permitted to be drawn off the drum 26. The sensor 62 senses the passage of the yarn y therepast and outputs pulses (via the amplifier 76) as shown in chart 5 (b). The counter 78 is set by the leading edge of the first pulse produced by the sensor 62 whereby the counter 78 counts up under the influence of the input from the oscillator 80 until the leading edge of the next pulse. The output of the counter 78 (chart 5 (c)) is fed to the computation circuit 82 which takes the data indicating the time T required for one loop of weft yarn y to be taken off the drum 26, multiplies same by a predetermined constant A (for example the number of loops required minus 1), substracts the sum of the time required to perform the calculation per se (t 1 ) and the rise time of the actuator (t 2 ). Viz., the computation circuit calculates:
A×T-(t.sub.1 +t.sub.2).
The result of the calculation is used to trigger the delay circuit 84 which upon the expiry of the calculated period issues a pulse (see chart 5 (e)) which resets the flip flop 72 so that the signal appearing on the Q terminal falls to a low level and that appearing on the Q' terminal rises to a high level clearing the counter 78 in readiness for the next picking cycle.
It will be appreciated that the functions performed by the above described control circuit can also be carried out by a microprocessor which can be programmed to, if desired advantageous, accept only data which falls within a predetermined range. Viz., ignore data which is approximately double the normal time required for the extraction of one loop from the storage drum; and/or keep a predetermined amount of data stored so as to ascertain with precision the time required for one loop to be taken off the storage arrangement.
In summary, the present invention features an arrangement wherein the time interval between two successive loops of weft yarn being drawn off the storage drum arrangement is determined and used as a basis for estimating the length of weft yarn picked and for calculating the time at which the weft yarn retaining device should be controlled to terminate the release of weft yarns. This permits the variation in traction force produced by the picking device, the length of yarn required, the type of yarn being picked, etc., to be taken into account on a cycle to cycle basis and therefore accurate control of the yarn release irrespective of minor fluctuations in operational parameters and the like. | A circuit receives a signal indicative of each loop of weft yarn being drawn off a cylindrical storage member and computes based on this data the time required for a given number of loops to be drawn off. The calculation includes an allowance for the time required for mechanical components associated with the releasing of the weft yarn from the storage device to actually reach a weft yarn release position and the time required for the calculation per se to be performed. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to the formation of compound yarn products and, more particularly, but not by way of limitation, it relates to an improved form of craft yarn which is constructed by bundling a plurality of individual yarns within a zig-zag stitch.
2. Description of the Prior Art
The prior art includes numerous types of multi-yarn or multi-filament craft yarns that are constructed variously by braiding, weaving, pressing, knitting, felting, crocheting, etc. in order to construct a yarn having particularly desirable qualities for a specific decorative or functional purpose. An early U.S. Pat. No. 1,755,018 teaches an unusual form of flat rope that comprises a plurality of longitudinally extending strand wires, the number depending upon requisite flexibility, which are essentially braided along the length. U.S. Pat. No. 4,356,690 teaches construction of a fasciated yarn constructed to have a high strength, the yarn comprising a staple fiber group having specialized staple composition. The fasciated yarn includes a bundle of linearly arrayed interior fibers which are then spirally wrapped by an outer yarn. A similar type of wrap is employed on carpet tufting yarns made in accordance with U.S. Pat. No. 3,639,807 wherein metallic thread is spirally wound oppositely to the spiral lay of the fiber yarn.
Still other prior art yarns of the multi-strand filament type are represented by the teachings of U.S. Pat. Nos. 4,100,725 and 3,568,426. These teachings relate to entangled types of yarns wherein entanglement is carried out in accordance with a prior set pattern to provide a heavier and stronger product. Finally, U.S. Pat. No. 3,477,220 teaches yet another form of novelty yarn and method for making wherein the finished yarn becomes a tangled multi-filament strand, the entanglement carried out in a vortex cell.
SUMMARY OF THE INVENTION
The present invention relates to a method of constructing a unique form of craft yarn which is suitable for large scale commercial production in any of a multitude of selected sizes, strand number, resiliency and other qualities characteristic of the process. In addition, the craft yarn can be readily produced by the home economist with merely a zig-zag sewing machine or attachment, such yarn being constructible in any of the various sizes and textures for use in various craft undertakings, sewing, tailoring, millinery uses and the like. The craft yarn is constructed by selecting a plurality of individual yarns, threads, filaments, or the like for parallel lay beneath the presser foot of a zig-zag stitching mechanism. Thereafter, zig-zag stitch length and bite width are adjusted, again in accordance with desired final qualities of the craft yarn, and the zig-zag stitch is run along the bundle thereby to encase the bundle and form the craft yarn.
Therefore, it is an object of the present invention to provide a method for readily constructing a versatile craft yarn.
It is also an object of the present invention to provide a method for making an improved craft yarn using no more than sewing equipment that is normally to be found around the home.
It is yet further an object of the present invention to provide a method for forming craft yarns having diverse variation in size, rigidity, color and texture.
Finally, it is an object of the present invention to provide a readily constructible craft yarn which is versatile in usage yet vastly more economical to construct or produce in quantity than comparable yarns.
Other objects and advantages of the invention will be evident from the following detailed description when read in conjunction with accompanying drawings which illustrate the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the method steps in constructing a craft yarn in accordance with the present invention;
FIG. 2 is a perspective view showing a zig-zag stitch mechanism with yarn bundle being fed therebeneath;
FIG. 3 illustrates schematically the layout of the zig-zag stitch length and bite relative to the encased bundle; and
FIG. 4 is an idealized view of a portion of craft yarn constructed in a accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention may be utilized, particularly by the home craftsman or hobbyist, to produce multi-filament craft yarns of a wide range of selected sizes, textures, colors and degrees of rigidity. Thus, in FIG. 1, selection of yarns at step 10 is made in accordance with the desired finally-constructed yarn. The materials available for construction of craft yarn include sewing thread, embroidery flosses, monofilament yarns, O-twist yarns, novelty yarns, knitting yarns, crocheting yarns, lightweight cords, candlewicking yarns and any of a wide number of the basic yarns or linear textile structures. Having selected a yarn, the craftsman next selects a suitable thread for zig-zag encasement of the yarns and this input is provided through stage 12 as the selected thread is threaded into the zig-zag sewing machine 14. Encasement of the yarns by the thread is carried out in the sewing machine 14 to produce the output craft yarn as indicated at stage 16.
FIG. 2 illustrates the process during construction of a craft yarn 18 from a bundle of individual yarns 20 as they pass beneath the zig-zag presser foot 22 for encasement by opposite-side thrusts of sewing needle 24. The selected finished yarns 20 are laid parallel and then twisted slightly so that the group of yarns can be easily placed under the presser foot 22 of the sewing machine. After the group of yarns is placed under the presser foot, the foot is lowered and, with zig-zag bite and stitch length adjusted, stitching proceeds with group of yarns 20 held taut while being carried under presser foot 22 by the feed dog as the zig-zag stitching encases the yarns into a bundle forming the craft yarn 18. FIG. 3 shows schematically the progression along a yarn bundle 20 by the progressive stitch or points 26 laying the zig-zag thread 28 therealong. FIG. 4 shows more pictorially the essential craft yarn construction as the threads 28 encase the bundle of yarns 20.
Many variables are available in constructing the craft yarns. First, the selection of the basic yarn 20 may vary from a few strands of a very fine thread up to a great number, e.g. 36, 45, or greater number of thin strands, or they may be several strands of a very heavy knitting yarn or the like. The bundled yarn is then encased by the outer zig-zag thread which again may be varied widely between great limits as to color, size and type of thread. In addition to the basic yarn variables, the operator then has the choice of bite or the side-to-side needle spacing, as well as the stitch length, i.e., the longitudinal stitch spacing. Variation of the bite and stitch length is directly related to the resiliency of the craft yarn; that is, the ability of the yarn to be bent and take a set versus a generally resilient character. In any event, a large number of different forms and textures of craft yarn can be produced using the present method of construction and utilizing the wide range of variables. Generally, the stitch length control is most closely related to the final crispness of the craft yarn and its ability to be molded or shaped. During the construction, the pressure being applied by the presser foot 22 should be considered and adjusted to best accommodate the particular numbers and sizes of yarns being processed. Proper thread tension must be evident.
The foregoing discloses a novel method of constructing a craft yarn that has a large number of characteristics or attributes each of which may be varied for specific exigencies in the process of making. The craft yarn may be constructed most economically in any and all sizes and textures for use in a multitude of craft, sewing, millinery, flower decor and many other undertakings wherein cord-like material of specific size, rigidity, color and the like is required, e.g. button loops or belt loops in sewing and tailoring work. The skilled craftsman can soon learn to make craft yarn strands to fit many applications simply by adjusting the variables as to yarn texture, size and the bite and stitch length of the zig-zag encasement thread.
Changes may be made in combination and arrangement of elements as heretofore set forth in the specification and shown in the drawings;
It being understood that changes may be made and embodiments disclosed without departing from the spirit and scope of the invention as defined in the following claims. | A method of forming a craft yarn having unique properties and a wide variation of physical characteristics, and consisting of a selected plurality of parallel-laid yarns encased along their length by a zig-zag stitch of selected thread. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 07/780,282; filed Oct. 22, 1991, now abandoned.
FIELD OF THE INVENTION
This invention relates generally to automated devices which provide a plurality of degrees of motion, such as articulated lifting devices and the like, and more specifically to improvements in the structures and controlling systems for such devices.
BACKGROUND OF THE INVENTION
Various devices have been developed for the lifting or other movement of relatively large and/or bulky articles. A particular area of need for such devices is in the field of aviation, where such devices are generally used for loading ordnance and external stores on military aircraft, and for the installation and removal of engines from various civil and military aircraft.
Most such devices are essentially lifting platforms, and as such any motion in the horizontal plane must be provided by moving the vehicle upon which the lifting platform or device is installed. Even in those lifting devices which also provide for motion in the horizontal plane, such horizontal motion is generally provided along only a single axis. No such devices are known which provide for motion in any direction in the horizontal plane as well as along the vertical axis, and further provide angular or rotational motion as well, in the manner of the present invention.
It will be appreciated that such a device would result in a considerable savings of labor, as well as increasing safety to a great degree. Aircraft engines particularly have a variety of mounting points which must be precisely aligned with the cooperating points in the aircraft, and the inaccurate placement of the engine in the lifting device may result in a great deal of difficulty in the installation of the engine in the aircraft if that engine is supported by a lifting device which does not provide for motion in all of the generally accepted six degrees of motion. Indeed, a tragic accident occurred in 1979 due to the inadequacies of engine lifting devices, when a jet engine physically separated from the remainder of an air carrier aircraft on takeoff from Chicago's O'Hare Airport. The cause was determined to be a damaged mount on the engine due to a fork lift being used to support and transport the engine for installation on the aircraft. While procedures were in place to prevent such damage, the devices used with those procedures were, and still are, cumbersome, difficult, and time consuming to use.
The need arises for improvements in lifting and/or motion translation devices which improvements will provide for linear and angular motion along and about all three axes, thus providing six degrees of motion. An important feature of such a device is to provide for the recording of the forces and torques involved in operation over a period of time, in order to show evidence of the operating procedures used in a given operation should a question arise subsequently. The improvements must further provide for easy operation by a single person using a simple controlling device, which device should provide positive pressure feedback to the operator in order for the operator to more accurately sense the forces and torques involved.
DESCRIPTION OF THE RELATED ART
J. A. Munn et al. U.S. Pat. No. 2,944,331 discloses an engine installation frame for use with larger jet aircraft engines. The device fails to meet many of the above needs, as it provides for only manual adjustment in only a single plane. If alignment is off along another axis, the entire frame (which does not provide for any horizontal motion) or aircraft must be moved for realignment.
P. Karnow et al. U.S. Pat. No. 3,087,630 discloses an automated omnidirectional manipulating device for use in military aircraft ordnance handling. The device provides an extended arm capable of providing motion along and about various axes, but operates in a completely different manner than that used by the present invention. Moreover, the control means is located immediately adjacent the ordnance and no means is provided for alternative control locations.
E. R. Peterson U.S. Pat. No. 3,288,421 discloses a movable and rotatable platform which is supported by a series of six linearly adjustable struts. This device is generally known as a "Stewart Platform," after a developer of the general concept. While the present invention is generally based upon this concept, several improvements are disclosed which extend beyond the original basic device. Further, no remote control or feedback means is provided in the above patent.
S. Hansen U.S. Pat. No. 3,952,979 discloses a vibration isolator which is based upon the geometric principles involved in the Stewart Platform. While the six struts between the upper and lower plates are adjustable in length, it is not clear how the device is operable as no means is provided for angular displacement of each of the struts as its length is varied. Thus, the device provides only extremely limited displacement between the two plates.
J. R. Colston U.S. Pat. No. 4,216,467 and J. M. M. Whitehead each disclose hand controller units which are generally based upon the Stewart Platform principle of operation. These two devices do not provide for any feedback pressure from the apparatus being controlled, but rather provide transducer devices within each interconnecting strut which transmit electrical signals dependent upon either the force (Colston) or the displacement (Whitehead) applied to the struts.
Finally, G. Shelef U.S. Pat. No. 4,819,496 discloses a manipulator device for robotic use. The geometric arrangement of the actuator struts is not similar to the present invention, and other differences are noted.
None of the above noted patents, either singly or in combination, are seen to disclose the specific arrangement of concepts disclosed by the present invention.
SUMMARY OF THE INVENTION
By the present invention, an improved apparatus capable of providing general linear and general angular motion is disclosed.
Accordingly, one of the objects of the present invention is to provide such an improved apparatus which is capable of handling relatively heavy materials and objects, such as military aircraft external stores and large turbine engines, with adequate safety and accuracy.
Another of the objects of the present invention is to provide such an apparatus which may be remotely controlled and operated.
Yet another of the objects of the present invention is to provide a controller for such an apparatus which operates using the same geometric arrangement as that of the material handling apparatus itself.
Still another of the objects of the present invention is to provide feedback means to the apparatus controller and record a time history of that feedback.
A further object of the present invention is to provide a plurality of means for the attachment of the struts to the opposing plates of both the apparatus and the controller.
With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel combination and arrangement of parts hereinafter more fully described, illustrated and claimed with reference being made to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmented perspective view of a strut assembly of the present invention, showing an upper and lower end bearing arrangement.
FIG. 1A is a side view in section of the strut assembly of FIG. 1, showing the internal arrangement.
FIG. 2 is a side view in section of an alternative strut end or bearing arrangement.
FIG. 3 is a side view in section of an internal strut position sensing device.
FIG. 4 is a schematic diagram of the arrangement of the struts of the lifting apparatus and of the controller.
FIG. 5 is a perspective view of the controller.
FIG. 6 is a block diagram of the system.
FIG. 7 is a partially broken perspective view of an alternative strut showing the general arrangement and attachment means.
FIG. 8 is a side view in section of another alternative strut actuation and attachment means.
FIG. 9A is a perspective view of the omnidirectional lifting apparatus in use, shown in combination with an additional lifting apparatus.
FIG. 9B is a perspective view of the basic apparatus of FIG. 9A being used as an ordnance or external stores lift.
Similar reference characters designate corresponding parts throughout the several figures of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, particularly FIGS. 9A and 9B of the drawings, the present invention will be seen to relate to an omnidirectional material handling or lifting device, generally noted as 10, and various improvements in the operation and structure of such a lift 10 as shown further in the various remaining drawings. Lift 10 will be seen to comprise a lower platform 12 and an upper platform 14, which platforms 12 and 14 are separated by a geodetic array of six struts 16a through 16f. It should be noted that while additional struts 16 may be used, that the arrangement of six struts shown constitutes the minimum number required in order to provide the six degrees of freedom of movement required for such a lifting device 10.
Struts 16a through 16f may be considered to be arranged in a hexagonal pattern when viewed from either directly above or below, as shown in the schematic of FIG. 4. The letters a through f of FIG. 4 denote the corresponding positions of lift struts 16a through 16f shown in FIG. 9A. The arrangement of the attach points for struts 16a through 16f shown in FIG. 4 results in a triangulated configuration for the upper ends and the lower ends of struts 16a through 16f. However, it will be recognized that of course the upper and lower surfaces of any such device may take on any desired shape, so long as the attach points for struts a through f form the general arrangement shown in FIG. 4.
This same general arrangement may also be applied to the configuration of struts 18a through 18f in controller apparatus 20 of FIG. 5, which will be discussed in detail further below, or in combination with other types of strut mechanisms such as the electrically actuated strut 17 of FIG. 8. It will also be seen that struts 16a through 16f alternately extend between lower platform 12 and upper platform 14 of lift 10, and further take on the same general arrangement in any such similar device as shown in the schematic of FIG. 4 or as in the arrangement of controller 20 of FIG. 5. While the schematic view of FIG. 4 shows a common series of attach points for each pair of strut ends in order to provide a simplified figure, it will be understood that separate attach points are necessary for each end of each strut as shown in FIGS. 9A, 9B and 5.
A single strut 16 of the type shown in FIG. 9A is disclosed in FIG. 7. Strut 16 will be seen to be telescopically extendible by means of inner rod end 26 which is concentric with and passes into outer end 28. Strut 16 may be hydraulically or pneumatically actuated by means of line 32, or other alternative means such as electromagnetic actuation may be used as in the case of strut 17 of FIG. 8.
FIG. 8 discloses one possible type of electromagnetically actuated strut 17. Strut 17 basically comprises an inner central rod 36 and an outer concentric tube 38, in a manner similar to other known telescoping struts. Tube 38 contains electromagnetic coils 40 which form a solenoid, which is powered by cable 42. Power may be applied to coils 40 by means of cable 42 in order to attract or repel central rod 36, in order to actuate strut 17. The direction of current flow through coils 40 will determine attraction or repulsion of rod 36, and the amount of current flow will determine the force applied.
It will be seen that as any one or more struts 16a through 16f, 17a through 17f, or 18a through 18f are extended or contracted, provision must be made for both horizontal and vertical angular changes in their positions. Various alternative attachment means may be used to provide for such angular changes, such as the trunnion attachment points 30 shown in FIGS. 9A and 9B or 31 as shown in FIGS. 1 and 5, spherical joints 34 shown in FIG. 8, or the coplanar joint shown in FIG. 2. In any case, each end of each strut 16, 17 or 18 must be provided with an attachment point to the appropriate surface, which attachment point must allow at least a reasonable degree of horizontal and vertical angular movement (two degrees of freedom) for the captured end of any strut 16, 17 or 18. It is also critical that any attachment system for these struts provide for any forces on the strut to be in a purely axial direction, and that all torsional forces to the struts themselves be eliminated. The various attachment methods disclosed herein provide for such purely axial force.
An example of a trunnion 30 may be seen more clearly in FIG. 7. In order to provide for both horizontal and vertical angular motion, trunnion 30 provides for both a horizontal axis 44 and a vertical axis 46 providing for angular motion of strut 16. Trunnion 30 will be seen to comprise a base plate 48 and two parallel upwardly extending side plates 50. Side plates 50 provide for placement of horizontal axis 44, while base plate 48 provides for placement of vertical axis 46. Vertical axis 46 may also provide for the securing of trunnion 30 to upper or lower platform 12 or 14 by means of vertical axis 46.
Spherical joints 34 may also be used as an alternative means of attachment of struts 16 or 18 to upper and lower platforms 12 and 14. Spherical joints 34 may be contained within sockets 52, which sockets 52 may in turn be attached to upper and lower platforms 12 and 14 to serve in place of trunnions 30. Preferably, such spherical joints 34 would be used for applications in which the bearing loads would be lower, such as in controller 20, while trunnions 30 would be used for attach points for struts 16 in larger scale and heavier duty devices, such as lift 10. However, it is understood that either method may be used to provide attach points for the struts 16 or 18 for either controller 20 or lift 10, and further that either type of strut 16 or 18 may be used in either controller 20 or lift 18.
A further strut attachment means is disclosed in FIG. 2. The various other attachment means each require the various attachment axes to be located outside of the planes of the upper or lower platforms. This requirement is obviated by the coplanar attachment means shown in FIG. 2. In this figure, a plate 118 which may comprise either an upper or lower surface for the attachment of struts 16, is line bored in the planar axis in three places, as at bore 120. These three bores 120 each serve as a first pivotal axis for two struts 16 or 17. Closed yokes 122 are mounted to provide a second pivotal axis 126 for each strut end, which axis 126 is 90 degrees to the first pivotal axis 124 defined by bores 120. A third degree of freedom is provided in this arrangement by the capability of the upper end 26 of a strut 16 or 17 to rotate within the outer end 28 of the strut 16 or 17.
It will be seen that the above attachment structure provides advantages in the compact attachment for such struts 16 and 17, by means of the two intersecting revolute areas provided by first and second pivotal axes 124 and 126. However, no means is provided by those two intersecting revolute areas for rotational movement along the axis defined by the strut 16 or 17 centerline. However, the inherent capability of such struts to allow rotation of the rod end 26 within the remaining strut body 28 will provide the required third rotational axis and necessary degrees of freedom for the proper operation of such a mechanism.
FIGS. 1 and 1A disclose additional devices providing for the necessary degrees of freedom, as well as providing for the extendible operation of such struts. Struts 18 of FIGS. 1 and 1A are actuated by means of an internal cable system, and may be used in combination with a controller apparatus 20 as shown in FIG. 5, or alternatively may be used to operate other lifting devices such as platform 10 shown in FIG. 9A. In fact, such a cable actuated system may prove to be desirable in areas where the possibility of hydraulic fluid leakage could cause unacceptable contamination, or for other reasons.
The trunnions 31 which provide for two degrees of freedom of motion, also provide signal output means for the relative extension of struts 18. Trunnion 31 comprises a fixed base 74, which base 74 provides for a pivotal attachment 76 to a housing 78. Housing 78 contains a potentiometer or other device (not shown) capable of measuring the rotation of a shaft 80, which shaft 80 passes through housing 78 at a 90 degree angle to the axis of pivotal attachment 76 in order to provide the required two degrees of freedom of movement. A strut attachment fitting 82 secures the lower end of strut 18 to housing 78 by means of pivots 84.
The opposite end of strut 18 is equipped with a gimbaled fitting comprising an inner ring 86 and an outer ring 88 which are pivotally joined by inner and outer axes 90 and 92, which axes 90 and 92 are at right angles to one another. This gimbal assembly 86 through 92 is in turn supported in an outer bearing ring 94, which ring 94 allows the axial rotation of the outer gimbal ring 88 therewithin.
Further rotational freedom is provided for gimbal assembly 86 through 92 by means of cap 95 which is secured to the upper end 96 of strut 18. Cap 95 serves to capture a flange 97 at the base of gimbal rod 99, which flange 97 is supported by bearings 101 between the inner portion of cap 95 and the upper end 96 of strut 18. The two rotational degrees of freedom serve to permit the two axes 90 and 92 of gimbal assembly to rotate as necessary about the longitudinal axis of strut 18, insuring that the two axes 90 and 92 providing for angular displacement of the upper end 96 of strut 18 are free to rotate relative to strut 18 and the attachment (not shown) for outer ring 94. Thus, the inherent limitations of such gimbal assemblies which comprise two perpendicular axes allowing angular displacement, are avoided by the four degrees of freedom provided. These four degrees of freedom, in combination with the two provided by trunnion 31, provide the required freedom for any upper and lower platforms attached to the gimbal assembly and trunnion and the strut secured therebetween.
Strut 18 provides positional information by means of a cable mechanism enclosed therein. FIG. 1A discloses the interior of strut 18: housing 78 and strut base 74 have been deleted from FIG. 1A for greater clarity. Strut 18 contains a cable 100 which is secured within the interior of the upper end of upper strut portion 96 at a point 102 on or very near the axial centerline of strut 18. Cable 100 extends downward from attach point 102 to shaft 80, and is wrapped with a plurality of turns 104 about shaft 80. Cable 100 then extends upward to pass around lower strut portion crossmember 106, and thence downward to finally attach to upper strut crossmember 108. Opposing slots 110 are provided in the sides of upper strut portion 96 in order to clear lower strut crossmember 106.
It will be seen that this arrangement will result in cable 100 causing shaft 80 to rotate as the upper and lower ends 96 and 98 of strut 18 are extended or retracted, as in the case of the operation of a controller 20 using struts 18. Thus, the position indicating means within housing 78 will be actuated, thereby providing positional information relating to the extension of strut 18. The resulting signal may be used to actuate a lifting device such as lift 10, or alternatively strut 18 may be used as an actuating strut rather than a controlling strut by means of electrical, hydraulic or other motors housed within housing 78 to drive shaft 80 in order to actuate strut 18.
The above mechanism has one limitation in that it does not permit the upper portion 96 and lower portion 98 of strut 18 to rotate axially relative to one another. It will be further evident from the description of trunnion 31 that no axial rotary motion is permitted in strut 18 relative to trunnion 31. Hence, the provision for axial rotation by outer bearing ring 94 surrounding the remaining gimbal assembly 86 through 92, as well as the apparatus permitting axial rotation by means of components 95, 97, 99, and 101, is needed for such a strut 18. It will be seen that the four degrees of freedom provided by the apparatus at the upper end 96 of strut 18, in combination with the two degrees of freedom provided by the trunnion apparatus at the lower end 98 of strut 18, serve to provide the required minimum of six degrees of freedom allowing for complete axial and rotational movement of such a strut 18 relative to the upper and lower attach points, as noted above. Other strut assemblies, such as the hydraulic or pneumatic strut 16 shown in FIG. 7 and the electrically actuated strut 17 shown in FIG. 8, provide for the axial rotation of one strut end relative to the other; therefore no additional provision is needed for axial rotation at one strut end attach point.
However, the struts 16 and 17 also possess the limitation that they do not inherently provide positional information as to the extension of the two strut ends relative to one another, as does strut 18 described above. Due to this limitation, it is necessary to provide additional means to determine the extension of the ends of struts 16 and 17 relative to one another. Preferably, such positional sensing means should be internally contained within the struts, in order to preclude the fouling of any external components or linkages or backlash or play in any external linkage which may be required. The internal transducer 112 shown in FIG. 3 of the drawings provides for this. Transducer 112 includes a coil 114 which is connected to an electrical power supply by lines 116. Transducer 112 is inserted within a strut such as a hydraulic strut 16, having inner and outer cylindrical components 26 and 28 as shown in FIG. 7. Transducer 112 operates as the inductance in coil 114 changes, due to the changing proximity of the walls of strut component 26 as strut 16 is extended or retracted. The changes in the inductance of coil 114 are transmitted by means of lines 116 to controller and recorder 20 for processing. It will be apparent that such an internal transducer 112 may also be installed within other types of struts 17 or 18, particularly in such a strut as 17 shown in FIG. 8, in order to determine the extension of such a strut.
Lift 10 is shown in combination with an additional parallel arm lifting device 54 in FIG. 9. Such a device 54 may be used to carry lift 10 and further to serve as a mounting bed for lower platform 12 of lift 10, rather than mounting a wheel and axle assembly directly to lower platform 12 of lift 10. Parallel arm lift 54 comprises a lower platform 56, which is in turn supported by a plurality of wheels 58 in order to provide mobility. Parallel arms 60a through 60d (60d is not visible due to the perspective of the drawing) are secured to parallel arm lift platform 56, and may be actuated by hydraulic or other means known in the art. Lift arm trunnions 62 or other suitable means may be used to secure the bases of parallel arms 60a through 60d to parallel arm lift platform 56, and it will be appreciated that a similar means may be used to secure the upper ends of arms 60a through 60d to the lower surface of lower platform 12 of lift 10.
It will be appreciated that the forces involved in the operation of lift 10 may possibly be on the order of several thousand pounds. Thus, some form of power supply and servo unit 64 will be necessary. Power supply/servo 64 may comprise a prime mover such as a gasoline or diesel engine and a hydraulic pump and/or electrical generator. Such power supplies are known in use with other electrically or hydraulically powered devices and the exact construction of power supply/servo 64 is not claimed as a novel feature of the present invention, but only as a power source for that invention. Power supply/servo 64 may be installed with lift 10, parallel arm platform 54, or remotely, and provide power to operate lift 10 and/or parallel arm platform 54 by means of hydraulic or other power lines 66.
Controller 20 is used to provide precise input to power supply/servo 64 by means of transmission cables 66. Transmission cables 66 provide an input signal or signals to power supply/servo 64, which signal is processed by power supply/servo 64 to provide output power to lift 10 by means of power cable 68. As the force output (either hydraulic or pneumatic pressure or electrical current) by power supply/servo 64 is directly related to the load to be maneuvered, thus greater loads will require greater force, no return signal of the force received by lift 10 is required. However, an indication of the force required as well as positional information for each strut must be provided to controller 20, in order for an operator to be able to sense the required forces. This may be accomplished by means of a proportional regulator which transmits some small fraction of the forces developed by power supply/servo 64 back to controller 20 by means of cable 42, in order to provide feedback for the operator of controller 20. Again, the forces transmitted via the various cables or lines 42. 66 and 68 may be by means of either electrical or hydraulic power or possibly by some other means not discussed. It is also desirable to record a history of the forces and positions involved in the operation of the struts and apparatus in order to provide a record of the operation in the event of a mishap or some later question involving the particular operation. This may also be easily accomplished by means of the input and output signals to controller/recorder 20.
It will be seen that the operation of lift 10 with controller 20 is a relatively simple procedure for the operator, due to the essentially smaller scale nature of the mechanism of controller 20 in comparison to lift 10. As controller 20 is essentially a reduced scale duplication of lift 10, it follows that any movement of the upper platform 70 of controller 20 by control stick 72 will result in a proportional movement of lift 10. As both lift 10 and controller 20 are capable of six degrees of freedom of motion (longitudinal, lateral and vertical displacement and angular motion about each of those axes), an operator of controller 20 may readily relate to whatever motions are required in order to maneuver a load, such as an engine E as shown in FIG. 9A or ordnance O as shown in FIG. 9B. Moreover, as a lift is begun and the forces required are increased, the forces supplied by power supply/servo unit 64 may be detected by a proportional regulator and transmitted back to controller 20 by means of cable 42 in order for the operator to develop a feel for the amount of force or torque required for a given operation. Such a system is inherently useful in the precise positioning of large, bulky and heavy objects, such as aircraft engines and ordnance.
It is to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims. | A powered material handling apparatus or lift provides for the movement and positioning of large, heavy and/or bulky objects using six degrees of freedom of motion. The lift may be used for the handling of virtually any such materials, but is especially suited for the handling of such objects as jet aircraft engines and aircraft external stores. The lift may be remotely operated by a hand controller which is mechanically arranged in the same manner as that of the lift, through a power supply and servo device. Feedback may be provided to the hand controller by the power supply and servo device, thus enabling the operator of the control to sense the forces occurring at the lift as it is actuated. Additionally, provision is made for the recording of a history of the forces, torques and linear actuation of the struts of the apparatus in the event of some subsequent question regarding a particular operation. Further improvements in such devices include various methods of attachment of the lifting struts to the platforms of the lifting apparatus, as well as several methods of strut actuation and sensing of the linear position of the struts. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of copending application Ser. No. 569,684, filed Jan. 10, 1984, which in turn is a continuation-in-part of copending application Ser. No. 551,372, filed Nov. 10, 1983.
BACKGROUND OF THE INVENTION
This invention relates to a novel high molecular weight atrial peptide having useful natriuretic, diuretic and vasodilating activity.
It is known that the cells of the atrial myocardium in mammals contain numerous membrane-bound storage granules. These characteristic secretory granules, which have been observed in the rat, dog, cat and human atria, resemble those which are in peptide-hormonal producing cells. See DeBold et al., J. Histochem. Cytochem. 26, 1094-1102 (1978). It has been reported that crude tissue extracts of atrial myocardium when injected intravenously into non-diuretic rats produced a rapid and potent natriuretic response. See DeBold et al., Life Sciences 28, 89-94 (1981). Partial purification of rat atrial homogenates with a brief boiling step and fractionation on Sephadex® was achieved by Trippodo et al., Proc. Soc. Exp. Biol. Med. 170, 502-508 (1982). Natriuretic activity was found by these investigators in the overall molecular weight range of 3600 to 44,000 daltons and in peptide fractions of both the higher molecular weight range of 36,000-44,000 daltons and a lower molecular weight range of 3600-5500 daltons.
Rat atrial extracts also have been fractionated into low molecular weight fractions (<10,000 daltons) and high molecular weight fractions (20,000-30,000 daltons) both of which in vitro relaxed smooth muscle and were potent natriuretic agents when administered intravenously to rats. See Currie et al., Science 221, 71-73 (1983).
In other recent publications, a number of scientists have disclosed various low and intermediate weight atrial natriuretic peptides having amino acid sequences in the range of from about 19 to 59 amino acids. Thus, DeBold et al., Fed. Proc. 42(3), Abstract 1870, page 611 (1983), report the purification of an atrial natriuretic peptide having a molecular weight of 5150 daltons and a sequence of 47 amino acids which the investigators designated "Cardionatrin I". Three additional peaks with natriuretic activity were obtained by high performance liquid chromatography (HPLC) procedures.
In a later publication, Grammer et al., Biochem. Biophys. Res. Commun. 116(2), 696-703, Oct. 31, 1983, disclose the partial purification of a rat atrial natriuretic factor having a molecular weight of approximately 3800 and containing 36 amino acid residues.
In still more recent publications, Flynn et al., Biochem. Biophys. Res. Commun. 117(3), 859-65 (Dec. 28, 1983), and Kangawa and Matsuo, Ibid., 118(1), 131-39 (Jan. 13. 1984), disclose atrial natriuretic peptides of the rat and human, respectively, having sequences of 28 amino acids.
Thibault et al., FEBS Letters 167, 352-56 (1984), disclose the purification of an intermediate molecular weight atrial natriuretic peptide having 73 amino acids, and Kangawa et al., Biochem. Biophys. Res. Commun. 119(3), 933-40 (1984), disclose the purification of an intermediate molecular weight beta-rat atrial natriuretic peptide having 48 amino acids.
In applicant's co-pending applications Ser. No. 551,372, filed Nov. 10, 1983, and Ser. No. 569,684, filed Jan. 10, 1984, atrial peptides of low molecular weight having from about 19 to about 24 amino acids are disclosed and claimed. Several of these peptides are further disclosed by a research group led by the present applicant, Currie et al., Science 223, 67-69 (1984).
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the present invention, a novel high molecular weight peptide is provided which exhibits useful natriuretic, diuretic and vasodilating activity. This biologically active peptide has the following amino acid sequence: ##STR2##
In the peptide structure, the amino acid components are designated by conventional abbreviations as follows:
______________________________________Amino Acid Abbreviated Designation______________________________________L-Alanine AlaL-Arginine ArgL-Aspartic acid AspL-Asparagine AsnL-Cysteine CysL-Glutamic acid GluL-Glutamine GlnGlycine GlyL-Histidine HisL-Isoleucine IleL-Leucine LeuL-Lysine LysL-Methionine MetL-Phenylalanine PheL-Proline ProL-Serine SerL-Threonine ThrL-Tryptophane TrpL-Tyrosine TyrL-Valine Val______________________________________
The peptide material of this invention has been isolated in a partially purified form which did not exist in the rat myocardium from which it was initially obtained. That is, it has been prepared in a form which is essentially free of low molecular weight peptides, and free from other cellular components and tissue matter. This new atrial peptide has physiological characteristics which suggest that it is important to medical science in the study of the endocrine system of the cardiac atria with respect to humoral agents for modulation of extracellular volume, sodium and vascular resistance.
In particular, the novel peptide of this invention has therapeutic use as a diuretic, natriuretic, renal vasodilator and smooth muscle relaxant. That is, it is effective on sodium, urine volume, renal vasodilation and smooth muscle tone.
In brief, this novel peptide has been obtained by fractionation of rat atrial extracts by gel filtration chromatography to provide a high and a low molecular weight fraction, both of which had useful natriuretic activity. The lower molecular weight fraction was separated and purified into several low molecular weight atrial natriuretic peptides as described in the aforesaid copending applications of the present inventor.
The high molecular weight fraction (atriopeptigen-APG) obtained by the aforesaid gel filtration chromatography of rat atrial extracts was fractionated in accordance with the present invention by isoelectric focusing and reverse phase HPLC to obtain a partially purified APG. Purification of cyanogen bromide digests of the partially purified high molecular weight fraction resulted in the isolation of a single biologically active cyanogen bromide cleavage peptide of 93 amino acids comprising amino acids 19 to 111 of the above APG. Sequence analyses of these peptides coupled with recent reports of sequence analyses of intermediate molecular weight atrial peptides [Thibault, et al. FEBS Letters 167, 352-356 (1984), and Kangawa, et al., Biochem. Biophys. Res. Commun. 119, 933-940 (1984)] provide the complete primary structure of the above 111 residue APG.
DETAILED DESCRIPTION OF THE INVENTION
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter regarded as forming the present invention, it is believed that the invention will be better understood from the following detailed description of preferred embodiments of the invention. For convenience, the cited references are listed at the end of this detailed description.
By gel filtration chromatography, the natriuretic and diuretic activity of rat atrial extracts has been found in high (20,000-30,000) and low (less than 10,000) molecular weight fractions which also display smooth muscle spasmolytic activity (in vitro) (1). It was concluded by the present inventor that the high molecular weight fraction is the precursor of the low molecular weight fraction in view of the effects of partial proteolysis with trypsin. Trypsin treatment of the high molecular weight fraction markedly increased spasmolytic activity. The active products, which comigrate with the low molecular weight fraction on gel filtration (2), are atriopeptins I, II and III (3) by reverse phase HPLC. Therefore, the active components of the high molecular weight fraction have been designated as atriopeptigens (APGs), precursors of the atriopeptins (APs), the low molecular weight bioactive atrial peptides. These atriopeptins comprise the following partial sequences of the full 111 amino acid atriopeptigen as described in the above copending applications of the inventor:
AP I=amino acids 88 to 108;
AP II=amino acids 88 to 110; and
AP III=amino acids 88 to 111.
In the purification of the high molecular weight atrial peptides and their derivatives, a smooth muscle bioassay of each fraction after activation by partial tryptic proteolysis was carried out (1,2). The active fractions contain the sequence of the low molecular weight atriopeptins (3). The first step in purification of the high molecular weight fraction (obtained by G-75 Sephadex chromatography) was isoelectric focusing which showed this to be a mixture of bioactive species (apparent isoelectric points at pH 4.91, 5.01, 5.17, 5.34, and 6.03). The bulk of bioactive species (between pH 4.6 and 5.4), after removal of Ampholytes and sucrose, was subjected to reverse phase HPLC. The typical chromatogram showed a complex mixture of bioactive peptides clustered at 31 and 34% acetonitrile. Of these, one predominant component was of sufficient purity by gel analysis (apparent molecular weight 17000) and was selected as an atriopeptigen for further purification and characterization in accordance with the present invention.
In view of the complexity of the atriopeptigens compared to the singular sequence of the atriopeptins derived from them, it was concluded by the present inventor that the atriopeptigens may, in turn, be derivatives of some larger peptide. Accordingly, the effects of chemical cleavage were examined. Cyanogen bromide cleavage was selected because of the lack of methionine in the low molecular weight atriopeptin sequence (5). Cyanogen bromide cleavage occurs at the methionine in position 18 of the full 111 amino acid sequence of the atriopeptigen to provide a high molecular weight peptide fragment of 93 amino acids. The initial step in the fractionation of a cyanogen bromide digest of the total high molecular weight fraction produced a bioactive material (found at 30-31% acetonitrile) which was purified by reverse phase HPLC to yield a single component by HPLC having an apparent molecular weight of 9500 by gel electro-phoresis.
Sequence data for both peptides are shown below. Overlapping the sequences of these peptides and those of Thibault et al., FEBS Letters 167, 352-6 (1984), and Kangawa et al., Biochem. Biophys Res. Commun. 119, 933-40 (1984), provides the primary structure of a 111 residue atriopeptigen. The results of C-terminal analysis are consistent with this. Carboxypeptidase treatment of the APG rapidly removed Phe without release of detectable Tyr or Arg. On the other hand, similar treatment of the cyanogen bromide cleavage peptide afforded rapid release of Tyr, Arg, and Phe (Table 1), thereby indicating that this preparation consists of three peptides having the same sequences which terminate in Tyr, Arg, and Phe.
This sequence of 111 amino acid residues incorporates at its C-terminus the low molecular weight peptides which have been recently described (underlined in the sequence, below) in conjunction with a pair of basic amino acid residues (Arg-Arg in this case) which typically form the cleavage site in a variety of precursors of secreted peptides and proteins. ##STR3##
In the above, the complete primary structure of the 111 amino acid atriopeptigen was deduced from: A amino acid sequence of the first 34 residues of the atriopeptigen, B amino acid sequence of the first 39 residues of the cyanogen bromide cleavage peptide, C amino acid sequence of "intermediate M r form atrial natriuretic factor" (11) and D complete amino acid sequence of "beta-rat atrial natriuretic polypeptide" (12).
TABLE 1______________________________________Carboxyl-terminal sequence analysis ofcyanogen bromide cleavage peptideAmino Acid pmol of productResidue 20 sec 2 min 10 min 60 min______________________________________Tyr 10 18 45 62Arg 23 26 55 74Phe 26 27 65 89______________________________________
The following examples describe the purification, partial characterization, and the natriuretic, diuretic and vasodilating activity of the above component (111 amino acids) of the high molecular weight (20,000-30,000) fraction and of a cyanogen bromide peptide fragment (93 amino acids) derived from this fraction.
EXAMPLE 1
Preparation of an atriopeptigen--An extract of atria from 1200 rat hearts was prepared and subjected to chromatography on G-75 Sephadex by general procedure as previously described (3). The high molecular weight fraction was lyophilized, dissolved in pH 4-6 Ampholine carrier ampholytes (LBK Instruments, Inc., Rockville, Md.) and electrofocused in a 110 ml sucrose density gradient column (LKB) at 1000 V for 40 hours (4). The column then was emptied at 48 ml per hour, collecting 2 ml fractions. Following determination of pH, aliquots (50 μl) of column fractions were adjusted to pH 8 (by addition of 450 μl 0.1 M tris buffer, pH 8.4) and incubated with trypsin (Sigma Chemical Co., St. Louis, Mo., one unit per ml) for 1 hour at 22°. These preparations were assayed for chick rectum relaxation activity by general procedure as previously described (1,2). Combined column fractions (pH 4.6 to 5.4) containing the bulk of the bioactivity (˜ 30 ml) were chromatographed on G-50 Sephadex (80×2.7 cm) in 0.5M acetic acid to remove Ampholytes and sucrose. Following freeze drying, this material was subjected to reverse phase HPLC using the Brownlee RP-300 Aquapore column and solvent system previously described (3). The gradient consisted of (a) 0 to 24 percent A for 8.8 minutes, (b) 24 to 28 percent A for 25 minutes, (c) 28 to 36 percent A over 100 minutes. Aliquots (50 μl) of HPLC column fractions (2 ml) were dried in vacuo, taken up in 500 μl 0.1M tris, pH 8, trypsinized and bioassayed as above.
Preparation of a cyanogen bromide peptide from the high molecular weight fraction--The lyophilized high molecular weight fraction obtained by chromatography on G-75 Sephadex from an extract of atria from 600 rat hearts (1,3), dissolved in 10 ml 70% formic acid, was added to 500 mg cyanogen bromide (Eastman Organic Chemicals, Rochester, N.Y.) in a glass stoppered tube (5). After 16 hours (at 22°) 90 ml water was added and the solution was lyophilized. The residue was subjected to reverse phase HPLC using the system described above, with (a) 0 to 27.2 percent A in 10 minutes followed by (b) 27.2 to 32 percent A in 60 minutes. Bioactive fractions (obtained at 29.6 to 31.2 percent A) were taken to dryness in vacuo and purified by a second protocol using a mixture of solvent A' (0.1 percent trifluoracetic acid in propanol-1) and B (0.1 percent trifluoracetic acid in water) at 0.67 ml per minute consisting of (a) 0 to 15 percent A' for 5 minutes, followed by (b) 15 to 24 percent A' for 90 minutes. Bioactive fractions (at 22 to 22.5 percent A') were taken to dryness in vacuo and then subjected to a third protocol using solvents A" (0.085 percent phosphoric acid in propanol-1) and B" (0.085 percent phosphoric acid in water) at 0.67 ml per minute, consisting of 0 to 50 percent A" for 50 minutes. The bioactive product (obtained at 32.1 percent A") was then put through HPLC twice again using the second protocol above, finally yielding 110 μg (protein) of a single bioactive component (detected at 215 nm) at 22.1 percent A'.
Analysis of Peptides
Amino acid analysis was performed by hydrolysis of 1 nmol peptide in 6N HCl for 22 hours at 110°. The hydrolysate was lyophilized and applied to a Waters amino acid analysis system utilizing o-phthalaldehyde precolumn derivitization (6) followed by reverse phase HPLC.
Peptide sequencing--N-terminal sequencing was performed by sequential Edman degradation of 2-4 nmol peptide using an Applied Biosystems model 470A gas phase sequencer (7), detecting phenylthiohydantoin derivatives by HPLC (8). Average repetitive yields exceeded 93%. C-terminal sequencing was performed by addition of carboxypeptidase Y (2 μg, 20 μl, Pierce Chemical Co., Rockford, Ill.) to 1-2 nmol peptide dissolved in 280 μl of 50 mM sodium acetate buffer, pH 5.5. At intervals, 50 μl aliquots were added to 25 μl 1% trifluoracetic acid (9) and the amino acids released were determined by amino acid analysis (as above).
Gel analysis--Electrophoresis of peptides (1-2 μg) was done with a 15% polyacrylamide gel (0.4% bis acrylamide) according to Laemmli (10). The gel was stained with 0.8% silver nitrate for 20 minutes, washed, and developed with a solution of 0.005% citric acid and 0.2% formaldehyde.
EXAMPLE 2
The cyanogen bromide high molecular weight rat atrial peptide purified as described in Example 1, above, was tested for natriuretic activity in dogs.
The high molecular weight peptide was either injected alone or after trypsin treatment. The trypsin (1 unit/ml) incubation was performed for 60 min at room temperature with 100 μg of the purified cyanogen bromide high molecular weight peptide. Atriopeptin I and II were purchased from Peninsula Labs, San Carlos, Calif. Atriopeptin III and Ser-leu-arg-arg-Atriopeptin III (the Flynn et al. peptide, reference 13) were synthesized by automated peptide syntheses.
Mongrel dogs, either sex, were anesthetized (i.v.) with pentobarbital sodium (30 mg/kg). A flank incision for a retroperitoneal exposure of the right kidney was performed. The ureter was cannulated with PE160 (Clay Adams) tubing which was connected to a fraction collector for urine recovery. An electromagnetic flow probe (8 mm diameter Carolina Instrument) was placed around the right renal artery for the measurement of renal blood flow. A 22 guage needle (attached to PE50 tubing and syringe) was inserted into the renal artery above the flow probe. The dog was continuously infused with saline (0.9% NaCl) at 1.3 ml/min. Urine samples were collected at 5 min intervals and analyzed for volume, sodium, potassium, and osmolarity. The peptides were injected (i.a. in the renal artery) at 30 min intervals.
Results
The high molecular weight (cyanogen bromide) peptide produced a concentration dependent diuresis which was not significantly altered by trypsinization. The threshold response (a 50% increase in urine volume) was achieved with 0.3 nmoles while a 450% increase in urine flow was achieved with 3 nmoles. Comparison of the amount of peptide needed to produce a 200% increase in urine volume indicates that ser-leu-arg-arg-APIII requires 0.3 nmoles; high molecular weight+trypsin requires 0.5 nmoles, high molecular weight alone 0.7 nmoles; atriopeptin II and III require 10 nmoles; and atriopeptin I at 30 nmoles only increased urine volume 50%. The rank order potency for vasodilation comparing the dose needed to produce an increase of 20 ml/min of renal blood flow is an follows: ser-leu-arg-arg-APIII required one nmole; the cyanogen bromide high molecular weight peptide (in the presence or absence of trypsin pretreatment) required 3 nmoles; atriopeptin III required 8 nmoles; atriopeptin II required 17 nmoles; while 30 nmoles of atriopeptin I only produced a 6 ml/min change in renal blood flow. Each peptide was tested in 3-5 separate dogs.
In summary, direct injection of the purified cyanogen bromide fragment of the high molecular weight atriopeptigen produced a pronounced diuresis indistinguishable from the most potent of the low molecular weight peptides. This may reflect an instantaneous conversion of the peptide in the kidney or direct recognition by the kidney of the intact peptide. The disparity in the rank order potency of the peptides in terms of renal vasodilation versus natriuresis suggests that these responses are mediated by separate receptors. Substantially similar diuresis was obtained when the partially purified 111 amino acid atrio-peptigen (before cyanogen bromide cleavage) was tested in dogs.
The following references cited in the above detailed description of the invention for disclosure of published procedures are incorporated herein by reference.
REFERENCES
1. Currie et al., Science 221, 71-73 (1983).
2. Currie et al., Proc. Natl. Acad. Sci. 81, 1230-1233 (1984).
3. Currie et al., Science 223, 67-69 (1984).
4. Geller et al., Biochem. J. 127,865-874 (1972).
5. Gross and Witkop J. Biol. Chem. 237, 1856-1860 (1962).
6. Hill et al., Anal. Chem. 51, 1338-1341(?) (1979).
7. Hunkapiller et al., Methods Enzymol. 91, 399-413 (1983).
8. Hunkapiller and Hood, ibid., 486-493.
9. Hayashi, Methods Enzymol. 47, 84-93 (1977).
10. Laemmli, Nature 227, 680-685 (1970).
11. Thibault et al., FEBS Letters 167, 352-56 (1984).
12. Kangawa et al., Biochem. Biophys Res. Commun. 119, 933-40 (1984).
13. Flynn et al., Biochem. Biophys. Res. Commun. 117, 859-65 (1983).
Various other examples will be apparent to the person skilled in the art after reading the present disclosure without departing from the spirit and scope of the invention and it is intended that all such further examples be included in the scope of the invention. | A novel atrial peptide having useful natriuretic, diuretic and vasodilating activity is disclosed with the following amino acid sequence: ##STR1## | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 10/182,102, filed Apr. 11, 2003, which is a U.S. National filing under §371 of International Application No. PCT/GB01/00227, filed Jan. 22, 2001, which claims priority from British Application No. 0001388.8, filed Jan. 22, 2000, all of which are incorporated herein by reference.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
TECHNICAL FIELD
[0003] This invention relates to methods for treating textiles, and, more particularly to treating textiles with enzymes.
BACKGROUND OF THE INVENTION
[0004] Enzymes are widely used in textile treatments, for example in industrial processing such as desizing of cloth and stonewashing of denim, or to impart enhanced fabric properties such as pilling properties and hand. Enzymes are also used in domestic laundry products to assist in cleaning soiled and stained fabrics and to counter the appearance of surface fibre. In particular, cellulases have been used to treat cellulosic, particularly cotton goods and specific enzyme activities can be tailored for producing specific effects, whilst reducing or avoiding deleterious effects.
[0005] Enzyme treatment is carried out on textiles using a variety of methods and machinery. Rotary dyeing machines, winches, jet dyeing machines and drum washers are all in widespread use and have the common feature that the textile is subjected to a high degree of agitation over a prolonged period of time. Many of the more desirable effects, such as defibrillation are only fully achievable when the textile is subject to significant mechanical action and even abrasion during processing.
[0006] Treatment conditions during enzyme treatment are carefully controlled, both as to pH and temperature. Generally, treatment is carried out at somewhat elevated temperature, around 45-55.degree. C., in a solution of which the pH is in the range 4.8-5.5 for acid cellulase systems, or 4.8-8 for neutral enzymes.
[0007] Enzyme treatment of cellulosic goods invariably leads to a reduction, even if only a slight reduction, in fabric properties such as tensile or tear strength, and there is also a measurable weight loss involved, which is partly due to the mechanical agitation involved in the processing.
SUMMARY OF THE INVENTION
[0008] The present invention provides new processes for textiles, notably cellulosic textiles such as cotton and flax, which enhance their properties in ways not previously contemplated in the context of enzyme treatment, and which do not adversely affect textile properties to the same extent as conventional enzyme treatment.
[0009] The invention comprises, in one aspect, a method for treating textiles comprising applying to the textile an enzyme having a specific activity towards the textile under conditions such that there is substantially no mechanical agitation.
[0010] An enzyme-containing composition may be applied to the textile by soaking or by padding, for example. The enzyme composition may be left in contact with the textile for an extended period of time under ambient conditions, for example, for five hours or more, even up to ten or twenty hours.
[0011] The textile may subsequently be washed to remove unreacted enzyme.
[0012] An important effect of this treatment is to improve the dimensional stability particularly of cotton and other cellulosic fabrics, such as flax, and viscose rayon. Enzymes found to be particularly useful in this regard are cellulases such as Biotouch L, cellulase F or cellulase H, all commercially available from Rohm Enzyme Finland OY, or mixtures or any two or all three thereof. Other enzymes, some yet to be developed, will be found useful, these, however, being the most advantageous investigated to date.
[0013] The enzyme may be applied at an add-on of 0.1 to 10 mg total protein per gram of textile.
[0014] The textile may comprise more than one fibre type, and may indeed comprise blends of cellulosic and non-cellulosic fibres, for example cotton-polyester blends. Where more than one fibre type is involved, the enzyme system may comprise more than one enzyme so as to have specific activities specific activity towards different fibres types.
[0015] Textiles which can be treated include woven and knitted fabrics as well as non-wovens and even yarns. Fabrics may be treated by cold batch padding, the treatment being carried out over prolonged periods, or simply by soaking. Yarns may be treated on hank or shein or even on the package, just being left to soak at room temperature for up to twenty hours or longer.
[0016] After the enzyme treatment is finished, the cellulolytic reaction may be stopped by immersing the textile in a 5% solution of sodium carbonate, and the textile may then be rinsed, for example, three times, with agitation, then dried in whatever manner is appropriate.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 is a graph showing the percentage improvement in dimensional stability versus percentage tear strength in the warp direction of an RS fabric batched for 17 hours with a 0.2, 1.0 and 5.0 mg of Biotouch L, cellulase F and cellulase H per gram of fabric at different pick-up rates;
[0018] FIG. 2 is a graph showing the percentage improvement in dimensional stability versus percentage tear strength in the warp direction of an RS fabric batched for 17 and 48 hours with a 0.2, 1.0 and 5.0 mg of Biotouch L, cellulase F and cellulase H per gram of fabric at pick-up rate of 65%.
DETAILED DESCRIPTION
[0019] The invention will now be described with reference to the following Examples:
EXAMPLE 1
[0020] The cellulases Biotouch L (a Trichderma reesei secreted cellulase, commercially available from Rohm Enzyme Finland OY), cellulase F and cellulase H (from the same supplier) were applied to a 100% cotton fabric woven from ring spun yarns (205 g/m) with a heavy-duty padder. Each enzyme was applied in solution at three different add-ons, namely 0.2, 1.0 and 5.0 mg of total protein per g of fabric, and was buffered with 0.1M acetate buffer, pH adjusted to 5.0 with sodium hydroxide. The pick-up rate was (65.+−0.5) % (percentage weight of enzyme liquor per weight of fabric). The fabrics were then rolled up and kept rotating for 17 hours at ambient temperature (approx. 20.degree. C.). The cellulolytic reaction was then stopped by immersion in a 5% solution of sodium carbonate and the fabric rinsed in three consecutive cycles, without detergent, the first rinse in water at approximately 60.degree. C., agitated for 10 minutes, the second in warm water (40.degree. C.) agitated for five minutes, the third in cold water, agitated for five minutes, after which the fabrics were dried.
[0021] Dimensional stability of the fabrics to further washing was determined on the basis of area change by the method ISO 5077:1984, the enzyme treatments being compared to a buffer treated control. Three samples of each of the treated fabrics were washed in a domestic washing machine with ECE standard detergent on a 40.degree. C. cycle for up to ten times, each wash being followed by tumble drying for 70 minutes. Tear strength tests (Marks & Spencer tear strength method) were also carried out.
[0022] There was a significant improvement in the dimensional stability on all cellulase treated fabrics compared to the buffer treated control. The greater improvements in dimensional stability were obtained with cellulase F; treatments with cellulases Biotouch L and H gave lower dimensional stability with greater loss in fabric strength. The treatment with 5.0 mg of cellulase F/g of fabric at 65% pick-up resulted in an improvement in shrinkage of about 29% with a loss of strength of about 5.5%. The results are summarised in FIG. 1 .
EXAMPLE 2
[0023] As for Example 1, but with the fabric being rotated for 48 hours instead of 17 hours. Again, cellulase F gave best results, but the prolonged reaction time resulted in considerably higher strength losses with little or no improvement in shrinkage—see FIG. 2 .
EXAMPLE 3
[0024] On denim fabrics, the treatments according to Example 1 showed cellulase F, again, to give best results, a lighter denim fabric having an improvement in shrinkage of about 25% with a strength loss of only 4.5%, a heavier fabric registering an improvement in shrinkage of about 35% with a loss of strength of only 3.3%.
EXAMPLE 4
[0025] A cotton interlock fabric treated as in Example 1, but with a pick-up rate of 80% showed with cellulase F at 5.0 mg/g an improvement in shrinkage of about 53% with a strength loss of 6.1%.
EXAMPLE 5
[0026] A 50%/50% cotton/polyester bed linen fabric treated as in Example 1 at 70% pick-up showed a 53% improvement in shrinkage on treatment with cellulase F (5.0 mg/g) with a loss of strength of 5%.
EXAMPLE 6
[0027] A 100% viscose fabric treated as in Example 1 showed a 30% improvement in shrinkage with a strength loss of about 6.3% when treated with cellulase F at 50 mg/g.
[0028] Generally speaking, cellulase F outperformed cellulases Biotouch L and H, though they too showed useful improvements in shrinkage with somewhat greater loss of strength. Clearly, different enzymes will have different effects on different fibres, and other enzymes may yet be discovered to outperform cellulase F.
[0029] Treatment with enzymes without agitation for the purpose of improving dimensional stability may be carried out as a pre- or post-treatment to treatment with other enzymes for improving other properties under the usual elevated temperature and agitation conditions.
[0030] The method may not be limited to cellulosic fibres. Enzymes exist that have effect on other natural fibres, such as wool, and enzymes may be found to have similar effects on synthetic fibres.
EXAMPLE 7
[0031] Bleached ecru cotton yarn ( 1/20 Nm count) was wound onto a dye spindle for a Pegg yarn package sample dyeing machine. Four spindles were prepared, three for treatment with enzyme, the other as a control.
[0032] The prepared control yarn package was loaded in the sample dyeing machine. Water containing sodium acetate buffer to give a pH value of 5.0-5.5 (prepared from acetic acid and sodium hydroxide) was circulated at 40.degree. C. The machine was set to automatically reverse the flow through the package every five minutes, and the treatment was continued for eight hours. At the end of the treatment process, the yarn package was rinsed in a solution of sodium carbonate (at a concentration of 1 g/l) at 80.degree. C. for ten minutes, then rinsed twice with warm (50.degree. C.) water and cold water. The yarn package was removed and dried in a radio-frequency dryer.
[0033] Further yarn packages were treated as above, but a quantity of Enzyme F was included in each treatment, equivalent to 0.2, 1.0, 5.0 mg enzyme protein/g of yarn. Each treatment was carried out as described above.
[0034] The dried yarns were knitted on a hand-knitting machine to give suitable fabrics. The dimensions of each fabric square were measured before and after washing and tumble drying in a domestic washing machine. The treated fabrics showed a significant reduction in dimensional change (shrinkage) amounting to 10%, 15% and 32% respectively for the treatment levels 0.2, 1.0, 5.0 mg protein /g yarn. | There is disclosed a method for treating textiles comprising applying to the textile an enzyme having a specific activity towards the textile, under conditions such that there is substantially no mechanical agitation. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to machines used for scarifying, abrading and generally treating the surface of roadways, and more particularly, to a road-cutting apparatus which can be intermittently actuated automatically, as the apparatus moves along the road surface, to create spaced impressions or grooves in the roadway surface while allowing manual compensation for cutter wear.
2. Description of the Prior Art
On the shoulders along roadways, it is frequently a desired option to cut impressions or grooves extending laterally across the shoulder-to act as a warning for drivers that they have moved off the main roadway. When the tires of the vehicle contact the grooves, a noise is heard and vibration is felt which alerts the driver that the tires are in contact with the shoulder. Alternatively, ridges may be laid along the shoulder. In either case, the warning effect is the same, and such devices are frequently referred to as “rumble strips.”
The spacing of these grooves varies depending upon the locale. For example, some states may use a different spacing than others. Also, in some areas, it is desired to use a larger spacing between groups of grooves. For example, there may be a group of a specific number of grooves which have a relatively small spacing therebetween and then a much larger space between the next set of grooves of that specific number. Generally, this type of spacing is referred to as intermittent cutting.
One prior art device utilizes a cam-like wheel which engages the surface, and as the device moves along the roadway, the cam rotates. This causes a cutter wheel to be alternately lowered into cutting contact with the road surface and raised out of contact. By moving this device along the road surface, a plurality of spaced grooves may be formed. This device has the disadvantage of not easily accommodating intermittent cutting. Also with the cam device, the spacing between adjacent grooves can only be controlled by changing the cam. There is no quick adjustment available. The present invention solves this problem by providing an apparatus which uses a microprocessor to control the spacing between adjacent grooves, and the microprocessor can also be programmed to provide a preset, larger spacing between sets of grooves to allow automatic intermittent cutting.
Another prior art device uses a hydraulic cylinder which raises and lowers the cutter into contact with the road surface. Such a device is disclosed in U.S. Pat. No. 5,415,495. This device has the disadvantage of requiring a highly specialized vehicle of which the cutting apparatus is an integral part. It is not adapted for use with common vehicles, such as farm tractors. The present invention solves this problem by providing a self-contained apparatus which can easily be pulled behind any number of known vehicles, such as farm tractors.
A cutter drum assembly for cutting grooves or impressions in a road surface is disclosed in U.S. Pat. Nos. 5,046,890; 5,129,755; 5,236,278; and 5,378,080. This, or other types of rotary cutters, may be utilized in the apparatus of the present invention.
The present invention also provides an apparatus which can be conveniently moved along a road surface when not in operation but can be quickly and easily placed into an operating position when desired, while at the same time providing automatic cutting of the grooves and also providing control of the cutter to compensate for wear thereon.
SUMMARY OF THE INVENTION
The present invention is an apparatus for cutting impressions or grooves in a road surface. The apparatus generally comprises a tool carrier adapted for moving along the road surface, a rotatable cutter positioned adjacent to the tool carrier, a cutter positioning means for positioning the cutter between a raised position spaced from the road surface and an operating position adjacent to the road surface, and a cutter operating means for alternately moving the cutter into and out of cutting engagement with the road surface after the cutter is in the operating position thereof A transport wheel is attached to the tool carrier and has a transport position engaging the road surface and a retracted or raised position spaced from the road surface. A wheel actuation means is used for moving the transport wheel between the transport and retracted positions thereof.
The wheel actuation means comprises a transport control arm pivotally connecting the transport wheel to the tool carrier and a transport cylinder connect to the tool carrier and the transport control arm, whereby the transport control arm and the transport wheel may be pivoted with respect to the tool carrier.
The cutter positioning means comprises a positioning control arm pivotally attached to the tool carrier and a positioning cylinder interconnecting the positioning control arm and the cutter whereby the cutter may be pivoted between the raised and operating pistons thereof The cutter positioning means may be used for pivoting the cutter with respect to the tool carrier for compensating for wear on cutting elements on the cutter.
The cutter operating means comprises an operating control arm attached to the cutter and an operating cylinder interconnecting the positioning control arm and the operating control arm whereby the cutter may be engaged and disengaged with the road surface. The cutter operating means is adapted for pivoting the cutter with respect to the tool carrier when moving the cutter between cutting engagement with the road surface and disengagement therefrom.
The apparatus further comprises an elevating wheel connected to the cutter for supporting the cutter on the road surface when the cutter is in the operating position thereof and when the cutter is cuttingly engaged with the road surface. The elevating wheel is connected to the positioning control arm and pivotable therewith.
Preferably, the apparatus further comprises a means for measuring a distance the tool carrier is moved along the road surface and generating a signal in response thereto and a logic controller actuating the cutter operating means in response to the signal. This may be used to control the width and depths of the grooves or impressions and also the spacing therebetween. It may also be used to control the longer spacing between groups of grooves or impressions during intermittent cutting.
Numerous objects and advantages of the invention will become apparent as the following detailed description of the preferred embodiment is read in conjunction with the drawings which illustrate such embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the road-treating apparatus of the present invention in a transport position for movement along a road surface prior to treatment thereof.
FIG. 2 shows the road-treating apparatus in an operating position in which the cutter is adjacent to the road surface.
FIG. 3 illustrates the road-cutting apparatus of the present invention in a cutting position for providing spaced grooves along the road surface.
FIG. 4 is a schematic of the logic control circuit used in the apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and more particularly to FIG. 1, the road-cutting apparatus of the present invention is shown and generally designated by the numeral 10 . Apparatus 10 comprises a frame or tool carrier 12 which in the illustrated embodiment is adapted for connection to a vehicle 14 by a trailer hitch 16 of a kind known in the art at a forward end 18 of the tool carrier. An advantage of apparatus 10 is that vehicle 14 can be almost anything, for example, a farm tractor. A specialized vehicle 14 is not required. Alternatively, apparatus 10 can be a self-contained vehicle with its own power source (not shown) on board.
A transport wheel 20 is positioned adjacent to a rearward end 22 of tool carrier 12 . In the preferred embodiment, a pair of transport wheels 20 are utilized and positioned at generally opposite lateral sides of the apparatus. Wheel 20 is of a kind generally known in the art and preferably has a tire 24 thereon and is rotated about an axle 26 . Axle 26 is connected to a rear portion 28 of a first control arm 30 . First control arm 30 may also be referred to as transport control arm 30 . An intermediate portion 32 of transport control arm 30 is connected to rear end 22 of tool carrier 12 by a pivot 34 .
Transport control arm 30 also has a forward portion 36 . A first hydraulic cylinder 38 , also referred to as a transport cylinder 38 , has one end thereof attached to forward portion 36 of transport control arm 30 at a pivot 40 . The other end of transport cylinder 38 is connected to a cylinder bracket 42 by another pivot 44 . Cylinder bracket 42 is fixedly attached to tool carrier 12 .
A control arm bracket 46 is fixedly attached to tool carrier 12 . A second control arm 44 is attached to control arm bracket 46 by a lower pivot 50 . Second control arm 48 may also be referred to as a positioning control arm.
A second hydraulic cylinder 52 has one end attached to positioning control arm 48 by an upper pivot 54 . Second hydraulic cylinder 52 may be referred to as positioning cylinder 52 . The other end of positioning cylinder 52 is attached to a cylinder bracket 55 by a pivot 56 . Cylinder bracket 55 is fixedly attached to tool carrier 12 .
A third hydraulic cylinder 58 is attached to positioning control arm 48 by an intermediate pivot 60 . Third hydraulic cylinder 58 may also be referred to as an operating cylinder 58 . The other end of operating cylinder 58 is connected to an upper portion 62 of a third control arm 64 by a pivot 66 . Third control arm 64 may also be referred to as an operating control arm 64 . The maximum extension and retraction of operating cylinder 58 may be controlled as further described herein.
Operating control arm 64 is connected to a cutter frame 68 by a pivot 70 . Cutter frame 68 is connected to, or forms a portion of, a cutter housing 72 . A cutter drum assembly 74 is disposed in cutter housing 72 and rotatably mounted on cutter frame 68 by a cutter shaft 76 . Cutter shaft 76 , and thus cutter drum assembly 74 , may be rotated by a prime mover 78 . Prime mover 78 may be of any kind known in the art, such as a hydraulic motor, an internal combustion engine, an electric motor, etc.
Cutter drum assembly 74 itself is a prior art device comprises a cutter drum 80 with a plurality of cutter elements 82 attached to the outer surface thereof. Cutter elements 82 may be of any kind known in the art and are preferably replaceable and interchangeable with other cutter elements so that they may be easily replaced as desired.
A lower portion 84 of operating control arm 64 extends downwardly and forwardly from pivot 70 . An elevation wheel 86 is rotatably connected to lower portion 84 of operating control arm 64 by an axle or shaft 88 . Preferably, there are two laterally spaced elevations wheels 86 generally aligned with the ends of cutter drum assembly 74 .
A measuring wheel 100 is rotatably mounted on a shaft or axle 102 and attached to tool carrier 12 , such as by bracket 104 . A distance counter wheel 106 is also mounted on shaft 102 and is rotatable with measuring wheel 100 which is always engaged with road surface 90 . Distance counter wheel 106 is part of a logic control circuit 108 which includes electronic and hydraulic components.
Referring now to FIG. 4, the details of logic control circuit 108 are shown. A magnetic proximity switch 110 is positioned adjacent to distance counter wheel 106 , and is adapted to detect the movement of cogs 112 on the distance counter wheel as they move past the proximity switch. Magnetic proximity switch 110 is connected to a distance logic controller 114 by wires 116 .
A first cylinder proximity switch 116 is connected to controller 114 by wires 118 , and a second cylinder proximity switch 120 is connected to controller 114 by wires 122 . As will be further described herein, first cylinder proximity switch 116 and second cylinder proximity switch 122 are adapted to sense the presence of rod end 124 of operating cylinder 58 when positioned thereto. The longitudinal positioning of first cylinder proximity switch 116 and second cylinder proximity switch 120 may be adjusted longitudinally with respect to operating cylinder 58 , and as will be further described herein, this allows control of the stroke of operating cylinder 58 and thus the cutting position of cutter drum assembly 74 .
A three-position electric solenoid hydraulic valve 126 is connected to controller 114 by wires 128 and 130 . Hydraulic valve 126 is hydraulically connected to operating cylinder 58 by hydraulic lines 132 and 134 . Hydraulic valve 126 is connected to a hydraulic pump 136 by a line 138 . Hydraulic pump 136 is hydraulically connected to a hydraulic reservoir 140 by a line 142 . A hydraulic suction filter 144 may be used with line 142 . Hydraulic pump 136 may also be referred to as operating hydraulic pump 136 .
A hydraulic return line 146 extends from hydraulic valve 126 to reservoir 140 .
Another hydraulic pump 148 which may be referred to as transport hydraulic pump 148 is connected to reservoir 140 by a line 50 and a hydraulic suction filter 152 . Hydraulic pump 148 is connected to a transport control valve 154 by a line 146 . Transport control valve 154 is hydraulically connected to transport cylinder 38 by lines 158 and 160 . A hydraulic return line 162 extends from transport control valve 154 to reservoir 140 . Transport control valve 154 is illustrated as a manual or hand valve, but could also be an electronic solenoid valve.
A further hydraulic pump 164 , which may also be referred to as positioning hydraulic pump 164 , is connected to reservoir 140 by a line 166 and another hydraulic suction filter 168 . Positioning hydraulic pump 164 is connected to a positioning control valve 170 by a line 172 . Positioning control valve 170 is hydraulically connected to positioning cylinder 52 by lines 174 and 176 . A hydraulic return line 178 extends from positioning control valve 170 to reservoir 140 . Positioning control valve 170 is illustrated as a manual or hand valve, but could also be an electronic solenoid valve.
While control circuit 108 has been illustrated as mounted on apparatus 10 , it could also be mounted on vehicle 10 or at any other location which would be convenient for the operator of the apparatus. Also, while three different hydraulic pumps 136 , 148 and 164 have been shown, it will be seen by those skilled in the art that one or more of these could be combined and still provide the appropriate hydraulic pressure to actuate any or all of cylinders 38 , 52 and 58 .
In an alternate embodiment, transport wheel 20 and trailer hitch 16 can be mounted on opposite ends so that transport wheels 20 are adjacent to elevation wheels 86 . The invention is not intended to be limited to the specific configuration shown in the drawings.
OPERATION OF THE INVENTION
Referring again to FIGS. 1 and 4, transport cylinder 38 is shown in an extended position such that transport wheels 20 are in their lowermost position so that road-cutting apparatus 10 may be pulled or driven along a road surface 90 with elevation wheels 86 and cutter drum assembly 74 spaced above the road surface. When apparatus 10 is at the desired location, pumps 136 , 148 and 164 are turned on. Then, transport control valve 154 is operated to actuate transport cylinder 38 to a retracted position as shown in FIG. 2 . This pulls on forward portion 36 of transport control arm 30 which rotates rear portion 28 of transport control arm 30 and wheels 20 about pivot 34 in a counterclockwise direction as seen in the drawings. As transport wheels 20 are raised, the rest of apparatus 10 is correspondingly lowered until elevation wheels 86 and measuring wheel 100 contact ground surface 90 . Further actuation of transport cylinder 38 will raise transport wheels 20 above road surface 90 as shown in FIG. 2 . Thus, apparatus 10 has a transport wheel actuation means for moving transport wheels 20 between the transport and retracted positions thereof.
The exact position of cutter drum assembly 74 with respect to road surface 90 is controlled by actuation of positioning cylinder 52 by operating positioning control valve 170 . Actuation of positioning cylinder 52 will cause positioning control arm 48 to be pivoted about lower pivot 50 . Because operating cylinder 58 and operating control arm 64 are connected to positioning control arm 48 , and because cutter frame 68 is connected to operating control arm 64 , it will be seen that actuation of positioning cylinder 52 will cause cutter drum assembly 74 to be raised and lowered with respect to road surface 90 . That is, cutter drum assembly 74 is thus pivoted about axle 88 . Preferably, cutter drum assembly 74 is positioned so that cutter elements 82 on cutter drum 80 are just above road surface 90 and not in contact therewith initially. Thus, a cutter positioning means is provided in apparatus 10 .
Cutter elements 82 on cutter drum 80 may be brought into cutting engagement with road surface 90 by actuation of operating cylinder 58 to an extended position (see FIG. 3) and disengaged by further actuation of the operating cylinder to a retracted position (see FIG. 2 ). That is, extension of operating cylinder 58 will cause operating control arm 64 to be rotated clockwise about pivot 70 which lowers cutter drum assembly 74 toward road surface 90 such that cutter elements 82 will cut a groove or impression 92 therein. See FIG. 3 . Retraction of operating cylinder 58 will rotate operating control arm 64 counterclockwise about pivot 70 , raising cutter drum assembly 74 again to the disengaged position. Referring again to FIG. 3, it will be seen that by alternately extending and retracting operating cylinder 58 as apparatus 10 is moved along road surface 90 , a series of spaced grooves 92 may be cut along the road surface leaving an uncut portion 94 between each adjacent pairs of grooves. In this way, apparatus 10 comprises a cutter operating means.
Prior to the cutting operation, first proximity switch 116 and second proximity switch 120 are positioned as desired adjacent to operating cylinder 58 and located there such as by clamping on a support member (not shown) or any other known means. The distance between proximity switches 116 and 120 will determine the total working stroke of operating cylinder 58 and thus the total movement of rod end 124 thereof.
When control circuit 108 is operational, movement of apparatus 10 along road surface 90 results in rotation of measuring wheel 100 and distance counter wheel 106 . As each cog 112 on distance counter wheel 106 move past magnetic proximity switch 110 , the magnetic proximity switch sends a signal through wires 116 to logic controller 114 . Logic controller 114 actuates operating hydraulic valve 126 which in turn actuates operating cylinder 58 . That is, logic controller 114 and hydraulic valve 126 determine when operating cylinder 58 is extended and retracted. When operating cylinder 58 is extended, rod end 124 will pass adjacent to first proximity switch 116 which sends a signal to logic controller 114 through wires 118 , stopping actuation. When operating cylinder 58 is retracted, rod end 124 thereof moves adjacent to second proximity switch 120 , and another signal is sent to logic controller 114 through wires 122 to stop actuation in that direction. Logic controller 114 includes a programmable microprocessor which can be programmed to extend operating cylinder 58 after a preselected number of “hits” sensed by magnetic proximity switch 110 as cogs 112 pass thereby and retract operating cylinder 58 after another preselected number of hits. In this way, the width of grooves 92 and the width of the uncut portions 94 therebetween may be easily and accurately determined. Further, if intermittent cutting is desired, the microprocessor in logic controller 114 may be programmed to leave a larger space between a group of grooves 92 of a preselected number. Thus, all that is necessary to vary the width of grooves 92 and the spacing 94 therebetween and any longer spacing between adjacent groups of grooves 92 is to simply reprogram the microprocessor logic controller 114 . It is not necessary to change cutters or cams or other devices as is required in some of the prior art devices.
The positioning of first proximity switch 116 and second proximity switch 120 determines the spacing above road surface 90 when in the disengaged position and the depth of grooves 92 when in the cutting or engaged position. For example, but not by way of limitation, the proximity switches could be set to position cutter drum assembly 74 one-quarter inch above road surface 90 when not cutting and set the depth of grooves 92 to one-half inch when cutting. Other dimensions could also be used as desired.
Throughout the operation of operating cylinder 58 , elevating wheels 86 stay in contact with road surface 90 allowing road-cutting apparatus 10 to be guided along the road surface. Trailer hitch 16 and elevation wheels 86 thus provide a three-point contact for apparatus 10 during operation, the hitch being the front pivoting point and the dual elevating wheels 86 providing a movable rear support. This three-point design allows full “flotation” of apparatus 10 , resulting in a highly consistent cutting action of cutter drum assembly 74 and correspondingly uniform depths, lengths and spacing of grooves 92 .
As cutter elements 82 wear, positioning cylinder 52 may be actuated by operating positioning control valve 170 to compensate so that the cutting edges of cutter elements 82 are maintained in approximately the same position with respect to road surface 90 in the disengaged position shown in FIG. 2 . This is normally done manually as necessary.
When the desired portion of road surface 90 has had grooves 92 cut therein, operating cylinder 58 is retracted to the disengaged position by operating transport control valve 154 shown in FIG. 2 . Transport cylinder 38 is re-extended to pivot transport control arm 30 about pivot 34 , thus lowering transport wheels 20 into engagement with road surface 90 so that apparatus 10 is again in the transport position shown in FIG. 1 . At this point, apparatus 10 may then be transported to another desired location with cutter drum assembly 74 and elevation wheels 86 displaced above the road surface.
It will be seen, therefore, that the road-cutting apparatus of the present invention is well adapted to carry out the ends and advantages mentioned as well as those inherent therein. While a presently preferred embodiment has been described for the purposes of this disclosure, numerous changes in the arrangement and construction of parts may be made by those skilled in the art. All such changes are encompassed within the scope and spirit of the appended claims. | A road-cutting apparatus for creating grooves or impressions in a road surface. The apparatus comprises a tool carrier with a rotatable cutter positioned adjacent thereto. A positioning control arm is hydraulically actuated to place the cutter in an operating position just above the road surface, and an operating control arm is hydraulically actuated to move the cutter into and out of cutting engagement with the road surface. The cutting is automatically carried out in response to a signal generated as a result of the distance traveled along the road surface by the apparatus. The road-cutting apparatus also comprises a transport wheel which can be placed into engagement with the road surface such that the cutter is spaced therefrom for transport of the apparatus to a desired location for cutting the grooves or impressions and raised above the road surface for the cutting operation. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority under 35 U.S.C. §119 from U.S. Ser. No. 60/053,409, filed Jul. 22, 1997.
STATEMENT AS TO FEDERALLY SPONSORED RESEARCH
This invention was made, at least in part, with funds from the Federal Government, awarded through the National Cancer Institute under contract R35-CA-56591. The government therefore has certain rights in the invention.
BACKGROUND OF THE INVENTION
This invention relates to modulating the growth of multicellular aggregates (e.g., tumors).
In tissue engineering, the successful development of a cell-based implant for restoring or improving body function through the production and/or secretion of bioactive substances is dependent upon the growth state and spatial organization of cells within the implant. For example, hepatocytes that are cultured in vitro in a three-dimensional configuration retain a more differentiated state and display more liver-specific functions than do cells grown in a two dimensional system. Similarly, the control of growth rates is of importance in biochemical engineering processes and bioreactor applications.
SUMMARY OF THE INVENTION
The invention derives from the discovery that the macroscopic growth of multicellular aggregates, such as tumors, is modulated by solid stress (i.e., pressure exerted by solids, rather than fluids). Although solid stress inhibits the growth of such aggregates on a macroscopic level, continued cell proliferation and a decrease in apoptosis results in compaction of cells within the multicellular aggregate.
The invention thus features a method for controlling the growth of a multicellular aggregate in vitro. The method entails: (i) embedding a plurality of cells in a growth matrix, (ii) measuring the level of solid stress on the cells, (iii) modulating the level of solid stress on cells within the growth matrix, and allowing the cells to grow within the growth matrix, thereby forming a multicellular aggregate, and thereby controlling the growth of the multicellular aggregate in vitro.
The invention also provides a method for producing a multicellular aggregate having a pre-selected size; the method entails: embedding a plurality of cells in a growth matrix, and allowing the cells to grow within the matrix, wherein the growth matrix exerts a degree of solid stress on the cells adequate to achieve a multicellular aggregate of the pre-selected size. In a variation of the method, one can produce a multicellular aggregate having a pre-selected size and shape. Typically, this method is carried out by embedding a plurality of cells in a growth matrix, and allowing the cells to grow within the matrix, wherein the growth matrix is contained within a vessel (e.g., a vessel that is non-uniform in shape), and the growth matrix together with the vessel exert a degree of solid stress (e.g., non-isotropic stress) on the cells adequate to achieve a multicellular aggregate of the pre-selected size and shape. These methods can be used to produce artificial tissues such as livers, skin, muscle, bone, and various other organs.
The cells may be tumor cells (e.g., from muscle, liver, colon, or mammary tumors) or non-tumor cells, such as healthy, wild-type cells. The cells can be derived from an established cell line, or they can be primary cells. Examples of preferred cell types include, without limitation, liver cells, pancreatic cells, brain cells, skin cells, muscle cells, mammary cells, and bone cells.
A variety of growth matrices having differing mechanical strengths may be used in the invention. For example, the cells can be grown in a matrix containing agarose, for example at a concentration of 0.3% to 2.0% (w/v). Alternatively, the cells may be grown in a matrix containing collagen, with or without a glycosaminoglycan such as hyaluronic acid. In another variation of this method, the growth matrix may contain alginate. In addition to containing a compound for producing a growth matrix having stiffness (e.g., agarose), the growth matrix contains nutrients for growing the cells. For convenience, conventional cell culture media can be used to dissolve the matrix-forming compound (e.g., agarose) and provide nutrients to the cells.
As shown by the examples provided below, multicellular aggregates that are grown in a non-isotropic stress field preferentially grow in the direction of the least stress. Thus, the invention also provides a method for modulating the growth pattern of a multicellular aggregate. This method entails embedding a plurality of cells in a growth matrix in which solid stress exerted by the matrix is non-isotropic and thereby defines a template which modulates the growth pattern of the multicellular aggregate. By allowing the cells to grow within the matrix, a multicellular aggregate is formed, having a shape that is dictated by the non-isotropic stress field. Such a method therefore can be used to produce multicellular aggregates of virtually any desired shape (e.g., physiologically relevant shapes, such as those of organs, or portions thereof, or shapes convenient for grafting or implantation).
In a variation of the methods described above, the invention provides a method for identifying a therapeutic compound for treating a multicellular aggregate. As described below, compounds that decrease solid stress exerted by multicellular aggregates are expected to provide a beneficial therapeutic effect by inhibiting collapse of vascular and lymphatic vessels within the multicellular aggregate, thereby facilitating blood flow and delivery of therapeutics throughout aggregates, and facilitating lymphatic drainage of tumors. This method for identifying therapeutic compounds entails:
embedding a plurality of cells in a growth matrix,
allowing the cells to grow within the growth matrix, thereby forming a multicellular aggregate,
treating the multicellular aggregate with a test compound, and
measuring a decrease in the level of solid stress on the multicellular aggregate following treatment with the test compound, relative to the level of solid stress prior to treatment, as an indication that the test compound is a therapeutic compound for treating the multicellular aggregate (i.e., as a reliever of solid stress).
In related aspect, the invention provides a method for treating a multicellular aggregate in a mammal. In this method, a mammal (e.g., a human or a rodent, such as a mouse, in an animal model of a human disorder) is identified as being afflicted with a multicellular aggregate (e.g., a tumor), and solid stress exerted by the aggregate is relieved. Relief of solid stress can be accomplished, for example, by administering to the mammal an antibody that specifically binds an integrin, or an enzyme that dissolves the extracellular matrix (e.g., a collagenase, hyaluronidase, or protease). Alternatively, the extracellular matrix can be dissolved (and solid stress relieved) by topical treatment of the extracellular matrix with heat, ultrasound, microwaves, radiation, or the like.
By “solid stress” is meant pressure exerted on a solid by another solid, for example stress exerted on a multicellular aggregate by a growth matrix. Solid stress, therefore, is distinct from interstitial fluid pressure.
By “multicellular aggregate” is meant a plurality of connected cells (e.g., as in a mass of tissue). The cells of such an aggregate may be tumorigenic or non-tumorigenic. They need not be, but can be, homogenous. Included are primary cells, as well as cells of established cell lines. If desired, the cells may be wild-type, mutated (naturally or intentionally), or genetically engineered to produce a recombinant gene product (e.g., a secreted protein).
The invention offers several advantages. The level of solid stress imposed on cells can readily be modulated by embedding and growing the cells in a growth matrix of a defined stiffness (i.e., gel strength). By controlling stress exerted on the multicellular aggregate, one can control the proliferation and apoptotic rates of cells (e.g., tumor cells) within the aggregate. By applying stress in a non-isotropic manner on the growing multicellular aggregate, one can shape the multicellular aggregate into nearly any shape. Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of an exemplary apparatus for growing multicellular aggregates in a growth matrix such as an agarose gel.
FIG. 2A is a graph depicting the growth kinetics of LS174T spheroids in free suspension and in 0.3, 0.5, 0.7, 0.8, 0.9 and 1.0% agarose gels. The mean diameter ± the standard error (SE) of the spheroid population is shown for 5 separate experiments (with 50 to 80 spheroids at each time point for each culture condition).
FIG. 2B is a graph depicting the growth kinetics before and after (arrow) release of spheroids from the gel (from 0.5, 0.7 and 1.0% agarose). The mean diameter ± SE of the spheroid population is shown; the results are representative of 5 separate experiments.
FIGS. 3A-3C are graphs depicting the growth of LS174T in free suspension and gels confined in 1.0-mm ID glass capillary tubes (orthotopic stress experiments). The longitudinal (b) versus radial dimensions (a) of tumor aggregates are shown for spheroids in free suspension after 25-day culture in glass tubes (FIG. 3A, fit: y=0.99x+0.70, r 2 =0.99); in 0.7% gels after 25 days (FIG. 3B, fit: y=2.23x−43.5, r 2 =0.86) ; or in 0.7% gels, 15 days after releasing the gels from the tubes (FIG. 3C, fit: y=1.05x+55.3, r 2 =0.88). Dotted lines indicate y=x axis. Results are representative of three separate experiments, with 6 tubes per experiment for each condition.
FIGS. 4A-E are histograms depicting the cellular characteristics of 28-day-old spheroids. FIGS. 4A and 4D depict cell proliferation, with dependence on spheroid diameter depicted in FIG. 4 D. The range was 180-520 μm for 0.7% gel spheroids. The size distributions of the two samples were comparable. FIGS. 4B and 4E depict cell apoptosis, with FIG. 4E depicting dependence on spheroid diameter. The range was 180-520 μm for free suspension spheroids, 240-440 μm for 0.7% gel spheroids (comparable size distributions). FIG. 4C depicts cell density. The mean ± SE of the spheroid population is shown. Bold bars in FIGS. 4D and 4E schematically depict proliferation and apoptotic rates.
DETAILED DESCRIPTION
The invention derives from the discovery that solid stress exerted on a multicellular aggregate alters the growth pattern of the multicellular aggregate. More specifically, solid stress inhibits growth of the aggregate on a macroscopic level and decreases the apoptotic rate of cells within the aggregate, without affecting the cell proliferation rate. Consequently, solid stress causes compaction of cells within the aggregate. Thus, the invention provides in vitro methods for modulating the growth of multicellular aggregates which entail measuring the solid stress exerted by the multicellular aggregate (e.g., for identifying compounds that may relieve solid stress imposed upon vessels within tumors and enhance delivery of therapeutics to the aggregate).
As exemplified by the working examples that follow, the invention provides a method for controlling the growth of a multicellular aggregate in vitro. In this method, cells are embedded in a growth matrix, and allowed to grow within the matrix and thereby form a multicellular aggregate. Growth of the multicellular aggregate within the growth matrix is controlled by measuring and modulating the level of solid stress on the aggregate within the matrix.
The multicellular aggregate can be formed from any of a variety of cell types, with mammalian cells being preferred. Such cells can be primary cells, or they can be obtained from an established cell line. Numerous cell types are publicly available from sources such as the American Type Culture Collection, for example. In practicing the invention in vitro, cells typically are embedded in the growth matrix at a concentration of about 1,000 to 5,000 cells/ml, and allowed to form multicellular aggregates by maintaining the cells within the matrix for about 10 to 100 days (typically, 20-60 or 20-40 days). Conventional cell culture media can be used to provide nutrients to the cells, and the cell culture media typically is replaced daily.
A variety of growth matrices are suitable for use in the invention. Growth matrices such as agarose, alginate, collagen, and collagen supplemented with glycosaminoglycans, can readily be prepared by one of ordinary skill in the art. Typically, such growth matrices are prepared by dissolving the matrix-forming compound (e.g., agarose) in a conventional cell-culture medium known to be suitable for growing the cells of choice (e.g., Dulbecco's Modified Eagle's Medium). Agarose generally will be used at a concentration of 0.3 to 2.0% (w/v); concentrations of about 0.9% agarose or higher substantially inhibit growth of the multicellular aggregate. Alginate generally is used at a concentration of about 0.5% to 35% (typically, 0.5% to 4%), and collagen typically is used at a concentration of about 0.05% to 0.3% (e.g., 0.1% to 0.3%). If desired, collagen growth matrices can be supplemented with glycosaminoglycans (e.g., hyaluronic acid) typically at a concentration of about 0.1 μg/ml to 10 μg/ml.
When multicellular aggregates grow in in vitro growth matrices, such as agarose gels, stress gradually accumulates around the aggregate due to the progressive displacement of the matrix by the growing cellular mass. The pressure exerted by the stress field can be calculated based on the size of the growing aggregates and the mechanical properties of the growth matrix. A detailed description of an exemplary method for determining the level of stress exerted is provided below. Other methods for measuring solid stress also may be used. For example, the stress can be measured directly using optical methods, such as polarized light microscopy to assess the strain placed upon the growth matrix surrounding the multicellular aggregates.
By measuring and modulating the level of solid stress initially placed on cells that form a multicellular aggregate, one can control the growth of the aggregate within a growth matrix. The initial levels of solid stress can be increased by increasing the stiffness of the growth matrix (e.g., concentration of agarose). As described below, increasing the initial level of solid stress in a growth matrix inhibits the macroscopic growth of the multicellular aggregate and decreases the apoptotic rate of the cells within the aggregate, without affecting the proliferation rate. Thus, increasing the initial solid stress on the aggregate leads to compaction of cells within the aggregate.
The effects of solid stress on the growth patterns of multicellular aggregates can be reversed by alleviating the solid stress. For example, in vitro, aggregates can be released from growth matrices by dissolving the growth matrix. Agarose, for example, can be dissolved by treating the agarose gel with agarase at a concentration of 1 to 10 U/ml (typically, 5 U/ml) until the gel is dissolved (e.g., for 2 days). Growth matrices that contain collagen can be dissolved by treating the matrix with collagenase at a concentration of about 1 to 5% in PBS (e.g., 3%). Growth matrices containing alginate can be dissolved by changing the ionic strength of the matrix, e.g., by infusing manganese into the matrix. Once the extracellular matrix is dissolved, the released multicellular aggregates can be grown in culture medium as free suspensions.
In an in vivo setting (e.g., in a mammal afflicted with a tumor or a benign multicellular aggregate), solid stress exerted by the multicellular aggregate is sufficient to cause the collapse of blood and lymphatic vessels. The solid-stress-induced pressure on blood vessels, resulting in collapse of vessels, can inhibit delivery of therapeutic agents throughout the multicellular aggregate. Similarly, solid-stress-induced pressure on lymphatic vessels can impair lymphatic draining in cancer patients. Thus, compounds and methods for relieving solid stress are useful in therapeutic regimens for treating patients afflicted with tumors.
In vivo, solid stress imposed by multicellular aggregates (e.g., tumors) can be relieved by modulating the mechanical properties of the interstitial environment. For example, solid stress can be relieved by treating the mammal with an anti-integrin antibody, such as antibodies that specifically bind α and β integrins. Such antibodies can be obtained commercially or produced according to art-known immunization methods. Solid stress also can be relieved by treating the mammal with collagenase and/or hyaluronidase to dissolve collagen and/or hyaluronic acid in the extracellular matrix surrounding the multicellular aggregate. Alternatively, proteases, such as metalloproteases, can be used to break up the extracellular matrix and relieve solid stress imposed on the multicellular aggregate.
Although such antibodies and enzymes can be delivered to the multicellular aggregate by systemic administration to the mammal systemically, these therapeutics typically will be administered topically or regionally to an area containing the multicellular aggregate. Generally, antibodies are administered at a dosage of 5 to 30 mg/kg of body weight, while enzymes are administered at a dosage of 1 to 10 mg/kg body weight. As an alternative to using antibodies or enzymes to alter the interstitial environment, non-biological means can be used. For example, solid stress can be relieved by dissolving the extracellular matrix surrounding the aggregate with heat, microwave radiation, ultrasound, and the like.
The in vitro methods described above can readily be adapted for identifying new compounds that relieve solid stress. In an exemplary method, cells (e.g., tumor cells) are embedded in a growth matrix, such as 0.3 to 1.0% agarose. The cells are allowed to grow until the resulting multicellular aggregates reach plateau phase (i.e., their final size), at which point the multicellular aggregate is treated with a test compound. Solid stress exerted by the multicellular aggregate is determined both before and after treatment with the test compound, and a decrease in the stress levels indicates that the compound is useful for treating the multicellular aggregate. Virtually any compound (e.g., polypeptides or small organic molecules) can be used as the test compound, provided it can diffuse through the growth matrix. In an alternative method, the cells are treated with the test compound prior to reaching plateau phase, or even before embedding the cells in the growth matrix.
Because growing multicellular aggregates are responsive to solid stress imposed by the growth matrix, the growth pattern of a multicellular aggregate can be modulated by growing the aggregate in a non-isotropic stress field. The multicellular aggregate preferentially grows in the direction of the least stress. In a growth matrix in which the stress field is essentially uniform, cells grow into spheroid multicellular aggregates. The stress field can be made non-isotropic (e.g., orthotropic) by containing the growth matrix within a rigid container, such as a glass tube, a cylindrical hollow fiber having porous walls for nutrient access, or a container of another desired shape. Solid stress exerted by the growth matrix, rather than the rigid container itself, constrains growth of the multicellular aggregate. By growing the cells in a growth matrix in a confined configuration and having a non-isotropic stress field, the non-isotropic stress field defines a template for growth of multicellular aggregate. As shown by the example provided below, the non-isotropic stress field exerted on the aggregate can be used to modulate the growth pattern of the aggregate and affect the final shape of the aggregate (e.g., to produce an ellipsoid, rather than spheroid, aggregate). By modulating the growth pattern of the multicellular aggregates, one can produce aggregates in a variety of physiologically relevant shapes (e.g., liver-shaped or pancreas-shaped aggregates as models of liver or pancreas). These shaped multicellular aggregates have many applications in tissue engineering, e.g., as implants or bioreactors.
EXAMPLES
Before describing the results of several working examples, various parameters of the methods employed, and of the invention in general, are described in detail. These examples are provided to illustrate, not limit, the invention, the metes and bounds of which are defined by the following claims.
METHODS
Culture of tumor spheroids in free suspension and agarose gels. The growth kinetics of three tumor cell lines were studied. Human colon adenocarcinoma cells (LS174T) were obtained from the American Type Culture Collection (ATCC; Rockville, Md.). Murine mammary carcinoma cells (MCaIV) were isolated from a spontaneous tumor (Department of Radiation Oncology, Massachusetts General Hospital, Boston, Mass.); other suitable murine mammary carcinoma cells are available from the ATCC. BA-HAN-1 rat rhabdomyosarcoma cells (clones A, B, C; from least to most differentiated) were provided by Drs. C.-D. Gerharz and H. Gabbert (Institute of Pathology, University of Dusseldorf, Germany). Other suitable rhabdomyosarcoma cells can be obtained from the ATCC or from commercial suppliers.
Cells were cultured in Dulbecco's Modified Eagle's Medium containing 3.7 g/l NaHCO 3 , 10% fetal calf serum, 1% glutamine, and glucose (at 1.0 g/l for LS174T and MCaIV, and at 4.5 g/l for BA-HAN-1). Tumor cells were grown as multicellular spheroids in free suspension or in agarose gels of varying agarose concentrations (0.3% to 2.0%). The cells were grown in agarose gels in “well inserts” that were suspended between upper and lower compartments containing medium. Gels seeded with single-cell suspensions were prepared in 1-inch (outer diameter), sterile well inserts (Collaborative Biomedical Products, Bedford, Mass.) with porous, 1 μm filter membranes. This configuration resulted in two separate medium compartments, an upper one and a lower one (see FIG. 1 ).
Agarose (type VII, low gelling temperature) was obtained from Sigma (St. Louis, Mo.), and stock solutions of 2.0% (w/v) agarose dissolved in double-distilled water were prepared. Final agarose concentrations (ranging from 0.3% to 2.0%) were obtained by adding the appropriate amounts of double-strength medium (Gibco/BRL) and cell culture medium (described above) to the 2.0% agarose stock solution (Iscove et al., Academic Press, 1979, in Immunological Methods, pgs. 379-385). The bottom of each well insert was first coated with a supportive layer of 1% agarose (in a volume of approximately 0.5 ml), which was allowed to gel at room temperature for 10 minutes. The next layer of agarose was formed by adding a 2-ml liquid solution of agarose (at the appropriate concentration, as described above) inoculated with single tumor cells at a controlled cell seeding density. The pH of the liquid agarose was 7.3±0.1. During the inoculation process, the cell suspension was added at a time when the agarose solution was still liquid (>37° C.), yet cool enough to prevent cell damage (<40° C.). The cell-containing agarose medium was then allowed to gel at room temperature for 20 minutes. Finally, 3 ml of culture medium were added to the upper and lower compartments. The medium in each compartment was changed daily, and the spheroid cultures remained viable for at least 60 days.
Spheroids of cells grown in free suspension served as controls. The plastic surface of the lower compartment was first coated with a thin film of 1.0% agarose to prevent cell attachment. A single-cell suspension mixed with 3 ml culture medium was then introduced into the lower compartment. The initial cell seeding density matched the one used for the cultures grown in agarose gels. For the controls, the well insert was filled with a cell-free 1.0% agarose gel. Culture medium (3 ml) was then added to the upper compartment. The culture medium in the upper compartment, but not the lower compartment, was changed daily. With this configuration, the nutrients for feeding the cells must travel through the cell-free agarose gel before reaching the cells in the bottom compartment. Thus, the free suspension spheroids faced a less favorable nutrient environment that did the cells embedded in agarose.
In selected experiments, tumor spheroids grown in agarose gels were released from the gel by enzymatic digestion of the agarose gel with 5 U/ml agarase (Sigma). The conditioned culture medium was collected from the lower and upper compartments prior to treatment of the gel with agarase, and the released spheroids were cultured in the conditioned medium for 72 hours. Subsequent culturing in free suspension was carried out as described above. As controls, free cell suspension controls were also treated with 5 U/ml agarase, to confirm that the agarase used to dissolve the agarose gels had no significant effect on spheroid growth.
To investigate the effect of a non-isotropic stress field on tumor growth, cells were grown in 0.7% and 1.0% agarose gels embedded in glass capillary tubes (1-mm ID, 1-cm length, Vitro Dynamics, Rockaway, N.J.). Free suspension controls were grown in the central section (0.4 cm length) of capillary tubes, the extremities of which (0.3 cm on each side) were filled with cell-free, 1.0% agarose. All tubes were floated in a Petri dish containing 10 ml culture medium. The initial cell seeding density for the controls was the same as the density used for the isotropic stress experiments. After 25 days, the cell-containing gels were expelled from the glass tubes by pressure and resuspended in culture medium. Growth was monitored for 15 additional days.
Spheroid volumetric growth was assessed every 2 to 4 days (for up to 60 days) by measuring spheroid diameter using high-resolution videomicroscopy. At least 50 spheroids were measured at each time point in each well. Only spheroids that were more than two spheroid diameters apart from each other were considered to ensure that their stress fields did not overlap. Clonal efficiency was measured and defined as the ratio (expressed in %) of the number of spheroids (aggregates with >10 cells) present in the well at time t divided by the number of cells seeded at time t=0.
Mechanical properties of agarose gels and stress field computation. The growth process of tumor spheroids in agarose gels is characterized by an equilibrium between the thrust of growing tumor cells and the elastic constraint of the agarose chains. To be able to divide, cells (spheroids) must stretch the polymer network (i.e., matrix) surrounding the cells; cells cannot digest the matrix or migrate through it. The network, in turn, exerts an elastic stress on the spheroid surface. As growth proceeds, an elastic stress field builds around the spheroid, the magnitude of which depends on the mechanical properties of the agarose gel. In addition, during growth, fluid will be squeezed out from the gel regions proximal to the spheroid surface, leading to compaction of the gel around the spheroids. Therefore, to calculate the stress around a spheroid growing in a gel, one defines a constitutive equation of the gel, which relates the strain to the stress, and determines the mechanical parameters with appropriately designed experiments. The agarose gel is assumed to be a poroelastic material, i.e., a hyperplastic polymer network filled with a fluid. Thus, the gel can be described with an exponential-hyperbolic strain energy function with four constitutive parameters ( W = C ( β ( I - 3 ) - I ) + γ ( III - 1 ) ( III - φ 0 ) n )
where I and III are the first and third strain invariants, and C, β, γ and n are empirical parameters. The chosen strain energy function adequately described the traction and compression states of agarose gels, as determined in confined and unconfined compression tests. In these tests, a fixed quantity of agarose was cast in a stainless steel container of 38 mm diameter and gelled at 4° C. for 1 hour. The system was then transferred to a dynamometer (Inston Machine Mod. 4204) to determine the constitutive relation between stretch and applied load. For confined compression tests, the agarose sample was kept in the metallic mold to prevent radial displacement. The sample was compressed by the upper surface with a porous stainless steel disc (37.5 mm in diameter) directly connected to the load cell. For unconfined compression test, the agarose sample was removed from the metallic mold and compressed by a non-porous disc. A cross-head speed of 0.06 mm/min was used to obtain quasi-static tests. All tests were performed at a controlled temperature of 37° C. The mechanical parameters (C, β, γ and n) of agarose gels at 0.5, 0.7, 0.8, 0.9 and 1% were then obtained by fitting the experimental data. The stress field around the spheroid was calculated by integrating the equilibrium equations, assuming that the spheroids were not interacting mechanically, i.e., the stress field around a given spheroid did not overlap with that of a neighboring spheroid. The local gel concentration around the growing spheroid also was calculated.
Proliferation and apoptosis assays. A monoclonal antibody specific the proliferating cell nuclear antigen (PCNA), TDT-mediated dUTP-biotin nick end-labeling (TUNEL), and propidium iodide assays (PI) were used to quantify proliferating cells, apoptotic cells, and total cell number, respectively, in frozen sections of tumor spheroids. Spheroids were isolated manually, directly (from free suspensions) or after partial digestion (using 5 U/ml agarase) of the agarose gel. The spheroids then were frozen in OCT medium in a dry ice/methanol bath. Using a cryostat, thin sections (8 to 10 μm) of the spheroids were cut. The thin sections, on slides, were fixed for 30 minutes in 0.2% paraformaldehyde, followed by 10 minutes in 100% ethanol, then rinsed three times in phosphate-buffered saline (PBS). Slides were then used either for the PCNA or the TUNEL assay. PCNA sections were incubated for 60 minutes with monoclonal mouse anti-PCNA (DAKO, Santa Barbara, Calif.; diluted 1:50 in PBS containing 0.5% BSA), then for 30 minutes with streptavidin-conjugated FITC (BioSource International, Camarillo, Calif.; 1:50 in PBS containing 0.5% BSA). Each step was followed by a three-step wash in PBS. Apoptosis was measured using the MEBSTAIN apoptosis kit, which employs the TUNEL assay (#8440, MBL, Nagoya, Japan). To determine the total cell number, all slides were incubated for 30 minutes with 1 mg/ml PI (Sigma), rinsed three times in PBS, and mounted in PBS-glycerol. Sections ere imaged using an epi-fluorescence microscope (Zeiss Axioplan, Oberkochen, Germany) and high-resolution digital imaging. The percentage of proliferating cells was obtained by dividing the number of PCNA-positive cells by the total number of cells (PI-stained cells). A similar procedure was used to determine the percentage of apoptotic cells.
The results of several experiments, carried out as examples, now follow.
Example I
Solid Stress Inhibits Tumor Spheroid Growth
This example demonstrates that the growth kinetics of multicellular aggregates are modulated by solid stress. The initial stiffness of the growth matrix accelerates the response to growth-induced stress. To demonstrate the effects of solid stress on growth, tumor spheroids were cultured in gels of increasing agarose concentrations (as described above), thereby increasing the initial stiffness of the growth matrix in which the cells were embedded. As described below, solid stress inhibited tumor growth of cells from each of the species tested (human, mouse, and rat), tissues of tumor origin (colon, mammary, and muscle), and differentiation state (claims A, B, and C, of the BA-HAN-1 cell line). While the examples set forth below utilized agarose gels, similar results were obtained when a collagen gel was used (at 2.5 mg/ml).
Human Colon Adenocarcinomas: For spheroids of human colon adenocarcinoma cells (LS174T cells), similar growth rates and final spheroid sizes were obtained at gel concentrations of 0.3, 0.5, 0.7, and 0.8% agarose. The mean diameter ± the standard error (SE) was 363±37.2 to 450±37.9 μm. The diameters obtained by growing the cells in spheroids were significantly lower than the diameters obtained by growing cells as free suspensions (897±40.0 μm, p<0.001), indicating the low levels of agarose in the growth matrix significantly inhibit cell growth. At higher agarose concentrations of 0.9% and 1.0%, growth of the tumor spheroids was further inhibited, with mean diameters of 200±37.7 and 85±9.3 μm, respectively (FIGS. 2 A- 2 B). These data indicate that a threshold for significant growth inhibition is reached at an agarose concentration of 0.9% to 1.0% (FIGS. 2 A- 2 B).
Although the growth kinetics varied among the culture conditions, the clonal efficiencies (i.e., a measure of spheroid formation, as described above) were similar (>90%) at all of the culture conditions (i.e., for free cell suspensions or at agarose concentrations ranging from 0.3% to 1.0%). Clonal efficiencies were significantly reduced only at higher agarose concentrations. For example, at 1.4% agarose, the clonal efficiency was reduced to 12%, and at 1.8% agarose, the clonal efficiency was reduced to 5%.
Rat Rhabdomyosarcomas: While the results described above were obtained with human colon adenocarcinoma cells, similar results also were obtained with three rat rhabdomyosarcoma clones. Three BA-HAN-1 rat rhabdomyosarcoma clones, at varying states of differentiation, were used. The resulting spheroids of the three clones displayed similar growth rates and final sizes when cultured in 0.7, 0.8, 0.9, and 1.0% gels. The spheroid diameters ranged from 218±16.6 to 273±18.3 μm, which was significantly smaller than the diameters produced with the same cells in free suspension (1050±87.0 μm; p<0.002). For all of the culture conditions, the clonal efficiency was greater than 90%. At a higher agarose concentration (1.4%), rhabdomyosarcoma spheroid growth was further reduced (102±10.7 μm) and the clonal efficiency was decreased to 20%. Thus, solid stress inhibits growth of rhabdomyosarcoma spheroids.
Murine mammary carcinomas: An inhibition of tumor growth also was observed with MCaIV murine mammary carcinoma spheroids. At agarose gel concentrations of 0.3, 0.5, and 0.7%, the mean diameter of the murine mammary tumor spheroids ranged from 135±1.40 to 141±19.8 μm. At a higher agarose concentration (1.0%), tumor growth was significantly inhibited; the mean diameter was 55±10; p<0.002. At all of the agarose concentrations (0.3 to 1.0%), the clonal efficiency was greater than 87%.
Threshold Levels of Solid Stress: As shown herein, the growth of tumor spheroids in gels is responsive to a threshold level of stress, with the stress accumulating locally due to a gradual displacement of the gel by the growing spheroids. Although the final size of spheroids is dependent upon the initial stiffness of the growth matrix (e.g., agarose concentration), solid stress accumulates around spheroids to a threshold level that is comparable for all spheroids which have reached their final size (i.e., plateau phase), regardless of initial stiffness of the growth matrix. In other words, the multicellular aggregates grow in the growth matrix until a threshold (i.e., growth-inhibitory) level of solid stress is reached. As shown in Table 1, the cells in the multicellular aggregates reach a threshold level of solid stress of approximately 45 to 120 mm Hg. The calculations of accumulated stress also showed that the stress field surrounding a plateau-phase spheroid drops to its initial, pre-growth value within a distance of one spheroid radius. In other words, the calculations of stress fields in the gel are not due to spheroids within the gel exerting stress on each other, since spheroids that were closer than one diameter apart ere excluded from the calculations.
TABLE 1
Solid stress calculations around spheroids cultured in gels of varying
initial concentrations of agarose. Spheroid size refers to the average size
of the population of spheroids. The interfacial gel concentration is the
effective gel concentration faced by an average-sized
spheroid in its growth plateau phase.
Initial
Final
spheroid
spheroid
Final Stress
Gel
size
size [μm]
around spheroid
concentration
[μm]
(from FIG. 2A)
[mm Hg]
0.5%
20
414
45
0.7%
24
370
105
0.8%
24
360
100
0.9%
23
200
120
1.0%
24
85
50
Example II
Tumor Spheroid Growth Resumes Following Stress Alleviation
To provide further evidence that solid stress modulates growth of multicellular aggregates, stress was alleviated, and the effects of stress alleviation were ascertained. In this experiment, human colon adenocarcinoma cells (LS174T cells) were grown to plateau phase spheroids in agarose gels. To alleviate the stress placed on the spheroids, the agarose gels were enzymatically digested with agarase, as described above. The released tumor spheroids then were placed in an equivalent volume of “used” cell culture medium for an additional 72 hours and grown as free suspensions. As shown in FIG. 2B, the spheroids resumed growth within 2 to 4 days. The growth rates of spheroids released from agarose gels were comparable to those obtained for control cells in free suspension. The diameters of the released spheroids increased until they eventually were comparable to those obtained for spheroids that had been grown as free suspensions. Similar results were obtained or BA-HAN-1 rat rhabdomyosarcoma spheroids released from gels. Thus, this example shows that the inhibitory effect of stress on growth is reversible, and relaxation of stress allows growth-inhibited spheroids to resume normal growth kinetics.
Example III
Use of Non-uniform Stress to Modulate the Shape of Growing Multicellular Aggregates
This example demonstrates that the shape of a growing multicellular aggregate can be controlled by modulating the stress field in which the aggregate grows. More specifically, multicellular aggregates preferentially grow in the direction of least stress. In this example, LS174T cells were grown in cylindrical glass capillary tubes with an inner diameter comparable to the final size of free suspension spheroids (1 mm). With this configuration, radial stress on the growing spheroid increases faster than does axial stress, thereby resulting in a non-isotropic stress field.
The growth patterns of cells in this confined geometry and in free suspension were compared with cells in this confined geometry and in 0.7% agarose gels (FIGS. 3 A- 3 C). To characterize the shapes of the resulting multicellular aggregates, the following calculations were used. For each culture condition, the dimension of the aggregate along the tubes's longitudinal axis (b) versus the dimension along the tubes's radial axis (a) was plotted, as shown in FIGS. 3A-3C. At 25 days after seeding the cells in the tubes, cells in free suspension grew to nearly perfect spheroids, as indicated by a slope (b/a) of 0.99 (FIG. 3A; r 2 =0.99). By contrast, the multicellular aggregates in the 0.7% agarose gels grew to ellipsoid shapes, with the longer axis parallel to the longitudinal axis of the capillary tube. This difference in the shape of cells grown in agarose can be appreciated quantitatively, as the slope (b/a) for these cells was 2.23 (FIG. 3B; r 2 =0.86). To confirm that the differences in shape were due to the solid stress exerted upon the multicellular aggregates, the tumor aggregates were released by treating the gels with agarase (as described above). Upon release, the aggregates continued to grow into nearly spheroid shapes; at 15 days after release, the aggregates had a slope (b/a) of 1.05 (FIG. 3C; r 2 =0.88). Similar results also were obtained after growing cells in 1.0% agarose gels. Thus, this example demonstrates that the growth pattern of multicellular aggregates can be modulated by growing cells in a non-isotropic stress field, with the cell aggregates preferentially growing in the direction of the least stress.
Example IV
Solid Stress Inhibits Cell Growth Without Inhibiting Cell Proliferation Rates
The stress-dependent control of tumor growth, seen at the macroscopic level, is sensed at the microscopic levels by stress-induced changes in cellular growth patterns. While the size of a multicellular aggregate is influenced by solid stress, the proliferation rate of cells within the aggregate is not affected by solid stress. Thus, the solid stress exerted upon a multicellular aggregate results in compaction of cells within the aggregate. Two approaches were taken to elucidate the effects of solid stress on cell proliferation rates:
The growth kinetics of spheroids generally follow Gompertz law, an empirical relationship for volume growth ln ( ln V V 0 ) = - α t + V max V 0
where V is a measure of spheroid size, V 0 is the initial size, and V max is the final spheroid size. Parameter a is the proliferation rate of cells in the proliferative pool when one uses a simple, two-compartment model (proliferating vs. non-proliferating cells). In the first approach, the growth curves for the spheroids, as shown in FIGS. 1A-1B, were re-plotted as ln (ln (V/V 0 )) vs. time t. The data were best approximated by single linear fits (r 2 ≧0.93), yielding values of parameter α, which is the cell proliferation rate. For LS174T spheroids, values of a were nearly identical for cells grown as free suspensions, or in 0.3-1.0% agarose gels. The value of α (i.e., the proliferation rate) did not change significantly after releasing the spheroids from the gels, even though an increase in tumor growth is seen on a macroscopic level after releasing spheroids from agarose gels (as described above). Similar results were obtained with spheroids formed by BA-HAN-1 rat rhabdomyosarcoma cells and MCaIV murine mammary tumor cells. This example thus indicates that, although solid stress inhibits the growth of the multicellular aggregates on the macroscopic level, the proliferation rate is not affected by solid stress.
In a second approach, PCNA and TUNEL assays were used to quantify cell proliferation and apoptosis, respectively, in plateau-phase spheroids of LS174T cells. The cells were cultured either as free suspensions or in 0.7% or 1.0% agarose gels. With increasing gel concentrations (i.e., with increasing levels of solid stress), the percentage of proliferating and apoptopic cells decreased, and cellular density increased (FIGS. 4 A- 4 C). Positive PCNA staining was limited to the outermost layers of cells in the multicellular aggregates, while apoptosis was detected exclusively in the central parts. The inner regions of spheroids grown as free suspensions contained large voids that were attributed to necrosis. Few of these types of voids were seen in spheroids grown in gels.
In analyzing the PCNA and TUNEL data, the data were divided into two categories, based on the size of the spheroid: small spheroids (having a diameter <300 μm) versus large spheroids (having a diameter >300 μm). For cells grown as free suspensions or in 0.7% gels, there was no significant correlation between the size of the spheroid and the number of proliferating cells measured with PCNA, as shown in FIG. 4D (linear curve fit: r 2 =0.02 and 0.05, respectively). Thus, the proliferation rate is not significantly affected by solid stress.
Although solid stress does not significantly affect cell proliferation rates, stress decreases the apoptotic rate. In spheroids in free suspensions, the percentage of apoptotic cells increased with an increase in spheroid size (FIG. 4E; r 2 =0.72). In contrast, the percentage of apoptotic cells was not increased with size in cells grown in 0.7% agarose (FIGS. 4 D- 4 E).
The data presented in this example show that, while accumulation of solid stress does not significantly affect the proliferation rate of cells in multicellular aggregates, accumulation of solid stress decreases the apoptotic rate of cells in multicellular aggregates. Consequently, one can infer that the growth of multicellular aggregates under solid stress is accompanied by compaction of cells within he aggregate.
Therapeutic Applications
The experiments summarized above demonstrate that multicellular aggregates grow, macroscopically, until a threshold level of solid stress (approximately 45-120 mm Hg) is accumulated at the surface of the spheroid. Additional cell proliferation results in compaction of the cells within the multicellular aggregate. Consequently, such multicellular aggregates can exert as much as 45-120 mm Hg of solid stress in vivo. This amount of pressure is sufficient to induce a local collapse of blood vessels within tumors or other multicellular aggregates in vivo, since tumor microvascular pressures average only 6-17 mm Hg. Thus, solid pressure exerted by growing tumors is sufficient to restrict blood flow throughout tumors. Similarly, the high levels of pressure generated by tumor growth, as shown by the above experiments, are sufficient to induce the collapse of lymphatic vessels. Accordingly, the relief of solid stress within tumors or other multicellular aggregates can now be expected to increase blood flow and lymphatic drainage in such multicellular aggregates. In addition, the above examples show that increased levels of solid stress inhibit the rate at which cells in the multicellular aggregate undergo apoptosis. Thus, relief of solid stress in multicellular aggregates, such as tumors, now can be expected to increase the rate of apoptosis and thereby facilitate elimination of tumor cells or other undesirable cells of multicellular aggregates. Alleviation of solid stress can be accomplished by any of several suitable methods, as described above. | Cells in a matrix or in the matrix in a vessel are grown to form a multicellular aggregate. Pressure is exerted on the growing cells by the matrix or the matrix together with the vessel due to growing cellular mass displacing the matrix. A value representing pressure exerted on the cells is calculated and the pressure is modulated to control growth of the multicellular aggregate, or to produce a multicellular aggregate of a pre-selected size or a pre-selected size and shape. Matrices include agarose, alginate and collagen gels, and the pressure exerted on the cells can be non-isotropic. The cells may be tumor cells, or liver, pancreatic, brain, skin, bone or muscle cells, and cell growth can be in vitro or in vivo. When collagen forms the matrix, the matrix may contain glycosaminoglycan. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2002-200103, filed on Jul. 9, 2002, the entire contents thereof being incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a chemically amplified resist material and a patterning method that uses the same. More particularly, the present invention relates to a chemically amplified resist material useful for forming patterns for microfabrication in the production of semiconductor devices and magnetic heads, and a patterning method that uses the chemically amplified resist material.
2. Description of the Related Art
In recent years, chemically amplified resists containing photo acid generators have been widely used for microfabrication of semiconductor devices (see, for example, J. M. J. Frechet, et al., Proc. Microcircuit Eng., 260 (1982); H. Ito, et al., “Polymers in Electronics”, ACS Symposium Series 242, T. Davidson., ed., ACS, 11 (1984); and, U.S. Pat. No. 4,491,628 (1985)). Chemically amplified resists generate acids from photo acid generators by being irradiated with ultraviolet rays, electron beam, X-rays or convergent ion beam, and this acid functions as a catalyst during post exposure bake, with the resulting catalytic reaction changing the exposed portion into alkaline-soluble (in the case of a positive resist) or alkaline-insoluble (in the case of a negative resist). Consequently, the use of a chemically amplified resist makes it possible to improve exposure sensitivity.
As chemically amplified resists use a catalytic reaction driven by an extremely small amount of acid, they are susceptible to the effects of external impurities. If the impurities are basic species in particular, they are known to cause deactivation of the acid that leads to deterioration of the form of the pattern formed by exposure and development. Those locations at which deterioration of the pattern form occurs are in close proximity to the interface between the upper and lower portions of the formed pattern (surface layer and bottom of the resist film), and this deterioration is mainly caused by basic species present in the atmosphere and on the substrate surface, respectively.
With respect to the effect of basic species present in the atmosphere, since basic species adsorbed onto the surface layer of the resist film and basic species diffused in the resist film from the surface layer neutralize an acid generated from the photo acid generator by exposure, solubilization (in the case of a positive resist) or insolubilization (in the case of a negative resist) of the resist material near the surface layer of the resist film of the exposed portion is impaired. As a result, the pattern of a positive resist takes on the shape of a T-top (formation of a poorly dissolving surface layer), while the pattern of a negative resist takes on the shape of a round top (missing upper portion of the pattern).
On the other hand, with respect to the effects of basic species from the substrate, since basic species present on the substrate surface and basic species diffused in the resist from the substrate surface neutralize the acid generated by exposure, solubilization (in the case of a positive resist) or insolubilization (in the case of a negative resist) of the resist material near the interface with the substrate is impaired. As a result, the pattern of a positive resist takes on the form of a footing, while the pattern of a negative resist takes on the form of an undercut. The effects of basic species from the undercoating in this manner are even more remarkable in cases in which a film containing basic species such as SiN, SiON, TiN, BPSG, BSG or PSG is formed on the substrate surface. In addition, footings and undercuts similarly occur due to diffusion of acid generated in the resist into an underlying film.
The occurrence of pattern defects such as the T-top, round top, footing or undercut as described above prevents the underlying film from being processed to the predetermined dimensions, thereby making microfabrication of semiconductor devices difficult.
Although the effects of basic species in the atmosphere can be suppressed to a certain extent by controlling the process atmosphere by, for example, using a basic species adsorbing filter, this results in the problem of excessive complexity of the production equipment.
On the other hand, the formation of a protective film comprised of a thermosetting resin and so forth between the substrate and resist film had been proposed as a method for avoiding the effects of basic species from the substrate. However, the protective film must be coated to an adequate thickness by a method such as spin coating or CVD and so forth in order to suppress diffusion of the basic species. In addition, there are cases when the removal of this protective film following patterning of the resist film requires an etching agent that differs from the developing solution of the resist, thereby resulting in the problem of causing the process to become excessively complex.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a chemically amplified resist material, which is able to suppress pattern defects in a chemically amplified resist film caused by external basic species without increasing the complexity of the production equipment and process, and a patterning method that uses this chemically amplified resist material.
The chemically amplified resist material according to the present invention is a resist material comprising a base resin and a photo acid generator having sensitivity at the wavelength of patterning exposure; the chemically amplified resist material further comprising an activator that generates an acid or a radical by a treatment other than the patterning exposure.
The patterning method according to the present invention is a patterning method in which a resist pattern is transferred to an underlying film or layer by photolithography followed by patterning of the film or layer, and comprises the formation of the resist pattern by a step in which a resist film is formed from the chemically amplified resist material of the present invention on a substrate provided with the film or layer to be patterned on its surface, a step in which treatment is performed in which an acid or a radical is generated from an activator in the resist film, a step in which the resist film is exposed in a predetermined pattern, and a step in which the exposed resist film is baked and developed to form a resist pattern.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a chemically amplified resist material that is able to suppress pattern defects of a resist film caused by external basic species. This chemically amplified resist material contains a base resin and a photo acid generator having sensitivity at the wavelength of patterning exposure that generates, as a result of exposure, an acid which functions as a catalyst during subsequent baking, and as a result of alkaline solubilization (in the case of a positive resist) or alkaline insolubilization (in the case of a negative resist) of the exposed portion due to the catalytic action of the acid, a resist pattern can be formed by an alkaline developing solution, with the chemically amplified resist material also containing, in addition to the base resin and photo acid generator, an activator that generates an acid or a radical by a separate treatment from patterning exposure.
The base resin in the chemically amplified resist material of the present invention may be any base resin used in an ordinary chemically amplified resist material. In the case of the resist material of a negative resist, the base resin contains a crosslinking agent or curing agent for making the base resin insoluble in the alkaline developing solution by reacting with it.
The photo acid generator contained in the chemically amplified resist material of the present invention is a substance that is directly involved in patterning by this resist material, and generates an acid as a result of patterning exposure. Various types of compounds known in the field of chemically amplified resist materials can be used for the photo acid generator in the resist material of the present invention. Examples of such photo acid generators include onium salt compounds, organic halogen compounds sulfone compounds and sulfonate compounds, and any of these can be used in the chemically amplified resist material of the present invention.
The activator used in the chemically amplified resist material of the present invention is a substance that generates an acid or a radical by a treatment that is different than the patterning exposure that generates an acid from a photo acid generator. This activator generates an acid or a radical by a treatment in a step prior to patterning exposure, and suppresses pattern defects in the resist film that occur when basic species are present during patterning exposure by neutralizing external basic species present in the resist film, and particularly near the surface layer portion of the film and near the interface between the film and an underlying film, prior to patterning exposure (prior to generation of acid required for patterning of the resist film from the photo acid generator).
The activator used in the present invention generates an acid or a radical used for neutralization of basic species present in the resist film by decomposition. In order to decompose an activator in the resist film, the resist film is subjected to, prior to patterning exposure, a treatment separate from the patterning exposure.
In order to decompose the activator and generate an acid or a radical, it is preferable to use a thermal acid generator or thermal radical generator as an activator. Examples of thermal acid generators include aliphatic sulfonic acids, aliphatic sulfonates, aliphatic carboxylic acids, aliphatic carboxylates, aromatic sulfonic acids, aromatic sulfonates, aromatic carboxylic acids, aromatic carboxylates, metal salts, phosphate esters and acid-breeding agents as described in Japanese Unexamined Patent Publication No. 8-248561 that are thermally unstable and decompose at comparatively low temperatures. Examples of thermal radical generators include various compounds known to be initiators of radical reactions, such as peroxides and azo compounds.
Thermal acid generators and thermal radical generators are required to be used for neutralization of basic species within the resist film by decomposing prior to patterning exposure. Preferably, thermal acid generators and thermal radical generators are decomposed during formation and baking of the resist film after coating the resist material onto a substrate. Thus, the decomposition temperature of the thermal acid generator or thermal radical generator is preferably equal to or below the baking temperature during formation of the resist film. In consideration of the decomposition temperature of the photo acid generator used for patterning the resist film and the softening temperature of typical base resins, the baking temperature during formation of the resist film is preferably within the range of 90-200° C. and, accordingly, a substance that decomposes at about 70-180° C. is preferably selected for the thermal acid generator or thermal radical generator.
Substances that generate an acid or a radical when irradiated by rays (namely, photo acid generators or photo radical generators) can also be used as an activator. In this case, the resist film is exposed to rays at a wavelength to which the photo acid generator used for patterning the resist film does not have sensitivity, and as a result, the activator decomposes to generate an acid or a radical. In order to accomplish this, a step is required in which the entire surface of the resist film is irradiated with radiation at a wavelength that differs from that for the patterning exposure prior to the patterning exposure to decompose the activator. In addition, after irradiating the entire surface, a baking step may be added to promote neutralization of basic species near the surface layer of the resist film and near the interface with the underlying substrate by the generated acid.
The radiation to generate an acid or a radical by decomposing a photo acid generator or photo radical generator is preferably visible rays, ultraviolet rays, an electron beam, X-ray or a convergent ion beam. In addition, in consideration of the resolution performance of the resist material, the absorbance of the resist film at the wavelength of the radiation is preferably 1.75 or less.
It is preferable that the number of molecules of acid or radical generated by decomposition of the activator be no more than one-fifth the number of molecules of acid generated by decomposition of the photo acid generator due to subsequent patterning exposure. If the number of molecules of acid or radical generated by decomposition of the activator is more than one-fifth the number of molecules of acid generated from the photo acid generator due to patterning exposure, a reaction with the base resin may occur that is equivalent to that when ordinary patterning exposure is performed (resulting in the generation of acid by decomposition of the photo acid generator) at the stage of neutralization of basic species, namely at the stage prior to patterning exposure, thereby preventing the desired patterning for solubilization of the entire surface of the resist film in the case of a positive resist material, or insolubilization of the entire surface of the resist film in the case of a negative resist material.
Thus, an activator is added to the resist material in an amount such that the number of molecules of acid or radical generated by its decomposition is no more than one-fifth the number of molecules of acid generated from the photo acid generator due to subsequent patterning exposure. However, even though this is the case, as the number of molecules of acid or radical generated by decomposition of the activator fluctuates depending on the treatment conditions for decomposition of the activator (e.g., heating temperature and heating time in the case of an activator decomposed by heat, or wavelength of the radiated rays and exposure time in the case of an activator decomposed by rays), the amount of activator actually used must be determined in consideration of the type and decomposition treatment conditions of activator, as well as the resist system to which the activator is added (the number of molecules of acid generated from the photo acid generator varies for each resist system), and that amount can be easily determined by simple experimentation.
The chemically amplified resist material of the present invention can be easily prepared by adding an activator to an existing chemical resist material in an amount such that the number of molecules of an acid or a radical generated by decomposition thereof is no more than one-fifth the number of molecules of acid generated from the photo acid generator due to subsequent patterning exposure. Even in the case of designing a new chemically amplified resist material, the blending of base resin and photo acid generator may be similarly determined followed by addition of activator.
In the case of patterning an underlying film or layer with the chemically amplified resist material of the present invention, a resist film comprised of a chemically amplified resist material can be formed on an underlying film or layer, an acid or a radical is generated from the activator in the resist film by heating or by irradiating with rays at a wavelength effective for decomposing the activator, the resist film is exposed in a predetermined pattern, a resist pattern is formed by baking and developing, and then the underlying film or layer can be patterned by photolithography using the resist pattern as a mask.
Although the chemically amplified resist and pattering method using that resist of the present invention are naturally effective in suppressing pattern defects in the surface layer portion of the resist pattern caused by basic species from the atmosphere, they are also extremely effective in suppressing pattern defects near the interface between the resist film and the underlying film or layer caused by basic species contained by the underlying film or layer to which the resist pattern is to be transferred. Examples of underlying films or layers that contain basic species include films or layers formed from SiN, SiON, TiN, BPSG, BSG or PSG.
EXAMPLES
Although the following provides a more detailed explanation of the present invention through its examples, the present invention is not limited to these examples.
The term “parts” used in the following examples refers to “parts by weight” unless specified otherwise.
The following substances were made available for use as constituent substances of a resist material.
1. Base Resins
1-1 Polyvinylphenol/t-butylacryalte (50/50) copolymer 1-2 Polyvinylphenol
2. Crosslinking Agent
2-1 Hexamethoxymethyl melamine
3. Photo acid generators
3-1 Triphenylsulfonium triflate 3-2 Diphenyliodonium triflate 3-3 Compound represented with the following formula (I):
4. Thermal acid generators
4-1 2-nitrobenzyl tosylate 4-2 N-(10-camphorsulfonyloxy)succinimide
5. Thermal radical generator
5-1 Dimethyl-2,2′-azo-bis-isobutyrate
6. Solvent
6-1 Propylene glycol monomethyl ether acetate
Example 1
The following substances were mixed to prepare coating liquids 1-3 having different thermal acid generators.
Base resin: 1-1 (100 parts) Thermal acid generators:
None—Coating liquid 1 (comparative example) 4-1 (5 parts)—Coating liquid 2 4-2 (5 parts)—Coating liquid 3
Solvent: 6-1 (500 parts)
The following process was carried out using the above coating liquids.
(1) Coating liquid was spin coated onto an Si substrate followed by baking for 60 seconds at 80-130° C.
(2) Dissolving speed of the coated film was measured using a 4% aqueous tetramethylammonium hydroxide solution.
The relationship between film formation temperature and the dissolving speed of the film is shown in Table 1.
TABLE 1
Formation
Dissolving speed (nm/sec)
temperature
Coating liquid
Coating liquid
Coating liquid
(° C.)
1
2
3
80
0.04
0.02
0.02
90
0.04
0.02
0.15
100
0.03
0.2
7.5
110
0.03
15
>10 3
120
0.03
>10 3
>10 3
130
0.03
>10 3
>10 3
Based on the solubilization of the base resin, the decomposition temperatures of thermal acid generators 4-1 and 4-2 were judged to be 120° C. and 110° C., respectively.
Example 2
The following substances were mixed to prepare positive resists 4 through 8 having different added amounts of thermal acid generator 4-1. The amounts of thermal acid generator 4-1 added to positive resists 4 through 8 were 0, 10, 20, 30 and 40 mol %, respectively, with respect to the amount of photo acid generator 3-1.
Base resin: 1-1 (100 parts) Photo acid generator: 3-1 (5 parts) Thermal acid generator: 4-1 Solvent: 6-1 (500 parts)
The following process was carried out using the above resists.
(1) The positive resist was spin coated onto an Si substrate on which was formed an SiN film at a thickness of 100 nm followed by baking for 60 seconds at 120° C. to form a resist film.
(2) The resist film was exposed in a line and space pattern having a width of 0.2 μm and pitch of 0.4 μm using a KrF excimer laser (wavelength=254 nm) exposing apparatus (exposure dose: 20 mJcm −2 ).
(3) Following exposure, the resist film was baked for 60 seconds at 110° C. (post-exposure baking (PEB)).
(4) The resist film was then developed for 60 seconds with 2.38% aqueous tetramethylammonium hydroxide solution.
As a result, although the formation of a T-top and footing occurred in Resist 4 (Comparative Example) thereby preventing resolution of the pattern, the resist pattern was resolved directly from the upper surface to the substrate in resists 5 and 6. In resists 7 and 8, the entire surface of the resist was solubilized thereby preventing pattern formation.
Example 3
The following substances were mixed to prepare positive resists 9 through 13 having different added amounts of thermal acid generator 4-2. The amounts of thermal acid generator 4-2 in positive resists 9 through 13 were 0, 10, 20, 30 and 40 mol %, respectively, with respect to the amount of photo acid generator 3-2.
Base resin: 1-1 (100 parts) Photo acid generator: 3-2 (5 parts) Thermal acid generator: 4-2 Solvent: 6-1 (500 parts)
The following process was carried out using the above resists.
(1) The positive resist was spin coated onto an Si substrate on which was formed an SiO 2 film at a thickness of 50 nm followed by baking for 60 seconds at 110° C. to form a resist film.
(2) The resist film was exposed in a line and space pattern having a width of 0.15 μm and pitch of 0.3 μm using an electron beam exposing apparatus having an acceleration voltage of 50 keV (exposure dose: 10 μCcm −2 ).
(3) Following exposure, the resist film was baked for 60 seconds at 100° C. (post-exposure baking (PEB)).
(4) The resist film was then developed for 60 seconds with 2.38% aqueous tetramethylammonium hydroxide solution.
As a result, although footing occurred in Resist 9 (Comparative Example) thereby preventing resolution of the pattern, the resist pattern was resolved directly from the upper surface to the substrate in resists 10, 11 and 12. In resist 13, the entire surface of the resist was solubilized thereby preventing pattern formation.
Example 4
The following substances were mixed to prepare positive resists 14 and 15.
Base resin: 1-1 (100 parts) Photo acid generator: 3-1 (5 parts) Radical generator: None—Resist 14 5-1 (0.5 parts)—Resist 15 Solvent: 6-1 (500 parts)
The following process was carried out using the above resists.
(1) The positive resist was spin coated onto an Si substrate on which was formed a BPSG film at a thickness of 500 nm followed by baking for 60 seconds at 110° C. to form a resist film.
(2) The resist film was exposed in a line and space pattern having a width of 0.2 μm and pitch of 0.4 μm using a KrF excimer laser (wavelength=254 nm) exposing apparatus (exposure dose: 20 mJcm −2 ).
(3) Following exposure, the resist film was baked for 60 seconds at 100° C. (post-exposure baking (PEB)).
(4) The resist film was then developed for 60 seconds with 2.38% aqueous tetramethylammonium hydroxide solution.
As a result, although the formation of a T-top and footing occurred in Resist 14 (Comparative Example) thereby preventing resolution of the pattern, T-top and footing were improved in Resist 15 and the pattern was able to be resolved.
Example 5
The following substances were mixed to prepare negative resists 16 and 17.
Base resin: 1-2 (100 parts) Crosslinking agent: 2-1 (10 parts) Photo acid generator: 3-1 (5 parts) Thermal acid generator: None—Resist 16 4-1 (10 mol % with respect to photo acid generator 3-1)—Resist 17 Solvent: 6-1 (500 parts)
The following process was carried out using the above resists.
(1) The negative resist was spin coated onto an Si substrate on which was formed a TiN film at a thickness of 80 nm followed by baking for 60 seconds at 120° C. to form a resist film.
(2) The resist film was exposed in a line and space pattern having a width of 0.15 μm and pitch of 0.3 μm using an electron beam exposing apparatus having an acceleration voltage of 50 keV (exposure dose: 15 μCcm −2 ).
(3) Following exposure, the resist film was baked for 60 seconds at 110° C. (post-exposure baking (PEB)).
(4) The resist film was then developed for 60 seconds with 2.38% aqueous tetramethylammonium hydroxide solution.
As a result, although the pattern was disturbed due to the occurrence of undercutting in Resist 16 (Comparative Example), the resist pattern was resolved directly from the upper surface to the substrate in Resist 17, and a pattern was able to be formed.
Example 6
The following substances were mixed to prepare positive resist 18.
Base resin: 1-1 (100 parts) Photo acid generator (1): 3-1 (5 parts) Photo acid generator (2): 3-3 (0.5 parts) Solvent: 6-1 (500 parts)
Among the photo acid generators used in this example, photo acid generator 3-1 is not sensitive to ultraviolet rays at a wavelength of 300 nm or longer.
The following process was carried out using the above resist.
(1) The positive resist was spin coated onto an Si substrate on which was formed an SiN film at a thickness of 100 nm followed by baking for 60 seconds at 110° C. to form a resist film.
(2) The entire surface of the resist film was exposed for 1 minute with a g-line lamp (wavelength=365 nm) (exposure dose: 100 mJcm 2 ).
(3) The resist film was baked for 60 seconds at 110° C.
(4) The resist film was exposed in a line and space pattern having a width of 0.2 μm and pitch of 0.4 μm using a KrF excimer laser (wavelength=254 nm) exposing apparatus (exposure dose: 20 mJcm −2 ).
(5) Following exposure, the resist film was baked for 60 seconds at 100° C. (post-exposure baking (PEB)).
(6) The resist film was then developed for 60 seconds with 2.38% aqueous tetramethylammonium hydroxide solution.
As a result, although the formation of a T-top and footing occurred that prevented resolution of the pattern when steps (2) and (3) of the above process were not carried out (Comparative Example), when the entire process was carried out, the resist pattern was resolved directly from the upper surface to the substrate.
As has been explained above, according to the present invention, a fine resist pattern can be formed while suppressing pattern defects of a chemically amplified resist film caused by basic species from the outside, and an underlying film or layer on which microfabrication is to be performed can be patterned to predetermined dimensions using this resist pattern. The present invention is particularly effective in the case the underlying film or layer to which a resist pattern is to be transferred contains basic species that cause pattern defects in a chemically amplified resist film. | A chemically amplified resist material comprising a base resin and a photo acid generator having sensitivity at the wavelength of patterning exposure; wherein, the chemically amplified resist material further comprising an activator that generates an acid or a radical by a treatment other than the patterning exposure. A patterning method using the same is also disclosed. | 8 |
This invention relates to the handling of masonry blocks in particular and more specifically to the conveyance and positioning of such blocks for assembly into multi-tiered stacks or cubes.
BACKGROUND OF THE INVENTION
It is customary for manufacturers of masonry blocks to assemble them into multi-tiered stacks or cubes for ease of handling and shipping. The blocks of each tier are often stagger-stacked in relation to the blocks in the tiers above and below to provide overlapping structural support in the stack. The staggered relation is achieved by assembling the blocks in each tier in a pattern that is different than, but which complements the pattern of, adjacent tiers.
Automated handling equipment is conventionally used to assemble the blocks in the above fashion. Typically, the blocks are conveyed along a transport line in single line, side-by-side succession to a patterning station where they are reoriented, a row- at-a-time, according to the particular tier pattern being assembled, and then are conveyed onward to a cubing station where they are off-loaded, row-by-row, by a push bar sweep onto an adjacent platform for assembly into the cube.
It is of course desirable that the cubing of the blocks be carried out as quickly and with as few steps as possible to maximize productivity and minimize cycling of the patterning and cubing station equipment.
Multi-turntable devices are often employed at the patterning station. A plurality of turntables are arranged longitudinally along a stationary conveyor bed in the direction of conveyance. The blocks arriving at the patterning station are transported by a dragbar conveyor or the like into position on the turntables, with the required number of turntable positions being provided to accommodate an entire row of the blocks at the positioning station at one time. The turntables are selectively rotated to reorient the blocks to the desired row pattern.
A similar multi-turntable station is shown in Thomas et al U.S. Pat. No. 4,205,742, wherein masonry blocks are fed in multiple single-line side-by-side rows to multiple turntables, but in the lateral rather than longitudinal direction of the turntables. FIG. 1 of the Thomas patent depicts two alternating tier patterns for use in assembling standard sized 8"×16" masonry blocks into a cube measuring 40"×48" on side.
FIG. 2 of the present application illustrates other tier patterns that are common when employing a longitudinally fed multi-turntable device at the patterning station to assemble 40"×48" cubes. It will be appreciated that the second tier pattern from the right in FIG. 2 would be difficult to assemble using the laterally fed turntable station of Thomas, unless a fourth turntable position were added. Similar difficulty arises with longitudinally fed turntable devices. Considering the patterning of the bottom-most row of the second tier pattern to the right in FIG. 2, for example, two turntable positions are required for each of the endmost blocks and two additional turntable positions are needed to handle the two intermediate block pairs of the row. To assemble such a pattern according to conventional practice, six of the side-by-side blocks are conveyed into position on their respective turntables and the middle two tables are rotated 90° to reorient the intermediate block pairs lengthwise as called for by the row pattern before the blocks are conveyed onward and off-loaded at the cubing station.
It will be appreciated that the first and second rows of blocks of the same tier pattern are required to be handled as individual rows rather than patterned together as a single row. Considering the patterning of the upper row according to conventional practice, for example, three individual side-by-side blocks are conveyed into position on each of three turntables and then rotated 90° to reorient them end-to-end for off-loading at the cubing station. The second row passes untouched through the patterning station and is off-loaded. In total, ten manipulative steps are required according to conventional practice to convey, reposition, and off-load the blocks that make up the second tier pattern of FIG. 2. The fourth and fifth tier patterns to the right of FIG. 2 require eight such steps with the middle and bottom rows, respectively, being handled separately from their adjacent rows.
Similar difficulties arise when assembling standard masonry blocks in larger 48"×48" cubes, three common tier patterns of which are illustrated in FIG. 3 of the application. It will be seen by comparison of the tier patterns of FIGS. 2 and 3 that certain block patterns are recurring, with some of the blocks extending end-to-end in a row, whereas others are arranged side-to-side. A four position turntable and twelve manipulative steps are presently required to assemble the third tier pattern of FIG. 3.
It is an object of the present invention to reduce the number of manipulative steps and turntable positions required to assemble such tier patterns.
It is a further object to achieve the above stated objectives together by prepositioning the blocks ahead of the patterning station for a more efficient operation of the patterning and cubing stations.
SUMMARY OF THE INVENTION AND ADVANTAGES
The above objects are achieved according to the invention by appreciating first of all that all or some of the rows of blocks of each tier pattern (except the base courses to the far left in FIGS. 2 and 3) can be considered as being comprised of multiple groupings of three blocks, each arranged in a so-called "tie pattern" (depicted in FIG. 4) in which two of the blocks in each group are arranged side-by-side and the third is disposed crosswisely to them at one end of the side-by-side pair. Considering, for example, the second and third tier patterns of FIG. 2, it will be seen that there are two rows of such tie-patterned groupings in each tier. The fourth and fifth tier patterns of FIG. 2 each have one row of tie-patterned blocks and one row of side-by-side blocks. The second and third tier patterns of FIG. 3 are each made up of two rows of tie-patterned blocks.
According to the invention, the blocks are preoriented into tie-patterned groupings ahead of the patterning station. The patterning station is then able to handle the blocks in such tie-patterned groupings.
The prepositioning and handling of the blocks in tie-patterned groupings has the advantage of reducing the number of turntable positions required to assemble the tier patterns. Considering, for example, the bottom-most row of the second tier pattern of FIG. 2, only two turntable positions are now required, whereas four positions are needed according to conventional practice.
Another advantage of handling the blocks in tie-patterned groupings is that the tiers are able to be assembled in far fewer steps than are required in conventional practice. Whereas conventionally it would take ten steps to assemble the second tier pattern of FIG. 3, handling the blocks in tie-patterning groupings according to the invention reduces the number of steps to six.
According to a preferred embodiment, the prepositioning station includes a block metering device which operates to hold up the line of incoming blocks and then releases them in groups of three toward a lift and turn device at the station. The leading-most block in the group is allowed to pass by the lift and turn platform of the new device, after which the platform is elevated to lift the trailing pair of blocks above the conveyor line, rotate them 90°, and then deposit them back onto the conveyor line in the desired tie-patterned relation to the leading block for conveyance onward toward the patterning station. The process is repeated for subsequent groupings.
At the patterning station, the tie-patterning groupings are each conveyed into position on an associated turntable, and the turntables are rotated as needed to reorient the groupings in the desired row pattern called for by the particular tier being assembled. Blocks that are not to be tie-patterned are allowed to pass undisturbed through the block positioning station for handling in the conventional manner by the patterning and cubing stations.
These and other objects and features of the invention will become apparent by reference to the following specification and drawings.
THE DRAWINGS
A presently preferred embodiment of the invention is disclosed in the following description and in the accompanying drawings, wherein:
FIG. 1 is a block diagram illustration of the overall block handling system of the invention;
FIGS. 2 and 3 are diagrammatic illustrations of various tier pattern arrangements of blocks that may be employed in assembling standard masonry blocks in cubes measuring 40"×48" and 48"×48", respectively;
FIG. 4 is a diagrammatic illustration of a "tie-patterned" grouping of three blocks;
FIG. 5 is a schematic plan view of the block prepositioning station;
FIG. 6 is a fragmentary perspective view of the block prepositioning station;
FIG. 7 is a plan view of the lift and turn device of the prepositioning station;
FIG. 8 is a cross-sectional view taken along line 8--8 of FIG. 7 and illustrating the platform in the lowered position;
FIG. 9 is a view like FIG. 8 but showing the platform raised to an elevated position;
FIG. 10 is a cross-sectional view taken along line 10--10 of FIG. 7;
FIG. 11 is a plan view of FIG. 9 illustrating the 90° indexing of the platform between two positions;
FIG. 12 is a fragmentary plan view of the lift and turn conveyor system;
FIG. 13 is a longitudinal sectional view of the lift and turn conveyor system taken along line 13--13 of FIG. 12;
FIG. 14 is a lateral section view of the lift and turn conveyor system taken along line 14--14 of FIG. 12;
FIG. 15 is a schematic plan view showing tie-patterned groups of blocks conveyed into position on respective turntables at the patterning station;
FIG. 16 is a view like FIG. 15 but illustrating the tie-patterned blocks reoriented according to a predetermined row pattern; and
FIG. 17 is a schematic plan view of the reoriented block groups of FIG. 16 shown conveyed onward to the cubing station in preparation for off-loading onto an adjacent stack.
DETAILED DESCRIPTION
A general overview of the components and layout of a masonry block cubing line according to the invention is shown in the schematic flow diagram view of FIG. 1, wherein standard rectangular masonry blocks B, each measuring 8"×16" on side (or their rectangular equivalent) are conveyed from a production source 10 (e.g., a block turnover and splitter station) in single line side-by-side succession in the direction of arrow A along a conveyor line 12 toward a cubing station 14 at the end of the line where the blocks B are off-loaded and assembled into multi-tiered stacks or cubes C measuring on side a multiple of the width and length dimensions of the blocks B.
FIGS. 2 and 3 depict various tier patterns that may be employed for assembling such masonry blocks B into cubes C measuring 40"×48" and 48"×48" on side, respectively. It will be apparent from an inspection of FIGS. 2 and 3 that at least some of the rows of blocks (as viewed from left to right) are made up of multiple groupings T of three blocks each arranged in a so-called "tie pattern" order, as illustrated in FIG. 4, in which two of the blocks in the group are side-by-side and the third block lies cross-wise at one end of the side-by-side pair.
Up-line of the cubing station 14 is a patterning station 15, and up-line from that is a block prepositioning station 16. According to the invention, blocks to be assembled at the cubing station 14 into rows containing such tie-patterned groupings are pre-oriented at the prepositioning station into such tie-patterned groupings T upstream from patterning station 15 to achieve the desired row pattern.
Referring now more particularly to FIGS. 5 and 6, the line of blocks B arriving at the prepositioning station 16 in their initial side-by-side relation are received on the power infeed conveyor 20 of a block metering device 18 at the station 16. The conveyor 20 includes a series of conveyor rollers 22, journaled at their ends by a main frame 24 and coupled for conjoint driven rotation by a common drive chain and motor (not shown). Guides 26 center the block B on the rollers 22 for passage between a pair of laterally opposed block clamps 30 mounted on the frame 24 and coupled to hydraulic rams 32.
When the blocks B arriving at the prepositioning station are to be tie-patterned in accordance with the predetermined pattern of the tier in which they are to be assembled, the metering device 18 is controlled to accumulate an abutting backlog of the blocks on the conveyor, as illustrated in FIG. 5, which are then released in groups of three at a time for conveyance onward to a lift and turn device 36 provided for the station 16.
The backlog may be achieved by operating the rams 32 to displace the block clamps 30 inwardly to the solid line, block clamping position shown in FIG. 5, in order to engage with compressive force the leading block on the conveyor 20 as it arrives between the clamps 30. Clamping the leading block halts its movement and causes the blocks behind to abut and accumulate on the conveyor 20.
The grouped release of the blocks B from the metering device 18 is achieved by retracting the block clamps 30 to a block releasing position (broken chain line position in FIG. 5) out of engagement with the leading block for a time period sufficient to enable the conveyor 20 to drive the forward three blocks past the clamps, after which the clamps are returned to their block engaging position to halt the conveyance of any further blocks at this time.
Blocks that are released from the metering device 18 are received on an index conveyor 34 of the lift and turn device 36 arranged immediately downline of the infeed conveyor 20. The index conveyor 34 includes a support frame 38 having longitudinal side rails 39, 40, and an intermediate frame structure 41, which journal a series of power driven rollers. As shown best in FIG. 7, a leading group 42 and trailing group 43 of rollers are transversely full length and extend continuously between the side rails 39, 40. Between the end groups of rollers 42, 43 are a group of segmented rollers which are divided into left and right hand roller sets 44, 45 (FIG. 12), journaled at their outer ends by the rails 39, 40 and at their inner ends by the intermediate frame structure 41. The rollers 44, 45 are spaced to define a cruciform-shaped opening 46 through the conveyor 34 to accommodate a similar cruciform-shaped platform 50 between the rollers, the operation and purpose of which will be described presently.
FIGS. 12-14 illustrate the drive system for the index conveyor 34. Referring to FIG. 14, a hydraulic drive motor 52 is mounted by a bracket 54 to a cross member 56 of the frame 38 beneath the rollers. A horizontal drive shaft 58 extends laterally across the conveyor from opposite sides of the motor 52 and carries dual sprocket sets 60, 62 at its opposite ends.
Referring now to FIG. 12, the leading and trailing rollers of the groups of end rollers 42, 43 carry dual sprocket sets 63 on one end thereof, and the rollers therebetween each carry a single sprocket 64. These are successively arranged in laterally staggered relation to accommodate a close spacing of the rollers and the longitudinal overlap of the sprockets 64. A continuous double wide drive chain 65 is enmeshed with the drive sprockets 62 and is trained about the dual sprocket sets 63 of the endmost groups of rollers 42, 43 as well as each of the staggered sprockets 64 of the intermediate rollers. The staggering of the sprockets 64 is such that they are caused to engage one side or the other of the double width chain 65.
It will be appreciated that the drive chain 65 is able to drive all but the intermediate set of rollers 45 on the opposite side of the conveyor. Those are driven in similar manner by a second double wide drive chain 66. As shown best in FIG. 12, the leading and trailing rollers of the intermediate roller set 45 carry dual sprocket sets 67 and the intervening rollers carry single sprockets 68 which are staggered in the same manner as sprockets 64. The chain 66 is enmeshed with dual sprockets 60 of the drive shaft 58 and then trained about the sprockets 67, 68 of the intermediate roller set 45 so that all rollers are driven conjointly upon operation of the motor 52.
Turning to FIG. 5, the group of blocks released from the metering device 18 are transported by the conveyor 34 toward the lift and turn device 36. A photo switch or other suitable position sensor 69 is located on the frame 38 in position along the conveyor to sense when the last block in the group has passed beyond the block clamps 30. The sensor 69 preferably comprises part of a larger computerized control system which includes a PLC 70 that operates in response to receiving the signal from the sensor 69 to halt the drive of the infeed rollers 22 and extend block clamps 30 to their block engaging positions to prevent any additional blocks from passing through beyond the metering station 18. The programmed controller 70 is conventional and the details of the control circuitry form no part of the present invention and need not be described.
Downline of the sensor 69 is another sensor 71 of the same or equivalent type supported by the frame 38 in position to sense when the leading block in the group has moved beyond the platform 50, which in turn corresponds to the simultaneous arrival of the trailing pair of blocks in the group into position over the platform 50. This position of the blocks is illustrated in FIG. 5. The sensor 71 signals the PLC 70 which in turn actuates a lift and turn mechanism 72 to raise the platform 50 from its initial lowered position, recessed within the opening 46 of the conveyor 34 at a level below the upper support plane P of the conveyor 34 (illustrated by chain lines in FIG. 8), to a raised position above the plane P (illustrated in FIG. 9), causing the trailing pair of blocks in the group to be engaged from below and lifted by the platform 50 off the conveyor 34. Once elevated, the platform 50, and thus the block pair, is rotated or indexed, as illustrated in FIG. 6, 90° from its initial orientation, and the platform 50 then is lowered to deposit the trailing pair of blocks back on the conveyor 34, but now repositioned in the desired tie-pattern orientation with their length dimensions now aligned with the direction of conveyance A so that they can be conveyed onward toward the patterning station 15.
The sensor 71 senses when the repositioned trailing blocks have cleared the platform 50. In response, the PLC 70 actuates the index conveyor 20 and block clamps 30 to release the next successive group of three blocks from the metering station to be tie patterned at the prepositioning station 16.
The preferred construction of the lift and turn mechanism 72 is illustrated in FIGS. 8-11. As shown best in FIGS. 10 and 11, the mechanism 72 includes a stationary mounting beam 74 that is fixed at its ends by suitable fasteners 75 or the like to laterally opposed frame sections 38a, 38b of the frame 38 in position beneath the opening 46. A vertical lift shaft assembly 76 extends through a central opening 78 in the beam 74 and is supported in vertically slidable relation thereto by means of bearing flanges 80 above and below the beam 74. The shaft 76 mounts the platform 50 at its upper end and is coupled at its lower end to a lifting mechanism 82 (FIG. 8) and a rotary index mechanism 84, both of which are under the control of the PLC 70.
As shown best in FIGS. 8 and 9, the lifting mechanism 82 comprises a hydraulic cylinder 86, mounted vertically on a horizontal swing plate 88, and having a rod 87 extending from the cylinder 86 and coupled at its free end to one leg 90a of a linkage 90 pivotally supported by the swing plate 88. The other leg 90b of the linkage 90 is coupled to the lower end of the shaft assembly 76. As illustrated in FIG. 8, retracting the rod 87 of cylinder 86 acts to rock the linkage 90 in one direction raising leg 90a and lowering leg 90b, which in turn lowers shaft assembly 76 to move the platform 50 to the lowered position. Extending the rod 87 from the cylinder 86 rocks the linkage 90 in the opposite direction to elevate the shaft assembly 76 and platform 50 to the raised position above the conveying plane P, as illustrated in FIG. 9.
The construction and operation of the rotary index mechanism 84 is best illustrated in FIGS. 10 and 11. The rotary mechanism 84 includes a hydraulic cylinder 92 fitted with a threaded mounting yoke 94 at its base end for adjustable securement to the frame section 38a. A rod 95 projects from the cylinder 92 and carries a spherical coupling 96 at its free end which is attached to a lug 98 fixed to the swing plate 88 in radially spaced relation to the longitudinal rotary axis of the shaft assembly 76. Retracting the rod 95 of cylinder 92 under the control of the PLC 70 rotates the swing plate 88 and thus the shaft assembly 76 and platform 50 to the solid line position shown in FIG. 11. Extending the cylinder 92 rotates these components to the broken chain line position in FIG. 11 which is offset 90° from the solid line position. The platform 50 is retractable into the conveyor opening 46 when positioned in either of the two 90° indexed positions, enabling the platform 50 to alternate between the two positions in successive prepositioning operation cycles. It will be appreciated that the raising and lowering of the platform 50 is independent of its indexed position.
The tie pattern groupings T arriving at the patterning station 15 are identically arranged, with the leading block in each group extending crosswisely to the direction of product flow and the pair of associated trailing blocks extending in the direction of product flow (see FIG. 15). Block clamps 100 operate to accumulate a backlog of the groupings T ahead of the patterning station 15.
FIGS. 15 and 16 illustrate how the patterning station 15 may be operated to pattern, for example, the bottom row of the third tier pattern of FIG. 2. Three of such tie-patterned groupings are released by the block clamps 100 and are conveyed across a stationary bed 102 of a conventional unmodified multi-turntable patterning device 104 by means of a drag bar conveyor 106 or the like, into position on each associated turntable 108 as shown in FIG. 15. Once positioned, the bar conveyor 106 is backed up sufficiently to provide clearance for the rotation of the tier patterned groupings T as required. For the row illustrated, each turntable is rotated 90° clockwise to reorient the groupings T as shown in FIG. 16 according to the desired row pattern. The selection and degree of rotation of the turntables 108 is individually controllable and dependent on the row pattern to be developed.
Once the row of tie-patterned blocks T has been properly oriented in the desired row pattern, it is conveyed onward, as illustrated in FIG. 17, to the cubing station 14 where the row may be off-loaded by means of a conventional side pusher device 110 to an adjacent assembly platform 112 for assembling the cube C.
The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims. | Masonry blocks conveyed in side-facing-side relation toward a cubing station for assembling into multi-tiered stacks are fed to a prepositioning station where the blocks are separated into groups of three and the trailing two blocks in each group are reoriented 90° into a so-called tie pattern with the other block. The two trailing blocks remain in parallel relation and extend lengthwisely in the direction of conveyance. The tie-patterned groupings are fed to a patterning station where they are relatively repositioned as necessary into the arrangement predetermined by the particular tier pattern being assembled. Once properly oriented, the block groups are transferred to the cubing station. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to the field of rodent control and, more particularly, to a single use mousetrap that kills a mouse and encloses the carcass within a hermetically sealed disposable trap enclosure.
2. Description of the Related Art
Present methods of capturing or disposing of rodents are generally unsightly and unsanitary. One such method includes a snap-trap which has a spring operated bar for instantly killing the rodent. This type of trap includes a spring operated bar which is released by a trigger which is baited. Because of their “snapping” action, snap traps are dangerous to humans and pets as well as to rodents, because they can all be struck by it. Furthermore, as mice and other rodents are typically nocturnal animals such devices most frequently capture the animals at night or during periods when people are not around. As such, the rodent may lie in the trap for many hours before removal and disposal. In addition to being unsightly, such capture is unsanitary as rodents are known to carry disease-causing fleas and lice which leave the carcass on death, and bacteria which can spread after the animal is killed. These drawbacks can be serious problems around food handling areas.
Another method of disposing of the rodents is by using poisoned bait which kills the rodent, sometimes by dehydration. The baited traps are also dangerous to children and pets because they may be tempted to taste the bait. Another disadvantage of this method is that the rodent may crawl into some inaccessible area after eating the poison and die there. This prevents disposal of the dead rodent and can result in an unpleasant odor.
SUMMARY OF THE INVENTION
In view of the foregoing, the present invention is directed to a single use snap-trap enclosed within a hermetically sealing housing. The housing has an upper housing and a lower housing that are sealed together to define an airtight enclosure containing the snap-trap with a mouse entry opening. Fixedly connected to the lower housing is a modular base component having a specially designed structural configuration that integrates the setting/killing and door control mechanisms of the trap.
The setting/killing mechanism includes a setting/killing assembly having a setting axle with a setting bar and a kill bar attached thereto or integral therewith so as to rotate with said axle in a fixed relationship, a set spring, a setting handle, a trip latch and a bait pedal. The door control mechanism includes a door assembly and a door opening and closing gear mechanism having a combined axle and lever arm coupled to a spur gear that rotates therewith. The door assembly includes a torsional door spring and a rotationally mounted door that is configured to hermetically seal over the mouse entry opening. The door includes a cylindrical upper part with a central bore that defines the door rotational axis. One end of the cylindrical part is provided with a pinion gear that is operatively engaged with the spur gear so as to be rotated thereby. The torsional door spring is mounted on the door rotational axis with one end applying force against the inner surface of the door and the other end applying force against a front edge of the modular base component.
The setting/killing assembly is positioned in the lower housing inside the enclosure and is movable between a kill position and a set position by manipulation of the setting handle. The setting handle is operatively coupled to the setting axle but is positioned outside the enclosure. Rotation of the setting handle is resisted by the set spring which is tensioned between the lower housing and the kill bar. When the setting axle is moved to the set position by rotation of the setting handle, the set spring is loaded and the setting bar engages the lever arm. Further movement of the setting bar causes the lever arm to rotate on its axle and, in turn, rotate the spur gear and pinion gear which opens the door against the resistance of the torsional door spring.
The trip latch and bait pedal, both rotatably mounted on the setting axle, are configured to operate together to secure the kill and setting bars in the set position. Once set, subsequent movement of the bait pedal by a mouse serves to release the trip latch which, in turn, releases the set and kill bars. The kill bar and setting bar rotate together with the setting axle under the force of the loaded set spring to move rapidly to the kill position. With such rotation of the setting bar, the lever arm is released to counter-rotate on its axle, allowing the spur gear, under the force of the tensioned door spring, to counter-rotate, turning the pinion gear and closing the door. The door is provided with a rubber seal that mates with a flange on the inner wall of the housing to hermetically seal the enclosure with the dead mouse inside. The trap can then be disposed of safely without any contact between the user and the carcass and any parasites and/or pathogens associated therewith.
Accordingly, it is an object of the present invention to provide a single use enclosure-type mousetrap that can be hermetically sealed in a tripped condition in order to protect the user from any exposure to the dead mouse.
Another object of the present invention is to provide a snap-trap enclosed within a housing that is accessible only through a mouse access door and that is set from outside the housing.
A further object of the present invention is to provide a snap-trap in accordance with the preceding objects that includes a door opening and closing gear mechanism that automatically opens the door when the trap is placed in the set position and that automatically closes the door when the trap is triggered by a mouse.
A still further object of the present invention is to provide a snap-trap in accordance with the preceding objects that includes a spring-tensioned kill bar movable from a set position to a kill position to kill a mouse and simultaneously activate the door opening and closing gear mechanism to close the door and contain the carcass and any associated parasites and pathogens within the housing.
Still another object of the present invention is to provide a snap-trap in accordance with the preceding objects in which the door opening and closing gear mechanism includes a lever arm/axle combination coupled to a spur gear that engages a pinion gear on the door, the setting bar when rotated to the set position engaging the lever arm to rotate the gears and open the door while tensioning a door spring.
A further object of the present invention is to provide a snap-trap in accordance with the preceding objects in which rotation of the setting bar toward the kill position when the trap is triggered releases the lever arm, allowing the gears to counter-rotate and the door to close under the door spring tension.
Another object of the present invention is to provide a rodent trap that does not constitute a risk to humans and pets in the area, is easy to use and of simple construction, humanely kills the rodent, and enables the sanitary disposal of the dead rodent.
Yet another object of the present invention is to provide an enclosed snap-trap that is not complex in structure, is reliable in operation and which can be manufactured at low cost but yet efficiently kill and sealingly contain the dead mouse and associated parasites and pathogens.
These and other objects of the invention, as well as many of the intended advantages thereof, will become more readily apparent when reference is made to the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a hermetically sealing mousetrap in accordance with the present invention, with the upper housing shown as transparent to reveal the interior of the housing.
FIG. 2 is a perspective view of the mousetrap of FIG. 1 with the transparency of the upper housing removed.
FIG. 3 is a front view of the mousetrap of FIG. 2 .
FIG. 4 is another perspective view of the mousetrap of FIG. 2 , showing the front and right sides.
FIG. 5 is a top view of the mousetrap of FIG. 2 .
FIG. 6 is a perspective view of the upper housing of the mousetrap of FIG. 2 .
FIG. 7 shows an interior view of the access opening of the mousetrap of FIG. 2 as formed by upper and lower housings.
FIG. 8 is a perspective cutaway view of the door, sealing member and access opening of the mousetrap of FIG. 2 .
FIG. 9 is a perspective view of the upper portion of the access opening of FIG. 7 , shown with the upper housing upside down.
FIG. 10 is a view of the underside of the upper housing of FIG. 6 .
FIG. 11 is a perspective view of the bait plug of the mousetrap of FIG. 2 , showing the sealing O-ring.
FIG. 12 is a top perspective view of the bait plug of FIG. 11 .
FIG. 13 is a bottom perspective view of the bait plug of FIG. 12 .
FIG. 14 is an upper perspective view of the lower housing of the mousetrap of FIG. 2 .
FIG. 15 is a enlarged view of a portion of the lower housing of FIG. 14 including the lower portion of the access opening.
FIG. 16 is a perspective view of a through-going aperture in the lower housing of FIG. 14 .
FIG. 17 is a perspective view of the through-going aperture of FIG. 16 shown with the setting axle received therein and a sealing O-ring in accordance with the present invention.
FIG. 18 is a perspective view of the modular base component of the mousetrap of FIG. 1 .
FIG. 19 is another perspective view of the modular base component of FIG. 18 .
FIG. 20 is a perspective view of the setting/killing assembly of the mousetrap of FIG. 1 .
FIG. 21 is a top perspective view of the mousetrap of FIG. 1 , with the upper housing removed and showing the various operational components.
FIG. 22 is a perspective view of the outside of the setting handle of the mousetrap of FIG. 1 .
FIG. 23 is a perspective view of the inside of the setting handle of FIG. 22 .
FIG. 24 is a partial perspective view of the mousetrap of FIG. 1 , with the upper housing removed and showing certain of the operational components.
FIG. 25 is a perspective view of the trip latch of the mousetrap of FIG. 1 .
FIG. 26 is a side cutaway view of the mousetrap of FIG. 1 showing the trip latch as mounted therein.
FIG. 27A is a top perspective view of the bait pedal of the mousetrap of FIG. 1 .
FIG. 27B is a bottom perspective view of the bait pedal of FIG. 27A .
FIG. 28 is a perspective view of the door of the mousetrap of FIG. 1 .
FIG. 29 is a perspective view of the mousetrap components of FIG. 21 , shown in the set position.
FIG. 30 is a perspective view of the lever arm/axle combination of the door opening gear mechanism of the mousetrap of FIG. 1 .
FIG. 31 is a perspective view of the spur gear of the door opening gear mechanism of the mousetrap of FIG. 1 .
FIG. 32 is a perspective view of the position of the lever arm/axle combination of FIG. 30 when the trap is in the set position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Although only one preferred embodiment of the invention is explained in detail, it is to be understood that the embodiment is given by way of illustration only. It is not intended that the invention be limited in its scope to the details of construction and arrangement of components set forth in the following description or illustrated in the drawings. Also, in describing the preferred embodiments, specific terminology will be resorted to for the sake of clarity. It is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
As shown in FIG. 1 , the present invention is directed to an enclosed snap-trap for rodents generally designated by reference numeral 10 . The trap includes an upper housing generally designated by reference numeral 12 and a lower housing generally designated by reference numeral 14 that are sealed together to define an enclosure generally designated by reference numeral 16 . A bait hatch 18 is formed in the upper housing 12 and is sealed with a removable bait plug 20 . Secured to the lower housing is a modular base component 22 that integrates the setting/killing and door control mechanisms of the trap.
The setting/killing mechanism includes a setting/killing assembly generally designated by reference numeral 24 , a setting handle 26 , a set spring 266 (see FIG. 24 ), a trip latch 172 (see FIG. 26 ) and a bait pedal 32 . The door control mechanism includes a rotationally mounted door assembly generally designated by reference numeral 28 , and a door opening and closing gear mechanism generally designated by reference numeral 30 . While the trap as shown in FIG. 1 has a transparent upper housing to reveal the components inside the enclosure 16 for purposes of illustration, FIGS. 2-5 illustrate the assembled trap in various views with the upper housing 12 of a solid material as actually embodied for use.
As shown in FIGS. 2-6 , the upper housing 12 includes a flat front wall 34 , a flat top 36 , a rounded back wall 38 , rounded left and right sidewalls 40 , 42 and a hole in the top 36 forming the bait hatch 18 which is closed by the bait plug 20 . The left wall 40 has a recessed area 44 that accommodates the setting handle 26 when the trap is assembled. The adjacently located vertical ribs 46 are included for aesthetic reasons and are not part of the trap functionality.
The front wall 34 of the upper housing 12 has a cutout generally designated by reference numeral 48 therein (see FIG. 6 ) that forms the upper part of the door opening generally designated by reference numeral 50 (see FIG. 1 ) when the trap is assembled. As shown in FIGS. 7-9 , the cutout 48 has an inner flange or lip 52 which is the upper part of a door flange, generally designated by reference numeral 53 , that mates with a rubber seal 54 on the door 56 when the door 56 is closed. The door seal 54 is adhered to the outer surface 58 of the door and, when the door is closed, provides a hermetic seal against the mating door flange 53 as will be discussed further hereinafter. The bottom edge 60 of the upper housing 12 has a groove 62 , illustrated in FIG. 9 , that receives a raised triangular bead 144 on the top edge 142 of the lower housing 14 (see FIGS. 14 and 15 ) when the upper housing 12 and lower housing 14 are mated and ultrasonically welded together during the assembly process.
The interior of the upper housing, as shown in FIG. 10 , includes a dividing wall or barrier 66 that projects downwardly into the trap enclosure when the trap 10 is assembled. This barrier 66 aligns end-to-end with an upwardly projecting dividing wall 68 in the lower housing 14 (see FIG. 14 ) which, together with the barrier 66 , divides the trap enclosure substantially down the middle longitudinally in order to direct the mouse through the enclosure to the bait. Recessed area 45 forms the upper housing component of the setting handle recessed area 44 .
The bait hatch 18 is preferably located near the front of the trap and includes a round through-hole 70 with a recess 72 (see FIG. 6 ) that forms a sealing surface against which an O-ring 80 on the bait plug 20 , shown in FIG. 11 , is seated. The round through-hole 70 has two radial cutouts 82 that receive corresponding tabs 84 on the bait plug 20 , allowing the plug to be inserted into the hole. As viewed from the lower surface shown in FIG. 10 , the bait hatch 18 is further provided with protruding tabs 86 arranged in a clockwise direction from the cutouts 82 that prevent the bait plug 20 from being rotated counterclockwise during insertion. Located counterclockwise from the cutouts 82 are two posts 88 that serve as stops for the bait plug 20 once it has been inserted and rotated clockwise to the lock position.
The bait plug 20 , as shown in FIGS. 12 and 13 , includes a cap 90 with a handle 92 for rotating the plug during insertion and removal thereof. Attached to or integral with a lower surface 94 of the cap 90 is a cylindrical body 96 having a recess 98 therein for holding bait; preferably the bait is an adherent substance such as spreadable cheese or peanut butter. The lower surface 94 of the cap 90 forms a seating surface 100 for the O-ring 80 (not shown in FIG. 13 ) once the plug 20 is locked into the hatch 18 and includes a plurality of small pegs 102 that locate the O-ring 90 radially around the cylindrical body 96 for proper seating and sealing. Located axially around the cylindrical body 96 are the previously noted tabs 84 that slide through the cutouts 82 in the bait hatch 18 when the plug 20 is inserted.
Turning to FIGS. 14 and 15 , the lower housing 14 includes a flat bottom 104 , a flat front wall 106 , and a rounded back wall 108 . The front and back walls 106 , 108 are joined by substantially straight left and right side walls 110 , 112 with the left side 110 having a recessed area 114 that comes into abutment with the recessed area 45 in the upper housing 12 to receive the setting handle 26 when the trap is assembled. The lower housing recessed area 114 includes a through-going aperture 116 , shown in greater detail in FIG. 16 , for receiving the projecting end 248 of the setting axle 220 (see FIG. 20 ). The outside of this aperture has a rounded countersunk outer face 118 that provides a seating surface for the setting axle O-ring 120 shown in FIG. 17 .
The front wall 106 has a cutout generally designated by reference numeral 122 that forms the lower part of the door opening 50 and is aligned with the cutout 48 in the upper housing 12 when the trap is assembled to complete the door opening 50 . The door cutout 122 in the lower housing 14 also has a flange or a lip 124 that, together with flange 52 to form door flange 53 , mates with the rubber seal 54 on the door 56 when the door is closed to effect a hermetic sealing of the trap enclosure 16 (see FIG. 8 ). The inner surface 126 of the front wall 106 has associated mounting elements 128 (see FIG. 15 ) that serve to slidingly receive tabs 208 and 210 on the modular base component 22 to interlock component 22 with the lower housing 14 in order to enhance the door seal and increase the rigidity of the trap 10 .
The bottom 104 of the lower housing 14 includes the previously noted upwardly projecting dividing wall 68 that serves, along with the downwardly projecting wall 66 of the upper housing 12 , to divide the trap longitudinally and guide the mouse through the enclosure 16 . A further wall 69 is preferably provided that projects inwardly from the left side 110 toward the dividing wall 68 to funnel the mouse toward the bait pedal 32 . The lower housing 14 also includes two substantially symmetrical vertical support elements 134 having concave upper surfaces 136 that support the door opening and closing gear mechanism 30 , and two low profile strips 138 that raise the setting axle/kill bar 24 off the bottom 104 and work in conjunction with features on the modular base component 22 to accommodate the setting axle 30 . Positioned on the lower housing bottom 104 are a plurality of posts 140 that provide material to be melted down during a heat staking process that secures the modular base component 22 to the lower housing 14 during assembly. The upper and lower housings 12 , 14 are preferably made of molded plastic and are fused together using a conventional ultrasonic welding process as known by persons of ordinary skill in the art.
The top edge 142 of the lower housing 14 has a raised triangular bead 144 that mates with the groove 62 in the bottom edge 60 of the upper housing 12 for sealing of the upper housing 12 to the lower housing during the ultrasonic welding process.
The modular base component 22 is shown in FIGS. 18 and 19 and serves to integrate the trap setting and door opening elements within the housing and to facilitate assembly. The modular base component 22 includes a generally L-shaped base generally designated by reference numeral 146 which, as arranged in the trap when assembled and looking at the front wall 34 , can be described as having a left side generally designated by reference numeral 148 and a right side generally designated by reference numeral 150 .
The left side 148 of the base 146 includes a centrally located cutout 152 that divides the left side into a front part 154 and a back part 156 and is shaped to receive the setting axle 30 during assembly. On either side of the center cutout, arcuate vertical members 158 span the gap between the front and back parts 154 , 156 formed by the center cutout 152 . These arcuate vertical members 158 have rounded cutouts 160 therein that capture the setting axle 30 after trap assembly. The back part 156 of the left side 148 includes an upwardly projecting tubular member 162 concentrically arranged with a central tubular member 161 to define an annular channel 165 within which a spring 163 is mounted (see FIGS. 21 and 24 ). The spring 163 presses against the underside of the bait pedal 32 to assist in setting the trap as will be described more fully hereinafter.
The front part 154 of the left side 148 has two generally rectangular vertical planar elements 164 that extend linearly back from the front edge 166 toward the back part 156 . Aligned apertures 168 in each of these vertical planar elements 164 form a horizontal passageway that captures a metal pin 170 upon which a trip latch 172 (see FIGS. 25 and 26 ) rotates. The end of the pin 170 rests on a support block 174 (see FIGS. 18 and 19 ) that projects horizontally from the outer side of one of the vertical planar elements 164 . The trip latch 172 is further supported by its placement between the vertical planar elements 164 and an additional pair of vertically projecting arms 176 that are in linear alignment with the vertical planar elements 164 . These arms 176 also support a bridge portion 178 of the bait pedal 32 (see FIGS. 27A and 27B ) as will be described hereinafter.
Two spaced vertically oriented planar members 194 , 196 capture the door 56 and the door opening gear mechanism 30 . The outer member 194 is positioned adjacent the right edge 198 of the base and the inner member 196 is positioned inside the right edge 200 of the left side 148 . Each of these door capturing members 194 , 196 has an aperture 202 therein to receive the door axle 204 . The inner member 196 is further provided with a large centrally located opening 206 shaped like an archway that receives the axle, generally designated by reference numeral 296 , of lever arm/axle combination, generally designated by reference numeral 300 (see FIGS. 29 and 30 ). Each of the outer and inner members 194 , 196 also includes interlock tabs 208 , 210 that fit within the mounting elements 128 of the lower housing 14 to enhance the door seal and increase the rigidity of the structure. The inner member 196 also preferably includes an upper cutout 212 to allow visual alignment of the timing marks of the door opening and closing gear mechanism 30 during assembly as will be described hereinafter.
Spaced to the right of and generally parallel with the inner member 196 is an additional vertically oriented planar member 214 that defines space 306 therebetween. Planar member 214 also has a large centrally located opening 216 for capturing the spur gear 302 of door opening and closing gear mechanism 30 in cooperation with the inner member 196 in space 306 (see FIG. 32 ).
Finally, the base 146 includes a plurality of holes 218 that are positioned to be in alignment with the plurality of posts 140 on the bottom 104 of the lower housing 14 . The posts 140 are received in the holes 218 and, when melted by a heat staking procedure during assembly, further secure the modular base component 22 to the lower housing 14 .
As shown in FIGS. 20 and 21 , the setting/killing assembly 24 includes a horizontal axle 220 coupled to or integral with a generally rectangular loop that forms the kill bar, generally designated by reference numeral 222 , and another generally rectangular loop that forms the setting bar, generally designated by reference numeral 238 .
The kill bar 222 is formed by two spaced, generally parallel elongated arms 224 that project perpendicularly from the setting axle 220 at their base ends 226 and are joined at their opposite ends by a horizontal bar 228 that is parallel with the setting axle 220 . With the “front” side referring to that side which contacts the pest when the trap is triggered, the arms 224 and the horizontal bar 228 of the kill bar 222 preferably include a square rib 230 on a back side to increase strength, and a pointed, triangular rib 232 on the front side to increase the effectiveness of the killing aspect of the kill bar 222 (see FIG. 29 ). The setting/killing assembly 24 is preferably molded to include the setting axle 220 and the kill bar 222 as a single piece.
The setting bar 238 is preferably supported within blind central bores 236 formed in two posts 234 that protrude from the axle 220 generally perpendicularly to the kill bar loop 222 as shown in FIG. 21 . Like the kill bar 222 , the setting bar 238 has two arms 240 joined at their distal ends by a horizontal bar 242 . The arms may be press fit into the central bores 236 or, alternatively, may be molded as a single piece with the setting axle 220 and the kill bar 222 .
Located centrally on the setting axle 220 between the base ends 226 of the kill bar 222 are two spaced ridges 246 that serve to locate the bait pedal 32 laterally on the setting axle 220 . The left end, generally designated by reference numeral 248 , of the axle 220 is received in the through-going aperture 116 in the recessed area 114 of the lower housing 14 . A protruding portion 250 of the left end 248 of the axle has parallel flats 252 that engage corresponding flats 253 of the cutout 262 on the inside of the setting handle 26 (see FIG. 23 ) and an axial hole 254 to receive a fastening element, such as a screw (not shown), to secure the setting handle 26 in place during assembly.
The setting handle 26 , shown in FIGS. 22 and 23 , is preferably formed as a single piece having a curved side 256 to fit the user's thumb to facilitate pushing the handle 26 to set the trap 10 . A through-going aperture 258 is located adjacent the lower end 260 of the handle 26 and is aligned with the axial hole 254 in the setting axle 220 to receive the fastening element that secures the handle 26 to the setting axle 220 . The back of the handle, shown in FIG. 23 , has cutout 262 around the through-going aperture 258 that mates with the left end 248 of the setting axle 220 , as previously described. A further cutout 264 may be provided to reduce the weight and amount of material needed for the handle.
An upper view of the setting/killing assembly 24 in the kill position is provided in FIG. 24 . The axle 220 is received in the through-going aperture 116 in the recessed area 114 of the lower housing 14 and in the through-going aperture 258 in the handle 26 . A set spring 266 is mounted on the axle 220 between the arcuate vertical member 158 and the inner wall 268 of the recessed area 114 . One end 265 of the spring 266 is hooked over and applies force to the kill bar and the other end 267 is held in place against the bottom 104 of the lower housing 14 .
As shown in FIGS. 25 and 26 , the trip latch 172 is an elongated generally planar member having an aperture 180 adjacent a first end 182 for receiving the metal pin 170 upon which the trip latch rotates, and a tripping tip 184 at an opposite second end 186 . Projecting from the trip latch upper surface 188 is a setting hook 190 that defines a recess 192 for securing the setting bar 238 when the trap 10 is in the set position as will be described further hereinafter. In the cutaway view of FIG. 26 , the trip latch 172 is not set.
As shown in FIGS. 27A and 27B , the bait pedal 32 is preferably of a single piece construction, most preferably molded polymer, and includes a weighted end 340 and a back end 342 joined by a bridge portion 178 . The bridge portion 178 has a pair of aligned bottom cutouts 344 , 345 for snapping the bait pedal 32 onto the setting axle 220 during trap assembly, and a central cutout 346 that latches with the tripping tip 184 of the trip latch 172 when the trap is set (see FIG. 29 ). A circular cutout 331 may also be provided in the back end 342 to reduce weight and material. The bait pedal 32 rotates freely about the setting axle 220 and is located longitudinally thereon by the ribs 246 on the setting axle which, when positioned between the cutouts 344 , 345 , ensure that the bait pedal is lined up with the rest of the setting mechanism (see FIGS. 20 and 27B ).
As shown in FIG. 27B , the bottom of the bait pedal includes a projection 349 that, when the trap is assembled, is positioned over the tubular member 162 . The spring 163 , mounted within the annular channel 165 formed by tubular member 162 with central member 161 , receives the projection 349 in the center of the coils (see FIG. 26 ). Engagement of the spring 163 with the projection 349 ensures proper alignment of the bait pedal 32 and also provides upward pressure against the underside of the back end 342 when the trap is being set. With this upward pressure, the trap can be set by the user while being held in any spatial orientation.
To set the trap, the user holds the trap with one hand while pushing the setting handle 26 down over a travel range of approximately 90 degrees until the setting bar 238 locks with the trip latch 72 . This can be visualized with reference to FIGS. 21 and 24 from which shown position the setting handle is rotated clockwise toward the front wall 106 of the lower housing 14 until the trap is set as shown in FIG. 29 . This handle rotation rotates the setting axle 220 and the setting bar 238 toward the front wall 106 where the horizontal bar 242 passes over the setting hook 190 and is received in the recess 192 . With the kill bar concurrently rotated upwardly off the back end 342 of the bait pedal 32 as the setting bar is rotated, the weighted end 340 of the bait pedal causes the bait pedal to rotate on the setting axis, lowering the weighted end and allowing the back end 342 to lift off of the bottom of the lower housing. In addition, the pressure of the spring 163 against the underside of the back end 342 ensures the upward positioning of the back end, once the kill bar has been lifted, regardless of the angle at which the trap is being held during the setting process. According to a preferred embodiment, when the back end is in the “upward position”, the bait pedal is substantially parallel with the bottom of the trap.
More particularly, when the setting bar 238 contacts and presses downwardly on the setting hook 190 of the trip latch 172 , the tripping tip 184 thereof moves upwardly through the central cutout 346 . The upward positioning of the back end 342 of the bait pedal, as maintained by the pressure of the spring 163 , allows the tripping tip 184 of the latch 172 , once the setting bar has moved into recess 192 , to catch on the back edge 347 of the cutout 346 . With the trip latch 172 thus held at both ends, the setting hook 190 being tensioned upwardly by the setting bar 238 and the tripping tip 184 caught on the edge 347 preventing the second latch end 186 from moving downwardly, the trap is set.
When the trap is set, force applied by the mouse when it steps on the back end 342 rotates the bait pedal sufficiently to release the tripping tip 184 from the edge 347 of the central cutout 346 , allowing the trip latch 172 to rotate on the metal pin 170 which, due to the tension of spring 266 on the setting bar 238 , raises the setting hook 190 to release the setting bar 238 . The kill bar 222 is then free to rotate rapidly from the set position shown in FIG. 29 to the kill position shown in FIG. 24 where the horizontal bar 228 of the kill bar 222 presses downwardly under spring tension against the back end 342 of the bait pedal 32 .
Concurrently with setting of the kill bar 222 , the door assembly 28 is automatically moved to an open door position by the door opening and closing gear mechanism 30 . As shown in FIGS. 21 , 28 and 29 , the door assembly 28 includes a door 56 , the door axle 204 and a door spring 270 .
The door 56 includes a cylindrical top section 272 , a flat plate 274 , and a partial pinion gear 276 on the left end (as viewed from the front of the assembled trap) of the cylindrical section 272 . The cylindrical section 272 has an axial bore 278 through which the door axle 204 extends to enable rotation of the door 56 , and a cutout 280 to accommodate the door spring 270 through which the door axle 204 also passes (see FIGS. 21 and 29 ). Thin rings 281 are located at each end of the cylindrical section 272 for proper spacing of the door 56 between the corresponding vertically oriented planar members 194 , 196 on the modular base component 22 .
The flat plate 274 has a front surface 58 for adhesion of the rubber door seal 54 (see FIG. 8 ). The back surface 282 of the plate 274 is provided with reinforcement ribs 284 that extend in alignment with the sides of the plate and are preferably tapered from the cylindrical section 272 toward the free end 286 of the door.
The door seal 54 is adhered to the front surface 58 of the plate 274 and is preferably made of a rubber material. Other elastomeric materials that are sufficiently soft or compressible to form a good seal with the door flange 53 when subjected to the disclosed spring tension may also be used. When the trap is tripped and the door 56 is closed, the door seal 54 and the door flange 53 form a hermetically sealed trap for retaining the trapped (killed) pest and its related parasites and pathogens. As used herein, the terms “hermetically sealed” and “hermetic seal” are intended to mean a closed trap having a vacuum inside the trap enclosure, such as enclosure 16 , of between about 1.0 mmHg and about 25.9 mmHg. Stated another way, the seal can withstand a pressure of between at least 0.125 inches H 2 O to about 55.4 inches H 2 O. As known to those skilled in the art, these parameters can be measured using a leak and flow tester such as the SPRINT-LC manufactured by Uson LP of Houston, Tex.
The partial pinion gear 276 , located on the left side of the cylindrical section 272 , is configured with a plurality of teeth 288 to mesh with teeth 289 of the spur gear 302 of the door opening gear mechanism 30 . A timing mark 290 is provided on the side of the pinion gear 276 that aligns with a timing mark 292 on the door opening gear mechanism 30 (see FIG. 26 ). During assembly in the unset position, the timing marks 290 and 292 should be side-by-side, as shown in FIG. 26 . This alignment ensures that the spur gear 302 will rotate the pinion gear 276 to fully open the door 56 when the trap is set by rotating the setting handle 26 .
The door axle 204 is preferably a steel wire or rod that passes through the bore 278 of the door cylindrical section 272 and is press fit through the horizontal holes 202 in the outer and inner vertically oriented planar members 194 , 196 . The door spring 270 is a torsional spring located around the door axle 204 and in the cutout 280 in the cylindrical section 272 . One end 333 of the spring contacts and applies force to the back side 282 of the flat plate 274 of the door (see FIG. 21 ). The other end contacts and applies force against the inside of the front wall 34 of the upper housing above the door opening 50 (see FIG. 1 ).
As shown in FIGS. 30 and 31 , the door opening and closing gear mechanism 30 includes the lever arm/axle combination, generally designated by reference numeral 300 , and the spur gear 302 that works cooperatively with the partial pinion gear 276 on the door 56 . The lever arm/axle combination 300 and spur gear 302 are supported on the inner and center vertically oriented planar members 196 , 214 of the modular base component 22 .
The lever arm/axle combination 300 is preferably formed as a single piece as shown in FIG. 30 and includes a lever arm generally designated by reference numeral 294 and an axle generally designated by reference numeral 296 . The lever arm 294 has a knob 298 on the end that is engaged by right side arm 240 of the metal setting bar 238 during setting of the trap. The axle 296 has a projecting end 304 that extends through the opening 216 in the center vertically oriented planar member 214 , across the space 306 (see FIGS. 18 and 19 ) between the center and inner planar members 214 , 196 , and into the opening 206 in the inner planar member 196 where the end 304 of the axle 296 is supported on a base 308 (see FIG. 8 ). The projecting end 304 is formed to have parallel flats 310 that mate with corresponding flats 312 on the spur gear 302 as shown in FIG. 31 . The axle 296 is also preferably provided with a projection 314 that is received within a correspondingly shaped cutout 316 on one of the spur gear flats 312 to allow installation of the spur gear 302 in only one direction.
The spur gear 302 is positioned between the vertically oriented planar members 196 , 214 of the modular base component 22 and has a central opening 320 to receive the axle 296 . The flats 312 on the spur gear 292 extend into this opening 320 as shown in FIG. 31 . The spur gear 302 is properly mounted on the axle 296 when the axle projection 314 is received within the spur gear cutout 320 . Preferably, a small raised round feature 330 is formed on the axle flats 310 to help lock the spur gear 302 in place. As noted earlier, the spur gear 302 also includes a timing mark 292 that aligns in the unset position with the timing mark 290 on the partial pinion gear 276 of the door 56 during assembly. The position of the lever arm/axle combination 300 when assembled with the trap in a set condition is shown in FIG. 32 .
As shown, with the setting of the kill bar 222 , the setting bar 238 contacts the knob 298 on the end of the lever arm/axle combination 300 , pushing the knob 298 downwardly. As the knob 298 moves downwardly, the lever arm/axle combination 300 and the spur gear 302 coupled thereto are rotated counterclockwise. The spur gear 302 , in turn, rotates the pinion gear 276 on the door 56 clockwise to open the door.
With the door open and the setting bar 238 held in the recess 192 of the trip latch 172 , a mouse can enter the trap 10 through the door opening 50 . Drawn by the smell of the bait and guided by the dividing walls 66 , 68 , the mouse approaches the back end 342 of the bait pedal 32 . When the mouse steps on the bait pedal and moves the back end downwardly, the tripping tip 184 is released from the bait pedal cutout 346 and the setting hook 190 releases the setting bar 238 . The kill bar and setting bar rotate together with the setting axle under the force of the loaded set spring 266 to move rapidly to the kill position. Upon rotation of the setting bar, the knob 298 of the lever arm 294 is released and is free to move upwardly. The release allows the lever arm and axle combination 300 and the spur gear 302 to counter-rotate (in a clockwise direction). The force of the tensioned door spring 270 then actuates to close the door 56 while, at the same time, rotating the pinion gear 276 counter-clockwise which, in turn, rotates the spur gear 302 . As the door 56 closes under the force of spring 270 , the rubber seal 54 on the outside of the door mates with the door flange 53 on the inner wall of the housing to hermetically seal the enclosure 16 . The mouse, now dead, is enclosed within the housing along with any parasites and pathogens associated therewith. The trap can then be safely disposed of without exposing the user to any contact with the carcass and any pathogens associated therewith.
The trap as described herein is both humane, killing the mouse in typically less than 30 seconds, and safe for both persons and pets around the trap. The trap can be baited and set from outside the enclosure, although during testing it has been found that baiting is not necessary as mice are naturally curious about small dark spaces such as that created by the housing. The user never has to see the dead mouse, and the trap securely contains all bacteria, parasites, urine, feces, etc., associated with the mouse indefinitely, making the trap suitable for use in locations that may not be convenient for regular servicing.
While the killing mechanism described herein is a snap-trap, the present invention may also be modified to include one of several other alternative killing/incapacitating mechanisms known in the art while retaining the hermetic sealing operation of the trap.
The foregoing descriptions and drawings should be considered as illustrative only of the principles of the invention. The invention may be configured in a variety of shapes and sizes and is not limited by the dimensions of the preferred embodiment. Numerous applications of the present invention will readily occur to those skilled in the art. Therefore, it is not desired to limit the invention to the specific examples disclosed or the exact construction and operation shown and described. Rather, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A single use, hermetically sealing mousetrap has a housing defining an enclosure that is accessible through a rotatably mounted door controlled by a spring-loaded door opening gear mechanism. Mounted to the bottom of the housing inside the enclosure is a spring-actuated setting axle/kill bar and setting bar combination that is movable between a kill position and a set position by manipulation of a setting handle positioned outside the enclosure. When the setting axle/kill bar is moved to the set position, the door opening gear mechanism causes the door to open while tensioning a torsional door spring. A trip latch and bait pedal are configured to operate together to secure the kill and setting bars in the set position, with subsequent movement of the bait pedal by a mouse serving to release the trip latch. When the trap is thereby triggered, the kill bar moves rapidly to the kill position while releasing the door opening gear mechanism. The tensioned door spring then closes the door. With the door closed, the enclosure is hermetically sealed with the dead mouse inside and the trap can be disposed of without any contact between the user and the carcass along with any parasites and pathogens associated therewith. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to and is a continuation of U.S. patent application entitled, MODULAR COUNTERFLOW FILL HANGING SYSTEM APPARATUS AND METHOD, filed Mar. 13, 2013, having a Ser. No. 61/780,542, the disclosure of which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates generally to a hanging film fill pack for use for heat exchange in a cooling tower or the like. More particularly, the present invention relates to a modular hanging fill pack design and method that is efficient and economical to assemble and install in a cooling tower.
BACKGROUND OF THE INVENTION
Industrial water cooling towers have long been used to reject heat in power generation, to provide cooling water for petrochemical processes, industrial processes or the like, and serve as a means to lower the temperature of various chemical process streams and equipment. In the case of power generation plants, the cooling tower requirements can be relatively large and it is often times the practice to fabricate increasingly larger cooling towers. Counterflow towers have been found to be especially useful in these instances because of the efficiency of the towers and the compact nature of the structure. Cooling air may be brought into heat exchange relationship with the hot water either by way of convection through use of a natural draft stack, or by means of one or more large diameter, power-driven fans.
In order to further increase the efficiency of cooling towers for industrial applications which require the use of very large towers, efforts have been made to increase the effectiveness of heat exchange between the hot water and the cooling air. The degree of direct contact of the water to be cooled with the coolant air has a significant bearing on the efficiency of the cooling process. Counterflow towers, wherein the hot water and air are brought into countercurrent flow relationship have long been known to be efficient heat transfer units. Initial egg crate or slat splash bar towers were ultimately supplanted by film fill towers because of the greater heat transfer properties of a water film as compared with the multiplicity of droplets of water which are produced by splash fills. Furthermore, film fills are typically significantly shorter than splash fills thus decreasing the head on the pump delivering hot water to the tower and making operating less expensive because of the lower horsepower pump requirements.
The superior heat transfer characteristics of counterflow towers as well as improved efficiency based on lower pump heads has increased their desired use in industrial applications. Cooling tower designers in seeking to increase the efficiency of counterflow towers have also sought to further decrease the overall height of such towers by making the fill more effective than has been the case in the past. With the advent of synthetic resin sheets which are capable of withstanding higher temperatures without significant deformation than was previously the case, along with the development of resin formulations which are more resistant to deterioration under constant wet conditions, fill assemblies made up of sheets of the plastic for film flow of water thereover have in many instances completely supplanted prior fill structures which primarily relied upon break-up of the water for surface increase purposes instead of thin films of water over a large multiplicity of closely spaced sheets of plastic.
Although film fills have found acceptance in many applications including large industrial cooling towers for power generating plants and the like, problems have arisen by virtue of the fact that governmental regulatory agencies have imposed stricter limitations on the addition of agents to the cooling water which suppress growth of microorganisms and the like. For example, it has long been the practice to add chlorine or chlorine containing compounds to the cooling water in order to prevent microorganism growth. However, it is now known that when chlorine in high concentrations is discharged into streams or other natural bodies of water, the chlorine can produce adverse consequences which are harmful to biological life in the stream and in general increase what some deem to be undesirable pollution of the flowing water.
Cooling tower operators have routinely removed a portion of the cooling tower water in the form of blow down and returned it to the source such as a stream to prevent buildup of chemical additives in the water. As much as 10% of the water may be continuously returned to the stream or other water source as blow down. This water can contain a relatively high concentration of the additive and therefore significant amounts of chlorine, for example, may be present at the outlet of the cooling tower which discharges into the adjacent stream, lagoon, or lake water source. Concern over stream and water body pollution has led governmental authorities to restrict the use of additives such as chlorine in cooling tower water for preventing growth of microorganisms in the recirculating cooling water. In fact, absent a more acceptable anti-microbial additive than chlorine and which is available at a reasonable cost, many tower operators have elected to simply eliminate or drastically reduce the additives such as chlorine in the cooling tower water.
The result of the above discussed regulations is the build up of microorganism growth in the flow assembly of counterflow industrial water cooling towers. One highly effective and efficient fill assembly for counterflow towers employs corrugated plastic sheets, however microorganisms can proliferate in such fills. As the water to be cooled flows downwardly through the corrugated fill structure, microorganisms present in the water and whose growth is no longer inhibited by suitable anti-microbial compounds in the water, collect at the points of intersection of the corrugations of the fill. The microorganisms then start to multiply at the nodal points in the fill assembly. This growth can continue until complete blockage of the water flow paths through the fill unit occurs.
In like manner, unless the cooling tower water is continuously filtered, suspended solids in the make-up water from the stream or other natural water source can collect and accumulate in the water. These solids are trapped by the microorganism growths in the fill assembly and increase blockage of the water flow paths. In addition, airborne solids can build up in the water during tower operation unless the water is filtered.
The significance of the problem is apparent when it is recognized that in the case of a 500 megawatt power plant, if the plant must be shut down because of blockage of the fill assembly of the cooling tower serving such plant, the loss of revenue to the utility is many thousands of dollars per day. Replacement of the fill can take from one to two months. Thus, lost revenues readily mount to eight figure numbers.
The enormity of the problem is further demonstrated by the fact that cooling towers of the type discussed and especially those used for high-megawatt plants such a nuclear facilities, have fill assemblies whose plan area can be anywhere from one to four acres. Moreover, oftentimes the cooling towers of the type discussed employ hanging fill systems which consist of wire and tube arrangements suspended from pins or bolting systems. These current systems are very labor intensive, requiring a large amount of field labor to assemble the fill racks and to hang the fill individually from the pins in the tower. Thus, to replace such fill can very labor intensive to remove the current fill and replace it with new fill.
Accordingly, it is desirable to provide a counter-flow hanging fill design and system that is economical and efficient to install in a cooling tower. More specifically, it is desirable to provide a modular counterflow hanging fill system that provides preassembled fill modules that are easily and efficiently installed in a cooling tower or the like, reducing the labor efforts to assemble the same, and accordingly reducing assembly costs along with reducing down time of the cooling tower when replacing said fill.
SUMMARY OF THE INVENTION
In one embodiment of the present invention, a heat exchange media fill block is provided, comprising: a first heat exchange fill pack; a second heat exchange fill pack; a stake, wherein said stake pierces said first fill module and extends through said first heat exchange fill pack to pierce said second heat exchange fill pack to prevent the first and second heat exchange fill packs from shifting with respect to one another.
In one embodiment of the present invention, a heat exchange media fill block is provided, comprising: a first heat exchange fill pack; a base frame that supports said first heat exchange fill pack; a stake, wherein said stake pierces said first heat exchange fill pack and extends through said first heat exchange fill pack wherein said stake is received by said base frame.
In another embodiment of the present invention, a hanging fill support bracket for use in a cooling tower of the like is provided, comprising: a first side having a first upper portion and a first lower portion; a second side opposing said first side that has a second upper portion and a second lower portion; a top connect to said first and second sides that extends between said first and second upper portions; and a shaft having a first and second end that extends between the first lower portion and the second lower portion, wherein said shaft is retained by each said first and second lower portion.
In another embodiment of the present invention, a heat exchange fill apparatus for use with a cooling tower is provided, comprising: a support frame assembly; a media fill block, comprising: a first heat exchange fill pack; a second heat exchange fill pack; and a stake, wherein said stake pierces said first heat exchange fill pack and extends through said first heat exchange fill pack to pierce said second heat exchange fill pack to prevent the first and second heat exchange fill packs from shifting with respect to one another; a base frame that supports said first heat exchange fill pack and said second heat exchange fill pack; at least one cable that extends through the media fill block, wherein said at least one cable is connected to said base frame; wherein said stake extends at least partially through said first and second heat exchange fill packs and is received by the base frame; a hanging fill support bracket that attaches to said support frame assembly, said support bracket comprising: a first side having a first upper portion and a first lower portion; a second side opposing said first side that has a second upper portion and a second lower portion; a top connect to said first and second sides that extends between said first and second upper portions; and a shaft having a first and second end that extends between the first lower portion and the second lower portion, wherein said shaft is retained by each said first and second lower portion, wherein said at least one cable is connected to said hanging fill support bracket.
In yet another embodiment of the present invention, a method for assembling a fill pack for use in a cooling tower is provided, comprising the steps of: placing a first fill pack on a base; placing a second fill pack adjacent said first fill pack on the base; inserting a stake through said first fill pack; optionally inserting the stake through said second fill pack; engaging the base with said stake to retain the first fill pack and optionally the second fill pack.
In still another embodiment of the present invention, a method for conducting heat exchange using a cooling tower is provided, comprising: passing a fluid to be cooled a fill block comprising: a first heat exchange fill pack; a second heat exchange fill pack; a stake, wherein said stake pierces said first fill pack and extends through said first heat exchange fill pack to a base to prevent the first heat exchange fill pack from shifting; and generating an air current; and passing the air current over the fill block.
In another embodiment of the present invention, a heat exchange fill pack for use in a cooling tower is provided, comprising: means for placing a first fill pack on a base; means for placing a second fill pack adjacent said first fill pack on the base; means for inserting a stake through said first fill pack; optional means for inserting the stake through said second fill pack; means for engaging the base with said stake to retain the first fill pack and the second fill pack.
In another embodiment of the present invention, a beam bracket for use with a cooling tower is provided, comprising: a first halve having a first top portion, a second side wall and a first sloped portion; a second halve having a second top portion, a second side wall and a second sloped portion, wherein said second halve engages said first halve; a first bolt that engages said first top portion to said second top portion.
There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of hanging fill system in accordance with an embodiment of the present invention.
FIG. 2 is a detailed perspective view of the hanging fill system illustrated in FIG. 1 .
FIG. 3 is a detailed view of a connection point of the hanging fill system in accordance with an embodiment of the present invention.
FIG. 4 is another detailed perspective view of the hanging fill system illustrated in FIG. 1 .
FIG. 5 is a partial schematic view of the fill support system in accordance with an embodiment of the present invention.
FIG. 6 is a detailed view of the fill support system illustrated in FIG. 5 .
FIG. 7 is another detailed view of the fill support system depicted in FIGS. 5 and 6 .
FIG. 8 is a schematic view of a bracket apparatus in accordance with another embodiment of the present invention.
FIG. 9 is a schematic side view of the bracket apparatus depicted in FIG. 8 .
DETAILED DESCRIPTION
An embodiment of the present inventive system for a modular hanging fill system, generally designated 10 is illustrated. Turning specifically to FIG. 1 , a modular hanging fill system 10 is illustrated having a modular fill block 12 that is comprised of multiple fill packs 22 and 24 that form the fill block 12 . The modular hanging fill system 10 includes a series of longitudinal beams 14 and 16 having cross beams 18 extending there between from which the fill block 12 hangs. The longitudinal beams and cross beams combine to form a grid like structure from which the fill block 12 hangs. The longitudinal 14 , 16 and cross beams are support by a series of columns 20 . The modular fill block 12 is supported by a series of fill supports 50 (that will be discussed in further detail below) that comprises an upper latching portion 52 that connects to the cross beams 18 and a lower base portion 53 upon which the fill block 12 sits.
Turning now to FIG. 2 , a detailed view of the bottom portion 53 of the fill support is illustrated in more detail. The bottom portion 53 comprises transverse support beams 26 (one pictured) with longitudinal beams 28 extending there between. The fill support 50 , also includes cable 32 that extends from the upper portion 52 to the transverse support beam where it attaches at an attachment port 36 . FIG. 2 further illustrates a stake 34 that extends through the fill block 12 (shown transparent for clarity) where it engages a receiving portion 37 via its slot 38 . The receiving portion 37 extends from the cross beam 28 . The stake 34 may be any conduit or rod that extends through said fill block 12 . While the stake 34 is depicted in a vertical orientation or normal position, to the bottom portion 53 , the stake 34 may alternatively be oriented at an angle or sloped orientation. For example, the stake 34 may extend within a flute of cross-corrugated fill or the like.
Turning now to FIG. 3 , a detailed end view of the transverse beam 26 is illustrated showing the support cable 32 engaging the side beam 26 . As illustrated, in one embodiment of the present invention, the support cable 32 extends through the port 36 of the side beam 26 and engages and is connected to the said beam 26 via a bolt and loop connection. The aforementioned bolt and loop connection includes a loop 40 at the end of the support cable 32 that encircles a bolt 42 that extends within the interior of the beam 26 . The bolt 42 may be secured to the beam 26 via a washer 44 and nut 45 connection. The bolt 42 may be replaced by a pin. Alternatively, the bolt or pin may be secured by a mechanical attachment means, for example, weld, push caps, cotter pins or screw connection.
Turning now to FIG. 4 , another detailed end view of the bottom portion 53 of the support system is depicted. As illustrated in FIG. 4 , the receiving portion 37 and the slot 38 are illustrated having the stake 34 inserted therein. FIG. 4 also depicts a bracket 46 that functions to support transverse beam 26 . FIG. 4 further illustrates in detail the receiving portion 37 having the slot 38 wherein the stake 34 is inserted therein in combination with the cable 32 extending to engage the support beam 26 .
Turning now to FIGS. 5 and 6 , the fill support system, generally designated 50 , is illustrated having the previously described latching portion 52 and the previously described base portion 53 . Whereas FIG. 5 schematically depicts the fill support system 50 without the fill having the upper and lower portions, FIG. 6 is a detailed illustration of the latching portion 52 .
The latching portion 52 comprises a shaft 54 that extends between a pair of side struts 58 . The side struts 58 are connected via a top portion 60 . In one embodiment of the present invention, the side struts 58 may comprise two components, an upper portion that engages the top 60 and a lower portion 59 through which the shaft 54 extends. Alternatively, the latching portion may be a single, integral piece if desired. As illustrated in FIG. 6 , one embodiment of the present invention utilizes a cotter pin 62 or the like that retains the shaft 54 between the struts 58 . In one embodiment of the present invention, a cotter pin 62 may be used on both ends of the shaft 54 whereas other embodiments may employ only a single cotter pin 62 . Alternatively, the shaft 54 may be retained via a compression fit or any other mechanical means or method.
As depicted in FIG. 6 , and more specifically in FIG. 7 , the cable 32 connects or is attached to the latching portion 52 via the shaft 54 by way of an attachment loop 56 . Turning specifically to FIG. 7 , the attachment loop 56 has an upper curved section 64 that extends between first and second sides 66 . The first and second sides 66 extend generally parallel to one another in opposing relationship. The attachment loop 56 further includes a base that is comprised of an first flap 68 and a second flap 69 . As illustrated in one embodiment of the present invention, flap 68 and flap 69 overlap one another to form the base of the attachment loop 56 . Alternatively, in another embodiment, the base may be a solid piece and not comprise separate flaps as shown.
The cable 32 extends through the flaps 68 and 69 wherein the end 70 extends into the loop 56 . The end 70 may be threaded wherein it engages a washer 72 and nut 73 on one side of the flaps 68 , 69 and another nut 74 and washer 75 on the other side of the flaps 68 , 69 . The cable 32 may be alternatively be connected or attached to the loop 56 by any preferred attachment means or method.
During operation, the fill block 12 is comprised of multiple individual fill packs. These individual fill packs are assembled at the factory wherein the stake 34 or multiple stakes is inserted through said packs as previously discussed. The stakes 34 may be constructed of any material, for example, polyvinyl chloride (PVC) or any other preferred plastic or alternative material. The stakes 34 extend through “normal” internal paths of the fill packs and function to prevent the fill modules from shifting or losing their shape during transportation and assembly. The stakes 34 also function to lock or anchor the fill pack(s), and thus the fill block 12 , to the base frame 53 . Also, in one embodiment of the present invention, the various cables 32 that support the fill media may be inserted prior to shipping the fill block 12 if desired.
Upon the fill packs 12 arriving at the installation site, for those embodiments shipped with the cables installed, the cables are attached to the base portion 53 and to the beam 26 . The cable 32 is next attached to the upper portion 52 of the fill support system 50 . During the installation process, the upper portions 52 of the fill support system 50 are typically hung from a beam or the like, similar to that illustrated in FIG. 1 , prior to the fill pack installation in the tower. The aforementioned beam is typically part of an overall, larger frame structure or the support assembly of the cooling tower. As previously described, the cable 32 engages and is attached to the upper portion 52 via the loop 56 and shaft 54 . Alternatively, the cable may be inserted through the fill media packs 12 are attached to the base portion 53 and to the beam 26 at the site. The cable 32 is then connected to the upper portion 52 of the fill support system 50 . As in the embodiment described above, the cable 32 engages and is attached to the upper portion 52 via the loop 56 and shaft 54 .
In this position fill block 12 maybe secured to the base 53 as needed however as illustrated in FIGS. 2 and 4 , the stakes also assist to secure the fill packs 12 by engaging the receiving portion 37 and inserted through the slots 38 . The stake's 34 engagement with the slot 38 helps to secure the fill block 12 to the base 53 of the fill support system 50 .
The above-described process is repeated as necessary depending upon the size of the respective cooling tower in which the fill packs 12 are employed. Moreover, the above-described fill system allows for the fill to be efficiently installed and replaced due to the ability to assemble the fill packs at the manufacturing plant and ship in the pre-assembled state. Once arriving at the cooling tower site, the individual packs are efficiently installed in the manner described above.
Turning now to FIG. 8 and FIG. 9 , an alternative embodiment of the present invention is depicted, wherein a beam bracket generally designated 200 is illustrated. The beam bracket comprises two sides or halves 202 and 204 that encircle the support beam 206 from which the fill block (not pictured) suspends. As illustrated in FIG. 8 , the halves 202 and 204 are retained or attached to one another via an upper or top bolt 206 and a bottom or lower bolt 208 . The upper bolt 206 extends through first and second top flanges 210 and 212 each corresponding to a halve 202 , 204 . Similarly, the lower bolt 208 extends through first and second lower flanges 214 and 216 each corresponding to a halve 202 , 204 .
As depicted in FIG. 8 , each halve comprises a top portion 218 and 220 , opposing side walls 222 and 224 and sloped bottom portions 226 and 228 . As illustrated, the sloped portions 226 , 228 extend from each respective side wall 222 , 224 to each respective flange 214 , 216 through which the bolt 208 extends as previously described. In the embodiment illustrated, the bolt 208 may be rotated to collapse or pull together the sloped portions 226 , 228 changing the angle of said sloped portions 226 , 228 as indicated by FIG. 8 . Alternatively, the bolt 208 may be rotated in the opposite direction, “loosening” the angle of the sloped portions 226 , 228 . The aforementioned collapsing and releasing of the of the sloped portions 226 , 228 via the bolt 208 may be used to adjust the height of the fill block by moving the cable upward or downward depending upon the angle of the sloped portions 226 , 228 .
Continuing to refer to both FIGS. 8 and 9 , the lower flanges 214 , 216 , include a series of holes or bores 232 that allow for the cable 230 to be attached at various heights via a bolt 234 . The above-described holes or bores 232 allow for the fill block to be adjusted in terms of hanging height.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A heat exchange fill apparatus for use with a cooling tower that employs a support frame assembly. The heat exchange fill apparatus has a media fill pack that includes a of fill pack media modules wherein a stake, prevents the modules from shifting with respect to one another. The modules are installed in a cooling tower of the like via a hanging fill support. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is related generally to nuclear reactors and in particular to radiation shields for space nuclear reactors.
2. General Background
In nuclear reactors, a reflector is generally placed around the core to reduce neutron leakage from the core and massive shields are utilized to protect critical areas from ionizing radiation dangerous to personnel or damaging to sensitive equipment.
Particularly in nuclear reactors designed for use in space applications, the size and mass is severely limited by mission requirements, launch vehicle limitations, and the cost of placing massive components into orbit and then assembling them into operating systems. For a small power reactor of about 100 KWe the required shield mass is about 25% of the reactor mass on an unmanned station. On manned stations or for reactors of greater power the relative mass of the shield is greater and then may become the limiting component.
Typical space reactor designs use radiation "Shadow" shields external to the reactor containment with the heat developed in the shield being dissipated by thermal radiation from the surface. The problems of neutron and gamma ray shielding are typically dealt with separately by the use of lithium hydride as the neutron shield and tungsten metal as the gamma ray shield. It can be seen from the above that there is a need for compact shield designs that minimize the overall system mass.
SUMMARY OF THE INVENTION
The invention solves the aforementioned problem in a straightforward manner for gas cooled space power and propulsion reactors. What is provided is an integral reactor vessel head and radiation shadow shield. The radiation shield is comprised of a primary shield designed to fully satisfy the gamma ray attenuation requirement and substantially satisfy the neutron attenuation requirement, and a secondary shield designed to satisfy the residual neutron attenuation requirement. The primary shield consists of a porous packed bed of small spheres of a metal hydride, preferably zirconium hydride. The secondary shield is comprised of a similar bed of borohydride spheres, preferably lithium borohydride. Heat deposited in the two regions by neutron and gamma ray attenuation is recovered by the reactor coolant flow and contributes to useful power output of the reactor.
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature and objects of the present invention, reference should be had to the following description, taken in conjunction with the accompanying drawings, in which like parts are given like reference numerals and, wherein:
FIG. 1 is a schematic view of an open cycle space power reactor system.
FIG. 2 is a partial cutaway view of the reactor and shield.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, it is seen in FIG. 1 that a typical open cycle space power reactor system is generally comprised of reactor 10, alternator 12, turbine 14, pump 16, coolant tank 18, recuperator 20, and vent 22. Coolant flows through lines 23 to the various elements of the system to generate power in a manner known in the industry. The reactor is positioned and oriented so that the shield is most effective in reducing radiation levels in manned compartments or other critical areas.
The present invention, generally designated by the numeral 24 in FIG. 2, provides for a modification of reactor 10. In addition to the normal radial reflector Il and axial reflector 28 around core 13, shield 24 is provided in integral reactor vessel head 26, which is sized to receive shield 24. Shield 24 is generally separated into two separate regions containing materials which act synergistically with the axial reflector 28 to reduce the leakage of neutrons from the core and to limit gamma ray and neutron radiation levels in vital areas of the space vehicle. Beryllium or beryllium alloys or compounds are preferred for the axial reflector because of their favorable neutron scattering properties and their relatively low density.
As seen in FIG. 2, the axial reflector material 30 is provided with channels 32 for coolant flow. Core grid plate 38 is provided with apertures 40 which distribute coolant flow into the reactor core.
Primary shield region 42, adjacent to and upstream of axial reflector 28, contains gamma ray and neutron attenuation material 44 preferably in the form of a packed bed of small spheres of a size range which allows adequate passages for coolant and an acceptable pressure drop through the system. Although previously proposed gamma radiation shields have specified a dense high atomic number metal such as tungsten in a separate region, the synergy of the invention is best accomplished by a medium atomic number metal hydride having the lowest possible neutron absorption cross section and serving multiple functions. This permits the downstream side of primary region 42 to supplement the reflecting function of axial reflector 28. Zirconium hydride is the preferred material to be used in this region. The zirconium component is primarily effective in gamma ray attenuation and the hydrogen component is primarily effective in neutron attenuation. The reflecting function of axial reflector 28 may also be further enhanced by the optional use of a metal deuteride in place of the corresponding metal hydride (zirconium deuteride in place of zirconium hydride) in a subregion 46 of primary region 42 adjacent region 28. Mixing of the deuteride and hydride materials is minimized by the constraint of thick rigid screens on either side of primary region 42. However, an optional screen 48 may be positioned between the deuteride and hydride layers if it is desired. The thickness of the optional deuteride layer will depend on overall system design requirements but ordinarily will comprise only a relatively small portion of the total thickness of primary region 42. The primary function of region 42 is to attenuate gamma rays and the thickness of this region is chosen to fully accomplish this function. Due to the small neutron absorption cross section of the preferred metal, the production of secondary gamma rays by neutron capture and by the subsequent decay of activated elements is minimized. Neutron attenuation is also a major function which is accomplished by the high hydrogen concentration in primary shield region 42. In some cases the full neutron attenuation required by the primary shield may be satisfied by primary region 42 alone when its thickness is sufficient to satisfy the gamma ray attenuation requirement. In such cases, secondary shield region 50 may be omitted and integral reactor vessel head 26 shortened accordingly.
Rigid screen 52 separates primary region 42 from secondary region 50 while rigid screen 54 holds the material of secondary region 50 in position. Secondary region 50 contains neutron attenuation material 56 in the form of a packed bed of small spheres of a light-metal borohydride as in primary region 42. The preferred material for this region is lithium borohydride because of its very high hydrogen atom density per unit mass of the bulk material. The lithium and boron may also be enriched in the isotopes 6 Li and 10 B respectively for increased effectiveness.
Rigid screens 36, 52, and 54 are preferably formed from beryllium because of its high neutron scattering cross section and low neutron absorption cross section. Rigid screen 36 prevents the material in primary region 42 from entering channels 32 in axial reflector 28.
In operation, coolant flows through inlet nozzle 58 into reactor plenum 60 and respectively through regions 50, 42, and 28 as indicated by the arrows. The three regions return heat deposited therein to the coolant as it flows toward core 13 and then out reactor 10 as indicated in FIG. 1 to generate useful energy in a known manner. The two regions 42 and 50 provide for gamma ray and neutron attenuation as well as eliminating the need for a separate heat rejection system. This results in the ability to reduce the size and mass of the reactor radiation shields.
Alternative materials may also be used in the two shield regions. Hydrides of other suitable metals such as yttrium and titanium may be used as all or part of the material in primary region 42. Lithium hydride or hydrides or borohydrides of beryllium or other suitable metals may be used as all or part of the material in secondary region 50. Also, solid compacts with formed cooling channels may be used in place of the packed beds of regions 42 and 50. Vessel head 26 may also be tapered and of a larger diameter in regions 42 and 50 to provide a wider shielded zone if required.
Because many varying and differing embodiments may be made within the scope of the inventive concept herein taught and because many modifications may be made in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. | A shield for a gas cooled nuclear reactor. The reactor vessel head is provided with two regions of material which act in synergism to reflect neutrons back to the core, attenuate gamma rays and neutrons, and allow heat recovery. The primary region attenuates gamma rays and provides significant neutron attenuation. The secondary region provides the residual neutron attenuation. | 6 |
CROSS-REFERENCES TO RELATED APPLICATIONS
The present application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) to currently pending Australian Patent Application No. 2013201234 filed 4 Mar. 2013 entitled WETTING OF EVAPORATIVE COOLER PADS, which claims priority to currently pending Australian Provisional Patent Application No. 2012900922 entitled WETTING OF EVAPORATIVE COOLER PADS filed Mar. 8, 2012. The present application claims priority the above-identified patent applications, which are incorporated in their entireties herein by reference for all purposes.
FIELD OF THE INVENTION
This invention relates to evaporative air coolers used for the comfort cooling of building space. In particular, the invention relates to method and means for wetting evaporative pads of evaporative coolers and the provision of evaporative coolers in a more compact configuration.
DESCRIPTION OF THE PRIOR ART
Throughout this description and the claims which follow, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps.
The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in Australia.
An evaporative air cooler essentially comprises a fan, evaporative pads, a pump, water distribution means and a cabinet to contain these components which also incorporates a water reservoir. The evaporative pads are kept wet by pumping water from the water reservoir via a water distribution system. In operation outside air is drawn through these wetted evaporative pads and is cooled by the evaporation of water from within the evaporative pads. The cooled air then passes through the fan to ducting for distributing air to the space to be kept cool.
The evaporative pads are made from a media which is easily wetted while allowing air to pass through the media and interacting with the wetted surfaces within the media. The evaporative media has the characteristics of high internal surface area, good retention of water, good wicking characteristics and structural integrity. Traditionally, shredded wood wool contained within an open frame has been used as an evaporative medium. More recently, manufactured media made from resin impregnated corrugated paper has become almost universally popular. The corrugated paper media has all the desired characteristics as well as its own structural integrity when formed into an evaporative pad without necessarily requiring it to be contained in a frame.
Traditionally the evaporative media has been kept continually wetted while the evaporative cooler is in operation. This requires water to flow continuously through the media. A percentage of the water flow is evaporated into the airstream passing through the media, generally orthogonal to the direction of water flow while any water not evaporated runs out of the bottom of the media and returns to the water reservoir. The rate of evaporation of water is determined by the psychrometric properties of the air entering the evaporative pads and the rate of air flow. The total water flow rate circulating through the pads is determined by the characteristics of the pump and water distribution means.
All types of evaporative media pads have a limiting velocity of air flow which can be passed through the media without undesirable consequences. A most important consequence to be avoided is for free water within the media to detach and become entrained in the air flow stream as droplets. This tendency to detach is determined by the type of media, the rate of water flow in excess of that required for evaporation and the velocity of air through the media. Consequences of water inclusion in the delivered air stream include wetting and leaking from ductwork, accelerated corrosion of ducting and accumulation of salt deposits (from salts dissolved in the water) inside the conditioned space.
The water flow rate in excess of evaporation is determined at the design stage. It must be sufficient to ensure complete wetting of the evaporative media under the most adverse weather conditions, and enough to ensure dirt and salt deposits within the media are flushed to the reservoir. In practice, the water flow rate is usually set between 5 and 10 times the evaporation rate under design conditions. This ensures there is still sufficient excess water under the most adverse weather conditions.
With water flow rates within the usual limits, the limiting air velocity through the evaporative media pads has been found by experiment to be about 2.5 m/s for corrugated paper media and a little higher at around 3 msec for wood wool media.
The design of evaporative coolers is based on these limitations of airflow velocity through evaporative pads. The area of evaporative pad required is determined by the design total air delivery rate of an evaporative cooler, divided by the allowable air flow velocity. This determines the fundamental dimensions of an evaporative cooler, setting the boundaries for the balance of a cooler design.
It would be commercially advantageous if the allowable airflow through the evaporative media could be increased. This would allow reduction of the area of evaporative pad required to achieve the design performance and a more compact overall design could be possible. A side benefit could be an evaporative cooler with a lower height thereby reducing the aesthetic intrusion of the cooler on the roofline of the building. An overall smaller evaporative cooler for equivalent total airflow delivery will have obvious advantages in manufacturing cost.
The air velocity through the evaporative media could be increased considerably if the media was intermittently wetted but had no additional water flow through it during most of its operation. Under these circumstances, there would be no free water on the surfaces within the evaporative media and therefore no tendency for water to become entrained in the airflow across the surfaces. There will remain a requirement that all surfaces within the evaporative media always remain wet. This requirement can be met by constructing the media from material which can retain substantial volumes of water within itself through a porous characteristic, and with the capacity to readily distribute water to all surfaces through internal wicking. Typically, the corrugated paper media currently available satisfies these requirements.
SUMMARY OF THE INVENTION
In a first aspect the present invention provides a method of controlling the operation of an evaporative air cooler, said method comprising intermittently wetting an evaporative pad of the cooler with an amount of water in excess of the capacity of the pad to absorb and retain during each wetting operation of the pad, varying the airflow through the pad during the intermittent wetting to a velocity so as to not entrain substantial quantities of water in the airflow during the wetting, and increasing the velocity of the airflow through the pad after each intermittent wetting so as to raise the level of cooling output of the cooler between each intermittent wetting.
An embodiment of the first aspect operates by reducing the airflow speed through a pad before a wetting is commenced and delaying increasing the airflow speed until a predetermined period after wetting has ceased.
Preferably, the method of this invention is applied to an evaporative cooler comprising a plurality of separate evaporative pad sets and wherein each pad set includes an associated separately controllable fan for varying the airflow there through.
In another aspect the present invention provides a control system for an evaporative cooler for controlling the velocity of airflow through evaporative pads of the cooler in association with intermittent wetting of the pads with quantities of water in excess of the capacity of the pads to absorb and retain during the wetting, said control system determining the velocity of airflow through the pads and being adapted to vary that velocity in dependence upon a period of wetting of the pads and another period of operation of the cooler apart from each period of wetting.
In a preferred embodiment the control system employs a static pressure transducer downstream of the airflow through each pad whereby a pressure differential between each respective downstream transducer and ambient atmospheric pressure provides a measure of the airflow velocity through the pad.
In a further preferred embodiment the control system employs static pressure transducers upstream and downstream of the airflow through each pad whereby a pressure differential between each respective upstream and downstream transducer provides a measure of the airflow velocity through the pad.
Still further embodiments of the control system employ a hot wire or rotating vane anemometer in the downstream airflow from each pad to provide a measure of the velocity of the airflow through the pad.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described by way of example with reference to the accompanying drawings, in which:
FIG. 1 schematically shows a typical prior art evaporative air cooler with its component parts;
FIG. 2 shows a section through an evaporative pad of the cooler of FIG. 1 illustrating water entrainment in the airflow;
FIG. 3 is a section view similar to FIG. 2 showing controlled water circulation and differential pressure monitoring across the evaporative pad in accordance with an embodiment of the present invention; and
FIG. 4 shows a multi-fan evaporative cooler adapted to operate in accordance with the present invention
DESCRIPTION OF EMBODIMENTS
In a typical prior art evaporative air cooler of FIG. 1 , water from reservoir 8 is moved by pump 6 to water distribution system 4 which distributes water to the top of evaporative pads 2 . Water travels through the evaporative pads 2 under gravity with excess water 14 returning from the underside of pads 2 to reservoir 8 .
A fan 10 draws air 20 into the evaporative pads 2 thereby cooling the air by evaporation. After passing through the evaporative pads 2 and then fan 10 , cooled air 22 is delivered to the ducting 24 for distribution to a conditioned space.
The combination of total air delivery (cooled air 22 ) and the total face area of evaporative pads 2 subjected to incoming air 20 determines the velocity of air entering the evaporative media of evaporative pads 2 .
FIG. 2 schematically shows the effects of an evaporative pad when subjected to excess water. Water droplets from within the evaporative media can be entrained in the air flow as it passes through the evaporative pad. Water 30 from water distribution system 4 is distributed to the top of evaporative pad 2 . As this water flows down through evaporative pad 2 in a generally vertical direction under gravity, air flow 20 (which will be hot dry air under normal operating conditions) enters the evaporative pad orthogonal to the water flow down through the pad. As the air flows through the pad, a proportion of the water wetting the internal surfaces of the evaporative pad will evaporate into the air flow. This evaporation will cool the internal surfaces of the pad media, which will then cool the temperature of the air flowing through the pad. Air flow 32 exiting the evaporative pad will therefore be cooler and have a higher humidity than the airflow 20 entering the evaporative pad. The rate of evaporation is dependent on the psychrometric properties of the air 20 entering the pad and the velocity of air flow 20 .
Any water flowing through the evaporative pad in excess of the evaporation rate into the airflow passing through leaves the evaporative pad from the bottom and is returned to reservoir 8 . This excess water is depicted as water 34 in FIG. 2 .
This water in excess of evaporation requirements means that there will always be free water on the internal surfaces of the evaporative media. If the airflow across this free surface water is high enough, water will be displaced from the surfaces and become entrained in the airflow leaving the evaporative pad. The entrained water is shown as droplets 36 in FIG. 2 . Entrained water in the airflow of an evaporative cooler is an undesirable condition. The airflow required to cause free surface water within the evaporative media to become entrained in the airflow is dependent on the degree of excess water available and the velocity of air entering the evaporative pad.
An embodiment of the present invention in FIG. 3 incorporates a control system with inputs from static pressure transducer 40 located on a side of the evaporative pad external to the evaporative cooler, and a static pressure transducer 42 located on the inside of the evaporative cooler downstream of the evaporative pads. The difference in outputs of transducers 40 and 42 measures the static pressure differential across the evaporative pad induced by the airflow through the pad. This static pressure differential has a direct relationship to the air velocity through the evaporative pad and correlates to a measure of that velocity.
The control system of the evaporative cooler is programmed to use this measure of air velocity to control the wetting of the evaporative pads. During a wetting sequence, the control system reduces the speed of fan 10 until the air velocity through the evaporative pad is below the velocity known to result in water entrainment in the airflow through the pad. Water is then applied via the pump and water distribution system for a period of time to achieve complete wetting of the evaporative media and the flushing of any dirt or contaminants caught in the evaporative pad back into the reservoir.
At the end of the time required for wetting, the water distribution system is turned off (generally by simply turning off the pump or switching a valve), and any free water within the evaporative media is allowed to flow back into the reservoir. At this time, the speed of fan 10 is increased resulting in an increase in the airflow through the evaporative pads. Since there is now no free water on the internal surfaces of the evaporative media, there will be no water available to be entrained in the airflow. It is found that the airflow can be increased substantially above the prior art method of operation without any significant risk of water entrainment.
When the evaporative cooler is operated without constantly flowing water, evaporation and cooling of the airflow still occurs but from water stored within the bulk of the material from which the evaporative media pads are manufactured. The evaporative media pads are manufactured from materials with the property of retaining relatively large quantities of water within the material and the property of readily wicking the stored water to all surfaces within the media. It is found from experience that the evaporative media can continue to cool and humidify the air passing through it for a considerable period of time before it is necessary to wet the pads again using the watering sequence described above.
With this method of operation, the airflow through the evaporative cooler can increased considerably over the airflow in an equivalent prior art cooler at all times except during the wetting sequence. Since the wetting sequence only requires a small percentage of the operating time (typically 10%-20%), an evaporative cooler using the method of the present invention can deliver considerably more cooled air on average than the equivalent prior art cooler. Alternatively, an evaporative cooler of equivalent capacity to prior art coolers could be designed to be considerably smaller than such prior art coolers since much less surface area of evaporative pad is required to achieve the same performance.
It will be appreciated that there are many methods by which the velocity of airflow through evaporative pads can be measured for use in controlling a cooler in accordance with the present invention. It would be possible to use only a single pressure transducer to estimate the pressure differential since the reference pressure outside of the evaporative cooler is the nominal ambient atmospheric pressure. Alternatively, the air velocity through the pads could be measured using velocity transducers such as hot wire or rotating vane anemometers. This method of control can be applied by using any means of estimating air velocity.
The maximum time between wetting sequences to ensure continuous cooling of the air delivered by the evaporative cooler will be very dependent on the psychrometric condition of the air entering the pads. This period could be shortened considerably in very hot and dry environments. In a simple control system based on the current invention, fixed timers could be used to control both the wetting sequence and the time between wetting sequences. The time intervals could be based on experimental results for the normal design weather conditions, with an index factor applied to cover the worst anticipated weather condition. Such a control would work satisfactorily in terms of continuously delivering cooled air under all weather conditions, but would be wetting the pads more frequently than necessary under milder weather conditions.
As a further refinement in another embodiment of the current invention, a transducer is added which gives a continuous measurement of the psychrometric conditions of the incoming air. Measurement of air temperature and relative humidity is sufficient to calculate all the necessary properties of the air. From these measurements, the control system is able to estimate the rate of water evaporation from the pads during operation between wetting sequences and adjust the time interval between wetting sequences accordingly. Such an arrangement would maximise the air delivery by reducing the number of wetting sequences in mild weather with consequent increases in average performance.
FIG. 4 shows a multi-fan evaporative cooler operating with a control system in accordance with an embodiment of the present invention. In operation, wetting sequences are undertaken sequentially between the evaporative pads influenced by each of the fans. The sequence begins with a first fan 51 and its immediately adjacent evaporative pads 61 . This fan 51 is reduced in speed until the velocity through the evaporative pads 61 is below the critical velocity for water entrainment as measured by transducers 55 installed to deduce that velocity. A wetting sequence is then undertaken on this evaporative pad. At the conclusion of the wetting sequence, fan 51 is returned to normal operating speed and a wetting sequence of slowing the fan and then wetting the pad is commenced for pads 62 adjacent fan 52 . This sequence is repeated until all evaporative pads have been wetted (for example, in FIG. 4 , followed by the combination of fan 53 and evaporative pads 63 ). Each fan and evaporative pad combination wetting sequence is monitored by respective pressure transducer pairs 55 , 56 , 57 . An entire wetting sequence is again commenced when the controller determines that it is time to re-commence the wetting sequences to ensure that continuously cooled air is delivered.
By application of this invention, compact, economical evaporative air coolers can be constructed which are smaller and less expensive than prior art coolers while delivering the cooling capacity of those larger prior art coolers. | A method of controlling the operation of an evaporative air cooler where the pads ( 2 ) of the cooler are intermittently wetted with an amount of water ( 14 ) in excess of the capacity of the pads ( 2 ) to absorb and retain during each wetting operation of the pad. The airflow ( 20 ) through the pads during intermittent wetting being limited to a velocity so as to not entrain water in the airflow during the wetting operation and the velocity of the airflow through the pads is increased after each intermittent wetting so as to raise the level of cooling output ( 22 ) of the cooler between each intermittent wetting operation. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to photography and, more particularly, to an anti-flare structure for use in a photographic optical system.
2. Description of the Prior Art
In photographic optical systems the objective lens will generally satisfactorily reproduce a larger conjugate object area than is desired to be recorded in the photographic emulsion. Consequently, radiation from outside of the desired field of view of the system can enter the system through the objective lens because the lens "sees" more than is necessary. Once this unwanted radiation enters the system, it can reflect off the system's internal support structure, e.g., camera walls, and eventually reach the photographic emulsion. When this occurs, depending on the nature of the internal reflections, either extraneous images are recorded in the emulsion or an overall fog results causing a reduction in the contrast of the final picture. In either case, the quality of the final picture is seriously degraded if the unwanted radiation is not prevented from reaching the emulsion during exposure.
There are fundamentally two ways of dealing with this problem. The first way is to prevent the unwanted radiation from entering the objective lens by making its field correspond to the field of view of the system. The second is to allow the unwanted radiation to enter the system and then prevent it from reaching the emulsion by absorbing it in the system or by providing an internal baffling arrangement which prevents the emulsion from seeing it. An example of the first is described in U.S. Pat. No. 3,488,103 issued Jan. 6, 1970, and entitled "Anti-Glare Improvement For Optical Imaging Systems". In this patent an external anti-glare baffle having a specularly reflective surface formed from an oblate hemispheroid is described. An aperture in an upper horizontal surface of the hemispheroid is defined by all the foci of the hemispheroid such that rays which enter the baffle through the aperture or through the foci at the edges of the aperture and impinge on the reflective surface are specularly reflected out of the baffle. A viewing aperture is provided at the centeral portion of the reflective surface for permitting passage of rays emanating from within the desired field of view. Although this arrangement is effective, it would be impractical to use it with a photographic system where size is a limitation. The more conventional solution, especially in photographic systems, e.g. cameras, is to use the second way. Included in the second category are such solutions as lining the interior of the systems with an absorbing material such as flocking, spraying the interior with a highly non-reflective flat black coating of paint, or providing a baffling arrangement. These solutions, too, are satisfactory but have limitations where the size and manufacture of the optical system are overriding concerns. For example, adding flocking material or painting are secondary manufacturing operations. Internal baffling arrangements add size as well as additional manufacturing steps, but can be quite effective, as, for example, their application in Polaroid Corporation's Square Shooter 2 Land Cameras where they are used in combination with specularly reflective light traps running perpendicular to the optical axis of the camera. Therefore, a solution is required which will permit the simplified manufacture of a minimum sized photographic optical system that will effectively deal with unwanted radiation outside its field of view.
SUMMARY OF THE INVENTION
This invention deals with the problem of eliminating the degrading effects that unwanted radiation, outside of the field of view of a photographic system, can have on the quality of the final record contained in a photographic emulsion. The novel features illustrated in the preferred embodiment reside in the internal structural details and spatial configuration of an exposure chamber that forms part of a reflex photographic optical system. In effect, the interior of the chamber is an anti-glare structural arrangement that either directs the unwanted radiation to a location outside of the photosensitive area of the film, absorbs it, or decreases it to an intensity level below the response capability of the emulsion. The exposure chamber is an injection molded member of unitary construction made of an opaque plastic material. The shape of the exposure chamber may be described generally as a frustrum of an irregular quadrangular pyramind. One of the lateral walls of the chamber, a rear wall, is adapted to mount a mirror to reflect rays coming from an objective lens, mounted in a front wall, to the film plane which is formed in the base. The interior surfaces of the chamber are all smooth, specularly reflective, surfaces as opposed to having a rough matte finish. The smooth interior finish is achieved by polishing the mold used to fabricate the chamber. The reflection characteristics of the smooth surfaces vary as a function of the angle of incident radiation; the smaller the incident angle, the lower the reflected radiation. The chamber is divided into upper and lower sections by the addition of a single snap-in side wall baffle having specularly reflecting surfaces located approximately midway between the base and a top wall. In the upper section the angles of the side walls are carefully selected to direct a portion of the fan of unwanted rays through a multiple bounce path so that, at each bounce, these rays experience an approximate intensity loss of three stops compared with their initial intensity. Therefore, by the time they reach the photosensitive emulsion, their radiation intensity is insufficient to expose the emulsion. Another portion of the unwanted rays is directly blocked by the snap-in baffle. The remaining rays are allowed to reflect off the lower side wall whose angles are chosen to direct them to a location outside of the photosensitive area of the emulsion. In addition, the side walls of the lower section and the front wall of the upper section are provided with a plurality of internally molded serrations that are designed to act as radiation traps to further reduce the intensity of incident radiation by absorption. The exposure chamber as a result of its interior configuration occupies a minimum space closely approximating that of the bundle of the desired fan of rays within the system's field of view.
Accordingly, it is an object of the invention to provide a minimum sized anti-flare structure for use in a photographic optical system.
Another object of the invention is to provide an anti-flare structure for simplified manufacture.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features that are considered characteristic of the invention are set forth in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description when read in connection with the accompanying drawings wherein like numbers have been employed in the different figures to denote the same parts and wherein:
FIG. 1 is a cross-sectional elevational view of a simple, unfolded box-type optical system used to illustrate certain concepts related to the invention;
FIG. 2 is a cross-sectional view of the system of FIG. 1 including an objective lens bezel and is included to amplify on the inventive concepts;
FIG. 3 is structurally identical to FIG. 2 but includes additional ray tracing information used to further illustrate concepts related to the invention;
FIG. 4 is a cross-sectional elevational view of an unfolded optical system having certain optical characteristics identical to the system of FIG. 2 but including structure illustrative of an embodiment of the invention;
FIG. 5 is structurally identical to FIG. 4 but includes additional ray tracing information used to illustrate how the invention operates;
FIG. 6 is a graph showing the specular reflection characteristics of a plastic material used in fabricating the preferred embodiment;
FIG. 7 is a shematic representation of a serrated surface used in the preferred embodiment;
FIG. 8 is structurally identical to FIG. 5 and further includes additional information relating to the operation of the preferred embodiment;
FIG. 9 is a diagrammatic exploded perspective of the exposure chamber of the preferred embodiment;
FIG. 10 is a cross-sectional side elevational view of the exposure chamber of FIG. 9 including an objective lens assembly;
FIG. 11 is a cross-section front elevational view of the exposure chamber of FIG. 9;
FIG. 12 is a diagrammatic perspective of a snap-in specularly reflective surface member for use in the exposure chamber of FIG. 9; and
FIG. 13 is a segmented cross-sectional view taken along line 13--13 in FIG. 10;
INTRODUCTION
One of the major sources of poor quality photographs is the presence of "flare" light or unwanted radiation in images formed by photographic optical systems. Although flare has many sources, the present invention is concerned primarily with improving image quality by eliminating the effects of unwanted radiation that enters the optical system and has its origins outside the field of view of the optical system, but within the field of an objective lens that forms part of the system. The flare problem arises because photographic objectives will generally satisfactorily image a larger conjugate object area than is required to record the picture. Consequently, radiation from outside of the desired field of view of the system can be reflected off interior surfaces and eventually reach the photosensitive area of the film, that defines the limits of the picture. When this occurs, depending on the nature of the internal reflections, either extraneous or ghost images result or fogging occurs causing an overall reduction in the contrast of the final photograph.
In addition to providing a solution to the basic problem of "flare", the present invention is also concerned with the size and ease of manufacture of the structure that provides the basic solution. The two requirements, anti-flare and minimum size are somewhat mutually exclusive since the qualities which normally make a good anti-flare structure are generally inconsistent with small, simple structures that can be easily manufactured.
The novel features illustrated in the preferred embodiment of this invention reside in the internal structural detail and spatial configuration of an exposure chamber that forms part of a reflex photographic optical system. In effect, the interior of the chamber is an anti-flare structural arrangement that intercepts unwanted radiation and either directs the unwanted radiation to a location outside of the photosensitive area of the film, absorbs it, or decreases it to an intensity level below the response capability of the film prior to its impinging on it.
The peculiar characteristic of this invention which makes it work and distinguishes it from conventional approaches is a series of specularly reflective surfaces located on the interior of the exposure chamber. These specularly reflective surfaces represent a design anomaly considering the nature of the basic problem--the elimination of internal reflections. However, there is an explanation for this deviation from convention. It has its foundation in the following principle. If the designer carefully locates the path of all rays, both wanted and unwanted, entering the optical system through the objective lens, he can provide specularly reflective surfaces which intercept the identified unwanted rays and, by reflecting them, control their terminal point within the system. This is the crux of the invention. To understand its application in the preferred embodiment, the general design process will first be discussed by considering a simple straight through (unfolded) optical system and then explaining how the concepts involved in the general process relate to the preferred embodiment.
THE PROBLEM ILLUSTRATED
Consider the simple box-type optical system 10 illustrated in cross-section in FIG. 1. The system 10 includes a box-like housing 12 constructed of some suitable opaque material. The interior of the housing 10 defines an exposure chamber 14. On a forward wall 16 is mounted an objective positive lens 18. The lens 18 is mounted in alignment with an aperture 20 that permits light to enter the chamber 14. Opposite the forward wall 16 is a rear wall 22 having an exposure aperture 24 that permits light to leave the chamber 14. The spacing between the walls 16 and 22 is selected so that light entering the system 10 will be properly focused in a plane coincident with the exterior surface 26 of the rear wall 2. A pair of spaced apart edges 28 and 30 define the format of a film to be used with the system 10. It can be assumed that between the edges 28 and 30, the image quality is best, and that all cross-sections would be geometrically similar. To complete the description of the system 10, there are a pair of side walls, 32 and 34, that connect the front and rear walls, 16 and 22. It can be assumed that the side walls, 32 and 34, have strong specularly reflective surfaces.
Having completed the description, the optical characteristics of the system 10 will now be examined. The first step is to establish its field of view, or to put it another way, determine what area in object space will be imaged within the exposure aperture 24. Since an extended object may be regarded as an array of point sources, the location and size of the image formed can be determined by locating the respective images of the sources making up the object. This can be accomplished by calculating the paths of a number of rays from each object point through the optical system and applying Snell's Law at each ray-surface intersection is turn. Because there is a one-to-one relationship between object and image points, the process may obviously be reversed by projecting rays out of the system to determine the conjugate object area. Since the extremes are of interest, a fan of rays originating at the edges of the format, 28 and 30, are traced. It can be seen that a ray 36 and a ray 38 represent the extreme rays that will get out of the system 10 from the edge 28. Because symmetry applies, the extreme rays from the edge 30 are simply designated as rays 40 and 42. The angle subtended by the intersection of the rays 36 and 42, call it θ 1 , is a measure of the field of view of the system 10 and is called its field angle. Any rays that enter the system 10 and are outside of the field angle are unwanted radiation. A ray such as that designated as 44 would therefore be unwanted. Ray 44 can enter the system because the objective lens 18 is capable of imaging light outside the field of view of the system 10. Its effects are obvious. It first reflects off side wall 32 and reaches the exposure aperture 24 where is would create an extraneous image. This particular system poses serious flare problems because the field of the lens 18 is very close to 180°. In other words, it will transmit radiation from almost anything in front of it. There is one immediate and relatively simple way to alleviate this problem. The designer can limit the field of the lens with a lens shade or bezel that surrounds the lens and prevents some of the unwanted radiation from entering the system. FIG. 2 shows a bezel 46 extending from the forward wall 16 and in alignment with the objective lens 18. Notice a series of steps 48, the corners of which just touch the extreme rays, 36 and 42, which define the system field of view. If ray tracing is now used to determine what rays will enter the system 10, it's obvious that there are a class of rays such as that designated as 50 which the lens 18 cannot "see". Through an orderly ray tracing procedure, an extreme ray 52 is found which just enters the system 10. However, the ray 52 is still a problem since its reflected component has also reached the exposure aperture 24. Nevertheless, a significant reduction in the field of the lens 18 has been effected. It has gone from almost 180° to a substantially smaller field angle as illustrated in FIG. 3. The field of the lens 18 in combination with the bezel 46 is designated as θ 2 in FIG. 3 and is the angle subtended by the intersection of the extreme ray 52 and its symmetric counterpart, a ray 54. The designer is now in a position where he can begin to identify families of rays that fall within the category of unwanted radiation. The first, and most obvious family, includes all those rays that originate from within the angular segment formed by the intersection of the ray 36 and the ray 52. Likewise, between the ray 42 and the ray 54. For convenience, this angular segment is designated as Δθ in FIG. 3. A typical ray in this family is designated as the ray 56 in FIG. 3. Another family of rays has its origin outside of the field of view, θ 1 , of the system 10. A ray from this family is typified by a ray 58 in FIG. 3. The ray 58 is also characteristic of those rays having their origin outside the field of view of the system 10. Unwanted radiation, then, based on this analysis includes any ray entering the exposure chamber 14 from the field of the lens but outside of the field of view of the system and does not go directly to the exposure aperture 24. Having defined what is meant by unwanted radiation, it can be seen that there are segments of the side walls, 32 and 34, and the rear wall 22, where unwanted radiation strkes and, upon reflection, eventually would reach the photosensitive area of a film disposed within the exposure aperture 24. For convenience, these wall segments are bracketed and identified in FIG. 3. In Segment I, no radiation strikes. Segment II, however, receives all unwanted radiation. The question now is how to prevent the unwanted radiation from reaching the exposure aperture 34.
There are a variety of possibilities. Some of these will be discussed keeping in mind, however, the additional restrictions that the system must be of minimum size and must also be simple to manufacture. One approach, for example could be to roughen the surface of wall segment II in order to diffuse the unwanted radiation so it would not be image bearing. The roughened surface would have the effect of randomly scattering the unwanted radiation throughout the exposure chamber 14 thereby increasing the overall illumination level in the inside of the exposure chamber 14. This is obviously undesirable since this increase in illumination would reduce picture contrast. Another approach would be to spray the interior of the exposure chamber 14 with a dull, flat black paint. This suffers from two disadvantages. It would require a secondary operation and, as well, would not totally prevent specular reflections since even a dull surface specularly reflects some light when the incident angle of the radiation approaches the grazing angle. It would also include some diffuse light whose effects were previously discussed. Still another approach would be to line the interior of the chamber 14 with a light absorbant flocking material. This approach would produce good results but would complicate manufacture. The most conventional approach would be to erect baffles extending perpendicularly from the side walls toward the system's optical axis. This approach also would be quite effective. However, it does not reduce size and, in addition, would unduly complicate manufacture especially if the housing 12 were to be fabricated by plastic injection molding techniques. The mold, in this latter case, would necessarily have to be rather complicated in order to fabricate the perpendicularly extending baffles needed to achieve the desired result. Furthermore, if the side walls, 32 and 34, were moved toward the optical axis in order to reduce size, the number of baffles required would begin to increase geometrically. Obviously, this approach is inconsistent with the design goals.
PRINCIPLE OF OPERATION ILLUSTRATED IN NON-FOLDED EMBODIMENT
As mentioned earlier, the present invention is based on the principle that specularly reflective surfaces can be selectively placed in positions where they intercept unwanted radiation and ultimately control the disposition of the unwanted rays. This principle will now be discussed in terms of its application to the system 10.
First of all, the absolute minimum size that the system 10 could be reduced to would occur when the size walls 32 and 34, were made to exactly coincide with the rays, 38 and 40. It is apparent that specularly reflective surfaces so positioned would not work because all the unwanted radiation would ultimately reach the exposure aperture 24. By slightly backing away from this boundary and selecting angles for side walls oblique to the optical axis, it is possible to provide a plurality of specularly reflective surfaces that will do the job.
Such a system is illustrated in FIG. 4 where it is designated as 60. The system 60 and the system 10 are exactly the same with an apparent exception; housing 12 of the system 10 is much different than the structure of the system 60 designated as 62. Otherwise, the system 60 includes the same objective lens, 18', the same bezel, 46', the same entrance aperture, 20', and the same exposure aperture, 24'. The rays defining the field of view of the system 60 and the field of the objective lens 18' in combination with the bezel 46 are identical to those of the system 10. In other words, the unwanted radiation that entered the system 10 is identical with that entering the system 60. The exposure chamber of the system 60 is designated as 64.
The differences between the two systems exist in the structure 62. The structure 62 includes a pair of side walls, 66 and 68, the interior surfaces of which form oblique angles with respect to the optical axis of the system 60 and run generally lengthwise of the extreme rays 38' and 40' which define the field of view of the system 60. In the middle of the exposure chamber 64 are a pair of reflecting surfaces, 70 and 72, which extend inwardly from the side walls, 66 and 68. The edges of surfaces 70 and 72 terminate where they would just intersect the extreme rays 38' and 40' which define the limits of the bundle of rays that are contained in the field of view of the system 60 and are directly imaged in the exposure aperture 24'. The surfaces 70 and 72 also form oblique angles with respect to the optical axis. The position of the side walls, 66 and 68, closely hugging the rays 38' and 40', determine the size of the housing 62. In the direction of light traveling through the system 60, the side walls form a diverging type chamber which, assuming the surfaces 70 and 72 were not present, readily facilitates a simplified molding for fabrication purposes. This could be accomplished if the surfaces, 70 and 72, were contained in a separately molded piece that snaps into the side walls at the appropriate location. As will be seen later, the preferred embodiment does exactly this.
Assuming all the interior surfaces of the exposure chamber 64 to be specularly reflective, the disposition of unwanted radiation can be analyzed by again using ray tracing techniques. The rays to be considered will be those typical rays previously identified as belonging to certain families of unwanted radiation except will now be designated as primed (') numbers. For example, referring to FIG. 5, the ray 56' (from the Δθ segment) is now sent through a multiple bounce path prior to its intersecting the exposure aperture 24'. This at first seems no better than the system 10. However, each time the ray 56' reflects off a surface its intensity can be reduced by selecting a material that is a good absorber so that the intensity of the surface reflection is a low percentage of the incident value. In addition, the surface should not scatter incident radiation in a random fashion, but rather in accordance with Snell's law of reflection. These are the keys to the invention. The surface must be specularly reflective to control the ray path but should also have relatively low reflectivity and scattering properties. The perfect material and surface combination would obviously be one whose characteristics approached that of a perfect absorber, relecting no radiation. Since most thermoplastic materials suitable for making structures of this general type are not perfect absorbers, it is necessary to use one whose absorbtivity characteristics are sufficient to attenuate reflected radiation by being able to direct it through an appropriate bounce path in a predictable manner. An example of a suitable material having adequate characteristics, and used in the preferred embodiment with excellent results, is an Acrylonitrile/Buteidiene/Styrene synthetic polymeric (ABS) having an average surface finish of 4-10 microinches and blackened with carbon. The surface finish, which is equivalent to a No. 2 finish according to the Mold Finish Comparison Kit of the Society of Plastics Industry and Engineering, gives the material properties and the carbon makes it a good absorber of incident radiation. FIG. 6 shows a set of curves describing the specular reflection characteristics of the ABS used. It will be noted the reflectivity is direction sensitive; a property apparently related to the molecular structure of the surface and the fact that the ABS is a dielectric. This direction sensitivity, however, will not affect the operation of the invention unless a large percentage of the unwanted radiation is allowed to strike the polished surfaces at low incident angles and then reflected directly into the film. It will be seen that this is not permitted to occur in the present invention because of the positioning of the surfaces. In addition, the ABS with the No. 2 finish is an apparently good non-scattering surface since it is capable of forming sharp images of reflected objects. Curve 74 show the percentage reflectance as a function of incident angle and curve 76 shows the change in intensity in stops when calculated using the expression ##EQU1## What the graph in FIG. 6 illustrates is that incident radiation between 20° and 70° will experience a mean loss of approximately 2.5 stops per bounce. For the ray 56' shown in FIG. 5, the loss would be loss would be 10 stops since it undergoes four bounces. This is well outside the response range of most multicolor or black and white reversal films. In order to insure that this order of magnitude in intensity loss always occurs for rays like the ray 56', an additional feature which is employed in the preferred embodiment to enhance its performance will be discussed presently to demonstrate how it operates. However, it is understood that this feature is not absolutely essential. All of the reflecting surfaces of the exposure chamber 64, below the surfaces 70 and 72, may be provided with a plurality of serrations (see FIG. 7) whose major dimension, the length of the groove, forms the same oblique angle with the optical axis as the surface it is placed on. The angle of the grooves in the serrations must be less than 90°, and as FIG. 7 indicates, the preferred embodiment uses 60°, When a ray of light enters the serrations it is reflected a plurality of times until it is eventually absorbed as shown in FIG. 7.
Therefore, not only is a ray, like the ray 56', sent through a multiple bounce path before entering the exposure aperture 24', but it has a high probability of never reaching it as a result of the serrations in the lower part of the exposure chamber 64.
Consider another ray 78 that enters the system 60. Refer to FIG. 8 to trace its path. The path of the ray 78 is directly to the lower part of the chamber 64 where it is reflected into the area between the edge 28' of the exposure aperture 24' and the intersection of the side wall 66 with the rear wall 22'. All rays characterized by shallow angle intersections with either extreme rays 38' or 40', will directly hit the lower side wall and be directed to a location outside of the exposure aperture 24'. This is possible because the serrations do not run transverse to the direction of travel of these rays. There are many rays like the ray 80 (See FIG. 8) that are directly blocked by either the surface 70 or 72. Other rays typified by a ray 82 in FIG. 8 experience multiple bounces in the upper part of the chamber 64 prior to reaching exposure aperture 24' by being bounced off the surfaces, 70 and 72.
To summarize, the unwanted radiation is intercepted by specularly reflective surfaces with low reflectivity and is either directed through a multiple bounce path losing intensity at each bounce, is absorbed by serrations in selected surfaces, or is directed to a location outside of the exposure aperture. The design process involved determining the field of view of the system and the field of the lens as modified by the bezel, identifying unwanted radiation, and positioning specularly reflective surfaces at oblique angles to the system optical axis to intercept the unwanted radiation. The location of the surfaces were empirically determined using ray tracing techniques.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Although the preferred embodiment is an exposure chamber for use in a reflex photographic optical system, its principle of operation, the design process, and the problems it deals with have all previously been discussed. Its novel features are identical to those discussed with reference to the system 60 of FIG. 4. The single significant structural difference between the preferred embodiment and the system 60 is the inclusion of a mirror on a rear wall of the exposure chamber of the preferred embodiment. The mirror is used to fold the optical path in a system using the preferred embodiment. However, this structural difference in no way invalidates the principle of operation or design process when applied to the preferred embodiment. It is a difference in form between the preferred embodiment and the system 60 and not in substance. Therefore, the particular structural details of the preferred embodiment will be discussed with only as much reference to its detailed construction as is necessary to clarify its operation.
The preferred embodiment of the invention is illustrated in FIG. 9 as the exposure chamber designated as 90. The chamber 90 comprises an injection molded structural member 92. The member 92 is of unitary construction fabricated of an opaque plastic material (ABS), preferably black in color. The member 92 is formed of five wall sections including a front wall section 94, a top wall section 96, a pair of side wall sections, 98 and 100, and a rear wall section 102. The front wall section includes an inlet aperture 104. The bottom edges of the front wall sections 94, the side wall sections, 98 and 100, and the rear wall section 102 cooperate to define an exposure or outlet aperture 106. Integrally formed in the rear wall 102 is a trapezoidal shaped aperture 108 over which a mirror 110 is placed. Surrounding the perimeter of the aperture 108 on three sides is an outwardly extending flange 112 that is designed to cradle the mirror 110 and align it with the aperture 108. After the mirror 110 is placed over the aperture 108, it is retained in that position by a mirror retainer 114 that releasably engages with complimentary configured portions of the rear wall 102. In addition to retaining the mirror in position, the retainer 114 in cooperation with the outwardly extending flange 112 forms a labyrinth type light seal that prevents ambient radiation from passing through the aperture 108. Further details of this mirror mounting arrangement are disclosed in U.S. application Ser. No. 574,026, filed May 2, 1975. One important aspect, however, that is pointed out here is the fact that the edges of the aperture 108 define the limits of the effective reflecting area of the mirror 110.
With the mirror 110 retained in place on the rear wall section 102, it is clear that the mirror 110 and said wall sections that form the structural member 92 cooperate to define a light tight enclosure identified as 116 in both Figs. 9 and 10.
Referring to FIG. 10, it can be seen that the exterior of the front wall section 94 includes an outwardly extending flange 118 which surrounds the inlet aperture 104. The function of the flange 118 is to provide a means for mounting an objective lens assembly 120 including a bezel 122. The objective lens assembly 120 shown here is a Cooke Triplet type, but any lens suitable for photographic work may be adapted for use with the present invention, or alternatively, the present invention may be adapted for use with different photographic lenses. The lens assembly 120 has been included in FIG. 10 to illustrate how such a lens may be mounted to the structural member 92 and, in addition, to aide in explaining the invention. It should be noted that such lens assemblies need not be directly mounted to the flange 118. An alternative mounting scheme could optically couple the lens assembly 120 to the structural member 92 by first mounting the lens assembly 120 to a shutter or lens board and then mounting that assembly to the flange 118.
The optical path of radiation entering the exposure chamber 90 can be seen in FIG. 10. Radiation passes through the objective lens assembly 120 and enters the enclosure 116 through the inlet aperture 104. From there it strikes the mirror 110 where, by reflection, it is directed toward the exposure aperture 106. For example, an axial ray coincident with the optical axis strikes the mirror at a point 124 and subsequently intersects the exposure aperture 106 at a point 126 which corresponds to the center of the area of the exposure aperture 106. The field of view of the system, i.e., the exposure chamber 90 in combination with the objective lens assembly 120, can be determined by using the ray tracing method previously discussed in connection with the system 60. This system, however, unlike the system 60 does not have what corresponds to a masking aperture which defines an area in the exposure aperture 106 that would be the same size as the photosensitive area of a film used with the system. Rather, it is contemplated that the invention would be used with a film cassette that performs this function. Namely, a cassette such as that described in detail in U.S. Pat. 3,779,770 is of the type intended for use with this invention. The important relevant feature of this type cassette, at least for the present purposes, is that it includes a front wall section that has a masking aperture that limits the exposure area of the film. To illustrate this, such a cassette is shown in phantom in FIG. 10 where it is designated as 128. There the cassette 128 is shown disposed within the exposure aperture 106 in readiness to receive radiation. The limits of the exposure area defined by the aperture in the cassette 128 are shown as its edges 130 and 132. It is from these two points that rays are projected back out of the system to determine the system field of view. The extreme rays which define the system field of view are shown as rays 134 and 136. Unwanted radiation outside the field of view can be determined as before. Having identified the unwanted radiation, the procedure for determining the angles of the wall sections and reflecting surfaces intended to intercept it would proceed as previously discussed. An alternative analysis could be used, though. This would involve replacing the lens assembly 120 by a diffuse disk source whose size and location corresponds to the exit pupil of the lens assembly 120. It could then be assumed that the source radiated in all directions within the limits set by the extreme rays defining the field of the lens assembly. Once this had been done, a virtual image of the source can be used to replace the lens assembly. This is shown in FIG. 10. By continuing the projection of the rays 134 and 136 through the mirror 110 and measuring off the distance from point 124, along the optical axis, to the exit pupil of the lens assembly 120, the location of an equivalent disk source above the exposure aperture 106 can be determined. Such a source is indicated as 138. This procedure would convert the analysis to the unfolded equivalent system and the design procedure would follow as before. In particular, note the similarity between the system 60 in FIG. 4 and the preferred embodiment shown in FIG. 11. The only difference between the two that would have to be accounted for is the fact that rays emanating from the source 138 would not go directly to the exposure aperture 106 unless they fell within the aperture 108.
The internal features of the exposure chamber 90 will now be taken up. Referring to FIG. 10, there is seen a member 140 that approximately bisects the enclosure 116 into the upper and lower portions. The member 140 includes a pair of reflective surfaces 142 and 144 which form an oblique angle with respect to the optical axis of the system (See FIG. 11). The member 140 is a plastic insert that releasably snaps into engagement with complimentary configured portions of the side walls 98 and 100. In this connection, the member 140 has a pair of spaced apart vertical tabs, 146 and 148, that fit into a corresponding pair of spaced apart recesses, 150 and 152, molded into the side walls, 98 and 100. A front section 154 of the member 140, in cooperation with a pair of vertically extending ribs, only one of which is shown, 156, and a horizontal rib 160 form a rectangular baffle located behind the inlet aperture 104 (see FIGS. 9 and 10). Since these ribs run from the top wall section 96 toward the exposure aperture 106 they do not present a molding problem and, as well, aid in further limiting the quantity of unwanted radiation that can internally reflect from the various surfaces within the enclosure 116. Below the member 140 all of the walls include on their surfaces serrations similar to those previously described and whose cross-sections were illustrated in FIG. 7. These are designated as 162 in FIGS. 9, 10 and 11 and function as described previously. In addition, these serrations are included above the member 140 on the interior of the front wall 94 to minimize problems from radiation reflected from the mirror onto that surface. Notice again from FIG. 11 that the angles of the side walls, 98 and 100, and the surfaces, 142 and 144, are all oblique to the system optical axis. More-over, all of these surfaces, including the serrations, are all specularly reflective. The lateral edges of the aperture 108 include a series of steps 164 that function to reduce extraneous reflections off the mirror 110. These steps are shown in FIG. 13 which is a section taken along line 13--13 of FIG. 10.
The nature of the preferred embodiment shown is somewhat more complex than the unfolded system 60 used to explain its operation. But that complexity, the folding of the optical path by a mirror, is simply a matter of degree and does not alter the underlying principles of the invention. Whether the system is folded or not, the concept of applying to the interior of an exposure chamber a series of specularly reflective surfaces to intercept unwanted radiation to control its final disposition remains valid. The particular choice of the location of these surfaces and their angles will of course depend on the specific details of each optical system.
This invention may be practiced or embodied in still other ways without departing from its spirit or essential character. The embodiment described herein is therefore illustrative and not restrictive, the scope of the invention being indicated in the appended claims and all variations which come within the meaning of the claims are intended to be embraced thereby. | The internal configuration of a rigid opaque exposure chamber structure for use in a reflex photographic optical system is disclosed. The structure is a plastic, injection molded member of unitary construction. Its interior preferably includes an arrangement for receiving a single snap-in side wall having a specularly reflecting surface which, in combination with specularly reflecting side walls of the housing, either direct unwanted radiation from outside the field of view of the system away from its film plane or, alternatively, absorbs it by reducing its intensity through multiple reflections so that the quality of a final photograph will not be impaired. Selected side walls include serrated light traps to enhance the overall performance of the structure in this respect. | 6 |
BACKGROUND AND SUMMARY
[0001] The present application is a continuation of International Application No. PCT/SE2004/001926, filed Dec. 17, 2004, which claims priority to SE 0303446-9, filed Dec. 17, 2003, both of which are incorporated by reference.
[0002] The present invention relates to a process for use in a motor vehicle. The processes relate to an automatic gearshifting process with the vehicle in driving mode and a simultaneously engaged coupling-dependent power take off and automatic disengagement of said power take off with the vehicle in driving mode.
[0003] The power take off is disposed on the transmission of the vehicle.
[0004] In order rationally to be able to handle the load on a goods vehicle, load handling equipment is required. The most common examples of such equipment are tipper and crane. Other commonly found examples are load changer, garbage handling unit, rotary cement mixer, rinsing unit, refrigeration unit, pumping equipment for various types of liquids and air compressor for loading or unloading bulk loads.
[0005] In order to utilize the drive force of the vehicle engine to also drive the load-handling equipment, a power take off is required. The drive force from the power take off can either be transmitted mechanically via toothed gearings and shafts, chains or belts, or hydraulically by the fitting of a hydraulic pump on the power take off.
[0006] Power take offs are divided into coupling-independent and coupling-dependent power take offs. The coupling-dependent power take offs are mounted on the transmission and are usually driven by the intermediate shaft of the transmission. This means that the power take off is coupling-dependent, i.e., the power take off stops when the coupling between the engine and transmission of the vehicle is disconnected. Depending on whether the transmission is equipped with splitter gear or not, the gearing between the engine and the power take off can be affected.
[0007] Automatic transmissions of the automated step-geared transmissions type have become more and more common in heavy-duty vehicles as microcomputer technology has been increasingly developed and has made it possible, with a control computer and a number of controllers, for example servo motors, to precision-regulate engine speed, engagement and disengagement of an automated clutch between engine and transmission, as well as the internal coupling members of the transmission, in such a way and in such relation to one another that smooth gearshift is always obtained at the right speed.
[0008] The advantage with this type of automatic transmission compared with a traditional automatic transmission constructed with planetary gear steps and with a hydrodynamic torque converter on the input side is, firstly, that, particularly where there is a question of use in heavy-duty vehicles, it is simpler and more robust and can be produced at substantially lower cost than the traditional automatic transmission and, secondly, that it has higher efficiency, which means potentially lower fuel consumption.
[0009] According to the prior art, for the above-stated type of automated step-geared transmission, coupling-dependent power take offs are suitable for load-handling equipment which is used when the vehicle is stationary or is being driven only in start gear, for example tipper units, cranes, load changers, pumps for emptying/filling from various containers and air compressors for loading or unloading bulk loads.
[0010] U.S. Pat. No. 6,080,081 shows examples of a coupling-dependent power take off arrangement in a vehicle with automated step-geared transmission. The document deals with the engagement of the power take off.
[0011] It is general practice, in transmissions, to equip a gear with means for preventing unwanted disengagement in the transfer of torque at the gear. This in order to prevent accidental disengagement of the engaged gear.
[0012] Such means can be configured such that the coupling teeth, belonging to coupling sleeves forming part of the gear and to the disconnectable coupling rings of the gear wheels, are tapered such that mutually facing V-shaped ends of the teeth on the coupling sleeves and the coupling rings are wider than parts of the teeth remote from said ends. It is customary to say that the flanks of the coupling teeth are configured with “cutbacks”. An applied torque, for example the driving torque of the engine, on mutually contacting faces with cutbacks will produce a resultant force which acts in the direction of engagement of the coupling sleeve in order to stop an engaged gear from being accidentally disengaged. To enable an actuator disposed in the transmission to manage to disengage such a gear, torque applied to the gear must be reduced to the point where the actuator is able to disengage the gear. In order to minimize wear and possible damage, however, torquelessness is aimed for in the gear before it is disengaged. This can be effected, for example, by the transmission control unit, in a vehicle with an automatic step-geared transmission, ensuring that before the gear is disengaged the output torque of the engine is brought down to a minimum. Similar locking step to prevent accidental disengagement can also be found on coupling teeth in a claw clutch arranged to engage and disengage a coupling-dependent power take off in a vehicle. EP 1097018 shows examples of gear arrangements with cutbacks. As an alternative to cutbacks, the coupling teeth can be configured, for example, with more or less gradual variations in width, which width variations are meant to hook another when the engaging device is torque-loaded and thereby prevent accidental disengagement.
[0013] A problem with the prior art is that, in the case of an engaged coupling-dependent power take off, in which power is being tapped and in which a gear engaged in the transmission and equipped with means for preventing unwanted disengagement in the transfer of torque at the gear is simultaneously to be disengaged, the disengagement of the gear is unachievable, because of the said means.
[0014] Equivalent disengagement problems exist in power take offs in which the engaging/disengaging device of the power take off is constituted by a claw clutch with corresponding means for deterring accidental disengagement, i.e., through some form of coupling teeth with cutbacks. When a torque is applied to such power take offs through power tapping, a resultant force will therefore be generated, which acts in the direction of engagement of the claw clutch. According to the prior art, the vehicle needs to be stopped and the engine disconnected from the transmission in order to minimize the resultant force acting in the direction of engagement of the claw clutch and the power take off is thereby able to be disengaged.
[0015] Another problem with gearshifting with engaged coupling-dependent power take off is that the power tapping of the power take off affects the synchronization process. When so-called non-synchronized gears are engaged in automated step-geared transmissions, this problem can be circumvented by advanced controlling of the engine speed. In the case of engagement of so-called synchronized gears, the torque of the power take off will place load upon the synchronization, which produces increased wear and, for relatively large torque tappings, might also make synchronization impossible.
[0016] According to the prior art, the only way to ensure that the power take off does not load the transmission with any torque is by seeing to it that the power take off does not rotate. The driver of a vehicle with coupling-dependent power take off is therefore confined to using the coupling-dependent power take off when the vehicle is stationary or if a start gear is engaged, that the vehicle can be driven only in this gear whilst the power take off is engaged. Added to this are the difficulties in disengaging the power take off under load according to the above. In the case of gears and claw clutches without means for deterring accidental disengagement, comfort problems can also arise if the gear and/or the claw clutch are disengaged under torque load. These restrictions preclude the use of transmission-mounted coupling-dependent power take offs in a number of applications, including refrigeration/freezing transportations and driving rotary cement mixers.
[0017] There is therefore a need, in a vehicle equipped with power-dependent power take off and step-geared transmission, to be able to use the coupling-dependent power take off of the vehicle when the vehicle is in motion and with the facility to shift satisfactorily between all the gears of the vehicle over the full speed register of the vehicle and with the facility to disengage the power take off satisfactorily at any time during travel.
[0018] The first process according to the invention describes an automatic gearshifting process for a vehicle with engaged coupling-dependent power take off when the vehicle is in motion. The power take off is driven by an engine disposed in the vehicle via at least one clutch, which, in turn, is coupled to an automatic step-geared transmission in which there is disposed at least one intermediate shaft, used to drive the power take off. The transmission, the engine and the power take off are controlled by at least one control unit.
[0019] The gearshifting process is characterized in that the control unit limits the power tapping at the power take off during at least a part of the gearshifting process when the intermediate shaft is disconnected from the drive wheels of the vehicle with a view to limiting the torque load of the power take off across said transmission.
[0020] The limitation of the power tapping at the power take off lessens the torque load over the engaging/disengaging device of the transmission and thereby reduces the force required to disconnect the engaging/disengaging device, so that the transmission can be brought to a neutral position in which the power take off is disconnected from the output shaft of the transmission without comfort problems and without wear to the engagement/disengagement mechanism in the transmission. With the invention, it is therefore possible to shift gear when the vehicle is in motion, even when a coupling-dependent power take off is engaged and the starting position is that power is being tapped from the power take off. The facility to shift gear whilst the coupling-dependent power take off is engaged and the vehicle is in motion increases the number of possible types of auxiliary units which can be installed in the vehicle.
[0021] The second process according to the invention describes an automatic disengagement process of a coupling-dependent power take off in a vehicle when the vehicle is in motion. The power take off is driven by an engine disposed in the vehicle via a clutch, which, in turn, is coupled to an automatic step-geared transmission which drives the power take off. The transmission, the engine and the power take off are controlled by at least one control unit. The disengagement process comprises the steps: control unit limits the power tapping at the power take off, control unit disengages the power take off.
[0022] The advantage with the second process according to the invention is that the limitation of the power tapping from the power take off by the control unit lessens the applied torque and hence reduces the force required to disconnect the engaging/disengaging device of the power take off. The second process according to the invention therefore enables the control unit better to disengage the power take off when the vehicle is in motion, even when a coupling-dependent power take off is engaged and the starting position is that power is being tapped from the power take off.
[0023] According to one embodiment of the invention, the disengagement process comprises the steps: control unit limits the power tapping at the power take off; control unit disconnects the engine from the transmission; -the control unit puts the transmission into neutral position so that the power take off is disconnected from the drive wheels of the vehicle; control unit disengages the power take off.
[0024] The advantage with this embodiment is that the disconnection of the power take off both from the engine and from the drive wheels by the control unit ensures that only a very small torque loads the engaging device of the power take off as it is disconnected. The disconnection from the drive wheels can be realized by the power take off being disconnected from a main shaft disposed in the transmission or by a range gear disposed in the transmission being put into neutral position.
[0025] In a preferred embodiment based on any one of the above-stated processes, the control unit brings down the power tapping at the power take off to a minimum, i.e., zero power tapping or almost zero power tapping.
[0026] This ensures that the gear can be disengaged so that the transmission can assume neutral position and the control unit can engage a new gear and that the claw clutch can be disengaged. This produces increased comfort in the vehicle. A further advantage is that wear in the claw clutch and in the gear concerned is reduced.
[0027] In a further preferred embodiment based on any one of the above-stated processes, the gear and the claw clutch are respectively equipped with means for deterring accidental disengagement, i.e., coupling teeth with cutbacks, for example. The fact that, according to the invention, the control unit limits the power tapping from the power take off serves to reduce the applied torque and hence minimize the force required to disconnect the engaging/disengaging device of the gear and of the power take off respectively. It thereby becomes possible to shift gear or disengage the power take off even when the vehicle is in motion and despite the starting position being that power is being tapped from the power take off. It is therefore possible, with the aid of the processes according to the invention, to drive all types of unit by the coupling-dependent power take off in all gears, both forward and reverse, over the full speed register of the vehicle, irrespective of whether the vehicle is stationary or in motion. This also includes units which, according to the prior art, are required to be driven by a coupling-dependent power take off. Various configurations of units which are to be driven with power take off will hereby be easier to install in the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The present invention will be described in greater detail below with reference to the appended drawings, which, for illustrative purposes, show further preferred embodiments of the invention and the prior art.
[0029] FIG. 1 shows a diagrammatic representation of an internal combustion engine with connecting clutch and transmission with power take off.
[0030] FIG. 2 shows the clutch and the transmission in FIG. 1 on an enlarged scale.
DETAILED DESCRIPTION
[0031] In FIG. 1 , a six-cylinder internal combustion engine, for example a diesel engine, is denoted by 1 , the crankshaft 2 of which is coupled to a single-disk dry plate clutch denoted generally by 3 , which is enclosed in a clutch case 4 . The crankshaft 2 is non-rotatably connected by the output shaft 51 of the engine, which is connected with the flywheel (not shown), to the clutch housing 5 of the plate clutch 3 , whilst the plate disk 6 thereof is non-rotatably connected to an input shaft which is rotatably mounted in the housing 8 of a transmission denoted generally by 9 .
[0032] Also rotatably mounted in the housing 8 are a main shaft 10 and an intermediate shaft 11 .
[0033] As is most clearly apparent from FIG. 2 , a gear wheel 12 is rotatably mounted on the input shaft 7 such that it can be locked on the shaft with the aid of a coupling sleeve 13 , which is provided with synchronizing members and is mounted in a non-rotatable yet axially displaceable manner on a hub 14 non-rotatably connected to the input shaft 7 . With the aid of the coupling sleeve 13 , a gear wheel 15 rotatably mounted on the main shaft 10 is also lockable relative to the input shaft 7 . With the coupling sleeve 13 in a middle position, both of the gear wheels 12 and 15 are disconnected from their respective shafts 7 and 10 . The gear wheels 12 and 15 mesh with respective gear wheels 16 and 17 , which are non-rotatably connected to the intermediate shaft 11 . Disposed in a rotationally secure manner on the intermediate shaft 11 are further gear wheels 18 , 19 and 20 , which mesh with respective gear wheels 21 , 22 and 23 which are rotatably mounted on the main shaft 10 and can be locked on the main shaft with the aid of coupling sleeves 24 and 25 , which in the shown illustrative embodiment have no synchronizing devices. A further gear wheel 28 is rotatably mounted on the main shaft 10 and meshes with an intermediate gear wheel 30 which is mounted rotatably on a separate shaft 29 and which, in turn, meshes with the intermediate shaft gear wheel 20 . The gear wheel 28 can be locked on its shaft with the aid of a coupling sleeve 26 .
[0034] The gear wheel pairs 12 , 16 and 15 , 17 , and the coupling sleeve 13 , form a synchronized splitter gear having a low-gear step LS and a high-gear step HS. The gear wheel pair 15 , 17 also forms, together with the gear wheel pairs 21 , 18 , 22 , 19 , 23 , 20 and the three gear wheels 28 , 20 and 30 , a basic transmission having four forward gears and one reverse gear.
[0035] In the shown illustrative embodiment, the output end of the main shaft 10 is directly connected to the cardan shaft (not shown). In an alternative illustrative embodiment, the main shaft 10 can be coupled to the cardan shaft via, for example, a range gear step of the planetary type.
[0036] The coupling sleeves 13 , 24 , 25 and 26 are displaceable as shown by the arrows in FIG. 2 , producing the gear steps shown adjacent to the arrows. The respective coupling sleeve 13 , 24 , 25 has three positions, two gear positions and one neutral position (the middle position). The coupling sleeve 26 has one gear position and one neutral position. The displacement of the respective coupling sleeve is achieved with servo elements (actuators) 40 , 41 , 42 and 43 , indicated diagrammatically in FIG. 2 , which can be pneumatically operated piston cylinder devices of the type utilized in a transmission of the kind described above, which is marketed under the designation The servo elements 40 , 41 , 42 and 43 are controlled by an electronic control unit 45 (see FIG. 1 ), comprising a microcomputer, in dependence on signals fed into the control unit and representing various engine and vehicle data, which at least comprise engine speed, vehicle speed, gas pedal position and, where appropriate, engine brake on-off, when an electronic gear selector 46 , coupled to the control unit 45 , is in its automatic gear position. When the selector is in the manual gearshift position, the gearshift is effected on command of the driver via the gear selector 46 .
[0037] The control unit 45 can request engine speed engine torque of the engine control unit 50 controlling the fuel injection.
[0038] In FIGS. 1 and 2 , 32 denotes a coupling-dependent power take off coupled to the intermediate shaft 11 .
[0039] The power take off usually consists of a housing (not shown) mounted on the side or rear end face of the transmission 9 . The input shaft 36 of the power take off 32 can be connected by an engagement and disengaging device 35 in a rotationally secure manner to the intermediate shaft. 11 . The engagement and disengaging device 35 of the power take off 32 is controlled by the control unit 45 . The control unit 45 receives a request for engagement and disengagement of the power take off 32 from a device 33 for controlling the power take off 32 , which device 33 is connected to the control unit 45 .
[0040] The device 33 can be a control which is regulated by the driver of the vehicle, or an automatic arrangement which, via some form of sensor, for example, detects a parameter variation, thereby initiating engagement or disengagement of the power take off 32 . When the power take off 32 is engaged, it is therefore driven by the engine 1 via the plate clutch 3 , splitter gear 12 , 16 or 15 , 17 and the intermediate shaft 11 . The power take off 32 is usually equipped with one or more gearing facilities on the at least one output shaft (not shown) of the power take off. To the output shaft of the power take off 32 there is coupled a desired unit, which is to be driven.
[0041] According to one embodiment of the process according to the invention, gearshifting is enabled when the coupling-dependent power take off is engaged and the vehicle is in motion and when, prior to the gearshifting, power is tapped from the power take off.
[0042] According to this embodiment of the invention, the control unit 45 is programmed to register that the power take off 32 is engaged. This can be done by sensors (not shown) for detecting whether the power take off 32 is engaged or disengaged, or in another known manner, for example by registering the status of the device 33 for controlling the power take off 32 .
[0043] When the control unit 45 registers that the power take off 32 is engaged, the control unit 45 controls the transmission 9 according to the gearshifting process according to the invention. When the control unit 45 , according to the gearshifting process according to the invention, decides on a gearshift, for example from gear 3 to gear 4 , the control unit 45 limits the power tapping at the power take off 32 to a minimum by controlling an apparatus connected up to the power take off, for example in the form of a hydraulic pump (not shown) driving an optional auxiliary unit (not shown).
[0044] The hydraulic pump can be controlled in such a way that the control unit 45 fully opens a bypass valve disposed in the hydraulic pump. The power tapping, and hence the torque which contributes to the resultant force acting in the direction of engagement of the coupling ring 24 , i.e., towards 3rd gear, is thereby minimized. Once the power tapping at the power take off 32 is minimized, the control unit 45 controls the speed of the engine 1 so that the input shaft 7 becomes torqueless. Torque registration in the input shaft 7 of the transmission 9 can be realized with the aid of a torque transmitter 27 disposed on the input shaft 7 , or alternatively on the basis of engine torque calculated from the supplied quantity of fuel, with deduction for engine friction and other losses encumbering the engine 1 (generator, cooling fan, coupling-independent power take off). By knowing the torque on the input shaft 7 of the transmission, it is possible to control the torque of the engine 1 so that the input shaft is torqueless or almost torqueless.
[0045] Once the input shaft 7 is torqueless and the contributory torque of the power take off has been minimized, the 3 rd gear in the basic transmission can be disengaged easily and with minimal wear upon the component parts of the particular gear. The transmission is therefore in its neutral position, i.e., the intermediate shaft 11 is disconnected from the drive wheels of the vehicle and the power take off 32 continues to be driven by the engine 1 via the clutch 3 , the input shaft 7 of the transmission and the intermediate shaft 11 . There will however be an interruption in the driving of the auxiliary unit, since the bypass valve of the hydraulic pump is temporarily fully opened.
[0046] If, after the transmission 9 has been put in neutral position, the control unit 45 decides to engage 4th gear, then the control unit 45 controls the speed of the engine 1 so that the speed of the engine 1 and of the intermediate shaft 11 becomes synchronous with the 4th gear. The control unit 45 delivers a signal in a known manner to, in this case, a servo element 41 to engage 4th gear. Registration of when synchronous speed has been achieved is realized in known fashion, for example by a tachometer (not shown).
[0047] Once 4th gear is engaged, the control unit 45 restores the previous level for the power tapping at the power take off 32 . The control unit 45 therefore closes the bypass valve to the position which it had prior to commencement of the gearshifting.
[0048] In an alternative method for carrying out the gearshift, the control unit 45 , after the transmission has been put in neutral position and, moreover, the plate clutch 3 has been disconnected, can synchronize the speed of the intermediate shaft 11 to the speed of the main shaft 10 by controlling an intermediate shaft brake 34 . The intermediate shaft 11 can be braked with both the power take off 32 and the intermediate shaft brake 34 , or just one of the power take off 32 and the intermediate shaft brake 34 .
[0049] In another alternative embodiment, 4 th gear or all the gears in the basic transmission are synchronized (not shown). The speed adjustment to a chosen gear is effected, in this case, with the aid of mechanical synchronizing devices which are disposed on each gear and are known per se, in the form of, for example, synchronizing rings with associated synchronizing parts. Such a synchronizing device is indicated in the figures by the conical coupling sleeve 13 , which forms part of the synchronized splitter gear 12 , 13 , 14 , 15 .
[0050] According to a further embodiment of the process according to the invention, disengagement of the coupling-dependent power take off is enabled when the vehicle is in motion and when, prior to the disengagement, power is tapped from the power take off.
[0051] Here too, the control unit 45 can be programmed to register that the power take off 32 is engaged. The control unit 45 registers a request for disengagement of the power take off 32 from the device 33 for controlling the power take off 32 . The control unit 45 limits the power tapping at the power take off 32 according to the above, so that the torque on the engaging/disengaging device 35 , which can be constituted by a claw clutch, is minimized. After this, the control unit 45 disengages the power take off with minimized wear and with minimal torque effect.
[0052] In a further embodiment of the process according to the invention, disengagement of the coupling-dependent power take off is enabled, as in the abovementioned embodiment, when the vehicle is in motion and when, prior to the disengagement, power is tapped from the power take off 32 . According to this process, the power take off 32 is disengaged in association with the transmission 9 being brought into a neutral position.
[0053] This process can advantageously be used under the same procedure as a gearshift in the transmission 9 . The process is registered by following a gearshift from 3rd gear into 4th gear.
[0054] The control unit 45 registers that disengagement of the power take off 32 is requested. The control unit 45 limits the power tapping at the power take off 32 to a minimum. The control unit 45 decides to shift from 3rd gear to 4th. The control unit 45 then controls the engine 1 so that the input shaft 7 becomes as torqueless as possible. The control unit 45 disconnects the engine 1 from the transmission 9 by disengagement of the plate clutch 3 . In an alternative embodiment of the invention, the engine 1 is disconnected from the transmission 9 by the splitter gear 12 , 13 , 14 , 15 being put into its neutral position. When the engine 1 has been disconnected from the transmission 9 , the control unit 45 disengages 3rd gear and the transmission 9 is in its neutral position. The control unit then disengages the power take off 32 . After this, the control unit 45 couples together the engine 1 and the transmission 9 . The control unit 45 controls the speed of the engine 1 so that the speed of the engine 1 and of the intermediate shaft 11 becomes synchronous with the 4th gear. The control system 45 delivers a signal in a known manner to, in this case, a servo element 41 to engage 4th gear.
[0055] The gearshift of a transmission equipped with a range gearing is realized preferably the range gearshift parallel with the gearshift of a basic gear, i.e., when the transmission 9 is in neutral position. The range gearshift per se is realized in a known manner simultaneous with a basic gearshift according to the above-described processes according to the invention. According to an advantageous embodiment of the invention, the control unit 45 is programmed to adjust the gear selection in the basic transmission with regard to equipment (not shown) driven by the power take off 32 and the rest of the current or future state of the vehicle.
[0056] According to an alternative embodiment of the invention, the control unit 45 is programmed to limit the power tapping of the power take off in all gearshifts, regardless of whether the power take off 32 is engaged or not, alternatively the control unit 45 can be programmed to limit the power tapping of the power take off 32 only in those gearshifts when the power take off 32 is engaged. The control unit 45 can also be programmed such that the power tapping of the power take off 32 is limited only during gearshifts between certain gear steps, for example so that the power tapping of the power take off 32 is not limited in a gearshift involving only the splitter gear 12 , 13 , 14 , 15 of the transmission 9 .
[0057] In an alternative embodiment of the invention, the transmission 9 can be put into neutral position by a range gear (not shown) disposed in the transmission being put into its neutral position. The intermediate shaft 11 is therefore disconnected from the drive wheels of the vehicle.
[0058] The invention can also be applied to transmissions without splitter gear.
[0059] The gearshifting process for the transmission or the disengagements of the power take off according to the invention can be realized by the execution of a computer program in a data processor disposed in the control unit 45 .
[0060] A computer program according to the invention comprises a program code for, with a device disposed in the vehicle and in a predefined manner, gearshifting of the transmission 9 with engaged coupling-dependent power take off 32 or disengaging a coupling-dependent power take off 32 when a program is executed by a data processor integrated in or coupled to any of the control units of the vehicle.
[0061] The computer program according to the invention can be stored on a medium which is readable by a computer system integrated in the device. This medium can be, for example, a data diskette, a memory module, a CD or the like. This can be advantageous, for example, when the program is to be downloaded in the vehicle in production when the program in the vehicle is to be updated. The updating of software can take place, for example, at scheduled services or, if so desired, directly by a customer. The updating of software can also be realized via a connection, for example by internet, to a server in which the program is stored.
[0062] In the present application, the use of terms such as “including” is open-ended and is intended to have the same meaning as terms such as “comprising” and not preclude the presence of other structure, material, or acts. Similarly, though the use of terms such as “can” or “may” is intended to be open-ended and to reflect that structure, material, or acts are not necessary, the failure to use such terms is not intended to reflect that structure, material, or acts are essential. To the extent that structure, material, or acts are presently considered to be essential, they are identified as such.
[0063] The invention should not be deemed to be limited to the illustrative embodiments described above, but rather a number of further variants and modifications are conceivable within the scope of the following patent claims. | An automatic gearshifting process and/or disengagement process of a coupling-dependent power take off for a vehicle with the power take off engaged and when the vehicle is in motion. The power tapping at the power take off is minimized before a gearshift and/or disengagement of the claw clutch of the power take off takes place. One advantage is that gearshifting can be realized with engaged coupling-dependent power take off. Comfort is increased and coupling teeth wear is minimized, whilst, at the same time, a gear and the claw clutch of the power take off are able to be securely disengaged. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of U.S. patent application Ser. No. 12/638,252, filed Dec. 15, 2009 (issuing as U.S. Pat. No. 8,196,650 on Jun. 12, 2012), which was a non-provisional application of U.S. Provisional Patent Application Ser. No. 61/122,434, filed Dec. 15, 2008. Each of these applications are incorporated herein by reference and to which priority is claimed.
[0002] U.S. Pat. No. 7,281,589, issued Oct. 16, 2007 is incorporated herein by reference.
[0003] U.S. Pat. No. 7,681,646, issued Mar. 23, 2010 is incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0004] Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
[0005] Not applicable
BACKGROUND
[0006] In top drive rigs, the use of a top drive unit, or top drive power unit is employed to rotate drill pipe, or well string in a well bore. Top drive rigs can include spaced guide rails and a drive frame movable along the guide rails and guiding the top drive power unit. The traveling block supports the drive frame through a hook and swivel, and the driving block is used to lower or raise the drive frame along the guide rails. For rotating the drill or well string, the top drive power unit includes a motor connected by gear means with a rotatable member both of which are supported by the drive frame.
[0007] During drilling operations, when it is desired to “trip” the drill pipe or well string into or out of the well bore, the drive frame can be lowered or raised. Additionally, during servicing operations, the drill string can be moved longitudinally into or out of the well bore.
[0008] The stem of the swivel communicates with the upper end of the rotatable member of the power unit in a manner well known to those skilled in the art for supplying fluid, such as a drilling fluid or mud, through the top drive unit and into the drill or work string. The swivel allows drilling fluid to pass through and be supplied to the drill or well string connected to the lower end of the rotatable member of the top drive power unit as the drill string is rotated and/or moved up and down.
[0009] Top drive rigs also can include elevators are secured to and suspended from the frame, the elevators being employed when it is desired to lower joints of drill string into the well bore, or remove such joints from the well bore.
[0010] At various times top drive operations, beyond drilling fluid, require various substances to be pumped downhole, such as cement, chemicals, epoxy resins, or the like. In many cases it is desirable to supply such substances at the same time as the top drive unit is rotating and/or moving the drill or well string up and/or down, but bypassing the top drive's power unit so that the substances do not damage/impair the unit. Additionally, it is desirable to supply such substances without interfering with and/or intermittently stopping longitudinal and/or rotational movement by the top drive unit of the drill or well string.
[0011] A need exists for a device facilitating insertion of various substances downhole through the drill or well string, bypassing the top drive unit, while at the same time allowing the top drive unit to rotate and/or move the drill or well string.
[0012] One example includes cementing a string of well bore casing. In some casing operations it is considered good practice to rotate the string of casing when it is being cemented in the wellbore. Such rotation is believed to facilitate better cement distribution and spread inside the annular space between the casing's exterior and interior of the well bore. In such operations the top drive unit can be used to both support and continuously rotate/intermittently reciprocate the string of casing while cement is pumped down the string's interior. During this time it is desirable to by-pass the top drive unit to avoid possible damage to any of its portions or components.
[0013] The following U.S. Patents are incorporated herein by reference: U.S. Pat. Nos. 4,722,389 and 7,007,753.
[0014] While certain novel features of this invention shown and described below are pointed out in the annexed claims, the invention is not intended to be limited to the details specified, since a person of ordinary skill in the relevant art will understand that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation may be made without departing in any way from the spirit of the present invention. No feature of the invention is critical or essential unless it is expressly stated as being “critical” or “essential.”
BRIEF SUMMARY
[0015] The apparatus of the present invention solves the problems confronted in the art in a simple and straightforward manner. One embodiment relates to an assembly having a top drive arrangement for rotating and longitudinally moving a drill or well string. In one embodiment is provided a swivel apparatus, the swivel generally comprising a mandrel and a sleeve with a packing configuration, the swivel being especially useful for top drive rigs.
[0016] In one embodiment the sleeve can be rotatably and sealably connected to the mandrel. The swivel can be incorporated into a drill or well string, enabling string sections both above and below the sleeve to be rotated in relation to the sleeve. Additionally, the swivel provides a flow path between the exterior of the sleeve and interior of the mandrel while the drill string is being rotated and/or being moved in a longitudinal direction (up or down). The interior of the mandrel can be fluidly connected to the longitudinal bore of the casing or drill string thereby providing a flow path from the exterior of the sleeve to the interior of the casing/drill string.
[0017] In one embodiment is provided a method and apparatus for servicing a well wherein a swivel is connected to a top drive unit for conveying pumpable substances from an external supply through the swivel for discharge into the well string and bypassing the top drive unit.
[0018] In another embodiment is provided a method of conducting servicing operations in a well bore, such as cementing, comprising the steps of moving a top drive unit rotationally and/or longitudinally to provide longitudinal movement and/or rotation in the well bore of a well string suspended from the top drive unit, rotating the drill or well string and supplying a pumpable substance to the well bore in which the drill or well string is manipulated by introducing the pumpable substance at a point below the top drive power unit and into the well string.
[0019] In other embodiments are provided a swivel placed below the top drive unit can be used to perform jobs such as spotting pills, squeeze work, open formation integrity work, kill jobs, fishing tool operations with high pressure pumps, sub-sea stack testing, rotation of casing during side tracking, and gravel pack or frack jobs. In still other embodiments a top drive swivel can be used in a method of pumping loss circulation material (LCM) into a well to plug/seal areas of downhole fluid loss to the formation and in high speed milling jobs using cutting tools to address down hole obstructions. In other embodiments the top drive swivel can be used with free point indicators and shot string or cord to free stuck pipe where pumpable substances are pumped downhole at the same time the downhole string/pipe/free point indicator is being rotated and/or reciprocated. In still other embodiments the top drive swivel can be used for setting hook wall packers and washing sand.
[0020] In still other embodiments the top drive swivel can be used for pumping pumpable substances downhole when repairs/servicing is being done to the top drive unit and rotation of the downhole drill string is being accomplished by the rotary table. Such use for rotation and pumping can prevent sticking/seizing of the drill string downhole. In this application safety valves, such as TIW valves, can be placed above and below the top drive swivel to enable routing of fluid flow and to ensure well control.
[0021] The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0022] For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:
[0023] FIGS. 1A and 1B are a schematic views showing a top drive rig with one embodiment of a top drive swivel incorporated in the drill string;
[0024] FIG. 2 is a perspective view of one embodiment of a top drive swivel;
[0025] FIG. 3 is a sectional view of a mandrel which can be incorporated in the swivel of FIG. 2 ;
[0026] FIG. 4 is a perspective view of a sleeve, clamp, and torque arm which can be incorporated into the swivel of FIG. 2 ;
[0027] FIG. 5 is an exploded view of the sleeve, clamp, and torque arm of FIG. 4 ;
[0028] FIG. 6 is a cutaway perspective view of the swivel of FIG. 2 ;
[0029] FIGS. 7A and 7B include a sectional view of the swivel of FIG. 2 along with an enlarged sectional view of the packing area;
[0030] FIG. 8 is an exploded view of a set of packing which can be incorporated into the swivel of FIG. 2 ;
[0031] FIG. 9 is a perspective view of a spacer;
[0032] FIG. 10 is a top view of the spacer of FIG. 9 ;
[0033] FIG. 11A is a sectional side view of the spacer of FIG. 9 ;
[0034] FIG. 11B is an enlarged sectional side view of the spacer of FIG. 9 ;
[0035] FIG. 12 is a perspective view of a female backup ring;
[0036] FIG. 13 is a top view of the female backup ring of FIG. 12 ;
[0037] FIG. 14A is a sectional side view of the female backup ring of FIG. 12 ;
[0038] FIG. 14B is an enlarged sectional side view of the female backup ring of FIG. 12 ;
[0039] FIG. 15 is a perspective view of a seal ring;
[0040] FIG. 16 is a top view of the seal ring of FIG. 15 ;
[0041] FIG. 17A is a sectional side view of the seal ring of FIG. 15 ;
[0042] FIG. 17B is an enlarged sectional side view of the seal ring of FIG. 15 ;
[0043] FIG. 18 is a perspective view of a rope seal;
[0044] FIG. 19 is a top view of the rope seal of FIG. 18 ;
[0045] FIG. 20A is a sectional side view of the rope seal of FIG. 18 ;
[0046] FIG. 20B is an enlarged sectional side view of the rope seal of FIG. 18 ;
[0047] FIG. 21 is a perspective view of a seal ring;
[0048] FIG. 22 is a top view of the seal ring of FIG. 21 ;
[0049] FIG. 23A is a sectional side view of the seal ring of FIG. 21 ;
[0050] FIG. 23B is an enlarged sectional side view of the seal ring of FIG. 21 ;
[0051] FIG. 24 is a perspective view of a seal ring;
[0052] FIG. 25 is a top view of the seal ring of FIG. 24 ;
[0053] FIG. 26A is a sectional side view of the seal ring of FIG. 24 ;
[0054] FIG. 26B is an enlarged sectional side view of the seal ring of FIG. 24 ;
[0055] FIG. 27 is a perspective view of a male backup ring;
[0056] FIG. 28 is a top view of the male backup ring of FIG. 27 ;
[0057] FIG. 29A is a sectional side view of the male backup ring of FIG. 27 ;
[0058] FIG. 29B is an enlarged sectional side view of the male backup ring of FIG. 27 ;
[0059] FIGS. 30A and 30B include a sectional view of another embodiment of the swivel of FIG. 2 along with an enlarged sectional view of the packing area;
[0060] FIG. 31 is an exploded view of a set of packing which can be incorporated into the swivel of FIG. 30A ;
[0061] FIG. 32 is a perspective view of a spacer;
[0062] FIG. 33 is a top view of the spacer of FIG. 32 ;
[0063] FIG. 34A is a sectional side view of the spacer of FIG. 32 ;
[0064] FIG. 34B is an enlarged sectional side view of the spacer of FIG. 32 ;
[0065] FIG. 35 is a perspective view of a female backup ring;
[0066] FIG. 36 is a top view of the female backup ring of FIG. 35 ;
[0067] FIG. 37A is a sectional side view of the female backup ring of FIG. 35 ;
[0068] FIG. 37B is an enlarged sectional side view of the female backup ring of FIG. 35 ;
[0069] FIG. 38 is a perspective view of a seal ring;
[0070] FIG. 39 is a top view of the seal ring of FIG. 38 ;
[0071] FIG. 40A is a sectional side view of the seal ring of FIG. 38 ;
[0072] FIG. 40B is an enlarged sectional side view of the seal ring of FIG. 38 ;
[0073] FIG. 41 is a perspective view of a rope seal;
[0074] FIG. 42 is a top view of the rope seal of FIG. 41 ;
[0075] FIG. 43A is a sectional side view of the rope seal of FIG. 41 ;
[0076] FIG. 43B is an enlarged sectional side view of the rope seal of FIG. 41 ;
[0077] FIG. 44 is a perspective view of a seal ring;
[0078] FIG. 45 is a top view of the seal ring of FIG. 44 ;
[0079] FIG. 46A is a sectional side view of the seal ring of FIG. 44 ;
[0080] FIG. 46B is an enlarged sectional side view of the seal ring of FIG. 44 ;
[0081] FIG. 47 is a perspective view of a seal ring;
[0082] FIG. 48 is a top view of the seal ring of FIG. 47 ;
[0083] FIG. 49A is a sectional side view of the seal ring of FIG. 47 ;
[0084] FIG. 49B is an enlarged sectional side view of the seal ring of FIG. 47 ;
[0085] FIG. 50 is a perspective view of a male backup ring;
[0086] FIG. 51 is a top view of the male backup ring of FIG. 50 ;
[0087] FIG. 52A is a sectional side view of the male backup ring of FIG. 50 ;
[0088] FIG. 52B is an enlarged sectional side view of the male backup ring of FIG. 50 ;
[0089] FIG. 53 shows an alternative combination swivel and ball dropper;
[0090] FIG. 54 shows one embodiment of the ball dropper for the combination swivel and ball dropper of FIG. 53 .
DETAILED DESCRIPTION
[0091] Detailed descriptions of one or more preferred embodiments are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in any appropriate system, structure or manner.
[0092] FIGS. 1A and 1B are schematic views showing a top drive rig 1 with one embodiment of a top drive swivel 30 incorporated into drill string 20 . FIG. 1A shows a rig 1 having a top drive unit 10 . Rig 1 comprises supports 16 , 17 ; crown block 2 ; traveling block 4 ; and hook 5 . Draw works 11 uses cable 12 to move up and down traveling block 4 , top drive unit 10 , and drill string 20 . Traveling block 4 supports top drive unit 10 . Top drive unit 10 supports drill string 20 .
[0093] During drilling operations, top drive unit 10 can be used to rotate drill string 20 which enters wellbore 14 . Top drive unit 10 can ride along guide rails 15 as unit 10 is moved up and down. Guide rails 15 prevent top drive unit 10 itself from rotating as top drive unit 10 rotates drill string 20 . During drilling operations drilling fluid can be supplied downhole through drilling fluid line 8 and gooseneck 6 .
[0094] As shown in FIG. 1B , during operations swivel 30 can be connected to rig 1 through clamp 600 and torque arm 630 . Torque are 630 can be pivotally connected to swivel 30 and can resist rotational movement of swivel sleeve 150 relative to rig 1 . Torque arm 630 can be slidably connected to rig 1 to allow a certain amount of longitudinal movement of swivel 30 with drill string 20 .
[0095] At various times top drive operations, beyond drilling fluid, require substances to be pumped downhole, such as cement, chemicals, epoxy resins, or the like. In many cases it is desirable to supply such substances at the same time as top drive unit 10 is rotating and/or moving drill or well string 20 up and/or down and bypassing top drive unit 10 so that the substances do not damage/impair top drive unit 10 . Additionally, it is desirable to supply such substances without interfering with and/or intermittently stopping longitudinal and/or rotational movements of drill or well string 20 being moved/rotated by top drive unit 10 . This can be accomplished by using top drive swivel 30 .
[0096] Top drive swivel 30 can be installed between top drive unit 10 and drill string 20 . One or more joints of drill pipe 18 can be placed between top drive unit 10 and swivel 30 . Additionally, a valve can be placed between top drive swivel 30 and top drive unit 10 . Pumpable substances can be pumped through hose 31 , swivel 30 , and into the interior of drill string 20 thereby bypassing top drive unit 10 . Top drive swivel 30 is preferably sized to be connected to drill string 20 such as 4½ inch (11.43 centimeter) IF API drill pipe or the size of the drill pipe to which swivel 30 is connected to. However, cross-over subs can also be used between top drive swivel 30 and connections to drill string 20 . Two sizes for swivel 30 will be addressed in this application—a 4½ inch (11.43 centimeter) version and a 6⅝ inch (16.83 centimeter) version.
[0097] FIG. 2 is a perspective view of one embodiment of a swivel 30 . Swivel 30 can be comprised of mandrel 40 and sleeve 150 . Sleeve 150 can be rotatably and sealably connected to mandrel 40 . Accordingly, when mandrel 40 is rotated, sleeve 150 can remain stationary to an observer insofar as rotation is concerned. As will be discussed later inlet 200 of sleeve 150 is and remains fluidly connected to a the central longitudinal passage 90 of mandrel 40 . Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 .
[0098] FIG. 3 is a sectional view of mandrel 40 which can be incorporated in swivel 30 . Mandrel 40 can be comprised of upper end 50 and lower end 60 . Central longitudinal passage 90 can extend from upper end 50 through lower end 60 . Lower end 60 can include a pin connection 80 or any other conventional connection. Upper end 50 can include box connection 70 or any other conventional connection. Mandrel 40 can in effect become a part of drill string 20 . Sleeve 150 can fit over mandrel 40 and become rotatably and sealably connected to mandrel 40 . Mandrel 40 can include shoulder 100 to support sleeve 150 . Mandrel 40 can include one or more radial inlet ports 140 fluidly connecting central longitudinal passage 90 to recessed area 130 . Recessed area 130 preferably forms a circumferential recess along the perimeter of mandrel 40 and between packing support areas 131 , 132 . In such manner recessed area 130 will remain fluidly connected with radial passage 190 and inlet 200 of sleeve 150 (see FIGS. 6 and 7A ).
[0099] Mandrel 40 takes substantially all of the structural load from drill string 20 . In one embodiment the overall length of mandrel 40 is preferably 52 and 5/16 inches (132.87 centimeters). Mandrel 40 can be machined from a single continuous piece of heat treated steel bar stock. NC50 is preferably the API Tool Joint Designation for the box connection 70 and pin connection 80 . Such tool joint designation is equivalent to and interchangeable with 4½ inch (11.43 centimeter) IF (Internally Flush), 5 inch (12.7 centimeter) XH (Extra Hole) and 5½ inch (13.97 centimeter) DSL (Double Stream Line) connections. Additionally, it is preferred that the box connection 70 and pin connection 80 meet the requirements of API specifications 7 and 7G for new rotary shouldered tool joint connections having 6⅝ inch (16.83 centimeters) outer diameter and a 2¾ inch (6.99 centimeter) inner diameter. The Strength and Design Formulas of API 7G—Appendix A provides the following load carrying specification for mandrel 40 of top drive swivel 30 : (a) 1,477,000 pounds (6,570 kilo newtons) tensile load at the minimum yield stress; (b) 62,000 foot-pounds (84 kilo newton meters) torsional load at the minimum torsional yield stress; and (c) 37,200 foot-pounds (50.44 kilo newton meters) recommended minimum make up torque. Mandrel 40 can be machined from 4340 heat treated bar stock.
[0100] In another embodiment, Mandrel 40 takes substantially all of the structural load from drill string 20 . In one embodiment the overall length of mandrel 40 is preferably 67 and 13/16 inches (172.24 centimeters). Mandrel 40 can be machined from a single continuous piece of heat treated steel bar stock. 6⅝ inch (16.83 centimeters) FH is preferably the API Tool Joint Designation for the box connection 70 and pin connection 80 . Additionally, it is preferred that the box connection 70 and pin connection 80 meet the requirements of API specifications 7 and 7G for new rotary shouldered tool joint connections having 8½ inch (21.59 centimeter) outer diameter and a 4¼ inch (10.8 centimeter) inner diameter. The Strength and Design Formulas of API 7G—Appendix A provides the following load carrying specification for mandrel 40 of top drive swivel 30 : (a) 2,094,661 pounds (9,318 kilo newtons) tensile load at the minimum yield stress; (b) 109,255 foot-pounds (148.1 kilo newton meters) torsion load at the minimum torsional yield stress; and (c) 65,012 foot-pounds (88.14 kilo newton meters) recommended minimum make up torque. Mandrel 40 can be machined from 4340 heat treated bar stock.
[0101] To reduce friction between mandrel 40 and packing units 305 , 405 and increase the life expectancy of packing units 305 , 405 , packing support areas 131 , 132 can be coated and/or sprayed welded with a materials of various compositions, such as hard chrome, nickel/chrome or nickel/aluminum (95 percent nickel and 5 percent aluminum) A material which can be used for coating by spray welding is the chrome alloy TAFA 95MX Ultrahard Wire (Armacor M) manufactured by TAFA Technologies, Inc., 146 Pembroke Road, Concord N.H. TAFA 95 MX is an alloy of the following composition: Chromium 30 percent; Boron 6 percent; Manganese 3 percent; Silicon 3 percent; and Iron balance. The TAFA 95 MX can be combined with a chrome steel. Another material which can be used for coating by spray welding is TAFA BONDARC WIRE-75B manufactured by TAFA Technologies, Inc. TAFA BONDARC WIRE-75B is an alloy containing the following elements: Nickel 94 percent; Aluminum 4.6 percent; Titanium 0.6 percent; Iron 0.4 percent; Manganese 0.3 percent; Cobalt 0.2 percent; Molybdenum 0.1 percent; Copper 0.1 percent; and Chromium 0.1 percent. Another material which can be used for coating by spray welding is the nickel chrome alloy TAFALOY NICKEL-CHROME-MOLY WIRE-71T manufactured by TAFA Technologies, Inc. TAFALOY NICKEL-CHROME-MOLY WIRE-71T is an alloy containing the following elements: Nickel 61.2 percent; Chromium 22 percent; Iron 3 percent; Molybdenum 9 percent; Tantalum 3 percent; and Cobalt 1 percent. Various combinations of the above alloys can also be used for the coating/spray welding. Packing support areas 131 , 132 can also be coated by a plating method, such as electroplating. The surface of support areas 131 , 132 can be ground/polished/finished to a desired finish to reduce friction and wear between support areas 131 , 132 and packing units 305 , 415 .
[0102] FIG. 4 is a perspective view of a sleeve 150 , clamp 600 , and torque arm 630 which can be incorporated into swivel 30 . FIG. 5 is an exploded view of the components shown in FIG. 4 . FIG. 6 is a cutaway perspective view of swivel 30 . FIG. 7A is a sectional view of swivel 30 taken along the line 7 A- 7 A of FIG. 6 .
[0103] FIG. 6 is an overall perspective view (and partial sectional view) of top drive swivel 30 . Sleeve 150 is shown rotatably connected to mandrel 40 . Bearings 145 , 146 allow sleeve 150 to rotate in relation to mandrel 40 . Packing units 305 , 405 sealingly connect sleeve 150 to mandrel 40 . Retaining nut 800 retains sleeve 150 on mandrel 40 . Inlet 200 of sleeve 150 is fluidly connected to central longitudinal passage 90 of mandrel 40 . Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 . Recessed area 130 forms a peripheral recess between mandrel 40 and sleeve 150 . The fluid pathway from inlet 200 to outlet at lower end 60 of central longitudinal passage 90 is as follows: entering inlet 200 ; passing through radial passage 190 ; passing through recessed area 130 ; passing through one of the plurality of radial inlet ports 40 ; passing through central longitudinal passage 90 ; and exiting mandrel 40 through central longitudinal passage 90 at lower end 60 and pin connection 80 .
[0104] Sleeve 150 can include central longitudinal passage 180 extending from upper end 160 through lower end 170 . Sleeve 150 can also include radial passage 190 and inlet 200 . Inlet 200 can be attached by welding or any other conventional type method of fastening such as a threaded connection. If welded the connection is preferably heat treated to remove residual stresses created by the welding procedure. Lubrication port 210 (not shown) can be included to provide lubrication for interior bearings. Packing ports 220 , 230 can also be included to provide the option of injecting packing material into the packing units 305 , 405 . A protective cover 240 can be placed around packing port 230 to protect packing injector 235 . Optionally, a second protective cover can be placed around packing port 220 . Sleeve 150 can include a groove 691 for insertion of a key 700 . FIG. 7A illustrates how central longitudinal passage 90 is fluidly connected to inlet 200 through radial passage 190 .
[0105] Sleeve 150 slides over mandrel 40 . Bearings 145 , 146 rotatably connect sleeve 150 to mandrel 40 . Bearings 145 , 146 are preferably thrust bearings although many conventionally available bearing will adequately function, including conical and ball bearings. Packing units 305 , 405 sealingly connect sleeve 150 to mandrel 40 . Inlet 200 of sleeve 150 is and remains fluidly connected to central longitudinal passage 90 of mandrel 40 . Accordingly, while mandrel 40 is being rotated and/or moved up and down pumpable substances can enter inlet 200 and exit central longitudinal passage 90 at lower end 60 of mandrel 40 . Recessed area 130 forms a peripheral recess between mandrel 40 and sleeve 150 . The fluid pathway from inlet 200 to outlet at lower end 60 of central longitudinal passage 90 is as follows: entering inlet 200 (arrow 201 ); passing through radial passage 190 (arrow 202 ); passing through recessed area 130 (arrow 202 ); passing through one of the plurality of radial inlet ports 140 (arrow 202 ), passing through central longitudinal passage 90 (arrow 203 ); and exiting mandrel 40 via lower end 60 at pin connection 80 (arrows 204 , 205 ).
[0106] Sleeve 150 is preferably fabricated from 4140 heat treated round mechanical tubing having the following properties: (120,000 psi (827,400 kilo pascal) minimum tensile strength, 100,000 psi (689,500 kilo pascal) minimum yield strength, and 285/311 Brinell Hardness Range). In one embodiment the external diameter of sleeve 150 is preferably about 11 inches (27.94 centimeters). Sleeve 150 preferably resists high internal pressures of fluid passing through inlet 200 . Preferably top drive swivel 30 with sleeve 150 will withstand a hydrostatic pressure test of 12,500 psi (86,200 kilo pascal). At this pressure the stress induced in sleeve 150 is preferably only about 24.8 percent of its material's yield strength. At a preferable working pressure of 7,500 psi (51,700 kilo pascal), there is preferably a 6.7:1 structural safety factor for sleeve 150 .
[0107] To minimize flow restrictions through top drive swivel 30 , large open areas 140 are preferred. Preferably each area of interest throughout top drive swivel 30 is larger than the inlet service port area 200 . Inlet 200 is preferably 3 inches having a flow area of 4.19 square inches (27.03 square centimeters). In one embodiment the flow area of the annular space between sleeve 150 and mandrel 40 is preferably 20.81 square inches (134.22 square centimeters). The flow area through the plurality of radial inlet ports 140 is preferably 7.36 square inches (47.47 square centimeters). The flow area through central longitudinal bore 90 is preferably 5.94 square inches 38.31 square centimeters).
[0108] Retainer nut 800 can be used to maintain sleeve 150 on mandrel 40 . Retainer nut 800 can threadably engage mandrel 40 at threaded area 801 . Set screw 890 can be used to lock in place retainer nut 800 and prevent nut 800 from loosening during operation. A set screw 890 (not shown for clarity) can threadably engages retainer nut 800 through bore 900 (not shown for clarity) and sets in one of a plurality of receiving portions 910 formed in mandrel 40 . Retaining nut 800 can also include grease injection fitting 880 for lubricating bearing 145 . A wiper ring 271 (not shown for clarity) can be set in area 270 protects against dirt and other items from entering between the sleeve 150 and mandrel 40 . A grease ring 291 (not shown for clarity) can be set in area 290 for holding lubricant for bearing 145 .
[0109] Bearing 146 can be lubricated through a grease injection fitting 211 and lubrication port 210 (not shown for clarity).
[0110] FIGS. 4 and 5 best show clamp 600 which can be incorporated into top drive swivel 30 . FIG. 5 is an exploded view of clamp 600 . Clamp 600 can comprises first portion 610 , second portion 620 , and third portion 625 . First, second, and third portions 610 , 620 , 625 can be removably attached by plurality of fasteners 670 , 680 . Key 700 can be inserted in keyway 690 of clamp 600 . A corresponding keyway 691 is included in sleeve 150 of top drive swivel 30 . Keyways 690 , 691 and key 700 prevent clamp 600 from rotating relative to sleeve 150 . A second key 720 can be installed in keyways 710 , 711 . Third, fourth, and additional keys/keyways can be used as desired.
[0111] Shackles can be attached to clamp 600 to facilitate handing top drive swivel 30 when clamp 600 is attached. Torque arm 630 can be pivotally attached to clamp 600 and allow attachment of clamp 600 (and sleeve 150 ) to a stationary part of top drive rig 1 preventing sleeve 150 from rotating while drill string 20 is being rotated by top drive 10 (and top drive swivel 30 is installed in drill string 20 ). Torque arm 630 can be provided with holes for attaching restraining shackles. Restrained torque arm 630 prevents sleeve 150 from rotating while mandrel 40 is being spun. Otherwise, frictional forces between packing units 305 , 405 and packing support areas 131 , 135 of rotating mandrel 40 would tend to also rotate sleeve 150 . Clamp 600 is preferably fabricated from 4140 heat treated steel being machined to fit around sleeve 150 .
[0112] FIG. 8 shows a blown up schematic view of packing unit 305 . FIGS. 7B shows a sectional view through packing area 305 . Packing unit 305 can comprise female packing end 330 ; packing ring 340 , packing lubrication ring 350 , packing ring 360 , packing ring 370 , and packing end 380 . Packing unit 305 sealing connects mandrel 40 and sleeve 150 . Packing unit 305 can be encased by packing retainer nut 310 , spacer 320 , and shoulder 156 of protruding section 155 . Packing retainer nut 310 can be a ring which threadably engages sleeve 150 at threaded area 316 . Packing retainer nut 310 and shoulder 156 squeeze packing unit 305 to obtain a good seal between mandrel 40 and sleeve 150 . Set screw 315 can be used to lock packing retainer nut 310 in place and prevent retainer nut 310 from loosening during operation. Set screw 315 can be threaded into bore 314 and lock into receiving area 317 on sleeve 150 . Packing unit 405 (shown in FIG. 7A ) can be constructed substantially similar to packing unit 305 . The materials for packing unit 305 and packing unit 405 can be similar.
[0113] Spacer 320 can comprise, first end 322 , second end 324 , internal surface 326 , and external surface 328 . Spacer 320 can be sized based on the amount of squeezed to be applied to packing unit 305 when packing retainer nut 310 is tightened. It is preferably fabricated or machined from bronze.
[0114] Packing end 330 is preferably a female packing end comprised of a bearing grade peak or stiffened bronze material. Female packing ring or end 330 can comprise tip 332 with concave portion 331 . Concave portion 331 can have an angle of about 130 degrees at its center. Tip 332 can include side 333 , recessed area 334 , peripheral groove 337 and inner diameter 335 . Recessed area 334 and inner diameter 335 can be configured to minimize contact of female packing ring or end 330 with mandrel 40 . Instead, contact will be made between packing ring 340 and mandrel 40 . It is believed that minimizing contact between female packing ring or end 330 and mandrel 40 will reduce heat buildup from friction and extend the life of the packing unit. It is also believed that packing ring 340 performs the great majority of sealing against high pressure fluids (such as pressures above about 3,000 or about 4,000 psi (20,700 kilo pascals or 27,600 kilo pascals)). It is also believed that packing rings 370 and/or 360 perform the majority of sealing against lower pressure fluids. Female packing ring 330 can include a plurality of radial ports 336 fluidly connecting peripheral groove 337 with interior groove 338 to allow packing injected to evenly distribute around ring and into the actual sealing rings.
[0115] Packing ring 340 can comprise tip 342 , base 344 , internal surface 346 , and external surface 348 . Tip 342 can have an angle of about 120 degrees to have an non-interference fit with tip 332 of female packing end 330 which is at about 130 degrees Base 344 can have an angle of about 120 degrees. Packing ring 340 is preferably a “Vee” packing ring—comprised of bronze filled teflon such as that supplied by CDI material number 714 . Tip 342 of packing ring 340 is made at about 120 degrees (which is blunter than the conventional 90 degree tips) in an attempt to limit the braking effect (e.g., caused by expansion of recessed area 334 of the female packing ring or end 330 which would cause side 333 of female packing ring to contact mandrel 40 ) on mandrel 40 when longitudinal force is applied through the packing Base 344 being at about 120 degrees is believed to assist in causing packing ring 340 to bear against mandrel 40 , and not side 333 of female packing ring 330 .
[0116] Packing lubrication ring 350 , preferably includes at least one rope seal such as a Garlock ½ inch (or 7/16 inch or ⅜ inch) (1.27 centimeters, or 1.11 centimeters, or 0.95 centimeters) section 8913 Rope Seal. Rope seals have surprisingly been found to extend the life of other seals in the packing unit. This is thought to be by secretion of lubricants, such as graphite, during use over time. Although shown in a “Vee” type shape, rope seals typically have a square cross section and form to the shape of the area to which they are confined. Here, lubrication ring 350 is shown after be shaped by packing rings 340 and 360 .
[0117] Packing ring 360 can comprise tip 362 , base 364 , internal surface 366 , and external surface 368 . Tip 362 can have an angle of about 90 degrees. Base 364 can have an angle of about 120 degrees. 90 degrees for the tip and 120 degrees for the base are conventional angles. The larger angle for the base allows thermal expansion of the tip in the base. Packing ring 360 is preferably a “Vee” packing ring—comprised of hard rubber such as that supplied by CDI material number 850 or viton such as that supplied by CDI material number 951 .
[0118] Packing rings 360 , 370 can have substantially the same geometric construction.
[0119] Packing ring 370 can comprise tip 372 , base 374 , internal surface 376 , and external surface 378 . Tip 372 can have an angle of about 90 degrees. Base 374 can have an angle of about 120 degrees. 90 degrees for the tip and 120 degrees for the base are conventional angles. The larger angle for the base allows thermal expansion of the tip in the base. Packing ring 370 is preferably a “Vee” packing ring—comprised of teflon such as that supplied by CDI material number 711 .
[0120] In an alternative embodiment both packing rings 360 and 370 are“Vee” packing rings—comprised of teflon such as that supplied by CDI material number 711 .
[0121] In another alternative embodiment packing ring 370 can be a “Vee” packing ring—comprised of hard rubber such as that supplied by CDI material number 850 or viton such as that supplied by CDI material number 951 ; and Packing ring 360 can be a “Vee” packing ring—comprised of teflon such as that supplied by CDI material number 711 .
[0122] Male packing end or ring 380 can comprise tip 382 , base 384 , internal surface 386 , and external surface 388 . Tip 382 can have an angle of about 90 degrees. Packing end 380 is preferably an aluminum bronze male packing ring.
[0123] Various alternative materials for packing rings can be used such as standard chevron packing rings of standard packing materials.
[0124] Using the above packing configuration it has been surprisingly found that packing life in a displacement job at high pressure can be extended from about 45 minutes to about 10 hours, at rotation speeds of about 30, about 40, about 50, and about 60 revolutions per minute.
[0125] In installing packing units 305 , 405 , it has been found that the packing units should first be compressed in a longitudinal direction between sleeve 150 and a dummy cylinder (the dummy cylinder serving as mandrel 40 ) before sleeve 150 is installed on mandrel 40 . This is because a certain amount of longitudinal compression of packing units 305 , 405 will occur when fluid pressure is first exerted on these packing units. This longitudinal compression will be taken up by the respective packing retainer nuts 310 . However, using a dummy cylinder allows the individual packing retainer nuts 310 to cause pre-fluid pressure longitudinal compression on packing units 305 , 405 , but still allow the seals to maintain an internal diameter consistent with the external diameter of mandrel 40 . Such a procedure can avoid the requirement of resetting the individual packing retainer nuts 310 after fluid pressure is applied to the packing units causing longitudinal compression.
[0126] Female packing ring or end 330 can include a packing injection option. Injection fitting 225 can be used to inject additional packing material such as teflon into packing unit 305 . Head 226 for injection fitting 225 can be removed and packing material can then be inserted into fitting 225 . Head 226 can then be screwed back into injection fitting 225 which would push packing material through fitting 225 and into packing port 220 . The material would then be pushed into packing ring or end 330 . Packing ring or end 330 can comprise a plurality of radial ports 336 , outer peripheral groove 337 , and inner peripheral groove 338 . The material would proceed through outer groove 337 , through the plurality of radial ports 336 , and through inner peripheral groove 338 causing a sealing effect. The interaction between injection fitting 235 and packing unit 405 can be substantially similar to the interaction between injection fitting 225 and packing unit 305 . A conventionally available material which can be used for packing injection fittings 225 , 235 is DESCO™ 625 Pak part number 6242-12 in the form of a 1 inch by ⅜ inch (2.54 centimeter by 0.95 centimeter) stick and distributed by Chemola Division of South Coast Products, Inc., Houston, Tex.
[0127] Injection fittings 225 , 235 have a dual purpose: (a) provide an operator a visual indication whether there has been any leakage past either packing units 305 , 405 and (b) allow the operator to easily inject additional packing material and stop seal leakage without removing top drive swivel 30 from drill string 20 .
[0128] FIGS. 30A through 50 show an alternative packing arrangement for packing units 305 , 405 . In this alternative arrangement spacer 420 can include a plurality of radial ports for injecting packing filler material.
[0129] FIG. 31 shows a blown up schematic view of packing unit 405 . FIGS. 30B shows a sectional view through packing unit 405 . Packing unit 405 can comprise female packing end 430 ; packing ring 440 , packing lubrication ring 450 , packing ring 460 , packing ring 470 , and packing end 480 . Packing unit 405 sealing connects mandrel 40 and sleeve 150 . Packing unit 405 can be encased by packing retainer nut 310 , spacer 420 , and shoulder 156 of protruding section 155 . Packing retainer nut 310 can be a ring which threadably engages sleeve 150 at threaded area 316 . Packing retainer nut 310 and shoulder 156 squeeze packing unit 405 to obtain a good seal between mandrel 40 and sleeve 150 . Set screw 315 can be used to lock packing retainer nut 310 in place and prevent retainer nut 310 from loosening during operation. Set screw 315 can be threaded into bore 314 and lock into receiving area 317 on sleeve 150 . An upper packing unit can be constructed substantially similar to packing unit 405 . The materials for packing unit 405 and upper packing unit can be similar.
[0130] Spacer 420 can comprise, first end 421 , second end 422 , internal surface 423 , and external surface 424 . Spacer 420 can be sized based on the amount of squeezed to be applied to packing unit 405 when packing retainer nut 310 is tightened. It is preferably fabricated or machined from bronze.
[0131] Packing end 430 is preferably a female packing end comprised of a bearing grade peak or stiffened bronze material. Female packing ring or end 430 can comprise tip 432 with concave portion 431 . Concave portion 431 can have an angle of about 130 degrees at its center. Tip 442 can include side 433 , recessed area 44 , peripheral groove 47 and inner diameter 445 . Recessed area 434 and inner diameter 435 can be configured to minimize contact of female packing ring or end 430 with mandrel 40 . Instead, contact will be made between packing ring 440 and mandrel 40 . It is believed that minimizing contact between female packing ring or end 430 and mandrel 40 will reduce heat buildup from friction and extend the life of the packing unit. It is also believed that packing ring 440 performs the great majority of sealing against high pressure fluids (such as pressures above about 3,000 or about 4,000 psi) (20,700 kilo pascals or 27,600 kilo pascals). It is also believed that packing rings 470 and/or 460 perform the majority of sealing against lower pressure fluids.
[0132] Packing ring 440 can comprise tip 442 , base 444 , internal surface 446 , and external surface 448 . Tip 442 can have an angle of about 120 degrees to have an non-interference fit with tip 432 of female packing end 430 which is at about 130 degrees Base 444 can have an angle of about 120 degrees. Packing ring 440 is preferably a “Vee” packing ring—comprised of bronze filled teflon such as that supplied by CDI material number 714 . Tip 442 of packing ring 440 is made at about 120 degrees (which is blunter than the conventional 90 degree tips) in an attempt to limit the braking effect (e.g., caused by expansion of recessed area 434 of the female packing ring or end 430 which would cause side 433 of female packing ring to contact mandrel 40 ) on mandrel 40 when longitudinal force is applied through the packing Base 444 being at about 120 degrees is believed to assist in causing packing ring 440 to bear against mandrel 40 , and not side 433 of female packing ring 430 .
[0133] Packing lubrication ring 450 , preferably includes at least one rope seal such as a Garlock ½ inch (or 7/16 inch or ⅜ inch) (1.27 centimeters, or 1.11 centimeters, or 0.95 centimeters) section 8913 Rope Seal. Rope seals have surprisingly been found to extend the life of other seals in the packing unit. This is thought to be by secretion of lubricants, such as graphite, during use over time. Although shown in a “Vee” type shape, rope seals typically have a square cross section and form to the shape of the area to which they are confined. Here, lubrication ring 450 is shown after being shaped by packing rings 440 and 460 .
[0134] Packing ring 460 can comprise tip 462 , base 464 , internal surface 466 , and external surface 468 . Tip 462 can have an angle of about 90 degrees. Base 464 can have an angle of about 120 degrees. 90 degrees for the tip and 120 degrees for the base are conventional angles. The larger angle for the base allows thermal expansion of the tip in the base. Packing ring 460 is preferably a “Vee” packing ring—comprised of hard rubber such as that supplied by CDI material number 850 or viton such as that supplied by CDI material number 951 .
[0135] Packing rings 460 , 470 can have substantially the same geometric construction. Packing ring 470 can comprise tip 472 , base 474 , internal surface 476 , and external surface 478 . Tip 472 can have an angle of about 90 degrees. Base 474 can have an angle of about 120 degrees. 90 degrees for the tip and 120 degrees for the base are conventional angles. The larger angle for the base allows thermal expansion of the tip in the base. Packing ring 470 is preferably a “Vee” packing ring—comprised of teflon such as that supplied by CDI material number 711 .
[0136] In an alternative embodiment both packing rings 460 and 470 are“Vee” packing rings—comprised of teflon such as that supplied by CDI material number 711 .
[0137] In another alternative embodiment packing ring 470 can be a “Vee” packing ring—comprised of hard rubber such as that supplied by CDI material number 850 or viton such as that supplied by CDI material number 951 ; and Packing ring 460 can be a “Vee” packing ring—comprised of teflon such as that supplied by CDI material number 711 .
[0138] Male packing end or ring 480 can comprise tip 482 , base 484 , internal surface 486 , and external surface 488 . Tip 482 can have an angle of about 90 degrees. Packing end 480 is preferably an aluminum bronze male packing ring.
[0139] Various alternative materials for packing rings can be used such as standard chevron packing rings of standard packing materials.
[0140] FIG. 53 shows an alternative combination swivel and ball dropper.
[0141] FIG. 54 shows one embodiment of the ball dropper for the combination swivel and ball dropper of FIG. 53 .
[0142] The following is a list of reference numerals:
[0000]
LIST FOR REFERENCE NUMERALS
(Part No.)
(Description)
Reference Numeral
Description
1
rig
2
crown block
3
cable means
4
travelling block
5
hook
6
gooseneck
7
swivel
8
drilling fluid line
10
top drive unit
11
draw works
12
cable
13
rotary table
14
well bore
15
guide rail
16
support
17
support
18
drill pipe
19
drill string
20
drill string or work string
30
swivel
31
hose
40
swivel mandrel
50
upper end
60
lower end
70
box connection
80
pin connection
90
central longitudinal passage
100
shoulder
110
interior surface
120
external surface (mandrel)
130
recessed area
131
packing support area
132
packing support area
140
radial inlet ports (a plurality)
145
bearing
146
bearing
150
swivel sleeve
155
protruding section
156
shoulder
157
shoulder
158
packing support area
159
packing support area
160
upper end
170
lower end
180
central longitudinal passage
190
radial passage
200
inlet
201
arrow
202
arrow
203
arrow
204
arrow
205
arrow
210
lubrication port
211
grease injection fitting
220
packing port
225
injection fitting
226
head
230
packing port
235
injection fitting
240
cover
250
upper shoulder
260
lower shoulder
270
area for wiper ring
271
wiper ring (preferably Parker part number 959-65)
280
area for wiper ring
281
wiper ring (preferably Parker part number 959-65)
290
area for grease ring
291
grease ring (preferably Parker part number
2501000 Standard Polypak)
300
area for grease ring
301
grease ring (preferably Parker part number
2501000 Standard Polypak)
305
packing unit
310
packing retainer nut
314
bore for set screw
315
set screw for packing retainer nut
316
threaded area
317
set screw for receiving area
320
spacer
322
first end
324
second end
326
internal surface
328
external surface
330
female packing end and packing injection ring
331
concave portion
332
tip
333
side
334
recessed area
335
inner diameter
336
radial port
337
peripheral groove
338
interior groove
340
packing ring
342
tip
344
base
346
internal surface
348
external surface
350
packing ring
360
packing ring
362
tip
364
base
366
internal surface
368
external surface
370
packing ring
372
tip
374
base
376
internal surface
378
external surface
380
packing end
382
tip
384
base
386
internal surface
388
external surface
405
packing unit
410
packing retainer nut
414
bore for set screw
415
set screw for packing retainer nut
416
threaded area
417
set screw for receiving area
420
spacer and packing injection ring
421
first end
422
second end
423
internal surface
424
external surface
437
radial port
438
peripheral groove
439
interior groove
430
female packing end
431
concave portion
432
tip
433
side
434
recessed area
435
inner diameter
436
external diameter
440
packing ring
442
tip
444
base
446
internal surface
448
external surface
450
packing ring
460
packing ring
462
tip
464
base
466
internal surface
468
external surface
470
packing ring
472
tip
474
base
476
internal surface
478
external surface
480
packing end
482
tip
484
base
486
internal surface
488
external surface
600
clamp
605
groove
610
first portion
620
second portion
625
third portion
630
torque arm
650
shackle
660
shackle
670
plurality of fasteners
680
plurality of fasteners
690
keyway
691
keyway
700
key
710
keyway
711
keyway
720
key
[0143] All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise.
[0144] It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention set forth in the appended claims. The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. | For use with a top drive power unit supported for connection with a well string in a well bore to selectively impart longitudinal and/or rotational movement to the well string, a feeder for supplying a pumpable substance such as cement and the like from an external supply source to the interior of the well string in the well bore without first discharging it through the top drive power unit including a mandrel extending through a sleeve which is sealably and rotatably supported thereon for relative rotation between the sleeve and mandrel. The mandrel and sleeve have flow passages for communicating the pumpable substance from an external source to discharge through the sleeve and mandrel and into the interior of the well string below the top drive power unit. The unit can include a packing injection system and novel seal configuration. | 4 |
FIELD OF THE INVENTION
This invention is directed to N-allyl-N-dialkoxyethyl amide or amine monomers, their preparation, and their use as crosslinking agents in emulsion copolymers that can be thermoset without the release of formaldehyde. This invention is further directed to nonwoven fabrics bonded with those emulsion copolymers and a process for the preparation of those nonwoven fabrics.
BACKGROUND OF THE INVENTION
Emulsion polymers are widely used to bind nonwoven fibers into fabrics for use as facings or topsheets in diapers, bed pads, hospital gowns, and other such uses. The typical emulsion polymers for this use are prepared predominantly from ethylene, vinyl acetate, vinyl chloride and acrylate esters in combination with styrene or acrylonitrile, and use N-methylolacrylamide as the cross-linking agent. Although N-methylolacrylamide is widely used in the industry and provides excellent wet and dry tensile strength to the nonwoven fabrics, it suffers from two major drawbacks. N-methylolacrylamide is an equilibrium composition of acrylamide with free formaldehyde. Formaldehyde is a suspected carcinogen. A latex that uses N-methylolacrylamide as a latent crosslinking monomer will contain quantities of free formaldehyde, and consequently the nonwoven substrates bound with emulsion polymers containing N-methylolacrylamide will contain detectable quantities of free formaldehyde. In addition, acrylamide derivatives, including N-methylol acrylamide, are capable of undergoing strongly exothermic homopolymerization reactions, which makes processing, transportation and storage of acrylamides difficult.
The N-allyl-N-dialkoxyethylamide or amine monomer of the present invention is not in equilibrium with free formaldehyde, yet it provides latent crosslinking ability similar to the N-methylolacrylamide compounds. It also does not undergo strongly exothermic homopolymerization reactions.
U.S. Pat. No. 4,788,288, issued to Pinschmidt, Jr. et al., discloses N-olefinically substituted cyclic hemiamidals and hemiamide ketals, and N-olefinically substituted dialkyl acetals and ketals, which can be incorporated into free radical addition polymers to give formaldehyde-free compositions. U.S. Pat. No. 4,959,489 issued to Nordcuist et al. discloses a process for making an N-substituted acrylamide containing dialkyl acetal groups. However, the starting materials for some of these compositions are expensive and there is still a need for inexpensive formaldehyde-free compositions for use in emulsion binders for nonwoven fabrics.
SUMMARY OF THE INVENTION
This invention provides formaldehyde-free monomers, emulsion copolymers formed with those monomers, and nonwoven fabrics bound by the emulsion copolymers. This invention also provides a process for the preparation of the monomer and a process for the preparation of the nonwoven fabric. The monomer is an N-allyl-N-dialkoxyethyl amine or amide, given the acronym NANDA, which can be copolymerized with one or more monoethylenically unsaturated comonomers to provide an emulsion binder for nonwoven fabrics. The fabrics bound with a binder formed from the NANDA monomer have comparable dry strength and solvent strength to fabrics formed with binder crosslinked with the N-methylolacrylamide, NMA.
DETAILED DESCRIPTION OF THE INVENTION
The N-allyl-N-dialkoxyethyl amide or amine monomers of the invention are represented by the formula: ##STR2## in which R 1 and R 2 are C 1 -C 3 alkyl; R 3 is hydrogen, C 1 -C 3 alkyl, or R 4 --C(O)--; and R 4 is C 1 -C 3 alkyl or C 6 -C 8 aryl. Preferably, R 1 and R 2 are independently methyl or ethyl and R 3 is CH 3 --C(O)--.
The monomer compounds of the invention are easily prepared through two routes utilizing readily available and inexpensive starting materials. In one route, an amino acetaldehyde acetal is reacted with allyl chloride under basic conditions to give an N-allyl-N-dialkoxyethyl amine, which is optionally further reacted with an acylating agent to give an N-allyl-N-dialkoxyethyl amide. Alternatively, a chloroacetaldehyde acetal is reacted under mildly basic conditions with an allyl amine to give an N-allyl-N-dialkoxyethyl amine, which is optionally further reacted with an acylating agent to give an N-allyl-N-dialkoxyethyl amide.
The acetals used as starting materials can be prepared by standard organic synthesis methods. For example, U.S. Pat. Nos. 4,642,389 and 4,642,390 issued to Neioel disclose methods of manufacture of acetals suitable for starting materials.
The reactions for the synthesis of the amine and amide monomers can be carried out neat or in any solvent suitable to the reactant compounds and product. If solvents are used, solvents suitable for the amine synthesis are polar solvents, preferably water or isopropanol, and solvents suitable for the amide synthesis are nonpolar solvents, preferably diethyl ether or toluene.
The resulting monomers are liquids stable at room temperature or at moderately elevated temperatures (<50° C.) without the need for the addition of inhibitors to prevent homopolymerization.
In another embodiment, the N-allyl-N-dialkoxyethyl amines or amides can be copolymerized with other monomers to form emulsion polymers suitable for use as binders, particularly binders for making nonwoven fabrics. Suitable comonomers for copolymerization with the NANDA monomers include vinyl acetate, acrylic acid, acrylamide, olefins (such as ethylene), vinyl halides (such as vinyl chloride), C 1 -C 8 alkyl acrylates or methacrylates, and mixtures of these comonomers.
The NANDA monomers are present in the copolymer in an amount from about 1% to about 10% by weight of the copolymer, and preferably from about 4% to about 6% by weight of the copolymer. The other copolymerizable monomers are present in the copolymer in an amount from about 90% to about 99% by weight of the copolymer, and preferably from about 94% to about 96% by weight of the copolymer.
Suitable monomer mixtures for copolymerization with the N-allyl-N-dialkoxyethyl amines or amides are a mixture of50%-90% vinyl acetate and 50%-10% ethylene by weight of the comonomer mixture, mixtures of 50%-90% vinyl acetate and 60%-10% acrylate esters by weight of the comonomer mixture, or mixtures solely of acrylate and methacrylate esters.
The copolymer may also contain an hydroxyl-containing comonomer as a coreactant for the NANDA monomer. The coreactant monomer may be present in an amount up to about 10% by weight of the comonomer mixture. The preferred hydroxyl-containing reactive comonomers are hydroxyethyl acrylate or hydroxypropyl acrylate and the corresponding methacrylates.
The polymerization of the NANDA monomers with the above mentioned comonomers is effected by conventional batch, semi-batch or continuous emulsion polymerization techniques well known in the art. Generally, the comonomers are polymerized in an aqueous medium (under pressures not exceeding 100 atmospheres if ethylene is employed) in the presence of an initiator and at least one emulsifying agent.
The polymerization is initiated by an effective amount of a free-radical initiator such as hydrogen peroxide, ammonium persulfate, sodium persulfate, potassium persulfate, or tert-butyl hydroperoxide, in amounts of between 0.01% and 3% by weight, preferably 0.01% and 1% by weight based on the total amount of the emulsion. The free radical initiators can be used alone or in combination with suitable reducing agents, such as ferrous salts, sodium dithionite, sodium metabisulfite, sodium thiosulfate and ascorbic acid to form a redox initiator system employed in amounts of 0.01% to 3%, preferably 0.01% to 1% by weight of the total emulsion. The initiators can be charged in the aqueous emulsifier solution or be added during the polymerization in doses.
The polymerization is carried out at a pH of between 2 and 7, preferably between 3 and 5. In order to maintain the pH range, it may be useful to work in the presence of customary buffer systems, for example, in the presence of alkali metal acetates, alkali metal carbonates, or alkali metal phosphates. Polymerization regulators, like mercaptan, aldehydes, chloroform, ethylene chloride and trichloroethylene, can also be added when needed.
The emulsifying agents used in the polymerization can be any of those generally known and used in emulsion polymerizations. Suitable emulsifying agents are anionic, cationic or nonionic emulsifiers or surfactants, or mixtures of them. Examples of suitable anionic emulsifiers are alkyl sulfonates, alkylaryl sulfonates, alkyl sulfates, sulfates of hydroxyalkanols, alkyl and alkylaryl disulfonates, sulfonated fatty acids, sulfates and phosphates of polyethoxylated alkanols and alkylphenols, and esters of sulfosuccinic acid. Examples of suitable cationic emulsifiers are alkyl quaternary ammonium salts and alkyl quaternary phosphonium salts. Examples of suitable nonionic emulsifiers are the addition products of 5 to 50 moles of ethylene oxide adducted to straight-chain and branched-chain alkanols with 6 to 22 carbon atoms, or alkylphenols, or higher fatty acids, or higher fatty acid amides, or primary and secondary higher alkylamines, and block copolymers of propylene oxide with ethylene oxide. Combinations of these emulsifying agents may also be used, in which case it is advantageous to use a relatively hydrophobic emulsifying agent Is in combination with a relatively hydrophilic agent. The amount of emulsifying agent is generally from about 1% to 10%, preferably from about 2% to 8%, by weight of the monomers used in the polymerization.
Various protective colloids may also be used in place of, or in addition to, the emulsifiers described above. Suitable colloids include partially acetylated polyvinyl alcohol (e.g., up to 50% acetylated), casein, hydroxyethyl starch, carboxymethyl cellulose, gum arabic, and the like, as known in the art of synthetic emulsion polymer technology. In general, these colloids are used at levels of 0.5% to 4% by weight of the total emulsion.
The emulsifier or protective colloid used in the polymerization can be added in its entirety to the initial charge to the polymerization zone, or a portion of the emulsifier, for example, from 25% to 90%, can be added continuously or intermittently during polymerization. The particle size of the emulsion can be regulated by the quantity of nonionic or anionic emulsifying agent or protective colloid employed. To obtain smaller particle sizes, greater amounts of emulsifying agents are used. As a general rule, the greater the amount of the emulsifying agent employed, the smaller the average particle size.
The polymerization reaction is generally continued until the residual monomer content is below about 1% of total emulsion mass. The completed reaction product is then allowed to cool to about room temperature, while sealed from the atmosphere.
The emulsions are produced and used at relatively high solids contents, for example, between 3s% and 70%, preferably not less than about 50%, although they may be diluted with water if desired.
When the emulsion polymers derived from the monomers of this invention are used as binders to prepare nonwoven fabrics, other additives conventionally employed in similar binders may be added to the emulsion. Examples of such additives are defoamers, pigments, catalysts, wetting agents, thickeners, and external plasticizers. The choice of additives and the amounts in which they are added are well known to those skilled in the art. These additives may be formulated into the emulsion binder if their stability in aqueous dispersion is high, or they may be added to the emulsion binder just before application if their stability in the emulsion is low.
Binders described above are suitably used to prepare nonwoven fabrics by a variety of methods known in the art. In another embodiment, this invention is directed to the nonwoven fabrics bonded with the emulsion polymers derived from the inventive monomers. In general, the nonwoven fabrics are formed from a loosely assembled web of fibers impregnated with the emulsion binder. Before the binder is applied to the web of fibers, it is mixed with a suitable catalyst to crosslink the emulsion binder to itself and to the fibers. After impregnation with the emulsion binder, the web of fibers is dried with heating, which serves to cure the binder. Suitable catalysts are known in the art, and can be, for example, hydrochloric acid, oxalic acid, citric acid, or salts such as ammonium chloride. The catalyst is generally present in an amount of about 0.5% to about 2% of the total polymer.
The starting fibrous web can be formed by any one of the conventional techniques, such as carding, garnetting, or air-laying, for depositing or arranging fibers in a web or mat. In general, the fibers extend in a plurality of diverse directions in general alignment with the major plane of the fabric, overlapping, intersecting and supporting one another to form an open, porous structure. Fibers that may be used in the starting web can be natural or synthetic fibers, such as natural and regenerated cellulose fibers (we define cellulose fibers to mean those that contain predominantly C 6 H 10 O 5 groupings), wool, cellulose acetate, polyamides, polyesters, acrylics, polyethylene, polyvinyl chloride, and polyurethanes, alone or in combination with one another.
The starting fibrous web preferably weighs from about 5 to about 65 grams per square yard and more preferably weighs from about 10 to about 40 grams per square yard. After formation, the starting fibrous web is subjected to one or more of the bonding operations used in the art to anchor the individual fibers together to form a self-sustaining web. The bonding operations widely used are overall impregnation, or imprinting the web with intermittent or continuous straight or wavy lines or areas of binder extending transversely or diagonally across the web, and if desired, also along the web.
The amount of binder, calculated on a dry basis, applied to the fibrous starting web ranges from about 10 to about 100 parts or more per 100 parts of the starting web, and preferably from about 20 to about 45 parts per 100 parts of the starting web.
After impregnation with binder, the web is dried, usually by passing it through an air oven or over sections of heated cans, and then cured, usually by passing it through a curing oven or over sections of hot cans. Ordinarily, convection air drying is effected at 65° to about 95° C. for 2-6 minutes, followed by curing at 145° to about 155° C. for 1-5 minutes. However, other time-temperature relationships can be employed, for example, shorter times at higher temperatures or longer times at lower temperatures, and these relationships are well known to one skilled in the art.
The following examples are given to illustrate the present invention, and are not to be construed to limit the scope and spirit of the invention.
EXAMPLES
EXAMPLE 1
Preparation of N-allyl-N-dimethoxyethyl Acetamide
Aminoacetaldehyde dimethyl acetal was reacted with allyl chloride to give N-allyl-N-dimethoxyethyl amine, which was then acetylated with acetyl chloride to give N-allyl-N-dimethoxyethylacetamide, according to the following reactions: ##STR3##
Aminoacetaldehyde dimethyl acetal (70.0 grams, 0.666 mole), allyl chloride (25.5 grams, 0.333 mole), and NaHCO 3 (42.0 grams, 2 moles), were added to 99% isopropanol (117.75 grams, approx. 115 ml) in a one liter pressure vessel, and heated approximately to 100° C. under 140 psi of pressure for six hours. The reaction mixture was cooled to room temperature and the contents filtered and washed with isopropanol under vacuum to remove the salt precipitate. The filtrate was concentrated on a rotary evaporator at 50° C. to remove the isopropanol and diluted with excess diethyl ether, 50-100 ml, to cause additional precipitation. The crystals were collected and the filtrate was again concentrated on a rotary evaporator at 50° C. to remove the ether and to give 43.5 grams of crude product. The crude product was distilled at reduced pressure and 16.8 grams of the product was isolated at 70°-72° C. The structure of the product, N-allyl-N-dimethoxyethyl amine, was confirmed by NMR.
N-allyl-N-dimethoxyethyl amine (16.0 grams, 0.11 mole) and triethylamine (11.1 grams) were added separately to the reaction flask with diethyl ether (100 ml, 70.7 grams), and cooled to about 5°-10° C. Acetyl chloride (8.7 grams, 0.11 mole) was added to the reaction flask over approximately 20 minutes while maintaining the temperature at less than 20° C. The reaction mixture was diluted with 150 ml of diethyl ether and held at room temperature for one hour. The reaction mixture was filtered to remove triethylamine hydrochloride. The solvent was removed by rotary evaporation to give 20.0 grams of liquid product, identified as N-allyl-N-dimethoxyethyl acetamide by NMR.
EXAMPLE 2
Alternate Route: Preparation of N-allyl-N-dimethoxyethyl Acetamide
Chloroacetaldehyde dimethyl acetal was reacted with allyl amine to give N-allyl-N-dimethoxyethyl amine, which was then acetylated with acetyl chloride to give N-allyl-N-dimethoxyethyl acetamide according to the following reactions: ##STR4##
Allylamine (708 grams, 12.17 moles) and chloroacetaldehyde dimethylacetal (440 grams, 3.5 moles) were charged to a 2 liter stainless steel autoclave and heated with agitation to 130° C. for 6.5 hours at 40 psig pressure. The reaction was cooled and 25% aqueous sodium hydroxide (560 grams, 3.5 moles) was added. Analysis by gas chromatography indicated 99.4% of the starting chloroacetaldehyde dimethyl acetal had reacted with the allyl amine. Bis(dimethoxyethyl) allyl amine accounted for about 4% of the products formed. The sodium chloride precipitate was filtered out and the remaining reaction mixture was distilled at atmospheric pressure through a 12 inch Vigreaux column. A fraction (889 grams) distilled from 100° C. to 120° C. was isolated and analyzed by gas chromatography as 98.6% N-allyl-N-dimethoxyethyl amine in 30% aqueous solution.
N-allyl-N-dimethoxyethyl amine (30% aqueous, 48.3 grams, 0.10 mole) was added to a glass reaction vessel fitted with a mechanical agitator. The agitator was started and sodium hydroxide (4.44 grams, 0.11 mole) was dissolved in the aqueous amine. Toluene (50 grams) was added and the mixture cooled to 0° to 5° C. Acetyl chloride (8.24 grams, 0.105 mole) was added over 10 minutes while maintaining the temperature below 5° C. The reaction mixture was stirred for 30 minutes at 5° C., agitation was stopped, and the mixture allowed to phase separate. The aqueous layer was discarded. Toluene was removed from the organic layer by rotary evaporation and 14.8 grams (0.08 mole) of N-allyl-N-dimethoxyethyl acetamide was isolated as confirmed by NMR.
EXAMPLES 3-5
Preparation of Emulsion Copolymers
Example 3 is an emulsion copolymer prepared with vinyl acetate and N-methylolacrylamide, and represents the industry standard. Examples 4 and 5 are emulsion copolymers prepared with the amide form of the NANDA monomer of the instant invention. TABLE I shows the composition in grams of Examples 3, 4, and 5, in which Example 3 is copolymer A, Example 4 is copolymer B, and Example 5 is copolymer C.
A two-liter four-necked flask was equipped with a stainless steel stirrer, condenser, addition funnel, nitrogen inlet, thermometer, and hot water bath. Initial-charge 1 was charged to the flask and purged with nitrogen. Initial-charge 2 was added to the reactor and the contents were heated to 78°-80° C. Five minutes after polymerization initiation was observed, Slow-add 1 (the monomer pre-emulsion mixture) and Slow-add 2 were added uniformly to the reactor over a four hour period. When Slow-add 1 and Slow-add 2 were completely added, the polymerization mixture was held for 45 minutes at 78°-80° C. and then cooled to room temperature. The emulsion polymer was then discharged.
EXAMPLES 6-11
The three copolymer compositions of Examples 3, 4, and 5, were each used to impregnate nonwoven fibrous webs of an air-laid wood pulp and of rayon. The resulting six examples were composed as follows:
Example 6: Pulp fibers impregnated with copolymer A.
Example 7: Pulp fibers impregnated with copolymer B.
Example 8: Pulp fibers impregnated with copolymer C.
Example 9: Rayon fibers impregnated with copolymer A.
Example 10: Rayon fibers impregnated with copolymer B.
Example 11: Rayon fibers impregnated with copolymer C.
TABLE I______________________________________Formula Material Ex.3/A Ex.4/B Ex.5/C______________________________________Initial-Charge 1 Distilled Water 349.1 396 396 Calsoft* 20% 1.0 1.0 1.0 Triton X305 70%** 3.0 3.0 3.0 Sodium Acetate 0.6 0.6 0.6 Ammonium Persulfate 0.8 0.8 0.8Initial-Charge 2 Vinyl Acetate 50 50 -- Butyl Acrylate 5 5 -- Ethyl Acrylate -- -- 35 Methyl Methacrylate -- -- 20Slow-Add 1 Distilled H.sub.2 O 90 90 90 Calsoft* 20% 10 10 10 Triton X305** 70% 6 6 6 Vinyl Acetate 325 325 -- Butyl Acrylate 120 120 -- Ethyl Acrylate -- -- 332 Methyl Methacrylate -- -- 113 N-Methylol 31.3 -- -- Acrylamide 48% NANDA*** 95% -- 29.2 29.2 Hydroxypropyl -- 19.3 19.3 AcrylateSlow-Add 2 Distilled Water 40 40 40 Ammonium Persulfate 1.0 1.0 1.0______________________________________ *A surfactant sold by Pilot Chemical Company **A surfactant sold by Union Carbide ***Nallyl-N-dimethoxyethyl acetamide
The individual fibrous webs were immersed in a 15% solids emulsion bath of copolymer of A, B, or C, corresponding to the examples as defined above, for approximately one minute. After removal from the bath, the webs were passed through nip rolls to remove excess emulsion to give samples containing 10% binder for pulp and 25% binder for rayon based on the weight of the starting fiber. The webs were dried on a canvas covered drier, and then cured in a forced air oven for two minutes at a temperature of 300° F. The webs were cut into strips 5 inches (12.7 cm) in machine direction and 1 inch (2.54 cm) in cross machine direction and evaluated for percent absorption of the copolymer (% pick up in weight over the basis weight), and for peak load and percent elongation when dry, wet with water, and wet with methyl ethyl ketone (MEK). Peak load and percent elongation are measures of tensile strength as tested on an Instron tensile tester Model 1130 equipped with an environmental chamber at crosshead speed of 10 cm/min. the gauge length at the start of each test was 3 inches (7.62 cm). The results of the tests are shown in TABLE II.
TABLE II______________________________________Example 6 7 8 9 10 11______________________________________Basis Weight* 10.6 11.1 10.4 23.6 25.2 25.3% Pick Up 36.8 37.3 37.3 21.4 18.4 17.9Dry Peak Load (lbs.) 6.31 5.57 5.37 2.39 1.47 1.11Dry % Elong. 5.8 6.1 6.1 11.1 10.8 11.3Wet Peak Load 2.57 2.09 2.33 0.98 0.44 0.46Wet % Elong. 10.2 10.4 10.1 25.8 28.9 27.7MEK** Peak Load 1.61 1.78 2.17 0.61 0.19 0.21MEK % Elong. 4.6 6.1 5.4 4.8 3.9 3.6______________________________________ *in grams per square yard **methyl ethyl ketone
Example 6 is pulp fiber impregnated with the industry standard emulsion polymer prepared with vinyl acetate and N-methylolacrylamide.
Example 7 is pulp fiber impregnated with an emulsion polymer prepared with NANDA and vinyl acetate.
Example 8 is pulp fiber impregnated with an emulsion polymer prepared with NANDA and acrylates.
Example 9 is rayon fiber impregnated with the industry standard emulsion polymer prepared with vinyl acetate and N-methylolacrylamide.
Example 10 is rayon fiber impregnated with an emulsion polymer prepared with NANDA and vinyl acetate.
Example 11 is rayon fiber impregnated with an emulsion polymer prepared with NANDA and acrylates.
The data in Table II show that the fibrous webs impregnated with the emulsion polymer formed from the NANDA monomer, which contains no formaldehyde, performed comparably on pulp and acceptably on rayon to the webs impregnated with the industry standard emulsion polymers formed with N-methylolacrylamide (NMA), which contain formaldehyde. Specifically, the NANDA containing emulsion polymers showed 85-88% of dry strength, 81-91% of wet strength, and 110-134% of solvent strength compared to the NMA containing lattices when used on air-laid wood pulp substrate, and 46-62% of dry strength, 45-47% of wet strength, and 31-34% of solvent strength compared to the NMA containing lattices when used on rayon substrate.
Various modifications and improvements on the above described examples will be apparent to those skilled in the art without departing from the spirit or scope of this invention. | A formaldehyde-free latent crosslinking monomer represented by the formula ##STR1## in which R 1 and R 2 are C 1 -C 3 alkyl; R 3 is hydrogen, C 1 -C 3 alkyl, or R 4 --C(O)--; and R 4 is C 1 -C 3 alkyl or C 6 -C 8 aryl, contains an allyl group capable of undergoing addition copolymerization and a dialkoxy ethyl group capable of crosslinking under acidic conditions. The monomer can be copolymerized with comonomers to form emulsion polymers for use as formaldehyde-free binders in nonwoven textiles. Methods for the preparation of the monomer, the polymers, and the nonwoven fabrics are described. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This is a divisional application of pending U.S. patent application Ser. No. 496,567, filed Aug. 12, 1974, now U.S. Pat. No. 3,938,413 by the same inventors.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a punch apparatus and more particularly to an apparatus for preparing elongated multiflanged extrusions for use in conjunction with fiberboard air handling ducts.
2. Description of the Prior Art
Air handling ducts of the type employed in heating and refrigeration systems have traditionally been formed of sheet metal, with a recently developed alternative being to form the ducts of insulative fiberboard. In many instances, the fiberboard ducts have an advantage over metal ducts due to such factors as weight, insulative properties, cost, and the labor involved.
However, fiberboard ducts have not achieved the acceptance they deserve due to the problems of assembling individual lengths of ducting and of interconnecting adjacent lengths thereof.
The fiberboard material employed in the air handling ducts is supplied in sheets, with the individual lengths of ducting being formed by longitudinally folding the sheet so that its opposite side edges are in contiguous abutting contact with each other and the resulting duct is either of square or rectangular cross sectional configuration. The abutting side edges of the fiberboard material are sealingly interconnected with tape, and the assembly of individual lengths of ducting into a complete duct system is accomplished in a similar manner by interconnecting adjacent lengths of the ducting with tape.
The use of tape as an assembly and closure material has, in many instances, been found to be unsatisfactory due to temperature, pressure and other factors causing the tape to lose its adhesive grip on the fiberboard material which, of course, will cause leakage of the duct system and in some cases can allow complete collapsing of the system.
Elongated multiflanged extrusions are now being employed in place of the above described tape for assembly and closure of the fiberboard ducts. Extrusions for this purpose are disclosed in U.S. Pat. No. 3,677,579, issued on July 18, 1972 to W. N. LaVanchy.
Briefly, a first type of extrusion, sometimes referred to as a longitudinal extrusion, is being employed for sealingly interconnecting the side edges of the fiberboard sheet to form the individual lengths of ducting.
Other configurations of extrusions, as determined by the type of interconnection desired, are being employed on the open ends of the individual ducts to facilitate interconnection of adjacent lengths of ducting. These latter extrusions may be referred to as joint extrusions.
Due to the great variations in lengths and cross sectional sizes of ducts, the above described extrusions are supplied in straight pieces which are individually prepared for installation and assembly when the specific sizes and configuration of the ducting are known.
Therefore, the longitudinal extrusions must be cut to the proper length and also must be provided with a recessed notch at each of their opposite ends to allow assembly of the joint extrusions to the fiberboard ducting.
The joint extrusions, which are also supplied in straight pieces, must be notched in specific locations along the length thereof to allow these extrusions to be bent into either the square or rectangular configuration suitable for mounting on the ends of the ducting. Also, the joint extrusions have a hanger flange which allows the assembled duct system to be suspendingly mounted therefrom. The hanger flange must be punched or otherwise provided with hanger holes at the proper locations.
Notching, cutting, and otherwise preparing the multiflanged extrusions for use with the fiberboard ducts is, in some instances, being accomplished with hand tools. Obviously, this is a very tedious, time consuming, and costly method, so a prior art apparatus for accomplishing these tasks was developed.
This prior art apparatus is a complex, slow operating and inadequately designed machine which has achieved only limited acceptance for those reasons as well as the cost which has placed this apparatus beyond the economic justification of many companies doing this sort of work.
Therefore, a need exists for a new and improved extrusion preparation apparatus which overcomes some of the problems of the prior art.
SUMMARY OF THE INVENTION
The multiflanged extrusion preparation apparatus of the present invention includes an input channel and an output channel aligningly positioned on opposite sides of the workpiece supporting plate of a suitable punch press. These channels serve as a feeding means by which the extrusion workpieces are fed through and punched by one of two interchangeable die sets, with the particular die set being determined by the type of extrusion being processed.
Each of the die sets are demountably attachable to the work piece supporting plate of the punch press, and each includes a fixed bottom pedestal and a movable top plate. The fixed pedestal of each of the die sets includes a fixture die means especially designed to slidingly receive the extrusion and to supportingly position the extrusion for the punching operation. The top plate of each of the die sections is reciprocally movable toward the pedestal by means of the punch press and includes the cutting die means which is especially designed to punch the extrusion as required.
Accordingly, it is an object of the present invention to provide a new and improved extrusion preparation apparatus.
Another object of the present invention is to provide a new and improved extrusion preparation apparatus which is economical to manufacture and efficient to operate.
Another object of the present invention is to provide a new and improved extrusion preparation apparatus which prepares elongated multiflanged extrusions for use in assembling and installing air handling ducts of the type fabricated of insulative fiberboard.
Another object of the present invention is to provide a new and improved extrusion preparation apparatus which employs exchangeable die sets for preparing various types of elongated multiflanged extrusions for use in assembling and installing fiberboard air handling ducts.
The foregoing and other objects of the present invention, as well as the invention itself, will be more fully understood from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the multiflanged extrusion preparation apparatus of the present invention which illustrates the various features thereof.
FIG. 2 is a fragmentary perspective view of one type of multiflanged extrusion after having been processed by the apparatus of the present invention.
FIG. 3 is a fragmentary perspective view of another type of multiflanged extrusion after having been processed by the apparatus of the present invention.
FIG. 4 is a fragmentary perspective view of still another type of multiflanged extrusion after having been processed by the apparatus of the present invention.
FIG. 5 is a front elevational view of one of the die sets employed in the apparatus of the present invention.
FIG. 6 is a side elevational view of the die set shown in FIG. 5.
FIG. 7 is a sectional view taken on the line 7--7 of FIG. 5.
FIG. 8 is a sectional view taken on the line 8--8 of FIG. 6.
FIG. 9 is a front elevational view of another one of the die sets employed in the apparatus of the present invention.
FIG. 10 is a side elevational view of the die set shown in FIG. 9.
FIG. 11 is a sectional view taken on the line 11--11 of FIG. 9.
FIG. 12 is a sectional view taken on the line 12--12 of FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings, FIG. 1 illustrates the multiflanged extrusion preparation apparatus of the present invention which is indicated generally by the reference numeral 10. The apparatus 10 is shown to include an input channel 11 and an output channel 12 which are aligningly positioned on opposite side edges of a support plate 13. The support plate 13 may be a free standing structure as shown, or may be formed integral with a suitable punch press 14. In either instance, the support plate 13 serves as a carrying means for a die set 15. The die set 15 is one of an interchangeable pair of die sets 15 and 16, with the die set 15 being shown in FIGS. 1, and 5 through 8, and the die set 16 being shown in FIGS. 9 through 12. The die sets 15 and 16 are demountably attachable to the support plate 13 and are suitably coupled to the punch press 14 for reciprocal operation thereby as will hereinafter be described in detail.
It is believed that a more thorough understanding of the objects and operation of the apparatus 10 of the present invention will be achieved if the design and purposes of the various types of multiflanged extrusions or workpieces, are known. Therefore, FIGS. 2 and 3 show extrusions 17 and 18, respectively, which are of the type referred to as joint extrusions, and FIG. 4 shows a longitudinal extrusion 19.
The multiflanged extrusion 17, shown in FIG. 2, is a U-shaped in cross section elongated member having an inner flange 20, an outer flange 21 and an interconnecting surface 22 which extends beyond the outer flange 21 to form a hanger flane 23. The inner flange 20, outer flange 21 and interconnecting surface 22 define an open channel 24 for receiving the edge of fiberboard ducting material (not shown). This edge of the ducting material (not shown) is formed either into a square or rectangular end configuration of the duct and thus, the extrusion 17 must be bent at various points along its length to conform to this end configuration. Bending of the extrusion 17 requires that a portion, between points A and B of the inner flange 20, be removed, a V-shaped notch 25 be formed in the interconnecting surface 22, and that a V-shaped notch 26 be formed in the hanger flange 23. It will be noted that the outer flange 21 is left intact so that complete severing of the extrusion will not occur. After removal of the portion between points A and B and forming of the notches 25 and 26, the extrusions 17 can be bent into the dashed line position shown in FIG. 2 to form a square corner.
The extrusion 18 shown in FIG. 3 is H-shaped in cross section and has an inner flange 27, an outer flange 28 and a midpoint interconnecting surface 29 which is coplanar with a hanger flange 30 extending from the midpoint of the outer flange 28. The H-shaped configuration of the extrusion 18 defines back to back open channels 31 for receiving the open end edges (not shown) of two adjacent fiberboard ducting members (not shown). Thus, as was required with the extrusion 17, the extrusion 18 must be bent to conform to the end configuration of the lengths of ducting (not shown). To accomplish this bending of the extrusion 18, the portion between points C and D of the inner flange 27 must be removed, and V-shaped notches 33 and 34 must be formed in the interconnecting surface 29 and the hanger flange 30, respectively. As was the case with regard to the extrusion 17, the outer flange 28 of the extrusion 18 is left intact, and the extrusion 18 is bent into the dashed line position to form a square corner.
It will be seen that both of the extrusions 17 and 18 are provided with oval shaped apertures 32 formed through their respective hanger flanges 23 and 30. These apertures 32 are employed for installation purposes of the assembled ducting system (not shown) and may be formed simultaneously with the above described extrusion preparation.
The longitudinal extrusion 19, as shown in FIG. 4, has a main angle member 35 with a secondary angle member 36 extending from one of the legs of the member 35. These angle members 35 and 36 are configured to define a pair of channels 37 and 38 which are adapted to receive the opposite side edges of a sheet of insulative fiberboard material (not shown) when that material is shaped to form a length of air handling duct (not shown). The extrusion 19 is supplied in elongated straight pieces and must be cut to the proper length and also must be notched at its opposite ends to allow mounting of the joint extrusions 17 or 18 on the ends of the duct (not shown). Thus, preparation of the extrusion 19 requires severing of the extrusion into predetermined lengths and requires that the secondary angle member 36 be formed with a notch 39 by removing the amount thereof which is shown in dashed lines in FIG. 4.
Referring now to FIGS. 5 through 8 wherein the die set 15 is shown as being mounted on the support plate 13, and as shown in FIG. 5 is aligningly disposed between the discharge end 40 of the input channel 11, and the receiving end 41 of the output channel 12.
The die set 15 includes a fixed pedestal 44 having a pair of vertical rods 45 extending therefrom. The rods 45 serve as supporting guideways for a movable top plate 46 which is slidably journaled on the rods for reciprocal movement toward and away from the pedestal 44, as will hereinafter be described. The pedestal 44 also has a matrix or fixture die means 48 mounted thereon which guides movement of the workpieces into a predetermined path through the die set 15 and supports these workpieces for the punching operation as will hereinafter be described.
The fixture die means 48, as seen best in FIG. 8, includes a pair of support dies 49 and 50 and a backup die 51. The support dies 49 and 50 are mounted adjacent to the front edge 52 of the pedestal 44 and are spaced apart with respect to each other to provide a gap 53 therebetween. Each of the supporting dies 49 and 50 are provided with a rearwardly disposed portion 54 of their upper surface and a forwardly disposed portion 55 thereof which are separated by a horizontally extending vertical channel 56 formed in the dies 49 and 50. The forward portion 55 of each of the dies 49 and 50 is also formed with a vertically extending oval shaped aperture 57 therein. The backup die 51 is mounted on the pedestal 44 so as to be rearwardly disposed from the support dies 49 and 50 to provide a horizontally extending vertical passage 58 therebetween. The backup die 51 is also provided with a vertically extending channel 59 intermediate its ends which is aligned with the gap 53 between the support dies 49 and 50.
To facilitate understanding of the movement guiding and supporting functions of the fixture die means 48, the positioning of the extrusion 18 therein will now be described. The horizontally extending vertical passage 58, between the support dies 49 and 50 and the backup die 51, is adapted to receive the inner flange 27 of the extrusion 18 which is oriented so that the midpoint interconnecting surface 29 rests on the rearwardly disposed portions 54 of the support dies 49 and 50. The hanger flange 30 of the extrusion 18 will rest on the forwardly disposed portions 55 of the dies 49 and 50, and the outer flange 28 of the extrusion 18 is received in the horizontally extending vertical channels 56 formed in the dies 49 and 50. It should be understood that the above described positioning of the extrusion 18 within the fixture die means 48 also applies to the extrusion 17, as either of these extrusions can be prepared for assembly and installation within the die set 15. Thus, it may now be seen that the fixture die means 48 provides a horizontally extending workpiece supporting and movement path which is transverse to the gap 53 and channel 59 thereof.
A spring loaded roller mechanism 60 is provided at the workpiece input end of the fixture die means 48 and another spring loaded roller mechanism 61 is located at the workpiece output end of the fixture die means. The roller mechanisms 60 and 61 are mounted on the pedestal 44 and are disposed so that the rollers 62 thereof are biased, by suitable springs 63 (one shown in FIG. 6), toward the backup die 51. These mechanisms 60 and 61 are employed to load the workpiece into sliding engagement with the backup die 51 which is accomplished by the rollers 62 bearing on the lower edge of the inner flange 27 of the extrusion 18 or the lower edge of the inner flange 20 of the extrusion 17.
As seen best in FIG. 8 a U-shaped stripper 64 is provided on the backup die 51, and that stripper is disposed so as to conform to and overlay the vertically extending channel 59 formed in the backup die. The stripper 64 is provided with extending ends 65 which protrude laterally from the backup die 51 over the passage 58 between the backup die 51 and the support dies 49 and 50. The extending ends 65 of the stripper 64 prevent upward movement of the workpiece as will become apparent as the description progresses.
Each of the support dies 49 and 50 have a stripper 67 mounted thereon, and these strippers 67 each have a cantilevered bar 68 which extends proximate the apertures 57 formed in the support dies 49 and 50 and also extend toward the gap 53 between these dies. The strippers 67 also serve to prevent upward movement of the workpiece as will become apparent as the description progresses.
As hereinbefore mentioned, the top plate 46 of the die set 15 is reciprocally movable on the vertical guide rods 45, and this movement is provided by a punch press mechanism 14. It should be apparent that various types of punch presses could be employed; however, it is preferred that an electric clutch operated flywheel type of press be employed.
The top plate 46 is provided with a boss 70 extending upwardly therefrom to which the punch press 14 is suitably coupled, and the plate 46 has cutting die means 72 depending from the downwardly facing surface thereof, so that the cutting die means 72 will be reciprocally movable in a path which transversely intersects the workpiece supporting and movement path formed in the fixture die means 48.
As best seen in FIGS. 6 and 7, the cutting die means 72 includes a first cutting die 73 which is mounted adjacent the front edge 74 of the plate 46, and a second cutting die 75 that is spaced rearwardly from the first cutting die 73 to provide a recess 76 therebetween. The die means 72 also includes a pair of oval shaped punches 77, each positioned adjacent an opposite side of the first cutting die 73.
The first cutting die 73 has a pair of vertically extending angularly disposed surfaces 78 in a V-shaped configuration. This first cutting die 73 is positioned in vertical alignment with the forward portion of the gap 53 provided between the support dies 49 and 50 of the fixture die means 48. Thus, downward movement of the plate 46 will move the first cutting die 73 into the forward portion of the gap 53, and this movement will punch out the V-shaped notch 26 in the hanger flange 23 of the extrusion 17, or the V-shaped notch 34 of the hanger flange 30 of extrusion 18 depending on which of these extrusions is positioned within the die set 15.
The second cutting die 75 is also provided with a pair of vertically extending surfaces 80 which are angularly disposed to form a V-shaped configuration. This second cutting die 75 is positioned in vertical alignment with the rearwardly disposed portion of the gap 53 between the support dies 49 and 50 and also aligns with the vertically extending channel 59 formed in the backup die 51. Thus, upon downward movement of the plate 46, the second cutting die 75 will move into the rear portion of the gap 53 and the channel 59 of the backup die 51. It will be noted that when the second cutting die 75 moves downwardly as described above, it will also move into the passage 58 between the support dies 49 and 50 and the backup die 51. Therefore, when the extrusion 17 is positioned within the die set 15, the second cutting die 75 will punch the V-shaped notch 25 in the interconnecting surface 22 of the extrusion 17, and also will remove the portion of material between the points A and B of the inner flange 20. Likewise, when the extrusion 18 is positioned within the die set 15, downward movement of the second cutting die 75 will punch the V-shaped notch 33 in the midpoint interconnecting surface 29, and will remove the material between the points C and D of the inner flange 27.
As hereinbefore described, the first and second cutting dies 73 and 75, respectively, are spaced apart with respect to each other to provide the recess 76 therebetween. This recess 76 is in alignment with the channel 56 formed in the supporting dies 49 and 50 so that when extrusion 17 is positioned in the die set 15, its outer flange 21, which is positioned in the channel 56 will not be touched by either of the cutting dies 73 or 75. Also, the extrusion 18 is positioned in the die set 15, the outer flange 28 thereof will be left intact. The recess 76 is somewhat larger than the thickness of the outer flanges 21 and 28, respectively, of the extrusions 17 and 18, thus a protruding lip (not shown) portion of the interconnecting surfaces 22 and 29, respectively, will remain. The second cutting die 75 is provided with a protrusion 82 which notches the protruding lip (not shown) so that uniform bending of the extrusions 17 and 18 will be possible.
The oval shaped punches 77 of the cutting die means 72 are in vertical alignment with the vertically extending apertures 57 formed in the front portions 55 of the supporting dies 49 and 50. These punches 77 will move into and out of the apertures 57 upon reciprocal movement of the top plate 46, and thus may be seen to be employed to punch the oval mounting apertures 32 in the hanger flanges 23 and 30 of the extrusions 17 and 18, respectively, as determined by which of these extrusions is positioned in the die set 15.
Referring now to FIGS. 9 through 12 wherein the die set 16 is shown as being mounted on the support plate 13, and as shown in FIG. 9 is aligningly disposed between the discharge end 40 of the input channel 11, and the receiving end 41 of the output channel 12.
The die set 16 includes a fixed pedestal 84 having a pair of vertical rods 85 extending therefrom. The rods 85 act as supporting guideways for a movable top plate 86 which is slidably journaled on the rods for reciprocal movement toward and away from the pedestal 84. The pedestal 84 also has a matrix or fixture die means 88 mounted thereon which guides lateral movement of the workpieces into a predetermined path through the die set 16, and supports the workpieces for the punching operation as will hereinafter be described.
The fixture die means 88, as seen best in FIG. 12 includes a pair of supporting dies 89 and 90, and a backup die 91. The support dies 89 and 90 are mounted adjacent to the front edge 92 of the pedestal 84 and the backup die 91 is disposed rearwardly therefrom. The support dies 89 and 90 are spaced apart with respect to each other at their upper ends to provide a gap 93 therebetween. Each of the supporting dies 89 and 90 are formed with a base plate 94 which is directly mounted on the pedestal 84, an intermediate block 95 having a rearwardly extending cantilevered end 96, with the intermediate block 95 being mounted on the base plate 94, and an upper block 97 mounted atop the intermediate block 95. As seen best in FIGS. 10 and 12, the base plate 94 of each of the support dies 89 and 90 extends rearwardly from the front edge 92 of the pedestal 84 into engagement with the backup die 91. The intermediate blocks 95 extend rearwardly in the same manner but terminate just short of coming into contact with the backup die 91 to provide a horizontally extending vertical passage 98 between the cantilevered end 96 of the intermediate block 95 and the backup die 91. The intermediate block 95 is also recessed on its bottom surface to form a horizontally extending horizontal passage 99 between the cantilevered end 96 of the intermediate block 95 and the upper surface of the base plate 94. The vertical passage 98 and the horizontal passage 99 intersect and are normal to each other. The upper block 97 extends rearwardly from the front edge 92 of the pedestal 84 and terminates just short of the cantilevered end 96 of the intermediate block 95, thus providing horizontally extending enlarged passage 100 between the upper block 97 and the backup die 91. The base plates 94 of the supporting dies 89 and 90 are separated from each other by slot 101 which extends from the front edge 92 of the pedestal 84, and a slot 103 in the backup die 91 is in alignment therewith. An elongated aperture 102 is formed in the pedestal 84, and this aperture 102 is vertically aligned with the slots 101 and 103. The aperture 102 is provided so that metal cut from the workpiece can drop through this aperture 102.
To facilitate understanding of the movement guiding and supporting functions of the fixture die means 88, positioning of the extrusion 19 therein will now be described. The vertical passage 98 between the cantilevered end 96 of the intermediate block 95 and the backup die 91, and the horizontal passage 99, between the cantilevered end 96 of the intermediate block 95 and the upper surface of the base plate 94, are adapted to slidingly receive the main angle member 35 of the extrusion 19. The main angle member 35 will extend upwardly through the vertical passage 98 into the enlarged passage 100 so that the secondary angle member 36 of the extrusion is disposed within the enlarged passage 100 with one leg of the secondary angle member 36 resting on the upper surface of the intermediate block 95 and the other leg bearing on the rearwardly disposed end of the upper block 97. Thus, the movement of the workpiece is transverse with respect to the gap 93 and slot 101 of the support dies 89 and 90 and is transverse to the slot 103 of the backup die 91.
The top plate 86 is provided with a boss 104 extending upwardly therefrom to which the punch press 14 is suitably coupled for providing the reciprocal movement of the top plate. The top plate 86 is provided with a cutting die means 106 depending from the downwardly facing surface thereof.
The cutting die means 106 is formed with a blade die 107 which is in vertical alignment with the slots 101 and 103 formed between the supporting dies 89 and 90 and between the backup die 91. Thus, downward movement of the top plate 86 will move the blade die 107 downwardly through the enlarged passage 100, through the vertical passage 98, and through the horizontal passage 99 into the slots 101 and 103, and will therefore sever the main angle member 36 of the extrusion 19 when that extrusion is positioned in the fixture die means 88.
The cutting die means 106 also includes a pair of wedge shaped dies 108 and 109 which are preferrably integral with the blade die 107 and are positioned on opposite sides thereof. Each of the wedge dies 108 and 109 are formed with a leading cutting edge 110 which is upwardly and laterally offset from the leading cutting edge 111 of the blade die 107.
The wedge dies 108 and 109 are in vertical alignment with the gap 93 provided between the support dies 89 and 90 of the fixture die means 88 so that downward movement of the top plate 86 will move the wedge dies 108 and 109 downwardly into the gap 93. The above described offset relationship of the wedge dies 108 and 109 with respect to the blade die 107 is critical so that downward movement of the cutting die means 106 will not bring the wedge dies into an intersecting relationship with the laterally extending paths of the vertical passage 98, the horizontal passage 99 or the rearwardly disposed portion of the enlarged passage 100. Therefore, when the extrusion 19 is positioned within the fixture die means 88, the main angle member 35 thereof will not be touched by the wedge dies 108 and 109 upon downward movement thereof, and these wedge dies will come into cutting contact only with that portion of the secondary angle memeber which is disposed within the gap 93.
Thus, operation of the die set 16 can now easily be seen to sever the extrusion 19, into what may be defined as an outgoing length (not shown) and an incoming length (not shown), and simultaneously form a notch 39 in the secondary angle member 36 of the adjacent ends of the outgoing length and the incoming length.
While the principles of the invention have now been made clear in an illustrated embodiment, there will be immediately obvious to those skilled in the art, many modifications of structure, arrangements, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted for specific environments and operation requirements without departing from those principles. The appended claims are therefore intended to cover and embrace any such modifications within the limits only of the true spirit and scope of the invention. | Multiflanged extrusion preparation apparatus including means by which multiflanged elongated extrusions are aligningly fed to punch press operated dies which notch, trim, and otherwise prepare the extrusions for use in assembling and installing of fiberboard air handling ducts. | 1 |
This application claims priority as a divisional application of U.S. patent application Ser. No. 12/136,858, filed Jun. 11, 2008. The disclosure of the priority application is incorporated by reference herein in its entirety.
BACKGROUND
1. Technical Field
This disclosure relates generally to oil and gas well logging, and more specifically to directional resistivity measurements using a transmitter/receiver pair whereby there is relative rotation between the transmitter and receiver antennas. A method is disclosed for mathematically extracting some or all of the nine components of the electromagnetic coupling tensor for a formation and the distances to bed boundaries using the transmitter/receiver pair described herein.
2. Description of the Related Art
An alternative to wireline logging techniques is the collection of data on downhole conditions during the drilling process. By collecting and processing such information during the drilling process, the driller can modify or correct key steps of the operation to optimize performance. Schemes for collecting data of downhole conditions and movement of the drilling assembly during the drilling operation are known as measurement-while-drilling (“MWD”). Similar techniques focusing more on measurement of formation parameters than on movement of the drilling assembly are known as logging-while-drilling (“LWD”). However, the terms MWD and LWD are often used interchangeably, and the use of either term in this disclosure will be understood to include both the collection of formation and borehole information, as well as data on movement and placement of the drilling assembly. The term “parameter”, as used herein, includes, but is not limited to, formation properties, dip and azimuth of bed boundaries, distances to bed boundaries, as well as data on movement and placement of the drilling assembly. Formation “properties” include, for example, vertical resisitvity, horizontal resistivity, the conductivity tensor, the dielectric permittivity, porosity, and saturation. MWD tools are available to guide drill strings and therefore the resulting boreholes into more productive reservoir zones. MWD tools used for this purpose typically have been propagation resistivity tools, also known as array compensated resistivity (ARC) tools, with a 360° measurement and deep imaging capability to detect fluid contacts and formation changes up to 15 feet from the borehole. Measurements are commonly made of the phase-shift and attenuation of the signals at the receiver coils, which are indicative of the rock conductivity.
Currently available ARC tools are non-azimuthal and utilize two receivers that compensate for any electronic drift associated with the transmitter. The electronic drift associated with the two receivers and any imbalance between the two receivers is removed using a scheme called borehole compensation, which involves the use of a second transmitter, symmetrically placed with respect to the first transmitter. The transmitters are alternately energized so two phase difference signals can be measured when the two transmitter coils operate at identical frequencies. However, alternately using two transmitter coils slows the rate of data acquisition, which can lead to errors due to the time delay between sequential measurements. Further, use of multiple transmitters may require the signals to be time-multiplexed when operating at the same frequency to avoid cross-talk. Multiplexing slows the rate of data acquisition. The errors due to time delays are magnified when drilling rates (rate of penetration) are high.
As an improvement to the ARC tools, tools were developed that incorporate tilted receiver antennas in the drill collar. The non-axial antennae obtain directional electromagnetic measurements that are used to determine distance and azimuthal orientation of formation boundaries in any type of mud. These measurements are transmitted uphole and are displayed on a graphical interface to provide information on distance to boundaries, formation resistivity and orientation. This information is critical in low resistivity pay zones and in laminated formations because accurate identification and characterization of hydrocarbon reserves is not possible without knowing the resistivity anisotropy. Further, using a transmitter/receiver pair in which one of the antennae is tilted or non-axial, a ratio of any two measurements at two different azimuthal angles can be used to remove the electronic drift of both the transmitter and receiver.
However, if the resistivity anisotropy of the formation is to be completely understood, values for all nine components of the electromagnetic coupling tensor need to be obtained. For example, a complex conductivity matrix can be expressed as
α apparent = ( σ xx σ xy σ xz σ yx σ yy σ zx σ zx σ zy σ zz )
which can be inverted for horizontal resistivity, vertical resistivity, dip angle and azimuth assuming a dipping layered earth model.
Further, methods for extracting all nine components (XX XY, XZ YX, YY, YZ, ZX ZY, ZZ) of the electromagnetic tensor are available for tri-axial wireline tools that are commonly referred to as tri-axial measurements. This method preferably uses three collocated transmitters and three collocated receivers with orientations in the x, y and z directions wherein the z direction is along the tool axis or coaxial with the tool. Measurements with different transmitter/receiver (T/R) combinations that are corrected for antenna magnetic dipoles yield the nine coupling tensor components directly. Obviously, the use of three transmitters and three receivers (i.e., six antennas) presents data acquisition and gain correction problems.
Returning to MWD and LWD tools, Schlumberger's PERISCOPE™ tool uses tilted and axial antennas and the rotation of the tool or drill string to obtain the five non-zero components when in planar or “layer cake” formations using a fitting algorithm performed on harmonic behavior of the measurement with respect to the tool face. A tool having three transmitters with different azimuthal orientations and a tilted receiver can, in combination with tool rotation, obtain all nine components of the electromagnetic coupling tensor.
Therefore, using current technology, determination of all nine couplings (XX XY, XZ, YX, YY, YZ, ZX, ZY, ZZ) of a formation electromagnetic coupling tensor requires a minimum of four antennas (one tilted antenna and three possibly collocated antennas) combined with the tool rotation. The relative gain of each antenna pair needs to be either measured or estimated from the data. Also, the azimuthal angle of all respective antenna combinations must be measured and considered constant, which may detract from the accuracy of the calculations.
Therefore, there is a need for a tool and method that provide for a more simplified extraction of all nine components of the electromagnetic coupling tensor which avoids the use of multiple transmitters and receivers and the inherent disadvantages associated with multiple transmitter/receiver use.
SUMMARY OF THE DISCLOSURE
A logging tool and method to make subsurface measurements is disclosed, wherein the tool is placed within a borehole penetrating a formation. The tool has a transmitter antenna and a receiver antenna spaced apart along a longitudinal axis of the tool, and at least one of the transmitter or receiver antennas has a dipole moment that is non-coaxial with the longitudinal axis of the tool. The at least one non-coaxial antenna can rotate relative to the other antenna. Energy is transmitted from the transmitter antenna and a signal associated with the transmitted energy is measured at the receiver antenna while the at least one non-coaxial antenna rotates relative to the other antenna
Other advantages and features will be apparent from the following detailed description when read in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the disclosed methods and apparatuses, reference should be made to the embodiment illustrated in greater detail on the accompanying drawings, wherein:
FIG. 1 illustrates, partially in schematic and block form, a wellsite system in which the disclosed tools and methods can be employed.
FIG. 2 is a partial schematic view of a deep imaging resistivity tool and motor which can be used to practice the disclosed methods and techniques.
FIG. 3 diagrammatically illustrates a two antenna apparatus wherein both the receiver antenna, shown at the left, and the transmitter antenna, shown at the right, are tilted at an angle β with respect to the tool axis z, the receiver is rotating at an angle φ with respect to the vertical axis x and α is the azimuthal angle difference between the receiver and transmitter antennas.
FIGS. 4A-4G illustrate different receiver/transmitter pairs wherein the antennas disposed to the right in FIGS. 4A-4G rotate with respect to the antennas disposed to the left.
FIG. 5 is a flow chart showing one embodiment of the method, in accordance with the present invention.
It should be understood that the drawings are not to scale and that the disclosed embodiments are sometimes illustrated diagrammatically and in partial views. In certain instances, details that are not necessary for an understanding of the disclosed methods and apparatuses or that render other details difficult to perceive may have been omitted. It should be understood, of course, that this disclosure is not limited to the particular embodiments illustrated herein.
DETAILED DESCRIPTION
The tools and methods disclosed herein are applicable to wireline or LWI) tools that contain directional antennas to determine all or some of the electromagnetic coupling tensor components of a formation. The components may be used for well placement applications and/or formation evaluation. For example, the components may be passed to an inversion routine to determine the distances to bed boundaries, anisotropic resistivities, dip, and azimuth of the formation. Distances to bed boundaries, for example, may aid in deciding drilling directions.
For background purposes, FIG. 1 illustrates a wellsite system in which the disclosed methods can be employed. The wellsite can be onshore or offshore. In this exemplary system, a borehole 11 is formed in subsurface formations by rotary drilling in a manner that is well known. Directional drilling can also be used.
A drill string 12 is suspended within the borehole 11 and has a bottom hole assembly (BHA) 100 which includes a drill bit 105 at its lower end. The surface system includes platform and derrick assembly 10 positioned over the borehole 11 and the assembly 10 includes a rotary table 16 , kelly 17 , hook 18 and rotary swivel 19 . The drill string 12 is rotated by the rotary table 16 , energized by means not shown, which engages the kelly 17 at the upper end of the drill string 12 . The drill string 12 is suspended from a hook 18 , attached to a traveling block (also not shown), passes through the kelly 17 , and the rotary swivel 19 permits rotation of the drill string 12 relative to the hook 18 . As is well known, a top drive system could alternatively be used.
The surface system of FIG. 1 further includes drilling fluid or mud 26 stored in a pit 27 formed at the well site. A pump 29 delivers the drilling fluid 26 to the interior of the drill string 12 via a port in the swivel 19 , causing the drilling fluid 26 to flow downwardly through the drill string 12 as indicated by the directional arrow 8 . The drilling fluid 26 exits the drill string 12 via ports in the drill bit 105 , and then circulates upwardly through the annulus region between the outside of the drill string 12 and the wall 13 of the borehole 11 , as indicated by the directional arrows 9 . In this known manner, the drilling fluid 26 lubricates the drill bit 105 and carries formation cuttings up to the surface, or the cuttings are removed from the drilling fluid 26 before it is returned to the pit 27 for recirculation.
The bottom hole assembly 100 includes a logging-while-drilling (LWD) module 120 , a measuring-while-drilling (MWD) module 130 , a roto-steerable system and motor 150 , and drill bit 105 . The LWD module 120 is housed in a special type of drill collar, as is known in the art, and can contain one or a plurality of known types of logging tools. It will also be understood that more than one LWD and/or MWD module can be employed, e.g., as represented at 120 A. References, throughout, to a module at the position of 120 can alternatively mean a module at the position of 120 A as well. The LWD module 120 includes capabilities for measuring, processing, and storing information, as well as for communicating with the surface equipment. The LWD module 120 includes a directional resistivity measuring device, such as one of the Schlumberger PERISCOPE™ directional deep imaging 360° resistivity tools.
The MWD module 130 is also housed in a type of drill collar, as is known in the art, and can contain one or more devices for measuring characteristics of the drill string and drill bit. The MWD tool 130 further includes an apparatus (not shown) for generating electrical power to the downhole system, such as a mud turbine generator powered by the flow of the drilling fluid. Other power and/or battery systems may be employed. The MWD module 130 may include one or more of the following types of measuring devices: a weight-on-bit measuring device, a torque measuring device, a vibration measuring device, a shock measuring device, a stick slip measuring device, a direction measuring device, and an inclination measuring device.
In the system of FIG. 1 , a drill string telemetry system is employed which, in the illustrated embodiment, comprises a system of inductively coupled wired drill pipes 180 that extend from a surface sub 185 to an interface sub 110 in the bottom hole assembly 100 . Depending on factors including the length of the drill string, relay subs or repeaters can be provided at intervals in the string of wired drill pipes, an example being shown at 182 . The interface sub 110 provides an interface between the communications circuitry of the LWD and MWD modules 120 , 130 and the drill string telemetry system which, in this embodiment, comprises wired drill pipes with inductive couplers 180 . The wired drill pipes 180 can be coupled with an electronics subsystem 30 that rotates with kelly 17 and includes a transceiver and antenna that communicate bidirectionally with the antenna and transceiver of logging and control unit 4 , which includes the uphole processor subsystem. In FIG. 1 , a communication link 175 is schematically depicted between the electronics subsystem 30 and antenna 5 of the logging and control unit 4 . Accordingly, the configuration of FIG. 1 provides a communication link from the logging and control unit 4 through communication link 175 , to surface sub 185 , through the wired drill pipe telemetry system, to downhole interface 110 and the other components of the bottom hole assembly 100 and, also, the reverse thereof, for bidirectional operation.
While only one logging and control unit 4 at one wellsite is shown, one or more surface units across one or more wellsites may be provided. The surface units may be linked to one or more surface interfaces using a wired or wireless connection via one or more communication lines. The communication topology between the surface interface and the surface system can be point-to-point, point-to-multipoint or multipoint-to-point. The wired connection includes the use of any type of cables or wires using any type of protocols (serial, Ethernet, etc.) and optical fibers. The wireless technology can be any kind of standard wireless communication technology, such as IEEE 802.11 specification, Bluetooth, zigbee or any non-standard RF or optical communication technology using any kind of modulation scheme, such as FM, AM, PM, FSK, QAM, DMT, OFDM, etc. in combination with any kind of data multiplexing technologies such as TDMA, FDMA, CDMA, etc.
FIG. 2 is a simplified schematic view of a directional deep-reading logging-while-drilling tool 121 , as part of the LWD tool or tools 120 shown in FIG. 1 . The tool 121 includes at least two antennas 122 , 123 that, in the example shown in FIG. 2 , are tilted with respect to the tool axis 124 . The arrows shown as figure elements 122 and 123 in FIGS. 2 , 3 , and 4 A- 4 F represent the electric or magnetic dipole moments of the antennas. As shown in FIGS. 4A-4F below, the antennas 122 , 123 may be tilted, transverse, or coaxial with the tool axis 124 . Returning to FIG. 2 , the antennas 122 , 123 in this example are tilted at an angle β with respect to the axis 124 . The significance of the angle β will be discussed in greater detail below in connection with FIG. 3 . Still referring to FIG. 2 , the tool 121 includes a receiver sub 125 and a transmitter sub 126 with a mud motor or other motor apparatus 127 disposed between the receiver and transmitter subs 125 , 126 . In the embodiment shown in FIG. 2 , the motor 127 includes a stator section 128 and a rotor section 129 . Accordingly, the rotor section 129 causes the transmitter 123 to rotate with respect to the receiver 122 . Of course, the transmitter and receiver functions are interchangeable and, while the tool 121 shown in FIG. 2 includes a rotating transmitter antenna 123 , the antenna 123 could serve as a receiver antenna and the antenna 122 could serve as a transmitter. Preferably, the motor 127 is a mud motor or other positive displacement motor (PDM). The drill bit is shown schematically at 105 close to tool 121 , but the tool 121 can be placed higher or farther above the drill bit 105 in the BHA 100 than what is illustrated schematically in FIG. 2 . Also, an antenna could be carried by drill bit 105 . Further, a transmitter antenna may broadcast at various frequencies.
Turning to FIG. 3 , the receiver antenna 122 is shown rotated by an angle φ relative to the x-axis of a non-rotating coordinate system that is referenced to a tool-fixed coordinate system in which the z axes of both systems are aligned. φ may be fixed or variable. The angle β is the angle between the dipole moment of the antenna and the z axis 124 . The transmitter antenna 123 is shown rotated at an angle φ plus α with respect to the non-rotating x-axis. In coordinates used herein, the z-axis corresponds to the tool axis 124 . Measurements at the receiver 122 include (1) the orientation angle or the tool face angle φ of receiver 122 with respect to the non-rotating x-axis; (2) the azimuthal angle difference a between the antennas 122 , 123 ; and (3) the signal or voltage V R received at the antenna 122 . The angles φ and α are independent of each other and a gives the relative rotation between the transmitter and receiver. The antenna configurations may be for a propagation or induction resistivity tool.
Still referring to FIG. 3 , when BHA 100 is undergoing rotation, the voltage V R can be expressed as a product of matrices as shown below in which the transmitter 123 and receiver 122 are tilted at an angle β with respect to the tool axis 124 . The receiver antenna 122 is rotated with respect to the non-rotating x axis by an angle φ, and the relative rotation angle is given by α. For the tool 121 shown in FIGS. 2 and 3 , the voltage V R can be expressed as shown in Equation 1a for any tilt angle β.
V
R
=
(
cos
α
·
sin
β
,
sin
α
·
sin
β
,
cos
β
)
·
[
cos
ϕ
sin
ϕ
0
-
sin
ϕ
cos
ϕ
0
0
0
1
]
·
[
XX
XY
XZ
YX
YY
YZ
ZX
ZY
ZZ
]
·
[
cos
ϕ
-
sin
ϕ
0
sin
ϕ
cos
ϕ
0
0
0
1
]
·
(
sin
β
0
cos
β
)
(
1
a
)
If β=45° Equation 1a reduces to that shown as Equation 1b.
V
R
=
1
2
(
cos
α
,
sin
α
,
1
)
·
[
cos
ϕ
sin
ϕ
0
-
sin
ϕ
cos
ϕ
0
0
0
1
]
·
[
XX
XY
XZ
YX
YY
YZ
ZX
ZY
ZZ
]
·
[
cos
ϕ
-
sin
ϕ
0
sin
ϕ
cos
ϕ
0
0
0
1
]
·
(
1
0
1
)
(
1
b
)
The following Equations 2a and 2b can be obtained for the received signal or voltage V R from Equations 1a and 1b)(β=45° respectively:
V
R
=
cos
2
β
·
ZZ
+
sin
2
β
·
[
XX
+
YY
2
·
cos
α
-
XY
-
YX
2
·
sin
α
]
+
cos
β
·
sin
β
·
[
ZX
·
cos
ϕ
+
ZY
·
sin
ϕ
+
XZ
·
cos
(
α
+
ϕ
)
+
YZ
·
sin
(
α
+
ϕ
)
]
+
sin
2
β
·
[
XX
-
YY
2
·
cos
(
α
+
2
ϕ
)
+
XY
+
YX
2
·
sin
(
α
+
2
ϕ
)
]
(
2
a
)
V
R
=
1
2
[
ZZ
+
(
XX
+
YY
)
2
·
cos
α
-
(
XY
-
YX
)
2
·
sin
α
+
ZX
·
cos
ϕ
+
ZY
·
sin
ϕ
+
XZ
·
cos
(
α
+
ϕ
)
+
YZ
·
sin
(
α
+
ϕ
)
+
(
XX
-
YY
)
2
·
cos
(
α
+
2
ϕ
)
+
(
XY
+
YX
)
2
·
sin
(
α
+
2
ϕ
)
]
(
2
b
)
Equation 2a for V R can be re-written as a sum of the nine terms 3a-3i shown below:
cos
2
β
·
ZZ
(
3
a
)
sin
2
β
·
XX
+
YY
2
·
cos
α
(
3
b
)
-
sin
2
β
·
XY
-
YX
2
·
sin
α
(
3
c
)
cos
β
·
sin
β
·
ZX
·
cos
ϕ
(
3
d
)
cos
β
·
sin
β
·
ZY
·
sin
ϕ
(
3
e
)
cos
β
·
sin
β
·
XZ
·
cos
(
α
+
ϕ
)
(
3
f
)
cos
β
·
sin
β
·
YZ
·
sin
(
α
+
ϕ
)
(
3
g
)
sin
2
β
·
XX
-
YY
2
·
cos
(
α
+
2
ϕ
)
(
3
h
)
sin
2
β
·
XY
+
YX
2
·
sin
(
α
+
2
ϕ
)
(
3
i
)
Equation 2b (β=45°) for V R can also be re-written as the sum of the nine terms 4a-4i shown below (each term needing to be scaled by ½):
ZZ
(
4
a
)
(
XX
+
YY
)
2
·
cos
α
(
4
b
)
-
(
XY
-
YX
)
2
·
sin
α
(
4
c
)
ZX
·
cos
ϕ
(
4
d
)
ZY
·
sin
ϕ
(
4
e
)
XZ
·
cos
(
α
+
ϕ
)
(
4
f
)
YZ
·
sin
(
α
+
ϕ
)
(
4
g
)
(
XX
-
YY
)
2
·
cos
(
α
+
2
ϕ
)
(
4
h
)
(
XY
+
YX
)
2
·
sin
(
α
+
2
ϕ
)
(
4
i
)
The variables in those terms are the trigonometric functions involving φ and α. Using measurements made by the tool 121 and a fitting algorithm, V R can be fitted to an expression involving those trigonometric terms, thus providing various fitting coefficients. The measurements are taken for various (at least nine) values for φ and α. The nine terms 3a-3i or 4a-4i then relate the components of the electromagnetic coupling tensor to the fitting coefficients, either directly or as some combination of the coupling components.
FIG. 5 shows an embodiment 200 of the present method as a flow chart. In step 210 , a tool is disposed in a wellbore. Step 212 is to transmit energy from a transmitter antenna, and step 214 is to measure a signal received by a receiver antenna while one antenna rotates relative to the other.
The disclosed method and apparatus also yield all nine components of the coupling tensor when the antennas 122 , 123 are tilted at different angles, as illustrated in FIG. 4A . However, if the antennas 122 , 123 are configured such that at least one antenna is axial or transverse ( FIGS. 4B-4F ), while useful information may be had, not all nine components can be determined. For example, if the antennas 122 , 123 are transverse, as illustrated in FIG. 4B , the coupling components that can be determined are limited to XX, XY, YX, and YY. This can been seen by substituting β=90° into Equation 1a. The embodiment of FIG. 4G , because of the radial offset of transmitter antenna 123 , does yield all nine components, though Equation 1a would have to be slightly modified to account for the offset. In U.S. Patent No. 6,509,738 by Minerbo et al, the use of offset parallel antennas is described.
The derivation above assumes rotation of the BHA 100 and a relative rotation between an upper portion of BHA 100 and a lower portion of BHA 100 . The rotation angle of the upper portion of BHA 100 is φ, and the relative rotation angle of the lower portion of BHA 100 is given by the angle α. However, certain drilling operations, such as directional drilling, have drilling modes in which the upper portion of BHA 100 substantially does not rotate (“sliding mode”). The lower portion of BHA 100 , however, rotates whenever drilling is in progress (e.g., when drilling fluid is pumped and drives the mud motor). Thus, there is generally a relative rotation; that is, a is not constant, though φ might be.
Applying those constraints (i.e., fixed φ) in terms 3a-3i or 4a-4i leads to the conclusion that certain coupling components cannot be separated without further measurements. Specifically, because terms 3a, 3d, and 3e (or 4a, 4d, and 4e) have no a dependence, they will be lumped together by the fitting algorithm as a sum that is equal to a constant. That sum contains three unknown coupling components, but is a single equation. Thus, three independent measurements must be obtained to resolve the three unknown components.
One way in which this can be accomplished is by making measurements with three distinct φ values. That is, the upper portion of BHA 100 must be rotated to three different orientations, and measurements as a function of a must be made at each of the “fixed” orientations, Alternatively, additional receiver antennas may be added to provide sufficient independent measurements. For example, three orthogonal receiver antennas may be used.
In addition, certain assumptions may reduce the number of couplings that need to be resolved. For example, a 1D formation model (“layer cake”) leaves only five coupling components since proper rotational manipulation of the coordinate systems zeros out the off-diagonal components having a Y coupling. A general 3D formation model, however, would require three receiver antennas to resolve all nine components while in sliding mode. While specific embodiments have been described in terms of certain transmitters and receivers, it is well known in the art, by the theory of reciprocity, that the roles of receivers and transmitters may be interchanged. Also, while the described embodiments have a rotating transmitter portion and a sometimes rotating, sometimes sliding receiver portion, the receiver antennas could be on the rotating portion and the transmitters on the sometimes rotating, sometimes sliding portion. For example, for the 3D formation model example above, if a receiver were on the rotating portion, three transmitters on the sometimes rotating, sometimes sliding portion would suffice.
In a wireline embodiment, one of the antennas 123 or 122 is rotated relative to the other while the measurements are made. The relative rotation may be effected either physically or the broadcast signal can be steered, for example, by phasing. If the actual antenna rotation is not feasible, then a virtual rotation can be mathematically created by linear combinations of the other measurements. U.S. Pat. Nos. 6,181,138 and 6,794,875 both describe how to generate the response of a virtual receiver with arbitrary angle relative to the tool axis. Note that for such applications more than one transmitter 123 /receiver 122 pair will be needed.
While only certain embodiments have been set forth, alternatives and modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the scope of this disclosure and the appended claims. | A logging tool and method to make subsurface measurements is disclosed, wherein the tool is placed within a borehole penetrating a formation. The tool has a transmitter antenna and a receiver antenna spaced apart along a longitudinal axis of the tool, and at least one of the transmitter or receiver antennas has a dipole moment that is non-coaxial with the longitudinal axis of the tool. The at least one non-coaxial antenna can rotate relative to the other antenna. Energy is transmitted from the transmitter antenna and a signal associated with the transmitted energy is measured at the receiver antenna while the at least one non-coaxial antenna rotates relative to the other antenna. | 4 |
FIELD OF THE INVENTION AND RELATED ART
The present invention relates to production of a liquid crystal panel usable for image display, etc., more particularly to a method and an apparatus for injecting a liquid crystal into a panel by the vacuum injection scheme utilizing the viscosity of the liquid crystal.
Hitherto, a smectic liquid crystal or a ferroelectric liquid crystal has been injected into a liquid crystal panel by the vacuum injection scheme as utilized for nematic liquid crystals. An injection apparatus used for the vacuum injection scheme may for example have a structure as illustrated in FIG. 2. The apparatus includes a vacuum chamber 104 in which a liquid crystal panel 101 is disposed with its injection port 103 directed downward, and a liquid crystal pan 105 containing a liquid crystal 106 is disposed at the bottom. Below the liquid crystal pan 105 is disposed a heater 109 to control the temperature of the liquid crystal. Generally above the liquid crystal panel 101 is disposed an applicator 111 for applying the liquid crystal onto the injection port 103. The applicator 111 is held invertible upside down by an applicator rotator 110 and movable up and down by an applicator elevator (not shown).
For the liquid crystal injection, the vacuum chamber 104 is set in vacuum and the interior of the liquid crystal panel 101 is reduced in pressure. Then, the applicator 111 is caused to contact the liquid crystal 106 on the liquid crystal pan 105 so as to attach the liquid crystal thereto. The viscosity of the liquid crystal at this time is ordinarily set to 0.001-0.004 kg/ms. Then, the applicator 111 is moved upward, and the viscosity of the liquid crystal attached to the applicator is adjusted to 0.01-0.02 kg/ms. Then, the liquid crystal is applied onto the injection port 103 of the panel 101 and heated by a heater provided therefor to lower the viscosity, thereby injecting the liquid crystal into the panel 101 by utilizing the capillary effect. Further, the pressure within the vacuum chamber 104 is restored to the atmospheric pressure to complete the liquid crystal injection by utilizing the resultant pressure difference.
There has been proposed a method of applying a smectic liquid crystal over the injection port of a liquid crystal cell while heating the liquid crystal into isotropic phase. (Japanese Laid-Open Patent Application (JP-A) 61-35429).
According to the conventional liquid crystal injection method, the smectic liquid crystal applied to the injection port is placed in isotropic phase or cholesteric phase, thus having an unstable fluidity. As a result, before shifting into the injection step, the liquid crystal is partly injected into the panel so that it has been difficult to control the application amount thereof to the injection port. In case where the application amount is insufficient, the atmospheric air is liable to-enter through the injection port to destroy the vacuum within the panel, thus causing liquid crystal injection failure. If the application amount is excessive, the liquid crystal is liable to enter up to the display region of the panel in the application step, thereby causing an alignment failure.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method and apparatus allowing a stable liquid crystal injection, so as to solve the above-mentioned problems.
According to the present invention, there is provided a method of injecting a smectic liquid crystal into a liquid crystal panel by vacuum injection scheme, comprising: applying the liquid crystal over an injection port of a blank panel, while maintaining the panel at a temperature below a temperature at which the liquid crystal shows a fluidity and controlling the liquid crystal at a viscosity within the range of 0.0005-0.005 kg/ms. In a preferred embodiment of the present invention, a ferroelectric liquid crystal is injected into a liquid crystal panel according to the vacuum injection scheme through sequential steps of heating the liquid crystal within a liquid crystal pan disposed within a vacuum chamber at a temperature providing isotropic phase of the liquid crystal, attaching the liquid crystal in the isotropic phase to an applicator held at room temperature, heating the liquid crystal on the applicator to or above .a temperature providing the isotropic phase of the liquid crystal to thereby level the liquid crystal thereon, and applying the liquid crystal after natural cooling over the injection port of the panel. It is further preferred that the liquid crystal is applied over the injection port of the panel at a viscosity of 0.0007-0.0009 kg/ms.
According to a second aspect of the present invention, there is provided an liquid crystal injection apparatus suitable for practicing the above liquid crystal injection method and an applicator equipped with temperature control means. It is preferred that the applicator has a liquid crystal-carrying surface forming an arcuate groove and coated with a fluorine-containing resin so as to facilitate the application of an optimum amount of the liquid crystal over the injection port.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a liquid crystal injection apparatus according to an embodiment of the present invention.
FIG. 2 illustrates a conventional liquid crystal injection apparatus.
FIG. 3 is a perspective view showing a liquid crystal-carrying surface of an applicator suitably used in the present invention.
FIG. 4 is a perspective view showing a liquid crystal-carrying surface of a conventional applicator.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment according to a fist aspect of the present invention will now be described.
EXAMPLE 1
A blank liquid crystal panel 101 as shown in FIG. 1 having a 40 mm-wide injection port 103, an about 4 mm-wide sealing part 102 and a panel gap of 1.4 μm, was prepared. A liquid crystal used for filling the panel was a pyrimidine-based ferroelectric liquid crystal showing viscosities of 0.125 kg/ms at 10° C., 0.044 kg/ms at 30° C., 0.014 kg/ms at 50° C., 0.002 kg/ms at 90° C. and 0.0003 kg/ms at 100° C. The liquid crystal was injected into the blank panel by using a vacuum injection apparatus as shown in FIG. 1.
Referring to FIG. 1, a blank panel 101 as described above and a liquid crystal pan 105 containing liquid crystal 106 as described above were placed within a vacuum chamber 104. Then, the interior of the vacuum chamber 104 was evacuated to vacuum by a vacuum pump 108 through open vent valve 107 and simultaneously the liquid crystal 106 within the pan 105 was heated by a heater below the pan 105 to 105° C., thereby causing the liquid crystal to show a viscosity of 0.002 kg/ms. Then, an Al-made applicator 111 having a liquid crystal-carrying surface 111a was driven by an applicator elevator (not shown) and an applicator rotator 110 so as to have the liquid crystal 106 attach the liquid crystal onto the surface 111a. Then, the applicator 111 was inverted by an angle of 180 degrees and elevated by the applicator elevator at a rate of 60 cm/min to apply the liquid crystal over the injection port 103 of the panel 101. Before the application, however, a heater 113 embedded within the applicator 111 was temperature-controlled by an external controller 114 to control the liquid crystal at a temperature of 90° C. and a viscosity of 0.002 kg/ms.
As a result, an appropriate amount of the liquid crystal could be applied over the injection port 103 of the panel 101, so that the liquid crystal was satisfactorily injected into the panel 101 by restoring the pressure within the vacuum chamber 104 to the atmospheric pressure, without causing an injection failure due to invasion of the atmospheric air or an alignment failure due to entering of the liquid crystal up to the display region already at the time of the liquid crystal application due to application of an excessive amount of the liquid crystal over the injection port.
Comparative Example 1
The liquid crystal injection was performed in a similar manner as in Example 1 except that the liquid crystal was applied over the injection port 103 of the liquid crystal panel 101 at a viscosity of 0.008 kg/ms (75° C.) outside the prescribed range of 0.0005-0.005 kg/ms. As a result, the vacuum within the panel was not retained until the completion of the filling by invasion of the atmospheric air into the panel, thus causing an injection failure.
On the other hand, the applicator 111 was elevated faster than in Example 1 to apply the liquid crystal at a viscosity of 0.0003 kg/ms (100° C.), whereby the liquid crystal entered up to the display region of the panel already at the time of the application and resulted in an alignment failure after complete filling of the liquid crystal by the restoration of the atmospheric pressure within the vacuum chamber 104.
EXAMPLE 2
An applicator having an Al-made liquid crystal-carrying surface provided with arcuate grooves as shown in FIG. 3 in contrast with conventional flat surfaces as shown in FIG. 4 and coated with polytetrafluoroethylene was used as an applicator 111 in the vacuum injection apparatus shown in FIG. 1. A pyrimidine-based mixture ferroelectric liquid crystal showing the following phase transition series was injected into a blank panel 101. ##STR1##
A blank panel 101 was first disposed within a vacuum chamber 104. Then, a shutter 112 was closed, a panel-side chamber was reduced in pressure to 10 -3 Torr and then the evacuation was further continued for 12 hours. On the other hand, the above-mentioned liquid crystal 106 was placed on a liquid crystal pan 105 and heated into isotropic phase at 95° C. by a heater 109. Then, a lower half of the liquid crystal chamber 104 was reduced to 10 -3 Torr, and a liquid crystal-carrying surface 111a of the applicator held at room temperature was dipped within the liquid crystal 106 on the liquid crystal pan 105 and pulled up gradually. Then, a heater 113 controlled by an external controller 114 was actuated to heat the applicator 111 at 95° C. and the liquid crystal applied onto the applicator surface 111a (which had been directed upward by a rotator 110) was leveled for 10 min. so as to allow uniform application.
After the leveling, the liquid crystal was naturally cooled to a viscosity of 0.0007-0.0009 kg/ms. Then, the shutter 112 was opened, and the liquid crystal applied on the applicator was allowed to contact and was applied over the injection port 103 of the panel 101 held at room temperature.
Then, the liquid crystal applied over the injection port 103 was injected into the panel by restoring the atmospheric pressure within the vacuum chamber. As a result, a ferroelectric liquid crystal panel free from inclusion of bubbles and showing excellent display quality was obtained.
Comparative Example 2
The liquid crystal injection was performed in a similar manner as in Example 2 except that the liquid crystal was applied without effecting the temperature control of the applicator 111. As a result, the viscosity at the time of application was fluctuated within a broad range of 0.0001-0.02 kg/ms, thus frequently falling outside the prescribed optimum range of 0.0005-0.0005 kg/ms. Thus, in case of too low a viscosity, the liquid crystal entered up to a display region of a liquid crystal panel to result in an alignment failure.
On the other hand, in case of too high a viscosity, the liquid crystal could not be applied uniformly over the injection port, thus resulting in defects of bubble inclusion within the panel.
In any case, the display quality was remarkably impaired.
As described above, according to the present invention, a liquid crystal can be injected into a liquid crystal panel well and uniformly without causing inclusion of bubbles within the injected liquid crystal or causing an alignment failure, whereby liquid crystal panels of a high quality can be produced at a high reliability. Thus, the liquid crystal panels can be produced at a higher yield and at a higher production efficiency, thus resulting in a lower production cost. | A smectic liquid crystal is injected into a liquid crystal panel according to the vacuum injection scheme. The liquid crystal is applied over an injection port of a blank panel while maintaining the panel at a temperature below a temperature at which the liquid crystal shows a fluidity and controlling the liquid crystal at a viscosity of 0.0005-0.005 kg/ms. As a result, an appropriate amount of the liquid crystal can be applied, thereby providing a liquid crystal panel free from inversion of bubbles and good and uniform alignment free from alignment failure. | 6 |
TECHNICAL FIELD
[0001] The invention is based on a tender lift for watercraft, which serves as a lifting platform for persons, but especially as a lift for tenders and similar enabling them to be taken up, to be parked and to be locked, according to a high safety standard, which also includes the lifting mechanism and the connecting stair, according to the generic name of the first claim.
BACKGROUND OF THE INVENTION
[0002] Height adjustable carrier platforms are being used more and more to collect tender boats, as described in U.S. Pat. No. 4,157,596, GB 2319014, DE 199 63 057 C1, or WO 03/106254 A1, but also for the convenient boarding and deboarding of bathing guests and divers. Besides this, height adjustable carrier platforms are also being used for commercial purposes, as for e.g. in rescue operations.
SUMMARY OF THE INVENTION
[0003] The invention involves that, at the transom of a watercraft, a height adjustable platform is fixed, which, at the same time, can be a swim platform and a tender platform with the aim being the controlled pick up of tenders and similar and which places these in a space-saving manner on the platform or in an adjacent garage and fixes these in a manner fit for travelling on the sea. Furthermore the mechanism is designed in such a way that the swivel arms safely avoid cutting and bruising. So as not to use the lift continually when this is in the down position, for e.g. to bring something quickly on board or to cast off, there is a simple, integrated and in case of overload releasable connecting stair available so that one can move quickly and easily from the watercraft to the platform and vice versa.
[0004] The pickup of a tender boat or jetski, here called in the abbreviated form tender, is not easy to accomplish in choppy sea as the yacht has a different rolling and pitching movement compared to the small tender. For this reason means have been provided so that the tender driver can take course to the lifting platform in a simple way and can drive onto it in a concentrated manner and will be automatically stopped at the right place, so that the driver then only has to give the order for the platform to be lifted, and while doing so, respectively time delayed, the tender brings itself into position so as to be parked in a space saving manner on the yacht deck or on the platform in the home position. The safe lifting of the tender is guaranteed by already placing it in an appropriate clasp so that the tender cannot slip off the lifting platform in heavy seas. The positioning, the securing and finally the locking of the lifting platform with the tender is executed without the help of third parties; as in this regard this is a further precautionary measure as people on the lifting platform trying to turn and rig the tender are risk factors especially on leisure craft yachts as often no professional crew is on board.
[0005] As far as the invention is concerned this is dealt with by the features of the first claim
[0006] Core of the invention is a lift, fixed to the transom of a watercraft, which serves as a bathing and tender platform and which guarantees a high safety standard with regard to reliable and space-saving picking up of a tender without the assistance of third parties, as well as having a built in safety mechanism to avoid cutting and bruising, as well as having a smart, self-unfolding ladder integrated between the watercraft's transom and the lift
[0007] Further advantageous features of the invention are listed in the subclaims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Various exemplary aspects of the invention will be described with reference to the drawings, wherein
[0009] It shows
[0010] FIG. 1 a schematic side view of a platform lift with the constructive cover of the swivel arm parallelogram
[0011] FIG. 2 a schematic front view of the swivel arms in cross-sections
[0012] FIGS. 3 a, b, c a schematic sideview of motion sequences when picking up a tender and placing it on the platform
[0013] FIG. 4 a 3D view of the revolving plate with the holding and locking elements
[0014] FIG. 5 a schematic sideview of the platform with the revolving plate and a mechanical coercion steering
[0015] FIG. 6 a schematic overhead view of the platform with the revolving plate and with a cylinder and a controller
[0016] FIG. 7 a schematic sideview of the elevated platform with a rail mean positioned on the revolving plate and with a tender
[0017] FIG. 8 a schematic sideview of an extendable and releasable connecting ladder between the transom of the watercraft and the platform.
[0018] Only essential elements of the invention are schematically shown to facilitate immediate understanding.
DETAILED DESCRIPTION OF EMBODIMENTS
[0019] FIG. 1 shows a schematic sideview of a tenderlift 1 , which is fixed to the transom 2 of a watercraft, with both swivel arms 3 a , 3 b , which form a parallelogram. It is known that with a parallelogram the corresponding gap sizes of both swivel arms 3 a , 3 b do change according to stroke position H 1 , H 2 and thereby can cause bruising to third parties. Because of the constructive overlapping by a suitable profile and an accurate positioning of the swivel arms 3 a, b to each other, the gap 3 c can be therewith covered so at the same time increasing the stability of the swivel arms 3 a , 3 b . Conceivable is a covering of the swivel arms 3 a , 3 b with plastic elements, but the one part solution, namely to protect the swivel arms 3 a , 3 b from the open gap 3 c , and at the same time to increase the stability of the arms, is evidently an ideal combination. The forms of the support 4 are also designed in such a way, for e.g. roundings 4 a with large radiuses, but also by constructive inclusion and integration of the support 4 into the swivel arms 3 a , 3 b , so that also in these places foreign objects, whether it be limbs, deadwood or anchor ropes and similar getting stuck is practically eliminated. In addition the lift cylinder 5 is integrated as much as possible into the swivel arms 3 a, b and where this is not feasible, it is wrapped separately with a casing 5 a , so that the stroke movement and swiveling of the lift cylinder 5 cannot lead to injuries to third parties or malfunction of the equipment.
[0020] FIG. 2 Shows a schematic front view of the swivel arm cross-section of the swivel arms 3 a , 3 b , whereby as an example only the swivel arm 3 a has a U profile whereas the swivel arm 3 b has a closed profile, whereby with the characteristic that both of the swivel arms 3 a , 3 b drift apart no more than the measurement a at the lift stroke H, which means that the construction of the tenderlift 1 is so designed that, in the worse scenario, both of the swivel arms 3 a to swivel arms 3 b are in line to each other, in normal cases are nested in each other. As an example through the design of the sheet metal a more rigid design is recognizable which can more easily pick up technical mean 6 such as torsion tube or bearings or lift cylinder 5 .
[0021] FIG. 3 Shows a schematic stem view of movement sequences when taking up a tender 7 onto the platform 8 . The problematic of collecting a tender 7 on board within a reasonable time even in slight choppy sea is not easy and generally needs a second or even a third person to place the tender 7 properly. Afterwards this has to be raised and tied down fast.
[0022] FIG. 3 a Shows now how the tender 7 can be driven in between the guiding sticks 9 a, b , which not only easily and comfortably help to drive on the tender 7 but both of the front guiding sticks 9 a , corresponding to the tender's hull shape also are nearer together, so that the tender 7 can only be driven in to a predetermined place and is halted there by the narrowing of the front guiding sticks 9 a . In addition, the guiding sticks 9 a, b have an upper bracket in form of for e.g. a curved element 9 c so that this can prevent the tilting out of the tender 7 . Hence the tender 7 is quickly and safely brought into position. Under the hull of the tender 7 are deadrise elements 10 , which make sure that the tender 7 lies in a stable position. Through the tender locking 11 , which is activated manually by means of a catch lock or by motor, it is guaranteed that the tender 7 cannot involuntarily glide out backwards out of the enclosure of the guiding sticks 9 a, b.
[0023] The guiding sticks 9 a, b and the deadrise elements 10 are fixed on a revolving plate 12 , which with the tender 7 fixed onto it, can be pivoted by 90 degrees by the corresponding mean, so that the tender 7 is finally held on the transom 2 crosswise to the driving direction of the yacht.
[0024] The rotation of the tender on the revolving plate is carried out either synchronously with the lifting of the tenderlift 1 , or coercion controlled or by means of a cylinder and a controller or independently from lift stroke H of the tenderlift 1 controlled by means of corresponding electronics.
[0025] FIG. 3 b Shows the lifted, already partly pivoted tender 7 over the waterline WL. The rotation is necessary as the platform 8 does not have the appropriate depth which corresponds to the length of a tender 7 . Yachts, however, have enough width to also take up fairly large tenders 7 and are therefore usually fixed crosswise to the yacht.
[0026] FIG. 3 c Shows the tenderlift 1 completely driven up and the crosswise placed tender 7 , which is fixed on the platform 8 in a seaworthy position by means of deadrise elements 10 , guide sticks 9 a, b , curved element 9 c , tender locking 11 , without the help of third parties. In principle the tender 7 can also be driven on the platform 8 sideways should the watercraft not have any design enclosure on the platform 8 , this is only in heavy seas less easier to accomplish, but with the guiding sticks 9 a, b , curved element 9 c , deadrise elements 10 and tender locking 11 this form of tender pick is also possible.
[0027] FIG. 4 Shows a 3D view of the revolving plate 12 which is embedded in the platform 8 , with the guiding sticks 9 a, b , the curved element 9 c , the deadrise elements 10 and the tender locking 11 . The deadrise elements 10 and the guide sticks 9 a, b fixed onto it and the tender locking 11 have hinges 13 , which enable these parts to sink into the opening hatch means 14 of the revolving platform 12 , so that the platform 8 forms an area with the revolving plate 12 and no interfering parts rear up when a tender 7 is not on the platform. The platform can be pivoted in both directions according to arrow T.
[0028] FIG. 5 Shows a schematic sideview of the platform 8 with the revolving plate 12 , which by means of a pivot bearing 15 and a bracket 16 can be pivoted easily on the platform 8 as well as being fixed with no backlash. On one of the swivel arms 3 a, b a rod 17 is rotationally mounted, which is connected to a cam 18 , which again is fixed and hinged to the revolving plate 12 . Thereby a simple but efficient coercion control is produced, as via the lift stroke H of the swivel arms 3 a, b , respectively of the platform 8 , the rod 17 is pressed into arrow position Z and executes thereby a forced pivoting of the revolving plate 12 . By means of a suitable distance of the cam 18 from the centre of the platform 8 , the rotation T can be configurated in such a way that at a corresponding diving depth the tender 7 is watered and thereby the rotation T is exactly at 90 degrees or at any other required setting.
[0029] FIG. 6 Shows a schematic sideview of the platform 8 with the revolving plate 12 , which by means of a pivot bearing 15 and a bracket 16 is fixed smoothly, pivotable and as well as with no backlash. On one of the pivoting arms 3 a, b an operating cylinder 19 is fixed instead of the rod 17 , which based on the command of the corresponding programmed controller 20 , activates the revolving plate 12 which turns according to arrow T. Thereby the tender 7 can for e.g. firstly be turned by 90 degrees before the tenderlift 1 gets lifted, or any other configuration, which is advantageous for the tender 7 and the lifting procedure.
[0030] FIG. 7 shows a schematic sideview of an elevated platform 8 with a rail mean 21 positioned on the revolving plate 12 , which has respective gliding elements 22 , for e.g. in the form of wheels or carriage which sit on a rail set 23 . On the rail mean 21 are the guiding sticks 9 a, b with the curved element 9 c , the deadrise elements 10 and the tender locking 11 . The rail mean 21 on the platform 8 can be driven in the elevated position of the tenderlift 1 according to arrow R in the direction of the transom support 2 a and the tender 7 can be driven away from tenderlift 1 , so that this can be used purely as a bathing platform lift, or the tender 7 can be pushed into a garage inside the watercraft. After shifting the rail mean is locked safely in the desired position by means of the rail locking 24 . The shifting of the rail mean 21 can be done manually or by motor.
[0031] FIG. 8 shows a schematic sideview of a retractable and releasable connecting ladder 25 which is hinged on the one hand to the transom 2 of the watercraft and on the other hand to the platform 8 , hinged and mounted flexibly lengthways in a guide tube 26 . The connecting ladder 25 when lifting up the tenderlift 1 thus comes to lie under the platform 8 like a telescopic ladder. Instead of a ladder a stairway can also be used. In addition the pivot bearing 27 of the connecting ladder 25 has release elements 28 , so that should there be a buckling or jamming of foreign bodies on or in the connecting ladder 25 , this is released and thus safeguarding any damage to the jammed object as well as the tenderlift 1 . The release can be a clip or a power operated mean by hydraulics or pneumatic load operated mean.
[0032] Of course the invention is not only applicable on shown and described examples.
DRAWING LIST
[0000]
1 tenderlift
2 transom
2 a transom support
3 a , 3 b swivel arms
3 c gap
4 support
4 a rounding
5 lift cylinde
5 a casing
6 technical mean
7 tender
8 platform
9 a , 9 b guiding stick
9 c curved element
10 deadrise element
11 tender locking
12 revolving plate
13 hinge
14 hatch mean
15 pivot bearing
16 bracket
17 rod
18 cam
19 operating cylinder
20 controller
21 rail mean
22 gliding element
23 rail set
24 rail locking
25 connecting ladder
26 guide tube
27 pivot bearing
28 release element
H lift stroke
T rotations
a gap stroke
R rod stroke
Z rod | The invention comprises of a tenderlift ( 1 ) for watercraft with a high safety standard, such as the safe picking up of the tender ( 7 ) by means of guide sticks ( 9 a, b ), curved elements ( 9 c ), deadrise elements ( 10 ), tender locking ( 11 ) as well as for an easier positioning of the tender on the platform ( 8 ) with an integrated revolving plate ( 12 ) which) can be accordingly turned by coercion adjustment or by means of an operating cylinder ( 19 ). In addition the swivel arms ( 3 a , b) are concealed, so that no gap ( 3 c ) can occur and no bruising of limbs or other means can occur. When the tenderlift ( 1 ) goes down, the integrated ladder ( 25 ), lying under the platform ( 8 ), automatically extends with the stroke (H), which has release elements ( 28 ) on the pivot bearing ( 27 ) | 1 |
SUMMARY OF THE INVENTION
This invention is concerned with a novel process for preparing a diarylmethanol 3 especially a 1,1-diarylprolinol, which comprises treating the corresponding N-carboxy anhydride 2 with an aryl metal, especially a phenyl metal, such as an aryl lithium, aryl zinc, aryl cesium or aryl magnesium halide, especially the chloride: ##STR5##
The invention is also concerned with a process for preparing a chiral catalyst 1 by treating the 1,1-diarylmethanol with a trisubstituted boroxin 4; ##STR6##
The invention is also concerned with the novel catalyst 1, wherein R is an aromatic group, either unsubstituted or substituted.
The catalyst produced by the novel process of this invention is useful for directing the chirality of reductions of ketones with boranes such as diborane, borane-dimethyl sulfide, or borane-THF to chiral secondary alcohols such as in the synthesis of a chiral intermediate 5 in the synthesis of the known carbonic anhydrase inhibitor 6 useful in the treatment of ocular hypertension and glaucoma. ##STR7##
BACKGROUND OF THE INVENTION
(S)-1,1-Diphenylprolinol the principal compound of structure 3 is a known compound and has been prepared by a variety of processes, all involving a fully protected pyrrolidine. See for example Enders et al., Org. Synth., Col. Vol. 5, 542-549; Corey et al., J. Amer. Chem. Soc., 1987, 109, 7926-7927; French Patent FR 3638M, 1965; Kapfhammer, et al. Hoppe-Seylers Zeit. Physiol. Chem. 1933, 223, 43-52; German Patent DE 3609152A1, 1987; Corey et al., J. Amer. Chem. Soc., 1987, 109 5551-5553; J. Org. Chem. 1988, 53, 2861-2863; Enders et al., Bull Soc. Chem. Belg., 1988, 97, 691-704. These prior art processes involve multiple steps and rather low overall yields.
For example preparation of (S)-1,1-diphenylprolinol via the procedure described in the literature [Corey et. al., J. Am. Chem. Soc. 1987, 109, 5551-5553] afforded a 30-40% overall yield of the amino-alcohol from (S)-proline. The process required multiple isolations [N-(benzyloxycarbonyl)-(S)-proline (solid, commerically available), N-(benzyloxycarbonyl)-(S)-proline methyl ester (viscous oil), and (S)-1,1-diphenylprolinol hydrochloride (solid, precipitated from diethyl ether), and (S)-1,1-diphenylprolinol (solid recrystallized from water/methanol)]. The Grignard addition to N-benzyloxycarbonyl)-(S)-proline methyl ester required a large excess (8 equiv) of phenylmagnesium chloride. The inital addition to form the intermediate 1,1-diphenylprolinol oxazolidinone occurs quickly at 0° C. The addition of phenylmagnesium chloride to the oxazolidinone affording the desired product, however, is much slower--requiring 12-18 hours at room temperature. Isolation of the amino-alcohol from the large excess of magnesium salts also was a problem--requiring multiple extractions from a magnesium hydroxide gel. The resultant product had an enantiomeric purity of 99:1 (S:R) by capillary GC (DB-23) of the Mosher amide derivative. ##STR8##
The methods reported for preparation of structure 1 (n═1, Ar═Ph, R═Me, R 1 , R 2 ═H), include reaction of the corresponding prolinol with methylboronic acid (1.1 equiv:1) in toluene at 23° C. in the presence of 4 Å molecular sieves for 1.5 hours; or 2) in toluene at reflux for 3 hours using a Dean-Stark trap for water removal; both followed by evaporation of solvent, and molecular distillation (0.1 mm, 170° C.) (Corey et al., J. Amer. Chem Soc., 1987 109, 7925-7926). An Alternate method reported for preparation of structure 1 (n═1, Ar═2-naphthyl, R═Me, R 1 R 2 ═H) involved heating a toluene solution of the corresponding prolinol and methylboronic acid (1.2 equiv) at reflux for 10 hours using a Soxhlet extractor containing 4 Å molecular sieves (Corey et al., Tetrahedron Lett., 1989, 30, 6275-6278). The key to these procedures is irreversible removal of two molecules of water, thus driving the reaction to completion. Chiral reductions using oxazaborolidine prepared via these methods provided erratic results with respect to yields and enantiomeric purity of the reduction products.
Now, with the present invention there is provided a novel improved procedure for preparation of the diarylmethanol 3; a novel improved method for the preparation of the oxazaborolidine catalyst, 1; and novel improved catalysts.
DETAILED DESCRIPTION OF THE INVENTION
The novel process for preparation of the diarylmethanol 3 comprises reacting an N-carboxyanhydride 2 with an aryl Grignard reagent: ##STR9## wherein n is 1 or 2; R 1 and R 2 independently represent hydrogen, C 1-3 alkyl or joined together represent with the carbons to which they are attached a benzo group or a double bond; Ar is (1) 2-naphthyl, (2) phenyl, or (3) phenyl substituted in the meta- and or para- positions with one or more of (i) halo, such as fluoro or chloro, (ii) C 1-4 alkyl, (iii) CF 3 or (iv) C 1-4 alkoxy.
The N-carboxyanhydride, 2, is synthesized from the corresponding amino acid such as (S)-proline in >95% yield by reaction with phosgene, diphosgene or triphosgene in THF followed by addition of triethylamine and filtration to remove the resultant triethylamine hydrochloride as described by Fuller et al., Biopolymers, 1976, 15, 1869-1871.
The novel process for converting the N-carboxyanhydride, 2, to the diarylmethanol, 3, comprises reacting an ArMgHal preferably ArMgCl, Grignard reagent with the N-carboxyanhydride in an ethereal solvent such as THF, diethyl ether or 1,2-dimethoxyethane, preferably THF at about -26° to 10° C. over a period of about 2 to 5 hours. It is preferred to add the N-carboxyanhydride to the Grignard reagent slowly (about 1 L/hour) to provide maximum yield and minimum racemization.
The diarylmethanol is isolated by slowly quenching the reaction with aqueous acid, preferably dilute sulfuric acid at about 0°-20° C., filtration to remove sulfate salts, concentration to a small volume and filtration to collect the sulfate salt of the diaryl methanol product 3 which can be further purified by washing with water and ethyl acetate and dried.
The novel process of this invention for preparation of the B-methyl oxazaborolidine catalyst (precursor) comprises reacting the diarylmethanol with a trimethylboroxine; ##STR10##
The process for the preparation of B-methyloxazaborolidines comprises the reaction of trimethylboroxine (0.67 to 1.0 equiv) with the diarylmethanol in an organic solvent such as toluene, benzene, xylene, chlorobenzene or the like at about 0° C. to 30° C. for about 0.5 to 4 hours until formation of the intermediate 5 is complete. The solution is then heated at about 80° C. to 150° C. for about 1 to 4 hours. The solvent is partially evaporated followed by multiple additions/concentrations of toluene or benzene to ensure complete removal of water and the methylboronic acid byproduct.
The novel intermediate of this invention has the structural formula 5; wherein n, Ar, R 1 and R 2 are as previously defined. It is preferred that n be 1, R 1 and R 2 be hydrogen, and that Ar be phenyl. ##STR11##
The novel process of this invention for preparation of the B-C 2-4 alkyl oxazaborolidine or B-aryl oxazaboro lidine catalyst (precursor) comprises reacting the diaryl methanol with a boroxine; ##STR12## wherein R is (1) C 2-4 alkyl, preferably butyl, (2) phenyl, (3) phenyl substituted with one or more of (i) halo, such as fluoro or chloro, (ii) C 1-4 alkyl, (iii) CF 3 , or (iv) C 1-4 alkoxy.
The process comprises the reaction of a boroxine (0.33 equiv) with the diarylmethanol in an organic solvent such as toluene, benzene, xylene, chlorobenzene or the like at about 0° C. to 30° C. for about 0.5 to 4 hours, then at 80° C. to 150° C. for about 12 to 24 hours with concurrent removal of water, using a Dean-Stark trap, molecular sieves, or azeo tropic distillation.
The novel catalyst of this invention has structural formula 1; ##STR13## wherein n, Ar, R 1 and R 2 are as previously defined and R is (1) phenyl, (2) phenyl substituted with one or more of (i) halo, such as fluoro or chloro, (ii) C 1-4 alkyl, (iii) CF 3 , or (iv) C 1-4 alkoxy.
It is prefered that n be 1, R 1 and R 2 be hydrogen, and that Ar be phenyl. It is also prefered that R be phenyl substituted with 4-fluoro or 4-C 1-4 alkyl group, especially methyl.
EXAMPLES
General
Melting points were determined on a Haake-Buchler melting point apparatus and are uncorrected. IR spectra were recorded on a Perkin-Elmer 1420 (as solutions in CCl 4 ) or a Nicolet 60SX FTIR spectrometer on microcrystalline solids using a Spectrascope accessory run at 4 cm -1 resolution. NMR spectra were recorded in deuterochloroform or deuteroacetonitrile on a Bruker AM-250 ( 1 H, 13 C), WM-250 ( 1 H, 11 B, 13 C), or AM-400 ( 1 H, 11 B, 13 C) spectrometer. 1 H chemical shifts are reported in ppm from an internal stand ard of residual chloroform (7.27 ppm) or acetonitrile (1.93 ppm). 11 B chemical shifts are reported in ppm from an external reference of boron trifluoride etherate (0.0 ppm). 13 C chemical shifts are reported in ppm from the central peak of deuterochloroform (77.0 ppm) or deuteroacetonitrile (1.3 ppm). Specific rotations were determined on a Perkin-Elmer 241 polarimeter. Concentrations (c) for specific rotations are reported in units of g/100 mL. Analytical gas chromatography (GC) was carried out on a Hewlett-Packard 5890A gas chromatograph equipped with a 7673A auto-sampler, split-mode injector, and flame-ionization detector, with helium as the carrier gas. The following capillary columns were employed: 30 m×0.32 mm DB-1 (J&W Associates) and 30 m×0.32 mm DB-23 (J&W Associates). Analytical high-performance liquid chromatography (HPLC) was carried out on a Hewlett-Packard Modular 1050 HPLC (quaternary pump and programmable variable-wavelength detector) using Column A: 250×0.46 mm DuPont Zorbax RX or Column B: 250×0.46 mm E. Merck Chirasphere. Analytical thin layer chromatography (TLC) was carried out on EM 0.25 mm silica gel 60F HPTLC plates using the following solvent systems: solvent A (45:45:9:1 hexane/dichloromethane/isopropanol/28% aq NH 4 OH: solvent B (7:3 hexane/EtOAc). Visualization was accomplished with UV light and/or by spraying with aqueous cerric ammonium molybdate followed by heating. Mass spectra were obtained on a Finnigan-MAT TSQ 70B Mass Spectrometer using either GC/MS with chemical ionization (NH 3 ) or FAB/MS using a DTT/DTE matrix. Combustion analyses were obtained in-house from our Analytical Research Department.
Reactions were carried out under an atmosphere of dry N 2 . As necessary Et 3 N, THF and toluene were dried over 3 Å or 4 Å molecular sieves. Residual water content was determined by Karl Fisher (KF) titration. (S)-Proline was obtained from Ajinomoto, (R)-proline from Tanabe U.S.A., Inc. Phosgene (1.93M in toluene) was obtained from Fluka. Phenylmagnesium chloride (2M in THF) was obtained from Boulder Scientific. Other Grignard reagents were either obtained from Aldrich, or prepared from the corresponding aryl bromide. Trimethylboroxine and n-butylboronic acid were obtained from Aldrich. Triarylboroxines were prepared from the corresponding arylboronic acids by heating a tol uene solution at reflux for 3-4 hours using a Dean-Stark trap for water removal, followed by evaporation of the solvent. (R)-MTPA (Aldrich) was converted to the acid chloride using oxalyl chloride (1.2 equiv) and catalytic DMF (0.05 equiv) in dichloromethane at 20°-25° C. for 4 hours followed by Kugelrohr distillation (45° C., 0.1 mBar).
EXAMPLE 1
Step A: Preparation of (S)-Tetrahydro[1H, 3H]pyrrolo-[1,2-c]oxazole-1,3-dione
A 5-L, three necked flask fitted, with a mechanical stirrer, nitrogen inlet tube, 1-L addition funnel, and teflon coated thermocouple probe, containing dry THF (1.15 L), was charged with (S)-proline (115 g, 1.00 mol). To the well stirred, cooled (15°-20° C.) suspension was added a solution of phosgene in toluene (1.93M, 622 mL, 1.20 mol) over a 0.5-1.0 hour period, maintaining the internal temperature at 15°-20° C. Caution: phosgene is an insidious poison. All manipulations with phosgene should be performed in a hood with good ventilation. Any excess phosgene should be decomposed in cold aqueous base. After the phosgene addition was complete, the mixture was warmed to 30°-40° C. and aged for 0.5 hour. During this time the mixture became homogeneous as proline reacted with phosgene to afford the intermediate N-carbamoyl chloride. Once homogeneous, the reaction mixture was aged an additional 0.5 hour at 30°-35° C., then cooled to 15°-20° C. While maintaining the internal temperature at 15°-20° C., the reaction mixture was concentrated in vacuo (1000 down to 50 mBar) to a volume of about 150 mL. Caution: hydrogen chloride (1 mol) and excess phosgene (200 mmol) are removed during the distillation. The use of appropriate traps, and venting of the vacuum pump to the hood is required. The reaction can be assayed at this point by 1 H NMR: (about 30 μL dissolved in 0.6 mL CDCl 3 ) δ11.5-10.0 (br s, 1H, CO 2 H), 7.3-7.1 (m, toluene), 4.62 (dd, 0.4H, C2--H rotamer), 4.50 (dd, 0.6H, C2--H rotamer), 3.9-3.5 (m, 2H, C5--H 2 ), 2.5-1.8 (m, 4H, C3--H 2 , C4--H 2 ). [The spectrum should not contain resonances at δ4.9 (dd, 0.4H, C2--H rotamer) and 4.7 (dd, 0.6H, C2--H rotamer) corresponding to proline N-carbamoyl chloride, acid chloride.] The residue was dissolved in dry THF (1.15 L), and the solution cooled to 0°-5° C. With good agitation, dry Et 3 N (106 g, 1.05 mol) was added over 15 minute while maintaining the internal temperature at 0°-5° C. After the addition was complete, the mixture was aged for 0.5 hour at 0°-5° C., then filtered through an enclosed, medium frit, sintered glass funnel. The resultant cake of Et 3 N HCl was washed with THF (3×200 mL). The filtrate and THF washes were combined to afford a solution containing product (about 0.95-1.0 mol) in THF (about 1.75 L) that was used immediately "as is" without further purification.
For analysis, a portion of the THF solution was concentrated in vacuo (20° C., 50 mBar) and the resultant white solid dried in vacuo (20° C., 0.01 mBar) overnight: mp 51°-52° C.; IR (CCl 4 ): 2980, 1845, 1780, 1350, 950, 920 cm -1 ; 1 H NMR (CDCl 3 ) δ4.34 (dd, J=7.4, 8.7 Hz, 1H, C2--H), 3.72-3.68 (m, 1H, C5--H 2 ), 3.32-3.18 (m, 1H, C5--H 2 ), 2.4-1.8 (m, 4H, C3--H 2 , C4--H 2 ); 13 C NMR (CDCl 3 ) δ168.9 (C3), 154.9 (C1), 63.1 (C3a), 46.5 (C6), 27.6 (C4), 26.9 (C5).
Anal. Calcd for C 6 H 7 NO 3 : C, 51.06; H, 4.96; N, 9.93. Found: C, 51.23; H, 4.84; N, 9.65.
Step B: Preparation of (S)-α,α-Diphenyl-2-pyrrolidinemethanol
A 5-L three necked flask fitted with a mechanical stirrer, nitrogen inlet tube, 2-L addition funnel containing the THF solution of product from Step A, and teflon coated thermocouple probe, was charged with a solution of phenyl magnesium chloride in THF (2.0M, 1.5 L, 3.0 mol). The Grignard reagent was cooled to -15° C. The THF solution of product from Step A (about 0.95-1.0 mol) was added over a 1 hour period while maintaining the internal temperature at -10° to -15° C. After the addition was complete, the mixture was aged for 3 hours at -15° C. and 1 hour at 0° C. The reaction was quenched into a 12-L mechanically stirred flask, containing a pre-cooled (0° C.) solution of 2M aqueous H 2 SO 4 (2.0 L, 4.0 mol), over a 0.5-1.0 hour period while maintaining the internal temperature below 20° C. During the quench, a thick white precipitate of MgSO 4 formed. The mixture was agitated for 1 hour at 0° C., and filtered through a 3-L, medium frit, sintered glass funnel. The MgSO 4 cake was washed free of residual product with THF (3×1.0 L). The filtrate and THF washes were combined and concentrated at atmospheric pressure to a volume of 2.0 L. Caution: benzene (about 82 g), formed during the quench of excess PhMgCl, is removed during the concentration. The product as its sulfate salt, Ph 2 CO, and Ph 3 COH precipitate during the concentration. The mixture was cooled to 0°-5° C., aged 1 hour, and filtered. The cake was washed with H 2 O (2×200 mL) to remove excess H 2 SO 4 , and EtOAc (3×350 mL) to remove the Ph 2 CO and Ph 3 COH. The cake was dried in vacuo (40° C., 50 mBar) affording 221 g (73% from proline) of the sulfate salt of the product as a white solid: mp 275°-290° C. (dec).
Anal. Calcd for C 34 H 40 N 2 O 6 S: C, 67.52; H, 6.67; N, 4.63. Found: C, 67.75; H, 6.67; N, 4.51.
A portion of the sulfate salt was converted to the free base as follows: to a mechanically stirred solution of THF (50 mL) and 2M aqueous NaOH (50 mL, 100 mmol) at 20° C. was added the sulfate salt (15.1 g, 50.0 mmol). The mixture was stirred at 20° C. until all solids dissolved, and was then diluted with toluene (200 mL). The two-phase mixture was filtered through a medium frit sintered-glass funnel, partitioned, and the organic layer washed with H 2 O (25 mL). The organic layer was concentrated in vacuo (50° C., 1 mBar) affording 12.5 g (99% yield) of product as a colorless oil that crystallized on standing. An analytical sample was prepared by recrystallization from hexane: mp 79°-79.5° C. [Lit. mp 76.5°-77.5° C. (H 2 O/MeOH); mp 80°-82° C. (EtOH)]; IR (CCl 4 ) 3600-3300 (br), 3170, 3140, 2980, 2790, 1490, 1450, 1400, 1170 cm -1 ; 1 H NMR (CDCl 3 ) δ7.7-7.5 (m, 4H, Ar--H), 7.4-7.1 (m, 6H, Ar--H), 4.65 (s, 1H, O--H), 4.3 (t, J=7.4 Hz, 1H, C2--H), 3.1-2.9 (m, 2H, C5--H 2 ), 1.9-1.5 (m, 5H, C3--H 2 , C4--H 2 , N--H); 13 C NMR (CDCl 3 ) δ148.21, 145.41 (C1', C1"), 128.24, 127.98 (C3', C3", C5', C5"), 126.46, 126.36 (C4', C4"), 125.88, 125.55 (C2', C2", C6', C6"), 77.1 (Cα), 64.41 (C2), 46.68 (C5), 26.30 (C3), 25.51 (C4); GC/MS: [ M+H] + at m/z 254.1; TLC (solvent A) R f =0.32; [α] 589 21 -54.3° (c=0.261, MeOH) [Lit. [α] 589 24 -58.8° (c=3.0, MeOH)].
Anal. Calcd for C 17 H 19 NO: C, 80.60; H, 7.50; N, 5.53. Found: C, 80.80; H, 7.64; N, 5.49.
Chiral Assay: To a magnetically stirred suspension of Step B product (sulfate salt) (30 mg, 100 μmol) in THF (1 mL) was added 1.0M aq NaOH (210 μL, 210 μmol). The mixture was stirred until all of the solid dissolved (about 15 minute), then (R)-MTPA acid chloride (27 mg, 107 μmol) was added, and the mixture stirred for 1 hour at 20° C. The reaction can be monitored by TLC (solvent B) Step B product (R f =0.05), (R,R)-derivative (R f =0.78), (R,S)-derivative (R f =0.71). After completion, the mixture was diluted into hexane (9 mL), centrifuged, and the upper, organic layer eluted through a Baker silica SPE (1 g) column (previously washed with hexane). The column was eluted with additional 8:2 (v/v) hexane/THF (5 mL). The combined eluate was analyzed by either GC (DB-23, 250° C.) to detect 0.3% of the (R,R)-derivative (19.1 minute) and 99.7% of the (R,S)-derivative (20.7 minute); or HPLC (Zorbax Si, 9:1 hexane/THF, 210 nm) to detect 0.3% of the (R,R)-derivative (k'=1.21) and 99.7% of the (R,S)-derivative (k'=1.66).
Employing the procedure substantially as described in Example 1, Step B, but substituting for the phenylmagnesium chloride used therein an equimolecular amount of the Grignard reagents depicted in Table I, there are produced the diarylmethanols also described in Table I. ##STR14##
TABLE I__________________________________________________________________________ExampleAr Yield m. p. (°C.) [α].sub.589.sup.22__________________________________________________________________________2 4-F--C.sub.6 H.sub.4 -- 90 89.5-90 -48.5° (c = 0.323, MeOH)3 4-Cl--C.sub.6 H.sub.4 -- 59 114.5-115 -37.7° (c = 0.339, MeOH)4 4-CH.sub.3 --C.sub.6 H.sub.4 -- 57 94-94.5 -43.4° (c = 0.305, MeOH)5 4-CF.sub.3 --C.sub.6 H.sub.4 --.sup.(1) 46 .sup. 280-300.sup.(2) -34.2° (c = 0.789, MeOH)6 4-t--Bu--C.sub.6 H.sub.4 -- 50 165.7-166.1 -25.1° (c = 0.389, MeOH)7 4-CH.sub.3 O--C.sub.6 H.sub.4 --.sup.(3) 53 -- -44.1° (c = 0.607, MeOH)8 3-Cl--C.sub.6 H.sub.4 --.sup.(3) 62 -- -49.1° (c = 0.804, MeOH)9 3,5-Cl.sub.2 --C.sub.6 H.sub.3 -- 68 118-119 -36.6° (c = 1.409, MeOH)10 3,5-(CH.sub.3).sub.2 --C.sub.6 H.sub.3 -- 60 97.5-98.0 -63.0° (c = 0.318, MeOH)11 2-naphthyl 64 142.5-143.5 -99.1° (c = 0.702, MeOH)__________________________________________________________________________ .sup.(1) Product is an oil. It was purified by conversion to its HCl salt recrystallization, and conversion to free base. Yield and rotation are of the purified oily product. .sup.(2) Melting point of the HCl salt. .sup.(3) Product is an oil. It was purified by liquid chromatography on silica gel. Yield and rotation are of the purified oily product.
EXAMPLE 12
Preparation of (S)-α,α-Diphenyl-2-pyrrolidinemethanol-borane complex
A 250 mL three necked flask fitted with a mechanical stirrer, nitrogen inlet tube, and teflon coated thermocouple probe, was charged with a solution of the free base product of Example 1 Step B (20.7 g, 81.7 mmol) in dry toluene (100 mL). To the stirred solution at 20° C. was added borane-methyl sulfide (10M, 10.0 mL, 100 mmol) over 5 minutes via syringe. The borane reacted immediately in an exothermic reaction (raising the internal temperature from 20° C. to 32° C.) forming a thick white precipitate. With continued stirring, the mixture was allowed to cool to room temperature (20° C.) over a 1 hour period. The mixture was filtered, and the product cake washed with dry toluene (25 mL). The product was dried in vacuo (20° C., 0.01 mBar) to constant weight. Yield 15.7 g (72%) of a white crystal line solid. m.p. 130°-132° C. (dec). 1 H NMR (CDCl 3 ) δ7.7-7.1 (m, 10H, Ar--H), 5.15 (s, 1H, --OH), 4.5 (br, 1H, --NH), 4.2 (m, 1H, C2--H), 3.25 (m, 2H, C5--H 2 ), 2.6 (m, 1H, C4--H), 2.3 (m, 1H, C4--H), 1.85 (m, 1 H, C3--H), 1.6 (m, 1H, C3--H), 2.1-0.7 (br, 3H, BH 3 ). 13 C NMR (CDCl 3 ) δ145.8, 144.5 (C1', C1"), 129.1, 128.2 (C3', C5', C3", C5"), 127.4, 127.0 (C4', C4"), 125.2, 125.1 (C2', C6', C2", C6"), 76.5 (Cα), 69.6 (C2), 55.6 (C5), 20.6 (C4), 19.9 (C3).
Anal. Calcd for C 17 H 23 BNO: C, 76.14; H, 8.64; N, 5.22. Found: C, xx.xx; H, x,xx; N, x.xx.
EXAMPLE 13
Preparation of (S)-Tetrahydro-1-methyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaborol
A 3-L, three necked flask fitted with a mechanical stirrer, nitrogen inlet tube, and teflon coated thermocouple, was charged with the sulfate salt of the product of Example 1, Step B (89.1 g, 295 mmol), THF (300 mL), and 2M aqueous NaOH (300 mL). The mixture was stirred at 20°-25° C. until all of the solid dissolved (about 0.5 hour). Toluene (1.2 L) was added, the mixture stirred an additional 0.5 hour, filtered through a medium frit sintered glass funnel, and partitioned. The upper (product) layer was washed with water (150 mL), and concentrated (1 atm) to a volume of about 500 mL. The toluene solution was cooled to 20°-25° C. and charged with trimethylboroxine (24.7 g, 197 mmol). The temperature of the mixture rose about 5° C., and a white precipitate of intermediate 5 formed. The mixture was aged 0.5 hour at 20°-25° C., then heated at reflux for 1-2 hours. Toluene (500 mL) was added, and the mixture concentrated (1 atm) to a volume of about 300 mL. The toluene addition, followed by concentration was repeated two times to insure complete removal of water and excess methylboronic acid (as trimethylboroxine). The suitability of the catalyst was determined by both capillary GC: (DB-1, 200° C.) <1% starting material (5.5 minute), >99% product (4.9 minute), and 1 H NMR: (CDCl 3 ) no starting material δ4.3 (t), trimethylboroxine δ0.45 (s), intermediate 5 δ0.35 to -0.50 (multiple B--CH 3 singlets), and/or water addition product δ-0.25 (br, B--CH 3 ). The toluene solution of oxazaborolidine (about 1.0M), stored under an atmosphere of N 2 protected from moisture, was used "as is" as a catalyst for the enantioselective reduction of ketones with borane.
For analysis, a portion of the toluene solution (10.0 mL) was concentrated in vacuo (50° C., 0.001 mBar) to afford 2.77 g of product as a white solid: mp 79°-81° C. [Lit. mp 74°-87° C.]; IR (CCl 4 ) 2960, 2880, 1440, 1330, 1310, 1235, 1000 cm -1 ; 1 H NMR (0.2M in CDCl 3 ) δ7.65-7.15 (m, 10H, Ar--H), 4.4 (dd, J=5.8, 10.0 Hz, 1H, C3a--H), 3.45-3.30 (m, 1H, C6--H), 3.15-3.00 (m, 1H, C6--H), 1.90-1.55 (m, 3H, C4--H, C5--H 2 ), 0.95-0.75 (m, 1H, C4--H), 0.40 (s, 3H, BCH 3 ); 11 B NMR (0.2M in CDCl 3 ) δ34.3; 13 C NMR (0.2M in CDCl 3 ) δ147.6, 144.0 (C1', C1"), 128.2, 127.7 (C3', C3", C5', C5"), 127.1, 126.6 (C4', C4"), 126.3, 126.2 (C2', C2", C6', C6"), 87.8 (C3), 72.7 (C3a), 42.9 (C6), 30.2 (C4), 26.4 (C5), -5.6 (br, B--CH 3 ). FAB/MS (DTT/DTE matrix): [M+H] + at m/z 278.1. Isotopic cluster consistent with the presence of one boron.
Anal. Calcd for C 18 H 20 BNO: C, 78.00; H, 7.27; N, 5.05. Found: C, 77.81; H, 7.37; N, 4.91.
EXAMPLE 14
Preparation of Intermediate 5
To a magnetically stirred solution of the free base product of Example 1, Step B (5.06 g, 20.0 mmol) in dry toluene (20 mL) at 20° C. was added trimethylboroxine (1.67 g, 13.3 mmol). The reaction was exothermic, raising the temperature to 33° C. The solution was allowed to cool to 20° C., then aged at that temperature for 1 hour. The resultant solid was isolated by filtration. The solid was dried in vacuo (45° C., 0.1 mBar) to afford 6.07 g (90%) of intermediate 5. An analytical sample was prepared by recrystallization from EtOAc: mp 147°-148° C.; IR (solid) 3435, 3270, 3066-2885, 1596, 1492, 1447, 1384, 1302, 1247, 1141, 1046, 1030, 1015, 1006, 762, 752, 717, 701; 1 H NMR (CD 3 CN, major diasteromer) δ7.66 (m, 2H, o--Ar--H), 7.47 (m, 2H, o--Ar--H), 7.3-7.1 (overlapping m, 6H, Ar--H), 6.37 (s, 1H, B--OH), 5.13 (br, 1H, NH), 4.68 (dt, J=11.1, 6.5, 1H, C3a--H), 3.39 (m, 1H, C6--H), 2.99 (m, 1H, C6--H), 1.9-1.7 (overlapping m, 3H, C5--H 2 , C4--H), 1.44 (m, 1H, C4--H), 0.09 (s, 3H, --OB(OH)CH 3 ), -0.49 (s, 3H, B1--CH 3 ); 11 B NMR (CDCl 3 , major diasteromer) δ30.4 (--OB(OH)CH 3 ), 7.8 (B1); 13 C NMR (CD 3 CN, major diasteromer) δ148.4, 147.9 (C1', C1"), 129.0, 128.8 (C3', C5', C3", C5"), 127.7, 127.2 (C4', C4"), 126.8, 126.1 (C2', C6', C2", C6"), 83.6 (C3), 68.6 (C3a), 45.6 (C6), 28.7 (C4), 24.6 (C5), 7.0 (v br, B1--CH 3 ), -0.2 (v br, --OB(OH)C 3 ). FAB/MS (DTT/DTE matrix): [M+H] + at m/z 338.2. Isotopic cluster consistent with the presence of two borons.
Anal. Calcd for C 19 H 25 B 2 NO 3 : C, 67.71; H, 7.48; N, 4.16. Found: C, 67.59; H, 7.47; N, 4.15.
Employing the procedure substantially as described in Example 13, but substituting for the diphenylmethanol used therein, comparable amounts of the diarylmethanols described in Table II, there were produced the B-methyl oxazaborolidines also described in Table II: ##STR15##
TABLE II______________________________________Example Ar Purity (%)______________________________________15 4-F--C.sub.6 H.sub.4 --.sup.(1) 9816 4-Cl--C.sub.6 H.sub.4 --.sup.(1) 9917 4-CH.sub.3 --C.sub.6 H.sub.4 -- 9918 4-CF.sub.3 --C.sub.6 H.sub.4 --.sup.(1) 9919 4-t-Bu-C.sub.6 H.sub.4 -- 9920 4-CH.sub.3 O--C.sub.6 H.sub.4 -- 9921 3-Cl--C.sub.6 H.sub.4 -- 9922 3,5-Cl.sub.2 --C.sub.6 H.sub.3 -- 9923 3,5-(CH.sub.3).sub.2 --C.sub.6 H.sub.3 9924 2-naphthyl 99______________________________________ .sup.(1) Reaction run in benzene.
EXAMPLE 25
Preparation of (S)-Tetrahydro-1-n-butyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaborole
A solution of the free base product from Example 1, Step B (20.1 g, 79.4 mmol) and tri-n-butylboroxine (6.66 g, 26.5 mmol) in toluene (200 mL) was aged 0.5 hour at 20°-25° C., then heated at reflux for 16 hours using a Dean-Stark trap for water removal. The solution was concentrated (1 atm) to a volume of about 70 mL. The suitability of the catalyst was determined by both capillary GC: (DB-1, 200° C.) <0.1% tri-n-butylboroxine (1.3 minute), <1% starting material (5.7 minute), >98% product (9.7 minute), and 1 H NMR: (CDCl 3 ) no starting material δ4.25 (t). Based on the final volume of 70 mL, the concentration of the oxazaborolidine was calculated to be 1.13M. The toluene solution, stored under an atmosphere of N 2 protected from moisture, was used "as is" as a catalyst for the enantioselective reduction of ketones with borane.
For analysis, a portion of the toluene solution (5.00 mL) was concentrated in vacuo (50° C., 0.001 mBar) to afford 1.80 g of the product as a colorless oil: IR (CCl 4 ) 3060, 3020, 2960, 2930, 2880, 1480, 1440, 1240, 1000 cm -1 ; 1 H NMR (0.2M in CDCl 3 ) δ7.65-7.45 (m, 2H, Ar--H), 7.45-7.05 (m, 8H, Ar--H), 4.35 (dd, J=5.6, 9.9 Hz, 1H, C3a--H), 3.45-3.30 (m, 1H, C6--H), 3.15-3.00 (m, 1H, C6--H), 1.90-1.25 (m, 7H, C4--H, C5--H 2 , C2'--H 2 , C3'--H 2 ), 1.05-1.70 (m, 6H, C4--H, C1'--H 2 , C4'--H 3 ); 11 B NMR (CDCl 3 ) δ34.3; .sup. 13 C NMR (0.2M in CDCl 3 ) δ147.8, 144.1 (C1", C1'"), 128.1, 127.7 (C3", C3'", C5", C5'"), 127.1, 126.5 (C4", C4'"), 126.22, 126.16 (C2", C2'", C6", C6'"), 87.4 (C3), 73.1 (C3a), 42.8 (C6), 30.2 (C4), 26.9 (C2'), 26.5 (C5), 25.7 (C3'), 14.0 (C4').
Anal. Calcd for C 21 H 26 BNO: C, 79.01; H, 8.21; N, 4.39. Found: C, 78.58; H, 8.37; N, 4.37.
EXAMPLE 26
Preparation of (S)-Tetrahydro-1,3,3-triphenyl-1H,3H-pyrrolo-[1,2-c][1,3,2]oxazaborole
A solution of the free base product of Example 1, Step B (10.3 g, 40.7 mmol) and triphenylboroxine (4.25 g, 13.6 mmol) in toluene (100 mL) was aged 0.5 hour at 20°-25° C., then heated at reflux for 16 hours using a Dean-Stark trap for water removal. The solution was concentrated (1 atm) to a volume of 47 mL. The suitability of the catalyst was determined by both capillary GC: (DB-1, 160° C. for 3 minute, then 10° C./minute to 300° C.) <0.1% benzophenone (2.6 minute), <1% starting material (7.5 minute), <1% triphenylboroxine (10.8 minute), >98% oxazaborolidine product (14.2 minute), and 1 H NMR: (CDCl 3 ) no starting material δ4.25 (t). Based on the final volume of 47 mL, the concentration of oxazaborolidine product was calculated to be 0.87M. The toluene solution, stored under an atmosphere of N 2 protected from moisture, was used "as is" as a catalyst for the enantioselective reduction of ketones with borane.
For analysis, a portion of the toluene solution (5.00 mL) was concentrated in vacuo (50° C., 0.001 mBar) to afford 1.48 g of the product as a colorless glass: IR (CCl 4 ) 3060, 3020, 2960, 2870, 1595, 1445, 1300, 1000 cm -1 ; 1 H NMR (0.2M in CDCl 3 ) δ8.05-7.95 (m, 2H, Ar--H), 7.70-7.60 (m, 2H, Ar--H), 7.55-7.15 (m, 11H, Ar--H), 4.65 (dd, J=5.5, 9.7 Hz, 1H, C3a--H), 3.70-3.55 (m, 1H, C6--H), 3.45-3.30 (m, 1H, C6--H), 2.05-1.75 (m, 3H, C4--H, C5--H 2 ), 1.05-0.90 (m, 1H, C4--H); 11 B NMR (CDCl 3 ) δ30.8; 13 C NMR (0.2M in CDCl 3 ) δ147.4, 143.8 (C1", C1'"), 134.6 (C2', C6'), 130.3 (C4'), 128.2, 127.77 (C3", C3'", C5", C5'"), 127.85 (C3', C5'), 127.2, 126.7 (C4", C4'"), 126.41, 126.35 (C2", C2'", C6", C6'"), 87.7 (C3), 74.4 (C3a), 43.8 (C6), 30.0 (C4), 27.6 (C5).
Anal. Calcd for C 23 H 22 BNO: C, 81.43; H, 6.54; N, 4.13. Found: C, 81.35; H, 6.56; N, 4.12.
Employing the procedure substantially as described in Example 26, but substituting for the triphenylboroxine used therein, comparable amounts of triarylboroxines described in Table III, there were produced the B-aryl oxazaborolidines also described in Table III: ##STR16##
TABLE III______________________________________Example R Purity (%)______________________________________27 4-F--C.sub.6 H.sub.4 -- 9828 4-Cl--C.sub.6 H.sub.4 -- 9729 4-CH.sub.3 --C.sub.6 H.sub.4 -- 9930 4-CF.sub.3 --C.sub.6 H.sub.4 -- 9731 4-CH.sub.3 O--C.sub.6 H.sub.4 -- 9732 2,4,6-(CH.sub.3).sub.3 --C.sub.6 H.sub.2 -- 97______________________________________
EXAMPLE 33
Preparation of (S)-Tetrahydro-1-methyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaborole--borane complex
To a mechanically stirred solution of the oxazaborolidine decribed in Example 13 (1.28M in toluene) (20.0 mL, 25.6 mmol) at 20° C. was added borane-methyl sulfide (10M, 5.0 mL, 50 mmol). The solution was stirred at 20° C. for 12 hours with a nitrogen sweep to remove dimethyl sulfide. The thick white mixture was filtered, and the product cake washed with dry toluene (10 mL). The product was dried in vacuo (20° C., 0.01 mBar) to afford 6.04 g (81% yield) of a white crystalline solid. m.p. 122°-130° C. (dec). 1 H NMR (CDCl 3 ) δ7.6 (m, 2H, Ar--H), 7.15-7.40 (m, 8H, Ar--H), 4.65 (t, J=7.9 Hz, 1H, C3a--H), 3.4 (m, 1H, C6--H), 3.2 (m, 1H, C6--H), 1.9 (m, 2 H, C5--H 2 ), 1.7 (m, 1H, C4--H), 1.3 (m, 1H, C4--H), 2.1-0.8 (very br, 3H, BH 3 ), 0.78 (s, 3H, B--CH 3 ). 13 C NMR (CDCl 3 ) δ144.6, 143.5 (C1', C1"), 128.3, 128.2 (C3', C5', C3", C5"), 127.4, 127.1 (C4', C4"), 125.4, 125.0 (C2', C6', C2", C6"), 90.6 (C3), 76.2 (C3a), 57.7 (C6), 31.4 (C4), 25.0 (C5).
Anal. Calcd for C 18 H 23 B 2 NO: C, 74.29; H, 7.97; N, 4.81. Found: C, xx.xx; H, x.xx; N, x.xx.
The following reaction scheme is described in Example 34, which illustrates the utility of the oxazaborolidine catalysts, particularly in Step E describing the reduction of 9 to 10. ##STR17##
EXAMPLE 34
S-(+)-5,6-Dihydro-4-(2-methylpropyl)amino-4H-thieno-[2,3-b]-thiopyran-2-sulfonamide-7,7-dioxide
Steps A and B: Preparation of 3-(2-thienylthio)propanoic acid (7)
In a 2-L, three-neck round-bottom flask fitted with a thermometer, nitrogen inlet, mechanical stirrer and addition funnel was placed thiophene (64 mL, 799 mmol; Caution: stench) and sieve dried THF (400 mL, residual water ≦120 μg/mL). The solution was cooled to 0°-5° C. and 1.6M n-butyllithium (470 mL, 751 mmol) was added at such a rate as to maintain the temperature at <20° C. The reaction was stirred for 1 hour at 0°-5° C., and was used immediately in the next sequence. To the cooled reaction mixture (0°-5° C.) was added sulfur (24 g, 750 mmol) portionwise while maintaining the temperature at <20° C. The reaction was stirred for an additional 2.0 hours at 0°-5° C. after which nitrogen-purged water (300 mL) was added at such a rate as to maintain the temperature at <18° C. The addition of sulfur was highly exothermic. (Note: the 2-mercaptothiophene and its anion (6) can air-oxidize to the corresponding disulfide. Therefore, solutions of 6 must be deoxygenated and stored under a nitrogen atmosphere). Solids may form initially upon addition of water to the solution of 6 but eventually dissolve. The solution of 6 was titrated for total base. The yield of thiophene to 6 based on titration was 98%.
In a 1-L, three-neck, round-bottom flask fitted with an addition funnel, thermometer, nitrogen sweep and mechanical overhead stirrer was prepared a solution of potassium carbonate (46.5 g, 337 mmol) in nitrogen-purged water (85 mL). To this solution was added solid 3-bromopropionic acid (116 g, 736 mmol) at such a rate as to control foaming (CO 2 evolution). The mixture was stirred until a clear solution was obtained. The temperature increased from 23° C. to 50° C. during the dissolution of potassium carbonate. (Caution: foaming occurs during the addition). The solution of 6 was cooled to 10° C. and the aqueous solution of potassium 3-bromopropionate was added at such a rate as to maintain the temperature at 0°-5° C. The reaction was stirred for 24 hours at ambient temperature. The layers were separated and the aqueous layer was washed twice with toluene (100 mL portions) to remove neutral organic impurities. The aqueous layer was then cooled to 10° C. and stirred with toluene (300 mL) as aqueous HCl (125 mL, 6N) was added, maintaining the temperature at <14° C. (pH<1). The organic layer was separated and the aqueous layer extracted with additional toluene (300 mL). The organic layers were combined and dried azeotropically under vacuum to a volume of 500 mL and residual water content of ≦2.5 mg/mL. The solution was stored at 0°-5° C. overnight. A small amount of the carboxylic acid was isolated and characterized as its tert-butylammonium salt: m.p. 110°-112° C. IR (CHCl 3 ): 3400-2300 br s (OH), 2980 m, 2630 m, 2200 w, 1635 m, 1580 br s (C═O), 1480 w, 1390 s, 1300 m, 1270 m, 990 w, 930 w, 850 w. 1 H NMR: δ8.36 (br s, NH 3 + ), 7.29 (d, J=5.4, H 5' ), 7.07 (d, J=3.5, H 3' ), 6.93 (dd, J=5.4, 3.5, H 4' ), 2.99 (m, C 2 H 2 ), 2.43 (m, C 3 H 2 ), 1.27 (s, C(CH 3 ) 3 ). 13 C NMR: δ177.9 (C 1 ), 134.5 (C 2' ), 133.5, 129.0, 127.4 (C 3' , C 4' , C 5' ), 50.6 (C(CH 3 ) 3 ), 38.4, 35.6 (C 2 , C 3 ), 27.8 (C(CH 3 ) 3 ).
Anal. Calcd for C 11 H 19 NO 2 S 2 : C, 50.54; H, 7.33; N, 5.36. Found: C, 50.53; H, 7.12; N, 5.27.
Step C: Preparation of 5,6-Dihydro-4H-thieno[2,3-b]-thiopyran-4-one (8)
In a 2-L three-neck round-bottom flask fitted with an overhead mechanical stirrer, thermometer, addition funnel, reflux condenser, and nitrogen bubbler vented through an acid-vapor scrubber was placed the toluene solution of 7 (130.7 g, 695 mmol). The reaction mixture was brought to an initial temperature of 20° C. and trifluoroacetic anhydride (161 g, 765 mmol) was added over 5 minutes to the stirred solution of 7. The reaction was then heated to 35°-38° C. and stirred for about 1.5 hours. The reaction was then slowly added to water (500 mL) maintaining the temperature at <25° C. A pH probe was placed in the vessel and the mixture was titrated to pH 7.0 with 50% sodium hydroxide (123 g, 1.53 mole). The layers were separated and the aqueous phase was extracted once with toluene (200 mL). The combined organic extracts were then concentrated under vacuum (43 mbar) to a volume of 200 mL and then diluted to 1.2 L with ethyl acetate for the next step (oxidation). A small sample was chromatographed to obtain the following data: R f =0.29 (85:15 hexane:ethyl acetate). m.p. 61°-62° C. IR (CHCl 3 ): 3120 w, 3090 w, 3010 m, 2930 w, 1660 s (C═O), 1500 m, 1390 s, 1315 w, 1280 w, 1265 m, 1190 w, 1035 w, 890 w. 1 H NMR: δ7.42 (d, J=5.4, H 2 ); 6.98 (d, J=5.4, H 3 ); 3.33 (m, C 5 H 2 ); 2.82 (m, C 6 H 2 ). 13 C NMR: δ188.9 (C 4 ), 150.9, 135.0 (C 3a , C 7a ), 126.1, 121.8 (C 2 , C 3 ), 38.1 (C 6 ), 30.0 (C 5 ).
Anal Calcd for C 7 H 6 OS 2 : C, 49.39; H, 3.55; S, 37.66. Found: C, 49.56; H, 3.58; S, 37.68.
Step D: Preparation of 5,6-Dihydro-4H-thieno[2,3-b]-thiopyran-4-one-7,7-dioxide (9)
The ethyl acetate/toluene solution of ketone 8 (118 g, 765 mmol in 1.2 L of 5:1 v:v EtOAc/toluene) was charged to a 5-L three-neck round-bottom flask equipped with an overhead mechanical stirrer, 250-mL pressure-equalizing dropping funnel, and thermocouple temperature probe. The mixture was stirred and water (35 mL) was added to saturate the organic phase. A solution of sodium tungstate dihydrate (11.7 g, 77 mmol) dissolved in water (35 mL) was then added (Caution: there is an induction period of several minutes before an exotherm). The mixture was heated to 35° C. and hydrogen peroxide (30%, 250 mL, 2.43 mole) was added over 45 minutes. The temperature of the reaction was allowed to rise to 55°-58° C. and was maintained there, initially with cooling and subsequently with heating. The reaction temperature was maintained at 55°-58° C. until judged complete by HPLC: column A, (1 mL/minute, 50:50 0.01M H 3 PO 4 in H 2 O:CH 3 CN, 240 nm) R t (8) 6.18 minutes, (9) 4.07 minutes. On completion the mixture was cooled to 0°-5° C. and excess hydrogen peroxide was decomposed by the slow addition of aqueous sodium sulfite (205 g, 1.63 mole dissolved in 700 mL water). The temperature of the reaction mixture was maintained at <20° C. When the reaction mixture tested negative for peroxide to acidified starch-iodide paper, the layers were separated. The upper organic layer was concentrated under vacuum at 45° C. bath temperature to a volume of 400 mL. Hexanes (400 mL) were then added over about 10 minutes and the batch was aged for one hour. The product was filtered, washed with hexanes, and dried under vacuum at 60° C. with a nitrogen sweep to constant weight. The yield of crude ketosulfone 9 was 113 g (76% from 3-bromopropionic acid). Crude ketosulfone was then recrystallized from methanol using the following procedure. Crude ketosulfone (113 g) was dissolved in anhydrous methanol (3 L) at 55°-60° C. The solution was cooled to 40° C. and 10 g of Calgon ADP carbon was added. The mixture was aged at 40° C. for a minimum of 4 hours. The batch was then filtered warm at 40° C. through a well-washed pad of SuperCel. The filter cake was washed with methanol (2×500 mL) at 40° C. and the filtrates were combined. The batch was then concentrated under vacuum to a volume of 500 mL and aged at 0°-5° C. for 4 hours. Crystallization ensued during concentration. The batch was filtered, washed with 75 mL cold methanol, sucked dry under nitrogen, and dried under vacuum (100 Torr) at 80° C. with a nitrogen sweep for 12 hours. The recovery yield was 100 g (89%) assayed δ99.6 wt % by HPLC against an external stand ard. R f =0.30 (dichloromethane). m.p. 121°-121.5° C. IR (CHCl 3 ): 3120 w, 3100 w, 3020 m, 1690 s (C═O), 1500 w, 1410 m, 1390 m, 1330 s (SO 2 ), 1310 m, 1285 m, 1260 m, 1190 s, 1155 s (SO 2 ), 1130 m, 1090 m, 860 s, 820 w. 1 H NMR: δ7.60 (d, J=5.1, H 2 ); 7.50 (d, J=5.1, H 3 ); 3.76 (m, C 5 H 2 ); 3.36 (m, C 6 H 2 ). 13 C NMR: δ186.3 (C 4 ), 147.2 (C 3a ), 139.3 (C 7a ), 130.2 (C 2 ), 126.3 (C 3 ), 52.8 (C 6 ), 37.0 (C 5 ). MS (EI, 70 eV): 202 (M + , 35), 174 (38), 138 (15), 110 (100), 84 (30), 82 (25).
Anal. Calcd for C 7 H 6 O 3 S 2 : C, 41.57; H, 2.99; S, 31.70. Found: C, 41.49; H, 3.02; S, 31.60.
Step E: Preparation of R-(+)-5,6-Dihydro-4H-thieno-[2,3-b]-thiopyran-4-ol-7,7-dioxide (10)
Ketosulfone 9 (50.0 g, 0.247 moles) was dissolved in tetrahydrofuran (700 mL) over 4 Å molecular sieves (20 g) and occasionally swirled until the residual water content was <40 μg/mL (about 2 hours). A 2-L three-neck round bottom flask fitted with a mechanical stirrer, nitrogen inlet tube, 500-mL addition funnel and teflon coated thermocouple probe, was charged with 9 (decanted from the sieves). To the solution was added oxazaborolidine catalyst (R=CH 3 , Ar=C 6 H 5 ) (14.4 mL of a 0.86M solution in toluene). The resulting solution was cooled to -15° C. In a separate vessel borane-methyl sulfide (17.3 mL) was dissolved in dry tetrahydrofuran (297 mL; residual water <40 μg/mL). The borane-methyl sulfide solution was placed in the addition funnel and added to the ketosulfone/catalyst solution at a rate to maintain the internal temperature at -15° C. (about 30 minutes). After all of the borane was added, the reaction was aged for 30 minutes. An easily stirred precipitate usually forms during the age. The reaction was quenched by the cautious addition of 10 mL of methanol (Caution: there was a significant induction period (1-2 minutes) before hydrogen was evolved after the initial methanol was added) maintaining the temperature at -10° C. After hydrogen evolution subsides, methanol (365 mL) was added. The reaction becomes homogeneous during the quench. After complete addition of methanol, the reaction mixture was warmed to 20° C. and stirred for 12 hours. The resulting solution was concentrated at atmospheric pressure to about 125 mL. Methanol (375 mL) was added and the resulting solution was concentrated at atmospheric pressure to 125 mL to remove any remaining volatile boron species.
Amberlyst 15 resin (56 g, 100 mL dry) was suspended in methanol (100 mL). (Caution: the slurry exotherms to about 40° C. without external cooling and expands on wetting to about 1.5 times its initial volume). The slurry was poured into a 2.5×30 cm column and eluted with 1 L of ammonium hydroxide (15M) in methanol (6 vol %, about 1M) until the eluate was basic (pH about 11 when diluted 1:1 with water). The initial brown eluate was discarded. The column was eluted with methanol (about 500 mL) until the eluate was neutral. The methanol solution of (R)-hydroxy sulfone (about 50 g) and (S)-diphenylprolinol (3.13 g) was filtered through a pad of SuperCel. The cake was washed with methanol (2×50 mL) and the combined filtrates brought to a volume of 500 mL (10 mL/g) with methanol. The filtered methanol solution was eluted through the column containing Amberlyst 15 (NH 4 + ) at 3.8 mL/minute collecting 38 mL fractions. The column was rinsed with methanol (380 mL) to remove all of the product hydroxysulfone. The column was then eluted with 94:6 (v/v) methanol/15M aqueous ammonia (400 mL) to elute diphenylprolinol. Fractions 3-21 containing (R)-hydroxysulfone (95:5 R:S, 49 g (98%), contaminated with less than 0.4% diphenylprolinol) were combined and concentrated (recrystallization of this material from hexane/ethyl acetate only serves to lower enantiomeric purity). Addition of tetrahydrofuran (500 mL) followed by concentration to 250 mL was repeated twice. Tetrahydrofuran was added to generate a solution of 10 in a total volume of 500 mL for use in the next reaction. Fractions 29-33 containing (S)-diphenylprolinol (<1:99 R:S, 3.0 g) were combined and concentrated to afford a crystalline solid. The progress of the column can be monitored by HPLC: column A (1 mL/minute, 60:40 0.01M KH 2 PO 4 in H 2 O:CH 3 CN) R t (9) 4.78 minutes (240 nm), (10) 3.30 minutes (240 nm), (diphenylprolinol) 5.60 minutes (210 nm). A small sample was chromatographed to obtain characterization data: R f =0.07 (60:40 hexane:ethyl acetate). [α] 589 21 =+16.4° (c 0.210, MeOH). m.p. 89°-90° C. IR (CHCl 3 ): 3600 w (OH), 3550-3400 br w (OH), 3110 w, 3010 m, 2940 w, 1520 w, 1400 m, 1305 s (SO 2 ), 1285 s, 1180 w, 1145 s (SO 2 ), 1125 s, 1100 w, 1160 m, 1140 m, 970 w, 915 w, 890 w, 845 w, 825 m. 1 H NMR: δ7.59 (d, J=5.1, H 2 ), 7.12 (d, J=5.1, H 3 ), 4.91 (ddd, J=10.0, 5.9, 1.5, H 4 ), 3.62 (m, H 6 ), 3.31 (m, H 6 ), 2.75 (m, H 5 ), 2.55 (m, H 5 , OH). 13 NMR: δ144.9 (C 3a ), 135.9 (C 7a ), 130.5 (C 2 ), 127.0 (C 3 ), 63.5 (C 4 ), 49.1 (C 6 ), 31.0 (C 5 ).
Anal. Calcd for C 7 H 8 O 3 S 2 : C, 41.16; H, 3.95; S, 31.39. Found: C, 41.23; H, 3.93; S, 31.24.
Chiral Assay: To alcohol 10 (20 mg) in dry dichloromethane (2 mL) was added N,N-dimethylaminopyridine (12 mg, 1.0 equiv), triethylamine (14 mL, 10 mg, 3.0 equiv) and (R)-(+)-a-methoxy-a-(trifluoro-methyl)phenylacetic acid chloride (Mosher acid chloride, 27 mg, 21 mL, 1.1 equiv, see General of Experimental Section). The mixture was stirred for 1-5 hours, as judged by TLC (EM Si-60, 6:4 hexane/EtOAc, R f alcohol 10=0.10, R f ester=0.60). The reaction mixture was diluted with hexane (8 mL) and centrifuged (5 minutes). The resulting clear yellow solution was eluted through a Baker Silica SPE (1 g) column (previously washed with 5 mL of hexane). The initial eluate was discarded, and 6:4 hexane/EtOAc (10 mL) was eluted and collected. The latter eluate was then analyzed by capillary GC on column A: (15 psi, 200° C., isothermal) R t ((R,R)-Mosher ester (major), 10.0 minutes; (R,S)-Mosher ester (minor), 10.4 minutes. Enantiomeric purity: >95:5.
Steps F and G: Preparation of S-5,6-Dihydro-N-(2-methylpropyl)-4H-thieno[2,3-b]-thiopyran-4-amine-7,7-dioxide (12)
A 3-L three-neck flask fitted with a mechanical stirrer, nitrogen inlet tube, 500-mL addition funnel and teflon coated thermocouple probe was charged with a slurry of sodium acetylide in xylene/light mineral oil (Aldrich, 71.9 g, 0.270 mol of an 18% slurry) and was well mixed with 400 mL of tetrahydrofuran. Hydroxysulfone 10 (50.0 g, 0.245 moles) dissolved in dry tetrahydrofuran (500 mL, see above; residual water content should be <100 μg/mL) and placed in the addition funnel. The solution was cooled to 15° C. and the solution of 10 was added to the sodium acetylide over about 5 minutes. (Caution: sodium acetylide is moisture sensitive and generates acetylene upon addition of water). The resulting suspension was stirred at 20° C. for 2 hours. During the age, the fine slurry of sodium acetylide was converted to the easily stirred, coarse, crystalline sodium salt of the hydroxysulfone. (The deprotonation can be monitored by removing a 1 mL aliquot and adding it to excess toluenesulfonyl chloride (45 mg, 0.24 mmol) in 1 mL of tetrahydrofuran and monitoring by TLC: 60:40 hexane:ethyl acetate; R f : hydroxysulfone 10, 0.07; tosylate 11, 0.37). The resulting slurry was cooled to -15° C. Toluenesulfonyl chloride (51.3 g, 0.269 mol) was dissolved in 250 mL of tetrahydrofuran and placed in the addition funnel. The toluenesufonyl chloride/tetrahydrofuran solution was added to the sodium salt at a rate to maintain the internal temperature below -10° C. (about 10 minutes). The resulting mixture was aged at -10° C. for 2 hours. The tosylation can be followed by TLC (60:40 hexane:ethyl acetate; R f : tosylate 11, 0.37; hydroxysulfone 10, 0.07). The sodium salt of the hydroxysulfone dissolved during the age and the reaction usually turned dark green. (Note: tosylate 11 should not be isolated since it readily hydrolyzes to racemic 10 in water). Dry (residual water <100 μg/mL) isobutylamine (250 g, 340 mL, 3.43 mol) was added over 5 minutes. The resulting mixture was warmed to 20° C. and aged for 14 hours. (This reaction was monitored by TLC: 60:40 hexane:ethyl acetate; R f : tosylate 11, 0.37; amine 12, 0.25). The resulting mixture was cooled to -15° C. and aqueous hydrochloric acid (1.54 L, 2N) was added at a rate to maintain the internal temperature at or below 5° C. (about 30 minutes). The resulting pH was about 2.5. The solution was concentrated to about 1.6 L to remove most (90%) of the tetrahy drofuran and extracted with isopropyl acetate (2×600 mL). The aqueous phase was cooled to 0° C. and sodium hydroxide (120 mL, 5N) was added at a rate to maintain the internal temperature below 5° C. (about 5 minutes). The resulting pH was about 10 and the reaction mixture became cloudy upon addition of sodium hydroxide. The resulting mixture was extracted twice with isopropyl acetate (600 mL). The organic layers were combined and concentrated to about 120 mL. Isopropanol (600 mL) was added and the mixture was concentrated to 100 mL. A second flush was performed to remove the isopropyl acetate. (Solubility of amine 12 in isopropa nol: 2.5 mg/mL at -20° C.; 7.3 mg/mL at 0° C.; 28.3 mg/mL at 20° C.; 151 mg/mL at 45° C.). Isopropanol was added to bring the volume to about 1 L and the resulting solution was warmed to 55°-60° C. and Calgon ADP (5 g) decolorizing carbon was added. The mixture was stirred at 50° C. for 4 hours. The resulting mixture was filtered (at 50° C.) through prewashed SuperCel. The filtered solution was concentrated to 0.86 L (14 mL/g amine) and allowed to cool slowly to room temperature. The resulting suspension was cooled to 0° C. and aged for 2 hours. The suspension was filtered, washed twice with 150 mL of 0° C. isopropanol and dried in vacuo at 45° C. for 12 hours to yield 47 g (73%) of amine 12 (R=2-methylpropyl) as off white crystals.
Data for 12: R f =0.25 (60:40 hexane:ethyl acetate). [α] 589 22 =-8.68° (c 0.316, MeOH). m.p. 86°-86.5° C. IR (CHCl 3 ): 3110 w, 3010 m, 2960 m, 2950 sh, 2900 w, 2870 w, 2830 w, 1520 w, 1460 m, 1400 m, 1365 w, 1305 s (SO 2 ), 1280 m, 1140 s (SO 2 ), 1090 m, 1055 w, 890 w, 850 w, 830 w. 1 H NMR: δ7.53 (d, J=5.0, H 2 ), 7.08 (d, J=5.0, H 3 ), 3.91 (dd, J=6.3, 4.1, H 4 ), 3.68 (ddd, J=13.6, 9.8, 2.8, H 6 ), 3.27 (ddd, J=9.3, 8.8, 2.6, H 6 ), 2.55 (m, C 5 H 2 , C 1' H 2 ), 1.68 (nine lines, J=6.6), 0.92 (d, J=6.8). 13 C NMR: δ146.0 (C 3a ), 135.6 (C 7a ), 129.7 (C 2 ), 127.1 (C 3 ), 55.0 (C 1' ), 52.6 (C 4 ), 49.6 (C 6 ), 28.8 (C 2' ), 27.8 (C 5 ), 20.6, 20.5 (2×CH 3 ).
Anal. Calcd for C 11 H 17 NO 2 S 2 : C, 50.94; H, 6.61; N, 5.40; S, 24.72. Found: C, 51.00; H, 6.64; N, 5.30; S, 24.50.
Chiral Assay: To amine 12 (10 mg) in dry ethyl acetate (1 mL) was added trifluoroacetic anhydride (20 mL). The mixture was stirred for 1-5 minutes, as judged by TLC (EM Si-60, 6:4 hexane/EtOAc, R f : amine 12, 0.30; amide, 0.50). The reaction mixture was concentrated to dryness and then diluted with tetrahydrofuran (2 mL). The resulting clear yellow solution was eluted through a Baker quaternary amine SPE (1 g) column (previously washed with 5 mL of isopropanol). The eluate was collected, and 88:11:1 hexane/tetrahydrofuran/isopropanol (20 mL) was eluted and collected. The eluate was then analyzed by normal phase HPLC (250 nm): column B (2.0 mL/minute, 88:11:1 hexane:tetrahydrofuran: isopropanol, isocratic): R t : (R)-TFA-12 10.65 minutes; (S)-TFA-12 12.82 minutes. Enantiomeric purity >99:1.
Step H: Preparation of S-(+)-5,6-Dihydro-4-(2-methylpropyl)amino-4H-thieno[2,3-b]thiopyran-2-sulfonamide-7,7-dioxide monohydrochloride hemihydrate (13)
A 1-L round-bottom flask fitted with a mechanical stirrer, nitrogen inlet and septum was charged with fuming sulfuric acid (12-20% SO 3 in H 2 SO 4 , 125 mL). (Caution: fuming sulfuric acid (oleum) is extremely corrosive). The solution was cooled to -15° C. and amine 12 (R=2-methylpropyl) (25 g, 96.4 mmol) was added portionwise at a rate to maintain the temperature <0° C. (Caution: the addition is exothermic). After stirring the resultant solution for 2 hours at 5°-8° C., thionyl chloride (375 mL, 611 g, 5.14 mol) was added and the mixture was refluxed for 3 hours. The thionyl chloride was removed by distillation and the resulting oil was cooled to 0° C. A 5-L round-bottom flask fitted with a mechanical stirrer, 250-mL pressure equalizing addition funnel (with a teflon tube attached to the bottom that reached below the surface of the contained liquid) and nitrogen inlet was charged with concentrated aqueous ammonia (800 mL) and tetrahydrofuran (800 mL) and cooled to -15° C. The addition funnel was charged with the sulfuric acid solution of the sulfonyl chloride. The sulfuric acid solution was slowly added (subsurface) to the ammonia mixture at a rate to maintain the temperature below 0° C. (about 1 hour). (Caution: addition of strong acid to strong base is exothermic and spattering may occur). After complete addition, the resulting mixture was stirred at 0° C. for 30 minutes. The resulting pH was 10. The resulting suspension was filtered and the filter cake washed twice with tetrahydrofuran (600 mL). The filtrate was concentrated to remove tetrahydrofuran and extracted twice with ethyl acetate (600 mL). The organic layers were combined, concentrated to 375 mL and stirred well as concentrated hydrochloric acid (12 mL, 145 mmol) was slowly added. The mixture was concentrated under vacuum at 45° C. (bath temperature) to remove water, replacing ethyl acetate as necessary, until a solution with a water content of <0.1 mg/mL was attained at a volume of about 350 mL. The crystallized mixture was allowed to cool and stirred at ambient temperature overnight. The slurry was filtered and washed with two bed volumes of ethyl acetate. The white solid was dried under vacuum at 45° C. to afford 26 g of 13 (R=2-methylpropyl) hydrochloride. The salt could be recrystallized from water as follows: 13 (R=2-methylpropyl) hydrochloride (25 g, 73 mmol) was dissolved in water (50 mL) at 90° C. The mixture was well stirred and activated carbon (Darco KB, 2.5 g) was added to the hot mixture. After stirring for 2 hours, the mixture was filtered hot (85°-90° C.) through a washed bed of SuperCel and the filter cake washed with 10 mL of boiling water. The combined filtrate and wash was allowed to slowly cool to 40°-50° C. and held at 40°-50° C. until crystallization occurred. After stirring for 1 hour at 55° C. after crystallization occurred, the mixture was cooled to 3° C. and aged for 1 hour. The resulting mixture was filtered and the filter cake washed with cold water (10 mL). The product was dried under vacuum at 45° C. with a nitrogen sweep to afford 21 g (71%) of 13 (R=2-methylpropyl) hydrochloride. This sequence can be monitored by HPLC: column A, (1 mL/minute, 55:45 0.01M K 2 HPO 4 in H 2 O:CH 3 CN, 240 nm) R t : sulfonic acid, 2.37 minutes; (13), 6.34 minutes; (12), 8.54 minutes; tricycle byproduct, 10.17 minutes. [α] 589 25 =+49 (c 0.50, MeOH). m.p. 222° C. (dec). IR (KBr): 3350 w (NH), 2950 s, 2800-2300 w (NH 2 + ), 1620 w, 1590 w, 1540 m, 1466 w, 1420 w, 1400 w, 1350 s (SO 2 ), 1340 s (SO 2 ), 1300 s (SO.sub. 2), 1160 s (SO 2 ), 1145 s (SO 2 ), 1050 m, 1020 m, 910 w, 880 m, 740 m, 700 w. 1 H NMR (DMSO-d 6 ): δ9.82 (br s, C 4 NH 2 + ), 8.20 (s, SO 2 NH 2 ), 8.16 (s, C 3 H), 4.80 (br s, C 4 H), 3.94 (m, C 6 H 2 ), 3.83 (s, H 2 O), 2.82 (m, C 5 H 2 , C 1' H 2 ), 2.15 (septet, J=6.6, C 2' H), 0.98 (d, J=6.6, CH 3 ), 0.96 (d, J=6.6, CH 3 ). 13 C NMR (DMSO-d 6 ): δ149.4 (C 2 ), 141.8 (C 7a ), 137.5 (C 3a ), 129.8 (C 3 ), 51.2 (C 6 ), 50.9 (C 4 ), 48.3 (C 1' ), 25.5 (C 2' ), 23.7 (C 5 ), 20.3, 20.0 (2×CH 3 ). HRMS (free base, EI, 90 eV) Calcd for C 11 H 18 N 2 O 4 S 2 : 338.0429. Found: 338.0430.
Anal. Calcd for C 11 H 19 ClN 2 O 4 S 3 0.5 H 2 O: C, 34.41; H, 5.25; N, 7.30; S, 25.05; Cl, 9.23. Found: C, 34.55; H, 5.20; N, 7.21; S, 24.89; Cl, 9.50.
Employing procedures substantially as described in Example 34 Step E but substituting for the ketone 9 sub strate and the oxazaborolidine used therein, the ketone and oxazaborolidine described in Table IV, there were produced the corresponding secondary alcohols in the enantiometric ratios shown therein.
TABLE IV__________________________________________________________________________ ##STR18## ##STR19##R Ar 9 14 15 16 17__________________________________________________________________________CH.sub.3 C.sub.6 H.sub.5 98:2 99:1 82:18 98:2 97:3CH.sub.3 4-FC.sub.6 H.sub.4 97:3 84:16 85:15 97:3 94:6CH.sub.3 4-ClC.sub.6 H.sub.4 97:3 90:10 82:18 96:4 94:6CH.sub.3 4-CH.sub.3C.sub.6 H.sub.4 96:4 86:14 83:17 95:5 95:5CH.sub.3 4-CF.sub.3C.sub.6 H.sub.4 98:2 95:5 88:12 96:4 96:4CH.sub.3 4-t-BuC.sub.6 H.sub.4 95:5 93:7 84:16 98:2 91:9CH.sub.3 4-CH.sub.3 OC.sub.6 H.sub.4 97:3 95:5 84:16 95:5 97:3CH.sub.3 3-ClC.sub.6 H.sub.4 96:4 93:7 86:14 96:4 98:2CH.sub.3 3,5-Cl.sub.2C.sub.6 H.sub.3 96:4 90:10 80:20 92:8 95:5CH.sub.3 3,5-(CH.sub.3).sub.2C.sub.6 H.sub.3 96:4 97:3 86:14 96:4 97:3CH.sub.3 2-naphthyl 96:4 89:11 82:18 96:4 96:4n-C.sub.4 H.sub.9 C.sub.6 H.sub.5 93:7 96:4 88:12 95:5 98:2C.sub.6 H.sub.5 C.sub.6 H.sub.5 98:2 86:14 77:23 91:9 97:34-FC.sub.6 H.sub.4 C.sub.6 H.sub.5 99:1 94:6 76:24 88:12 97:34-ClC.sub.6 H.sub.4 C.sub.6 H.sub.5 98:2 87:13 72:38 86:14 94:64-CH.sub.3C.sub.6 H.sub.4 C.sub.6 H.sub.5 99:1 94:6 81:19 92:8 97:34-CH.sub.3 OC.sub.6 H.sub.4 C.sub.6 H.sub.5 97:3 85:15 76:24 92:8 95:5__________________________________________________________________________
EXAMPLE 35
Preparation of (R)-(+)-5,6-Dihydro-4H-thieno[2,3-b]-thiopyran-4-ol-7,7-dioxide (10)
To a magnetically stirred solution of 5,6-Dihydro-4H-thieno[2,3-b]-thiopyran-4-one-7,7-dioxide (9) (1.00 g, 4.94 mmol) in dry THF (14 mL) was added (S)-diphenylprolinol--borane complex from Example 12 (132 mg, 0.494 mmol). The solution was cooled to -15° C. and a solution of borane-methyl sulfide (10M, 0.4 mL, 4.0 mmol) in dry THF (6.8 mL) was added at a rate to maintain the internal temperature at -15° C. The solution was stirred at -15° C. for 1 hour then at 22° C. for 6 hours. The product was isolated by the method decribed in Example 34 Step E. The enantiomeric ratio of the purified product was 95.5.
EXAMPLE 36
Preparation of (R)-(+)-5,6-Dihydro-4H-thieno[2,3-b]-thiopyran-4-ol-7,7-dioxide (10)
To a magnetically stirred solution of 5,6-Dihydro-4H-thieno[2,3-b]-thiopyran-4-one-7,7-dioxide (9) (1.00 g, 4.94 mmol) in dry THF (14 mL) was added (S)-Tetrahydro-1-methyl-3,3-diphenyl-1H, 3H-pyrrolo[1,2-c][1,3,2]oxazaborole--borane complex from Example 33 (144 mg, 0.494 mmol). The solution was cooled to -15° C. and a solution of borane-methyl sulfide (10M, 0.4 mL, 4.0 mmol) in dry THF (6.8 mL) was added at a rate to maintain the internal temperature at -15° C. The solution was stirred at -15° C. for 1 hour. The product was isolated by the method decribed in Example 34 Step E. The enantiomeric ratio of the purified product was 99:1. | The chiral catalyst of general structure 1, or its enantiomer ##STR1## is prepared by treating the corresponding N-carboxy anhydride of structure 2 ##STR2## with an aryl metal, especially a phenyl metal such as an aryl magnesium halide, aryl lithium, aryl zinc or aryl cesium, to form a 1,1-diaryl-methanol of structure 3 ##STR3## followed by treatment with a compound of structure, 4 ##STR4## The catalyst, wherein R is aromatic, is novel and in some cases superior to the catalyst wherein R is alkyl or aralkyl in directing the chirality of borane-dimethyl sulfide reductions of ketones to secondary alcohols. | 2 |
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/910,846 filed Apr. 10, 2007.
FIELD OF THE INVENTION
[0002] The present invention relates in general to wellbore or borehole operations and more particularly to a methods and systems for creating seals in a wellbore utilizing a tool element that emits sealing material to form a seal between the tubing and the wellbore.
BACKGROUND
[0003] As more oilfields become mature, the need for side tracking existing wells and through tubing completions to improve production from these aging wells increases. Through tubing expandables and slotted liners may be used for side tracking and through tubing completions. Typically, at some point in the well's life, it is desired to segment or compartmentalize the well for selective treatment of a zone or to prevent encroachment of an undesired fluid. Unfortunately, through tubing expandables and slotted liners make it difficult to segment or compartmentalize the wellbore. Conventional packers do not allow segmenting or compartmentalizing these wellbores without considerable expense.
[0004] Therefore, it is a desire to provide a system and method for providing a seal behind a wellbore liner.
SUMMARY OF THE INVENTION
[0005] Apparatus and methods of forming a barrier to fluid flow behind a wellbore liner are provided. In an embodiment of the invention, a method includes the steps of conveying a tool to a position within a wellbore having a liner, the tool carrying a seal material, and injecting the seal material from the tool through the liner to form a barrier to fluid flow behind the liner.
[0006] In an embodiment of the invention, an apparatus includes a housing having a chamber carrying a seal material, and a means for injecting the seal material through the wellbore liner. The seal material may react to the hydrocarbons present in the wellbore to form the barrier. The seal material may be thixotropic in nature and/or a swellable material to facilitate placement through the liner while forming a suitable sealing plug where desired.
[0007] The foregoing has outlined the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The foregoing and other features and aspects of the present invention will be best understood with reference to the following detailed description of a specific embodiment of the invention, when read in conjunction with the accompanying drawings, wherein:
[0009] FIG. 1 is a schematic side view of an embodiment of the sealing method of the present invention; and
[0010] FIG. 2 is a further view of the sealing method illustrated in FIG. 1 .
DETAILED DESCRIPTION
[0011] Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
[0012] As used herein, the terms “up” and “down”; “upper” and “lower”; and other like terms indicating relative positions to a given point or element are utilized to more clearly describe some elements of the embodiments of the invention. Commonly, these terms relate to a reference point as the surface from which drilling operations are initiated as being the top point and the total depth of the well being the lowest point.
[0013] FIG. 1 is a schematic side view of an embodiment of the sealing method of the present invention, generally denoted by the numeral 10 . A portion of a wellbore 12 is completed with a liner 14 . Liner 14 may include one or more openings or perforations 16 along its length. For clarity, liner 14 is depicted in FIGS. 1 and 2 with multiple openings 16 . As used herein, liner 14 includes any tubing, liner or screen that has openings 16 . Openings 16 may be formed therethrough prior to hanging the tubular in the wellbore 12 or in the wellbore with punches, explosive charges, mills, drills and the like. Liner 14 may be cemented or non-cemented. Examples of liners 14 include slotted, perforated, or predrilled liners, or a screen or a pre-packed screen. An annulus 18 is formed between liner 14 and the wall 20 of wellbore 12 .
[0014] It is desired to seal annulus 18 in a region 22 . In the first step of sealing method 10 , a tool 24 is positioned within liner 14 proximate region 22 via conveyance 42 . Tool 24 includes, but is not limited to, a housing 26 having a chamber 28 carrying a seal material 30 , injection mechanism 32 , and one or more ports 34 connected to chamber 28 . Tool 24 may also include locating sub 38 and sealing members 40 . Tool 24 may also include perforating guns, drilling mechanisms or cutting mechanisms suitable for creating an opening 16 . Conveyance 42 may be an electric line, coiled tubing (CT), jointed tubing, a wireline or a slickline. Injection mechanism 32 includes piston 44 in communication with chamber 28 . Injection mechanism 32 includes pressurized fluid 46 to hydraulically actuate or motivate piston 44 against chamber 28 to expel seal material 30 from chamber 28 . Sealing members 40 are positioned about the ports 34 and are actuatable or hydraulically expandable to a position engaging liner 14 .
[0015] Tool 24 may be constructed for multiple tubing sizes. Before tool 24 is positioned proximate region 22 , tool 24 may need to be run through tubing 50 having bore 56 until it reaches region 52 , which has a bore 58 greater than bore 56 , where liner 14 is deployed. As tool 24 passes through tubing 50 , sealing members 40 may actuate or hydraulically expand to engage liner 14 to help position tool 24 into this larger bore region 52 .
[0016] In the second step of method 10 , tool 24 is positioned proximate opening 16 , or, if necessary, forms an opening 16 in liner 14 using conventional means. In the third step of method 10 , sealing members 40 may actuate to a position engaging liner 14 to form a channel 54 between housing 26 and liner 14 for injecting the seal material 30 behind liner 14 .
[0017] Referring now to FIG. 2 , in the fourth step of method 10 , a signal is sent to injection mechanism 32 to actuate the injection mechanism. The signal may be an internal signal within tool 24 , a mud pulse, a wireless or wired transmission or the like. In the fifth step of method 10 , injection mechanism 32 is actuated, and pressurized fluid 46 moves piston 44 through chamber 28 to eject seal material 30 from chamber 28 . Tool 24 then expels seal material 30 via ports 34 through channel 54 to inject seal material 30 through liner 14 , as indicated by the arrows. In the sixth step of method 10 , seal material 30 reacts with hydrocarbons in annulus 18 and forms sealing plug 48 behind liner 14 within region 22 . Sealing plug 48 may be formed circumferentially about liner 14 .
[0018] To form sealing plug 48 , seal material 30 must be suitable for injecting through aperture 16 and for setting into a sealing plug 48 in reaction with contact with hydrocarbons. Thus, it is desired that seal material 30 be thixotropic in nature so that it will set and become substantially “self-supporting” relatively quickly. It may further be desired for seal material 30 to be a swellable material, so as to seal openings 16 in region 22 . The swellable property further facilitates sealing between wellbore 12 and liner 14 . It may further be desired for seal material 30 to have a sufficiently high gel strength so as to remain where placed, yet allow for a degree of gravity-induced flow to the lower portion of region 22 , for example in horizontal wellbores. It is noted that seal material 30 may include one or more of the desired properties. It is further noted, and will be recognized with the above description of the method, that sealing plug 48 may be formed in stages or by one or more seal materials 30 . For example, a first seal material 30 being primarily thixotropic in nature may be injected through opening 16 into region 22 and then followed with a second swellable seal material 30 . It may also be desired to inject spacing fluids, such as water or drilling fluid, after one or more seal material injections.
[0019] Examples of suitable seal material 30 include, without limitation, foamed cements; unfoamed cements containing smectic clays such as bentonite and attapulgite, unfoamed cements containing welan gum, aluminum and/or iron sulphate, and/or calcium sulfate as thixotropy agents, thermosetting polymers such as epoxy, vinylester, phenolic and polyester resins, and cross-linking polymer gels (possibly with an added thixotrope).
[0020] Swellable seal material 30 swells from an unexpanded state to an expanded state when it comes into contact with or absorbs hydrocarbons. The hydrocarbons may be present naturally in wellbore 12 , or present in the formation surrounding wellbore 12 and produced into the wellbore.
[0021] Examples of suitable swellable seal material 30 and their corresponding triggering fluids (listed in parenthetical) include, without limitation: liquid hydrogel (hydrocarbon); Bacel® hardfoam (hydrocarbon); ethylene-propylene-copolymer rubber (hydrocarbon oil); ethylene-propylene-diene terpolymer rubber (hydrocarbon oil); butyl rubber (hydrocarbon oil); haloginated butyl rubber (hydrocarbon oil); brominated butyl rubber (hydrocarbon oil); chlorinated butyl rubber (hydrocarbon oil); chlorinated polyethylene (hydrocarbon oil); styrene butadiene (hydrocarbon); ethylene propylene monomer rubber (hydrocarbon); natural rubber (hydrocarbon); ethylene propylene diene monomer rubber (hydrocarbon); ethylene vinyl acetate rubber (hydrocarbon); hydrogenised acrylonitrile-butadiene rubber (hydrocarbon); acrylonitrile butadiene rubber (hydrocarbon); isoprene rubber (hydrocarbon); chloroprene rubber (hydrocarbon); and polynorbornene (hydrocarbon).
[0022] In the embodiment illustrated in FIGS. 1 and 2 , tool 24 carries both seal material 30 and injection mechanism 32 to facilitate a single trip into the well to create sealing plug 48 behind liner 14 . By providing both seal material 30 and injection mechanism 32 within tool 24 , method 10 allows for the creation of sealing plug 48 without the need for separate surface devices to pump or deliver seal material 30 downhole to region 22 . Tool 24 may further include aids, such as a source of heat or radiation, to facilitate or aid the setting of sealing plug 48 . The viscosity of seal material 30 may be varied based on the desired isolation length.
[0023] From the foregoing detailed description of specific embodiments of the invention, it should be apparent that a system and method for downhole packing that is novel has been disclosed. Although specific embodiments of the invention have been disclosed herein in some detail, this has been done solely for the purposes of describing various features and aspects of the invention, and is not intended to be limiting with respect to the scope of the invention. It is contemplated that various substitutions, alterations, and/or modifications, including but not limited to those implementation variations which may have been suggested herein, may be made to the disclosed embodiments without departing from the spirit and scope of the invention as defined by the appended claims which follow. | An apparatus and method of forming a barrier to fluid flow behind a liner are provided. In one embodiment of the invention, a method includes the steps of conveying a tool to a position within a wellbore having a liner, the tool carrying a seal material, and injecting the seal material from the tool through the liner to form a barrier to fluid flow behind the liner. In another embodiment of the invention, the apparatus includes a housing having a chamber carrying a seal material, and a means for injecting the seal material through the wellbore liner. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of International application No. PCT/FR2007/001545, filed Sep. 21, 2007, which is incorporated herein by reference in its entirety; which claims the benefit of priority of French Patent Application No. 0608348, filed Sep. 22, 2006.
[0002] A subject-matter of the present invention is pyrrolizine, indolizine and quinolizine derivatives, their preparation and their therapeutic application.
SUMMARY OF THE INVENTION
[0003] The compounds of the invention correspond to the general formula (I)
[0000]
[0000] in which:
m and n each represent, independently of one another, the number 1 or 2,
Ar represents a group chosen from the phenyl, naphth-1-yl, naphth-2-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, furan-2-yl, furan-3-yl, thien-2-yl, thien-3-yl, thiazol-2-yl and oxazol-2-yl groups, it being possible for this group Ar optionally to be substituted by one or more substituents chosen from halogen atoms and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 3 -C 7 )cycloalkyloxy, (C 3 -C 7 )cyclo-alkyl(C 1 -C 6 )alkyloxy, (C 1 -C 6 )alkylthio, (C 3 -C 7 )cycloalkylthio, (C 3 -C 7 )cycloalkyl-(C 1 -C 6 )alkylthio, mono- or polyfluoro(C 1 -C 6 )alkyl and mono- or polyfluoro(C 1 -C 6 )alkyloxy groups,
R represents either a hydrogen atom or one or more substituents, identical to or different from one another, chosen from halogen atoms and mono- or polyfluoro(C 1 -C 6 )alkyl and mono- or polyfluoro(C 1 -C 6 )alkyloxy, linear (C 1 -C 6 )alkyl, branched or cyclic (C 3 -C 7 )alkyl, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 3 -C 7 )cycloalkyloxy, (C 3 -C 7 )cycloalkyl (C 1 -C 6 )alkyloxy, (C 1 -C 6 )alkylthio, cyano, amino, phenyl, acetyl, benzoyl, (C 1 -C 6 )alkylsulphonyl, carboxyl, (C 1 -C 6 )alkoxycarbonyl and pentafluorosulphanyl groups.
DETAILED DESCRIPTION OF THE INVENTION
[0004] The compounds of general formula (I) have three asymmetric centers; they can exist in the form of enantiomers or of threo or erythro diastereoisomers with a cis or trans stereochemistry of the substituent of the bicycle, or as a mixture of such isomers. They can also exist in the form of free bases, of addition salts with acids and/or of solvates or of hydrates, namely in the form of combinations or associations with one or more molecules of water or with a solvent. Such hydrates and solvates also form part of the invention.
[0005] Among the compounds of the invention, a first group of compounds is composed of the compounds for which:
[0000] Ar represents a group chosen from the phenyl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, thien-2-yl and thien-3-yl groups, it being possible for this group Ar optionally to be substituted by one or more substituents chosen from halogen atoms and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 3 -C 7 )cycloalkyloxy, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyloxy, (C 1 -C 6 )alkylthio, (C 3 -C 7 )cycloalkylthio, (C 3 -C 7 )cyclo-alkyl(C 1 -C 6 )alkylthio, mono- or polyfluoro(C 1 -C 6 )alkyl and mono- or polyfluoro-(C 1 -C 6 )alkyloxy groups,
m, n and R being as defined above.
[0006] Among the compounds of the invention, a second group of compounds is composed of the compounds for which:
[0000] Ar represents a group chosen from the phenyl, pyridin-3-yl and thien-3-yl groups, it being possible for this group Ar optionally to be substituted by one or more substituents, identical to or different from one another, chosen from halogen atoms,
m, n and R being as defined above.
[0007] Among the compounds of the invention, a third group of compounds is composed of the compounds for which:
[0000] R represents either a hydrogen atom or one or more substituents, identical to or different from one another, chosen from halogen atoms and mono- or polyfluoro(C 1 -C 6 )alkyl, mono- or polyfluoro(C 1 -C 6 )alkyloxy, linear (C 1 -C 6 )alkyl and pentafluorosulphanyl groups,
m, n and Ar being as defined above.
[0008] Among the compounds of the invention, a fourth group of compounds is composed of the compounds for which:
m and n each represent, independently of one another, the number 1 or 2, Ar represents a group chosen from the phenyl, pyridin-3-yl and thien-3-yl groups, it being possible for this group Ar optionally to be substituted by one or more halogen atoms, R represents either a hydrogen atom or one or more substituents, identical to or different from one another, chosen from chlorine and the methyl, trifluoromethyl, trifluoromethoxy and pentafluorosulphanyl groups.
[0012] Among the compounds of the invention, a fifth group of compounds is composed of the following compounds:
trans-threo-2-Chloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2-Chloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2,6-Dichloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2,6-Dichloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2-Chloro-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. 2-Chloro-N—[(S)-(3S,8aR)-(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2-Methyl-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. cis-erythro-2-Methyl-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. 2-Chloro-N—[(S)-(3S,8aR)-(octahydroindolizin-3-yl)(pyridin-3-yl)methyl]-3-trifluoromethylbenzamide hydrochloride 1:1. 2-Chloro-N—[(S)-(3S,8aR)-(octahydroindolizin-3-yl)(thiophen-3-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1. cis-erythro-2-Chloro-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. 2-Chloro-N—[(S)-(3R,8aR)-(octahydroindolizin-3-yl)(thiophen-3-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1. 2-Chloro-N—[(S)-(3R,8aR)-(octahydroindolizin-3-yl)(pyridin-3-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1. trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2-Chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-5-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2,6-Dichloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2,6-Dichloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2-Methyl-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2,6-Dichloro-N-[(4-fluorophenyl)(octahydroquinolizin-4-yl)methyl]-3-trifluoromethylbenzamide hydrochloride 1:1. trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)(pyridin-3-yl)methyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2-Chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-5-trifluoromethyl-benzamide hydrochloride 1:1. trans-threo-2-Methyl-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1. trans-erythro-2-Chloro-N-[(octahydroquinolizin-4-yl)(thiophen-3-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1. trans-threo-2-Chloro-3-methyl-N-[(octahydroquinolizin-4-yl)phenylmethyl]benzamide hydrochloride 1:1. trans-threo-2-Chloro-N-[(4-fluorophenyl)(octahydroquinolizin-4-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1. trans-erythro-2-Chloro-N-[(4-fluorophenyl)(octahydroquinolizin-4-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1. trans-threo-2-Chloro-3-methoxy-N-[(octahydroquinolizin-4-yl)phenylmethyl]benzamide hydrochloride 1:1. trans-threo-N-[(Octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethoxybenzamide hydrochloride 1:1. trans-threo-N-[(Octahydroquinolizin-4-yl)phenylmethyl]-3-(pentafluorosulphanyl)-benzamide hydrochloride 1:1. 2-Chloro-N-[(hexahydropyrrolizin-3-yl)phenylmethyl]benzamide hydrochloride 1:1.
[0044] The compounds of general formula (I) can be prepared by a process illustrated by the following Scheme 1.
[0000]
[0045] A nitrile of general formula (II), in which m and n are as defined above, is reacted with a lithiated derivative of general formula (III), in which Ar is as defined above, in an ethereal solvent, such as diethyl ether or tetrahydrofuran, between −90° C. and −30° C.; an intermediate imine of general formula (IV) is obtained and is reduced to a primary amine of general formula (V) by a reducing agent, such as sodium borohydride, in a protic solvent, such as methanol, between 0° C. and ambient temperature. Amide coupling is subsequently carried out between the diamine of general formula (V) and an activated acid or an acid chloride of general formula (VI), in which Y represents an activated OH group or a chlorine atom and R is as defined above, using the methods known to a person skilled in the art, to arrive at the amide of general formula (I).
[0046] The compounds of general formula (II) with n=1 and m=2 have a cis and trans relative stereochemistry and they result respectively in the compounds of general formula (I) of cis-erythro and trans-threo stereochemistry.
[0047] The compounds of general formula (II) with n=2 and m=1 or n and m=2 have a trans relative stereochemistry and they result in the compounds of general formula (I) of trans-erythro and trans-threo stereochemistry.
[0048] Finally, the compound of general formula (II) with n and m=1 has a trans and cis relative stereochemistry and it results in the compounds of general formula (I) in the form of a mixture of isomers which can be separated by liquid chromatography.
[0049] Furthermore, the chiral compounds of general formula (I) can be obtained by separation of the racemic compounds by high performance liquid chromatography (HPLC) on a chiral column or by resolution of the racemic amine of general formula (V) by use of a chiral acid, such as tartaric acid, camphorsulphonic acid, dibenzoyltartaric acid or N-acetylleucine, by the fractional and preferential recrystallization of a diastereoisomeric salt in a solvent of alcohol type, or by enantioselective synthesis using a chiral nitrile of general formula (II).
[0050] The nitriles of general formula (II) are described in Synlett , (1995), 519-522, when n and m represent 1 with a cis and trans stereochemistry, in J.O.C, 55, (1990), 4688-4693 and J.O.C., 56, (1991), 4868-4874, when n represents 2 and m represents 1 with a trans stereochemistry, and in Org. Letters, 2, (2000), 2085-2088, when n represents 1 and m represents 2 with a trans and cis stereochemistry, and, finally, they can be prepared according to methods analogous to those described above when n and m represent 2 with a trans stereochemistry in the racemic or chiral series. The lithiated derivatives of general formula (III) are available commercially or they can be prepared according to methods known to a person skilled in the art and analogous to those described in J.O.C., 62, (1997), 5484-5496 and Tetrahedron Letters, 35, (1994), 3673-3674.
[0051] Certain acids and acid chlorides of general formula (VI) are available commercially or can be obtained according to methods analogous to those described in Patents EP-0 556 672 and U.S. Pat. No. 3,801,636 and in J. Chem. Soc ., (1927), 25 , Chem. Pharm. Bull ., (1992), 1789-1792 , Aust. J. Chem ., (1984), 1938-1950 and J. O. C ., (1980), 527.
[0052] The invention, according to another of its aspects, also has as subject-matter the compounds of general formula (V):
[0000]
[0000] in which
m and n each represent, independently of one another, the number 1 or 2,
Ar represents a group chosen from the phenyl, naphth-1-yl, naphth-2-yl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, furan-2-yl, furan-3-yl, thien-2-yl, thien-3-yl, thiazol-2-yl and oxazol-2-yl groups, it being possible for this group Ar optionally to be substituted by one or more substituents chosen from halogen atoms and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 3 -C 7 )cycloalkyloxy, (C 3 -C 7 )cyclo-alkyl(C 1 -C 6 )alkyloxy, (C 1 -C 6 )alkylthio, (C 3 -C 7 )cycloalkylthio, (C 3 -C 7 )cycloalkyl-(C 1 -C 6 )alkylthio, mono- or polyfluoro(C 1 -C 6 )alkyl and mono- or polyfluoro(C 1 -C 6 )alkyloxy groups.
[0053] These compounds are of use as intermediates in the synthesis of the compounds of formula (I).
[0054] Among the compounds of general formula (V) which are a subject-matter of the invention, a first group of compounds is composed of the compounds for which:
[0000] m and n each represent, independently of one another, the number 1 or 2,
Ar represents a group chosen from the phenyl, pyridin-2-yl, pyridin-3-yl, pyridin-4-yl, thien-2-yl and thien-3-yl groups, it being possible for this group Ar optionally to be substituted by one or more substituents chosen from halogen atoms and (C 1 -C 6 )alkyl, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, (C 3 -C 7 )cycloalkyloxy, (C 3 -C 7 )cycloalkyl(C 1 -C 6 )alkyloxy, (C 1 -C 6 )alkylthio, (C 3 -C 7 )cycloalkylthio, (C 3 -C 7 )cyclo-alkyl(C 1 -C 6 )alkylthio, mono- or polyfluoro(C 1 -C 6 )alkyl and mono- or polyfluoro-(C 1 -C 6 )alkyloxy groups.
[0055] Among the compounds of general formula (V) which are a subject-matter of the invention, a second group of compounds is composed of the compounds for which:
[0000] Ar represents a group chosen from the phenyl, pyridin-3-yl and thien-3-yl groups, it being possible for this group Ar optionally to be substituted by one or more substituents chosen from halogen atoms,
m and n being as defined above.
[0056] Among the compounds of general formula (V) which are a subject-matter of the invention, a third group of compounds is composed of the compounds for which:
m and n each represent, independently of one another, the number 1 or 2, Ar represents a group chosen from the phenyl, pyridin-3-yl and thien-3-yl groups, it being possible for this group Ar optionally to be substituted by one or more halogen atoms.
[0059] Among the compounds of general formula (V), mention may in particular be made of the following compounds:
trans-threo/erythro-1-(octahydroindolizin-5-yl)-1-phenylmethanamine; trans-threo-1-(octahydroindolizin-3-yl)-1-phenylmethanamine; cis-erythro-1-(octahydroindolizin-3-yl)-1-phenylmethanamine; trans-threo/erythro-1-(octahydro-2H-quinolizin-4-yl)-1-phenylmethanamine; trans-threo/erythro-1-(octahydro-2H-quinolizin-4-yl)-1-(4-fluorophenyl)methanamine; trans-threo-1-(octahydro-2H-quinolizin-4-yl)-1-(pyridin-3-yl)methanamine; trans-threo/cis-erythro-1-(octahydro-2H-quinolizin-4-yl)-1-(thien-3-yl)methanamine.
[0067] The examples which will follow illustrate the preparation of a few compounds of the invention. The elemental microanalyses, the IR and NMR spectra and chiral column HPLC confirm the structures and the enantiomeric purities of the compounds obtained.
[0068] The numbers shown in brackets in the titles of the examples correspond to those in the 1st column of the table given later.
Example 1
Compounds No. 1 and 2
trans-threo-2-Chloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1 and
trans-erythro-2-chloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1.
1.1 trans-threo/erythro-1-(octahydroindolizin-5-yl)-1-phenylmethanamine
[0069] 0.62 g (4 mmol) of bromobenzene in solution in 5 ml of anhydrous tetrahydrofuran is introduced, under an argon atmosphere, into a 50 ml round-bottomed flask equipped with a magnetic stirrer and then the medium is cooled to −75° C. 1.6 ml (4 mmol) of a 2.5M solution of butyllithium in tetrahydrofuran are added and the mixture is left stirring for 40 min. 0.3 g (2 mmol) of trans-octahydroindolizine-5-carbonitrile in solution of 5 ml of tetrahydrofuran is added at −75° C. and the mixture is allowed to return to ambient temperature over 3 h. Water and ethyl acetate are added and the aqueous phase is separated and extracted with ethyl acetate. The combined organic phases are dried over sodium sulphate and filtered, and the imine is concentrated under reduced pressure and taken up in a 50 ml round-bottomed flask with 10 ml of methanol. The mixture is cooled to −5° C. and 0.38 g (10 mmol) of sodium borohydride is slowly added. Stirring is continued while allowing the temperature of the mixture to return to ambient temperature over 12 h. The mixture is concentrated under reduced pressure and the residue is taken up in water and ethyl acetate. The phases are separated and the aqueous phase is extracted with ethyl acetate. After washing the combined organic phases, drying over sodium sulphate, filtering and evaporating, 0.5 g of product is obtained in the form of a yellow oil which is used as is in the following stage.
1.2. trans-threo-2-Chloro-N-[(octahydroindolizin-5-yl)phenylmethyl]-3-trifluoro-methylbenzamide hydrochloride 1:1 and trans-erythro-2-chloro-N-[(octahydro-indolizin-5-yl)phenylmethyl]-3-trifluoromethylbenzamide hydrochloride 1:1
[0070] 0.5 g (2.17 mmol) of 1-(octahydroindolizin-5-yl)-1-phenylmethanamine, 0.36 ml (2.6 mmol) of triethylamine and 0.63 g (2.6 mmol) of 2-chloro-3-trifluoromethylbenzoic acid chloride are successively introduced into 10 ml of dichloromethane in a 50 ml round-bottomed flask and the mixture is stirred at ambient temperature for 1 h.
[0071] The mixture is treated with water and extracted several times with dichloromethane. After washing the organic phases with water and then with a 1N aqueous sodium hydroxide solution, drying over magnesium sulphate, filtering and evaporating the solvent under reduced pressure, the residue is purified by chromatography on a column of silica gel, elution being carried out with a mixture of dichloromethane and methanol.
[0072] 0.06 g and 0.130 g of products corresponding to the trans-threo and trans-erythro isomers are obtained in the form of a colorless oil.
[0073] These products are subsequently converted to hydrochlorides starting from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0074] Finally, 0.039 g corresponding to the trans-threo isomer is isolated,
[0075] Melting point: 132-134° C.,
[0076] 1 H NMR (200 MHz, CDCl 3 ): 0.75-2.00 (m, 12H), 2.6-2.9 (m, 2H), 5.00 (d, 1H), 7.1-7.5 (m, 7H), 7.8 (t, 2H);
[0000] and 0.017 g corresponding to the trans-erythro isomer is isolated,
[0077] Melting point: 132-134° C.,
[0078] 1 H NMR (200 MHz, CDCl 3 ): 0.70-2.00 (m, 11H), 2.1-2.45 (m, 2H), 3.15-3.35 (m, 1H), 5.20 (s, 1H), 6.9 (s, 1H), 7.1-7.4 (m, 6H), 7.6-7.75 (m, 2H).
Example 2
Compound No. 5
trans-threo-2-Chloro-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1.1
2.1. trans-threo-1-(Octahydroindolizin-3-yl)-1-phenylmethanamine
[0079] 0.61 g (4.12 mmol) of trans-octahydroindolizine-3-carbonitrile, in solution in 25 ml of anhydrous tetrahydrofuran, is introduced, under an argon atmosphere, into a 100 ml round-bottomed flask equipped with a magnetic stirrer. The medium is cooled to −75° C., 6.22 ml (12.24 mmol) of a 2M solution of phenyllithium in dibutyl ether are added and the mixture is allowed to return, with stirring to ambient temperature over 5 h. 3 ml of methanol are added, then water and ethyl acetate are added and the aqueous phase is separated and extracted with ethyl acetate. The combined organic phases are dried over sodium sulphate and filtered, and the imine is concentrated under reduced pressure and taken up in a 50 ml round-bottomed flask with 25 ml of methanol. The mixture is cooled to −5° C. and 0.78 g (20.6 mmol) of sodium borohydride is slowly added. Stirring is continued while allowing the mixture to return to ambient temperature over 12 h. The mixture is concentrated under reduced pressure, the residue is taken up in water and ethyl acetate, the phases are separated and the aqueous phase is extracted with ethyl acetate. After washing the combined organic phases, drying over sodium sulphate, filtering and evaporating, 0.8 g of product is obtained in the form of a yellow oil which is used as is in the following stage.
2.2. trans-threo-2-Chloro-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1
[0080] 0.4 g (1.77 mmol) of trans-threo-1-(octahydroindolizin-3-yl)-1-phenylmethanamine, 0.3 ml (2.1 mmol) of triethylamine and 0.57 g (2.35 mmol) of 2-chloro-3-trifluoromethylbenzoic acid chloride are successively introduced into 15 ml of dichloromethane in a 50 ml round-bottomed flask and the mixture is stirred at ambient temperature for 12 h.
[0081] It is treated with water and extracted several times with dichloromethane. After washing the organic phases with water and then with a 1N aqueous sodium hydroxide solution, drying over magnesium sulphate, filtering and evaporating the solvent under reduced pressure, the residue is purified by chromatography on a column of silica gel, elution being carried out with a mixture of dichloromethane and methanol.
[0082] 0.35 g of product corresponding to the trans-threo isomer is obtained in the form of a colorless oil.
[0083] It is converted to the hydrochloride from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0084] Finally, 0.28 g is isolated in the form of a white solid.
[0085] Melting point: 138-139° C.,
[0086] 1 H NMR (200 MHz, CDCl 3 ): 1.0-1.9 (m, 10H), 2.9 (t, 1H), 3.05-3.25 (m, 2H), 3.5-3.6 (m, 1H), 5.20 (d, 1H), 7.3-7.5 (m, 6H), 7.8 (t, 2H).
Example 3
Compound No. 11
cis-erythro-2-Chloro-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1
3.1. cis-erythro-1-(octahydroindolizin-3-yl)-1-phenylmethanamine
[0087] According to the protocol described in Example 1.1, starting from 0.61 g (4 mmol) of cis-octahydroindolizine-3-carbonitrile, 0.9 g of product is obtained in the form of a yellow oil which is used as is in the following stage.
[0088] 1 H NMR (200 MHz, CDCl 3 ): 1.00-2.00 (m, 12H), 2.35-2.50 (m, 1H), 3.00-3.15 (m, 1H), 4.15 (d, 1H), 7.1-7.4 (m, 5H).
3.2. cis-erythro-2-Chloro-N-[(octahydroindolizin-3-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1
[0089] According to the protocol described in Example 2.2, starting from 0.47 g (2 mmol) of cis-erythro-1-(octahydroindolizin-3-yl)-1-phenylmethanamine and 0.58 g (2.4 mmol) of 2-chloro-3-trifluoromethylbenzoic acid chloride, 0.44 g is obtained in the form of a colorless oil corresponding to the cis-erythro isomer.
[0090] This product is subsequently converted to the hydrochloride from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0091] Finally, 0.28 g is isolated in the form of a white solid.
[0092] Melting point: 138-139° C.,
[0093] 1 H NMR (200 MHz, CDCl 3 ): 0.09-1.0 (m, 1H), 1.1-1.35 (m, 5H), 1.4-1.55 (m, 2H), 1.65-1.9 (m, 3H), 2.00-2.15 (m, 1H), 2.7-2.80 (m, 1H), 3.20-3.30 (m, 1H), 5.25 (t, 1H), 7.3-7.6 (m, 6H), 7.8-7.9 (m, 2H).
Example 4
Compounds No. 14 and 21
trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1 and
trans-erythro-2-chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethyl-benzamide hydrochloride 1:1.
4.1. trans-threo/erythro-1-(octahydro-2H-quinolizin-4-yl)-1-phenylmethanamine
[0094] 0.29 g (1.77 mmol) of trans-octahydroquinolizine-4-carbonitrile, in solution in 10 ml of anhydrous tetrahydrofuran, is introduced, under an argon atmosphere, into a 50 ml round-bottomed flask equipped with a magnetic stirrer. The medium is cooled to −75° C., 2 ml (4 mmol) of a 2M solution of phenyllithium in cyclohexane/ethyl ether (70/30) are added and the mixture is allowed to return to −50° C. with stirring over 3 h. 1 ml of methanol is added, then water and ethyl acetate are added at 25° C. and the aqueous phase is separated and extracted with ethyl acetate. The combined organic phases are dried over sodium sulphate and filtered, and the imine is concentrated under reduced pressure and taken up in a 50 ml round-bottomed flask with 10 ml of methanol. The mixture is cooled to −5° C. and 0.33 g (8.85 mmol) of sodium borohydride is slowly added. Stirring is continued while allowing the mixture to return to ambient temperature over 12 h. The mixture is concentrated under reduced pressure and the residue is taken up in water and ethyl acetate. The phases are separated and the aqueous phase is extracted with ethyl acetate. After washing the combined organic phases, drying over sodium sulphate, filtering and evaporating, 0.18 g of product is obtained in the form of a yellow oil which is used as is in the following stage.
4.2. trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoro-methylbenzamide hydrochloride 1:1 and trans-erythro-2-chloro-N-[(octahydroquinolizin-4-yl)phenylmethyl]-3-trifluoromethylbenzamide hydrochloride 1:1.
[0095] 0.18 g (0.74 mmol) of trans-threo/erythro-1-(octahydro-2H-quinolizin-4-yl)-1-phenylmethanamine, 0.20 g (0.89 mmol) of 2-chloro-3-trifluoromethylbenzoic acid, 0.17 g (0.9 mmol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) and 0.045 g (0.37 mmol) of dimethylaminopyridine are successively introduced into 10 ml of dichloromethane in a 50 ml round-bottomed flask and the mixture is stirred at ambient temperature for 12 h.
[0096] It is treated with water and extracted several times with dichloromethane. After washing the organic phases with water and then with a 1N aqueous sodium hydroxide solution, drying over magnesium sulphate, filtering and evaporating the solvent under reduced pressure, the residue is purified by chromatography on a column of silica gel, elution being carried out with a mixture of dichloromethane and methanol.
[0097] 0.13 g of compound corresponding to the trans-threo isomer and 0.024 g of compound corresponding to the trans-erythro isomer are obtained in the colorless oil form.
[0098] They are converted to hydrochlorides from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0099] Finally, 0.13 g is isolated in the form of a white solid formed of trans-threo isomer:
[0100] Melting point: 161-163° C.,
[0101] 1 H NMR (200 MHz, C 5 D 5 N): 1.2-2.0 (m, 10H), 2.15-2.35 (m, 2H), 3.2 (t, 1H), 3.65-3.8 (m, 1H), 3.85-4.0 (m, 2H), 6.30 (d, 1H), 7.3-7.6 (m, 6H), 7.8 (d, 2H);
[0000] and 0.014 g is isolated in the form of a white solid formed of trans-erythro isomer:
[0102] Melting point: 245-247° C.,
[0103] 1 H NMR (200 MHz, C 5 D 5 N): 1.0-2.1 (m, 12H), 2.3-2.6 (m, 2H), 3.00 (d, 1H), 4.0 (d, 1H), 6.30 (d, 1H), 7.2-7.8 (m, 7H), 8.3 (d, 1H).
Example 5
Compounds No. 26 and 27
trans-threo-2-Chloro-N-[(4-fluorophenyl)(octahydroquinolizin-4-yl)methyl]-3-trifluoromethylbenzamide hydrochloride 1:1 and
trans-erythro-2-chloro-N-[(4-fluorophenyl)(octahydroquinolizin-4-yl)methyl]-3-trifluoromethylbenzamide hydrochloride 1:1.
5.1. trans-threo/erythro-1-(octahydro-2H-quinolizin-4-yl)-1-(4-fluorophenyl)-methanamine
[0104] 1.33 g (7.61 mmol) of 1-bromo-4-fluorobenzene, in solution in 10 ml of anhydrous ethyl ether, are introduced, under an argon atmosphere, into a 50 ml round-bottomed flask equipped with a magnetic stirrer and then the medium is cooled to −75° C. 3.35 ml (8.37 mmol) of a 2.5M solution of butyllithium in hexane are subsequently added and the mixture is allowed to return to −40° C. with stirring over 90 min. 0.5 g (3 mmol) of trans-octahydroquinolizine-4-carbonitrile, in solution in 10 ml of ethyl ether, is subsequently added at −75° C. and this temperature is maintained for 90 min. The mixture is allowed to return to 0° C. and 2 ml of methanol are added, then, at 25° C., water and ethyl acetate are added and the aqueous phase is separated and extracted with ethyl acetate. The combined organic phases are dried over sodium sulphate and filtered, and the imine is concentrated under reduced pressure in order to be taken up in a 50 ml round-bottomed flask with 20 ml of methanol. The mixture is cooled to −5° C. and 0.57 g (15.2 mmol) of sodium borohydride is slowly added. Stirring is continued while allowing the mixture to return to ambient temperature over 12 h. The mixture is concentrated under reduced pressure and the residue is taken up in water and ethyl acetate. The phases are separated and the aqueous phase is extracted with ethyl acetate. After washing the combined organic phases, drying with sodium sulphate, filtering and evaporating, 0.97 g of product is obtained in the form of a yellow oil which is used as is in the following stage.
5.2. trans-threo-2-chloro-N-[(4-fluorophenyl)(octahydroquinolizin-4-yl)methyl]-3-tri-fluoromethylbenzamide hydrochloride 1:1 and trans-erythro-2-chloro-N-[(4-fluoro-phenyl)(octahydroquinolizin-4-yl)methyl]-3-trifluoromethylbenzamide hydrochloride 1:1
[0105] 0.4 g (1.52 mmol) of trans-threo/erythro-1-(octahydro-2H-quinolizin-4-yl)-1-(4-fluoro-phenyl)methanamine, 0.23 ml (1.8 mmol) of triethylamine and 0.4 g (1.67 mmol) of 2-chloro-3-trifluoromethylbenzoic acid chloride are successively introduced into 10 ml of dichloromethane in a 50 ml round-bottomed flask and the mixture is stirred at ambient temperature for 12 h.
[0106] The mixture is treated with water and extracted several times with dichloromethane. After washing the organic phases with water and then with a 1N aqueous sodium hydroxide solution, drying over magnesium sulphate, filtering and evaporating the solvent under reduced pressure, the residue is purified by chromatography on a column of silica gel, elution being carried out with a mixture of dichloromethane and methanol.
[0107] 0.11 g of compound corresponding to the trans-threo isomer and 0.15 g of compound corresponding to the trans-erythro isomer are obtained in the colorless oil form.
[0108] These products are subsequently converted to hydrochlorides from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0109] Finally, 0.082 g of trans-threo isomer is isolated in the form of a white solid:
[0110] Melting point: 176-178° C.,
[0111] 1 H NMR (200 MHz, CDCl 3 ): 1.3-2.3 (m, 12H), 2.6-2.85 (m, 1H), 3.2 (t, 1H), 3.55-3.8 (m, 2H), 5.65 (t, 1H), 7.15 (t, 2H), 7.35 (t, 2H), 7.5 (t, 1H), 7.8 (d, 1H), 8.05 (d, 1H), 8.75 (d, 1H, NH);
[0000] and 0.095 g of trans-erythro isomer is isolated in the form of a white solid:
[0112] Melting point: 188-189° C.,
[0113] 1 H NMR (200 MHz, CDCl 3 ): 1.1-2.6 (m, 12H), 2.7-3.2 (m, 3H), 3.95 (d, 1H), 5.80 (t, 1H), 7.15 (t, 2H), 7.35 (t, 2H), 7.5 (t, 1H), 7.8 (d, 1H), 7.95 (d, 1H), 9.3 (d, 1H, NH).
Example 6
Compound No. 20
trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)(pyridin-3-yl)methyl]-3-trifluoromethyl-benzamide hydrochloride 1:1
6.1. trans-threo-1-(Octahydro-2H-quinolizin-4-yl)-1-(pyridin-3-yl)methanamine
[0114] According to the protocol described in Example 5.1, starting from 0.8 g (5.32 mmol) of 3-bromopyridine and 0.35 g (2.13 mmol) of trans-octahydroquinolizine-4-carbonitrile, 0.57 g of product is obtained in the form of a brown oil which is used as is in the following stage.
6.2. trans-threo-2-Chloro-N-[(octahydroquinolizin-4-yl)(pyridin-3-yl)methyl]-3-tri-fluoromethylbenzamide hydrochloride 1:1
[0115] According to the protocol described in Example 5.2, starting from 0.57 g (2.32 mmol) of trans-threo-1-(octahydro-2H-quinolizin-4-yl)-1-(pyridin-3-yl)methanamine and 0.62 g (2.55 mmol) of 2-chloro-3-trifluoromethylbenzoic acid chloride, 0.21 g of compound corresponding to the trans-threo isomer is obtained.
[0116] This product is subsequently converted to the hydrochloride from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0117] Finally, 0.042 g of trans-threo isomer is isolated in the form of a white solid:
[0118] Melting point: 236-238° C.
[0119] 1 H NMR (200 MHz, CDCl 3 ): 1.3-2.4 (m, 12H), 2.6-2.9 (m, 1H), 3.2 (t, 1H), 3.65-3.90 (m, 2H), 5.75 (t, 1H), 7.3-7.55 (m, 2H), 7.8 (t, 2H), 8.05 (d, 1H), 8.65 (d, 1H), 8.8 (s, 1H), 9.1 (d, 1H, NH).
Example 7
Compounds No. 10 and 12
trans-threo-2-Chloro-N-[(octahydroindolizin-3-yl)(thien-3-yl)methyl]-3-trifluoromethyl-benzamide hydrochloride 1:1 and
cis-erythro-2-chloro-N-[(octahydroindolizin-3-yl)(thien-3-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1.
7.1. trans-threo/cis-erythro-1-(octahydro-2H-quinolizin-4-yl)-1-(thien-3-yl)methanamine
[0120] According to the protocol described in Example 5.1, starting from 1.1 g (6.9 mmol) of 3-bromothiophene and 0.41 g (2.76 mmol) of a trans/cis chiral mixture of octahydro-indolizine-5-carbonitrile, 0.51 g of product is obtained in the form of a brown oil which is used as is in the following stage.
7.2. trans-threo-2-Chloro-N-[(octahydroindolizin-3-yl)(thien-3-yl)methyl]-3-trifluoro-methylbenzamide hydrochloride 1:1 and cis-erythro-2-chloro-N-[(octahydroindolizin-3-yl)(thien-3-yl)methyl]-3-trifluoromethylbenzamide hydrochloride 1:1
[0121] According to the protocol described in Example 5.2, starting from 0.51 g (2.15 mmol) of trans-threo/cis-erythro-1-(octahydro-2H-quinolizin-4-yl)-1-(thien-3-yl)methanamine and 0.57 g (2.37 mmol) of 2-chloro-3-trifluoromethylbenzoic acid chloride, 0.25 g of compound corresponding to the trans-threo isomer and 0.14 g of compound corresponding to the cis-erythro isomer are obtained.
[0122] These products are subsequently converted to hydrochlorides from a 0.1N solution of hydrochloric acid in propan-2-ol.
[0123] Finally, 0.22 g of trans-threo isomer is isolated in the form of a white solid (RSS stereochemistry):
[0124] Melting point: 159-161° C.,
[0125] [α] D =−55.2° (c=1.01, MeOH),
[0126] 1 H NMR (200 MHz, CDCl 3 ): 1.1-2.2 (m, 10H), 2.85 (t, 1H), 3.0-3.2 (m, 2H), 3.55-3.70 (m, 1H), 5.4 (t, 1H), 7.1 (d, 1H), 7.2-7.35 (m, 2H), 7.5 (t, 1H), 7.8 (t, 2H);
[0000] and 0.16 g of cis-erythro isomer is isolated in the form of a white solid (RSS stereochemistry):
[0127] Melting point: 170-172° C.,
[0128] [α] D =+46.8° (c=1.02, MeOH),
[0129] 1 H NMR (200 MHz, CDCl 3 ): 1.1-1.9 (m, 10H), 2.0-2.2 (m, 2H), 2.75-2.9 (m, 1H), 3.25 (d, 1H), 5.4 (t, 1H), 7.1 (d, 1H), 7.2 (s, 1H), 7.35 (d, 1H), 7.5 (t, 1H), 7.8 (t, 2H).
[0130] The stereochemistry of the compounds is illustrated on the following page.
[0131] The chemical structures and the physical properties of a few compounds of the invention are illustrated in the following table.
[0132] In the “Ar” column, C 6 H 5 denotes a phenyl group, z-X—C 6 H 4 denotes a phenyl group substituted by X in the z position, C 5 H 4 N-3 denotes a pyridin-3-yl group and C 4 H 3 S-3 denotes a thien-3-yl group.
[0133] In the “Salt” column “-” denotes a compound in the base state and “HCl” denotes a hydrochloride.
[0134] In the “M.p. (° C.)” column, (d) denotes a melting point with decomposition.
[0135] In the “St.” column, t-t denotes a trans-threo configuration, t-e denotes a trans-erythro configuration, c-e denotes a cis-erythro configuration and rac. denotes a racemate.
[0000]
[0000]
TABLE
(I)
M.p.
No.
m
n
Ar
R
Salt
(° C.)
St.
1
1
2
C 6 H 5
2-Cl, 3-CF 3
HCl
132-134
t-t (rac.)
2
1
2
C 6 H 5
2-Cl, 3-CF 3
HCl
132-134
t-e (rac.)
3
1
2
C 6 H 5
2,6-(Cl) 2 ,
HCl
206-208
t-t (rac.)
3-CF 3
4
1
2
C 6 H 5
2,6-(Cl) 2 ,
HCl
254-256
t-e (rac.)
3-CF 3
5
2
1
C 6 H 5
2-Cl, 3-CF 3
HCl
138-139
t-t (rac.)
6
2
1
C 6 H 5
2-Cl, 3-CF 3
HCl
240 (d)
t-t (RSS)
7
2
1
C 6 H 5
2-CH 3 ,
HCl
140-141
t-t (rac.)
3-CF 3
8
2
1
C 6 H 5
2-CH 3 ,
HCl
247-248
c-e (rac.)
3-CF 3
9
2
1
C 5 H 4 N-3
2-Cl, 3-CF 3
HCl
145-147
t-t (RSS)
10
2
1
C 4 H 3 S-3
2-Cl, 3-CF 3
HCl
159-161
t-t (RSS)
11
2
1
C 6 H 5
2-Cl, 3-CF 3
HCl
138-139
c-e (rac.)
12
2
1
C 4 H 3 S-3
2-Cl, 3-CF 3
HCl
170-172
c-e (RRS)
13
2
1
C 5 H 4 N-3
2-Cl, 3-CF 3
HCl
131-133
c-e (RRS)
14
2
2
C 6 H 5
2-Cl, 3-CF 3
HCl
161-163
t-t (rac.)
15
2
2
C 6 H 5
2-Cl, 5-CF 3
HCl
142-144
t-e (rac.)
16
2
2
C 6 H 5
2,6-(Cl) 2 ,
HCl
286-288
t-t (rac.)
3-CF 3
17
2
2
C 6 H 5
2,6-(Cl) 2 ,
HCl
205(d)
t-e (rac.)
3-CF 3
18
2
2
C 6 H 5
2-CH 3 ,
HCl
166-167
t-e (rac.)
3-CF 3
19
2
2
4-F—C 6 H 4
2,6-(Cl) 2 ,
HCl
289-291
t-t (rac.)
3-CF 3
20
2
2
C 5 H 4 N-3
2-Cl, 3-CF 3
HCl
236-238
t-t (rac.)
21
2
2
C 6 H 5
2-Cl, 3-CF 3
HCl
245-247
t-e (rac.)
22
2
2
C 6 H 5
2-Cl, 5-CF 3
HCl
255-257
t-t (rac.)
23
2
2
C 6 H 5
2-CH 3 ,
HCl
141-143
t-t (rac.)
3-CF 3
24
2
2
C 4 H 3 S-3
2-Cl, 3-CF 3
HCl
157-159
t-e (rac.)
25
2
2
C 6 H 5
2-Cl, 3-CH 3
HCl
171-173
t-t (rac.)
26
2
2
4-F—C 6 H 4
2-Cl, 3-CF 3
HCl
176-178
t-t (rac.)
27
2
2
4-F—C 6 H 4
2-Cl, 3-CF 3
HCl
188-189
t-e (rac.)
28
2
2
C 6 H 5
2-CH 3 ,
HCl
224-226
t-t (rac.)
3-OCH 3
29
2
2
C 6 H 5
3-OCF 3
HCl
258-260
t-t (rac.)
30
2
2
C 6 H 5
3-SF 5
HCl
248-250
t-t (rac.)
31
1
1
C 6 H 5
2-Cl, 3-CF 3
—
MH + =
—
423
[0136] The compounds of the invention have been subjected to a series of pharmacological trials which have demonstrated their advantage as substances possessing therapeutic activities.
[0137] Study of glycine transportation in SK-N-MC cells expressing the native human transporter GlyT1.
[0138] The uptake of [ 14 C]glycine is studied in SK-N-MC cells (human neuroepithelial cells) expressing the native human transporter GlyT1 by measuring the radioactivity incorporated in the presence or absence of the test compound. The cells are cultured as a monolayer for 48 hours in plates pretreated with 0.02% fibronectin. On the day of the experiment, the culture medium is removed and the cells are washed with Krebs-HEPES (4-(2-hydroxyethyl)piperazine-1-ethanesulphonic acid) buffer at pH 7.4. After preincubation for 10 minutes at 37° C. in the presence either of buffer (control batch) or of test compound at various concentrations or of 10 mM of glycine (determination of the non-specific uptake), 10 μM of [ 14 C]glycine (specific activity 112 mCi/mmol) are subsequently added. Incubation is continued for 10 min at 37° C. and the reaction is halted by washing twice with pH 7.4 Krebs-HEPES buffer. The radioactivity incorporated by the cells is then estimated after adding 100 μl of liquid scintillant and stirring for 1 h. Counting is carried out on a Microbeta Tri-Lux™ counter. The effectiveness of the compound is determined by the IC 50 , the concentration of the compound which reduces by 50% the specific uptake of glycine, defined by the difference in radioactivity incorporated by the control batch and the batch which received the 10 mM glycine.
[0139] The compounds of the invention have, in this test, an IC 50 of the order of 0.001 to 0.20 μM.
[0000]
Compound 1
IC 50 = 0.08 μM
Compound 2
IC 50 = 0.023 μM
Compound 5
IC 50 = 0.003 μM
[0140] As shown by these results, the compounds of the invention exhibit a specific activity as inhibitors of the glycine transporters GlyT1.
[0141] The compounds according to the invention can thus be used in the preparation of medicaments, in particular of medicaments which are inhibitors of GlyT1 glycine transporters.
[0142] These results suggest that the compounds of the invention can be used for the treatment of behavioral disorders associated with dementia, psychoses, in particular schizophrenia (deficit form and productive form) and acute or chronic extrapyramidal symptoms induced by neuroleptics, for the treatment of various forms of anxiety, panic attacks, phobias, obsessive-compulsive disorders, for the treatment of various forms of depression, including is psychotic depression, for the treatment of disorders due to alcohol abuse or withdrawal, disorders of sexual behavior, eating disorders, for the treatment of migraine or in the treatment of primary generalized epilepsy, secondary generalized epilepsy, partial epilepsy with a simple or complex symptomatology, mixed forms and other epileptic syndromes, in complementing another antiepileptic treatment or in monotherapy.
[0143] This is why another subject-matter of the present invention is pharmaceutical compositions comprising an effective dose of at least one compound according to the invention, in the form of the base or a pharmaceutically acceptable salt or solvate, as a mixture, if appropriate, with suitable excipients.
[0144] The said excipients are chosen according to the pharmaceutical form and the method of administration desired.
[0145] The pharmaceutical compositions according to the invention may thus be intended for oral, sublingual, subcutaneous, intramuscular, intravenous, topical, intratracheal, intranasal, transdermal, rectal or intraocular administration.
[0146] The unit administration forms can be, for example, tablets, gelatin capsules, granules, powders, solutions or suspensions to be taken orally or to be injected, transdermal patches or suppositories. Ointments, lotions and collyria can be envisaged for topical administration.
[0147] The said unit forms are dosed to allow a daily administration of 0.01 to 20 mg of active principle per kg of body weight, according to the pharmaceutical dosage form.
[0148] To prepare tablets, a pharmaceutical vehicle, which can be composed of diluents, such as, for example, lactose, microcrystalline cellulose or starch, and formulation adjuvants, such as binders (polyvinylpyrrolidone, hydroxypropylmethylcellulose, and the like), flow agents, such as silica, or lubricants, such as magnesium stearate, stearic acid, glyceryl tribehenate or sodium stearylfumarate, is added to the micronized or unmicronized active principle. Wetting or surface-active agents, such as sodium lauryl sulphate, can also be added.
[0149] The preparation techniques can be direct tableting, dry granulation, wet granulation or hot melt.
[0150] The tablets can be bare, coated with sugar, for example with sucrose, or coated with various polymers or other appropriate materials. They can be designed to make possible rapid, delayed or sustained release of the active principle by virtue of polymer matrices or of specific polymers used in the coating.
[0151] To prepare gelatin capsules, the active principle is mixed with dry pharmaceutical vehicles (simple mixing, dry or wet granulation, or hot melt) or liquid or semisolid pharmaceutical vehicles.
[0152] The gelatin capsules can be hard or soft and coated or uncoated with a thin film, so as to have a rapid, sustained or delayed activity (for example, for an enteric form).
[0153] A composition in the form of a syrup or an elixir or for administration in the form of drops can comprise the active principle in conjunction with a sweetener, preferably a calorie-free sweetener, methylparaben or propylparaben, as antiseptic, a flavor enhancer and a colorant.
[0154] The water-dispersible powders and granules can comprise the active principle as a mixture with dispersing agents or wetting agents, or dispersing agents, such as polyvinylpyrrolidone, as well as with sweeteners and flavor-correcting agents.
[0155] Recourse is had, for rectal administration, to suppositories prepared with binders which melt at the rectal temperature, for example cocoa butter or polyethylene glycols.
[0156] Use is made, for parental administration, of aqueous suspensions, isotonic saline solutions or injectable sterile solutions comprising pharmacologically compatible dispersing agents and/or wetting agents, for example propylene glycol or butylene glycol.
[0157] The active principle can also be formulated in the form of microcapsules, optionally with one or more vehicles or additives or else with a polymer matrix or with a cyclodextrin (transdermal patches or sustained release forms).
[0158] The topical compositions according to the invention comprise a medium compatible with the skin. They can be provided in particular in the form of aqueous, alcoholic or aqueous/alcoholic solutions, of gels, of water-in-oil or oil-in-water emulsions having the appearance of a cream or of a gel, of microemulsions or of aerosols or in the form of vesicular dispersions comprising ionic and/or nonionic lipids. These pharmaceutical dosage forms are prepared according to methods conventional in the fields under consideration.
[0159] Finally, the pharmaceutical compositions according to the invention can comprise, in addition to a compound of the general formula (I), other active principles which can be of use in the treatment of the disorders and diseases indicated above. | The disclosure relates to a compound of formula (I):
wherein m, n, Ar, and R are as defined in the disclosure, to compositions containing them and to their therapeutic use. The disclosure also relates to processes for preparing these compounds and to certain intermediate compounds. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to freeze protection, fire protection and environmental control systems.
2. General Background of the Invention
Many buildings today have sprinkler systems therein for fire protection. These sprinkler systems usually comprise a piping system located in an air space above a drop ceiling, and a number of sprinkler nozzles extending below the drop ceiling. The drop ceiling usually has good insulating and fire-resisting values, and thermally separates this upper air space from the air space below the ceiling which, in most areas, is heated in the winter and cooled in the summer. In colder climates, where the temperature outside the building often drops below freezing during the winter, there is the danger that the water in the piping system will freeze, rendering the sprinkler system inoperable, and making the building especially vulnerable if a fire should break out while the system is frozen. In addition, frozen water pipes can be extremely disadvantageous even if no fire breaks out, because the water, which expands as it freezes, may burst the pipes. When the ice in the pipes thaws out, allowing water to escape from the broken pipes, severe water damage can occur to the building and to its contents.
Various methods have been used to attempt to keep the water in sprinkler systems, in the upper air space above drop ceilings, from freezing. One method is to insulate the piping--this may be effective if the air in the upper air space drops below freezing only briefly. However, since insulation only slows the transfer of heat, if the temperature of the upper air space should stay below freezing for any extended period of time, the water in the pipes will freeze.
Another method currently in use is to install a circulation pump in the sprinkler system. These pumps usually circulate water in the main line only, leaving branch lines unprotected against freezing.
Heaters are sometimes installed in the upper air space above the drop ceiling. In most states, however, this constitutes a violation of fire codes.
Another method of protecting sprinkler systems from freezing involves removing a number of ceiling tiles from the drop ceiling, thereby allowing the warm air below the ceiling to rise into the air space above the ceiling. Some persons do this only when a freeze is anticipated, while others remove a number of ceiling tiles when the winter begins, and do not replace them until all danger of freezing is over for the year. While both of these last-mentioned methods are effective at keeping the sprinkler system from freezing, the disadvantages of such methods far outweigh the advantages. In the case where the tiles are removed for the duration of the winter, a tremendous amount of energy is wasted, as the upper air space is heated whether the temperature outdoors is below freezing or not. In the case where the tiles are removed only when a freeze is anticipated, a sudden unpredicted drop in temperature can catch the building operator unaware, and cause the pipes to freeze. In both cases, the fire rating of the ceiling is lost, fire insurance may be voided, and, in most locations, removal of ceiling tiles is a violation of the fire code.
In view of the potential hazards which occur when sprinkler systems freeze, and the various inadequate, unsafe and/or prohibited methods mentioned above now employed to prevent sprinkler systems from freezing, it can be seen that there exists a need for a safe, economical, effective system to prevent sprinkler systems in buildings from freezing.
SUMMARY OF THE INVENTION
The present invention provides a device and system which may be used to help prevent water pipes, in air spaces above drop ceilings, from freezing in cold weather.
The device of the present invention comprises an air control unit which may be used in a drop ceiling in place of a standard ceiling tile. The air control unit includes a pivotal panel, which fits in sealing engagement on a body member, which is preferably sized to replace a standard ceiling tile in a drop ceiling. A panel-raising member is used to raise the pivotal panel to allow exchange of air between the air spaces above and below the drop ceiling. The panel-raising member is preferably attached to an electric motor which raises or lowers the pivotal panel in response to environmental conditions above or below the drop ceiling.
When used to protect water pipes in the upper air space above the drop ceiling, the motor is controlled by a temperature sensing means comprising a thermostat or a thermocouple located above the drop ceiling. The temperature sensing means causes the motor to raise the panel when the temperature of the upper air space drops dangerously close to freezing, thereby allowing warm air from beneath the ceiling to warm the space above the ceiling. When the temperature in the upper air space rises to a safe degree, the panel is lowered, preventing exchange of air between the spaces above and below the ceiling.
The device of the present invention can also be used to maintain the relative humidity of the air space below the ceiling at a comfortable level. In this instance, a humidistat located below the ceiling controls the electric motor which raises and lowers the pivotal panel. The humidistat causes the panel to raise when the relative humidity reaches an unacceptable level, allowing dry air in the upper air space to commingle with the air below the ceiling. When the relative humidity of the air below the ceiling reaches an acceptable level, the humidistat causes the panel to lower, preventing further mixing of the air on either side of the ceiling.
Whether being used to control the temperature of the air space above the ceiling, or to control the relative humidity of the air below the ceiling, the member which raises the panel comprises a fusible fire link which melts in the event of a fire, so that the panel drops to a closed position and the integrity of the fire rating of the ceiling is not compromised.
The use of the device of the present invention to help prevent water pipes, in air spaces above drop ceilings, from freezing is especially advantageous in that it provides effective freeze protection, automatically, only when necessary. It is an adequate system which is relatively economical and worry-free as compared to previously-known methods of freeze protection. Furthermore, the fusible fire link in the panel-raising member insures that the fire rating of the ceiling will be maintained in the event of a fire.
A number of the devices of the present invention can be used in a comprehensive environmental control system in a building to help prevent sprinkler systems from freezing and to maintain the relative humidity of the air below the ceiling at a comfortable level.
It is an object of the present invention to provide a device which selectively allows communication between an air space above a ceiling and an air space below the ceiling in response to environmental conditions either above or below the ceiling.
It is another object of the present invention to provide such a device which is controlled automatically by an environmental sensing means.
A further object of the present invention is to provide a device which allows air above a drop ceiling to communicate with air below a drop ceiling, while maintaining the fire rating of the ceiling in the event of a fire.
It is a further object of the present invention to provide an air control unit which is sized to replace a ceiling tile in a conventional drop ceiling.
Another object of the present invention is to provide an air control unit which responds automatically to temperature changes in the air space above a drop ceiling to allow warm air below the ceiling to mix with air above the ceiling to help insure that water pipes above the drop ceiling will not freeze in cold weather.
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature, objects and advantages of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings, in which like reference numerals denote like elements, and wherein:
FIG. 1 is a perspective, partially cut-away view of a first embodiment of the device of the present invention.
FIG. 2 is a side elevational view of the device illustrated in FIG. 1.
FIG. 3 is a detail of the device shown in FIGS. 1 and 2.
FIG. 4 is a perspective view of a second embodiment of the present invention, parts being broken away to show interior details.
FIG. 5 is a detail of the device illustrated in FIG. 4.
FIG. 6 is a schematic wiring diagram which may be used in the device shown in FIG. 4.
FIG. 7 and 8 are detail views, showing the operation of the linkage, including a fusible link incorporated with the support illustrated in the device shown in FIG. 4.
FIG. 9 is another schematic wiring diagram which may be used with the device illustrated in FIG. 4.
FIG. 10 is a perspective view of the preferred embodiment of the present invention.
FIGS. 11, 12 and 13 are detail views of various parts of the device shown in FIG. 11.
FIG. 14 is a schematic wiring diagram for use with the embodiment of the invention shown in FIG. 10.
FIG. 15 is a schematic, partial plan view showing one layout of a number of devices of the present invention installed in a conventional drop ceiling.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, a first embodiment of the present invention,air control device 1, is shown in FIGS. 1 and 2. Air control device 1 includes a base or body member 10 having an upper, generally quadrilateralplanar panel 12 pivotally connected at one end to the body by conventional means such as hinges 14. At an end of panel 12 opposite hinges 14 is a hand-manipulable member in the form of a support bar 16, which is pivotally attached to the panel 12 at 18.
Insulation 20 is provided on the walls of body 10, and an additional layer of insulation (not shown) is attached to the underside of panel 12. The insulation preferably has at least a Class 1 fire rating so as to have thesame fire rating class as most ceilings. Thus, when the panel 12 is closed,the thermal and the fire rated integrity of the ceiling in which air control device 1 is installed is assured. If desired, the insulation beneath panel 12 may be of increased thickness so as to engage the top edges of the base or body member 10 to form a near air tight seal therewith.
If desired, the bottom of body 10 may be provided with a grating 22. Grating 22 allows free passage of air into the assembly, and the grating resembles that used in the base of conventional light fixtures used in drop ceilings; thus, air control device 1 will have an aesthetic, attractive appearance from beneath.
As shown most clearly in FIG. 3, the bottom portion of the panel support bar 16 is provided with a latch 24, which is rigidly attached to support bar 16 and has a fusible link 26 incorporated therein. Latch 24 is configured to engage a support rest 28, which is mounted atop a portion ofgrating 22. Thus, in the event of a fire, fusible link 26 will melt, latch 24 will fracture and panel 12 will close by pivoting downwardly under its own weight to engage the base or body member 10.
As noted previously, the device of the present invention is intended for use in an otherwise conventional drop ceiling or the like (not shown) which includes a grid-like network of supporting rails into which conventional ceiling tiles are dropped. Such drop ceiling tiles are, ordinarily, approximately two feet by four feet in dimension. Conveniently, the body 12 is approximately the same size, so that it may simply be dropped into the support rails in place of a conventional ceiling tile. Although most ceiling tiles have dimensions as previously noted, the dimensions of body 10 can be selected to fit various other ceiling configurations.
A second, automatically operable embodiment of the present invention, air control device 2, is illustrated in FIG. 4. Air control device 2 incorporates the major features of the first embodiment, namely, a base orbody member 10, a top panel 12 and hinges 14 for pivotally interconnecting panel 12 with body 10. A transversely arranged support platform 30 is mounted in the bottom of body 10 and may be a part of or rest on top of the grating 22 illustrated in FIG. 1. A reversible electric motor 32 is mounted on transverse platform 30 and is operatively connected to a raising arm assembly 34 which is, in turn, pivotally connected to a support arm 36. Support arm 36 is pivotally mounted to platform 30 at pivot 38.
The free, distal end of support arm 36 engages panel 12 in abutting contactonly and is not in any way interconnected with panel 12. The distal end of support arm 36 includes a freely rotatable roller 40, which rides in a track 42 mounted on the underside of panel 12. Thus, for example, when themotor 32 is actuated to raise support arm 36 through raising arm assembly 34, roller 40 engages track 42 to lift the panel 12 to the position illustrated in FIG. 4. Since support arm 36 is not positively interengagedwith panel 12, the panel 12 may be manually raised and lowered independently of the operation of motor 32, raising arm assembly 34 and support arm 36.
As shown in FIGS. 4 and 5, platform 30 further includes a bracket 44 upon which are mounted a pair of microswitches 46 and 48, which control the operation of reversible motor 32 in a manner to be described below. The first microswitch 46 includes a first microswitch arm 50, and the second microswitch 48 includes a second microswitch arm 52. As shown in FIG. 4, the front wall of body 10 may include a microswitch 54 along the upper latch thereof, which may be spring-loaded when in a closed position. Switch 54 is arranged to be contacted by panel 12, when panel 12 is lowered upon body 10. Thus, when panel 12 is opened, switch 54 completes acircuit to energize a status light (not shown in FIG. 4--indicated at 56 inFIG. 6). Status light 56 provides a visual indication to any observer that panel 12 is in the open position, and may be present in device 2, or may be located in a control room of the building.
Referring now to FIGS. 7 and 8, the interrelationship of electric motor 32 and raising arm assembly 34, which operates support arm 36 and thus servesto open and close panel 12, may now be explained. The reversible electric motor includes an output motor shaft 58, to which an operating cam 60 is rigidly fixed. A link arm 62 is also rigidly attached to motor shaft 58 and a fusible fire link 64 is pivotally connected both to a free end of link arm 62 and the rear of the main portion of raising arm assembly 34, as shown in FIGS. 7 and 8. The free end of raising arm 34 is pivotally attached at 66 to support arm 36, as illustrated in FIG. 4.
When motor 32 is actuated to rotate shaft 58 counterclockwise, cam 60 and link arm 62 are also rotated counterclockwise, as shown in FIG. 8, and raising arm 34 is moved to the left, in the view shown in FIGS. 4, 7 and 8, through the pivoting interconnection of fusible fire link 64 with raising arm assembly 34 and link arm 62. With reference to FIG. 4, this causes support arm 36 to ascend. Panel 12 is thus opened, with roller 40 riding along track 42 underneath panel 12. When a predetermined degree of opening of panel 12 is reached, cam 60 strikes second microswitch arm 52 which operates microswitch 48 to interrupt current to motor 32 and thus stop its operation. Conversely, when motor 32 is actuated to close panel 12, motor shaft 58 rotates clockwise, relative to the view shown in FIGS. 7 and 8, until cam 60 strikes first microswitch arm 50 of microswitch 46. At this point, the raising arm assembly will be in the position illustrated in FIG. 7 and panel 12 will be closed against body 10. When cam 60 strikes first microswitch arm 50, electric current to motor 32 is interrupted and the motor ceases operation.
An example of wiring that might be used with air control device 2 is illustrated in FIG. 6. A standard source of 110 VAC is provided, includinga ground wire, through a terminal block 68 and an eight-pin relay 70 (relay70 is also illustrated in FIG. 4). The automatic system for raising and lowering panel 12 is controlled by an environmental sensing means 72. Environmental sensing means 72 may be a temperature sensing means such as a thermostat or a thermocouple, or it may be a humidistat. If environmental sensing means 72 is a temperature sensing means, it is located in the air space above a conventional drop ceiling, a portion of which is shown at 74 in FIG. 15. As explained above, the air space above aconventional drop ceiling 74 may have therein pipes filled with water, particularly in the event an automatic fire sprinkler system is present. It is desirable to prevent any such pipes from reaching a freezing temperature; thus, the thermostat or thermocouple 72 may be preset to activate the system when a temperature of about 32° F. (0° C.) is reached. When such a condition is sensed, thermostat or thermocouple 72 serves to close circuitry thus to activate motor 32 and move the raising arm assembly 34 to the left, as shown in FIG. 7. This causes support arm 36 to ascend, lifting and opening panel 12. With panel 12 open, warm air from below drop ceiling 74 may ascend into the air spaceabove drop ceiling 74 and warm the upper air space; thus, any pipes in the upper air space will not freeze.
It is very important that the fire rated integrity of ceiling 74 be maintained in the case of a fire. This means that, in the event of a fire,the ceiling 74 must be closed. Thus, should a fire occur with panel 12 in an open position, the fusible fire link 64 will melt, fracturing raising arm assembly 34. With the interconnection between support arm 36 and electric motor 32 thus broken, panel 12 is free to fall of its own weight against now freely-pivotal support arm 36. It will fall to a closed position against body 10, and thus the fire rated integrity of the ceiling74 is assured.
When the air space above drop ceiling 74 has warmed sufficiently, thermostat or thermocouple 72 senses the condition and causes electric motor 32 to operate to rotate motor shaft 58 in a clockwise direction, thus allowing panel 12 to close in the manner previously explained.
Environmental sensing means 72 may, instead of being a thermostat or thermocouple, be in the form of a humidistat positioned in the air space below drop ceiling 74. When a predetermined condition of relative humidityis reached, humidistat 72 operates to open panel member 12 in the manner just explained when the environmental sensing means is a thermostat or a thermocouple. With panel 12 open, air in the upper and lower air spaces oneither side of ceiling 74 commingles and the humidity in the lower air space returns to a desirable level. When this level is reached, humidistat72 operates to close panel member 12 in the manner just explained when the environmental sensing means 72 is a thermostat or thermocouple.
As explained above, panel 12 is free of any positive interengagement with support arm 36. Thus, panel 12 may be manually opened or raised independently of any operation of motor 32. This might be deemed necessaryin order to access the space above drop ceiling 74 for any reason, such as repair or maintenance of equipment located thereabove, or to allow heated air to rise into the air space above ceiling 74 when desired. To further facilitate this operation, the embodiments shown in FIGS. 1 and 4 may be combined. Thus, a second support arm such as 16 (FIG. 1) with latch 24 andsupport rest 28 might be added to the embodiment shown in FIG. 4. Preferably, the additional support bar 16 in this embodiment will have a sufficient length such that the distance between latch 24 and pivotal connection 18 is longer than the effective operating length of support arm36. In other words, the panel member 12 would be opened a sufficient distance so as to be unaffected by any unintentional or inadvertent operation of electric motor 32.
FIG. 9 illustrates another embodiment of a wiring diagram and electrical components that may be used with the embodiment of the invention illustrated in FIG. 4. With the circuitry in the condition illustrated in FIG. 9, panel 12 is in a closed position, sealed against body 10. When thehumidistat, thermocouple or thermostat 72 senses a condition in a manner previously described, the circuitry of environmental sensing means 72 is closed, which energizes relay 70, which changes the state of the relay switches from that shown in FIG. 9, and which causes electricity to flow through the on/off switch 78 through environmental sensing means 72 to microswitch 48, pins 1 and 3, wire 82, wire 84, relay pins 6 and 8, wire 86, and wire 88 to neutral.
With reference to FIG. 7 and 8, motor shaft 58 is caused to rotate in a counterclockwise direction and open panel 12, in a manner previously described. At the completion of the opening operation, cam 60 contacts arm52 of microswitch 48 to open switch 48. Switch 46 is now closed due to the separation of cam 60 from switch arm 50 of microswitch 46. Panel 12 is nowfully opened and current flows from on/off switch 78 through switch 48, status light 56 and to neutral. Status light 56 is thus lit and any observer can appreciate that panel 12 is open.
When the appropriate temperature or humidity condition is sensed by environmental sensing means 72 as previously explained, environmental sensing means 72 opens, stopping the flow of current through relay 70, which returns the relay switches to the state shown in FIG. 9. Current then flows through the on/off switch to the closed microswitch 46, relay pins 5 and 8, wire 84, wire 82, relay pin 4, wire 86, and wire 88 to neutral. This causes motor shaft 58 to rotate clockwise, in the sense of FIGS. 7 and 8, and allows panel 12 to close, as previously described. Thiscauses microswitch 48 to close, since cam 60 is released from switch arm 52. As parts return to the position illustrated in FIG. 7, and panel 12 isclosed, arm 50 of microswitch 46 is contacted by cam 60, thus opening microswitch 46. Thus, all components are returned to the condition illustrated in FIG. 9. Test switch 80 is wired in parallel with environmental sensing means 72, and overrides environmental sensing means 72 when it is desired to test the system.
The preferred embodiment of the present invention, air control device 3, isillustrated in FIG. 10. Air control device 3 is similar to air control device 2 (FIG. 4) and differs primarily in the manner in which motor 32 isinterconnected with support arm 36 and in the manner in which motor 32 is stopped. A disc 90 is rigidly fixed to shaft 58 of motor 32. One end of anarm raising assembly 91 is pivotally connected at 97 to support arm 36. Theother end of arm raising assembly 91 is pivotally connected to disc 90 at 96 (FIGS. 11-13). Arm raising assembly 91 has a fusible fire link 64 therein which melts in the event of a fire, disconnecting support arm 36 from the control of motor 32. Disk 90 has two holes, 94 and 95, therein. When either hole 94 or hole 95 lines up with switch means 89 during rotation of disc 90, operation of motor 32 is caused to stop. Switch means89 may comprise, for example, an optical switch means, such as a light emitting diode (LED) and a phototransistor, or it may comprise a spring-loaded pressure switch, and is mounted on a bracket 93.
The operation of air control device 3, like the operation of air control device 2, is controlled by an environmental sensing means 72 (not shown inFIG. 10). When the environmental sensing means 72 detects a condition in which it is necessary to raise panel 12, it causes motor 32 to rotate disc90 in a counterclockwise manner, as illustrated in FIG. 13, moving arm raising assembly 91 to the left, thereby raising support arm 36, which raises panel 12. When hole 95 lines up with switch means 89, switch means 89 causes motor 32 to stop, thereby stopping rotation of disc 90 and leaving panel 12 in a raised position, allowing air above and below the ceiling to mix. When the environmental sensing means detects a condition in which panel 12 may be lowered, it causes motor 32 to rotate disc 90 in a clockwise direction, returning disk 90 to the position shown in FIGS. 11and 12, and causing panel 12 to lower. Rotation of disc 90 ceases when hole94 lines up with switch means 89, as switch means 89 at this time causes motor 32 to stop.
As with air control device 2 shown in FIG. 4, environmental sensing means 72 may comprise a humidistat or a temperature sensing means, such as a thermostat or thermocouple, and is responsive either to the relative humidity of the air below the drop ceiling or the temperature in the air space above the drop ceiling.
FIG. 14 shows a wiring diagram which may be used with air control device 3 when motor 32 is a reversible DC motor and switch means 89 comprises a light emitting diode and a phototransistor. In this case, switch means 89 is deactivated when either of holes 94 or 95 in disc 90 is positioned suchthat the LED optically communicates with the phototransistor via hole 94 orhole 95 in disc 90. The use of low voltage DC to operate the air control device is advantageous in that, while most fire codes require AC wires in commercial buildings to be run in conduit, low voltage DC wiring can usually be run without conduit, making installation of the air control device more economical. As in the circuitry shown in FIG. 9, a test switch80 is connected in parallel with environmental sensing means 72 to allow the system to be tested when desired.
FIG. 15 diagramatically illustrates, in part, a typical installation employing the teachings of this invention. In this case, the air control devices of the present invention would be installed in the drop ceiling ofa convenience store, supermarket, or the like. Such a store might have one or more conventional open coolers as shown at 76. Such coolers are likely to raise the relative humidity in the area to an inordinate level. Accordingly, the air control devices of this invention employing an environmental sensing means in the form of a humidistat would be located, as needed, above coolers 76. One or more air control devices having sensing means in the form of a thermostat or a thermocouple could conveniently be located elsewhere in drop ceiling 74. In FIG. 15, air control devices as shown in FIGS. 4 or 10 employing humidistats are shown at A, and an air control device using a temperature sensing means is designated by "B".
It should be noted that means other than an electric motor may be used to raise and lower panel 12. Such means could be, for example, pneumatic, hydraulic, chemical, or bimetallic operations. In view of these and other changes which may be made to the embodiments disclosed herein without departing from the spirit or scope of the present invention, I hereby praythat my rights to the present inVention be limited only by the following claims. | An air control device, having a panel which opens and closes in response to changes in environmental conditions in a building, preferably is sized to replace a ceiling tile in a conventional drop ceiling. The air control device may be responsive, for example, to a change in temperature of the air space above a conventional drop ceiling, raising the panel when the temperature drops to near freezing, allowing air from below the drop ceiling to commingle with air above the drop ceiling. A support in rolling contact with the underside of the panel maintains the panel open, the support including a fusible fire link which fails or fractures in the event of a fire, thus allowing the panel to fall, insuring that the fire rating of the ceiling is not compromised. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefits of the Taiwan Patent Application Serial Number 101134666, filed on Sep. 21, 2012, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to methods for polymerizing haptens into immunogens, more particularly, to methods for polymerization of haptens into polymers having molecular weight greater than 4,000 Da, which can be used as immunogens for anti-hapten antibodies production.
[0004] 2. Description of Related Art
[0005] An immunoassay is a biochemical test often used in medical diagnoses, food inspections and environmental examinations for its benefits of high sensitivity, specificity, time-efficiency, cost-effectiveness, and easy operation. In generally, test samples as antigens are injected into animals to stimulate the immune system to generate corresponding antibodies. However, some of the test samples are too small in sizes and incapable by themselves to provoke antibody production in animals. In these cases, the test samples are considered lacking of immunogenicity, and usually known as haptens. To elicit antibody production against hapten in animals, one commonly used protocol is to conjugate hapten onto a carrier protein and with which the animals are immunized. However, this approach has its limitations, such as the needs of an appropriate carrier and a suitable chemical cross-linker, which are not always easily available. Also, to gain reproducible coupling results, well-trained laboratory personnel are required for the coupling reactions often involve intricate chemical modifications of the coupled molecules. Moreover, even the coupling chemistry is successful and the immune system of the injected animal is responsive to the hapten-carrier complex, the proportion of anti-hapten antibodies to anti-carrier antibodies in the serum may still be too small to be effective because of low hapten density of the synthesized conjugate. As a result, the purification of anti-hapten antibodies becomes difficult and costly. Therefore, it is desirable to develop an easier and more efficient alternative for the production of anti-hapten antibodies.
[0006] In the present invention, we provide methods for directly polymerizing small and non-immunogenic haptens into immunogenic antigens. This invention not only simplifies the procedures of haptenic antigen preparation but also eliminate the involvement of carriers and their concomitant problems.
SUMMARY OF THE INVENTION
[0007] The present invention provides methods of polymerizing haptens into immunogens, including the steps of: (A) providing a hapten-containing solution, wherein haptens in the hapten-containing solution are chemical compounds with two or more amine groups, chemical compounds with two or more carboxylic groups, or chemical compounds with one or more amine group and one or more carboxylic group; (B) adding a cross-linking reagent into the hapten-containing solution to polymerize the haptens to obtain an immunogen with molecular weight greater than 4,000 Da.
[0008] In the step (B) of the method of the present invention, when the haptens are the chemical compounds having two or more amine groups, the cross-linking reagent is at least one selected from the group consisting of dialdehyde, polyaldehyde, bis-carboxylic acid, and poly-carboxylic acid; when the haptens are the chemical compounds having two or more carboxylic groups, the cross-linking reagent is at least one selected from the group comprising glycol, polyol, bis-amine, and polyamine; and when the haptens are the chemical compounds having one or more amine group and one or more carboxylic group, the haptens are polymerized with the cross-linking reagent of 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide (EDC) or the amine group and the carboxylic group are cross-linked to each other through a dehydration reaction.
[0009] Further, in the step (A) of the method of the present invention, the hapten concentration used can be 1×10 −10 mM to the maximum soluble concentration of the happen, but preferably be 1×10 −10 mM to 300 mM. In the step (B), the concentration of cross-linking reagent concentration used can be 1×10 −10 mM or more, but preferably be 125 mM to 300 mM.
[0010] The reaction temperature is one important factor for the polymerization reactions. In the step (B) of the method of the present invention, the polymerization is performed at a temperature that the haptens can keep stable. Preferably, the haptens are polymerized at a temperature ranging from 4° C. to 80° C. More preferably, the haptens are polymerized at a temperature ranging from 37° C. to 80° C.
[0011] In one preferred embodiment of the present invention, the non-immunogenic melamine is polymerized into an immunogen directly, and the immunogen is injected into animals to stimulate the immune systems thereof to produce the subject antibodies. Melamine has three amine groups, and glutaraldehyde is used as the cross-linking reagent to polymerize the melamine into a macromolecular polymer. The polymerization of the melamine is shown in the following scheme I.
[0000]
[0012] Herein, a melamine concentration in the melamine-containing solution is 1×10 −10 mM to 24 mM, for which it is preferred to be 1×10 −7 mM to 20 mM; and a glutaraldehyde concentration in the melamine-containing solution is 1×10 −10 mM to 300 mM, for which it is preferred to be 1×10 −7 mM to 300 mM, and it is more preferred to be 125 mM to 250 mM. In addition, the temperature for polymerization the melamine is above 0° C., and it is preferred to be 4° C. to 80° C.
[0013] A more detailed reaction condition is described as follows. At the beginning of the reaction, 0.9 mL of a melamine solution (20 mM) is mixed with 0.1 mL of glutaraldehyde (2.5 M). After 3-day incubation at 37° C., a white precipitate can be observed. The technique of Gel Permeation Chromatography (GPC) is then used to measure the molecular size of the precipitate, wherein the observed average molecular weight thereof is 17,842 Da, the average molecular weight thereof having the lowest 10% average molecular weight is 4,067 Da, and the average molecular weight thereof having the highest 10% average molecular weight is 75,483 Da. These results indicate that haptenic melamine can be polymerized, through the aforementioned polymerization reaction, into macromolecules that can meet the general size criteria of an immunogen.
[0014] After repeatedly immunizing animals (rabbits and mice) with the polymerized melamines produced by the method of the present invention, animal sera are collected and analyzed for the presence of anti-melamine antibodies. The results of immunoassays confirm the effectiveness of the polymerized melamine in stimulating animals' immune systems. Furthermore, the results of another immunoassay, by using the same antisera, reveal the detection limit of melamine can be as low as 1.8 ppb.
[0015] Based upon the concepts and methods disclosed by the present invention, a haptenic molecule, such as peptide, protein, hormone, enzyme, drug, and toxicant comprising amine groups and/or carboxylic groups might be polymerized into macromolecule with a cross-linking reagent, and then used as an immunogen for the production of anti-hapten antibodies.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a diagram showing the analysis results of the proportion of the polymerized melamine in Embodiment 1;
[0017] FIG. 2 is a diagram showing the relationship between temperature and the polymerization reaction of melamine in Embodiments 1˜3; and
[0018] FIG. 3 is a diagram showing the results of immunoassay in Embodiment 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Embodiment 1
Polymerization Reaction
[0019] Prepared 0.9 mL of 20 mM melamine (2.52 mg in 1 mL H 2 O) in a glass vial and added to it 0.1 mL of 2.5 M glutaraldehyde, followed by incubation at 37° C. White precipitates, which are polymerization product of melamine, was observable after 3 days, and the polymerization degree of melamine reached to its plateau after 7 days ( FIG. 2 ).
[0020] <Analysis of the Proportion of Polymerized Melamine>
[0021] After polymerizing for 3 days at 37° C., 20 μL of the reaction sample was loaded onto a G-10 column and eluted with water at a flow rate of 0.4 mL/min. Fractions of 1 mL were collected and to each of them the UV absorbance at 214 nm was measured. Other than the reaction sample, 20 μL of 18 mM melamine and 20 μL of 250 mM glutaraldehyde, as controls, were also added to and eluted from the G-10 column respectively, using the same conditions as described above. The elution profiles of all three aforementioned samples are shown in FIG. 1 , and from which it is estimated that ca. 28% of melamine in the polymerization reaction sample remains as free form molecules, while the rest is in polymerized forms.
[0022] <Analysis of the Size of Polymerized Melamine>
[0023] After polymerization (37° C., 3 days), the polymerized melamine was separated with a centrifuge (10,000 g, 10 min) and the obtained precipitated was rinsed with water twice. Then, the precipitate was re-dissolved in 0.5 mL of dimethyl fumarate (DMF). The re-dissolved polymerized melamine solution was then injected into Gel Permeation Chromatography (GPC), and the analysis conditions were as follows: the chromatography column was Jordi gel DMF (polydivinylbenzene), 0.3% of lithium bromide solution in DMF was used as a mobile phase, and the flow rate of the lithium bromide solution was 1 mL/min. The analysis results indicate that the average molecular weight of the polymerized melamine is 17,842 Da, wherein the average molecular weight thereof having the lowest 10% average molecular weight is 4,067 Da, and the average molecular weight thereof having the highest 10% average molecular weight is 75,483 Da. Therefore, the molecular weight of the polymerized melamine is higher than 4,000 Da, which meets the size criteria for being an immunogen, so that the polymerized melamine obtained in the present embodiment has the potential to be used directly to stimulate anti-melamine antibodies production in animals.
Embodiments 2˜9
[0024] In the present embodiments 2˜9, melamine were polymerized under different conditions shown in table 1; wherein the term “reaction time” means the time that the precipitate can be observed.
[0000]
TABLE 1
Reaction
Melamine
Glutaraldehyde
temperature
Reaction time
Embodiment 2
18 mM
250 mM
24° C.
5-7
days
Embodiment 3
18 mM
250 mM
4° C.
19-20
days
Embodiment 4
18 mM
25 mM
37° C.
8-10
days
Embodiment 5
1.8 mM
250 mM
37° C.
7-20
days
Embodiment 6
18 mM
2.5 mM
37° C.
20
days or more
Embodiment 7
0.18 mM
250 mM
37° C.
20
days or more
Embodiment 8
0.018 mM
250 mM
37° C.
20
days or more
Embodiment 9
18 mM
250 mM
70° C.
3
hours
[0025] From the results of Embodiments 1˜3, the reaction temperature greatly influences the polymerization rate of melamine. As the reaction temperature increases, the time that the precipitate is observable becomes shorter. FIG. 2 shows the changes of absorbance at 600 nm for the reaction samples in Embodiments 1˜3. The higher polymerization degree of melamine leads to the muddier reaction solution, and the absorbance value thereof at 600 nm is also increased. Hence, the absorbance value of the reaction solution can represent the polymerization degree of melamine. From the results shown in FIG. 2 , the reaction solution containing 18 mM of melamine and 250 mM of glutaraldehyde at 37° C. (Embodiment 1) reached the maximum polymerization degree at the seventh day. If the polymerization reaction was performed at 24° C. (Embodiment 2), the maximum polymerization degree was at about the tenth day. If the polymerization reaction was performed at 4° C. (Embodiment 3), the precipitate was not observable until ca, the twentieth day. While the absorbance changes of the samples of Embodiments 4˜9 were not monitored during the course of polymerization, the appearance of white precipitates in these samples can be used as an indicator of the reaction rates. The results above reveal that temperature is a critical factor influencing the reaction rate of melamine polymerization. More specifically, the reaction rate of melamine polymerization, when using glutaraldehyde as the crosslinker, can be accelerated at a higher reaction temperature within the temperature range of the present invention.
Embodiment 10
Animal Immunization
[0026] To immunize animals (New Zealand White rabbits and Balb/c mice) with polymerized melamines, the reaction sample prepared from Embodiment 1 was used. Depending on the species of animal to be inoculated, various amounts (mouse: 0.143 mL/each inoculation; rabbit: 0.43 mL/each inoculation) of the reaction sample were added to microfuge vials respectively, washed with ddH 2 O for three times, and each of the final precipitates was re-suspended with ddH 2 O to a final volume of 0.5 mL and used as the immunogen. For the first immunization, the 0.5-mL immunogen was emulsified with 0.5 mL of complete Freund's Adjuvant and then administered intraperitoneally and subcutaneously to each mouse or intramuscularly and subcutaneously to each rabbit. Four weeks later, a second immunization was performed as the first immunization, except the incomplete Freund's Adjuvant, instead of the complete Freund's Adjuvant, was used. The final booster was given two weeks after the second immunization, using the previous conditions, but this time no adjuvant was included. Three days after the final booster, animals were bled and sera were prepared and stored at 4° C. for further analyses.
[0027] <Immunoassay of Melamine>
[0028] After series dilutions of the melamine solution, glutaraldehyde was respectively added into the melamine solutions. The final melamine concentrations in the melamine solutions were 1800 ppm, 180 ppm, 18 ppm, 1.8 ppm, 180 ppb, 18 ppb, 1.8 ppb, 0.18 ppb, and 0.018 ppb, as well as the concentration of glutaraldehyde therein was 250 mM. In addition, 250 mM of glutaraldehyde solution was prepared as a control group. After the above solutions was reacted at 70° C. for 4 hours, 10 μL of each the above solution was respectively mixed with 990 μL of double distilled water to become the melamine samples to be measured.
[0029] 50 μL of the primary antibody solution was added into the micro-centrifuge tube containing 200 μL of the melamine samples. After the mixtures were placed at room temperature for 1 hour, the precipitants contained therein were separated with a centrifuge (12000 g, 20 min), the supernatants were discarded, the precipitants were washed with water, and the above procedure was repeated twice. Subsequently, according to the different types of the primary antibodies, 50 μL of different secondary antibodies corresponding to the primary antibodies were added into each tube. For example, when the primary antibody was obtained from the mouse serum, the secondary antibody to be used was rabbit anti-mouse IgG-alkaline phosphatase (Sigma A4312). On the other hand, when the primary antibody was obtained from the rabbit serum, the secondary antibody to be used was goat anti-rabbit IgG-alkaline phosphatase (Sigma A3687). After the samples were placed at room temperature for 1 hour, the precipitants contained therein were separated with a centrifuge (12000 g 20 min), the supernatants were removed, the precipitates were washed with water, and the above procedure was repeated twice. Then, 50 μL of water was used to re-dissolve the precipitate and the samples were added into the wells of ELISA plate. 50 μL of p-Nitrophenyl phosphate (Sigma 50942) solution (0.6 mg/mL) was added into each well and reacted at room temperature for 3 hours. Finally, the absorbance value (405-490 nm) of each samples were measured by an ELISA reader, and the statistical analysis was done by student's t test (n=4, * p<0.05, ** p<0.01, *** p<0.001). As shown in FIG. 3 , the results indicate that the serum from the mouse or rabbit that was injected with the polymerized melamine of the present invention can identify melamine effectively, and the minimum detection concentration was 1.8 ppb. For the mouse or rabbit without injection of immunogen, the serum produced therefrom does not react with melamine. The aforementioned result shows that the polymerization method of the present invention can effectively polymerize haptens into an immunogen, which can effectively stimulate the immune systems of animals to produce the corresponding antibodies.
[0030] Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. | The present invention discloses methods for polymerizing non-immunogenic haptens into immunogens, which then can be used to stimulate anti-hapten antibody production in animals. Specifically, haptens with amine and/or carboxylic groups are polymerized into macromolecules by using cross-linking reagents, and the derived haptenic polymers are used to immunize animals for the production of anti-hapten antibodies. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a National Stage of International Application No. PCT/JP2010/065272, filed on Sep. 7, 2010, claiming priority based on Japanese Patent Application Nos. 2009-206953, filed Sep. 8, 2009 and JP 2010-197796, filed Sep. 3, 2010, the contents of all of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to an internal combustion engine with a supercharger comprising a turbocharger-type supercharger including a turbine portion having a plurality of exhaust gas introduction passages, and an exhaust passage including a plurality of connecting passages that connect a plurality of cylinders and a plurality of exhaust gas introduction passages, wherein exhaust gas discharged from the internal combustion engine flows through the exhaust passage.
BACKGROUND OF THE INVENTION
Exhaust-driven turbocharger-type superchargers that perform supercharging using flow strength of an exhaust stream are frequently used as superchargers to improve the intake efficiency of an internal combustion engine. For example, see Patent Document 1. Patent Document 1 discloses an exhaust system in which two or more collecting tubes joining a plurality of exhaust passages, are connected with a bridge passage serving as a communication tube. The communication tube is adapted to be opened and closed by a valve. Patent Document 1 describes the communication tube as contributing to an improvement in thermal efficiency in an internal combustion engine. Patent Document 1 also describes that the internal diameter of the communication tube may be set to 20 to 100% of the internal diameter of each collecting tube to ensure the contribution to an improvement in thermal efficiency.
Patent Document 1: Japanese Laid-open Patent Publication No. 2001-164934
SUMMARY OF THE INVENTION
However, even in the case where a turbocharger-type supercharger is driven by using flow strength of exhaust gas to improve engine power, the pressure of the exhaust gas, i.e., the exhaust pressure should be set lower than the strength against exhaust pressure in exhaust system parts such as a sealing structure of an exhaust system. To set the exhaust pressure lower than the strength against the exhaust pressure in exhaust system parts, the internal diameter of the communication tube cannot be much smaller than the internal diameter of each collecting tube. Meanwhile, when the internal diameter of the communication tube is increased, the size of the valve for opening and closing the communication tube must be increased. For this reason, it is necessary to reduce the internal diameter of the communication tube so as to miniaturize the valve for opening and closing the communication tube. However, it is impossible for the exhaust system disclosed in Patent Document 1 to achieve both a reduction in the exhaust pressure to be lower than the strength against the exhaust pressure and a reduction in the internal diameter (passage sectional area) of the communication tube (bridge passage).
It is an object of the present invention to achieve an exhaust pressure smaller than the strength against exhaust pressure, and a smaller passage sectional area of a bridge passage.
In one aspect of the invention, an internal combustion engine with a supercharger comprising: an internal combustion engine including a plurality of cylinders; an intake passage that supplies gas to the internal combustion engine; a turbocharger-type supercharger including a turbine portion having a plurality of exhaust gas introduction passages; and an exhaust passage including a plurality of connecting passages that connect the plurality of cylinders and the plurality of exhaust gas introduction passages, wherein exhaust gas discharged from the internal combustion engine flows through the exhaust passage, is provided. The internal combustion engine comprises a bridge passage that connects two or more of the plurality of connecting passages to each other; a branch passage connected to the bridge passage; and a first opening and closing device provided into the bridge passage to open and close the bridge passage.
In one embodiment, the connecting passage includes a joining passage that joins the plurality of connecting passages that connects the plurality of cylinders.
In another embodiment, the branch passage serves as an EGR passage having one end connected to the bridge passage and the other end connected to the intake passage, and the internal combustion engine further comprises: a heat exchanger provided on the EGR passage to cool exhaust gas flowing through the EGR passage; and a second opening and closing device provided downstream of the heat exchanger in the EGR passage to open and close the EGR passage.
In another embodiment, the internal combustion engine further comprises a third opening and closing device that opens and closes the EGR passage upstream of the heat exchanger.
In another embodiment, the third opening and closing device is provided on the EGR passage upstream of the heat exchanger.
In another embodiment, the first opening and closing device and the third opening and closing device configure a single switch valve that switches communication and blocking between the EGR passage and the bridge passage upstream of the heat exchanger, and that switches opening and closing of the bridge passage, the EGR passage and the bridge passage are connected via the switch valve, and the EGR passage and the bridge passage are located upstream of the heat exchanger.
In another embodiment, the internal combustion engine comprises a rate-of-revolution detection device that detects the rate of revolution of the internal combustion engine; a load detection device that detects load of the internal combustion engine; and a control device that controls opening and closing of the second opening and closing device and the first opening and closing device, wherein the control device controls opening and closing of the first opening and closing device and the second opening and closing device in accordance with the rate of revolution detected by the rate-of-revolution detection device and the load detected by the load detection device.
In a further embodiment, the internal combustion engine comprises a rate-of-revolution detection device that detects the rate of revolution of the internal combustion engine; a load detection device that detects load of the internal combustion engine; and a control device that controls opening and closing of the second opening and closing device, the first opening and closing device, and the third opening and closing device, wherein the control device controls opening and closing of the first opening and closing device, the second opening and closing device, and the third opening and closing device in accordance with the rate of revolution detected by the rate-of-revolution detection device and the load detected by the load detection device.
In another embodiment, the control device opens all of the first opening and closing device, the second opening and closing device, and the third opening and closing device in a low load region, the control device closes all of the first opening and closing device, the second opening and closing device, and the third opening and closing device in a low-revolution-rate high-load region with a load higher than that of the low load region and with low revolution rate, the control device opens the first opening and closing device and closes the second opening and closing device and the third opening and closing device in an intermediate-revolution-rate high-load region with a load higher than that of the low load region and with a higher rate of revolution than that of the low-revolution-rate high-load region, and the control device opens the first opening and closing device and the third opening and closing device and closes the second opening and closing device in a high-revolution high-load region with a load higher than that of the low load region and with a higher rate of revolution than that of the intermediate-revolution-rate high-load region.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an overall structural view of an internal combustion engine illustrating a first embodiment;
FIG. 2A is a side sectional view of a turbocharger-type supercharger;
FIG. 2B is a sectional view taken along the line 2 B- 2 B of FIG. 2A ;
FIG. 3 is a region graph represented by the rate of revolution of an engine and engine load;
FIG. 4 is a flowchart illustrating an opening and closing control program;
FIG. 5A is a graph illustrating a relation between passage diameter and output torque;
FIG. 5B is a graph illustrating a relation between passage diameter and maximum value of an exhaust pulse;
FIG. 6A is a graph illustrating a relation between passage diameter and output torque;
FIG. 6B is a graph illustrating a relation between passage diameter and maximum value of an exhaust pulse;
FIG. 7 is a graph illustrating pressure fluctuation in a connecting passage;
FIG. 8A is a graph illustrating change in pressures within an intake passage and an EGR passage;
FIG. 8B is a graph illustrating change in fluid flow rate within the EGR passage;
FIG. 8C is a graph illustrating change in fluid flow rate within the EGR passage;
FIG. 9 is an overall structural diagram of an internal combustion engine illustrating a second embodiment;
FIG. 10 is a flowchart illustrating an opening and closing control program;
FIG. 11A is an overall structural view of an internal combustion engine illustrating a third embodiment;
FIG. 11B is a sectional view illustrating an internal structure of a three-way valve V 4 ;
FIG. 11C is a sectional view illustrating the internal structure of the three-way valve V 4 ; and
FIG. 11D is a sectional view illustrating the internal structure of the three-way valve V 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A four-cylinder diesel engine of a first embodiment of the present invention will be described with reference to FIGS. 1 to 8 .
As illustrated in FIG. 1 , a diesel engine 10 serving as an internal combustion engine includes a plurality of cylinders 11 A, 11 B, 11 C, and 11 D each of which houses a non-illustrated piston. A cylinder head 12 is connected to a cylinder block (not illustrated) that forms the cylinders 11 A, 11 B, 11 C, and 11 D. Fuel injection nozzles 13 are attached to the cylinder head 12 to correspond to the cylinders 11 A, 11 B, 11 C, and 11 D. A light oil serving as fuel is supplied to the fuel injection nozzles 13 via a fuel pump 14 and a common rail 15 . The fuel injection nozzles 13 inject the fuel into each of the cylinders 11 A, 11 B, 11 C, and 11 D.
An intake manifold 16 is connected with the cylinder head 12 . An intake passage 17 is connected with the intake manifold 16 . A compressor portion 20 of a turbocharger-type supercharger 19 is provided in the middle of the intake passage 17 . The turbocharger-type supercharger 19 is a variable nozzle type supercharger that is activated by an exhaust gas stream. Air within the intake passage 17 on the upstream side of the compressor portion 20 of the turbocharger-type supercharger 19 is drawn in and fed from the compressor portion 20 .
Exhaust passages 22 A, 22 B, 22 C, and 22 D are connected with the cylinder head 12 . The exhaust passages 22 A and 22 D are merged and connected to a joining passage 23 AD. The exhaust passages 22 B and 22 C are merged and connected to a joining passage 23 BC. The joining passage 23 AD and the joining passage 23 BC are connected to a turbine portion 21 of the turbocharger-type supercharger 19 . The exhaust passages 22 A and 22 D and the joining passage 23 AD configure a first connecting passage connected to the turbine portion 21 . The exhaust passages 22 B and 22 C and the joining passage 23 BC configure a second connecting passage connected to the turbine portion 21 . The first connecting passage and the second connecting passage configure an exhaust gas passage for guiding exhaust gas discharged from the diesel engine 10 to the turbine portion 21 .
Exhaust gas discharged from the cylinders 11 A and 11 D is directed to the joining passage 23 AD via the exhaust passages 22 A and 22 D, and exhaust gas discharged from the cylinders 11 B and 11 C is directed to the joining passage 23 BC via the exhaust passages 22 B and 22 C. The exhaust gas directed from the joining passages 23 AD and 23 BC to the turbine portion 21 is discharged to the atmosphere via an exhaust passage 24 .
FIG. 2A illustrates the internal structure of the turbocharger-type supercharger 19 . The compressor portion 20 includes a compressor housing 25 and a compressor wheel 27 which is fixedly attached to a rotor shaft 26 . The turbine portion 21 includes a turbine housing 28 and a turbine wheel 29 which is fixedly attached to the rotor shaft 26 . The compressor housing 25 and the turbine housing 28 are connected via a center housing 30 .
As illustrated in FIG. 2B , a pair of scroll passages 31 AD and 31 BC each serving as an exhaust gas introduction passage is provided in the turbine housing 28 . The exhaust gas discharged from the cylinders 11 A and 11 D to the turbine portion 21 via the joining passage 23 AD is fed into the scroll passage 31 AD and a swirling passage 32 and is directed against blades 291 of the turbine wheel 29 . The exhaust gas discharged from the cylinders 11 B and 11 C to the turbine portion 21 via the joining passage 23 BC is fed into the scroll passage 31 BC and the swirling passage 32 and is directed against the blades 291 of the turbine wheel 29 . This allows the turbine wheel 29 , the rotor shaft 26 , and the compressor wheel 27 to rotate in an integrated manner.
The compressor wheel 27 introduces the air within the intake passage 17 on the upstream side of the compressor portion 20 into a compressor passage 251 provided in the compressor housing 25 , and directs the air to the intake passage 17 downstream of the compressor portion 20 .
A plurality of nozzle vanes 33 is disposed in the middle of the swirling passage 32 . As illustrated in FIG. 2B , the nozzle vanes 33 are rotatably supported with a nozzle ring 34 . The nozzle vanes 33 may change a sectional area of a flow passage between the adjacent nozzle vanes 33 .
As illustrated in FIG. 2A , an arm 36 is fixedly attached to a spindle 35 which is rotatable with respect to the nozzle ring 34 , and a unison ring 37 is inseparably engaged with the arm 36 . A spindle 38 is rotatably supported on the center housing 30 . A drive arm 39 is fixedly attached to one end of the spindle 38 . The drive arm 39 is engaged with the unison ring 37 . Rotation of the drive arm 39 about the spindle 38 allows the unison ring 37 to be rotated.
A drive lever 40 , which is fixedly attached to the other end of the spindle 38 , is rotated about the spindle 38 by an operation of a non-illustrated actuator. When the drive lever 40 is rotated, the drive arm 39 and the unison ring 37 rotate and the arm 36 and the nozzle vanes 33 rotate. That is, a vane opening degree is changed. An increase in the vane opening degree causes a decrease in turbine rotational speed, which results in a decrease in the flow rate of the air within the intake passage 17 on the downstream side of the compressor portion 20 . A decrease in the vane opening degree causes an increase in turbine rotational speed, which results in an increase in the flow rate of the air within the intake passage 17 on the downstream side of the compressor portion 20 .
As illustrated in FIG. 1 , a bridge passage 41 is connected to the middle of the joining passage 23 AD and to the middle of the joining passage 23 BC. An electric first opening and closing valve V 1 is provided in the middle of the bridge passage 41 . The bridge passage 41 is connected with one end of an EGR passage 42 serving as a branch passage. The other end of the EGR passage 42 is connected to the intake passage 17 . When the first opening and closing valve V 1 is in a closed state, the communication between the joining passage 23 AD and the joining passage 23 BC via the bridge passage 41 is blocked. When the first opening and closing valve V 1 is in an open state, the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 . The first opening and closing valve V 1 serves as a first opening and closing device that is provided to the bridge passage 41 to open and close the bridge passage 41 .
An intercooler 46 and a throttle valve 47 are each provided in the middle of the intake passage 17 . The intercooler 46 cools the air flowing within the intake passage 17 . The throttle valve 47 regulates the flow rate of the air to be fed to the cylinders 11 A, 11 B, 11 C, and 11 D. The opening degree of the throttle valve 47 is controlled in accordance with depression of a non-illustrated accelerator pedal.
The opening degree of the throttle valve 47 is detected by a throttle opening detector 45 . A rotation angle (crank angle) of a non-illustrated crank shaft is detected by a crank angle detector 48 . Throttle opening degree detection information detected by the throttle opening detector 45 and crank angle detection information detected by the rank angle detector 48 are sent to a control computer C. The control computer C calculates and controls a fuel injection time (an injection start time and an injection end time) of the fuel injection nozzles 13 based on the throttle opening degree detection information and the crank angle detection information. The control computer C also calculates the rate of revolution N of the engine based on the crank angle detection information obtained by the crank angle detector 48 . The control computer C also calculates engine load from the fuel injection time (or the amount of fuel injection) described above, for example.
The control computer C and the crank angle detector 48 configure a rate-of-revolution detection device that detects the rate of revolution of the internal combustion engine. The control computer C, the throttle opening detector 45 , and the crank angle detector 48 configure a load detection device that detects load of the internal combustion engine.
The intake manifold 16 is provided with a pressure detector 44 . The pressure detector 44 detects pressure within the intake manifold 16 , i.e., supercharging pressure. Information regarding the supercharging pressure detected by the pressure detector 44 is provided to the control computer C.
The control computer C determines a target supercharging pressure from a preliminarily set map based on the rate of revolution of the engine, engine load, and the like. Further, the control computer C controls the vane opening degree of the turbine portion 21 of the turbocharger-type supercharger 19 so that the supercharging pressure detected by the pressure detector 44 reaches the target supercharging pressure.
A heat exchanger 43 is provided in the middle of the EGR passage 42 . An electric second opening and closing valve V 2 is provided in the middle of the EGR passage 42 on the downstream side of the heat exchanger 43 . An electric third opening and closing valve V 3 is provided in the middle of the EGR passage 42 on the upstream side of the heat exchanger 43 . When the second opening and closing valve V 2 is in the closed state, communication between the heat exchanger 43 and the intake passage 17 is blocked. When the second opening and closing valve V 2 is in the open state, the heat exchanger 43 and the intake passage 17 communicate with each other via the EGR passage 42 . When the third opening and closing valve V 3 is in the closed state, communication between the heat exchanger 43 and the bridge passage 41 is blocked. When the third opening and closing valve V 3 is in the open state, the heat exchanger 43 and the joining passage 23 AD communicate with each other via the EGR passage 42 and the bridge passage 41 .
The second opening and closing valve V 2 serves as a second opening and closing device that is provided downstream of the heat exchanger 43 in the EGR passage 42 to open and close the EGR passage 42 . The third opening and closing valve V 3 serves as a third opening and closing device that is upstream of the heat exchanger 43 to open and close the EGR passage 42 .
The control computer C controls opening and closing of the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 .
FIG. 3 is a region graph represented by the rate of revolution N of the engine and engine load F. A region G 1 is a region where it is desirable that a turbine driving force in the turbocharger-type supercharger 19 is increased when the rate of revolution N of the engine is low. A region G 2 is a region where it is desirable that the turbine driving force in the turbocharger-type supercharger 19 is increased while preventing the pressure within each of the cylinders 11 A, 11 B, 11 C, and 11 D from exceeding allowable maximum pressure. A region G 3 is a region where it is desirable that the turbine driving force in the turbocharger-type supercharger 19 is increased while preventing a peak value of an exhaust pulse from exceeding an allowable maximum value. A region G 4 is a region where it is desirable that exhaust gas is sent to the EGR passage 42 to thereby clean the exhaust gas.
The region G 4 is a low load region. The region G 1 is a low-revolution-rate high-load region with a higher load and a lower rate of revolution than those of the low-load region G 4 . The region G 2 is an intermediate-revolution-rate high-load region with a load higher than that of the low-load region G 4 and with a higher rate of revolution than that of the low-revolution-rate high-load region G 1 . The region G 3 is a high-revolution-rate high-load region with a load higher than that of the low-load region G 4 and with a higher rate of revolution than that of the intermediate-revolution-rate high-load region G 2 .
FIG. 4 is a flowchart illustrating an opening and closing control program for controlling opening and closing of the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 . Hereinafter, a control for opening and closing the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 will be described with reference to this flowchart.
The control computer C judges if a pair (N, F) of the calculated rate of revolution N of the engine and the calculated engine load F is present in the low-revolution-rate high-load region G 1 (step S 1 ). When the pair (N, F) is present in the low-revolution-rate high-load region G 1 (YES in step S 1 ), the control computer C controls all of the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 to be brought into the closed state (step S 2 ). This control enables a large turbine driving force even when the rate of revolutions N of the engine is low, while preventing the exhaust gas within the joining passages 23 AD and 23 BC from being sent to the intake passage 17 via the bridge passage 41 , the EGR passage 42 , and the heat exchanger 43 .
In step S 1 , when the pair (N, F) is not present in the low-revolution-rate high-load region G 1 , the control computer C judges if the pair (N, F) is present in the intermediate-revolution-rate high-load region G 2 (step S 3 ). When the pair (N, F) is present in the intermediate-revolution-rate high-load region G 2 (YES in step S 3 ), the control computer C controls the first opening and closing valve V 1 to be brought into the open state and controls the second opening and closing valve V 2 and the third opening and closing valve V 3 to be brought into the closed state (step S 4 ). This control allows the joining passage 23 AD and the joining passage 23 BC to communicate with each other via the bridge passage 41 , while preventing the exhaust gas within the bridge passage 41 from being directed to the intake passage 17 via the EGR passage 42 and the heat exchanger 43 . In this state, a large turbine driving force can be obtained, while preventing the pressure within each of the cylinders 11 A, 11 B, 11 C, and 11 D from exceeding the allowable maximum pressure.
In step S 3 , when the pair (N, F) is not present in the intermediate-revolution-rate high-load region G 2 , the control computer C judges if the pair (N, F) is present in the high-revolution-rate high-load region G 3 (step S 5 ). When the pair (N, F) is present in the high-revolution-rate high-load region G 3 (YES in step S 5 ), the control computer C controls the first opening and closing valve V 1 and the third opening and closing valve V 3 to be brought into the open state, and controls the second opening and closing valve V 2 to be brought into the closed state (step S 6 ). This control allows the joining passage 23 AD and the joining passage 23 BC to communicate with each other via the bridge passage 41 and allows the heat exchanger 43 to communicate with the bridge passage 41 via the EGR passage 42 , while preventing the exhaust gas within the bridge passage 41 from being sent to the intake passage 17 via the EGR passage 42 . In this state, a large turbine driving force can be obtained, while preventing the peak value of the exhaust pulse from exceeding the allowable maximum value.
In step S 5 , when the pair (N, F) is not present in the high-revolution-rate high-load region G 3 , i.e., when the pair (N, F) is present in the low-load region G 4 , the control computer C controls all of the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 to be brought into the open state (step S 7 ). This control allows the joining passage 23 AD and the joining passage 23 BC to communicate with each other via the bridge passage 41 , and allows the intake passage 17 to communicate with the bridge passage 41 via the EGR passage 42 . Accordingly, the exhaust gas within the bridge passage 41 is directed to the intake passage 17 via the EGR passage 42 , and the exhaust gas is cleaned using recirculation of the exhaust gas.
The control computer C is a control device that controls opening and closing of the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 in accordance with the rate of revolution N detected by the rate-of-revolution detection device and the load F detected by the load detection device.
A curve P 1 in the graph of FIG. 7 represents pressure fluctuation in the joining passage 23 AD when the rate of revolution N of the engine is high (for example, 3600 rpm) and when the first opening and closing valve V 1 is in the open state. The abscissa axis represents crank angle, and the ordinate axis represents pressure. A curve P 2 represents pressure fluctuation in the joining passage 23 AD when the rate of revolution N of the engine is high as described above, and when the first opening and closing valve V 1 is in the closed state. When the first opening and closing valve V 1 is in the closed state, the maximum value of the exhaust pulse is excessively large. On the other hand, when the first opening and closing valve V 1 is brought into the open state, the maximum value of the exhaust pulse can be lowered to be less than compressive strength of exhaust parts (for example, a sealing structure of the exhaust system).
Step S 4 in the flowchart is a control step of opening only the first opening and closing valve V 1 to lower the maximum value of the exhaust pulse to be less than the compressive strength. As a result, in the intermediate-revolution-rate high-load region G 2 in which the rate of revolution N of the engine is intermediate, a large turbine driving force can be obtained, while preventing the pressure within each of the cylinders 11 A, 11 B, 11 C, and 11 D from exceeding the allowable maximum pressure.
On the contrary, the low-revolution-rate high-load region G 1 is a region where the rate of revolution N of the engine is low is a region where it is desirable that the maximum value of the exhaust pulse is set to be approximate to the compressive strength of the exhaust parts (for example, sealing structure of an exhaust system) to thereby increase the turbine driving force. Step S 2 in the flowchart is a control step therefor. This enables a large turbine driving force also in the low-revolution-rate high-load region G 1 in which the rate of revolution N of the engine is low.
When the sectional area of the bridge passage 41 is small in the high-revolution-rate high-load region G 3 in which the rate of revolution N of the engine is high, there is a possibility that the maximum value of the exhaust pulse cannot be set to be less than the compressive strength with opening only the first opening and closing valve V 1 .
Each of curves T 1 , T 2 , T 3 , and T 4 in the graph illustrated in FIG. 5A represents a change in output torque when the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 and when the heat exchanger 43 communicates with the bridge passage 41 via the EGR passage 42 . The axis of abscissa represents the passage diameter of the bridge passage 41 , and the axis of ordinate represents an output torque. The curve T 1 represents a change in output torque when a vane opening degree ratio in the turbocharger-type supercharger 19 is 50%. The curve T 2 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 60%. The curve T 3 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 70%. The curve T 4 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 80%.
Each of curves E 1 , E 2 , E 3 , and E 4 in the graph illustrated in FIG. 5B represents a change in maximum value of the exhaust pulse when the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 and when the heat exchanger 43 communicates with the bridge passage 41 via the EGR passage 42 . The abscissa axis represents the passage diameter of the bridge passage 41 , and the ordinate axis represents the maximum value of the exhaust pulse. The curve E 1 represents change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 50%. The curve E 2 represents change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 60%. The curve E 3 represents a change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 70%. The curve E 4 represents a change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 80%.
FIGS. 5A and 5B each illustrate the case where the rate of revolution of the engine is high (for example, 3600 rpm). A passage diameter So represents the passage diameter of the bridge passage 41 .
In this embodiment, assuming that a minimum value of a required output torque is 300 Nm and an allowable maximum value of an exhaust pulse is 450 kPa when the vane opening degree ratio is 60%, when the passage diameter So of the bridge passage 41 is set to a necessary value, the minimum value of the output torque can be obtained and the maximum value of the exhaust pulse can be set to be equal to or lower than the allowable value.
On the other hand, each of curves t 1 , t 2 , t 3 , and t 4 in the graph illustrated in FIG. 6A represents a change in output torque when the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 , while the heat exchanger 43 does not communicate with the bridge passage 41 via the EGR passage 42 . The abscissa axis represents the passage diameter of the bridge passage 41 , and the ordinate axis represents an output torque. The curve t 1 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 50%. The curve t 2 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 60%. The curve t 3 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 70%. The curve t 4 represents a change in output torque when the vane opening degree ratio in the turbocharger-type supercharger 19 is 80%.
Each of curves e 1 , e 2 , e 3 , and e 4 in the graph illustrated in FIG. 6B represents a change in maximum value of the exhaust pulse when the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 , while the heat exchanger 43 does not communicate with the bridge passage 41 via the EGR passage 42 . The abscissa axis represents the passage diameter of the bridge passage 41 , and the ordinate axis represents the maximum value of the exhaust pulse. The curve e 1 represents a change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 50%. The curve e 2 represents a change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 60%. The curve e 3 represents a change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 70%. The curve e 4 represents a change in maximum value of the exhaust pulse when the vane opening degree ratio in the turbocharger-type supercharger 19 is 80%.
In both FIGS. 6A and 6B , the rate of revolution of the engine is high (for example, 3600 rpm). The passage diameter So represents the passage diameter of the bridge passage 41 .
In the case of FIGS. 6A and 6B , if the passage diameter So of the bridge passage 41 is set larger than when the heat exchanger 43 communicate with the bridge passage 41 via the EGR passage 42 , the minimum value of the output torque can be obtained. Furthermore, the maximum value of the exhaust pulse can be set to be equal to or lower than the allowable value.
The difference between the case of FIGS. 5A and 5B and the case of FIGS. 6A and 6B resides in whether the passage volume of the heat exchanger 43 is used or not.
Step S 6 in the flowchart is a control step of opening not only the first opening and closing valve V 1 but also the third opening and closing valve V 3 to thereby set the maximum value of the exhaust pulse to be less than the compressive strength. When the third opening and closing valve V 3 is brought into the open state, the heat exchanger 43 communicates with the bridge passage 41 via the EGR passage 42 , and the passage volume in the heat exchanger 43 is used to lower the maximum value of the exhaust pulse. As a result, even when the passage diameter of the bridge passage 41 is small, the maximum value of the exhaust pulse can be lowered and a large turbine driving force can be obtained in the high-revolution-rate high-load region G 3 .
The low-load region G 4 in which recirculation of the exhaust gas is carried out is a region where it is desirable that recirculation of the exhaust gas is carried out to clean the exhaust gas. However, there is a possibility that the air within the intake passage 17 backflows into the EGR passage 42 .
Curve Q in the graph illustrated in FIG. 8A represents pressure within the intake passage 17 on the downstream side of the intercooler 46 when the exhaust gas is sent only from the joining passage 23 AD to the EGR passage 42 and the intake passage 17 . The abscissa axis represents crank angle, and the ordinate axis represents pressure. A curve V represents a change in the pressure within the EGR passage 42 on the downstream side of the heat exchanger 43 when the exhaust gas is sent only from the joining passage 23 AD to the EGR passage 42 and the intake passage 17 . As indicated by the curve Q, the pressure within the intake passage 17 may become higher than the pressure within the EGR passage 42 on the downstream side of the heat exchanger 43 . In such a case, the air within the intake passage 17 backflows into the EGR passage 42 .
The curve U in the graph illustrated in FIG. 8B represents change in fluid flow rate (units of kg/s) of the EGR passage 42 on the downstream side of the heat exchanger 43 . The abscissa axis represents crank angle, and the ordinate axis represents fluid flow rate. The curve U represents change in fluid flow rate of the exhaust gas in the case corresponding to the curve Q illustrated in FIG. 8A (i.e., when the exhaust gas is provided only from the joining passage 23 AD to the EGR passage 42 and the intake passage 17 ). The curve U below the abscissa axis represents backflow of the air within the intake passage 17 to the EGR passage 42 .
Step S 7 in the flowchart is a control step of opening all of the first opening and closing valve V 1 , the second opening and closing valve V 2 , and the third opening and closing valve V 3 , to provide the exhaust gas from both the joining passages 23 AD and 23 BC to the EGR passage 42 and the intake passage 17 . This control prevents backflow from the intake passage 17 to the EGR passage 42 as indicated by the curve W in the graph illustrated in FIG. 8C . That is, step S 7 is a control step for preventing backflow from the intake passage 17 to the EGR passage 42 .
The first embodiment has the following effects.
(1) By closing the second opening and closing valve V 2 and opening the first opening and closing valve V 1 and the third opening and closing valve V 3 , the passage volume in the heat exchanger 43 can be used to reduce the maximum value of the exhaust pulse. As a result, even when the passage diameter of the bridge passage 41 is small, the maximum value of the exhaust pulse can be lowered and a large turbine driving force can be obtained. Accordingly, the first opening and closing valve V 1 can be downsized.
(2) When the third opening and closing valve V 3 is omitted, in the state where the second opening and closing valve V 2 is closed and the first opening and closing valve V 1 is opened, the passage volume within the heat exchanger 43 is constantly used to reduce the maximum value of the exhaust pulse. While such control is possible, the presence of the third opening and closing valve V 3 allows finer control of the turbine driving force in accordance with the rate of revolution N of the internal combustion engine and the load F, as in the case where the internal combustion engine is present in the intermediate-revolution-rate high-load region G 2 , for example.
Next, a second embodiment will be described with reference to FIGS. 9 and 10 . The same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description thereof is omitted.
In the second embodiment, the third opening and closing valve V 3 of the first embodiment is omitted. In this case, the control of opening and closing the first opening and closing valve V 1 and the second opening and closing valve V 2 is carried out as in steps S 8 , S 9 , S 10 , S 11 , and S 12 in the flowchart of FIG. 10 . The control computer C is a control device that controls opening and closing of the first opening and closing valve V 1 and the second opening and closing valve V 2 in accordance with the rate of revolution N detected by the rate-of-revolution detection device and the load F detected by the load detection device.
Even when the third opening and closing valve V 3 is omitted, the same effects as those described in the item (1) of the first embodiment can be obtained.
Next, a third embodiment will be described with reference to FIGS. 11A , 11 B, 11 C, and 11 D. The same components as those of the first embodiment are denoted by the same reference numerals, and the detailed description thereof is omitted.
As illustrated in FIG. 11A , an electric three-way valve V 4 is provided in the bridge passage 41 . The rotational position of the three-way valve V 4 is controlled by the control computer C. As illustrated in FIG. 11B , the three-way valve V 4 includes a rotation valve body 50 in a valve housing 49 , and three ports 501 , 502 , and 503 are provided in the rotation valve body 50 so as to communicate with one another. Three valve holes 491 , 492 , and 493 are provided in the valve housing 49 . The valve hole 491 communicates with the joining passage 23 AD via the bridge passage 41 , and the valve hole 492 communicates with the joining passage 23 BC via the bridge passage 41 . The valve hole 493 communicates with the EGR passage 42 .
When the pair of the rate of revolution N of the engine and the engine load F is present in the low-revolution-rate high-load region G 1 (see FIG. 3 ), the three-way valve V 4 is controlled to be brought into the state illustrated in FIG. 11D , and the second opening and closing valve V 2 is controlled to be brought into the closed state. In this state, the communication between the joining passage 23 AD and the joining passage 23 BC via the bridge passage 41 is blocked, as in step S 2 of the flowchart of FIG. 4 .
When the pair of the rate of revolution N of the engine and the engine load F is present in the intermediate-revolution-rate high-load region G 2 (see FIG. 3 ), the three-way valve V 4 is controlled to be brought into the state illustrated in FIG. 11C , and the second opening and closing valve V 2 is controlled to be brought into the closed state. In this state, the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 , while the communication between the EGR passage 42 and the bridge passage 41 is blocked, as in step S 4 of the flowchart of FIG. 4 .
When the pair of the rate of revolution N of the engine and the engine load F is present in the high-revolution-rate high-load region G 3 (see FIG. 3 ), the three-way valve V 4 is controlled to be brought into the state illustrated in FIG. 11B , and the second opening and closing valve V 2 is controlled to be brought into the closed state. In this state, the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 , and the heat exchanger 43 communicates with the bridge passage 41 via the EGR passage 42 , as in step S 6 of the flowchart of FIG. 4 .
When the pair of the rate of revolution N of the engine and the engine load F is present in the low-load region G 4 (see FIG. 3 ), the three-way valve V 4 is controlled to be brought into the state illustrated in FIG. 11B , and the second opening and closing valve V 2 is controlled to be brought into the open state. In this state, the joining passage 23 AD and the joining passage 23 BC communicate with each other via the bridge passage 41 , and the bridge passage 41 and the intake passage 17 communicate with each other via the EGR passage 42 , as in step S 7 of the flowchart of FIG. 4 .
The three-way valve V 4 is a single switch valve that switches communication and blocking between the EGR passage 42 and the bridge passage 41 on the upstream side of the heat exchanger 43 , and that switches opening and closing of the bridge passage 41 . The EGR passage 42 and the bridge passage 41 on the upstream side of the heat exchanger 43 are connected via the three-way valve V 4 . That is, the three-way valve V 4 , which is a switch valve, serves as the first opening and closing device and the third opening and closing device. Use of such a three-way valve V 4 having combined configuration contributes to simplification of the piping configuration of the exhaust gas passage.
In the present invention, the following embodiments can also be implemented.
In the first embodiment, one of the exhaust passages 22 A and 22 D configuring the first connecting passage and one of the exhaust passages 22 B and 22 C configuring the second connecting passage may be connected to each other with a bridge passage.
The present invention can be applied to a six-cylinder engine disclosed in Patent Document 1, or a V-shaped eight-cylinder engine.
For example, cylinders in the six-cylinder engine may be divided into three groups, and each connecting passage may be guided to a turbocharger-type supercharger from each group. In this case, each connecting passage is connected to the corresponding bridge passage in the middle of each connecting passage, and each bridge passage is provided with the first opening and closing device.
Two or more of a plurality of connecting passages for connecting a plurality of exhaust gas introduction passages with a plurality of cylinders in one-to-one correspondence may be connected to each other via a bridge passage.
In an internal combustion engine with no EGR passage, the exhaust passage 24 and the bridge passage 41 on the downstream side of the turbine portion 21 may be connected together via a branch passage, and the third opening and closing device may be provided on the branch passage.
The present invention can also be applied to a gasoline engine. | An internal combustion engine with a supercharger comprises an internal combustion engine including a plurality of cylinders; an intake passage that supplies gas to the internal combustion engine; a turbocharger-type supercharger including a turbine portion having a plurality of exhaust gas introduction passages; and an exhaust passage including a plurality of connecting passages that connect the plurality of cylinders and the plurality of exhaust gas introduction passages, wherein exhaust gas discharged from the internal combustion engine flows through the exhaust passage. The internal combustion engine comprises a bridge passage that connects two or more of the plurality of connecting passages to each other; a branch passage connected to the bridge passage; and a first opening and closing device provided into the bridge passage to open and close the bridge passage. | 5 |
This application is a U.S. National Stage Application of International Application No. PCT/AU2007/001396, filed 21 Sep. 2007, which claims the benefit of Australian Patent Application Nos. AU 2006905242, filed 25 Sep. 2006 and AU 2007901668, filed 30 Mar. 2007, each of which is incorporated herein by reference in its entirety.
FIELD OF INVENTION
The present invention relates to diesel engines and fuel systems for diesel engines. The present invention has particular but not exclusive application for use with trucks.
BACKGROUND OF THE INVENTION
Trucks and in particular long haul trucks use large volumes of diesel fuel in transporting goods. As the price of diesel increases, the cost of freighting goods also increases. While at least part of the increase in costs is passed on to the end consumer, market forces have caused the truck operator to absorb much of the additional costs thereby reducing their profit margin. Consequently alternative fuel sources have been investigated.
LPG (Liquid Petroleum Gas) has been used as an alternative fuel source for diesel engines. While LPG is stored under pressure (approximately 150 psi) in the tank which maintains the LPG in a liquid state, LPG is usually used in a gaseous state at pressures well below 140 psi which is the pressure required to maintain LPG in a liquid state.
LPG has also been used with diesel in dual fuel systems. In US2005205021 a separate set of injectors introduce gaseous LPG into the combustion chamber, whereas in U.S. Pat. No. 5,408,957, U.S. Pat. No. 4,520,766, JP1318755 and GB1252458, gaseous LPG is mixed with air prior to introducing the air mixture to the combustion chamber.
The problem with using LPG as the sole fuel source for diesel engines is that the engines need substantial modification to overcome the reduction in lubricity with the use of LPG and the ability to provide the combustion of the LPG. Modification of engines is a major expense and voids the warranties from the engine manufacturer. Even with LPG and diesel dual fuel systems, diesel engines need to be modified to allow the introduction of LPG into the combustion chamber.
OBJECT OF THE INVENTION
It is an object of the present invention to provide an alternative dual fuel system that overcomes at least in part the abovementioned problems.
SUMMARY OF THE INVENTION
The present invention arose from taking an alternative approach by understanding the effects of pressure on LPG and developing a different solution to dual fuel systems using pressurized LPG and without substantially modifying the diesel engine.
In one aspect the present invention broadly resides in a dual fuel system for use by an internal combustion diesel engine including
a fuel tank to store pressurized liquefied gas;
a proportioning valve means operatively connected to the fuel tank and adapted to control the flow of the liquefied gas; and
a mixing chamber operatively connected to the proportioning valve and adapted to mix a proportioned flow of the liquefied gas and a proportioned flow of diesel to form a liquid fuel mixture, wherein the liquid fuel mixture remains under pressure and is introduced into a combustion chamber of the diesel engine.
In another aspect the present invention broadly resides in a dual fuel system assembly for installation with an internal combustion diesel engine including
a fuel tank to store pressurized liquefied gas;
a proportioning valve means operatively connectable to the fuel tank and adapted to control the flow of the liquefied gas; and
a mixing chamber operatively connectable to the proportioning valve and adapted to mix a proportioned flow of the liquefied gas and a proportioned flow of diesel to form a liquid fuel mixture, wherein in use the assembly can provide the liquid fuel mixture to a combustion chamber of the diesel engine.
The proportioning valve means preferably includes a flow control valve operatively controlled by an electronic control board. The electronic control board preferably controls the flow control valve in response to processed information from the vehicle electronic control unit.
Preferably the diesel fuel is pressurized prior to entering the mixing chamber. The diesel fuel is preferably pressurized by an inline pump and the fuel is stored within a pressurized tank prior to use. Preferably the supply of pressurized diesel fuel to the mixing chamber is regulated by a flow control valve that is operatively controlled by an electronic control board. The electronic control board is preferably controlled by the vehicle electronic control unit that receives and processes information to provide a relevant signal to the electronic control board.
The liquefied gas is preferably filtered before the proportioning valve with an inline filter.
Preferably the LPG tank, proportioning valve means and mixing chamber are linked by a gas pipeline.
The pipeline between the LPG tank and proportioning valve preferably includes at least one closeable valve. In a preferred embodiment there is a one-way non-return valve and a closeable valve within the line between the LPG tank and the proportioning valve means.
The dual fuel assembly may be fitted prior to delivery of a diesel engine vehicle or fitted as an after market kit.
The liquefied gas may be LPG, propane, natural gas or compressed natural gas.
Preferably the liquefied gas tank stores LPG under pressure of about 150 psi but above its vapor pressure of 80 psi.
In a further aspect the invention broadly resides in an internal combustion diesel engine with dual fuel system including
a first tank to store pressurized liquefied gas;
a second tank to store pressurized diesel;
a first proportioning valve means operatively connected to the first tank and adapted to control the flow of the liquefied gas;
a second proportioning valve means operatively connected to the second tank and adapted to control the flow of the diesel;
a mixing chamber operatively connected to the first proportioning valve means and second proportioning valve means, said mixing chamber is adapted to mix a proportioned flow of the liquefied gas and a proportioned flow of diesel to form a liquid fuel mixture, and
distribution means for distributing the liquid fuel mixture to each internal combustion chamber, wherein an engine processor controls the proportioning of the fuels by regulating the respective proportioning valve means in accordance with demand.
The abovementioned preferred embodiments for the features of the dual fuel system and dual fuel system assembly also apply for this aspect of the invention.
The second tank preferably receives pressurized diesel via an inline filter and pump from a diesel fuel tank.
The second proportioning valve means preferably includes a flow control valve operatively controlled by an electronic control board. The electronic control board preferably controls the flow control valve in response to processed information from the vehicle electronic control unit. The vehicle electronic control unit receives and processes input regarding the demand of fuel by the engine.
Preferably there is an accelerometer means that measures the acceleration of the vehicle and whether the vehicle is traveling up or down an incline. Input from the accelerometer means preferably operatively regulates the diesel and liquefied gas flow control valves via the respective electronic control boards. The accelerometer inputs are preferably processed by the electronic control unit.
The ratio of LPG to diesel may vary between 50:50 and 90:10 respectively. More preferably the ratio of LPG to diesel is approximately 70:30 respectively. Preferably any ratio is suitable providing the engine components are not prematurely worn because of lack of lubricity and the manufacturer's warranties are not voided and the calorific value of the fuel is sufficient to allow the engine to produce an acceptable amount of power and torque.
The liquid fuel mixture is preferably pumped to a common rail operable under high pressure so that the liquid fuel mixture remains in a liquid state. The phrase common rail in the specification includes common rails and fuel rails. Preferably, the common rail is connected to an injector for each combustion chamber and the fuel mixture is distributed to each of the injectors for combustion in accordance with the manufacturer's specifications.
Preferably the fuel mixture is filtered prior to distribution in the common rail.
Excess unburnt fuel mixture is preferably collected in a overflow tank and returned to the mixing chamber for combustion in the combustion chamber. More preferably, excess fuel mixture is returned via a fuel temperature sensor to a fuel pressure limiter then to an overflow valve and a pressure limiting valve. Excess fuel is then preferably passed through a fuel cooler and maintained under pressure in a pressurized tank for subsequent reintroduction into the mixing chamber.
Preferably there is a separate line from the diesel tank to the supply pump and subsequently to the common rail for the engine to use diesel as the sole fuel source.
In another aspect the invention broadly resides in a method of using the above mentioned dual fuel system for an internal combustion diesel engine including
proportioning flow of liquefied gas from the first tank with the first proportioning valve means;
proportioning flow of diesel from the second tank with the second proportioning valve means;
mixing proportioned fuels to form a liquid fuel mixture in the mixing chamber;
distributing the liquid fuel mixture from the mixing chamber to each of the combustion chambers.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the present invention can be more readily understood and put into practical effect, reference will now be made to the accompanying drawings wherein:
FIG. 1 is a diagrammatic view of the preferred embodiment of the dual fuel system for diesel engines;
FIG. 2 is a diagrammatic top view of the mixing chamber using Swage Lock proportioning valves as an alternative to the electronic control system; and
FIG. 3 is a diagrammatic side view of the mixing chamber using Swage Lock proportioning valves as an alternative to the electronic control system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1 , there is shown a dual fuel system 10 for a diesel engine for trucks. Diesel is introduced from a service station pump at atmospheric pressure into tank 11 . In a first pathway, diesel is drawn from tank 11 along pipe 30 via an inline filter 12 by fuel feeder pump 13 . Fuel feeder pump 13 operates at a pressure of approximately 30 psi. The inline filter 12 is a glass filter that removes contaminants. The diesel fuel is subsequently pumped by supply pump 15 to the common rail 16 for entry into the combustion chamber via injectors 18 . With the first pathway, diesel is used as the sole fuel source for combustion within the combustion chamber of the engine.
In a second pathway, diesel is drawn from tank 11 by secondary fuel feeder pump 20 along pipe 31 . The diesel from tank 11 is filtered by the inline filter 12 as it is being drawn by the secondary fuel feeder pump 20 . From the secondary fuel feeder pump 20 , diesel is passaged through a non-return valve 17 to a secondary diesel pressure tank 21 . The pressure within the secondary diesel pressure tank 21 is maintained at approximately 100 psi. The secondary diesel pressure tank 21 has an approximately 43 litre capacity. The secondary diesel pressure tank 21 has a pressure switch 22 which electrically controls the secondary fuel feeder pump 20 thereby maintaining the desired pressure. The secondary diesel pressure tank 21 also has a bleed valve to bleed any air within the line 31 and secondary diesel pressure tank 21 . There is also a line 32 between the fuel feeder pump 13 and the secondary diesel pressure tank 21 to enable diesel passaging line 30 to enter the secondary diesel pressure tank 21 . There is a non-return valve 27 in line 32 that prevents diesel from the secondary diesel pressure tank 21 passaging to the fuel feeder pump 13 .
Pressurized diesel from the secondary diesel pressure tank 21 is passaged along line 33 to the mixing chamber 28 . The flow of pressurized diesel along line 33 is controlled by a diesel flow control valve 24 . The diesel control valve 24 is electrically operated by a diesel electronic controller 25 which in turn is actuated by the electronic control unit 26 . The electronic control unit 26 processes information regarding revolutions per minute of the engine from a crank angle sensor. Pressurized diesel passes through the diesel flow control valve 24 and enters the mixing chamber 28 at a pressure of approximately 100 psi.
LPG is introduced into tank 43 from a service station pump where the tank 43 is filled under the pressure of approximately 150 psi in liquid state. LPG is stored under pressure at 150 psi in liquid state. Liquid LPG passes through pipe 34 via shut off valve 44 , in line filter 45 , solenoid valve 48 and non-return valve 49 to an LPG flow control valve 50 . The LPG flow control valve 50 is electrically operated by a LPG electronic controller 51 which is actuated by the electronic control unit 26 . Pressurized liquid LPG enters the mixing chamber 28 at approximately 100 psi.
Both the pressurized diesel and liquefied LPG enter the mixing chamber 28 . The mixing chamber 28 is shown in both FIGS. 2 and 3 . As an alternative to the electronic control flow valve system, ¼ NPT Swage Lock Proportioning Valves 60 can be used and are preferably locked at a predetermined ratio setting.
The mixing chamber 28 is substantially spherical with the proportioning valves 60 are positioned spatially diagonally opposite each other. The mixing chamber 28 has an internal wire mesh 61 to facilitate mixing of the fuels. The mixed fuel is discharged via outlet 62 and excess mixed fuel is reintroduced via inlet 63 .
A preferred ratio of fuels is 30% diesel and 70% LPG. However, there is a range of ratios from 10% diesel and 90% LPG to 90% diesel and 10% LPG. Ratios of fuel blends which use less than 30% diesel can be achieved where the lubricity of the fuel mix is increased. In particular, low sulphur diesel which undergoes additional filtration treatment has reduced lubricity and fuel blends below a diesel percentage of 30% requires additional lubricity in order to maintain engine components.
Apart from regulating the diesel and LPG flow control valves 24 , 50 , in response to engine revolutions per minute, the flow control valves 24 , 50 are also regulated by accelerometer inputs which provide information regarding traveling up and down inclines. The accelerometer inputs are processed by the electronic control unit 26 .
From the mixing chamber 28 the liquid fuel mixture is drawn through a secondary fuel filtration unit 54 by the supply pump 15 . From the secondary fuel filtration unit 54 , the liquid fuel mixture is drawn into the supply pump 15 and pumped to the common rail 16 at high pressure. The common rail 16 distributes the liquid fuel mixture to the injectors 18 of each combustion chamber (not shown). Only one injector 18 is shown in FIG. 1 by way of example. There is also a fuel pressure sensor 55 associated with the common rail 16 .
Excess fuel mixture that is not burnt is returned from each injector 18 via a fuel temperature sensor 56 . Excess fuel mixture associated with the common rail 16 is returned via pressure limiter 57 . Excess fuel mixture is piped to the overflow valve 58 through pressure limiting valve 59 , fuel cooler 64 to the mixed fuel pressure tank 65 . The mixed fuel pressure tank 65 has a bleed valve 66 which allows removal of air from the fuel lines and tank 65 . From the mixed fuel pressure tank 65 , the fuel mixture is drawn up into the mixing chamber 28 for return to the common rail 16 and combustion chambers.
Emission Test Results
By way of providing support for the dual fuel system of the current invention, emission tests were conducted by an independent third party, Brisbane City Council and the results were analyzed by Gilmore Engineers Pty Ltd. Two tests were conducted when the vehicle used diesel only and LPG/diesel (at a ratio of 70% LPG and 30% diesel). The diesel only test (test 2969) was conducted on 27 Mar. 2007 using the DT80 short test. The LPG/diesel test (test 3262) was conducted on 17 May 2007 using the DT80 short test. The same vehicle was used for both tests. The vehicle was an ISUZU (950 FVR) truck with a vehicle test mass of 13000 kg. The DT80 short test was a series of rapid accelerations and decelerations interspersed with idling and is designed to evaluate vehicle emissions during typical “real world” stop start operating modes and conditions.
The emission test results are summarized below:
DIESEL ONLY
LPG/DIESEL
DNEPM
UNITS
(Test 2969)
(Test 3262)
Limits
NO x
g/kWh
6.211
0.380
(Nitrous
g/km · t
0.707
0.686
1.5
Oxide)
PM LLSP
mg/kWh
80.194
26.325
(Particulate
mg/km · t
9.126
2.831
50
Matter)
Average
%
4.623
2.382
25
Opacity
Based on these results, an engine under the DT80 short test driving cycle using the LPG/diesel fuel mixture has significantly lower opacity, significantly lower particulate emissions, and lower NO x emissions on a per km basis in comparison with diesel.
The NO x emissions using the LPG/diesel mixture are only 45.7% of that allowable by the DNEPM (Diesel Vehicle Emission National Environment Protection Measure) limits. Particulate matter emissions are only 5.7% of that allowable by DNEPM limits and average opacity is 9.5% of that allowable by DNEPM limits. In summary, the emission levels using LPG/diesel mixture are substantially lower than that allowable by DNEPM limits.
ADVANTAGES
The preferred embodiment of the dual fuel system has the advantage that LPG can be mixed with diesel at comparatively high ratios and used as a liquid fuel mixture in the combustion chamber. Unlike other dual fuel systems, the diesel manufacturer's specifications are not altered and manufacturer's warranties are maintained. The advantage of the preferred embodiment arises from mixing liquid LPG and diesel to form a liquid fuel mixture which can be distributed via the common rail to the combustion chambers. Other dual fuel systems use LPG in a gaseous state often introducing LPG with the induction air.
The advantage of the dual fuel system of the preferred embodiment is that only minor changes are required to the diesel engine, a cleaner emission is produced and less frequent servicing including oil changes is required. The dual fuel system of the preferred embodiment takes advantage of the relative cheapness and abundant supply of LPG compared with diesel and petrol fuels. This relative cheapness can be translated into operational cost savings for vehicles with diesel engines.
VARIATIONS
It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is herein set forth.
Throughout the description and claims this specification the word “comprise” and variations of that word such as “comprises” and “comprising”, are not intended to exclude other additives, components, integers or steps. | The present invention is directed to a dual fuel system and a dual fuel system assembly where liquid LPG and diesel are mixed and then distributed via the common rail to the combustion chambers. The liquid fuel mixture remains in a liquid state and under pressure for introduction to the combustion chambers. With the preferred embodiment of the dual fuel system, only minor changes are required to the diesel engine without altering the manufactures specifications and voiding the manufacturer's warranties. The resultant combustion of the liquid fuel mixture provides a cleaner emission and relatively cheaper vehicle operational costs. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a vehicle mounted refuse collection apparatus and, more particularly, to a vacuum type collector apparatus especially adapted for use in cleaning out sewers, sludge basins, and the like in which both particulate matter and liquids are present.
For cleaning out sewers, for example, it has proven efficient to have both a collecting or vacuum apparatus and a refuse storage tank combined on a single vehicle and adapted to be transported to the clean-up site, and after clean-up to be transported to a suitable waste disposal site. Examples of such arrangements are disclosed in U.S. Pat. Nos. 4,111,670 of DeMarco, 4,227,893 of Shaddock, 4,199,837 of Fisco, Jr., 4,234,980 of DiVito et al, and 4,160,302 of Hirst et al.
For the heavy duty cleaning out of sewers and the like, it has been found desirable to inject water under pressure into the sewer or element to be cleaned out and the water transports the refuse from the sewer to the storage tank. In most cases the water can be separated from the refuse and discharged from the storage tank to the sewer. To insure an adequate supply of water at the job site, it is desirable to include along with the refuse collecting unit and storage tank a water tank of sufficient capacity. The water tank can be mounted on the vehicle together with a pump and other suitable apparatus for introducing the water from the water tank into the sewer or element to be cleaned. Examples of various arrangements for accomplishing this are shown in the aforementioned Fisco, Jr., DiVito et al, and Hirst et al patents, as well as in U.S. Pat. Nos. 4,207,647 of Masters and 4,322,868 of Wurster.
In the known prior art arrangements, the vehicle is driven to the site where clean-up is to take place, one end of a vacuum hose carried by the vehicle on a boom arrangement is lowered into the sewer and the refuse is vacuumed up through the hose and into the refuse storage tank. Various arrangements are provided within the refuse storage tank for separating the refuse from the air stream so that the tank becomes filled with the refuse and the air is discharged to the atmosphere. When loaded with refuse, the vehicle is transported to a suitable waste deposit site and the entire tank is tilted to empty it. Where water is used to facilitate the cleaning process, means generally are provided to separate the water from the refuse, which allows dumping the water back into the sewer.
All of such systems have shortcomings. For example, the tilting of a refuse laden carrier requires expensive heavy duty tilting mechanisms for raising the front of the refuse storage chamber and which create an electrical shock hazard when in the vicinity of overhead power lines. Where the vehicle is equipped with a water tank, not only is an additional complication produced in the tilting operation, but a problem of weight distribution is presented. In most cases where tilting is used to empty the refuse storage tank, it is necessary to uncouple the hoses or conduits connected to the tank before the refuse tank is tilted.
The weight distribution problem created by the addition of a water storage tank can best be appreciated by an example. Where the water storage tank is mounted in front of the refuse storage tank, as the vehicle is being driven to the collection site, the greatest percentage of the load carried by the vehicle is due to a full water tank, while the refuse tank is empty. This places a higher percentage of the vehicle weight on the front wheels and tends to overload the front wheels. After the clean-up, the opposite situation prevails, since the water tank is now virtually empty and the refuse tank is full, thereby placing the greatest portion of the weight over the rear axle or axles of the vehicle. If the water tank is either above or below the refuse tank, there likely is produced a top-heavy condition, either en route to the site, or en route to the waste dump, which can be dangerous while the vehicle is moving.
In the vacuum process, an air pump is used to create the vacuum, and usually such pump is located at or near the discharge point of the air to the atmosphere. If particulate matter remains in the air stream after passage through the refuse collection tank, the particulate matter can damage or clog the pump, as well as be discharged into the surrounding atmosphere. In an effort to cleanse the discharge air, sometimes filters are use, in some cases comprising a multiplicity of filter bags contained in a housing located between the refuse tank and the air pump. Such an arrangement is shown, for example, in the Shaddock patent. A problem arises with such bags, however, in that they accumulate particulate matter and commence to impede the air flow after a time, thus it is necessary to clean and replace such bags. Replacement of the bags in accordance with prior art methods entails lifting the bags out of the housing, which results in the dislodging and deposit of some of the particulate matter in a region of the housing that is normally in the path of filtered air flow, with the net result that in operation, the discharged air may contain some remnants of the refuse which can damage the air pump.
The prior art vacuum refuse collection vehicles generally are unitary in nature, and, once designed, are limited to the sizes and capacities incorporated in the design specifications. The inflexibility of capacities of the design is likely to result in an arrangement of insufficient capacity for some applications, or of too much capacity for other applications or a mismatch of water storage capacity with refuse storage capacity for a particular job requirement.
It is therefore, an object of the present invention to eliminate the necessity of tilting the entire container assembly, thereby resulting in a relatively simple structure that does not require expensive tilting machinery and does not require disconnection of the various pipes and hoses from the refuse collection tank prior to tilting.
It is another object of the invention to provide a water storage tank on the refuse collection vehicle for carrying a supply of water along with the refuse collecting tank in such a manner that weight shifts and imbalances are minimized and the axial loading of the vehicle remains relatively constant as the water supply is depleted and the waste is collected.
Still another object of the invention is to provide a filter bag housing and bag mounting arrangement that reduces the likelihood of waste matter being deposited in the region of filtered air flow when the bags are removed for replacement or cleaning.
Another object of the present invention is to provide a semi-modular construction for a refuse collecting vehicle whose size and capacity can be customized for the particular use to which the vehicle is to be put.
SUMMARY OF THE INVENTION
These and other objects, features and advantages are realized in the present invention which comprises a vacuum refuse collecting vehicle which includes a waste receiving and transporting chamber and a water transporting chamber combined in a unitary cylindrical tank, with the longitudinal axis of the cylindrical tank extending along the length of the vehicle. A sloped dividing wall or septum extends from the top front of the tank interior to the rear bottom of the tank interior and divides the tank into two parts, the front portion forming the water chamber and the rear front portion forming the water chamber and the rear portion the refuse containing chamber. Because of the sloped dividing wall in the tank the weight distribution of the water and refuse in the tank does not shift significantly in a longitudinal direction as the water supply is decreased and the volume of refuse is increased, thereby insuring a relatively constant axial loading. Furthermore, the instability that might arise from a top heavy condition is minimized because the sloped wall tends to cause the heavier waste or refuse to move toward the lower portion of the tank.
The cylindrical tank is capped at each end by closure members, which in the preferred embodiment is clamshell shaped, the closure member adjacent the rear of the tank being hinged at the top of the tank and tiltable upwardly for emptying the refuse from the tank. The dividing wall has a slope of from approximately 37° to 52° from front to rear, and the dividing wall is made of a material such as plastic, mild steel or stainless steel down which the refuse slides toward the rear. Thus, when the rear clamshell enclosure member is tilted upward, the refuse slides down the sloped wall and out of the tank, emptying the tank and the refuse in the clamshell closure member drops downwardly out of the closure member.
Where greater capacity is required, either for more water or more refuse, cylindrical spacer members can be inserted in the cylindrical wall of the and so as to lengthen the tank, deeper or shallower clamshells can be used at the ends of the tank, and the slope of the dividing wall can be changed.
A suction conduit is mounted on a movable boom above the and with one end in communication with the refuse collection chamber of the tank and the other end mounted on a boom. A flexible section of the suction conduit permits movement of the conduit laterally and vertically. Additional lengths of conduit are carried on a rack mounted on the vehicle so that the boom carried conduit may be lengthened for insertion into deep sewer mains. The conduit extends downwardly at one end of the vehicle for insertion into the area to be cleaned.
Mounted on the vehicle is a water hose reel and hose which is supplied with water from the water tank through a suitable water pump. The end of the hose to be inserted into the sewer has mounted thereon a nozzle with backwardly oriented jet openings so that the water moving through the jet openings tends to drive the nozzle forward while, at the same time liquefying or softening the waste in the sewer. The hose and reel can be mounted on either the front or the rear of the vehicle.
A vacuum pump causes the end of the conduit within the sewer to function as a vacuum cleaner, sucking up the refuse and sludge loosened up with the aid of the water jets. The waste material, liquid and air pass through the suction conduit into the refuse storage tank and in some models through a cyclone separator which separates the refuse from the air stream. An exhaust conduit leads from the refuse collection chamber at the top of the tank to the bottom of one or more bag filter housings and the exhaust air flow is further cleared of waste matter as it passes upward through the filter bags. At the top of one of the bag filter housings the air stream is directed downward through a steel microstrainer into a conduit leading into the vacuum pump, from which it is directed into a silencer and then into the atmosphere.
Each of the filter bags is retained in place by a spring steel band sewn in the cuff at the upper end portion of the bag which holds the cuff in place in an opening formed in a tube support sheet at the top of its housing, and the bags are prevented from collapsing by a metallic framework inserted in each bag. When the bags become dirty or clogged, the bag framework is removed and the bags are dropped down through the holes in the tube support sheet. Access doors at the bottom of the bag housing or housings permit access to the lower portions of the bags, and also permit cleaning of the accumulation of waste in the bottom of the housing caused by reverse air flow pulsing through the bags to maintain the bags in a clean condition.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the present invention will be more readily apparent from the following detailed description, read in conjunction with the accompanying drawings, in which:
FIG. 1 is a side elevation, partially cutaway view of a vehicle embodying the principles of the present invention;
FIG. 2 is a plan view of the vehicle of FIG. 1;
FIG. 3 is a cross-sectional elevation of the filter bag housings of the present invention;
FIG. 4 is a cross-section along the line IV--IV in FIG. 3;
FIG. 5A is a view of a filter bag used in the housings of FIG. 3;
FIG. 5B is a view of a stiffener member for use with the filter bag of FIG. 5A;
FIG. 6 is a side elevation of a second embodiment of the invention, with the reel and hose mounted in a recess of the rear clamshell closure, and the suction conduit extending to the rear of the vehicle;
FIG. 7 is a partial plan view of the vehicle of FIG. 6;
FIG. 8 is a side elevation of a third embodiment of the invention, with the hose mounted on a reel having its axis of rotation extending along the length of the vehicle;
FIG. 9 is a partial plan view of FIG. 8; and
FIGS. 10 and 11 are a schematic diagram of the power take-off system that drives the air pump and water pump from the vehicle engine.
DETAILED DESCRIPTION
Referring now in more detail to the drawings, in which like numerals indicate like features throughout the several figures, FIGS. 1 and 2 depict a vacuum refuse collecting vehicle 10 embodying the principles of the present invention. As shown in FIGS. 1 and 2 vehicle 10 comprises a ten-wheel double rear axle truck chassis and cab 11 upon which is mounted and affixed thereto a cylindrical tank member 12 of suitable material such as, for example, steel, approximately seven to eight feet in diameter. The length of tank 12 is chosen to provide sufficient capacity for the anticipated use. For example, for large capacity work the tank may be approximately nine and one-half feet in length, whereas for smaller capacity it may be six and one-half feet in length. Within tank 12 and extending from the top front edge of the tank to the bottom rear edge thereof is a sloping septum or divider wall 13 preferably of mild or carbon steel or stainless steel, which has the property of presenting a small amount of friction to objects sliding down its sloped upper surface. While other materials can be used, it is important that the divider wall 13 have a low coefficient of friction so the refuse easily moves down its upper surface. Divider wall 13 is welded in place to produce two separate, non-communicating compartments 14 and 16 within the tank 12. Inasmuch as divider wall 13 extends from the top front edge of tank 12 to the bottom rear edge thereof, its angle of slope is likely to vary with the length of tank 12. Thus for the long tank, the slope is at least 37°, while for a shorter tank the slope is steeper, for example, 52°. As will be apparent hereinafter, a change in the slope of the divider wall changes the capacities of the compartments 14 and 16, and the slope should be steep enough to assure the downward movement of the refuse in the refuse compartment 16.
The front end 17 of tank 12 is sealed by a convex or clamshell-shaped end wall 18 which is fixed in place, while in the embodiment shown in FIG. 1, the rear end 19 of tank 12 is sealed by a closure member or tail gate 21 comprising a cylindrical spacer member 22 and a convex or clamshell shaped end wall 23. As was pointed out in the foregoing, normally annular rim 19 of the tank is sealed to annular rim 20a of end wall 23. Where greater capacity is desired, spacer member 22 is inserted between end wall 23 and its rim 20 and is affixed to wall 23 as by welding or other suitable means which will provide a hermetic seal. In a similar manner, where greater capacity in water chamber 14 is desired, a spacer (not shown) may be added between end 17 of cylindrical tank 12 and end wall 18.
Closure member 21 is hinged to tank 12 by a pair of hinges 24 and 26 which are offset from the center line of tank 12, as best seen in FIG. 2, which reduces the overall height of the assembly and which stabilizes the door movement. In addition, a plurality of hydraulic latches 27 placed about the abutting rims 19 and 20a serve to clamp end closure member 21 securely to end of tank 12. A pair of hydraulic cylinder and piston assemblies 28 and 29 are connected between the outer wall of tank 12 and outer wall of closure member 21, near the top of the tank, as shown in FIGS. 1 and 2. When latches 27 are unlatched and hydraulic members 28 and 29 are actuated, closure member 21 is tilted upward from the bottom about the axis of hinges 24 and 26, thereby opening the assembly at the bottom of end 19 of tank 12, permitting the accumulated refuse in refuse chamber 16 and in the tilted end closure wall 23 to be dumped out. Sloped divider wall 13, preferably being of stainless steel, presents little friction to the refuse so that the refuse easily slides down the slope thereof and out the opening, thus emptying compartment 16 without the necessity of tilting tank 12.
For simplicity, the various hydraulic hoses and connections for hydraulic cylinder assemblies 27, 28 and 29 have not been shown in FIGS. 1 and 2. The hydraulic fluid is contained in hydraulic tank 31, and the hydraulic pressure is supplied by a motor and hydraulic pump assembly 32 mounted on the vehicle.
Mounted on top of hydraulic fluid storage tank 31 is a circular gear and bearing assembly 33 which has mounted thereon a boom 34 which extends out over the cab 36 of the vehicle 10. Boom 34 is moved and positioned by hydraulic cylinder and piston assemblies 37 and 38 which can move the boom 34 in azimuth, length and elevation to any desired position within the limits of travel of the pistons of assemblies 37 and 38. As was the case with hydraulic cylinder assemblies 28 and 29, the hydraulic connections to hydraulic cylinder assemblies 37 and 38 have not been shown for simplicity, but it is to be understood that they are controlled by hydraulic fluid from pump assembly 32. Pump assembly 32 is in turn controlled by an electrical control box 39 and actuator 41 which are attached to hose rack 42 on the front of the vehicle, the details of which will be discussed more fully hereinafter.
Vacuum conduit 43 communicates at one of its ends with cyclonic ring separator 49 at the top of tank 12 so that the refuse moving through the conduit 43 with air into refuse collection chamber 16 of the tank is separated from the high velocity air stream, allowing the refuse to fall into the tank compartment 16. The vacuum conduit 43 moves the refuse and fluid into the outer concentric space formed by outer wall 45a of the cyclonic ring and inner wall 45b, which causes a circular movement of the fluid and refuse, moving the heavier particles to the outside by centrifugal force. Exhaust conduit 52 extends concentrically up through the inner wall 45b, up through the tank 12 and then forwardly to the bag houses 57 and 58. Vacuum conduit 43 which extends from within the refuse collecting chamber 16 of tank 12 is mounted on top of boom 34 and projects beyond the end of boom 34. Because one end of conduit 43 is fixedly mounted to tank 12, it includes a flexible section 44 which enables it to move with boom 34 when the latter is placed in operative position. The free end 46 of conduit 43 is adapted to be inserted in a manhole or within the sewer to function as a vacuum cleaner. Additional lengths 47 of conduit are carried on a rack 48 and are readily attachable to the free end 46 of conduit 43 to increase its length as necessary.
Exhaust conduit 52 extends upwardly from the center of cyclonic ring separator 49 through the top of the tank 12 and turns at a right angle to extend forwardly of the vehicle, and then is turned downwardly in front of the tank to the lower portion of filter bag housing 57, into which the exhaust air stream is introduced (FIG. 3). A second filter bag housing 58 may be coupled to housing 57 by an air cross over passage 59. Second bag housing 58 is for use in higher volume air flow applications, and may be eliminated when desired. The exhaust air from conduit 52 passes upwardly through a plurality of filter bags 62 in housing 57, and upwardly through bags 62 in housing 58. The waste material is collected on the surfaces of the bags. Housing 58 is joined to housing 57 at the top by an air cross over duct 63 so that the filtered air from housing 58 mingles with the filtered air in housing 57 and all of the air then passes downward through a microstrainer 64 and duct 66 and exits from housing 57 into a duct 67 which leads to an air pump or blower 68 (FIG. 2). Blower 68 may be driven by the vehicle motor through suitable gearing, described hereinafter. The filter bag housings 57 and 58 are provided with clean-out doors 69 and 71. A level detector 70 (FIG. 3) is mounted in the lower portion of one of the filter bag housings and functions to deactivate the operation of the system upon detecting a high level accumulation of material in the bag house. In addition, a float shut off valve (not shown) can be used to close the air inlet 45b (FIG. 1) so that the rising level of liquid waste would automatically close the flow of fluid from tank 12 to bag house 57.
The exhaust air passes from air pump 68 through a duct 72 into the bottom of a silencer member 73 from which the air is discharged into the atmosphere.
Hose rack 42, which is mounted on the front of vehicle 10, carries a hose reel 74 rotatively mounted thereon and which contains a plurality of turns of high pressure water hose 76. In operation, the free end of hose 76 has mounted thereon a water jet driven nozzle, not shown, which is introduced into the sewer to supply a high velocity water stream for softening and at least partially liquefying the refuse, and also for washing out the sewer pipes. The water supply for hose 76 is contained in chamber 14 of the tank 12 and is pumped through water pump 77 to the hose 76. For simplicity, the connections between compartment 14 and pump 77, and between pump 77 and hose 76 have not been shown, it being understood that they are conventional in the art. A gear case 78 connected to water pump 77 is used to govern the velocity and pressure of the water, and may be driven by the vehicle motor or by auxiliary engine.
A hydraulically powered sludge pump 312 is removably mounted to a platform 313 mounted to the front of the vehicle. The sludge pump is used in conjunction with the vacuum collecting system when it is desired to clean thick liquid material such as mud which is normally too thick to be pulled into the system by the vacuum alone. A winch 314 having a cable 315 and a hook 316 is mounted to the boom 34. The winch 314 includes a motor and motor control valves (not shown) and is adapted to raise and lower the hook to the sludge pump 312 to which the hook 316 is attached. The sludge pump 312 can then be lifted by the winch and moved through articulation of the boom 34 to an operative location such as in a sludge pond. When in an operative position the sludge pump is coupled with the free end 46 of the conduit 43 and to the hydraulic pump 32 via hydraulic lines (not shown). When activated, the sludge pump acts to pump the mud or other sludge-like material into the conduit where it can be collected and processed by the system in the normal way.
FIGS. 3 and 4 depict in greater detail the filter housing arrangement, including both filter housings 57 and 58, ducts 52 and 66, and ducts 59 and 63, and also show the directions of the air flow therethrough. Filter bags 61 and 62 are mounted in housings 57 and 58 respectively by means of tube support sheets 81 and 82 respectively, which are affixed to the interior walls of housings 57 and 58. As can be seen in FIG. 4, tube support sheet 81 has a central aperture 83 defining the top of duct 66 and into which is inserted microfilter 64. Radially disposed around aperture 83 are a plurality of apertures 84, into which filter bags 61 are fitted. Tube sheet 82 likewise has a plurality of apertures 86 for receiving bags 62, but does not have a central aperture.
Because of the force of the air passing through the housings 57 and 58, bags 61 and 62 ordinarily would tend to collapse and cease to function properly. In FIGS. 5A and 5B there is shown a preferred arrangement for preventing such collapse. The filter bags 61, 62 of FIG. 5A are formed of a suitable cloth filtering material, such as Dacron®, polypropylene, or polyethylene. The top of each bag is formed with a soft collar 90 with spaced annular flanges 87 and 88, leaving an annular groove 89 therebetween. A spring steel band 91 is positioned in the soft collar so that the collar tends to retain its circular shape but is collapsible when pressed inwardly. The collar is of greater diameter than its aperture 84 in the tube sheet 81, while the diameter of the groove 89 is slightly less than the diameter of one aperture 84, thus bags 61 and 62 can be snapped into place in an aperture 84 and firmly held there.
A stiffening member 92 comprises a metallic ring 95 to which a plurality of rods 93 are fastened, with the rods extending downwardly to form a cage-like structure that fits into and distends the filter bags 61, 62. The ring 95 at the top of the stiffening member rests on the upper surface of the tube support sheet 81. Thus stiffening member 92, when in place within the filter bag, prevents the bag from collapsing during operation.
As shown in FIG. 3, housings 57 and 58 have covers 65 which are hingedly attached to the housings so as to be openable as indicated by the arrows. This configuration provides convenient access to the upper portion of the interiors of the housings for bag replacement. Usually, when it is desired to replace the filter bags, the covers are opened and the bags are saturated with water to prevent any hazardous dried material, such as asbestos particles, from bellowing out of the filter bags into the atmosphere as the bags are disconnected. The saturated depleted filter bags can then be disconnected from their supporting apertures by removing the stiffening member 92 (which is relatively clean) from the top, collapsing the collar 87 by hand and allowing the bag to drop to the bottom of the housing where they can be removed through doors 69 and 71 and bagged along with the accumulated asbestos. Removing the bags from the bottoms of the housings is far superior to removing them from the top because with the later method, the refuse clinging to the outside of the bag tends to contaminate the "clean" area of the upper housing. This dirt can be accidentally sucked into the close tolerances of the positive displacement pump damaging the pump or be emitted through the pump silencer becoming a nuisance or environmental hazard. Removal from the bottom of the housing eliminates this risk.
FIGS. 6 and 7 illustrate a modified embodiment of the invention whereby the boom and suction hose are directed to the rear of the vehicle and the water hose and reel are mounted to the rear closure of the tank. Boom 134 is mounted to the top of the tank 112, with suction hose 143 being mounted to boom 134. As with FIG. 1, the suction hose 143 communicates at one of its ends with the refuse collection chamber 116, and the other distal end projects beyond the boom 134.
Water hose 176 is collected on water hose reel 174 with the reel being supported by support 177 mounted to the rear clamshell closure 121 of the tank 112. The reel 174 projects into a recess formed in the clamshell closure 121. When the closure 121 is pivoted upwardly by the action of hydraulic cylinders 128 and 129, the reel 174 is moved in unison with the clamshell closure 121 so that it is out of the way during the dumping function of the vehicle.
Exhaust conduit 152 has one of its ends located interiorly of the waste collection chamber 116, and in this embodiment, the conduit extends through the divider wall 113, passes through the upper portion of water chamber 114, out through the clamshell end closure 118, turns downwardly and then forwardly for connection to the filter bag house, as described with respect to FIGS. 1-5.
FIGS. 8 and 9 show another embodiment of the invention, whereby hose reel 274 and its water supply hose 276 are mounted to the rear closure of the vehicle. The reel is held at a right angle orientation, with the axis of rotation of reel extending lengthwise of the vehicle. The reel is rotatably mounted on its support 277 to the rear member 221 of the tank 212. The suction conduit 243 and boom 234 are substantially the same in construction and operation as described in FIGS. 6 and 7.
Also shown in FIG. 8 is a hingedly attached clamshell panel 290 that covers a correspondingly shaped opening in the rear member 221. A beam 291 is attached at one end to the panel 290 and at its other end to the top portion of the rear member 221. A hydraulic cylinder 292 is mounted to push the beam 291 upwardly with its upper attachment pivoting upon expansion of the cylinder to cause the panel 290 to open up such that collected material within the chamber can be dumped. A locking mechanism 293 is constructed to lock the panel 290 securely in its closed position during operation of the system such that material within the chamber does not accidentally leak or the panel accidentally open.
In some instances the hood of the engine compartment of the vehicle tilts forwardly when the hood is to be opened. If the reel and water hose are mounted to the front of the vehicle as illustrated in FIGS. 1 and 2, it is difficult to open the hood while the reel is in its proper location, and the reel might have to be tilted or dismounted from the vehicle in order to tilt the hood forwardly. Also, when the engine of the vehicle is in operation, the forwardly mounted hose and reel and related apparatus tends to interfere with the flow of air through the radiator of the vehicle. Thus, a larger capacity radiator might be necessary for proper operation of the vehicle.
In order to avoid the problems mentioned above, the mounting of the reel and its hose to the rear of the vehicle as illustrated in FIGS. 6-9 can be provided at the request of the customer.
As illustrated schematically in FIGS. 10 and 11, the power take-off system for the components of the vacuum collector system derive their power from the vehicle engine. As illustrated in FIG. 11, a transfer case 101 is mounted in driving relationship with respect to the drive shaft 102 of the vehicle, and rotates its output shafts through clutches 104 and 106. Clutch 106 operates air pump or blower 68. Clutch 104 operates water pump 77 through the belt and sheave connection 105.
OPERATION
In operation, the vehicle 10 is driven to the cleanup site, for example, a clogged sewer, with compartment 14 filled with water and compartment 16 empty. At the site, the hose 76 equipped with a suitable nozzle and the duct 43 are lowered into the sewer and the water pump 77 and air pump 68 are started. The nozzle and hose are pulled into the sewer by recoil of the rear firing jets of the water existing the nozzle. As the high pressure water liquefies or loosens the material in the sewer the material is sucked up and carried through duct 43 and discharged at high velocity into chamber 16. The material thus discharged passes through the cyclone ring 49 so that the heavier material tends to fall downwardly in the refuse collection chamber, and the air is drawn from the chamber 16 through duct 52 and passed to the bag housings 57 and 58 where it is filtered, as explained heretofore. As refuse collection chamber 16 is filled with the waste matter which contains a large amount of water, some of the water can be drawn off through a perforated standpipe 96 which communicates with the exterior of tank 12 through a suitable valve 97, 197 when the pressure in the refuse collection chamber 16 is at atmospheric pressure. The perforations in standpipe 96 are small enough to prevent most solid matter from passing therethrough, but large enough to permit water to pass.
The level detector 70 in bag house 57 senses the level of refuse in the lower portions of the bag house and operates to terminate the suction function of the system, either by disengaging the clutch 106 of the air pump or by opening a bypass valve (not shown). The levels of waste in the lower portion of the bag houses generally correspond to the level of refuse in collection chamber 16, so that the detector switches provide a safe and inexpensive shut down system.
After the clean-up process is completed, refuse collection chamber 16 is substantially full, and compartment 14 is substantially empty. Thus there is a shift of weight toward the rear of the vehicle. However, because of the slope of internal wall 13, the actual center of gravity shifts enough to reduce the loading on the front axle thus increasing the overall machine legal load carrying capacity as it relates to state and federal law including the bridge laws.
While the operation has been explained in connection with wet cleaning, the vehicle 10 can be used for cleaning up dry materials as well. In addition, the distal end of vacuum duct 43 can be fitted with an integral hydraulically driven sludge pump as previously described for cleaning out sludge deposits, ponds, and the like.
When the vehicle is driven to a dump site, the rear clamshell end wall 23 is tilted up on hinges 24 or 26 and the collection of waste material in the concave space of the clamshell end wall falls from the clamshell end wall and the waste material inside the compartment 16 slides down the sloped divider wall 13 and falls out the rear of the compartment 16. With this arrangement the tank 12 does not have to be tilted to dump the collected waste material.
The foregoing illustrates the principles of the invention in a preferred embodiment thereof. Numerous modifications or changes may occur to workers in the art without departure from the spirit and scope of the invention. | A vacuum refuse collecting vehicle has a tank divided into two hermetically sealed compartments by an internal sloped wall. The forward compartment functions as a water tank and the rear compartment as a waste containment tank. The capacity of the compartments can be increased by the addition of spacers to the cylindrical tank to make the tank longer, by changing the angle of the internal sloped wall, or by changing the depth of the concave end walls of the tank. The rear compartment is equipped with an upwardly tilting hinged concave tail gate for emptying the waste therefrom. The airstream which deposits the waste material in the tank is directed out of the tank into one or more bag filter housings, through an air pump, a silencer, and then to the surrounding atmosphere. The bag filters are so mounted and constructed that they may be removed through the bottom of the housings, thereby maintaining the upper portions of the housings substantially free of waste material. | 4 |
RELATED APPLICATIONS
This application is a continuation of PCT/US2010/035331, filed May 18, 2010, which claimed priority to U.S. Provisional Application Ser. No. 61/179,995, filed May 20, 2009, U.S. Provisional Application Ser. No. 61/218,832, filed Jun. 19, 2009, and U.S. Provisional Application Ser. No. 61/226,877, filed Jul. 20, 2009. The complete disclosure of each of these applications is hereby incorporated by reference herein.
BACKGROUND
Processing hydrocarbon-containing materials can permit useful intermediates or products to be extracted from the materials. Natural hydrocarbon-containing materials can include a variety of other substances in addition to hydrocarbons.
SUMMARY
Systems and methods are disclosed herein for processing a wide variety of different hydrocarbon-containing materials, such as light and heavy crude oils, natural gas, bitumen, coal, and such materials intermixed with and/or adsorbed onto a solid support, such as an inorganic support. In particular, the systems and methods disclosed herein can be used to process (e.g., crack, convert, isomerize, reform, separate) hydrocarbon-containing materials that are generally thought to be less easily processed, including oil sands, oil shale, tar sands, and other naturally-occurring and synthetic materials that include both hydrocarbon components and solid matter (e.g., solid organic and/or inorganic matter).
Such materials can be especially difficult to mix with liquids, e.g., with water or a solvent system during processing. For example, if the materials are low density, the materials tend to float to the surface of the liquid, or if the materials are high density they tend to sink to the bottom of the mixing vessel, rather than being dispersed. In some cases, the materials can be hydrophobic, highly crystalline, or otherwise difficult to wet. At the same time, it is desirable to process the feedstock in a relatively high solids level dispersion, for efficiency and in order to obtain a high final concentration of the desired product after processing.
The inventors have found that dispersion of a feedstock in a liquid mixture can be enhanced, and as a result in some cases the solids level of the mixture can be increased, by the use of certain mixing techniques and equipment. The mixing techniques and equipment disclosed herein also enhance mass transfer. In particular, jet mixing techniques, including for example jet aeration and jet flow agitation, have been found to provide good wetting, dispersion and mechanical disruption. By increasing the solids level of the mixture, the process can proceed more rapidly, more efficiently and more cost-effectively, and the resulting concentration of the intermediate or product can be increased.
In some implementations, the process further includes treating the feedstock to facilitate recovery of the hydrocarbon. For example, exposure of the materials to particle beams (e.g., beams that include ions and/or electrons and/or neutral particles) or high energy photons (e.g., x-rays or gamma rays) can be used to process the materials. Particle beam exposure can be combined with other techniques such as sonication, mechanical processing, e.g., comminution (for example size reduction), temperature reduction and/or cycling, pyrolysis, chemical processing (e.g., oxidation and/or reduction), and other techniques to further break down, isomerize, or otherwise change the molecular structure of the hydrocarbon components, to separate the components, and to extract useful materials from the components (e.g., directly from the components and/or via one or more additional steps in which the components are converted to other materials). Radiation may be applied from a device that is in a vault. Methods of treating hydrocarbon-containing materials are described in detail in U.S. patent application Ser. Nos. 12/417,786 and 12/417,699, both of which were filed on Apr. 3, 2009, the complete disclosures of which are incorporated herein by reference.
The systems and methods disclosed herein also provide for the combination of any hydrocarbon-containing materials described herein with additional materials including, for example, solid supporting materials. Solid supporting materials can increase the effectiveness of various material processing techniques. Further, the solid supporting materials can themselves act as catalysts and/or as hosts for catalyst materials such as noble metal particles, e.g., rhodium particles, platinum particles, and/or iridium particles. The catalyst materials can increase still further the rates and selectivity with which particular intermediates or products are obtained from processing the hydrocarbon-containing materials. Such additional materials and their use in processing are described in the above-incorporated U.S. patent application Ser. No. 12/417,786.
Many of the intermediates or products obtained by the methods disclosed herein, such as petroleum products, can be utilized directly as a fuel or as a blend with other components for powering cars, trucks, tractors, ships or trains. The hydrocarbon products can be further processed via conventional hydrocarbon processing methods. Where hydrocarbons were previously associated with solid components in materials such as oil sands, tar sands, and oil shale, the liberated hydrocarbons are flowable and are therefore amenable to processing in refineries.
In one aspect, the invention features a method that includes processing a hydrocarbon-containing feedstock by mixing the feedstock with a liquid medium in a vessel, using a jet mixer.
Some embodiments include one or more of the following features. The jet mixer may include, for example, a jet-flow agitator, a jet aeration type mixer, or a suction chamber jet mixer. If a jet aeration type mixer is used, it may be used without injection of air through the mixer. For example, if the jet aeration type mixer includes a nozzle having a first inlet line and a second inlet line, in some cases both inlet lines are supplied with a liquid. In some cases, mixing comprises adding the feedstock to the liquid medium in increments and mixing between additions. The mixing vessel may be, for example, a tank, rail car or tanker truck. The method may further include adding an emulsifier or surfactant to the mixture in the vessel.
In some instances, the vessel is or includes a conduit or other structure or carrier for the feedstock. For example, a jet mixer may be disposed in a conduit, e.g., between processing areas. In this case, the jet mixer can serve the dual purpose of mixing and conveying the mixture from one area to another. Additional jet mixers can be disposed in other areas, e.g., in one or more processing tanks, if desired. In some cases, the vessel can be a continuous loop of pipe, tubing, or other structure that defines a bore or lumen, and jet mixing can take place within this loop.
In another aspect, the invention features processing a hydrocarbon-containing feedstock by mixing the feedstock with a liquid medium in a vessel, using a mixer that produces generally toroidal flow within the vessel.
In some embodiments, the mixer is configured to limit any increase in the overall temperature of the liquid medium to less than 5° C. over the course of mixing. This aspect may also include, in some embodiments, any of the features discussed above.
In another aspect, the invention features an apparatus that includes a tank, a jet mixer having a nozzle disposed within the tank, and a delivery device configured to deliver a hydrocarbon-containing feedstock to the tank.
Some embodiments include one or more of the following features. The jet mixer can further include a motor, and the apparatus can further include a device configured to monitor the torque on the motor during mixing. The apparatus can also include a controller that adjusts the operation of the feedstock delivery device based on input from the torque-monitoring device.
All publications, patent applications, patents, and other references mentioned herein or attached hereto are incorporated by reference in their entirety for all that they contain.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing a sequence of steps for processing hydrocarbon-containing materials.
FIGS. 2 and 2A are diagrams illustrating jet flow exiting a nozzle.
FIG. 3 is a diagrammatic perspective view of a jet-flow agitator according to one embodiment. FIG. 3A is an enlarged perspective view of the impeller and jet tube of the jet-flow agitator of FIG. 3 . FIG. 3B is an enlarged perspective view of an alternate impeller.
FIG. 4 is a diagram of a suction chamber jet mixing nozzle according to one embodiment. FIG. 4A is a perspective view of a suction chamber jet mixing system according to another embodiment.
FIG. 5 is a diagrammatic perspective view of a jet mixing nozzle for a suction chamber jet mixing system according to another alternate embodiment.
FIG. 6 is a diagrammatic perspective view of a tank and a jet aeration type mixing system positioned in the tank, with the tank being shown as transparent to allow the jet mixer and associated piping to be seen. FIG. 6A is a perspective view of the jet mixer used in the jet aeration system of FIG. 6 . FIG. 6B is a diagrammatic perspective view of a similar system in which an air intake is provided.
FIG. 7 is a cross-sectional view of a jet aeration type mixer according to one embodiment.
FIG. 8 is a cross-sectional view of a jet aeration type mixer according to an alternate embodiment.
FIGS. 9-11 are diagrams illustrating alternative flow patterns in tanks containing different configurations of jet mixers.
FIG. 12 is a diagram illustrating the flow pattern that occurs in a tank during backflushing according to one embodiment.
FIG. 13 is a side view of a jet aeration type system according to another embodiment, showing a multi-level arrangement of nozzles in a tank.
FIGS. 14 and 14A are a diagrammatic top view and a perspective view, respectively, of a device that minimizes hold up along the walls of a tank during mixing.
FIGS. 15 and 16 are views of water jet devices that provide mixing while also minimizing hold up along the tank walls.
FIG. 17 is a cross-sectional view of a tank having a domed bottom and two jet mixers extending into the tank from above.
DETAILED DESCRIPTION
FIG. 1 shows a schematic diagram of a technique 100 for processing hydrocarbon-containing materials such as oil sands, oil shale, tar sands, and other materials that include hydrocarbons intermixed with solid components such as rock, sand, clay, silt, and/or solid organic material. These materials may be in their native form, or may have been previously treated, for example treated in situ with radiation as described below. In a first step of the sequence shown in FIG. 1 , the hydrocarbon-containing material 110 can be subjected to one or more optional mechanical processing steps 120 . The mechanical processing steps can include, for example, grinding, crushing, agitation, centrifugation, rotary cutting and/or chopping, shot-blasting, and various other mechanical processes that can reduce an average size of particles of material 110 , and initiate separation of the hydrocarbons from the remaining solid matter therein. In some embodiments, more than one mechanical processing step can be used. For example, multiple stages of grinding can be used to process material 110 . Alternatively, or in addition, a crushing process followed by a grinding process can be used to treat material 110 . Additional steps such as agitation and/or further crushing and/or grinding can also be used to further reduce the average size of particles of material 110 .
In a second step 130 of the sequence shown in FIG. 1 , the hydrocarbon-containing material 110 can be subjected to one or more optional cooling and/or temperature-cycling steps. In some embodiments, for example, material 110 can be cooled to a temperature at and/or below a boiling temperature of liquid nitrogen. More generally, the cooling and/or temperature-cycling in step 130 can include, for example, cooling to temperatures well below room temperature (e.g., cooling to 10° C. or less, 0° C. or less, −10° C. or less, −20° C. or less, −30° C. or less, −40° C. or less, −50° C. or less, −100° C. or less, −150° C. or less, −200 ° C. or less, or even lower temperatures). Multiple cooling stages can be performed, with varying intervals between each cooling stage to allow the temperature of material 110 to increase. The effect of cooling and/or temperature-cycling material 110 is to disrupt the physical and/or chemical structure of the material, promoting at least partial dissociation of the hydrocarbon components from the non-hydrocarbon components (e.g., solid non-hydrocarbon materials) in material 110 . Suitable methods and systems for cooling and/or temperature-cycling of material 110 are disclosed, for example, in U.S. Provisional Patent Application Ser. No. 61/081,709, filed on Jul. 17, 2008, and U.S. Ser. No. 12/502,629, filed Jul. 14, 2009, the entire contents of which are incorporated herein by reference.
In a third step 140 of the sequence of FIG. 1 , the hydrocarbon-containing material 110 can be exposed to charged particles or photons, such as photons having a wavelength between about 0.01 nm and 280 nm. In some embodiments, the photons can have a wavelength between, e.g., 100 nm to 280 nm or between 0.01 nm to 10 nm, or in some cases less than 0.01 nm. The charged particles interact with material 110 , causing further disassociation of the hydrocarbons therein from the non-hydrocarbon materials, and also causing various hydrocarbon chemical processes, including chain scission, bond-formation, and isomerization. These chemical processes convert long-chain hydrocarbons into shorter-chain hydrocarbons, many of which can eventually be extracted from material 110 as products and used directly for various applications. The chemical processes can also lead to conversion of various products into other products, some of which may be more desirable than others. For example, through bond-forming reactions, some short-chain hydrocarbons may be converted to medium-chain-length hydrocarbons, which can be more valuable products. As another example, isomerization can lead to the formation of straight-chain hydrocarbons from cyclic hydrocarbons. Such straight-chain hydrocarbons may be more valuable products than their cyclized counterparts.
By adjusting an average energy of the charged particles and/or an average current of the charged particles, the total amount of energy delivered or transferred to material 110 by the charged particles can be controlled. In some embodiments, for example, material 110 can be exposed to charged particles so that the energy transferred to material 110 (e.g., the energy dose applied to material 110 ) is 0.3 Mrad or more (e.g., 0.5 Mrad or more, 0.7 Mrad or more, 1.0 Mrad or more, 2.0 Mrad or more, 3.0 Mrad or more, 5.0 Mrad or more, 7.0 Mrad or more, 10.0 Mrad or more, 15.0 Mrad or more, 20.0 Mrad or more, 30.0 Mrad or more, 40.0 Mrad or more, 50.0 Mrad or more, 75.0 Mrad or more, 100.0 Mrad or more, 150.0 Mrad or more, 200.0 Mrad or more, 250.0 Mrad or more, or even 300.0 Mrad or more).
In general, electrons, ions, photons, and combinations of these can be used as the charged particles in step 140 to process material 110 . A wide variety of different types of ions can be used including, but not limited to, protons, hydride ions, oxygen ions, carbon ions, and nitrogen ions. These charged particles can be used under a variety of conditions; parameters such as particle currents, energy distributions, exposure times, and exposure sequences can be used to ensure that the desired extent of separation of the hydrocarbon components from the non-hydrocarbon components in material 110 , and the extent of the chemical conversion processes among the hydrocarbon components, is reached. Suitable systems and methods for exposing material 110 to charged particles are discussed, for example, in U.S. Ser. No. 12/417,699, filed Apr. 3, 2009, U.S. Ser. No. 12/486,436, filed Oct. 5, 2009, as well as the following U.S. Provisional Patent Applications: Ser. No. 61/049,406, filed on Apr. 30, 2008; Ser. No. 61/073,665, filed on Jun. 18, 2008; and Ser. No. 61/073,680, filed on Jun. 18, 2008. The entire contents of each of the foregoing applications is incorporated herein by reference. In particular, charged particle systems such as inductive linear accelerator (LINAC) systems can be used to deliver large doses of energy (e.g., doses of 50 Mrad or more) to material 110 .
In the final step of the processing sequence of FIG. 1 , the processed material 110 is subjected to a separation step 150 , which separates the hydrocarbon products 160 and the non-hydrocarbon products 170 . The separation step includes an extraction process that involves agitating the material 110 . For example, tar sands are processed using a hot water extraction process. After mining, the tar sands are transported to an extraction plant, where the hot water extraction process separates bitumen from sand, water and minerals. Hot water is added to the sand, and the resulting slurry is agitated. The combination of hot water and agitation releases bitumen from the oil sand in the form of droplets. Air bubbles attach to the bitumen droplets, causing the droplets to float to the top of the separation tank. The bitumen is then skimmed off and processed to remove residual water and solids. During this extraction process, agitation is performed using the jet mixing techniques discussed below.
A wide variety of other processing steps can optionally be used to further separate and refine the products. Exemplary processes include, but are not limited to, distillation, centrifugation and filtering.
The processing sequence shown in FIG. 1 is a flexible sequence, and can be modified as desired for particular materials 110 and/or to recover particular hydrocarbon products 160 . For example, the order of the various steps can be changed in FIG. 1 . Further, additional steps of the types shown, or other types of steps, can be included at any point within the sequence, as desired. For example, additional mechanical processing steps, cooling/temperature-cycling steps, particle beam exposure steps, and/or separation steps can be included at any point in the sequence. Further, other processing steps such as sonication, chemical processing, pyrolysis, oxidation and/or reduction, and radiation exposure can be included in the sequence shown in FIG. 1 prior to, during, and/or following any of the steps shown in FIG. 1 . Many processes suitable for inclusion in the sequence of FIG. 1 are discussed, for example, in PCT Publication No. WO 2008/073186 (e.g., throughout the Detailed Description section).
Suitable liquids that can be added to material 110 , e.g., during extraction, include, for example, water, various types of liquid hydrocarbons (e.g., hydrocarbon solvents), and other common organic and inorganic solvents.
Agitation
Jet Mixing Characteristics
Various types of mixing devices which may be used during hydrocarbon processing are described below. Other mixing devices having similar characteristics may be used. Suitable mixers have in common that they produce high velocity circulating flow, for example flow in a toroidal or elliptical pattern. Generally, preferred mixers exhibit a high bulk flow rate. Preferred mixers provide this mixing action with relatively low energy consumption. It is also preferred in some cases that the mixer produce relatively low shear and avoid heating of the liquid medium. As will be discussed in detail below, some preferred mixers draw the mixture through an inlet into a mixing element, which may include a rotor or impeller, and then expel the mixture from the mixing element through an outlet nozzle. This circulating action, and the high velocity of the jet exiting the nozzle, assist in dispersing material that is floating on the surface of the liquid or material that has settled to the bottom of the tank, depending on the orientation of the mixing element. Mixing elements can be positioned in different orientations to disperse both floating and settling material, and the orientation of the mixing elements can in some cases be adjustable.
For example, in some preferred mixing systems the velocity v o of the jet as meets the ambient fluid is from about 2 to 300 m/s, e.g., about 5 to 150 m/s or about 10 to 100 m/s. The power consumption of the mixing system may be about 20 to 1000 KW, e.g., 30 to 570 KW, 50 to 500 KW, or 150 to 250 KW for a 100,000 L tank. It is generally preferred that the power usage be low for cost-effectiveness.
Jet mixing involves the discharge of a submerged jet, or a number of submerged jets, of high velocity liquid into a fluid medium, in this case the mixture of feedstock and liquid medium. The jet of liquid penetrates the fluid medium, with its energy being dissipated by turbulence and some initial heat. This turbulence is associated with velocity gradients (fluid shear). The surrounding fluid is accelerated and entrained into the jet flow, with this secondary entrained flow increasing as the distance from the jet nozzle increases. The momentum of the secondary flow remains generally constant as the jet expands, as long as the flow does not hit a wall, floor or other obstacle. The longer the flow continues before it hits any obstacle, the more liquid is entrained into the secondary flow, increasing the bulk flow in the tank or vessel. When it encounters an obstacle, the secondary flow will lose momentum, more or less depending on the geometry of the tank, e.g., the angle at which the flow impinges on the obstacle. It is generally desirable to orient the jets and/or design the tank so that hydraulic losses to the tank walls are minimized. For example, it may be desirable for the tank to have an arcuate bottom (e.g., a domed headplate), and for the jet mixers to be oriented relatively close to the sidewalls, as shown in FIG. 17 . The tank bottom (lower head plate) may have any desired domed configuration, or may have an elliptical or conical geometry.
Jet mixing differs from most types of liquid/liquid and liquid/solid mixing in that the driving force is hydraulic rather than mechanical. Instead of shearing fluid and propelling it around the mixing vessel, as a mechanical agitator does, a jet mixer forces fluid through one or more nozzles within the tank, creating high-velocity jets that entrain other fluid. The result is shear (fluid against fluid) and circulation, which mix the tank contents efficiently.
Referring to FIG. 2 , the high velocity gradient between the core flow from a submerged jet and the surrounding fluid causes eddies. FIG. 2A illustrates the general characteristics of a submerged jet. As the submerged jet expands into the surrounding ambient environment the velocity profile flattens as the distance (x) from the nozzle increases. Also, the velocity gradient dv/dr changes with r (the distance from the centerline of the jet) at a given distance x, such that eddies are created which define the mixing zone (the conical expansion from the nozzle).
In an experimental study of a submerged jet in air (the results of which are applicable to any fluid, including water), Albertson et al. (“Diffusion of Submerged Jets,” Paper 2409, Amer. Soc. of Civil Engineers Transactions, Vol. 115:639-697, 1950, at p. 657) developed dimensionless relationships for v(x) r=0 /v o (centerline velocity), v(r) x /v(x) r−0 (velocity profile at a given x), Q x /Q o (flow entrainment), and E x /E o (energy change with x):
(1) Centerline velocity, v(x) r=0 /v o :
v
(
r
=
0
)
v
o
x
D
o
=
6.2
(2) velocity profile at any x, v(r) x /v(x) r=0 :
log
[
v
(
r
)
x
v
o
x
D
]
=
0.79
-
33
r
2
x
2
(3) Flow and energy at any x:
Q x Q o = 0.32 x D o ( 10.21 ) E x E o = 4.1 D o x ( 10.22 )
where:
v(r=0)=centerline velocity of submerged jet (m/s), v o =velocity of jet as it emerges from the nozzle (m/s), x=distance from nozzle (m), r=distance from centerline of jet (m), D o =diameter of nozzle (m), Q x =flow of fluid across any given plane at distance x from the nozzle (me/s), Q u =flow of fluid emerging from the nozzle (m3/s), E=energy flux of fluid across any given plane at distance x from the nozzle (m 3 /s), E o =energy flux of fluid emerging from the nozzle (m 3 /s).
(“Water Treatment Unit Processes: Physical and Chemical,” David W. Hendricks, CRC Press 2006, p. 411.)
Jet mixing is particularly cost-effective in large-volume (over 1,000 gal) and low-viscosity (under 1,000 cPs) applications. It is also generally advantageous that in most cases a jet mixer has no moving parts submerged, e.g., when a pump is used it is generally located outside the vessel.
One advantage of jet mixing is that the temperature of the ambient fluid (other than directly adjacent the exit of the nozzle, where there may be some localized heating) is increased only slightly if at all. For example, the temperature may be increased by less than 5° C., less than 1° C., or not to any measureable extent.
Jet-Flow Agitators
One type of jet-flow agitator is shown in FIGS. 3-3A . This type of mixer is available commercially, e.g., from IKA under the tradename ROTOTRON™. Referring to FIG. 3 , the mixer 200 includes a motor 202 , which rotates a drive shaft 204 . A mixing element 206 is mounted at the end of the drive shaft 204 . As shown in FIG. 3A , the mixing element 206 includes a shroud 208 and, within the shroud, an impeller 210 . As indicated by the arrows, when the impeller is rotated in its “forward” direction, the impeller 210 draws liquid in through the open upper end 212 of the shroud and forces the liquid out through the open lower end 214 . Liquid exiting end 214 is in the form of a high velocity stream or jet. If the direction of rotation of the impeller 210 is reversed, liquid can be drawn in through the lower end 214 and ejected through the upper end 212 . This can be used, for example, to suck in solids that are floating near or on the surface of the liquid in a tank or vessel. (It is noted that “upper” and “lower” refer to the orientation of the mixer in FIG. 3 ; the mixer may be oriented in a tank so that the upper end is below the lower end.)
The shroud 208 includes flared areas 216 and 218 adjacent its ends. These flared areas are believed to contribute to the generally toroidal flow that is observed with this type of mixer. The geometry of the shroud and impeller also concentrate the flow into a high velocity stream using relatively low power consumption.
Preferably, the clearance between the shroud 208 and the impeller 210 is sufficient so as to avoid excessive milling of the material as it passes through the shroud. For example, the clearance may be at least 10 times the average particle size of the solids in the mixture, preferably at least 100 times.
In some implementations, the shaft 204 is configured to allow gas delivery through the shaft. For example, the shaft 204 may include a bore (not shown) through which gas is delivered, and one or more orifices through which gas exits into the mixture. The orifices may be within the shroud 208 , to enhance mixing, and/or at other locations along the length of the shaft 204 .
The impeller 210 may have any desired geometry that will draw liquid through the shroud at a high velocity. The impeller is preferably a marine impeller, as shown in FIG. 3A , but may have a different design, for example, a Rushton impeller as shown in FIG. 3B , or a modified Rushton impeller, e.g., tilted so as to provide some axial flow.
In order to generate the high velocity flow through the shroud, the motor 202 is preferably a high speed, high torque motor, e.g., capable of operating at 500 to 20,000 RPM, e.g., 3,000 to 10,000 RPM. However, the larger the mixer (e.g., the larger the shroud and/or the larger the motor) the lower the rotational speed can be. Thus, if a large mixer is used, such as a 5 hp, 10 hp, 20 hp, or 30 hp or greater, the motor may be designed to operate at lower rotational speeds, e.g., less than 2000 RPM, less than 1500 RPM, or even 500 RPM or less. For example, a mixer sized to mix a 10,000-20,000 liter tank may operate at speeds of 900 to 1,200 RPM. The torque of the motor is preferably self-adjusting, to maintain a relatively constant impeller speed as the mixing conditions change over time.
Advantageously, the mixer can be oriented at any desired angle or location in the tank, to direct the jet flow in a desired direction. Moreover, as discussed above, depending on the direction of rotation of the impeller the mixer can be used to draw fluid from either end of the shroud.
In some implementations, two or more jet mixers are positioned in the vessel, with one or more being configured to jet fluid upward (“up pump”) and one or more being configured to jet fluid downward (“down pump”). In some cases, an up pumping mixer will be positioned adjacent a down pumping mixer, to enhance the turbulent flow created by the mixers. If desired, one or more mixers may be switched between upward flow and downward flow during processing. It may be advantageous to switch all or most of the mixers to up pumping mode during initial dispersion of the feedstock in the liquid medium, as up pumping creates significant turbulence at the surface.
Suction Chamber Jet Mixers
Another type of jet mixer includes a primary nozzle that delivers a pressurized fluid from a pump, a suction inlet adjacent the primary nozzle through which ambient fluid is drawn by the pressure drop between the primary nozzle and the wider inlet, and a suction chamber extending between the suction inlet and a secondary nozzle. A jet of high velocity fluid exits the secondary nozzle.
An example of this type of mixer is shown in FIG. 4 . As shown, in mixer 600 pressurized liquid from a pump (not shown) flows through an inlet passage 602 and exits through a primary nozzle 603 . Ambient liquid is drawn through a suction inlet 604 into suction chamber 606 by the pressure drop caused by the flow of pressurized liquid. The combined flow exits from the suction chamber into the ambient liquid at high velocity through secondary nozzle 608 . Mixing occurs both in the suction chamber and in the ambient liquid due to the jet action of the exiting jet of liquid.
A mixing system that operates according to a similar principle is shown in FIG. 4A . Mixers embodying this design are commercially available from ITT Water and Wastewater, under the tradename Flygt™ jet mixers. In system 618 , pump 620 generates a primary flow that is delivered to the tank (not shown) through a suction nozzle system 622 . The suction nozzle system 622 includes a primary nozzle 624 which functions in a manner similar to primary nozzle 603 described above, causing ambient fluid to be drawn into the adjacent open end 626 of ejector tube 628 due to the pressure drop induced by the fluid exiting the primary nozzle. The combined flow then exits the other end 630 of ejector tube 628 , which functions as a secondary nozzle, as a high velocity jet.
The nozzle shown in FIG. 5 , referred to as an eductor nozzle, operates under a similar principle. A nozzle embodying this design is commercially available under the tradename TeeJet®. As shown, in nozzle 700 pressurized liquid flows in through an inlet 702 and exits a primary nozzle 704 , drawing ambient fluid in to the open end 706 of a diffuser 708 . The combined flow exits the opposite open end 710 of the diffuser at a circulation flow rate A+B that is the sum of the inlet flow rate A and the flow rate B of the entrained ambient fluid.
Jet Aeration Type Mixers
Another type of jet mixing system that can be utilized is referred to in the wastewater industry as “jet aeration mixing.” In the wastewater industry, these mixers are typically used to deliver a jet of a pressurized air and liquid mixture, to provide aeration. However, in the present application in some cases the jet aeration type mixers are utilized without pressurized gas, as will be discussed below. The principles of operation of jet aeration mixers will be initially described in the context of their use with pressurized gas, for clarity.
An eddy jet mixer, such as the mixer 800 shown in FIGS. 6-6B , includes multiple jets 802 mounted in a radial pattern on a central hub 804 . The radial pattern of the jets uniformly distributes mixing energy throughout the tank. The eddy jet mixer may be centrally positioned in a tank, as shown to provide toroidal flow about the center axis of the tank. The eddy jet mixer may be mounted on piping 806 , which supplies high velocity liquid to the eddy jet mixer. In the embodiment shown in FIG. 6B , air is also supplied to the eddy jet mixer through piping 812 . The high velocity liquid is delivered by a pump 808 which is positioned outside of the tank and which draws liquid in through an inlet 810 in the side wall of the tank.
FIGS. 7 and 8 show two types of nozzle configurations that are designed to mix a gas and a liquid stream and eject a high velocity jet. These nozzles are configured somewhat differently from the eddy jet mixer shown in FIGS. 6 and 6A but function in a similar manner. In the system 900 shown in FIG. 7 , a primary or motive fluid is directed through a liquid line 902 to inner nozzles 904 through which the liquid travels at high velocity into a mixing area 906 . A second fluid, e.g., a gas, such as compressed air, nitrogen or carbon dioxide, or a liquid, enters the mixing area through a second line 908 and entrained in the motive fluid entering the mixing area 906 through the inner nozzles. In some instances the second fluid is nitrogen or carbon dioxide so as to reduce oxidation of the enzyme. The combined flow from the two lines is jetted into the mixing tank through the outer nozzles 910 . If the second fluid is a gas, tiny bubbles are entrained in the liquid in the mixture. Liquid is supplied to the liquid line 902 by a pump. Gas, if it is used, is provided by compressors. If a liquid is used as the second fluid, it can have the same velocity as the liquid entering through the liquid line 902 , or a different velocity.
FIG. 8 shows an alternate nozzle design 1000 , in which outer nozzles 1010 (of which only one is shown) are positioned along the length of an elongated member 1011 that includes a liquid line 1002 that is positioned parallel to a second line 1008 . Each nozzle includes a single outer nozzle 1010 and a single inner nozzle 1004 . Mixing of the motive liquid with the second fluid proceeds in the same manner as in the system 900 described above.
FIGS. 9 and 10 illustrate examples of jet aeration type mixing systems in which nozzles are positioned along the length of an elongated member. In the example shown in FIG. 9 , the elongated member 1102 is positioned along the diameter of the tank 1104 , and the nozzles 1106 extend in opposite directions from the nozzle to produce the indicated flow pattern which includes two areas of generally elliptical flow, one on either side of the central elongated member. In the example shown in FIG. 10 , the tank 1204 is generally rectangular in cross section, and the elongated member 1202 extends along one side wall 1207 of the tank. In this case, the nozzles 1206 all face in the same direction, towards the opposite side wall 1209 . This produces the flow pattern shown, in which flow in the tank is generally elliptical about a major axis extending generally centrally along the length of the tank. In the embodiment shown in FIG. 10 , the nozzles may be canted towards the tank floor, e.g., at an angle of from about 15 to 30 degrees from the horizontal.
In another embodiment, shown in FIG. 11 , the nozzles 1302 , 1304 , and suction inlet 1306 are arranged to cause the contents of the tank to both revolve and rotate in a toroidal, rolling donut configuration around a central vertical axis of the tank. Flow around the surface of the toroid is drawn down the tank center, along the floor, up the walls and back to the center, creating a rolling helix pattern, which sweeps the center and prevents solids from settling. The toroidal pattern is also effective in moving floating solids to the tank center where they are pulled to the bottom and become homogenous with the tank contents. The result is a continuous helical flow pattern, which minimizes tank dead spots.
Backflushing
In some instances, the jet nozzles described herein can become plugged, which may cause efficiency and cost effectiveness to be reduced. Plugging of the nozzles may be removed by reversing flow of the motive liquid through the nozzle. For example, in the system shown in FIG. 12 , this is accomplished by closing a valve 1402 between the pump 1404 and the liquid line 1406 flowing to the nozzles 1408 , and activating a secondary pump 1410 . Secondary pump 1410 draws fluid in through the nozzles. The fluid then travels up through vertical pipe 1412 due to valve 1402 being closed. The fluid exits the vertical pipe 1412 at its outlet 1414 for recirculation through the tank.
Mixing in Transit/Portable Mixers
In some cases processing can take place in part or entirely during transportation of the mixture, e.g., between a first processing plant for treating the feedstock and a second processing plant for production of a final product. In this case, mixing can be conducted using a jet mixer designed for rail car or other portable use. The mixer can be operated using a control system that is external to the tank, which may include for example a motor and a controller configured to control the operation of the mixer. Venting (not shown) may also be provided.
Minimizing Hold Up on Tank Walls
In some situations, in particular at solids levels approaching a theoretical or practical limit, material may accumulate along the side wall and/or bottom wall of the tank during mixing. This phenomenon, referred to as “hold up,” is undesirable as it can result in inadequate mixing. Several approaches can be taken to minimize hold up and ensure good mixing throughout the tank.
For example, in addition to the jet mixing device(s), the tank can be outfitted with a scraping device, for example a device having a blade that scrapes the side of the tank in a “squeegee” manner. Such devices are well known, for example in the dairy industry. Suitable agitators include the side and bottom sweep agitators and scraper blade agitators manufactured by Walker Engineered Products, New Lisbon, Wis. As shown in FIG. 14 , a side and bottom sweep agitator 1800 may include a central elongated member 1802 , mounted to rotate about the axis of the tank. Side wall scraper blades 1804 are mounted at each end of the elongated member 1802 and are disposed at an angle with respect to the elongated member. In the embodiment shown, a pair of bottom wall scraper blades 1806 are mounted at an intermediate point on the elongated member 1802 , to scrape up any material accumulating on the tank bottom. These scrapers may be omitted if material is not accumulating on the tank bottom. As shown in FIG. 14A , the scraper blades 1804 may be in the form of a plurality of scraper elements positioned along the side wall. In other embodiments, the scraper blades are continuous, or may have any other desired geometry.
In other embodiments, the jet mixer itself is configured so as to minimize hold up. For example, the jet mixer may include one or more movable heads and/or flexible portions that move during mixing. For example, the jet mixer may include an elongated rotatable member having a plurality of jet nozzles along its length. The elongated member may be planar, as shown in FIG. 15 , or have a non-planar shape, e.g., it may conform to the shape of the tank walls as shown in FIG. 16 .
Referring to FIG. 15 , the jet mixer nozzles may be positioned on a rotating elongated member 1900 that is driven by a motor 1902 and shaft 1904 . Water or other fluid is pumped through passageways in the rotating member, e.g., by a pump impeller 1906 , and exits as a plurality of jets through jet orifices 1908 while the member 1900 rotates. To reduce hold up on the tank side walls, orifices 1910 may be provided at the ends of the member 1900 .
In the embodiment shown in FIG. 16 , to conform to the particular shape of the tank 2000 the elongated member includes horizontally extending arms 2002 , downwardly inclined portions 2004 , outwardly and upwardly inclined portions 2006 , and vertically extending portions 2008 . Fluid is pumped through passageways within the elongated member to a plurality of jet orifices 38 , through which jets are emitted while the elongated member is rotated.
In both of the embodiments shown in FIGS. 15 and 16 , the jets provide mixing while also washing down the side walls of the tank.
In some implementations, combinations of the embodiments described above may be used. For example, combinations of planar and non-planar rotating or oscillating elongated members may be used. The moving nozzle arrangements described above can be used in combination with each other and/or in combination with scrapers. A plurality of moving nozzle arrangements can be used together, for example two or more of the rotating members shown in FIG. 15 can be stacked vertically in the tank. When multiple rotating members are used, they can be configured to rotate in the same direction or in opposite directions, and at the same speed or different speeds.
Physical Treatment of Feedstock
In some implementations, the feedstock is physically treated, e.g., to change its molecular structure. Physical treatment processes can include one or more of any of those described herein, such as mechanical treatment, chemical treatment, irradiation, sonication, oxidation, pyrolysis or steam explosion. Treatment methods can be used in combinations of two, three, four, or even all of these technologies (in any order). When more than one treatment method is used, the methods can be applied at the same time or at different times. Other processes that change a molecular structure of a feedstock may also be used, alone or in combination with the processes disclosed herein.
Mechanical Treatments
In some cases, methods can include a mechanical treatment. Mechanical treatments include, for example, cutting, milling, pressing, grinding, shearing and chopping. Milling may include, for example, ball milling, hammer milling, rotor/stator dry or wet milling, or other types of milling. Other mechanical treatments include, e.g., stone grinding, cracking, mechanical ripping or tearing, pin grinding or air attrition milling.
In some implementations, the feedstock material can first be physically treated by one or more of the other physical treatment methods, e.g., chemical treatment, radiation, sonication, oxidation, pyrolysis or steam explosion, and then mechanically treated. This sequence can be advantageous since materials treated by one or more of the other treatments, e.g., irradiation or pyrolysis, tend to be more brittle and, therefore, it may be easier to further change the molecular structure of the material by mechanical treatment.
Feed preparation systems can be configured to produce streams with specific characteristics such as, for example, specific maximum sizes or specific surface areas.
Radiation Treatment
Irradiation can reduce the molecular weight and/or crystallinity of feedstock. In some embodiments, energy deposited in a material that releases an electron from its atomic orbital is used to irradiate the materials. The radiation may be provided by 1) heavy charged particles, such as alpha particles or protons, 2) electrons, produced, for example, in beta decay or electron beam accelerators, or 3) electromagnetic radiation, for example, gamma rays, x rays, or ultraviolet rays. In one approach, radiation produced by radioactive substances can be used to irradiate the feedstock. In some embodiments, any combination in any order or concurrently of (1) through (3) may be utilized. In another approach, electromagnetic radiation (e.g., produced using electron beam emitters) can be used to irradiate the feedstock. The doses applied depend on the desired effect and the particular feedstock. For example, high doses of radiation can break chemical bonds within feedstock components. In some instances when chain scission is desirable and/or polymer chain functionalization is desirable, particles heavier than electrons, such as protons, helium nuclei, argon ions, silicon ions, neon ions, carbon ions, phosphorus ions, oxygen ions or nitrogen ions can be utilized. When ring-opening chain scission is desired, positively charged particles can be utilized for their Lewis acid properties for enhanced ring-opening chain scission. For example, when maximum oxidation is desired, oxygen ions can be utilized, and when maximum nitration is desired, nitrogen ions can be utilized.
Ionizing Radiation
Each form of radiation ionizes the carbon-containing material via particular interactions, as determined by the energy of the radiation. Heavy charged particles primarily ionize matter via Coulomb scattering; furthermore, these interactions produce energetic electrons that may further ionize matter. Alpha particles are identical to the nucleus of a helium atom and are produced by the alpha decay of various radioactive nuclei, such as isotopes of bismuth, polonium, astatine, radon, francium, radium, several actinides, such as actinium, thorium, uranium, neptunium, curium, californium, americium, and plutonium.
When particles are utilized, they can be neutral (uncharged), positively charged or negatively charged. When charged, the charged particles can bear a single positive or negative charge, or multiple charges, e.g., one, two, three or even four or more charges. In instances in which chain scission is desired, positively charged particles may be desirable, in part due to their acidic nature. When particles are utilized, the particles can have the mass of a resting electron, or greater, e.g., 500, 1000, 1500, 2000, 10,000 or even 100,000 times the mass of a resting electron. For example, the particles can have a mass of from about 1 atomic unit to about 150 atomic units, e.g., from about 1 atomic unit to about 50 atomic units, or from about 1 to about 25, e.g., 1, 2, 3, 4, 5, 10, 12 or 15 amu. Accelerators used to accelerate the particles can be electrostatic DC, electrodynamic DC, RF linear, magnetic induction linear or continuous wave. For example, cyclotron type accelerators are available from IBA, Belgium, such as the Rhodotron® system, while DC type accelerators are available from RDI, now IBA Industrial, such as the Dynamitron®. Ions and ion accelerators are discussed in Introductory Nuclear Physics, Kenneth S. Krane, John Wiley & Sons, Inc. (1988), Krsto Prelec, FIZIKA B 6 (1997) 4, 177-206, Chu, William T., “Overview of Light-Ion Beam Therapy” Columbus-Ohio, ICRU-IAEA Meeting, 18-20 Mar. 2006, Iwata, Y. et al., “Alternating-Phase-Focused IH-DTL for Heavy-Ion Medical Accelerators” Proceedings of EPAC 2006, Edinburgh, Scotland and Leaner, C. M. et al., “Status of the Superconducting ECR Ion Source Venus” Proceedings of EPAC 2000, Vienna, Austria.
Gamma radiation has the advantage of a significant penetration depth into a variety of materials. Sources of gamma rays include radioactive nuclei, such as isotopes of cobalt, calcium, technicium, chromium, gallium, indium, iodine, iron, krypton, samarium, selenium, sodium, thalium, and xenon.
Sources of x rays include electron beam collision with metal targets, such as tungsten or molybdenum or alloys, or compact light sources, such as those produced commercially by Lyncean.
Sources for ultraviolet radiation include deuterium or cadmium lamps.
Sources for infrared radiation include sapphire, zinc, or selenide window ceramic lamps.
Sources for microwaves include klystrons, Slevin type RF sources, or atom beam sources that employ hydrogen, oxygen, or nitrogen gases.
In some embodiments, a beam of electrons is used as the radiation source. A beam of electrons has the advantages of high dose rates (e.g., 1, 5, or even 10 Mrad per second), high throughput, less containment, and less confinement equipment. Electrons can also be more efficient at causing chain scission. In addition, electrons having energies of 4-10 MeV can have a penetration depth of 5 to 30 mm or more, such as 40 mm.
Electron beams can be generated, e.g., by electrostatic generators, cascade generators, transformer generators, low energy accelerators with a scanning system, low energy accelerators with a linear cathode, linear accelerators, and pulsed accelerators. Electrons as an ionizing radiation source can be useful, e.g., for relatively thin piles of materials, e.g., less than 0.5 inch, e.g., less than 0.4 inch, 0.3 inch, 0.2 inch, or less than 0.1 inch. In some embodiments, the energy of each electron of the electron beam is from about 0.3 MeV to about 2.0 MeV (million electron volts), e.g., from about 0.5 MeV to about 1.5 MeV, or from about 0.7 MeV to about 1.25 MeV.
Electron beam irradiation devices may be procured commercially from Ion Beam Applications, Louvain-la-Neuve, Belgium or the Titan Corporation, San Diego, Calif. Typical electron energies can be 1 MeV, 2 MeV, 4.5 MeV, 7.5 MeV, or 10 MeV. Typical electron beam irradiation device power can be 1 kW, 5 kW, 10 kW, 20 kW, 50 kW, 100 kW, 250 kW, or 500 kW. The level of depolymerization of the feedstock depends on the electron energy used and the dose applied, while exposure time depends on the power and dose. Typical doses may take values of 1 kGy, 5 kGy, 10 kGy, 20 kGy, 50 kGy, 100 kGy, or 200 kGy.
Ion Particle Beams
Particles heavier than electrons can be utilized to irradiate hydrocarbon-containing materials. For example, protons, helium nuclei, argon ions, silicon ions, neon ions carbon ions, phosphorus ions, oxygen ions or nitrogen ions can be utilized. In some embodiments, particles heavier than electrons can induce higher amounts of chain scission (relative to lighter particles). In some instances, positively charged particles can induce higher amounts of chain scission than negatively charged particles due to their acidity.
Heavier particle beams can be generated, e.g., using linear accelerators or cyclotrons. In some embodiments, the energy of each particle of the beam is from about 1.0 MeV/atomic unit to about 6,000 MeV/atomic unit, e.g., from about 3 MeV/atomic unit to about 4,800 MeV/atomic unit, or from about 10 MeV/atomic unit to about 1,000 MeV/atomic unit.
In certain embodiments, ion beams can include more than one type of ion. For example, ion beams can include mixtures of two or more (e.g., three, four or more) different types of ions. Exemplary mixtures can include carbon ions and protons, carbon ions and oxygen ions, nitrogen ions and protons, and iron ions and protons. More generally, mixtures of any of the ions discussed above (or any other ions) can be used to form irradiating ion beams. In particular, mixtures of relatively light and relatively heavier ions can be used in a single ion beam.
In some embodiments, ion beams for irradiating materials include positively-charged ions. The positively charged ions can include, for example, positively charged hydrogen ions (e.g., protons), noble gas ions (e.g., helium, neon, argon), carbon ions, nitrogen ions, oxygen ions, silicon atoms, phosphorus ions, and metal ions such as sodium ions, calcium ions, and/or iron ions. Without wishing to be bound by any theory, it is believed that such positively-charged ions behave chemically as Lewis acid moieties when exposed to materials, initiating and sustaining cationic ring-opening chain scission reactions in an oxidative environment.
In certain embodiments, ion beams for irradiating materials include negatively-charged ions. Negatively charged ions can include, for example, negatively charged hydrogen ions (e.g., hydride ions), and negatively charged ions of various relatively electronegative nuclei (e.g., oxygen ions, nitrogen ions, carbon ions, silicon ions, and phosphorus ions). Without wishing to be bound by any theory, it is believed that such negatively-charged ions behave chemically as Lewis base moieties when exposed to materials, causing anionic ring-opening chain scission reactions in a reducing environment.
In some embodiments, beams for irradiating materials can include neutral atoms. For example, any one or more of hydrogen atoms, helium atoms, carbon atoms, nitrogen atoms, oxygen atoms, neon atoms, silicon atoms, phosphorus atoms, argon atoms, and iron atoms can be included in beams that are used for irradiation of hydrocarbon-containing materials. In general, mixtures of any two or more of the above types of atoms (e.g., three or more, four or more, or even more) can be present in the beams.
In certain embodiments, ion beams used to irradiate materials include singly-charged ions such as one or more of H + , H − , He + , Ne + , Ar + , C + , C − , O + , O − , N + , N − , Si + , Si − , P + , P − , Na + , Ca + , and Fe + . In some embodiments, ion beams can include multiply-charged ions such as one or more of C 2+ , C 3+ , C 4+ , N 3+ , N 5+ , N 3− , O 2+ , O 2− , O 2 2− , Si 2+ , Si 4+ , Si 2− , and Si 4− . In general, the ion beams can also include more complex polynuclear ions that bear multiple positive or negative charges. In certain embodiments, by virtue of the structure of the polynuclear ion, the positive or negative charges can be effectively distributed over substantially the entire structure of the ions. In some embodiments, the positive or negative charges can be somewhat localized over portions of the structure of the ions.
Electromagnetic Radiation
In embodiments in which the irradiating is performed with electromagnetic radiation, the electromagnetic radiation can have, e.g., energy per photon (in electron volts) of greater than 10 2 eV, e.g., greater than 10 3 , 10 4 , 10 5 , 10 6 , or even greater than 10 7 eV. In some embodiments, the electromagnetic radiation has energy per photon of between 10 4 and 10 7 , e.g., between 10 5 and 10 6 eV. The electromagnetic radiation can have a frequency of, e.g., greater than 10 16 H z , greater than 10 17 Hz, 10 18 , 10 19 , 10 20 , or even greater than 10 21 Hz. In some embodiments, the electromagnetic radiation has a frequency of between 10 18 and 10 22 Hz, e.g., between 10 19 to 10 21 Hz.
Doses
In some embodiments, the irradiating (with any radiation source or a combination of sources) is performed until the material receives a dose of at least 0.25 Mrad, e.g., at least 1.0 Mrad, at least 2.5 Mrad, at least 5.0 Mrad, or at least 10.0 Mrad. In some embodiments, the irradiating is performed until the material receives a dose of between 1.0 Mrad and 6.0 Mrad, e.g., between 1.5 Mrad and 4.0 Mrad.
In some embodiments, the irradiating is performed at a dose rate of between 5.0 and 1500.0 kilorads/hour, e.g., between 10.0 and 750.0 kilorads/hour or between 50.0 and 350.0 kilorads/hours.
In some embodiments, two or more radiation sources are used, such as two or more ionizing radiations. For example, samples can be treated, in any order, with a beam of electrons, followed by gamma radiation and UV light having wavelengths from about 100 nm to about 280 nm. In some embodiments, samples are treated with three ionizing radiation sources, such as a beam of electrons, gamma radiation, and energetic UV light.
Sonication, Pyrolysis and Oxidation
In addition to radiation treatment, the feedstock may be treated with any one or more of sonication, pyrolysis and oxidation. These treatment processes are described in U.S. Ser. No. 12/417,840, the disclosure of which is incorporated by reference herein.
Other Processes
Any of the processes of this paragraph can be used alone without any of the processes described herein, or in combination with any of the processes described herein (in any order): steam explosion, acid treatment (including concentrated and dilute acid treatment with mineral acids, such as sulfuric acid, hydrochloric acid and organic acids, such as trifluoroacetic acid), base treatment (e.g., treatment with lime or sodium hydroxide), UV treatment, screw extrusion treatment (see, e.g., U.S. Patent Application Ser. No. 61/073,530, filed Nov. 18, 2008, solvent treatment (e.g., treatment with ionic liquids) and freeze milling (see, e.g., U.S. patent application Ser. No. 61/081,709).
OTHER EMBODIMENTS
A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure.
For example, the jet mixers described herein can be used in any desired combination, and/or in combination with other types of mixers.
The jet mixer(s) may be mounted in any desired position within the tank. With regard to shaft-mounted jet mixers, the shaft may be collinear with the center axis of the tank or may be offset therefrom. For example, if desired the tank may be provided with a centrally mounted mixer of a different type, e.g., a marine impeller or Rushton impeller, and a jet mixer may be mounted in another area of the tank either offset from the center axis or on the center axis. In the latter case one mixer can extend from the top of the tank while the other extends upward from the floor of the tank. Moreover, as shown in FIG. 13 , two or more jet mixers can be mounted in a multi-level arrangement at different heights within the tank.
In any of the jet mixing systems described herein, the flow of fluid (liquid and/or gas) through the jet mixer can be continuous or pulsed, or a combination of periods of continuous flow with intervals of pulsed flow. When the flow is pulsed, pulsing can be regular or irregular. In the latter case, the motor that drives the fluid flow can be programmed, for example to provide pulsed flow at intervals to prevent mixing from becoming “stuck.” The frequency of pulsed flow can be, for example, from about 0.5 Hz to about 10 Hz, e.g., about 0.5 Hz, 0.75 Hz, 1.0 Hz, 2.0 Hz, 5 Hz, or 10 Hz. Pulsed flow can be provided by turning the motor on and off, and/or by providing a flow diverter that interrupts flow of the fluid.
While tanks have been referred to herein, jet mixing may be used in any type of vessel or container, including lagoons, pools, ponds and the like. If the container in which mixing takes place is an in-ground structure such as a lagoon, it may be lined. The container may be covered, e.g., if it is outdoors, or uncovered.
While hydrocarbon-containing feedstocks have been described herein, other feedstocks and mixtures of hydrocarbon-containing feedstocks with other feedstocks may be used. For example, some implementations may utilize mixtures of hydrocarbon-containing feedstocks with biomass feedstocks such as those disclosed in U.S. Provisional Application No. 61/218,832, filed Jun. 19, 2009, the full disclosure of which is incorporated by reference herein.
Accordingly, other embodiments are within the scope of the following claims. | Hydrocarbon-containing feedstocks are processed to produce useful intermediates or products, such as fuels. For example, systems are described that can process a petroleum-containing feedstock, such as oil sands, oil shale, tar sands, and other naturally-occurring and synthetic materials that include both hydrocarbon components and solid matter, to obtain a useful intermediate or product. | 4 |
FIELD OF THE INVENTION
This invention relates to bathing enclosures. More particularly, it pertains to bathing enclosures that can be divided into portions and then subsequently reassembled.
BACKGROUND OF THE INVENTION
The term "bathing enclosure" encompasses a wide variety of types of plumbing fixtures such as bathtubs, showers, whirlpools, spas, saunas, and environmental enclosures. In many modern designs these bathing enclosures are molded from fiberglass or other materials in one-piece. This yields significant production efficiencies and minimizes installation costs.
A disadvantage of one-piece units is their size. There sometimes is not sufficient space to introduce such units into existing buildings. This is a particular problem when it is desired to remodel a bathroom in an old building where the size of the doorways and halls are already fixed. Removing building walls and widening doorways to remodel a bathroom can significantly increase the cost of the project.
Some bathing enclosures are designed so as to be suitable to be cast as a single piece and then cut into two or more pieces. The pieces are then transported through small entranceways and reassembled at installation sites.
One such "knock down" type bathing enclosure is that disclosed in U.S. Pat. No. 4,901,380. That enclosure has a horizontally extending joining strip attached to the outside of the enclosure. The strip adheres to the enclosure outer wall and has an outer tubular bulge. The wall (with joining strip thereon) is cut into two pieces along a horizontal plane that also passes through the tubular bulge. A plurality of locator lugs are then inserted into an internal slot formed in the bulge. Guided into proper alignment by the lugs, the cut portions are then fastened together using clamps.
The 4,901,380 system previously had the horizontally extending joining strips extend around corners of the enclosure. However, as corners on such enclosures became more numerous and more closely spaced (e.g. a corner at the intersection of the side wall with a small frontal frame for the tub opening; a corner near a soap dish recess), use of this system became more difficult.
Thus, it can be seen that a need exists for an improved knock down type bathing enclosure.
SUMMARY OF THE INVENTION
The invention provides a bathing enclosure of the type having a multi-piece plumbing fixture wall structure with a first portion and a second portion. The first portion has walls with edges which can be substantially aligned with opposed edges of walls of the second portion so as to define a generally horizontal seam. Means are provided for restricting vertical movement of the wall portions relative to one another.
The improvement relates to having a first and second web. The webs are on an external side of the wall structure and each has a vertically extending rib and an enlarged vertically extending head on the rib.
One of the webs is affixed to the first wall structure portion and the other of the webs is affixed to the second wall structure portion. The webs are both affixed adjacent the seam such that the ribs and heads are vertically aligned with one another. Together they form a vertically extending alignment bar. A clip is positioned around the outside of both ribs so as to restrict horizontal movement of the heads relative to one another.
In a preferred embodiment, the clip is in the form of a C-shaped tube. The clip has a hollow central section that is suitable to house portions of the aligned heads of the webs, and feet that interfit with necks on the ribs. The lower end of the feet, neck, and/or hollow can be tapered so that the clip widens at the bottom to more readily accept the alignment bar. Preferably, means are provided between the clip and the webs to inhibit downward movement of the C-shaped clip on the webs past a selected point.
The webs may be positioned at a generally flat portion of the enclosure wall, albeit very near a corner of the enclosure. However, they can instead be provided on a curved wall surface (and thus used directly at the corner).
In an especially preferred form, the webs are used in combination with the U.S. Pat. No. 4,901,380 system. Instead of having the U.S. Pat. No. 4,901,380 clamping system extend all the way around the tub, the prior system is only used on very long straight areas of the tub (with breaks there between). The clips and webs are used in these breaks. The combination of the prior clamping system with the webs and clips of the present invention is highly advantageous.
One object of the present invention is therefore to provide a bathing enclosure that can be cut and reassembled without loss of height of the bathing enclosure.
It is another object of the invention to provide a system for reassembling cut portions of a bathing enclosure that permits easy alignment of the upper and lower portions.
It is yet another object of the invention to provide a system of this type which can be used with enclosures having tight corners.
The foregoing and other objects and advantages of the invention will be evident from the following description. In the description, reference should be made to the accompanying drawings which form a part hereof. Such embodiments do not necessarily represent the full scope of the invention. Reference should therefore also be made to the claims herein for interpreting the full scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top perspective view of bathing enclosure in accordance with the present invention;
FIG. 2 is an enlarged perspective view taken from the interior of the enclosure of a part of the enclosure that incorporates the U.S. Pat. No. 4,901,380 system;
FIG. 3 is a perspective view of the preferred web shown vertically affixed to an outer wall of a bathing enclosure, albeit before the enclosure and web are cut in two;
FIG. 4 is a perspective view similar to FIG. 3, except that the web and bathing enclosure have been cut in two and a C-clip has been positioned nearby;
FIG. 5 is a view similar to FIG. 4, but with the C-clip shown assembled on the aligned webs after the bathing enclosure sections have been placed on top of one another. This is a position that can be used for compact shipment of the enclosure, or if a sealant is used represents the installed position;
FIG. 6 is a sectional view taken on line 6--6 of FIG. 5; and
FIG. 7 is a perspective view of a portion of a second bathing enclosure showing how multiple webs and clips can be used.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In a preferred embodiment of a present invention there is provided a bathing enclosure 10 which is defined by three side walls, a tub, and an apron. Preferably the walls are an acrylic-faced fiberglass reinforced polyester resin. The enclosure is split into an upper portion 11 and a lower portion 12. Vertical edges 13, 14 of these portions are aligned so as to define a seam 15 that runs substantially horizontally around the tub enclosure.
As best seen in FIG. 2, there is provided a first joining strip 17 and a second joining strip 18. The joining strips are attached on the external side of the wall structures and have inner attachment surfaces 19 for abutment, outer bulges 20, and outer clamp abutment surfaces 21 on the bulges. Slots 22 are formed so as to run along the strips. U.S. Pat. No. 4,901,380 is hereby incorporated by reference as if fully set forth herein. This patent describes in greater detail the FIG. 2 joining strip/locater lug system.
Joining strips 17 and 18 are preferably made of an acrylic-based polymer CYRO-XT375 from Cyro Industries. The precursor of strips 17 and 18 is fixed to the precursor of walls 11 and 12 using an adhesive such as a fiberglass reinforced polyester resin. The wall and joining strip are then each cut into two pieces along seam 15 (which is defined by the cut). The slots 22 face each other and define a tubular inner hollow along the seam.
Locator members 24 are positional inside the hollow so as to assist in alignment. The locator members can be an inch or two in width, or if desired a single locator member can extend for the full length of each slot. Moreover, the locator itself need not be hollow.
As shown in FIG. 1, clamps 25 can fasten together the enclosure portions 11 and 12 by abutting against the clamp abutment surfaces 21. The clamps assist in creating a water tight seal, but if desired a silicone or other sealant can also be used at the seam.
In accordance with the present invention there is also provided a web structure 31. The web is preferably made of CYRO-XT375 and attached to the tub exterior with fiberglass reinforced polyester. After the web has been attached in substantially vertical fashion to a tub enclosure that has been molded as a single piece, and after joining strips 17, 18 have been affixed to each side, the enclosure can be cut in two along a substantially horizontal seam. The web will end up in two pieces 32 and 33 (see FIG. 4). Note also that the web could instead be formed integrally with the enclosure.
There is also provided a C-shaped clip 36 which has a central hollow 37 and legs 38. When the tub wall portions 11 and 12 are roughly aligned, corner alignment is improved by sliding the C-clips 36 down over the enlarged heads 35 to the position shown in FIG. 5. This is assisted by thinning out the walls that form the legs, neck and part of the head at the bottom of the clip in the form of a taper.
The material of the clip is strong enough to help drive the walls into exact alignment as it is wedged onto the heads 35 (or tapped down on the heads with a hammer). The rib 33 and the C-clip 36 are configured such that after one no longer holds the clip it will not fall off the ribs. In this regard, as best shown in FIG. 6, there is a very tight fit of legs 38 into neck recesses 39.
If desired, the C-clip hollow 37 can be made more narrow at the top. This will prevent downward movement of the C-clip relative to the web past a selected point.
Note that the C-clip does not need to inhibit vertical movement of the enclosure walls relative to each other. Its purpose is to provide horizontal alignment assistance. When this type of system is used in combination with a vertical clamping system such as that described in the U.S. Pat. No. 4,901,380, one has an extremely efficient system that is also suitable for use with enclosures having tight corners.
The foregoing detailed description has been for the purpose of illustration. A number of modifications and changes may be made to these embodiments without departing from the spirit and scope of the invention. For example, as shown in FIG. 7, multiple clips can be used. Also, while a perfectly horizontal seam is shown, other "horizontally extending" seams can be used (e.g. have sloped or stepped seams). | A knock down type bathing enclosure is disclosed which is manufactured as a one-piece plumbing fixture, cut into two or more portions for transportation, and assembled at an installation site. In addition to having a clamping system to clamp an upper and lower portion together vertically, there is provided a corner web structure which provides for horizontal alignment through the use of a C-shaped clip and aligned ribs. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to electric contact devices which slide between two parts which move relative with to each other, a first one of said parts bearing at least one multifilament brush formed of a bundle of endless wires held at one of its ends in the first part and at its other end bearing against at least one contact zone arranged on the second part.
Sliding electric contacts are found in most electrical engineering installations both in the form of wiper shoes and in combination with collector rings or collectors of rotating machines. In the early rotating machines, the wire contactors now call brushes, have been replaced everywhere by metalgraphite or electrographite brush systems. These latter devices have their well-known limitations with respect to the current density which they can transmit, with respect to the amount of contact potential difference and the problems related to friction and wear, particularly when the speed of travel is high.
The contact pressure necessary for metallographitic brushes and the phenomena appearing at the interface between them and the contact zone of the associated rotating part have up to now limited their use to a normal or preferably inert atmosphere, preventing their use in more hostile gaseous environments and particularly in liquids.
Now the solution of this problem of immersion would satisfy very many demands. Thus, with respect to hostile gaseous conditions, the contact shoes of railway motor cars very frequently become unusable as a result of constant precipitation or due to the persistence of thick saline fogs. As for electric motors and more particularly dc motors, they rapidly prove very limited, particularly because of problems associated with brush pressure, both in aeronautics when a certain ceiling must be exceeded, and when submerged where, almost exclusively for the brush-collector subassemblies, thick-hull structures resistant to pressure must be provided, and the problems in tightness resulting therefrom must be resolved.
With a motor which is capable of operating while immersed, a thin hull enclosure, placed under equipressure, would make it possible to solve most of the structural problems and those inherent with tightness, thus permitting important developments for small auxiliary motors for equipment of submarine vehicles or underwater drilling installations. Finally, for simple matters of optimal location and utilization of available space it will be understood that the possibility of immersion, for instance of a fuel pump in an airplane wing tank, as well as in a car fuel tank, would afford very great advantages.
The conventional metallographitic or electrographitic brushes as stated above must be used in relatively controlled atmospheres and, differing from other turning parts of electrical machines encounter, when immersed in a liquid medium, almost insurmountable difficulties related to the pressure to be applied to the brushes in order to counteract the lifting force created by the "oil wedge" below the brushes and the related phenomena of electro-erosion which very rapidly make these conventional brushes ineffective.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a sliding electric contact device with a multifilament brush which permits undifferentiated use, under normal conditions or when immersed in a non-oxidizing fluid of low viscosity, whether gaseous or liquid, whatever the pressure of such gas or liquid.
Another object of the present invention is to provide a sliding electric contact device of this type which, upon operation in a gas or liquid, permits substantial current densities without a high contact potential difference at to high linear speeds.
In order to achieve this, in accordance with one feature of the present invention, the multifilament brush formed of a fixed bundle of endless wires has an overhang length which advantageously exceeds by at least 10% the normal average spacing between the two parts which are moving relative to each other and between which the electric contact is to be established.
In accordance with another feature of the present invention, the brush holder part is normally not urged towards the second part, that is to say, contrary to traditional brush holders, it is not indispensable to provide a device which provides a pressure for urging the brushes against the moving contact zone of the other part.
Sliding electric contact devices with multifilament brushes formed of thin wires of a diameter of less than 80 microns are already known which have been developed essentially to limit electrical losses and are intended for use with the application of pressure against a smooth track in a neutral or slightly reductive atmosphere. Contrary to that teaching, the applicants have discovered a technique which maintains the brush support part at a substantially constant distance from the contact area of the part facing it, without exerting on said brush holder part any pressure tending to push the brushes against the other part. The free length or overhang of the wires of said brushes extend a length greater than the normal spacing between the two parts, whereby the inherent elasticity of the component wires of the brushes make it possible to assure in a controlled manner that the required contact with the contact zone by having an elastic deformation by flexure of the free end of the bundle of wires, thus overcoming the problem of applying of a pressure against the brush holder and accordingly conditions of use in a rarified atmosphere or under conditions of high pressure.
As a matter of fact, furthermore, contrary to the teachings of the prior art, this elastic flexure of the brushes is in no way harmful to their life, particularly upon a reversal in relative displacement of the two parts. On the contrary it proves beneficial by favoring relaxation of the wires and permitting a greatly increased useful life. This latter discovery makes it possible in particular to use these brushes with rings which are no longer smooth but rather transversely grooved, and also with blade collectors while guaranteeing optimum electrical contact even under difficult gaseous conditions or when immersed in a liquid. As a matter of fact, contrary to the solid electrographitic rings, the bundle of wires, due to their flexibility and divided aspect substantially eliminates oil wedges and, by not including any vacuum-producing wake, makes it possible to obtain excellent electrical contact even with liquids having a substantial viscosity.
It will therefore be seen that the device in accordance with the present invention makes it possible to produce sliding or turning electrical contacts which are immersed in a gas or liquid which is relatively dielectric and possibly hostile as mentioned above, and also finds advantageous use in special arrangements of rotating machines.
It is known that the electric-charge transfer characteristics and the establishing of transients are greatly improved in an electric contact device by using an intermediate "wetting" agent which is a good conductor of electricity, typically a liquid metal, deposited on at least one of the contact elements.
The present invention also proposes a turning sliding-contact device in which at least a part of the interface between the first and second parts which face each other is occupied by layer of a liquid metal, advantageously arranged on the contact surface of the second part.
The property mentioned above relative to the nonformation of oil wedges and the relative insensitivity of the brushes to a relative flow of the liquid in which they are contained has made it possible to obtain entirely unprecedented results by using these brushes in a liquid-metal electric contact chamber, for instance for homopolar machines. It is known that in this type of chamber surface-contact problems between the liquid metal and the adjacent contact surfaces of the stator or rotor arise which are related to the speed of rotation and the electric fields acting on the mass of contact-liquid metal and lead to uncontrolled radial separations of the veins of liquid metal. Complicated and delicate solutions have been proposed to overcome these drawbacks, particularly by effecting a continuous reinjection of liquid metal into the chamber under high pressure.
Another object of the present invention is to overcome these defects in an effective manner without requiring auxiliary structural or power equipment by means of a reliable simple system requiring no maintenance by installing entirely immersed brushes of the type defined above at least in the zones of localized contact of such liquid metal electric contact chambers, the brushes effecting a "blocking" effect or more precisely a braking effect on the vein of liquid metal without inducing harmful disturbances in the flow of said vein while playing a supplementary role which assures electric contact in the unforeseen cases of leaks or partial emptying of the chamber.
Other characteristics and advantages of the present invention will become evident from the following description of embodiments, given by way of illustration and not of limitation, read with reference to the accompanying drawings in which:
FIG. 1 is a diagrammatic view in longitudinal section of an electric contact device in accordance with the present invention;
FIG. 2 illustrates one embodiment, applied to a rotating machine with a smooth collector ring;
FIG. 3 shows one embodiment of a rotating machine with a grooved collector ring;
FIG. 4 is a partial view in detail of one groove of the ring of FIG. 3;
FIG. 5 is a diagrammatic end view of a rotating machine with commutator;
FIG. 6 shows on a larger scale one method of mounting the brushes in accordance with the present invention;
FIG. 7 shows diagrammatically a rotating machine with liquid metal electric contact chamber in accordance with a another feature of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The device shown in FIG. 1 comprises a brush-holder part (member) 1 and an adjacent part (member) 2, which parts are capable of moving relative to each other as indicated by the arrow 10 while retaining a substantially constant average spacing e between the outer face of the brush support 5 and the outer face of the electric contact zone 4 of the part 2. In FIG. 1, the part 2 is for instance a current distribution rail, the part 1 being a contact-shoe member integral, for instance, with a motor car. The brush support part 5 is mounted rigidly on the body 6 of the part 1 or is optionally floating, with the interposition of a play take-up device 8 which does not induce any substantial force on the brush support part 5 in the direction of the track 2. At 7 there is shown a liquid or mist in which the electric contact device is immersed. In accordance with the present invention, the brushes 3 which establish the electric connection between the parts 1 and 2 and are formed of a bundle of thin metallic wires which are good conductors of electricity and easily work-hardened, comprise an embedded part 9 and a free or overhang part 9' whose length l is greater by at least 10%, and preferably 15 to 20%, than the distance e between the parts 1 and 2, so that the free end 9', in the position of use, assumes a flexed configuration as shown on the left-hand brush of FIG. 1.
FIG. 2 shows the previous system applied to a rotating machine with a smooth ring 20 against which there bear at least two rows 30, 30' of metal bundles 3', the rows extending parallel to the axis of rotation of the ring 20.
FIG. 3 shows a variant of the system of FIG. 2 in which the smooth ring 20 has been replaced by a grooved ring 20' having grooves 22 which extend parallel to the axis of rotation, these grooves defining longitudinal ribs 21 with the nominal diameter of the ring 20'. As mentioned above, although these grooves have the effect of increasing the difference in contact potential, they favor better preservation with time of the bundles of wires 30, 30' and thus make it possible to obtain greater stability for this difference in contact potential. As shown in FIG. 4, the width at the top λ of the grooves 22 is advantageously between 2 and 5 mm, the depth h of these grooves being advantageously on the order of 2 mm, determined so that the bottom of the groove 22 is at a level not capable of being reached by the ends of the wires 3 in their position of full radial extension. The angle α of the faces of the grooves is selected to be between 45° and 60° and preferably 60°.
FIG. 5 shows a similar system but applied this time to a dc rotating machine comprising a collector 20" with blades 23 separated from each other by insulating blades, for instance mica-covered blades. In FIG. 5 there can be noted the series of parallel rows of bundles of wires 3, these bundles possibly having a circular cross section or else a cross section elongated in the direction of passage of the collector blades so as to cover a number of these collector blades in order to assure good commutation and favor the reversal of the direction of rotation. The staggering of the bundles of wires with respect to the theoretical neutral line 24 of the collector blades will also be noted.
In accordance with the present invention, the wires of the brushes have a small diameter of between about 10 μm and 300 μm, preferably on the order of 60 to 100 μm. The free length l of these wires is relatively slight and is advantageously maintained less than 15 mm. The wires are made of a hard-metal alloy of good elasticity and good conductivity, for instance of cadmium or of FeSi alloy and are made by drawing, followed possibly by work-hardening. The transverse resistance of the bundles of wires can be increased artificially by insulating the wires from each other, for instance by covering them individually with a sheathing and by securing them in a resistant base 51 as shown in FIG. 6. The flexibility of the wire brushes and their only slight abrasive character permit for the contact tracks or zones 4 of the rings 20, 20' any suitable electrically conductive material such as copper or copper-zirconium alloys.
As shown in FIG. 1, the brushes 3 may be fixed in a copper support 5 or, as shown in FIG. 6, with their inner ends engaged in a cup 52 formed in a copper part 50, the fixing of the wires and the determination of their free length being obtained by a perforated plate 51 of insulating material. The same structure can be used with a plate 51 which is no longer of a material which is a non-conductor of electricity but of a material which is a good conductor and forms a radiator for the evacuation of the heat dissipated in the wires. The latter, as shown in FIG. 6, can be put in place in the manner of tufts in brush-making, each bundle being formed of a package of wires bent as a hair pin and held in the cup 52 by a loop 53, for instance of brass wire, the bundles being connected on the rear face of the plate 50 by another brass wire 54.
Typically, the wires are combined in bundles having a diameter of less than or equal to 10 mm and are assembled in parallel rows close to each other so that the wires of the different bundles can touch upon flexure. More particularly, in collector machines, the bundles can be arranged along a stagger as a function of the contemplated current density. The arrangement in accordance with the present invention permits current densities of up to 100 amperes/cm 2 at linear speeds of passage of up to 50 m/s -1 and above, permitting a life, upon immersion in non-oxidizing dielectric liquids or gases, of up to several thousands of hours. These characteristics can be further increased by incorporating lubricating filaments in the bundles of wires.
The arrangement in accordance with the present invention has proved effective for punctiform uses in any liquid or gas which is relatively non-oxidizing and of a resistivity of less than 0.5 ohms/meter (for instance sea-water), the very slight abrasive effect of the brushes on the contact surface of the second part making it possible to preserve a thin film of protective gold deposited on said surface for a long period of time. With liquids of a viscosity of less than 100 centipoises, such as mineral oils, hydrocarbons or potash brines, the device has proven to have a very satisfactory life.
The ability of the brushes to maintain the electric contact when immersed in a liquid, even at high speeds, also makes it possible to use the electric contact device of the present invention in rotating systems with electric contact assured, at least in part, by a liquid metal compatible with the material of the brushes, such as HgIn or the eutectic NaK. In particular, in any type of smooth-ring machine, one can advantageously deposit a thin layer of liquid metal on the surface of said ring, as shown at 31 in FIG. 2, this liquid metal assuring a "wettability" effect of said surface which considerably improves the quality of the electric contact with the brushes 30 whose free contact ends will furthermore be provided permanently with a small amount of said liquid metal, which is held in particular by capillary action.
FIG. 7 shows a particularly important development of the present invention. This figure diagrammatically shows a homopolar machine with contact by liquid metal, the outer induction Bo being created, for instance, by a supraconductive solenoid to reach values on the order of several Teslas. The disk 200 which is secured fast to the shaft 40 of the rotor is mounted in a cylindrical chamber 41 so as to define with the stator shell elements 100, 101 two annular localized contact zones I and II for the passage of the current i whose path is shown in dot-dash line, the closing of the current circuit being assured in the contact zones by the liquid metal 42 which at least partially fills the chamber 41, this metal or alloy having wetting-agent characteristics, a high conductivity and a large range of temperature between its boiling point and freezing point. The electrically insulated surfaces of the chamber are shown in insulator hatchings. In accordance with the present invention, within the contact zones I and II there are arranged, between the stationary elements 100 and 101 and the periphery of the disk 200, at least two rows of bundles of wires 30 of the type defined above, the object of which is in particular to "calm" or block the placing in rotation due to Laplace forces of the vein of liquid metal in these zones by substantially slowing the relative excess speeds of these veins and thus permitting improved operation at low cost of the machine for high speeds of rotation.
Although the present invention has been described in connection with special embodiments, it is not limited thereto but rather is capable of modifications and variants which will be evident to the man skilled in the art. | Sliding electric contacts are disclosed which may be used, for example, to maintain electrical contact between two moving parts in a rotating machine. Electrical contact between two such parts separated by a constant average distance is maintained during movement of the parts by use of at least one multifilament brush formed as a bundle of thin wires having a fixed end and a free end wherein the free end has a length which is at least 10 percent greater than the constant average distance between the moving parts. The moving parts may be in the form of various configurations of commutators and the electric contacts may be used to maintain electrical contact between the parts within a fluid medium. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cellular telephone, and more particularly, to a cellular telephone with an improved LCD supporting frame.
2. Description of the Prior Art
Typically, the LCD panel of a cellular telephone is supported horizontally above the main circuit board by a supporting frame. An auxiliary circuit board with a light source is installed vertically at one end of the supporting frame and a light guiding panel is installed horizontally on the supporting frame for passing light emitted from the light source upward onto the LCD panel as backlight. The auxiliary circuit board is soldered onto the main circuit board thus fixing it to the supporting frame and allowing inward passage of current. The contacting surface and soldering area of the auxiliary circuit board and main circuit is small and there is no room to install any circuits other than a simple light source circuit. The soldering area is further limited during installation of the supporting frame and auxiliary circuit board onto the main circuit board due to the complexity of the cellular telephone. Installing the supporting frame and auxiliary circuit board is not an easy task.
SUMMARY OF THE INVENTION
It is therefore a primary objective of the present invention to provide a cellular telephone with an auxiliary circuit board having a light source and a peripheral circuit to solve the mentioned problem.
In a preferred embodiment, the present invention provides a cellular telephone comprising:
a housing;
a main circuit board horizontally installed in the housing and comprising a first surface connector having a plurality of metal conductors installed on an upper surface of the main circuit board;
an LCD (liquid crystal display) panel installed above the main circuit board for displaying images;
a supporting frame latched to the main circuit board for supporting the LCD panel above the upper surface of the main circuit board;
an auxiliary circuit board vertically installed at one end of the supporting frame having a light source, a peripheral circuit, and a second surface connector in it, the second surface connector comprising a plurality of metal conductors corresponding to the metal conductors of the first surface connector, the second surface connector being electrically wired to the light source and the peripheral circuit on the auxiliary circuit board;
a light guiding panel horizontally mounted between the LCD panel and the supporting frame for passing light emitted from the light source upward onto the LCD panel so as to provide backlight to the LCD panel; and
an elongated zebra connector horizontally mounted to a bottom side of the supporting frame and comprising a bottom side and an elongated vertical side.
It is an advantage of the present invention that the cellular telephone according to the present invention solves the soldering problem by facilitating the combination of components. At the same time, it reduces the number of components and simplifies the general structure of the cellular telephone.
This and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiment which is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the components of a cellular telephone according to the present invention.
FIG. 2 is a perspective view of the auxiliary circuit board installed at one end of the supporting frame.
FIG. 3 is a perspective view of the zebra connector mounted to a bottom side of the supporting frame.
FIG. 4 is a perspective diagram of the zebra connector shown in FIG. 1 .
FIG. 5 is a perspective view of the supporting frame latched to the main circuit board.
FIG. 6 is a perspective view of the LCD panel installed above the supporting frame.
FIG. 7 shows the components of another cellular telephone according to the present invention.
FIG. 8 is a perspective view of the supporting frame shown in FIG. 7 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Please refer to FIGS. 1 to 3 . FIG. 1 shows the components of a cellular telephone 10 according to the present invention. FIG. 2 is a perspective view of the auxiliary circuit board 18 installed at one end of the supporting frame 16 . FIG. 3 is a perspective view of the zebra connector 20 mounted to the bottom side of the supporting frame 16 . The cellular telephone 10 comprises an upper chassis (not shown), a lower chassis (not shown), a main circuit board 12 horizontally installed in the lower chassis, an LCD (liquid crystal display) panel 14 installed above the main circuit board 12 for displaying images, a supporting frame 16 latched to the main circuit board 12 for supporting the LCD panel 14 above the upper surface of the main circuit board 12 , an auxiliary circuit board 18 vertically installed at one end of the supporting frame 16 having a light source (not shown) and a volume control module 30 , a light guiding panel 17 horizontally mounted between the LCD panel 14 and the supporting frame 16 for passing light emitted from the light source upward onto the LCD panel 14 so as to provide backlight to the LCD panel 14 , an elongated zebra connector 20 horizontally mounted to the bottom side of the supporting frame 16 , and a supporting base 21 for supporting the zebra connector 20 . The auxiliary circuit board 18 comprises two vertical sides with a light source installed at the side facing the supporting frame 16 and a volume control module 30 installed on the other side for controlling the volume of the cellular telephone 10 .
Please refer to FIG. 4 . FIG. 4 is a perspective diagram of the zebra connector 20 shown in FIG. 1 . The main circuit board 12 comprises a first surface connector 22 having a plurality of metal conductors 24 on its upper surface. The auxiliary circuit board 18 has a second surface connector 26 which comprises a plurality of metal conductors 28 corresponding to the metal conductors 24 of the first surface connector 22 and is electrically wired to the light source and the volume control module 30 . The zebra connector 20 contacts the first surface connector 22 with its bottom surface and also contacts the second surface connector 26 with one of its sides. It is made of conductive rubber.
Please refer to FIGS. 5 and 6. FIG. 5 is a perspective view of the supporting frame 16 latched to the main circuit board 12 . FIG. 6 is a perspective view of the LCD panel 14 installed above the supporting frame 16 . When the upper and lower chassis of the cellular telephone 10 are attached, the LCD panel 14 , supporting frame 16 and main circuit board 12 will be clamped in sequence between the upper and lower chassis. The auxiliary circuit board 18 is fixed onto the main circuit board 12 while the supporting base is pressed downward, pressing the zebra connector 20 and bringing it in close contact with the first surface connector 22 and second surface connector 26 . The electrical connection between the corresponding metal conductors 24 and 28 of the first 22 and second surface connectors 26 can thus be maintained.
As shown in FIG. 3, the bottom of the supporting frame 16 comprises two protruding knobs 32 installed at the two ends of the side 36 . As shown in FIG. 1, the main circuit board 12 has two through holes 34 corresponding to the two protruding knobs 32 so that the two protruding knobs 32 of the supporting frame 16 can be inserted into the two corresponding through holes on the main circuit board 12 . Because only one side 36 is fixed to the main circuit board 12 , the inner (non-fixed) side of the upper chassis has to match the upper side 38 of the auxiliary circuit board 18 . Thus, when the upper and lower chassis are connected, the supporting frame 16 and auxiliary circuit board 18 can be fixed to the main circuit board 12 . Also, the zebra connector 20 is in close contact with the first and second surface connector 22 , 26 so that the electrical connection between the corresponding metal conductors 24 , 28 can be maintained.
Please refer to FIG. 7 and FIG. 8 . FIG. 7 shows the components of another cellular telephone 40 according to the present invention. FIG. 8 is a perspective view of the supporting frame 41 shown in FIG. 7 . The bottom of the supporting frame 41 comprises four protruding knobs 42 , and four corresponding through holes 44 installed on the main circuit board 12 . The four protruding knobs 42 of the supporting frame 41 are inserted into the four corresponding through holes 44 on the main circuit board 12 to fix the supporting frame 41 to the main circuit board 12 and to bring the zebra connector 20 in close contact with the first surface connector 22 of the main circuit board 12 . Using this design, the supporting frame 41 can be firmly fixed to the main circuit board 12 without pressing the auxiliary circuit board 18 with the upper chassis. Thus, the design of the upper chassis of the cellular telephone 40 is simpler, and it is easier to fix the upper and lower chassis together.
In contrast to the prior art cellular telephone, in the present invention, the light source and volume control module 30 of the cellular telephone 10 , 40 are installed on two sides of the auxiliary circuit board 18 which is secured to the supporting frame 16 , 41 thus optimizing the positioning effect of the light source and volume control module 30 . Also, electricity is conducted between the main circuit board 12 and the auxiliary circuit board 18 by the zebra connector 20 which has the capability of conducting to vertically neighboring surfaces. If the design of the peripheral circuit of the auxiliary circuit board is to be changed to increase functionality of the cellular telephone 10 , 40 , the number of metal conductors 24 , 28 is simply increased. Therefore, The cellular telephone of the present invention facilitates the combination of components, reduces the number of components, simplifies the structure of the telephone and does not require soldering.
Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teachings of the invention. Accordingly, the above disclosure should by construed as limited only by the metes and bounds of the appended claims. | The present invention provides a cellular telephone with an auxiliary circuit board having a light source and a volume control module and comprising a horizontal main circuit board, an LCD (liquid crystal display) panel, a supporting frame, an auxiliary circuit board with a light source, a light guiding panel, and a zebra connector. In the production of the cellular telephone, no complicated soldering is required. In addition, the number of components are reduced and the general structure is improved and simplified. | 7 |
This application is a division of application Ser. No. 10/132,470 filed on Apr. 26, 2002, now U.S. Pat. No. 6,936,138.
BACKGROUND
This invention relates to a method and apparatus for incorporating feature substances into a paper web and to a paper machine having such an apparatus.
It is known to incorporate feature substances into documents of value made of paper, in particular bank notes, as security features, for example luminescent particles fluorescing in a characteristic color under suitable excitation radiation such as UV light. Feature substances refer here in general to substances with certain physical properties whose presence and/or arrangement can be checked due to these properties by measurement technology, for example by suitable sensors. Such features are usually placed at defined positions in the paper as characters, patterns or lines.
It is known for example from DE-A-197 54 776 to spray colored patterns with sharp contours onto finished paper in linear form so as to produce graphic security features recognizable to the naked eye. Said security features are deposited on the surface of the paper and are therefore not only visible but also tangible. In particular when using luminescent substances whose color effects are only recognizable under certain excitation conditions, however, it is desirable that their place of incorporation is inconspicuous to the casual viewer and in particular to possible forgers.
UK-A-696 673 proposes for example injecting coloring pigments in a suspension liquid immiscible with water into the center of the sheet from a jet or nozzle during sheet formation to produce dotted lines or continuous pipes, for example of material fluorescent in UV light. However, since the fluorescent suspension spreads at least partially and uncontrollably in the not yet fully dipped paper material, the contours of such lines are blurred and the pigment concentration is uneven across the line width.
DE-C-497 037, in contrast, proposes applying, for example spraying, a suspension with fluorescent substances onto the fully dipped, still moist paper web in such a way that the paper structure itself does not undergo any appreciable change. However, spraying also leads to patterns whose contour acuity is difficult to control and whose feature concentration is inconstant across the surface of the pattern.
These disadvantages are partly overcome by the method described in UK-C 643 430 wherein an endless metal band with stencil-like gaps is moved together with the arising paper web and the colored feature substances are sprayed on diffusely so as to penetrate into the paper web in the area of the stencil-like gaps. However, this also fails to obtain a sufficiently homogeneous distribution of feature substances, as EP-A-0 659 935 criticizes.
EP-A-0 659 935 instead proposes dispersing feature substances not in suspension but in gas, so that agglomerates of feature particles readily break down and are present in the gas in a defined, homogeneous concentration, to then be sprayed onto the still wet paper web by a nozzle. This is said to achieve a homogeneous distribution in paper at the same time as relatively sharp contours even at low feature concentrations.
The disadvantage of this aerosol application of the particles is that only few feature substances are suitable for application in aerosol form since the pipes and nozzles are easily clogged. This applies in particular to fine-grained feature substances which tend to agglomerate. Furthermore, test results have shown relatively high fluctuations in concentration so that a high feature concentration is necessary for obtaining reliably measurable features.
SUMMARY
The problem of the present invention is therefore to propose a method and apparatus as well as a corresponding paper machine which make it possible to incorporate feature substances into paper in patterns or tracks with sharp contours and concentrations as uniform as possible across the pattern surface, even if they are low, without this resulting in changes of the fiber structure of the paper which are visible to the eye.
As in DE-C 497 037, the feature substances are, according to the present invention, incorporated into the paper web during the papermaking process at a time when the bulk of the liquid is already withdrawn from the original paper pulp, i.e. the paper web is still moist but already consolidated, by applying a feature substance suspension to the still moist paper web in such a way that the paper web does not undergo any change in fiber structure. In order to achieve this, the feature substance suspension is directed onto the surface of the paper web as a laminar jet with low jet pressure. The feature substance suspension flows onto the paper web at low pressure.
The low jet pressure, this referring to the pressure on the inlet side of a nozzle, prevents the fiber structure of the paper web from changing upon application of the feature substance suspension. Accordingly, the place where the feature substance suspension is applied is invisible to the naked eye on the finished paper, even in transmitted light. Therefore, the method can also be used for incorporating feature substances in the watermark area.
A jet pressure on the nozzle inlet side in the range of about 30 to 200 millibars, preferably 50 to 100 millibars, has proved especially suitable. A nozzle inlet pressure therebelow leads to uneven and unstable jet formation and to deposits of feature substance in the feed pipes, while a higher nozzle inlet pressure from about 250 millibars upwards leads to structural changes in the fibrous web of the paper web. The outlet nozzles themselves can be designed very simply, for example as metal or ceramic tubes. However, it is especially suitable to use so-called solid jet nozzles or flat jet nozzles which discharge the feature substance suspension as a solid jet with a circular or flat cross section.
The extension of width of the feature track is empirically determinable, and almost constant if the quantity of suspension is supplied constantly. The patterns produced thereby therefore have sharp contours. Since the suspension jet directed onto the paper web penetrates the wet and still soft paper layer uniformly, the quantity of suspension applied is roughly constant across the surface. As a result, the feature concentration is almost homogeneous across the width of the produced pattern, regardless of how high the feature concentration in the suspension is. This makes it possible to produce patterns even with the lowest feature concentrations distributed homogeneously over the pattern surface. The feature concentration of the produced patterns can be so low that the features are invisible to the naked eye and only detectable by machine using suitable sensors.
Since the feature substances are incorporated on a liquid basis, one can use almost any type of feature substances which are dispersible or soluble in a suitable suspending medium. Even high-density pigments can thus be incorporated uniformly into the paper web. Incorporating the feature substances by means of solid jets has the further advantage over spraying methods that no mist occurs. Thus the equipment used does not soil as easily and there are fewer problems with the deposit of particles on the nozzles.
The feature substances are preferably dispersed in water since water is available anytime, inexpensive, safe and chemically neutral. This does not exclude the use of other liquids such as alcohol. Especially suitable feature substances are luminescent pigments which are only recognizable under special excitation conditions such as UV light, so that the feature patterns incorporated into the paper are not readily visible in daylight. However, magnetic feature substances or ones absorbent in certain wave ranges can also be processed with the inventive method and apparatus.
The laminar feature substance suspension jet is preferably directed onto the paper web directly after sheet formation and removal of the still soft paper web from the mold, since at this point the paper web is sufficiently consolidated but still so moist that the suspension with the feature substances can penetrate into the paper web without leaving any traces. A special embodiment provides that a suction device in the form of a separate suction box is disposed at a following place in the paper machine in the direction of transport of the paper web for sucking the suspending medium through the paper web. This promotes the feature substances being present not only in near-surface areas of the paper but distributed throughout the paper thickness.
An essential aspect in producing the feature patterns in the paper is that the feature substance suspension applied to the paper web at all times has a precisely defined feature substance concentration level so that a test of the paper always leads to the same result, regardless of the place in the paper where the produced feature pattern is tested. For this purpose, an advantageous embodiment of the invention provides that the feature substance suspension is constantly circulated in a volume and thereby intermixed, being preferably conveyed continuously in a closed circuit. This procedure is especially advantageous since in particular a continuous circulation and intermixture of the feature substance suspension makes it unnecessary to use any chemical additives for stabilizing the suspension, such additions usually having undesirable effects on the paper web formation.
The volume should have a certain size since it serves as a buffer volume which compensates for fluctuations in the concentration of the feature substance in the volume which are caused by the supply of further feature substance concentrate and suspending medium into the volume. Said volume must not be too great, on the other hand, since otherwise any changes to be made in the set point of the feature substance concentration last too long. It has proved expedient to select the size of the volume so that an exchange or the throughput of the volume through the nozzles lasts about 15 minutes.
A further important aspect, which is to be heeded in particular when producing paper webs with multiple-copy sheets whereby several identical feature patterns are regularly incorporated simultaneously, is that the pressure at which the feature substance suspension is directed onto the paper web in different places is identical in each case. For this purpose it is provided that a great number of up to several hundred connecting pipes branch off from the closed, continuously conveying feature substance suspension circuit to nozzles from which feature substance suspension is directed onto the paper sheet in laminar jets. This necessarily involves a pressure loss in the closed circuit. Like the pressure loss through the flow resistance of the circuit, it means that an individual suspension pressure or connecting pipe inlet pressure is present depending on the place where the connecting pipe leading to the nozzle branches off from the circuit, said pressure having to be reduced up to the nozzle just so far that the same outlet pressure is present at all nozzles used for producing similar patterns. This can be realized for example by a special control device in each connecting pipe. A simpler and therefore preferred solution, however, is to select the length and/or diameter of the connecting pipes so that the pressure loss in the connecting pipes is just so high that the nozzle outlet pressure is identical in each case.
The connecting pipe inlet pressure depends, on the one hand, on how high the maximum suspension pressure in the closed circuit is and, on the other hand, on how high the pressure loss in the circuit is up to the branching-off of the connecting pipe in question. Said pressure loss in turn depends directly on the rate at which the feature substance suspension is conveyed within the circuit. Preferably, the feed or circulating pump is operated at high and constant delivery to produce a circulation rate as high as possible and thus a turbulent flow which prevents sedimentation of the feature particles while simultaneously achieving uniform intermixture of the suspension. Maintaining the circulating pump delivery constant ensures constant conditions in the pipes and nozzles during operation. The operability and effect of the pump is monitored by measurement of a pressure difference. For this purpose the pressure in the circuit can be measured before and after the connecting pipe branches and the delivery of the circulating pump inferred from the differential pressure measured. Both wear of the circulating pump due to abrasive properties of the suspended particles and a reduction in cross-sectional area due for example to deposits in the pipes or filters of the circuit lead to a decrease in the pressure difference measured in the circuit. Monitoring of the pressure difference thus permits countermeasures to be taken in time.
A control device is preferably provided for maintaining the maximum or absolute suspension pressure in the circuit constant. For this purpose the absolute pressure is measured at a suitable place in the volume and the quantity of suspending medium supplied to the volume controlled by a feed pump. Although feature suspension is continuously removed from the volume via the nozzles, the essential parameters remain constant in the volume and thus also on the nozzles.
Alternatively, the conveyed or circulated quantity can be monitored and maintained constant, instead of the pressure in the removing volume. In this case, suspension fractions withdrawn from the volume are also compensated for and constant conditions ensured. Pressure control has the advantage, however, that it ensures that the same quality of suspension leaves each nozzle if the nozzles are the same, regardless of the number of open nozzles. This is of advantage in particular when a fast change is to be made in the coding produced in the paper with the suspension jets while paper web production is underway.
It is important for the operability of the apparatus for applying feature substance suspension to the paper web that there are no deposits, in particular of feature substances, in individual elements of the apparatus since this can have an adverse effect on the pressure relations in the apparatus and thus on the uniformity of the produced feature patterns. Therefore it is provided that the feature substance suspension is produced in the desired concentration substantially only in the volume from which the connecting pipes branch off to the jet outlet nozzles, i.e. only in the closed circuit system in the case of the specific preferred embodiment. A feature substance concentrate and the suspending medium are therefore supplied to the circuit separately, preferably locally before the pump for circulating feature substance suspension in the closed circuit, so that said circulating pump performs the function of mixing the feature substance concentrate with the suspending medium.
In addition it is advantageous to provide a degassing device for degassing the suspending medium before it is supplied to the volume. This ensures, among other things, that the suspension does not emit gas and form bubbles, in particular upon a drop in pressure. In the degassed medium, air bubbles already present in the feature substance suspension can also dissolve again. If such air bubbles were discharged from the nozzles with the feature substance suspension, this would have an adverse effect on the contour and concentration distribution of feature substance at this place in the finished paper. For similar reasons the connecting pipes are preferably connected to the volume from above and protrude into the volume so that any air bubbles contained in the volume cannot pass into the connecting pipes and in addition no feature substances sedimented in the volume can pass into the connecting pipes and block them. In particular with especially high-density feature substances there is the danger of some larger particles being deposited on the bottom of the volume.
In preferred embodiments, shut-off devices are provided between the discharge points of the suspension from the buffer volume and the nozzles to permit each individual nozzle to be switched on and off individually. The shut-off devices can be for example stopcocks or valves which are controlled manually or automatically and actuated manually, electronically or pneumatically. This makes it possible to produce in a paper web an individual or regularly recurring feature pattern, which can also consist of interrupted tracks and also render coded information. In particular with automatically controlled switching apparatuses one can produce feature patterns whose application or incorporation in the paper web is synchronized with marks located thereon. In a preferred embodiment, said marks are formed by watermarks present in the paper.
BRIEF DESCRIPTION OF THE DRAWING
In the following, FIG. 1 shows a schematic view of an apparatus in a paper machine.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Only a tiny detail of the paper machine is shown, namely the end of mold 1 . Paper web 2 , shown by dash lines, leaves mold 1 in the direction of the arrow. In this state, paper web 2 is already largely consolidated but still moist. Paper web 2 leaving mold 1 is transported further and guided under nozzle rail 10 . Through nozzles 11 a feature substance suspension is directed onto the moist paper web from above in order to produce linear feature patterns in the paper web parallel to the outside edge of the paper web. Several hundred nozzles 11 can be provided side by side which are individually activable and deactivable via associated stopcocks 12 . Following nozzles 11 in the transport direction of the paper web is suction device 3 which is provided under paper web 2 to suck feature substance suspension applied to paper web 2 by nozzles 11 through paper web 2 so that only the feature substances are left in the paper. As indicated by the FIGURE, said suction device can already begin before nozzles 11 in the transport direction of the paper web. Paper web 2 is then supplied optionally to following processing stations (not shown) for drying, coating, printing and the like.
The apparatus for incorporating feature substances into paper web is composed substantially of four subsystems. The core element of the apparatus is a volume preferably defined as a closed circuit 13 of nozzle rail 10 formed as a pipe system and having centrifugal pump 14 as a circulating pump for continuously conveying feature substance suspension within the pipe system. The second subsystem is formed by water preparation and supply unit 20 , and the third subsystem by feature substance concentrate preparation and supply unit 30 . The fourth subsystem is formed by nozzles 11 and their connecting pipes 15 to closed circuit 13 of nozzle rail 10 . The various subsystems will be described in detail below.
Feature substances are held ready as feature substance concentrate in a storage vessel. Through cover opening 32 feature substances are supplied to vessel 31 in pulverized form. Water is supplied via blockable feed pipe 33 . Water and feature substances are mixed by agitator 34 , and the feature substance concentration is preferably in the range of 10 to 30 wt %, in particular 0.4 kg of feature substance for 1 liter of water. The exact concentration value in the storage vessel is relatively uncritical since the final concentration of the feature substance suspension directed onto paper web 2 by nozzles 11 is only adjusted in closed circuit 13 by admixture of water. The higher the concentration in the storage vessel, the greater the feature supply and thus the time period until the storage vessel is refilled. The fill level of the storage vessel is monitored with level gage 35 . However, the concentration in the storage vessel must not exceed a predetermined viscosity limit of the feature concentrate since this otherwise impairs the feed of feature concentrate by means of metering pump 36 preferably formed as a diaphragm pump. At the abovementioned concentration values the features substance suspension is still very liquid, almost like water, for most feature substances. Via feed pipe 38 , metering pump 36 finally pumps feature substance concentrate out of storage vessel 31 into closed circuit 13 of nozzle rail 10 .
Prepared water is in addition supplied to closed circuit 13 via feed pipe 28 . The water is previously degassed in vacuum vessel 21 holding for example 20 liters at a negative pressure of approximately 0.3 bars relative to ambient pressure, so that any air bubbles passing into closed circuit 13 with the feature substance concentrate for example can dissolve in the feature substance suspension of closed circuit 13 . The vacuum vessel is equipped with vacuum pump 27 and level gage 25 which ensures that the fill level is maintained at about 90% of capacity for safety reasons. A feed pump executed for example as gear pump 26 conveys prepared water out of vacuum vessel 21 via feed pipe 28 to closed circuit 13 . The maximum delivery of gear pump 26 is for example about 550 liters an hour, which suffices for supplying about 300 nozzles simultaneously with a throughput of about 1.7 liters an hour per nozzle. Water treatment and supply unit 20 preferably has a water deliming device additionally integrated therein, which is not shown in the FIGURE.
Closed circuit 13 is formed substantially by a closed pipe system with integrated centrifugal pump 14 for circulating feature substance suspension conveyed in closed circuit 13 . Feature substance concentrate and prepared water are supplied to closed circuit 13 via feed pipes 38 , 28 shortly before centrifugal pump 14 . Centrifugal pump 14 thus performs the function of intermixing supplied feature substance concentrate with supplied prepared water. This guarantees that the concentration distribution of feature substances in the feature substance suspension is homogeneous to a very large extent before feature substance suspension fractions are branched off from circuit 13 via connecting pipes 15 to nozzles 11 . Strainer 16 with a 100 micron steel screen is provided shortly after the centrifugal pump and retains particles which could lead to clogging of nozzles 11 . Stopcock 17 is provided for example on the strainer screen for ventilating the apparatus after it is switched on.
Closed circuit 13 has two control circuits, a pressure control circuit and a density control circuit.
The pressure control circuit includes two pressure sensors P 1 and P 2 at different places in closed circuit 13 , preferably at a place before the branchings-off of connecting pipes 15 to nozzles 11 and at a following place in the direction of circuit flow. Pressure p 1 can be for example between 500 and 800 millibars depending on the pipe lengths and cross sections. Deviations from this set point are measured and used for controlling gear pump 26 for conveying the prepared water so that set point p 1 is maintained. Pressure value p 2 is preferably measured after the branching-off of last connecting pipe 15 to last nozzle 11 to determine the drop in pressure arising due to the branched-off feature substance suspension fractions and the flow resistance of the pipes in closed circuit 13 . Said drop in pressure should always be constant to ensure that roughly the same pressure relations always prevail at all nozzles 11 regardless of the number of nozzles activated. Since pressure differences p 1 −p 2 is directly dependent on the flow rate of feature substance suspension in closed circuit 13 , differential pressure measured value p 2 −P 1 is used to monitor the delivery of centrifugal pump 14 .
The density control circuit includes density sensor p. The inlet of density sensor p is connected directly to closed circuit 13 directly after strainer 16 . The outlet of density sensor p is located on the opposite side shortly before the inlet to centrifugal pump 14 . The pressure drop between inlet and outlet ensures sufficient flow through density sensor p which prevents deposits from forming in density sensor p. Density sensor p is used to determine the actual density of feature substance suspension in closed circuit 13 . This is a measure of the concentration of feature substances in the feature substance suspension of closed circuit 13 . According to the information on the actual density of feature substance suspension provided by density sensor p, metering pump 36 on storage vessel 31 is controlled to adjust a predetermined set point of suspension density corresponding to a concentration of a feature substance. A typical density adjustment for metering feature substances in feature substance suspension is e.g. 0.1 to 0.5 wt %.
The aforementioned measures ensure that not only the same feature substance concentration is present in the feature substance suspension at every branching-off of connecting pipe 15 , but also a time-constant connecting pipe inlet pressure, although it varies from connecting pipe to connecting pipe. On these premises the same connecting pipe outlet pressure can be adjusted for all pipes by simple constructional design of the connecting pipes, by producing a defined pressure loss in each connecting pipe 15 by suitable choice of the diameter and/or preferably the length of connecting pipes 15 , so that the same pressure is present at the end of each connecting pipe, that is, at nozzles 11 . To achieve the same outlet pressure for all nozzles 11 for example at pressure p 1 in the range of 500 to 800 millibars and an accordingly lower value for p 2 in closed circuit 13 , connecting pipes 15 with a length of typically a few decimeters have provided suitable, the connecting pipes consisting for example of tubes with an inside diameter of about 1 millimeter.
Each connecting pipe 15 has individual stopcock 12 . However, the blockage of individual stopcocks 12 has no effect on throughput and nozzle outlet pressure, since the connecting pipe inlet pressure is maintained roughly constant by the above-described pressure control regardless of the number of active nozzles.
Stopcocks 12 can be replaced by shut-off valves. An electric or pneumatic drive (not shown in the FIGURE) of the shut-off devices is advantageous in particular for frequent or fast change of the produced coding patterns. Altogether several hundred nozzles can be disposed side by side, also offset, at a distance of about 3 to 15 millimeters.
It should also be mentioned that connecting pipes 15 are connected to closed circuit 13 from above to prevent larger feature substance particles deposited on the bottom of closed circuit 13 from being sucked in, which could lead to clogging of the components such as stopcocks, nozzles, etc. In addition, connecting pipes 15 protrude from above about 10 millimeters into closed circuit 13 to prevent any air bubbles from being discharged through nozzles 11 with feature substance suspension, which would have an adverse effect on the quality of the stripe pattern produced.
The above-described apparatus for incorporating feature substances into a paper web permits a great variety of line codings by activating and deactivating individual nozzles 11 using respective associated stopcocks 12 without this having an effect on the feature substance concentration of the individual lines ultimately present in the finished paper. This is essentially due to the special pressure control circuit wherein the absolute pressure in the volume, e.g. pressure p 1 , is measured in closed circuit 13 before the branching-off of connecting pipes 15 and pressure p 2 after branching-off of connecting pipes 15 , each being maintained at a constant value by control of the delivery of gear pump 26 . The advantages achieved by said pressure control circuit are also achieved when the feature substance suspension is directed onto the surface of the paper web not as a laminar jet with low jet pressure but for example with high jet pressure or as a turbulent jet or sprayed jet. | A method and apparatus for incorporating feature substances into a still moist but already sufficiently consolidated paper web provides for directing a feature substance suspension onto the surface of the paper web as a laminar jet with low jet pressure. A special pressure control circuit ensures that the jet pressure is always constant regardless of the number of parallel feature substance suspension jets directed onto the paper web. This makes it possible to incorporate a great variety of line codings in paper under the same process conditions without any visible changes in fiber structure occurring in the paper. | 3 |
RELATED APPLICATIONS
[0001] This application is a continuation in part of U.S. patent application Ser. No. 12/911,723, filed Oct. 25, 2010, which is a continuation in part of U.S. patent application Ser. No. 10/588,079, filed Nov. 22, 2005, entitled “Methods For the Selective Treatment of Tumors by Calcium-Mediated Induction of Apoptosis,” which claims priority to U.S. provisional application Ser. No. 60/475,063 entitled “Methods For the Selective Treatment of Tumors by Calcium-Mediated Induction of Apoptosis,” filed May 30, 2003; the entire disclosures of which are hereby incorporated by reference. Any disclaimers that may have occurred during the prosecution of the above-referenced applications are hereby expressly rescinded, and reconsideration of all relevant art is respectfully requested.
TECHNICAL FIELD
[0002] This present disclosure is in the field of medical therapeutics, more particularly in the field of clinical treatment of malignancy and cancer therapy. The methods allow a broad range of human tumors or cancer types to be treated by selectively inducing apoptosis. Apoptosis is induced in tumors by disrupting intracellular calcium distribution in a manner that leaves normal growing or non-growing cells unharmed.
BACKGROUND
[0003] Warburg described a metabolic “defect” in energy utilization exhibited by most cancer cells. This “defect” is now known to result from a change in mitochondrial function. Many different mutations in initial growth factor dependent pathways function to produce a state in which cells are made capable of continuously passing the Pardee Restriction Point (RP) or point of no return towards the end of the G1 phase of the cell cycle. It is demonstrated that traverse through G1 prior to this point is dependent on the continuous availability of EC (extra celluler) Ca 2+ . Any growth factor requirement for passing the RP is bypassed completely by Ca++-specific ionophores as long as there is a ready supply of EC Ca 2+ Carcinogenic Phorbol analogs, which act to stimulate certain forms of Ca 2+ dependent PKC, can replace the growth factor requirement for crossing the RP, as long as there is sufficient EC Ca 2+ present in the growth medium. The present disclosure teaches these steps can be short-circuited and effectively bypassed by providing a ready supply of EC Ca 2+ consistent with the known requirement for IC (intra cellular) but not EC Ca 2+ upon passing the RP. Effectively, malignant transformation mimics the effect of Ca 2+ ionophores and Phorbol compounds and the initiating event in cancer is any mutation which produces an increased new steady state of continuous Ca 2+ influx. In order for such cells to escape Ca 2+ -induced apoptosis, several adaptations in IC Ca 2+ -handling must occur if such a potentially cancerous cell is to survive to a detectable disease state. This does not exclude the influence of known mutations in tumor suppressor or tumor promoter genes either prior to or selected for once the initiating stimulus for malignancy occurs in exacerbating the malignant state, but these mutations must be secondary to satisfying the Ca 2+ requirement for passing the RP.
[0004] The present disclosure teaches the use of calcium manipulation for the treatment of cancer.
SUMMARY OF THE EMBODIMENTS
[0005] The disclosure teaches a method for treating a cancer in a patient comprising administering to said patient effective amounts of two or more drugs at concentrations which interact synergistically, that stimulate an increase in the Ca 2+ burden of smooth endoplasmic reticulum and mitochondria. The term cancer can mean a tumor in a patient. In one embodiment, the drug concentrations are submaximal. In one embodiment, at least one of said drugs stimulates Smooth-Endoplasmic-Reticulum Ca 2+ -ATPase (SERCA) and wherein at least one of said drugs is an antagonist of SER Ca 2+ gates.
[0006] The disclosure teaches a method for treating a tumor in a patient comprising administering to said patient effective amounts of two or more drugs at concentrations which interact synergistically, that stimulate an increase in the Ca 2+ burden of smooth endoplasmic reticulum and mitochondria.
[0007] In one embodiment at least one of said drugs stimulates Smooth-Endoplasmic-Reticulum Ca-ATPase (SERCA) and wherein at least one of said drugs is an antagonist of SER Ca 2+ gates.
[0008] In one embodiment at least one of said drugs is selected from the group consisting, inhibitors of SER IP3-sensitive Ca 2+ gates and SERCA agonists, and one of said drugs are selected from the group of drugs which are stimulators of particulate guanylate cyclase. In one embodiment at least one of said drugs is selected from the group consisting of inhibitors of SER IP3-sensitive Ca 2+ gates and agonists of SERCA and wherein at least one of said drugs is an effective elevator of cGMP levels including activators of particulate guanylate cyclases and inhibitors of cGMP phosphodiesterases.
[0009] In one embodiment at least one of said drugs is a calmodulin (CAM) antagonist, including antagonists of the CAM targets calcineurin/protein phosphatase 2B (e.g. members of the class but not limited to cyclosporine A or the cell permeable calcineurin autoinhibitory domain poly-arginine-based polypeptide) and CAM-dependent protein kinase II (for example, members of the class but not limited to KN-62) and wherein at least one of said drugs is a Protein Kinase C (PKC) agonist (e.g. members of the class but not limited to ceramide C6).
[0010] In one embodiment at least one of said drugs is a protein kinase C agonist and wherein at least one of said drugs is an inhibitor of cGMP phosphodiesterases.
[0011] In one embodiment, at least one of said drugs is a protein kinase C agonist and wherein two additional drugs of the classes CAM-dependent protein kinase II antagonists and calcineurin/protein phosphatase 2B antagonists are combined, each at submaximal effective drug concentrations.
[0012] In one embodiment at least one of said drugs is a CAM-dependent protein kinase II antagonist and wherein at least one of said drugs is a calcineurin/protein phosphatase 2B antagonist. In one embodiment at least one of the drugs is a submaximal concentration. In one embodiment, all of the drugs are at submaximal concentration.
[0013] In one embodiment at least one of said drugs is a DNA damaging agent. In one embodiment at least one of said drugs is an anti-mitotic drug.
[0014] The disclosure teaches a method of treating a tumor in a patient comprising administering to said patient effective amounts of two or more drugs that stimulate mitochondrial Ca 2+ loading. In one embodiment further comprising administering to said patient an effective amount of a DNA damaging agent. In one embodiment further comprising administering to said patient an effective amount of an anti-mitotic drug.
[0015] The disclosure teaches a method for treating a cancer in a patient comprising administering to said patient effective amounts of two or more drugs at concentrations which interact synergistically, that stimulate an increase in the Ca 2+ burden of smooth endoplasmic reticulum and mitochondria, wherein the drugs comprise W-7 and C 6 C. In one embodiment wherein the drugs comprise PMA and W-7. In one embodiment the drugs comprise SKi and W-7. In one embodiment the drugs comprise a PP2B Antagonist and C 6 C. In one embodiment the drugs comprise (AIP) PP2B Antagonist and C 6 C. In one embodiment the drugs comprise Cyclosporin and C 6 C. In one embodiment wherein the drugs comprise an Akt/Protein Kinase B Antagonist and C 6 C. In one embodiment wherein the drugs comprise calcium, vitamin D and IP 6 .
[0016] The disclosure teaches any of the methods listed above further comprising the drug DCA.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 . Regulatory enzymatic tetrad controlling calcium targets and calcium distribution required for transitions between two sequential cell cycle phases.
[0018] FIG. 2 . Time Course of Effect of the Calmodulin Antagonist W-7 on Induction of Apoptosis in MEL-STR Cells.
[0019] FIG. 3 . Dose Response Comparison of the Effect of W-7 on Induction of Apoptosis in Malignant MEL-STR and Non-Malignant MEL-STVP Cells.
[0020] FIG. 4 . Dose Response Comparison of the Effect of the PP2A and PKC Agonist C 6 C on Induction of Apoptosis in Malignant MEL-STR and Non-Malignant MEL-STVP Cells.
[0021] FIG. 5 . Potentiation Between C 6 C and W-7 on Induction of Apoptosis in Malignant MEL-STR Cells.
[0022] FIG. 6 . Potentiation between the PKC Agonist PMA and W-7 on Induction of Apoptosis, Growth Inhibition, and Microscopic or FACS Morphology in Malignant MEL-STR Cells.
[0023] FIG. 7 . Potentiation between a Sphingosine Kinase Antagonist, SKi (4-[[4-(4-Chlorophenyl)-1,3-thiazol-2-yl]amino]phenol), and W-7 on Induction of Apoptosis in Malignant MEL-STR Cells.
[0024] FIG. 8 . Selective Potentiation of Apoptosis between the Cell Permeable Auto-Inhibitory Peptide (AIP) PP2B Antagonist and C 6 C in Malignant MEL-STR but Not Non-Malignant MEL-STVP Cells.
[0025] FIG. 9 . Potentiation of Apoptosis by the PP2B Antagonist Cyclosporin by C 6 C in Malignant MEL-STR Cells as Measured by Inhibition of Population Doubling Time.
[0026] FIG. 10 . Potentiation of Apoptosis and Inhibition of Growth Rate using an Akt/Protein Kinase B Antagonist (Triciribine) in Combination with C 6 C in Malignant MEL-STR Cells.
[0027] FIG. 11 . Prophetic Example in a Patient Diagnosed with Prostate Cancer and Subjected to a Treatment Regimen Designed to Produce Endoplasmic Reticulum Calcium Overload Using an Over-The-Counter 3 Component Mixture of Agents.
[0028] FIG. 12 . Prophetic Example in a Patient Diagnosed with Inoperable Metastasized Pancreatic Cancer with a 6 Month Survival Estimate and Subjected to a Treatment Regimen Designed to Produce Endoplasmic Reticulum Calcium Overload Using an Over-The-Counter 3 Component Mixture of Agents.
[0029] In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the described embodiments. It will be apparent to one skilled in the art, however, that other embodiments of the present invention may be practiced without some of these specific details. Several embodiments are described herein, and while various features are ascribed to different embodiments, it should be appreciated that the features described with respect to one embodiment may be incorporated with other embodiments as well. By the same token, however, no single feature or features of any described embodiment should be considered essential to every embodiment of the invention, as other embodiments of the invention may omit such features.
DETAILED DESCRIPTION
[0030] Unless otherwise indicated, all numbers used herein to express quantities, dimensions, and so forth used should be understood as being modified in all instances by the term “about.” In this application, the use of the singular includes the plural unless specifically stated otherwise, and use of the terms “and” and “or” means “and/or” unless otherwise indicated. Moreover, the use of the term “including,” as well as other forms, such as “includes” and “included,” should be considered non-exclusive. Also, terms such as “element” or “component” encompass both elements and components comprising one unit and elements and components that comprise more than one unit, unless specifically stated otherwise.
[0031] Submaximal concentration is defined as a concentration of a drug that is at least 50% lower than the concentration given for the drugs maximal effect when given alone. The concentration may be 10 fold lower than its maximal effect when given alone.
[0032] Drugs that are SERCA agonists (stimulate) include but are not limited to: Ceramide, C2-Ceramide, C6-Ceramide, HK654, PMA, and functional equivalents thereof (see Table 1, Protein Kinase C Agonists).
[0033] Drugs that are inhibitors/antagonists of SER IP3-sensitive Ca 2+ gates include but are not limited to: IP6, IP5, and functional equivalents thereof (see Table 3, Endoplasmic Reticulum Ca 2+ Overload—IP3-Receptor Antagonists).
[0034] Drugs that are agonists (activators/stimulators) of particulate guanylate cyclases include but are not limited to: Ceramide, C2-Ceramide, C6-Ceramide, HK654, PMA, and functional equivalents thereof (see Table 1, Protein Kinase C Agonists)
[0035] Drugs that are effective elevators of cGMP levels include but are not limited to: Ceramide, C2-Ceramide, HK654, PMA, and functional equivalents thereof (see Table 1, Protein Kinase C Agonists).
[0036] Drugs that are inhibitors of cGMP phosphodiesterases include but are not limited to: Viagra, Clalis, Levitra, Sulindac (and derivatives), and functional equivalents thereof (See Table 2, Endoplasmic Reticulum Ca2+Overload—cGMP PDE Antagonists).
[0037] Drugs that are calmodulin (CAM) antagonists include but are not limited to: W-7 and functional equivalents thereof (See Table 1, Calmodulin Antagonists).
[0038] Drugs that are Protein Kinase C (PKC) agonists include but are not limited to: Ceramide, C2-Ceramide, C6-Ceramide, HK654, PMA and functional equivalents thereof (see Table 1, Protein Kinase C Agonists).
[0039] Drugs that are Protein Phosphatase 2A agonists include but are not limited to: Ceramide, C2-Ceramide, C6-Ceramide, and functional equivalents thereof (see Table 1, Protein Phosphatase 2A Agonists).
[0040] Drugs that are CAM-dependent protein kinase II antagonists include but are not limited to: CK59, KN-93, KN-62, and functional equivalents thereof (see Table 1, Calmodulin-dep. Protein Kinase—II Antagonists).
[0041] Drugs that are Calcineurin/CAM-dependent protein phosphatase 2B antagonists include but are not limited to: CN585, Cell Permeable Calcineurin Autoinhibitory Peptide, Cyclosporin A, FK-506, and functional equivalents thereof (see Table 1, Calmodulin-dep. Protein Phosphatase 2B Antagonists).
[0042] Drugs that are Warburg Metabolic Antagonists include but are not limited to: Various salts of DCA, and functional equivalents thereof (see Table 3, Warburg Metabolic Antagonists).
[0043] Drugs that are DNA damaging agents include but are not limited to: Ara-C I[Cytosine β-D-arabinofuranoside] and functional equivalents thereof.
[0044] Drugs that are anti-mitotic drugs include but are not limited to: Vinblastine. [dimethyl (2β,3β,4β,5α,12β,19α)-15-[(5S,9S)-5-ethyl-5-hydroxy-9-(methoxycarbonyl)-1,4,5,6,7,8,9,10-octahydro-2H-3,7-methanoazacycloundecino[5,4-b]indol-9-yl]-3-hydroxy-[6-methoxy-1-methyl-6,7-didehydroaspidospermidine-3,4-dicarboxylate] and functional equivalents thereof.
[0045] The disclosure teaches regulation of cell cycle traverse involved a series of alternating switches consisting of elevated cGMP, Ca 2+ uptake and sequestration within the ER, and reduced cytosolic [Ca 2+ ]. These phases are followed by periods of elevated cAMP, release of ER Ca2+ increased cytosolic [Ca 2+ ], and net Ca2+ efflux from the cell. Some of these switches correlate with known cell cycle transitions. The correlated cell cycle phenomena include the relationships between the Cyclin Kinase and calcium regulatory systems. Cytosolic [Ca 2+ ] is measured in synchronized cells and is in agreement, quantitatively and temporally. The relationships between calcium, cyclic nucleotides, Cyclin Kinases, and checkpoint control systems, are used for the treatment of cancer.
[0046] The disclosure teaches uses for predicting new avenues for treating malignancy and it has been tested experimentally with positive results. The disclosure teaches an approach that is generalizable in many cancers, as it is based on one fundamental cell cycle aberration common to most if not every form of cancer. Cancers include but are not limited to melanoma, prostate, pancreatic, breast, lymphoma, lung, colon, etc.
[0047] The Warburg effect is a metabolic “defect” in energy utilization exhibited by most cancer cells. This so-called “defect” results from a change in mitochondrial function. This disclosure teaches that this “defect” is not really a defect at all but rather is a normal process that is shared by other very rapidly growing cell such as early embryonic cells. This disclosure teaches that malignant cells merely co-opt an existing system which somehow is consistent with or enables rapid proliferation.
[0048] Many different mutations in initial growth factor dependent pathways function to produce a state in which cells are made capable of continuously passing the so-called Pardee Restriction Point or point of no return towards the end of the G1 phase of the cell cycle. Traversal through G1 prior to this point is dependent on the continuous availability of EC Ca 2+ . Any growth factor requirement for passing the RP is bypassed completely by Ca 2+ specific ionophores as long as there is a ready supply of EC Ca 2+ Carcinogenic Phorbol analogs, which act to stimulate certain forms of Ca 2+ dependent PKC, can replace the growth factor requirement for crossing the RP, as long as there is sufficient EC Ca 2+ present in the growth medium. This disclosure teaches that for a normal cell to become irreversibly committed to pass through the cell cycle, these steps are effectively bypassed by providing a ready supply of EC Ca 2+ consistent with the known requirement for IC but not EC Ca 2+ upon passing the RP. Malignant transformation mimics the effect of Ca 2+ ionophores and Phorbol compounds and the initiating event in cancer is any mutation which produces an increased new steady state of continuous Ca 2+ influx. In order for such cells to escape Ca 2+ induced apoptosis, several adaptations in IC Ca 2+ -handling occur if such a potentially cancerous cell is to survive to a detectable disease state. This does not exclude the influence of known mutations in tumor suppressor or tumor promoter genes either prior to or selected for once the initiating stimulus for malignancy occurs in exacerbating the malignant state. However, all of such mutations must be secondary to satisfying the Ca 2+ requirement for passing the RP.
[0049] This disclosure teaches the anticancer mechanism of Vit D3 is through short term elevation of Ca 2+ availability through intestinal absorption and short increase in Ca 2+ uptake by cancer cells. Suppression of and lower incidence of cancer occurrence requires only a slight increase in Ca 2+ overload in malignant cells. The efficacy of Vitamin D plus Ca 2+ supplements are potentiated by drugs designed to reduce release of Ca2+ from the ER. In one embodiment, the drug would be an antagonist of the ER IP3 receptor.
[0050] Cell cycle checkpoints occur during periods of Ca 2+ sequestration and elevated cGMP levels. Cells can be prevented from passing out of these phases either directly or indirectly. Prolonged exposure to Ca 2+ influx triggers apoptosis significantly more easily in cancer cells compared to normal cells. Once normal cells pass the Pardee RP, they can complete one pass through the cell cycle in the absence of external growth factors. Only the intrinsic apoptotic pathway is used to trigger apoptosis in the event of uncorrectable genetic and chromosomal errors, as governed by cell cycle checkpoints. This pathway converges on the mitochondrion and involves Ca 2+ The mitochondrial Ca 2+ uptake pathway normally requires facilitated transfer of Ca 2+ directly from the ER as opposed to some cell-wide increase in Ca 2+ This disclosure teaches the use of drugs which shift the equilibrium from ER Ca 2+ release to ER Ca 2+ uptake. This disclosure teaches 2 (or more)-drug combinations directed against a tetrad of specific enzymes to achieve synergistic interactions and lower the possibility of unwanted side effects. Non limiting examples of drugs are found in Table 1, 2 and 3. This tetrad and the mediators of Ca 2+ distribution into and out of various compartments is illustrated in FIG. 1 .
[0051] Three main cell cycle checkpoints coincide with Ca 2+ storage phases. The Warburg phenomenon is related to changes in mitochondrial Ca 2+ content. Preventing cells from passing out of the Ca 2+ storage phases leads to mitochondrial Ca 2+ overload and subsequent apoptosis. The Ca 2+ regulatory enzyme tetrad is a means of not only controlling exit from Ca 2+ storage phases but also towards a method for converting cells residing in the Ca 2+ release phases to a state of continuous Ca 2+ storage and ultimate apoptosis. This predicts how cancer cells can be forced to undergo apoptosis by pharmaceutical intervention of Calmodulin- and PKC/PP2A-dependent processes.
[0052] Three major “Checkpoints” have been identified which, in the face of uncorrectable errors in DNA integrity (including proper chromosomal separation at anaphase), arrest cell cycle progression and lead to apoptosis. The timing of these three Checkpoints coincides with cell cycle phases during which EC Ca 2+ is sequestered within the ER. A fourth checkpoint is known to occur during G2 but only leads to a slowing of cell cycle traverse rather than apoptosis and does not coincide with Ca 2+ sequestration.
[0053] The intrinsic apoptosis pathway which operates during the cell cycle depends on the transference of Ca 2+ into the ER and ultimately into the mitochondria.
[0054] Progression of cells through the cell cycle is dependent on the ordered synthesis of specific Cyclins and activation of their partnering kinases. Likewise, cell cycle progression is also obligatorily dependent on activation of specific Ca 2+ -sensitive intracellular receptors such as Calmodulin and Ca 2+ -sensitive forms of Protein Kinase C. Errors in the operation of either of these two regulatory systems have the power to arrest cells at specific transition points in the cell cycle. These two systems function in an obligatorily inter-related manner.
[0055] Cancer cells differ from normal cells in their Ca 2+ handling. If cells could be pharmacologically arrested in Ca 2+ sequestering phases by interfering with Ca 2+ dependent mechanisms necessary to transition out of these phases, it triggers apoptosis. The extra burden of sequestered Ca 2+ in cancer cells allows for the selective induction of apoptosis in cancer cells before harming non-malignant cells. The present disclosure teaches the selective induction of apoptosis of cancer cells with reduction of toxic side-effects using novel 2 (or more)-drug combinations which are mutually synergistic.
[0056] FIG. 1 . shows the Regulatory Enzymatic Tetrad Controlling Calcium Targets and Calcium Distribution in Two Different, Contiguous Cell Cycle Phases. Abbreviations used: CAM-PP2B, Calmodulin-Dependent Protein Phosphatase 2B; CAM-PKII, Calmodulin-Dependent Protein Kinase Type II; PKC, Protein Kinase C (Ca 2+ -stimulated subtypes); PP2A, Protein Phosphatase 2A; cAMP, Cyclic Adenosine Monophosphate; PKA, Cyclic AMP-Dependent Protein Kinase; cGMP, Cyclic Guanosine Monophosphate; PKG, Cyclic GMP-Dependent Protein Kinase; SOCE, Store Operated Calcium Entry; STIM 1, Stromal Interaction Molecule 1; PMCA, Plasma Membrane Calcium ATPase; PM Ca2+ Gates (also known as CRAC or ORAI), Ca 2+ specific plasma membrane influx channels; CICR, Calcium-Induced Calcium Release; IP 3 —R, Inositol Triphosphate Receptor; RY-R, Ryanodone Receptor; SERCA-A/B, Smooth Endoplasmic Reticulum Calcium ATPase.
[0057] This illustration summarizes the cellular targets which regulate Ca 2+ distribution between various compartments as cells pass from one phase or regulatory switch-point to the next during the cell cycle. Each of the Tetrad enzymes acting directly, or secondarily through cyclic nucleotide dependent protein kinases, exert highly coordinated regulation of the functional activity of targets that control movement of Ca 2+ between cellular compartments and in and out of the cell. Of the various targets regulating Ca 2+ movements, some are activated and some are inactivated by phosphorylation. In each case, cells proceed from one switch point to the next. These phosphorylation events are reversed by opposing phosphatases. Thus, CAM-PKII is opposed by PP2A and PKC is opposed by PP2B. Steady state levels of cytosolic Ca 2+ vary between high and low levels for the entire length of each particular phase. These switch-points obligatorily control whether a cell will successfully transition from one phase to the next and successfully proceed through that phase. Pairs of contiguous phases are characterized by net Ca 2+ uptake, sequestration of said Ca 2+ into the SER compartment, and concomitant lowering of cytosolic Ca 2+ below the CAM activation threshold ([Ca 2+ ]<0.1 M). The following phase is characterized by release of sequestered Ca 2+ into the cytosol in coordination with activation of the PMCA efflux pump exactly balanced to elevate cytosolic [Ca 2+ ] above the CAM activation threshold and below the PKC activation range (>0.1 uM<1.0 uM) and to gradually reduce SER-sequestered and total cellular Ca 2+ over time.
[0058] By pharmacologically manipulating the activity of the Tetrad enzymes by appropriate stimulation or inhibition, progression through the cell cycle is arrested and all cells in the population are forced into a state of continuous Ca 2+ accumulation. Ultimately this leads to SER and mitochondrial Ca 2+ overload and triggering of apoptosis. Pharmacological manipulation of any pair of the Tetrad enzymes will interact synergistically to trigger an apoptotic response and thus can be used to reduce drug concentrations and toxicity clinically as well as shortening treatment duration. Apoptotic sensitivity of malignant cells to such treatments will be significantly greater than normal cells as a result of a greater burden of sequestered SER and mitochondrial Ca 2+ in cancer cells.
[0059] In each of the treatment methods provided, there is a therapeutic window for selectively initiating an Apoptotic cascade in tumor cells without simultaneously inducing undesirable side effects in normal Ca 2+ -dependent physiological processes of normal cells. This treatment window can easily be determined by the routine experimentation of one skilled in the art. While inhibitors of plasma membrane efflux pumps may provide some clinical efficacy, employing submaximal combinations of drugs that interact synergistically to increase cellular Ca 2+ loading provides an unexpected means to reduce undesirable side effects and to increase therapeutic indices.
[0060] The duration of treatment required to initiate an Apoptotic response in patients is relatively brief, on the order of 8 to 16 hours. In one embodiment, on the order of 3 to 6 hours. In one embodiment, 2 to 20 hours. In one embodiment, 4 to 6 hours. In one embodiment, 5 to 7 hours. Individual drugs or drug combinations are administered by standard means according to the absorptive and pharmacokinetic requirements of efficacious drug candidates. The therapeutic agents are administered orally or intravenously in amounts calculated to achieve measured blood concentrations approximating those determined to be effective from tissue culture studies. Each drug is used at the lowest dosage shown to produce mutual potentiation of apoptosis. In one embodiment, submaximal concentrations are used.
[0061] The dosage of each drug is calculated to provide clinically effective blood levels for a period of 3 to 5 hours based on animal and Phase I trials. This short duration of treatment is based upon the minimum time required to force tumor cells into irreversible commitment to apoptosis. Resorption of a patient's tumor can be followed at appropriate intervals thereafter using ultra-sensitive techniques such as PET or SPECT molecular imaging. This regimen can be repeated daily if required based upon the severity, if any, of side-effects and by the rate of tumor shrinkage. Given the thresholds of sensitivity to calcium-induced apoptosis between normal and cancerous cells, such side-effects are likely to be fairly innocuous.
[0062] Blood levels of given therapeutic agents are monitored by suitable assay methods specifically developed for this purpose in order to maximize therapeutic ratios. Depending on the severity of any side effects, this treatment regimen is repeated at regular intervals as often as necessary to maximize tumor regression. In one embodiment, drug responsiveness and treatment efficacy are monitored during the course of drug administration by assay of blood levels apoptotic markers, namely any of several caspases released by cells undergoing Apoptosis specifically developed for this purpose. In this way, patients are spared unnecessarily prolonged drug exposure and the clinician is furnished with immediate evidence of treatment efficacy.
[0063] Tables 1, 2 and 3 list drugs for the synergistic effects as described above.
[0000]
TABLE 1
PRIMARY APOPTOTIC TARGETS
TABLE 1 - PRIMARY APOPTOTIC TARGETS
PRIMARY ENZYME TETRAD
DRUG/CHEMICAL
DRUG/CHEMICAL
TARGETS
COMMON NAME
CHEMICAL NAME
Calmodulin-dep. Protein Kinase -
CK59
2-(2-Hydroxyethylamino)-6-aminohexylcarbamic acid tert-
II Antagonists
butyl ester-9-isopropylpurine
KN-93
2-[N-(2-hydroxyethyl)]-N-(4-methoxybenzenesulfonyl)]amino-
N-(4-chlorocinnamyl)-N-methylbenzylamine)
KN-62
1-[N,O-bis-(5-Isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-
phenylpiperazine
Calmodulin-dep, Protein
CN585
6-(3,4-dichloro-phenyl)-4-(N,N-dimethylaminoethylthio)-2-
Phosphatase 2B Antagonists
phenyl-pyrimidine
Calcineurin Autoinhibitory
11R-CaN-AlD, Ac-
Peptide, Cell-permeable
RRRRRRRRRRRGGGRMAPPRRDAMPSDA-NH 2
Cyclosporin A,
{R—[R*,R*—(E)]}-cyclic-(L-alanyl-D-alanyl-N-methyl-L-leucyl-
Tolypocladium inflatum
N-methyl-L-leucyl-Nmethyl-L-valyl-3-hydroxy-N,4-dimethyl-L-
2-amino-6-octenoyl-L-α-amino-butyric-N-methyl-glycinyl-
Nmethyl-L-leucyl-L-valyl-N-methyl-leucyl)
FK-506, Streptomyces
(3S,4R,5S,8R,9E,12S,14S,15R,16S,18R,19R,26aS)-
sp.
5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a
Hexadecahydro-5,19-dihydroxy-3-[(1E)-2--[(1R,3R,4R)-4-
hydroxy-3-methoxycyclohexyl]-1-methylethenyl]-14,16-
dimethoxy-4,10,12,18-tetramethyl-8-(2-propen-1-yl)-15,19-
epoxy-3H-pyrido[2,1-c][1,4]oxaazacyclotricosine-
1,7,20,21(4H,23H) tetrone
Calmodulin Antagonists
W-7
N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide
hydrochloride
Protein Phosphatase 2A
Ceramide
D-erythro-Sphingosine
Agonists
C2-Ceramide
N-Acetyl-D-sphingosine
C6-Ceramide
N-Hexanoyl-D-erythro-Sphingosine
Protein Kinase C Agonists
Ceramide
D-erythro-Sphingosine
C2-Ceramide
N-Acetyl-D-sphingosine
C6-Ceramide
N-Hexanoyl-D-erythro-Sphingosine
HK654
Diacylglycerol-lactone analog (cell permeable)
PMA
Phorbol-12-Myristate-13-Acetate
[0000]
TABLE 2
SECONDARY APOPTOTIC TARGETS
TABLE 2 - SECONDARY APOPTOTIC TARGETS
SECONDARY APOPTOTIC
DRUG/CHEMICAL
DRUG/CHEMICAL
TARGET
COMMON NAME
CHEMICAL NAME
Endoplasmic Reticulum
Ski, Ski-2
4-[[4-(4-Chlorophenyl)-1,3-thiazol-2-yl]amino]phenol
Ca2 + Overload -
Sphingosine Kinase Antagonist
Endoplasmic Reticulum
Triciribine
6-amino-4-methyl-8-(beta.-D-ribofuranosyl) pyrrolo
Ca2 + Overload -
[4,3,2-de]pyrimido[4,5-c]pyridazine
Akt/Protein Kinase B Antagonist
Endoplasmic Reticulum
Viagra
1-[4-ethoxy-3-(6,7-dihydro-1-methyl-
Ca2 + Overload -
7-oxo-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-5-yl)
cGMP PDE Antagonists
phenylsulfonyl]-4-methylpiperazine
Cialis
(6R-trans)-6-(1,3-benzodioxol-5-yl)-2,3,6,7,12,12a-
hexahydro-2-methyl-pyrazino [1′,2′:1,6] pyrido[3,4-b]
indole-1,4-dione
Levitra
4-[2-Ethoxy-5-(4-ethylpiperazin-1-yl)sulfonyl-phenyl]-9-
methyl-7-propyl-3,5,6,8-tetrazabicyclo[4.3.0]nona-3,7,9-
trien-2-one
Sulindac and
{(1Z)-5-fluoro-2-methyl-1-[4-(methylsulfinyl)
Derivatives
benzylidene]-1H-indene-3-yl}acetic acid
[0000] TABLE 3 SECONDARY APOPTOTIC TARGETS - Over-the-Counter Supplements TABLE 3 - SECONDARY APOPTOTIC TARGETS - Over-the-Counter Supplements SECONDARY APOPTOTIC DRUG/CHEMICAL DRUG/CHEMICAL TARGET COMMON NAME CHEMICAL NAME Endoplasmic Reticulum IP6, IP5 Inositol-1,2,3,4,5,6-hexakisphosphate (Inositol Cal ++ Overload - Hexaphosphate), myo-Inositol 1,3,4,5,6- IP 3 -Receptor Antagonists pentakisphosphate, (Inositol Pentaphosphate) Endoplasmic Reticulum Ca ++ Calcium Citrate Ca ++ Overload - Vitamin D3 Cholecalciferol Plasma Membrane Ca ++ Channel Agonists Warburg Metabolic Antagonists DCA Sodium di-chloro-acetate
In as much as DCA reverses the Warburg effect and thus changes the sensitivity threshold for Ca 2+ dependent release of mitochondrial cytochrome C into the cytoplasm and consequent activation of caspase apoptotic mediators, this compound is claimed to be usable to potentiate the actions of either IP6 or Ca 2+ plus Vitamin D3 either alone or in various combinations. This allows the use of DCA clinically at sub-toxic levels as well as shortening treatment duration for effective induction of apoptosis in malignant cells.
EXAMPLES
[0064] The following examples are provided for illustrative purposes only and are not intended to limit the scope of the invention.
Example 1
[0065] FIG. 2 . Shows the Time Course of Effect of the Calmodulin Antagonist W-7 on Induction of Apoptosis in MEL-STR Cells. Malignant (MEL-STR) and non-malignant (MEL-STVP) cells used in these experiments were derived originally from normal human foreskin melanocytes obtained from the Weisberg lab. These original surgical samples were genetically modified to grow continuously in vitro and are non-tumor-forming in a nude mouse model. These same cells were genetically modified further to generate the tumor-forming cell line and were propagated. Thus, this represents an ideal pair of highly similar cells by which drug specificity between normal and malignant cells can be assessed.
[0066] Transformed MEL-STR cells were incubated over a period of 24 hrs in the presence of a previously determined ineffective concentration (10 μm) of the CAM antagonist W-7 or the drug vehicle DMSO (1%) as controls and a concentration of 60 μm W-7 as illustrated. Apoptotic+dead cells were assayed in this experiment and those that follow below on a Becton-Dickenson flow cytometer using an Annexin V-FITC Apoptosis Detection Kit as described by the manufacturer.
[0067] The results in this experiment show the time course for induction of apoptosis in the malignant cell line (measured by the Annexin Assay) by a highly-specific antagonist of the primary intracellular Ca 2+ receptor, Calmodulin. Calmodulin is known to be required for traverse of late G1, G2, and specific periods during mitosis and coincides with periods of elevated cAMP levels. Surprisingly, induction of apoptosis can be seen as soon as 3 hours of drug exposure. Morphological rounding of cells can be observed microscopically of by changes in FACS light scatter as early as 1 hrs. This is to be compared with typical studies on drug-induced apoptosis which require 48-72 hrs. of exposure. This is especially important because patient exposure and unwanted side-effects can be minimized in vivo. Essentially all of the population (at least in excess of 90%) scores positively for apoptosis. Given the ubiquitous function of Calmodulin in every cell of the body, use of the drug (or more potent congeners) has not been previously used for development by the pharmaceutical industry as far too toxic for clinical use.
Example 2
[0068] FIG. 3 show a Dose Response Comparison of the Effect of W-7 on Induction of Apoptosis in Malignant MEL-STR and Non-Malignant MEL-STVP Cells. These results are critically important and highly unusual. Transformed malignant cells are more sensitive than non-transformed cells to a completely specific drug which acts only to antagonize a single target, that is, the main IC calcium receptor Calmodulin. The degree of this difference in sensitivity is approximately one order of magnitude. This is large enough that allows the use W-7 clinically. However, Calmodulin regulates many processes throughout the body and despite this sensitivity advantage may still trigger unwanted side effects.
Example 3
[0069] FIG. 4 shows a Dose Response Comparison of the Effect of the PP2A and PKC Agonist C 6 C on Induction of Apoptosis in Malignant MEL-STR and Non-Malignant MEL-STVP Cells. The sensitivity difference observed in FIG. 3 is not unique to the Calmodulin antagonist W-7 and a similar order of magnitude in EC50's is observed using a drug originally thought to stimulate specific PKC and PP2A targets at the time these experiments were carried out. This drug is now thought to act specifically on PP2A alone. These results show that malignant cells exhibit a very significant difference from normal cells in triggering Apoptosis and teach that cancer cells survive by reaching a stable condition of Ca 2+ overload higher than non-malignant cells.
Example 4
[0070] FIG. 7 shows Potentiation Between C 6 C and W-7 on Induction of Apoptosis in Malignant MEL-STR Cells. In this experiment, it is shown that when combined with the Calmodulin antagonist (W-7) the effects of this drug on induction of Apoptosis are potentiated. Given the accepted specificity of W-7, this experiment provides evidence that both drugs are affecting processes that share Ca 2+ in common.
Example 5
[0071] FIG. 9 shows Potentiation between the PKC Agonist PMA and W-7 on Induction of Apoptosis, Growth Inhibition, and Microscopic or FACS Morphology in Malignant MEL-STR Cells. The involvement of a form of PKC in the enzyme tetrad that is involved in Ca 2+ -dependent, cell cycle phase transitions is given in FIG. 6 . Here the classic PKC activator, Phorbol Myristate Acetate, is found to be potentiated by W-7. Four different means for assaying the effect of these two chemicals are shown. The standard Annexin assay for detecting Apoptosis shows potentiation (Panel A). However, the more sensitive cell density assay as measured by Coulter Counter shows an even greater potentiation (Panel B). Potentiation is also confirmed by two different measures of cell shape, Light scatter by FACS (Panel C) and by direct microscopic examination (Panel D; results shown are the average of 3 microscope fields selected at random). Throughout all of the results reported here, the morphological effect can be observed as early as 1 hr. drug exposure and has been a sensitive indicator of the subsequent apoptotic fate of the MEL-STR cells under study. It is significant that such morphological shape changes are not observed in MEL-STVP cells. It is also important to realize that the only element in common with PMA and W-7 is Ca 2+ and these results provide additional evidence supporting the enzymatic tetrad regulatory system in triggering apoptosis.
Example 6
[0072] FIG. 8 shows Potentiation between a Sphingosine Kinase Antagonist, SKi (4-[[4-(4-Chlorophenyl)-1,3-thiazol-2-yl]amino]phenol), and W-7 on Induction of Apoptosis in Malignant MEL-STR Cells. This result is especially interesting because it provides evidence that Ca 2+ must be involved in the action of Sphingosine Kinase. Given the widespread distribution of this enzyme in normal cells, and given the 10-fold potency advantage over non-malignant MEL-STVP cells enjoyed by W-7 (see FIG. 1 ), these results represent another method for toxicity reduction during cancer therapy and a way of using a drug like W-7 that normally would be expected to be too toxic for use clinically. The synergy between W-7 and SKi provides evidence that both are converging upon a common element, namely Ca 2+ .
Example 7
[0073] FIG. 5 is Selective Potentiation of Apoptosis between the Cell Permeable Auto-Inhibitory Peptide (AIP) PP2B Antagonist and C 6 C in Malignant MEL-STR but Not Non-Malignant MEL-STVP Cells. These results illustrate potentiation between C6C and a completely specific activator of the Calmodulin plus Ca 2+ requiring enzyme PP2B which is a cell-permeable auto-inhibitory polypeptide (abbr. PP2B-AIP) which acts to block the catalytic site of PP2B. Four observations can be drawn from these results. The first and foremost is that this result was predicted as a consequence of the Calcium Storage/Release Model in 2002. The synergistic interaction with C6C provides yet another example of convergence of two highly dissimilar targets which share Ca 2+ in common. This potentiation is seen only in the transformed MEL-STR cell line, not in untransformed MEL-STVP cells, thus providing a third example of differential sensitivity between malignant and non-malignant cells. Lastly, over the concentration range tested, AIP exerted no visible induction of apoptosis in either cell line.
[0074] In this and other experiments using this protocol, it has never been possible to kill more than 50% of the MEL-STR cells over a 5 hr. exposure. This is in marked contrast to the potent effect of W-7 ( FIG. 2 ). This implicates at least one other target involved in the actions of W-7. This target is likely to be Calmodulin-dependent Protein Kinase II. This enzyme completes the 4 th element of the regulatory enzymatic tetrad as illustrated in FIG. 1 . Thus, pharmacological (antagonists of Calmodulin effectors, PP2B and PCAM-PK II; agonists of PKC and PP2A) manipulation any pair of tetrad enzymes is expected to interact synergistically and be usable in clinical practice.
Example 8
[0075] FIG. 6 shows Potentiation of Apoptosis by the PP2B Antagonist Cyclosporin by C 6 C in Malignant MEL-STR Cells as Measured by Inhibition of Population Doubling Time. As a test of the specificity of AIP, the effect of Cyclosporin (a known inhibitor of PP2B) was tested for pro-apoptotic potential. At quite high concentrations, this compound displayed only slight stimulation of apoptosis or growth inhibition measured in this experiment by a change in doubling time (an indirect assay of cell death). This effect was dramatically potentiated by C6C in MEL-STP cells in the same manner as the previous experiment with AIP ( FIG. 7 ). In MEL-STVP cells, no inhibition of cell growth was observed with Cyclosporin at this or lower concentrations nor was there any potentiation observed between these two compounds, thus providing a fourth example of differential sensitivity between malignant and non-malignant cells.
Example 9
[0076] FIG. 10 shows Potentiation of Apoptosis and Inhibition of Growth Rate using an Akt/Protein Kinase B Antagonist (Triciribine) in Combination with C 6 C in Malignant MEL-STR Cells. Because PKB has pro-survival/anti-apoptotic properties and, when activated, can overcome checkpoint arrests in both G1 and G2 (periods in which cAMP is normally elevated during traverse of these phases), because cAMP has been implicated in many cells types as an anti-apoptotic agent, and because cAMP is known to stimulate the release of ER Ca 2+ the question of whether these observations shared a common mechanism involving ER Ca 2+ reduction was tested experimentally. The effect of low dose C6C on cells treated over a wide concentration range of the PKB inhibitor Triciribine was examined. The results of the highest dose of Triciribine tested are shown in FIG. 8 . Clear potentiation was observed consistent with the hypothesis that ER Ca 2+ overload can promote Apoptosis in cancer cells and that PKB antagonists could be used synergistically with other drugs which modulate cellular Ca 2+ distribution and as a means of reducing off-target side-effects.
[0077] There are other ways of effecting clinical treatment of any and all cancer cell types. For example, any treatment which delivers excess Ca 2+ to the right location within cells, even on a short term basis, could be combined with an agent that inhibits release of Ca 2+ from the ER, the obligatory organelle that transfers Ca 2+ to the mitochondria and induces an apoptotic response. Calcitriol (the active form of Vitamin D) reduces the incidence of certain cancers to a small but significant degree (ca. 17-20%). This cannot be demonstrated when only 400 IU of Vitamin D is taken as a supplement, nor can it be shown when only 1000 mg of Calcium is taken. Only when the two are combined is any effect observed, albeit quite modest. If this regimen is combined with an inhibitor of ER Ca 2+ release, such as IP6 at doses up to 1000-1600 mg/day, or in another embodiment, at 500-800 mg; taken twice daily, then together this 3-component combination synergistically interacts to produce a much larger reduction of cancer incidence as well as reducing or even eliminating established cancers. Below are two prophetic examples illustrating different forms of cancer and the responses that can be expected as measured by antigen markers.
Example 10
[0078] Since this 3-part regimen, at the levels shown, should have no detectable side effects, it may be used in conjunction with either male or female hormone replacement therapies in order to nullify any chance of elevated cancer risk associated with testosterone or estrogen supplementation.
[0079] FIG. 11 shows a Prophetic Example in a Patient Diagnosed with Prostate Cancer and Subjected to a Treatment Regimen Designed to Produce Endoplasmic Reticulum Calcium Overload Using an Over-The-Counter 3 Component Mixture of Agents. A patient is prescribed 1000 mg Calcium Citrate (or mixed salts of citrate, malate, and carbonate), 2000 IU of Vitamin D3, and 500 mg IP6 to be taken twice daily 12 hrs. apart. This regimen is continued for at least 6 months. The dose of Calcium salt and IP6 (but not Vitamin D3) can be increased to thrice daily without side effects. This treatment should be combined with adequate exposure to sunlight. Relief of symptoms can be expected within the first 2-3 weeks of treatment and the effects of this regimen can be followed objectively by standard PSA measurements as illustrated in this figure or more specific prostate cancer-specific antigens in development.
Example 10
[0080] FIG. 12 shows a Prophetic Example in a Patient Diagnosed with Inoperable Metastasized Pancreatic Cancer with a 6 Month Survival Estimate and Subjected to a Treatment Regimen Designed to Produce Endoplasmic Reticulum Calcium Overload Using an Over-The-Counter 3 Component Mixture of Agents. The same regimen as described in FIG. 11 is provided. Enlargement of metastasized tumors should be arrested and some tumors may be eliminated entirely. The effect of the treatment regime is illustrated in this figure by radioimmunoassay of the pancreatic cancer antigen CA-19-9 over time.
[0081] The description of the various embodiments has been presented for purposes of illustration and description, but is not intended to be exhaustive or limiting of the invention to the form disclosed. The scope of the present invention is limited only by the scope of the following claims. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments described and shown in the figures were chosen and described in order to explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated. All references cited herein are incorporated in their entirety by reference. | Tumor cells exhibit consistent abnormalities in calcium regulation. The present disclosure teaches methods by which such differences are exploited to induce Apoptosis selectively in tumor/cancer cells while sparing normal cells. These methods are based upon employing drugs that, acting in synergistic combinations, trigger selective killing of malignant cells. Since the invention is based upon fundamental cell cycle requirements, to the extent that calcium handling abnormalities are a general characteristic of the malignant state, the methods presented here are widely applicable regardless of tissue of origin and degree of cellular de-differentiation. | 0 |
FIELD OF THE INVENTION
The present invention generally relates to mobile terminals and more particularly to user interfaces of mobile terminals.
BACKGROUND OF THE INVENTION
Mobile terminals, or mobile (cellular) telephones, for mobile telecommunications systems like GSM, UMTS, D-AMPS and CDMA2000 have been used for many years now. In the older days, mobile terminals were used almost exclusively for voice communication with other mobile terminals or stationary telephones. More recently, the use of modern terminals has been broadened to include not just voice communication, but also various other services and applications such as www/wap browsing, video telephony, electronic messaging (e.g. SMS, MMS, email, instant messaging), digital image or video recording, FM radio, music playback, electronic games, calendar/organizer/time planner, word processing, etc. With this great number of applications, user interaction naturally becomes complex and somewhat difficult.
In the prior art, one attempt to simplify for users is to use two dimensional menus, allowing the user to see a large number of selectable applications simultaneously. However, switching from one application to the next is still a process which requires relatively focused attention by the user, even for the most common applications.
Consequently, there is a need to provide a mobile communication terminal and method providing a user interface with simpler and more intuitive selection of the most common applications.
SUMMARY
In view of the above, an objective of the invention is to solve or at least reduce the problems discussed above.
Generally, the above objectives are achieved by the attached independent patent claims.
According to a first aspect of the present invention there has been provided a method for providing a user interface of a portable electronic apparatus, the method comprising: detecting an actuation of a mode switch actuator associated with switching operational modes of the apparatus; determining a switching direction by determining whether the actuation is associated with a first switching direction or a second switching direction; determining a current operational mode; determining a new operational mode considering the switching direction and the current operational mode; and switching operational modes of the portable electronic apparatus from the current operational mode to the new operational mode. It is thus provided a way for the user to easily change operating mode of the portable electronic apparatus. This is a much simpler and quicker user operation than finding an application in a menu system.
The determining a new operational mode may involve: determining the new operational mode as a next operational mode after the currently active operational mode in a predefined circular list of operational modes when the switching direction is determined to be the first direction; and determining the new operational mode as a previous operational mode after the currently active operational mode in a predefined circular list of operational modes when the switching direction is determined to be the second direction. A circular list simplifies use of the method with a varying number of operational modes.
The current operational mode may be associated with a first main user application and the new operational mode may be associated with a second main user application.
The switching operational mode may involve presenting a user indication. The user indication emphasizes the switch of operational modes for the user.
The user indication may comprise at least one user indication selected from the group comprising a visual indication on a display of the apparatus, an audible indication and a tactile indication.
The switching operational modes may involve presenting an intermediate animation on the display before a screen for the new operational mode is displayed. An animation is effective in showing the user what is happening and can be enjoyable to watch.
The switching operational modes may involve presenting an animation on the display, the animation comprising sliding a screen for the new operational mode in from a side.
The predefined circular list of operational modes may comprise three operational modes.
The three operational modes may be a phone mode, a media player mode and a radio mode.
The switching operational modes may involve switching a backlight for keys of the portable electronic apparatus from a first configuration to a second configuration.
A second aspect of the present invention is a portable electronic apparatus having at least two operational modes comprising: a mode switch actuator and a controller, wherein: the controller is configured to detect an actuation of a user input associated with switching operational modes of the apparatus and to determine a switching direction associated with the user input; the controller is configured to determine a current operational mode being a currently active operational mode; the controller is configured to determine a new operational mode considering the switching direction; and the controller is configured to switch operational modes of the portable electronic apparatus from the current operational mode to the new operational mode in response to a detection of an actuation of the mode switch actuator.
The portable electronic apparatus may be a mobile communication terminal.
The mode switch actuator may be a slide key capable of being in a first directional position, a middle position and a second directional position, and the slide key may be biased to the middle position.
The first directional position may be associated with a first switching direction and the second directional position is associated with a second switching direction.
A third aspect of the present invention is a portable electronic apparatus having at least two operational modes comprising: a mode switch actuator; a controller; means for detecting an actuation of the mode switch actuator; means for determining a current operational mode being a currently active operational mode; means for determining a new operational mode; and means for switching operational mode of the portable electronic apparatus from the current operational mode to the new operational mode.
The portable electronic apparatus may be a mobile communication terminal.
A fourth aspect of the present invention is a computer program product comprising software instructions that, when executed in a portable electronic apparatus, performs the method according to the first aspect.
A fifth aspect of the invention is a user interface for a portable electronic apparatus having at least two operational modes, the user interface comprising: a mode switch actuator, wherein: the user interface is configured to detect an actuation of a user input associated with switching operational modes of the apparatus and to determine a switching direction associated with the user input; the user interface is configured to determine a current operational mode being a currently active operational mode; the user interface is configured to determine a new operational mode considering the switching direction; and the user interface is configured to switch operational modes of the portable electronic apparatus from the current operational mode to the new operational mode in response to a detection of an actuation of the mode switch actuator.
Other objectives, features and advantages of the present invention will appear from the following detailed disclosure, from the attached dependent claims as well as from the drawings.
Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the [element, device, component, means, step, etc]” are to be interpreted openly as referring to at least one instance of the element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described in more detail, reference being made to the enclosed drawings, in which:
FIG. 1 is a schematic illustration of a cellular telecommunication system, as an example of an environment in which the present invention may be applied.
FIG. 2 is a schematic front view illustrating a mobile terminal according to an embodiment of the present invention.
FIG. 3 is a schematic block diagram representing an internal component, software and protocol structure of the mobile terminal shown in FIG. 2 .
FIG. 4 is a schematic diagram showing how operational modes can be switched in the mobile terminal of FIG. 2 .
FIG. 5 is a flow chart illustrating the process illustrated in FIG. 4 .
DETAILED DESCRIPTION OF EMBODIMENTS
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
FIG. 1 illustrates an example of a cellular telecommunications system in which the invention may be applied. In the telecommunication system of FIG. 1 , various telecommunications services such as cellular voice calls, www/wap browsing, cellular video calls, data calls, facsimile transmissions, music transmissions, still image transmissions, video transmissions, electronic message transmissions and electronic commerce may be performed between a mobile terminal 100 according to the present invention and other devices, such as another mobile terminal 106 or a stationary telephone 132 . It is to be noted that for different embodiments of the mobile terminal 100 and in different situations, different ones of the telecommunications services referred to above may or may not be available; the invention is not limited to any particular set of services in this respect.
The mobile terminals 100 , 106 are connected to a mobile telecommunications network 110 through RF links 102 , 108 via base stations 104 , 109 . The mobile telecommunications network 110 may be in compliance with any commercially available mobile telecommunications standard, such as GSM, UMTS, D-AMPS, CDMA2000, FOMA or TD-SCDMA.
The mobile telecommunications network 110 is operatively connected to a wide area network 120 , which may be Internet or a part thereof. An Internet server 122 has a data storage 124 and is connected to the wide area network 120 , as is an Internet client computer 126 . The server 122 may host a www/wap server capable of serving www/wap content to the mobile terminal 100 .
A public switched telephone network (PSTN) 130 is connected to the mobile telecommunications network 110 in a familiar manner. Various telephone terminals, including the stationary telephone 132 , are connected to the PSTN 130 .
The mobile terminal 100 is also capable of communicating locally via a local link 101 to one or more local devices 103 . The local link can be any type of link with a limited range, such as Bluetooth, a Universal Serial Bus (USB) link, a Wireless Universal Serial Bus (WUSB) link, an IEEE 802.11 wireless local area network link, an RS-232 serial link, etc. The local devices 103 can for example be various sensors that can communicate measurement values to the mobile terminal 100 over the local link 101 .
An embodiment 200 of the mobile terminal 100 is illustrated in more detail in FIG. 2 . The mobile terminal 200 comprises a speaker or earphone 202 , a microphone 205 , a display 203 and a set of keys 204 which may include a keypad 204 a of common ITU-T type (alpha-numerical keypad representing characters “0”-“9”, “*” and “#”) and certain other keys such as soft keys 204 b , 204 c , a send-key 204 d , and an end-key 204 e . Moreover, a directional input 211 is provided, such as a joypad with a central button 211 a , a joystick or other type of navigational input device. In this embodiment, the central button 211 a functions, at least when it is applicable to a currently running application, for playing or pausing media.
A mode switch actuator 212 is also provided. The actuator is used to switch an operational mode of the mobile terminal. In this embodiment, the actuator is by default positioned in a middle position. When the user wants to switch modes, the actuator is moved to a left position or a right position and released, after which the actuator returns to the default middle position by mechanical means, such as a spring or similar. The mode switch actuator 212 could also be implemented by any type of input device capable of detecting at least two directional inputs, such as a dual spring loaded key, a touch pad, a rocker switch, any other type of bi-directional rotational device, etc.
Backlights are arranged by all keys 204 , the directional input 211 as well as by the mode switch actuator 212 .
The internal component, software and protocol structure of the mobile terminal 200 will now be described with reference to FIG. 3 . The mobile terminal has a controller 300 which is responsible for the overall operation of the mobile terminal and is preferably implemented by any commercially available CPU (“Central Processing Unit”), DSP (“Digital Signal Processor”) or any other electronic programmable logic device. The controller 300 has associated electronic memory 302 such as RAM memory, ROM memory, EEPROM memory, flash memory, hard drive, or any combination thereof. The memory 302 is used for various purposes by the controller 300 , one of them being for storing data and program instructions for various software in the mobile terminal. The software includes a real-time operating system 320 , drivers for a man-machine interface (MMI) 334 , an application handler 332 as well as various applications. The applications can include a media player application 350 , an FM radio application 360 , as well as various other applications 370 , such as applications for voice calling, video calling, sending and receiving SMS, MMS or email, web browsing, an instant messaging application, a phone book application, a calendar application, a control panel application, a camera application, one or more video games, a notepad application, etc.
The MMI 334 also includes one or more hardware controllers, which together with the MMI drivers cooperate with the display 336 / 203 , keypad 338 / 204 as well as various other I/O devices such as the mode switch key 212 , microphone 205 , speaker 202 , vibrator, ringtone generator, LED indicator, backlight, etc. As is commonly known, the user may operate the mobile terminal through the man-machine interface thus formed.
The software also includes various modules, protocol stacks, drivers, etc., which are commonly designated as 330 and which provide communication services (such as transport, network and connectivity) for an RF interface 306 , and optionally a Bluetooth interface 308 and/or an IrDA interface 310 or other suitable interfaces for local connectivity. The RF interface 306 comprises an internal or external antenna as well as appropriate radio circuitry for establishing and maintaining a wireless link to a base station (e.g. the link 102 and base station 104 in FIG. 1 ). As is well known to a man skilled in the art, the radio circuitry comprises a series of analogue and digital electronic components, together forming a radio receiver and transmitter. These components include, i.a., band pass filters, amplifiers, mixers, local oscillators, low pass filters, AD/DA converters, etc.
The mobile terminal also has a SIM card 304 and an associated reader. As is commonly known, the SIM card 304 comprises a processor as well as local work and data memory.
FIG. 4 shows how operational modes can be switched in an embodiment of the present invention. The mobile terminal 400 , such as mobile terminal 200 of FIG. 2 , comprises a display 403 , such as display 203 of FIG. 2 , a joypad 411 , such as joypad 211 of FIG. 2 , and a mode switch key 412 such as mode switch actuator 212 of FIG. 2 , to allow the user to switch operational modes.
Operational modes are modes where the mobile terminal 400 behaves in specific ways. For example, FIG. 4 shows three operational modes: a phone mode 440 , a media player mode 441 and a radio mode 442 . Each operational mode allows the mobile terminal to focus on a main user application, or functionality of that mode, allowing for predictable use. Each operational mode can change the behavior of the keypad, menu structure, idle screen, etc.
When the mobile terminal 400 is in the phone mode 440 , the mobile terminal behaves as a user would expect a regular mobile terminal to behave. In other words, a menu system and/or shortcuts allow the user to instruct the mobile terminal to perform a desired function, such as voice telephony, www/wap browsing, video telephony, electronic messaging (e.g. SMS, MMS, email, instant messaging), digital image or video recording, electronic games, calendar/organizer/time planner, word processing, etc.
When the mobile terminal 400 is in the media player mode 441 , the main purpose of the mobile terminal is to play media to the user. For example, the media player can play music or sound files, such as MP3 (mpeg-1 audio layer 3) files, AAC (advanced audio coding) files or ogg files. Optionally, the media player can also be used to play video files according to standards such as MPEG-2, MPEG-4 or H.264.
Finally, when the mobile terminal 400 is in the radio mode 442 , the main purpose of the mobile terminal is to allow the user to listen to FM radio. Optionally, favorite radio stations can be stored, and text data by means of radio data system (RDS) can be presented on the display 403 .
As the user switches operational modes with mode switch actuator 412 either to the right or to the left, the modes are switched serially, as indicated by arrows 413 a - c to the right and arrows 414 a - c to the left. In the illustrated embodiment, there is a circular list of operational modes consisting of the phone mode 440 , the media player mode 441 , and the radio mode 442 , in that order. Consequently, when the mobile terminal 400 is in the phone mode 440 and the user actuates the mode switch actuator 412 to the right, the mobile terminal switches to the media player mode 441 . On the other hand, if the user actuates the mode switch actuator 412 to the left while in the phone mode 440 , the phone switches to the radio mode 442 . Similarly, when the mobile terminal 400 is in the media player mode 441 , the mobile terminal 400 switches to the radio mode 442 if the user actuates the mode switch actuator 412 to the right, or to the phone mode 440 if the user actuates the mode switch actuator 412 to the left. Moreover, when the mobile terminal 400 is in the radio mode 442 , the mobile terminal 400 switches to the phone mode 440 if the user actuates the mode switch actuator 412 to the right, or to the media player mode 441 if the user actuates the mode switch actuator 412 to the left.
In the present embodiment, the initial states of the different operational modes when these are switched to in the present embodiment will now be described.
When the mobile terminal switches operational modes to the phone mode 440 , the state of the phone mode 440 is the same as when it was last exited. E.g. if the user was writing a text message when the phone mode 440 was last exited, the same text message entry screen is displayed when the phone mode 440 becomes active again.
When the mobile terminal switches to the media player mode 441 , a screen displaying currently playing media is displayed, regardless of the state when the media player mode 441 was last exited.
When the mobile terminal switches to the radio mode 442 , the main radio screen is always shown initially, regardless what state the radio application was in the last time it was active. In this embodiment, the user has to initiate the radio playing in the application, at which time the user is informed if there is no antenna connected. In other words, the radio does not generate any sound until the user has pressed “play” e.g. by pressing the central joypad button 211 a . If the media player is active playing audio prior to switching to the radio application, this audio keeps playing until the radio actually starts playing and generating sound.
FIG. 5 is a flow chart illustrating the process illustrated in FIG. 4 .
In a detect user input for switching step 580 , it is detected that the user has actuated a user input associated with switching operational mode.
In a determine switching direction step 582 , it is determined which direction the user input is associated with. The direction could be right, left, or even up or down.
In a determine current operational mode step 584 , it is determined what operational mode the mobile terminal is in presently.
In a determine next operational mode step 586 , the current operational mode and the direction associated with the user input are used to determine the next operational mode to switch to. More concrete examples of this step is described with reference to FIG. 4 above.
In a switch operational mode step 588 , the operational mode of the mobile terminal is switched to the previously determined next operational mode.
Various animations are possible when switching from one mode to the next. Now a number of alternative animations will be presented:
The screen for the new operational mode slides in over the current screen, optionally from the direction indicated by the user input. The screen for the new operational mode quickly replaces the current screen, after which an informational screen indicating the new operational mode slides in and out. The informational screen can contain text and/or graphics indicating the new operational mode. An informational screen indicating the new operational mode quickly replaces the current screen. A semi-transparent or solid colored bar slides over the informational screen, after which the new operational mode is displayed. An informational screen indicating the new operational mode quickly replaces the current screen. In this animation, however, the informational screen is semi-transparent such that the new operational mode can be seen behind the informational screen. A semi-transparent or solid colored bar slides over the informational screen, after which the informational screen is removed and the new operational mode becomes fully visible. A 3D animation is shown indicating a movement from the first operational mode to the second operational mode. For example, the animation can show a rotation of blocks for the different operational modes, where each block comprises text and/or graphics indicating the operational mode it is associated with. The screen for the new operational mode quickly replaces the current screen, after which a text and/or graphics item slides in and out over the screen.
Additionally, other user indications can be given when the actual mode change occurs. For example, the vibrator may vibrate on a mode change, where the vibration is either always identical for all modes or every mode has a particular vibration associated with it. Additionally, a sound effect or speech synthesizer pronouncing the new mode can be played to the user.
It is to be noted that while the modes are switched, certain appropriate processing of an inactive mode can still be performed. For example, the radio can let the user hear an FM radio station while the mobile terminal is in the phone mode, or the phone application can temporarily interrupt current processing if an incoming phone call is detected.
To allow the user to easily determine what mode is currently used, elements of the user interface are specific for each mode. There are a multitude of distinguishing user interface elements that can vary to allow the user to see what mode is currently active, e.g., a light by the joypad 211 can be on or off or optionally change color, the background on the display 403 can have different colors or appearances, or the entire theme of the user interface with colors and fonts can change.
One embodiment will now be described to illustrate an example where different states are indicated using lights by input elements of the mobile terminal.
When the mobile terminal is in the phone mode 440 and the user interface is active, there is a light by each of the keys, such as the soft keys 204 b - c , the send key 204 d , the end key 204 e and keypad 204 a . Furthermore, there is a ring of light around the joypad 211 and a backlight of the mode switch actuator 212 .
When the mobile terminal is in the phone mode 440 and the user interface is inactive (due to a certain period of user inactivity), all the backlights are turned off. This reduces the power consumption when the user is inactive.
When the mobile terminal is in the media player mode 441 or the radio mode 442 and the user interface active, there is a light by each of the keys, such as the soft keys 204 b - c , the send key 204 d , the end key 204 e and keypad 204 a . Furthermore, there is a ring of light around the joypad 211 and a backlight of the mode switch actuator 212 , just as in the active phone mode 440 . However, here also the center button 211 a of the joypad is illuminated, whereby the user can see the symbol for play/pause which is otherwise partially or completely invisible.
When the mobile terminal is in the media player mode 441 or the radio mode 442 and the user interface is inactive (due to a certain period of user inactivity), all the backlights are turned off. However, the center button 211 a of the joypad is illuminated with light pulses periodically. This reduces the power consumption when the user is inactive, while still indicating to the user the much used play/pause functionality of the center button 211 a of the joypad.
While the an embodiment of the invention is described above as embodied in a mobile terminal, the invention can be implemented in any type of portable electronic apparatus.
It is to be noted that the number and function of the operational modes mentioned above are only examples and the scope of the present invention covers any number of operational modes with any type of functionality. In one embodiment, the user may configure what main user application is associated with each operational mode, and optionally reorder the operational modes. In one embodiment, certain operational modes can be associated with specific applications selected by an operator, e.g. applications specifically developed or customized for that operator to increase operator visibility in the mobile terminal. Optionally, one of the operational modes can be fixed, such as the phone mode 440 , preventing the user from changing the function of that mode.
The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims. | It is presented a method for providing a user interface of a portable electronic apparatus. The method comprises: detecting an actuation of a mode switch actuator associated with switching operational modes of the apparatus; determining a switching direction by determining whether the actuation is associated with a first switching direction or a second switching direction; determining a current operational mode; determining a new operational mode considering the switching direction and the current operational mode; and switching operational modes of the portable electronic apparatus from the current operational mode to the new operational mode. Corresponding portable electronic apparatuses and computer program product are also presented. | 7 |
This invention was made with Government support under NIH Grant No. T32 HD07118 awarded by the Department of Health and Human Services and NSF Grant Nos. PCM 8409741 and PCM 8416415 awarded by the National Science Foundation. The Government has certain rights to this invention.
BACKGROUND OF THE INVENTION
A. Field of The Invention
The present invention relates to recombinant DNA technology. More specifically, it involves the creation of a cDNA genetric sequence coding for bovine placental lactogen, a vector containing this gene, and a host containing the cDNA gene.
B. Description Of The Art
The placenta of a cow secretes numerous endocrine signals, including bovine placental lactogen (which is evolutionarily related to growth hormone and prolactin). Naturally produced bovine placental lactogen (also known as bovine chorionic somatomammotropin) has recently been purified and characterized. (See K. A. Eakle et al, Endocrinology 110: 1758-1765 (1982); G. S. Murthy et al., Endocrinology 111: 2117-2124 (1982); and Y. Arima et al., Endocrinology 113: 2186-2194 (1983)) (the disclosure of these articles and of all other articles cited in this patent are incorporated by reference as a fully set forth below.) As described in these articles, at least one (and possibly three) forms of bovine placental lactogen exist.
Bovine placental lactogen promises to have great utility for research and other purposes. For example, it appears to relate to pregnancy development. (See generally C. Schellenberg et al., Endocrinology 111: 2125-2128 (1982) (levels change during gestation), or it may stimulate milk production (see U.S. Pat. No. 3,644,925, bovine growth hormone increases milk production.) Still other functions for this protein are likely to be discovered.
Unfortunately, commercial qualities of the protein are not available, and it is prohibitively expensive to extract the protein from natural sources. Thus, it can be seen that a need has existed for a source of large quantities of bovine placental lactogen.
SUMMARY OF THE INVENTION
The present invention relates to a cDNA gene sequence, a recombinant vector, and a recombinant host. In one embodiment, there is provided a vector and a foreign gene sequence that codes for bovine placental lactogen which is inserted into the vector. The sequence is a cDNA sequence. cDNA is the gene coding for a protein, but with intervening sequences (introns) not coding for protein deleted.
A plasmid pbPL10 having all of this cDNA coding sequence has been deposited at the American Type Culture Collection, Rockville, Md., in the recombinant host E. coli HB101, with ATCC number 53065, and will be made available upon the issuance of this patent in accordance with U.S. patent law and other such foreign patent laws as may apply. The availability of this culture is not meant as a license to use it.
In another embodiment, there is provided a cDNA genetic sequence coding for bovine placental lactogen.
In yet another embodiment, there is provided a recombinant host capable of expressing bovine placental lactogen. The host comprises a host cell, a promoter gene sequence, and a foreign gene sequence coding for bovine placental lactogen which is subjected to the promoter's control. Preferably, the host can be cultured in a nutrient medium and grown up to large qualities.
Of course, it has been known for some time that genes code for proteins. It has also been known since the early 1970's that many genes can be made to express commercial quantities of a protein if the gene can be isolated and cloned. However, it is one thing to say this, and quite another to locate the specific gene which codes for a given protein. Further, in many cases one must form a cNDA variant of the gene before one can obtain expression of the protein.
One gene which had previously defied identification and isolation was the bovine placental lactogen gene. A feature of the present invention, therefore, was the idea that if the bovine prolactin or bovine growth hormone gene happened to be sufficiently similar to bovine placental lactogen gene, hybridization techniques might be able to identify the placental lactogen cDNA. However, this idea alone was not enough. Instead, an ingenious brick-by-brick approach was required.
Hybridization techniques work on the principle that under certain conditions dissimilar (but somewhat similar) DNA strands will stick together. The applicants discovered that given sufficient similarity in sequence, prolactin cDNA will hybridize (stick) to certain portions of the lactogen DNA gene, and then similar techniques could use these DNA fragments to pick out cDNA fragments, and then these cDNA fragments could pick out the lactogen cDNA. (It turns out that bovine prolactin and growth hormone cDNA won't readily hybridize directly to lactogen cDNA.) Thus, it took a very ingenious "brick by brick" approach to isolate the full lactogen cDNA.
The objects of the invention therefore include:
(a) providing a gene sequence that expresses bovine placental lactogen;
(b) providing a cDNA bovine placental lactogen genetic sequence; and
(c) providing vectors and hosts containing these sequences which permit the efficient commercial production of bovine placental lactogen.
These and still other objects and advantages of the present invention will be apparent from the description which follows. These embodiments do not represent the full scope of the invention. Rather, the invention may be employed in other embodiments. Reference is therefore made to the claims herein for interpreting the scope of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
I. General Overview
(a) We first screened a library of bovine genomic DNA prepared from fetal cotyledon using prolactin cDNA gene as a probe, and isolated small fragments of the lactogen DNA gene.
(b) We then inserted one such fragment of the bovine placental lactogen gene is a plasmid and grew-up large quantities of the DNA in an appropriate host.
(c) Separately, we converted a "soup" of bovine fetal cotyledon to a cDNA "soup".
(d) We then used the genomic fragment as a probe to find a cDNA fragment.
(e) We then used the cDNA fragment to find the longer cDNA.
II. Selection Of Prolactin Related Gene
To obtain genomic sequences similar to prolactin or growth hormone, a bovine genomic library from bovine fetal cotyledons was prepared. Construction and amplification of a bovine genomic library has been previously described (R. Woychik et al., Nucl. Acids Res. 10: 7197-7210 (1982)). Briefly, bovine DNA fragments generated by partial Mbo I digestion are ligated into the Bam HI arms of the lambda phage Charon 28. The average genomic insert is about 14.5 kb.
When screened with a bovine prolactin cDNA (see N. L. Sasavage et al., J. Biol. Chem. 257: 678-681 (1982)(prolactin cDNA) and a bovine growth hormone cDNA (see R. Woychik et al., Nucl. Acid Res. 10: 7197-7210 (1982)(growth hormone cDNA) at 32° C. and at 42° C. (50% formamide) appropriate lactogen gene segments can be isolated. (Bovine growth hormone won't work under these conditions, but prolactin does.) The idea is that at low temperatures and high salt concentration sequences of even lesser homology (similarity) will stick together, whereas at higher temperatures and low salt concentrations sequences only stick to their own kind.
If a known sequence (e.g. the prolactin cDNA) is radio-labelled by nick translation, and hybridized to the bovine placental lactogen gene, using Southern hybridization techniques (E. M. Southern, J. Mol. Biol. 48: 503-517 (1975)), parts of the bovine placental lactogen gene will stick to the labelled prolactin at one condition, yet separate at slightly higher temperature.
A gene fragment identified by this scheme (named bP04) hybridized to prolactin cDNA at 32° C., but not at 42° C. This indicated that bP04 contained some sequence homology to prolactin, but was not part of the prolactin gene. It should be noted that the bP04 did not significantly hybridize to bovine growth hormone cDNA at either 32° C. or 42° C.
A Pstl restriction fragment of bP04 containing a part of the region with prolactin homology was cloned into the Pstl site of pBR322. The resulting plasmid was named pb PLgn04-3. As a confirmation that the fragment was not prolactin, the genomic insert from pbLgn04-3 was found to hybridize specifically to bovine placental poly(A)-containing RNA by RNA blotting, but not to bovine pituitary or liver RNA (prolactin hybridizes primarily to pituitary RNA).
The genomic insert of pbPLgn04-3 was used to rescreen the genomic library under high stringency hybridization conditions (42° C., 50% formamide). Two further genomic clones were identified., bP12 and bP13. Both hybridized specifically to pbPLgn04-3, and both hybridized to prolactin cDNA at 32° C., but not at 42° C. Genomic clones bP04 and bP12 have similar yet distinct restriction maps, while bP13 is very different from the others.
III. Formation Of Bovine Placental cDNA "Soup"
Additional bovine fetal cotyledons were collected at time of slaughter, immediately frozen in liquid nitrogen, and then stored at -70° C. Frozen tissue was homogenized in a Tris/NaCl buffer containing 40 mM vanadyl-ribonucleoside complex (VRC, synthesized as described by S. L. Berger et al., Meth. Enzymology 79: 59-68 (1981), and 1 mg/ml heparin as ribonuclease inhibitor). The homogenate is deproteinated by repeated extraction with buffer saturated phenol and chloroform until the VRC color is gone. This is followed by an extraction with ether.
Crude bovine RNA is then separated by cesium chloride density gradient centrifugation (V. Glisin et al., Biochemistry 13: 2633-2637 (1974)). Poly(A)-containing RNA is enriched from the RNA pellet by two passes on an oligo dT-cellulose affinity column. J. Sala-Trepet et al., Biochem. Biophys. Act 519: 173-183 (1978).
To produce the cDNA from the RNA, one has two alternatives. One can use an S 1 nuclease digestion step to cleave the hair-pin loop between first and second cDNA strands, and make both ends of the cDNA blunt-ended. However, this procedure often does not yield full-length sequences due to the S 1 nuclease digestion. Another alternative for the second strand is similar to that described by H. Land et al., Nucl. Acid Res, 9: 2251-2266 (1981). In this strategy, the first-strand synthesis reaction is analogous to the procedure of T. Maniatis et al., "Molecular Cloning, A Laboratory Manual". Pp 229-242 Cold Spring Harbor (1982). First-strand synthesis (changing the RNA to cDNA by reverse transcriptase) is primed with oligo dT. The reaction contains a human placental protein inhibitor of ribonuclease activity.
After first-strand synthesis, the reaction mixture is deproteinated with phenol:chloroform, the RNA base hydrolyzed, and the single-stranded cDNA purified by column chromatography. Single-stranded cDNA is tailed at the 3'-ends with dCTP using terminal deoxynucleotidyl transferase (TdT, H. Land et al., Nucl. Acids Res. 9: 2251-2266 (1981). Oligo dG will be hybridized to the dC-tailed cDNA, providing a primer for second-strand synthesis.
Second-strand synthesis is an E. coli polymerase I reaction, followed by a reverse transcriptase reaction similar to that used in the first-strand reaction. Using these enzymes sequentially gives maximal second-strand synthesis due to the presence of different stopping sequences in the template for the two enzymes (See T. Maniatis et al., supra).
The first-strand tailing step obviates need for a S 1 nuclease reaction, and the proportion of full-length sequences is maximized. Double-stranded cDNA is tailed with dCTP using TdT enzyme. Tailed, double-stranded cDNA is then sized by agarose gel electrophoresis, and DNA of lengths between given ranges, e.g. 1000 and 1200 bp, is extracted. (The mature lactogen message is believed to be between these ranges based on the protein size.) This sizing step greatly increases the proportion of lactogen-containing clones and increases the efficiency of cDNA library screening. Sized, double-stranded cDNA are then annealed with Pst I cut, dG-tailed pBR322, and used to transform E. coli strain HB101. Transformation is by a CaCl 2 method on tetracycline plates.
IV. Selection Of The cDNA Of Interest
Thus far, we have prepared a cDNA "soup" in part III, and a probe to help find the cDNA of interest in part II. The pbPLgn04-3 insert (the probe) is then used to screen a cDNA library.
To screen the cDNA colonies as described above, the colonies are transferred to 96-well microtiter plates containing L-broth plus tetracycline. Library screening uses a 96-well filter block where aliquots of each well are filtered onto nitrocellulose or GeneScreen (New England Nuclear) filters. The cells are lysed and the DNA fixed to the filter. Filters are washed extensively with a 2xSSC, 0.1% SDS solution to minimize hybridization background.
From 237 colonies screened, one specifically hybridized to the pbPLgn04-3 genomic insert. As test, the cDNA (360 bp) specifically hybridized to bovine placental RNA (RNA blotting), but not to bovine pituitary or liver RNA. Thus, it was not a prolactin gene fragment.
To obtain a longer cDNA, a second library was constructed using only insert lengths of 600 to 1300 bp. This library was then screened with that cDNA fragment of 360 bp, specifically identifying 20 clones from 1650 recombinants screened. The longest of these was pbPL10 with an insert length of about 875 bp, believed to represent 93% of the coding length. As a test, the pbPL10 insert was hybridized to RNA blots containing bovine placental, pituitary and liver RNA. As with the genomic fragment pbPLgn04-3 and the 360 bp cDNA, pbPL10 hybridized specifically to placental RNA.
Sequence analysis of the cDNA pBPL10, containing 777 bp of coding sequence and 162 bp of the 3' region, reveals strong homology to the sequence for bovine prolactin reported in N. L. Sasavage et al., J. Biol. Chem. 257: 678-681 (1982); W. Miller et al., DNA 1: 37-50 (1981). These 939 bp are 74% homologous to prolactin cDNA at the level of nucleotide sequence. Translation of the sequence indicates 39% homology in the amino acid sequence of the two proteins.
Using pbPL10, a full lactogen cDNA can then be identified by similar techniques. While it is unclear at present whether other lactogen genes exist (or whether the researchers have identified the only lactogen gene), this "brick by brick" technique should be appropriate for use to identify them as well.
Although the especially preferred embodiments of the invention have been described above, it should be noted that the invention is not so limited. In this regard, there may be various other modifications and changes to these embodiments that are within the scope of the invention.
For example, while one bovine placental lactogen cDNA has been isolated, there may be other bovine placental lactogen genes, and the claims are meant to cover them as well. Further, it is expected that through use of conventional recombinant techniques various small modifications and changes in the genetic sequence (such as controllers, triggers, etc.) might also be possible.
Also, E. coli derivatives are obviously not the only possible hosts. Numerous other hosts suitable for storage and/or protein production are possible. It might also be noted that plasmids are not the only possible vectors. Other vectors (e.g. phages) might also be suitable.
All such structures are to be deemed to be within the scope of the invention. | Portions of the genetic sequence coding for bovine placental lactogen are isolated and a cDNA variant of the bovine placental lactogen gene is then formed and isolated. Upon cloning of the cDNA gene sequence and culturing of a resulting hose, large quantities of bovine placental lactogen can be produced. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a vehicular display control device that controls display contents to be provided to a driver of a vehicle, and more particularly, to a vehicular display control device that informs the driver of an appropriate warning according to a risk level of a problematic situation of the vehicle.
[0003] 2. Description of the Related Art
[0004] Conventionally, vehicles are equipped with a plurality of indicators that keep the passengers riding in a vehicle updated about various situations such as the remaining amount of vehicle fuel or status of turn indicator lamps.
[0005] With the advent of car navigation systems with inbuilt display, a technology to display information and warnings on the inbuilt display is becoming prevalent.
[0006] A car navigation system can be used to display more detailed information about various situations as compared to conventional indicators. Moreover, the displayed information can be varies according depending on the transition in the situations. For example, Japanese Patent Application Laid-Open No. 2006-17652, Japanese Patent Application Laid-Open No. 2002-46505, Japanese Patent Application Laid-Open No. 2002-236955, and Japanese Patent Application Laid-Open No. H10-236243 disclose techniques for repetitively displaying a warning about a problematic situation until the problem is resolved.
[0007] By using the abovementioned technology, passengers riding in a vehicle can be updated about various problematic situations such as low fuel or continuous flashing of a turn indicator lamp. Although the passengers need to be warned about each problematic situation, the risk level of each problem is different if a vehicle is driven with the problem unresolved. For example, while riding in a vehicle, the risk level for low fuel is different than the risk level for a half-shut door.
[0008] Thus, it is necessary not only to inform the passengers about a problematic situation but also to warn how risky it is to ride in a vehicle without resolving the problem.
[0009] However, in a conventional technology, a warning issued to the passengers does not vary according to the risk level of each problematic situation. As a result, in the case of a high risk situation, there is a possibility that a passenger ignores the warning by cancelling the warning display and continues to ride in the vehicle without resolving the problem. On the other hand, in the case of a low risk situation, there is a possibility that a passenger cannot purposely cancel the warning display after reading the warning or the warning is repetitively displayed after being canceled.
SUMMARY OF THE INVENTION
[0010] It is an object of the present invention to at least partially solve the problems in the conventional technology.
[0011] According to an aspect of the present invention, there is provided a vehicular display control device including a first determining unit that determines contents of a warning, when an event arises in which at least one of a driver and a passenger of a vehicle needs to be warned of a situation of the vehicle; a second determining unit that determines a risk level of the problematic situation based on the contents of the warning determined by the first determining unit; and a display control unit that displays information on the situation of the vehicle on display in an interrupting manner in a display mode that is set according to the risk level.
[0012] The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic diagram of a vehicular display control device according to a first embodiment of the present invention;
[0014] FIG. 2 is an exemplary diagram for explaining a plurality of problematic situations that may arise in a vehicle, risk levels for those situations, and display modes for the risk levels;
[0015] FIG. 3 is an exemplary diagram for explaining a warning that pops up over other information being displayed on a display screen;
[0016] FIG. 4 is a flowchart for explaining the overall operations performed by the vehicular display device control unit;
[0017] FIG. 5 is a flowchart for explaining the operations performed by the vehicular display device control unit when the risk level of a problematic situation is determined to be high;
[0018] FIG. 6 is a flowchart for explaining the operations performed by the vehicular display device control unit when the risk level of a problematic situation is determined to be moderate; and
[0019] FIG. 7 is a flowchart for explaining the operations performed by the vehicular display device control unit when the risk level of a problematic situation is determined to be low.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Exemplary embodiments of the present invention are described in detail below with reference to the accompanying drawings. The present invention is not limited to these exemplary embodiments.
[0021] FIG. 1 is a schematic diagram of a vehicular display control device 1 according to a first embodiment of the present invention. The vehicular display control device 1 is connected to a vehicle-body electronic control unit (ECU) 30 , an engine control ECU 60 , and a power management ECU 70 via a bus network.
[0022] The power management ECU 70 manages a vehicle battery and transmits the battery power over the bus network.
[0023] The engine control ECU 60 controls the engine operations depending on the use of an accelerator pedal in the vehicle. The engine control ECU 60 includes a coolant temperature sensor 61 and an exhaust temperature sensor 62 , and transmits information regarding the coolant temperature and the exhaust temperature of the vehicle over the bus network.
[0024] The vehicle-body ECU 30 controls the operations of various equipments and functions provided on the vehicle body. The vehicle-body ECU 30 is connected with a lamp control mechanism 40 , a door switch 51 , a hood switch 52 , a seat belt sensor 53 , a hand break sensor 54 , a washer fluid indicator 55 , a fuel indicator 56 , an oil indicator 57 , and an indicator operating unit 33 .
[0025] The lamp control mechanism 40 controls operations of a plurality of lamps provided on the vehicle. The lamps include turn indicator lamps 41 (i.e., winker lamps), brake lamps (not shown), and head lamps (not shown). Moreover, the lamp control mechanism 40 includes a lamp burnout sensor 42 for detecting burned-out lamps.
[0026] The door switch 51 switches between an OFF state when a vehicle door is open and an OFF state when a vehicle door is closed. Similarly, the hood switch 52 switches between an ON state when the vehicle hood is open and an OFF state when the vehicle hood is closed.
[0027] The seat belt sensor 53 informs the vehicle-body ECU 30 whether seat belts are fastened. Similarly, the hand break sensor 54 informs the vehicle-body ECU whether the hand break is applied.
[0028] The washer fluid indicator 55 informs the vehicle-body ECU 30 when the amount of washer fluid falls below a specific amount. Similarly, the fuel indicator 56 informs the vehicle-body ECU 30 when the amount of vehicle fuel (e.g., gasoline) falls below a specific amount. The oil indicator 57 informs the vehicle-body ECU 30 when the amount of vehicle oil falls below a specific amount.
[0029] The vehicle-body ECU 30 includes a situation determining unit 31 and an indicator control unit 32 . The situation determining unit 31 obtains various information from the power management ECU 70 , the engine control ECU 60 , the lamp control mechanism 40 , the door switch 51 , the hood switch 52 , the seat belt sensor 53 , the hand break sensor 54 , the washer fluid indicator 55 , the fuel indicator 56 , and the oil indicator 57 , and determines whether a problematic situation has arisen in the vehicle for which passengers riding in the vehicle need to be warned.
[0030] When the situation determining unit 31 determines it necessary to issue a warning to the passengers, the indicator control unit 32 controls the indicator operating unit 33 to switch ON an indicator corresponding to the problematic situation. The indicator control unit 32 also transmits details of the warning over the bus network.
[0031] The vehicular display control device 1 includes a control unit 10 and an input-output (I/O) unit 20 . The I/O unit 20 further includes a display screen 21 for displaying various information to the passengers, a speaker 22 for outputting voice information to the passengers, a touch panel 23 from which the passengers can input instructions, and a switch 24 .
[0032] The control unit 10 controls the operations of the I/O unit 20 . More particularly, depending on instructions from the passengers or operating conditions of other equipments in the vehicle, the control unit 10 controls the I/O unit 20 to output information by using the display screen 21 and the speaker 22 . The control unit 10 can control, e.g., car navigation and inform the passengers about routes to a destination or facilities in the vicinity of current location of the vehicle.
[0033] Moreover, the control unit 10 monitors the information transmitted over the bus network. After the vehicle-body ECU 30 transmits details of a warning over the bus network, the control unit 10 obtains the details and pops up the warning over other information being displayed on the display screen 21 .
[0034] The control unit 10 includes a warning determining unit 11 , a risk determining unit 12 , a display control unit 13 , and a monitoring control unit 14 . The warning determining unit 11 monitors the bus network and determines a warning from the information being transmitted over the bus network.
[0035] The risk determining unit 12 determines a risk level for a problematic situation described in the details of a warning. The display control unit 13 controls displaying the warning on the display screen 21 based on a display mode set corresponding to the risk level.
[0036] When a warning is to be issued about a problematic situation, the monitoring control unit 14 starts monitoring that particular situation and varies the risk level depending on the transition in the situation.
[0037] Given below is the description about a plurality of problematic situations that may arise in a vehicle, risk levels for those situations, and display modes for the risk levels with reference to FIG. 2 . As shown in FIG. 2 , situations such as riding in a vehicle without fastening a seatbelt, riding in a vehicle while keeping the hand brake in an applied state, riding in a vehicle while keeping flashers ON, and riding in a vehicle while keeping a turn indicator lamp ON are determined to be low-risk situations.
[0038] On the other hand, a situation such as increase in the coolant temperature or the exhaust temperature is determined to be a moderate-risk situation, while a situation such as riding in a vehicle while keeping a door or the vehicle hood half-shut is determined to be a high-risk situation.
[0039] Meanwhile, a situation such as low fuel, low oil, oil deterioration, low washer fluid, or low battery charge is initially determined to be a low-risk situation. Even if such a situation arises, the control unit 10 has some leeway in switching the corresponding indicator ON such that the passengers are warned about the situation. However, the risk level of such a situation changes to moderate or high if the situation gets worse in the course of time.
[0040] For example, in the case of low fuel, the monitoring control unit 14 first determines the situation to be a low-risk situation, starts monitoring the travel distance or the engine status, and varies the risk level to moderate or high depending on the monitoring result.
[0041] Similarly, in the case of low oil or oil deterioration, the monitoring control unit 14 first determines the situation to be a low-risk situation, starts monitoring the travel distance or the engine status, and varies the risk level to moderate or high depending on the monitoring result. In the case of low washer fluid, the monitoring control unit 14 first determines the situation to be a low-risk situation, monitors the number of times for which the washer fluid is consumed thereafter, and varies the risk level to moderate or high as the amount of washer fluid further decreases. Similarly, in the case of low battery charge, the monitoring control unit 14 first determines the situation to be a low-risk situation, monitors the amount of battery charge consumed thereafter, and varies the risk level to moderate or high as the battery charge further decreases.
[0042] In the case of a display mode for a low-risk situation, a warning pops up over other information being displayed on the display screen 21 . However, it is possible for a passenger to cancel the warning display from the display screen 21 . The warning is not redisplayed thereafter.
[0043] In the case of a display mode for a moderate-risk situation, after a warning pops up over other information being displayed on the display screen 21 , it is possible for a passenger to temporarily cancel the warning display. However, the warning is repetitively displayed on the display screen 21 after, e.g., a specific time interval or a specific travel distance until the problem is resolved.
[0044] In the case of a display mode for a high-risk situation, a warning pops up over other information being displayed on the display screen 21 . Moreover, a passenger is not able to cancel the warning display. That is, the warning is continuously displayed until the problem is resolved.
[0045] FIG. 3 is an exemplary diagram for explaining a warning that pops up over other information being displayed on a display screen. The display screen in FIG. 3 is originally shown to be displaying a music playback screen as selected by the passengers. However, when, e.g., the vehicle fuel falls below a specific amount (a low fuel situation), a warning pops up over the music playback screen. That is, the display of the music playback screen is interrupted by the warning display.
[0046] The warning informs the passengers that the vehicle is on low fuel as well as projects a possible travel distance in the current low fuel situation. Moreover, if the situation is determined to be a low-risk situation or a moderate-risk situation, an OK button is provided on the warning such that the passengers can touch the OK button to at least temporarily cancel the display after reading the warning.
[0047] FIG. 4 is a flowchart for explaining the overall operations performed by the control unit 10 .
[0048] First, the control unit 10 monitors the information transmitted over the bus network (Step S 101 ). When a warning is transmitted by the vehicle-body ECU 30 over the bus network (Yes at Step S 102 ), the warning determining unit 11 determines the details of that warning (Step S 103 ). The risk determining unit 12 then determines a risk level for a problematic situation described in the details of the warning (Step S 104 ). The display control unit 13 controls displaying the warning on the display screen 21 based on a display mode set corresponding to the risk level (Step S 105 ). The system control then returns to Step S 101 .
[0049] The process of displaying a warning on the display screen 21 differs for each risk level, viz., low, moderate, and high. When the risk level is determined to be high as shown in FIG. 5 , the display control unit 13 first pops up a warning over other information being displayed on the display screen 21 (Step S 201 ) and keeps displaying the warning. When the problem corresponding to the warning is resolved (Yes at Step S 202 ), the display control unit 13 cancels the warning display (Step S 203 ).
[0050] When the risk level is determined to be moderate as shown in FIG. 6 , the display control unit 13 first pops up a warning over other information being displayed on the display screen 21 (Step S 301 ) and provides an OK button on the warning display such that the passengers can temporarily cancel the warning display after reading the warning (Step S 302 ).
[0051] When the problem corresponding to the warning is resolved (Yes at Step S 303 ), the display control unit 13 cancels the warning display (Step S 307 ).
[0052] However, when the problem corresponding to the warning is not resolved (No at Step S 303 ), the display control unit 13 determines whether the OX button is touched (Step S 304 ). If the OK button is not touched (No at Step S 304 ), the system control returns to Step S 301 and the warning is kept displayed on the display screen 21 .
[0053] If the OK button is touched (Yes at Step S 304 ), the warning display is temporarily cancelled (Step S 305 ). After a certain condition such as a specific time interval or a specific travel distance is satisfied (Yes at Step S 306 ), the system control returns to Step S 301 and the warning is redisplayed on the display screen 21 .
[0054] When the risk level is determined to be low as shown in FIG. 7 , the display control unit 13 first determines whether a warning has been previously displayed and cancelled (Step S 401 ). Only when the warning is not previously displayed (No at Step S 401 ), the display control unit 13 pops up the warning over other information being displayed on the display screen 21 (Step S 402 ) and provides an OX button on the warning display such that the passengers can permanently cancel the warning display after reading the warning (Step S 403 ).
[0055] When the problem corresponding to the warning is resolved (Yes at Step S 404 ), the display control unit 13 cancels the warning display (Step S 408 ).
[0056] When the problem corresponding to the warning is not resolved (No at Step S 404 ), the display control unit 13 first determines whether the OK button is touched (Step S 405 ). If the OK button is not touched (No at Step S 405 ), the system control returns to Step S 402 and the warning is kept displayed on the display screen 21 .
[0057] If the OK button is touched (Yes at Step S 405 ), the display control unit 13 cancels the warning display (Step S 406 ) and stores the history of displaying the warning and then cancelling the warning display (Step S 407 ). Such history is stored for each displayed warning and deleted after a predetermined amount of time. The vehicular display control device 1 can be configured to delete such history at the time of, e.g., switching OFF the engine or turning the power of the vehicle ON for first time in a day.
[0058] To sum up, the vehicular display control device 1 according to the first embodiment detects a problematic situation in a vehicle, determines the risk level corresponding to the situation, and issues a warning to the passengers by using a display mode appropriate for the determined risk level.
[0059] Thus, when a high-risk situation such as riding in a vehicle while keeping a door or the vehicle hood half-shut arises, the warning is continuously displayed without allowing the passengers to cancel the warning display. On the other hand, when a low-risk situation such as riding in a vehicle without fastening a seatbelt arises, the passengers are allowed to cancel the warning display.
[0060] As a result, it is possible to correctly warn the passengers about the risk level of a problematic situation thereby improving the reliability of the vehicular display control device 1 and contributing to driving safety.
[0061] Moreover, e.g., in the case of low oil or oil deterioration, the risk level keeps changing depending on the remaining amount of the oil or the degree of oil deterioration, respectively. Thus, as soon as such situations arise, the travel distance or the engine status is continuously monitored such that the risk level can be varied according to the changing monitoring results. Such a configuration facilitates in simplifying the monitoring mechanism as well as achieving efficient monitoring.
[0062] In addition to detecting a burned-out lamp by using the lamp control mechanism 40 , a warning can be displayed to inform the passengers about the burned-out lamp. Moreover, if the burned-out lamp happens to be a head lamp, it is possible to vary the risk level depending on the time of day.
[0063] Furthermore, the risk levels are not limited to low, moderate, and high, and can be appropriately set along with the corresponding display modes.
[0064] Moreover, instead of controlling the display screen 21 , the vehicular display control device 1 can be configured to control an external display device.
[0065] As described above, according to an aspect of the present invention, it is possible to control the display of a warning according to the risk level of a problematic situation and hence contribute to driving safety.
[0066] Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth. | When an event arises in which at least one of a driver and a passenger of a vehicle needs to be warned of a situation of the vehicle, a first determining unit determines contents of a warning, and a second determining unit determines a risk level of the problematic situation based on the contents of the warning determined by the first determining unit. A display control unit displays information on the situation of the vehicle on display in an interrupting manner in a display mode that is set according to the risk level. | 1 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to the application of chemical treatments to cotton and cotton-containing fabrics to impart smolder resistance to the products made therefrom. The method of this invention is of particular significance to the users of upholsterytype, heavy weight fabrics, and is considered a substantial improvement over the known smolder-retardant finishes.
(2) Description of the Prior Art
It is known that cellulosic fabrics are highly susceptible to cigarette ignition, a smoldering-type reaction. It is also known that the mechanism of flame retardance and smolder resistance are decidedly different, so much so that flame retardant fabrics generally contribute to smoldering hazard associated with textiles.
The smoldering characteristics and imparting smolder-resistance to cotton-containing fabrics have been studied very little. Backcoating with a latex or treatment with sulfur, or with boric acid, have been mentioned in the literature as methods for imparting smolder resistance to cotton-containing fabrics.
Nestor Knoepfler et al disclose in U.S. Pat. No. 4,012,507 a vapor-phase boric acid treatment for application to cotton batting. Special equipment and techniques must be employed in that process, thus making it unattractive for its use with heavyweight upholstery textiles.
Chemcial Abstracts (C.A. 89, 76594e), indicates that McCarter in patent application Ser. No. 870,385 now abandoned discloses the use of sulfur as a smolder inhibiting agent for cellulosic insulations. The method of application indicated by that disclosure indicates that it is not practical for fabrics. Sulfur requires relatively large amounts of deposition on the substrate to be capable of imparting smolder resistance. Results obtained in the deposition on heavyweight fabrics have been erratic. The resulting fabrics are quickly associated with the obnoxious odor of sulfur.
Backcoating as a method of imparting smolder resistance is objectionable because the coatings impair the aesthetic properties of certain fabrics, essentially heavyweight fabrics, and therefore backcoatings do not lend themselves to applications to all types of cotton-containing fabrics.
Dusting and hot aqueous treatments have been mentioned as smolder-resistant process for cellulosic materials. The dusting of boric acid as applied to batting is not feasible for textiles. The hot aqueous treatment requires energy to be supplied to the solution at all times, thus making the system unattractive. Also, such a system is not ameanable for use on low wet pickup finishing equipment. Also, the availability of boric acid is limited thereby making the treatment economically impractical.
SUMMARY OF THE INVENTION
A process for imparting smolder resistance to cotton and cotton-containing fabrics is disclosed. Tests indicate that there is a synergistic effect in the combination of boron, phosphorus, and nitrogen, and in imparting resistance to cigarette ignition to these textiles when applied under the proper conditions. An aqueous solution containing a boron compound is mixed with a phosphorus-containing compound, then an N-methylol compound is added. This solution is then applied to a cotton or cotton-containing textile, dried, then cured.
The main object of this invention is to provide a means of rendering these textiles smolder resistant. This has been accomplished by the process of the present invention, which was designed to be employed particularly in the treatment of upholstery-type fabric, employing conventional textile equipment, especially those suitable to the use of low energy.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the process of the present invention, generally, the preferred embodiment consists of (a) formulating the chemical mixture which contains the right porportions of a boron compound preferably borax--a phosphorus compound and an N-methylol compound, (b) impregnating the organic fibrous material (the fabric) with the aqueous solution, (c) drying the impregnated fabric, and (d) curing the fabric, thus producing in the fibrous structure insoluble polymeric materials which contain synergistic proportions of boron, phosphorus, and nitrogen.
Specifically, the present invention provides smolder resistant organic fibrous material and a process for producing said material by any convenient technique, such as by padding or loop-transfer onto the fabric, to a wet pickup of about from 15% to 100% with a solution containing borax, for example, in a percentage of about 5% to 35% in combination with a phosphorus compound such as, for example, phosphoric acid in a percentage of about from 1% to 7%, and an N-methylol compound in a percentage of about from 2.5% to 15%. The preferred drying conditions are temperatures of about 120° to about 185° F. for about from 2 to 12 minutes, using the longer times with the lower temperatures. This is follwed by a preferred curing of about from 1 to 7 minutes at about from 125° to 300° F.
The preferred solution for impregnating the organic fibrous material of this invention are prepared thusly; Borax is suspended in water, and the preferred phosphorus agent is added, until the borax is completely dissolved, to give a solution containing about from 5% to 40% borax, the preferred range being 9% to 29%. To this solution the nitrogenous agent is added with stirring, to give a concentration of 1% to 15%, the preferred range being 2.5% to 12%.
Suitable N-methylol compounds are amides prepared by reacting formaldehyde with amides of the group glycoluril, urea, dihydroxyethylene urea, melamines, triazones, triazines, and carbamates. Although these would be preferred because of the availability of experimental data on these one should not expect this fact to limit the scope of the N-methylol compounds of this invention.
Phosphorus compound suitable for the process of the present invention are phosphoric acid, monosodium phosphate, disodium phosphate, trisodium phosphate, monoammonium phosphate, diammonium phosphate, and triammonium phosphate, in the range of 1.0% to 10%, the preferred concentration being about from 2.5% to 6%.
We have found that by reacting a boron compound, for example borax, with a phosphorus compound, such as phosphoric acid, and an N-methylol nitrogen compound, such as methylated trimethylolmelamine (MTMM) a product is obtained that imparts a high degree of smolder retardance to cotton-containing textiles. The need for all three agents together with their synergistic activity can be clearly seen in the results of a number of experiments, as shown in Table I. These applications were made on 100% cotton fabric.
In these evaluations B 2 O 3 concentration was determined by an alkali titration of aliquots obtained by aqueous extracts of the cotton samples. Smolder resistance was measured by the proposed cigarette ignition test of the National Bureau of Standards. In Table I the lowest class is D, and the highest class, using fiberglass panel substrate is class B. The applications were made onto 16 oz/yd 2 cotton fabric.
TABLE I______________________________________ Add-on B.sub.2 O.sub.3Treatment % % Class______________________________________Borax (alone) 10.6 5.75 DMTMM (alone) 15.0 none CBorax-H.sub.3 PO.sub.4 7.8 4.07 CBorax-H.sub.3 PO.sub.4 --MTMM 8.0 2.73 B Note: When the applications were made onto 9.8 oz/yd.sup.2 the following observations were made.
Borax-TMM 5.6 1.89 DBorax H.sub.3 PO.sub.4 --MTMM 4.7 1.86 B______________________________________
The importance of the inclusion of the phosphorus compound in the process of the present invention is demonstrated in the following table (Table II). Applications are to 16 oz/yd 2 100% cotton fabric.
TABLE II______________________________________ Concentration Add-on B.sub.2 O.sub.3Compound % % % Class______________________________________H.sub.3 PO.sub.4 2.5 9.2 2.78 B(NH.sub.4)H.sub.2 PO.sub.4 3.3 13.0 2.97 B(NH.sub.4).sub.2 HPO.sub.4 4.1 9.9 2.89 BNaH.sub.2 PO.sub.4 4.1 11.1 3.43 BOxalic Acid 3.0 10.3 2.86 DGlycolic Acid 3.0 9.1 2.89 DCitric Acid 2.5 11.6 3.54 D______________________________________
The acids such as oxalic, and the like, dissolved the borax but did not impart any smolder resistance to cotton textiles. Therefore, one must conclude that the phosphorus compound does not just function as a dissolving agent for borax or for the possible formation of boric acid but is an integral and necessary part of the system for imparting smolder resistance. This invention for imparting smolder resistance shows the synergistic effect of three types of compounds, namely boron-, phosphorus-, and nitrogen-containing compounds.
Impregnated organic fibrous materials are dried and heated to an elevated temperature by any conventional manner, such as, for example, an oven, to produce the insoluble material in and on the fibers. It is of advantage to dry the organic fibrous material at a temperature of about from 120° to 185° F. before it is cured at a temperature of about from 225° to 275° F. However, it can also be dried and cured in a single step at the temperature range of about from 225° to 300° F.
Application of the treatment can be done with any textile equipment, such as, for example, with a padder, spray, vacuum impregnator, or foam and transfer technique equipment.
The transfer technique being perferred because less wet pickup is attained and therefore affords a considerable saving of costly energy. This system is particularly suitable to such application. The attractiveness of such a system is enhanced because of surface (pile fabrics) of the organic fibrous materials. Low wet pickup systems are also equally suitable for heavy weight materials where large amounts of energy are necessary for drying these materials.
Surface active agents, water repellants, soil-release agents and other conventional textile modifiers can be added to the treating emulsion.
In the process of the invention the terms "organic fibrous material" or "textile material" include cellulosic fibers, such as cotton, ramie, rayon, paper, cardboard, and their physical and chemical modifications, and thermoplastic fibers, such as polyester, polypropylene, polyamide, acrylics, and acetate.
The following examples are provided to illustrate the invention and should not be construed as limiting the invention in any manner whatever.
EXAMPLE 1
A 16 oz/yd 2 100% cotton fabric was padded to give a 73% wet pickup with a solution containing 10% borax, 2.5% H 3 PO 4 , and 5% trimethylolmelamine. The fabric was dried at 185° F. for 10 minutes and cured at 250° F. for 4 minutes. The fabric after equilibration had 9.2% add-on containing 2.78% B 2 O. The fabric was determined to be Class B. [for the classifying of these refer to Proposed Standard for the Flammability (Gigarette Ignition Resistance) of Upholstered Furniture (PFF 6-78)].
EXAMPLE 2
A 9.8 oz/yd 2 100% cotton fabric was padded to give a 54% wet pickup with a solution containing 10% borax, 2.5% H 3 PO 4 , and 5.2% dimethyloldihydroxyethylene urea. The sample was dried at 185° F. for 12 minutes, and cured at 275° F. for 7 minutes. The fabric had a 6.2% add-on containing 2.28% B 2 O 3 . The fabric was determined to be in Class B.
EXAMPLE 3
A 20 oz/yd 2 41% rayon--59% cotton fabric was padded with a solution containing 7% borax, 2% H 3 PO 4 , and 3.5% methylated trimethylolmelamine (MTMM) to give a 100% wet pickup. The fabric was dried at 185° F. for 12 minutes, and cured at 275° F. for 7 minutes. The fabric had 7.0% add-on containing 2.53% B 2 O 3 , and was determined to be in Class B.
EXAMPLE 4
The procedure of Example 1 was followed except that 3.3% monoamonium phosphate was substituted for H 3 PO 4 . The fabric had a 13% add-on containing 5.65% B 2 O 3 , and was determined to be in Class B.
EXAMPLE 5
The procedure of Example 1 was followed except that 4.1% diammonium phosphate was substituted for H 3 PO 4 . The fabric had a 9.9% add-on containing 2.89% B 2 O 3 , and was determined to be Class B.
EXAMPLE 6
The procedure of Example 1 was followed except that 4.1% disodium phosphate was submitted for H 3 PO 4 . The fabric had 11.1% add-on containing 3.43% B 2 O 3 , and was determined to be Class B.
EXAMPLE 7
A 9.8 oz/yd 2 cotton fabric was loop-transfered with a solution containing 29% borax, 6% H 3 PO 4 , 5% methylated trimethylolmelamine (MTMM), and 4% styrene-butadiene-vinylidene chloride (a latex additive) to give a wet pick up of 19%. The treatment was transferred to the back of the fabric. The fabric was dried 185° F. for 7 minutes, and dried 275° for 7 minutes. The fabric had a 5.9% add-on containing 2.19% B 2 O 3 , and was determined to be Class B.
EXAMPLE 8
An 11.3 oz/yd 2 100% cotton fabric and a 20.2% 49% rayon--23% cotton--25% acetate--3% polyester fabric were padded with a solution containing 5% borax, 1.3% H 3 PO 4 , and 5% MTMM. The cotton fabric and the blend fabric had 87% and 97% wet pickup, respectively. The samples were dried 12 minutes at 185° F., and cured at 275° F. for 7 minutes. The 100% cotton fabric had an add-on of 6.8% containing 1.84% B 2 O 3 , and the blend fabric had a 7.3% add-on containing 2.39%. Both samples were determined to be Class B.
EXAMPLE 9
A 16 oz/yd 100% cotton fabric was loop-transfered so that a solution containing 29% borax, 5.5% H 3 PO 4 , and 12% MTMM was applied to the face of the fabric to give a 37% wet pickup. The fabric, after drying for 7 minutes at 185° F., and curing for 7 minutes at 275° F. had an add-on of 13.4% containing 3.88% B 2 O 3 , and was determined to be Class B.
EXAMPLE 10
A 20.2 oz/yd 49% rayon--23% cotton--25% acetate--3% polyester fabric was treated with a soluition containing 22% borax, 5.5% H 3 PO 4 , and 10.5% MTMM to give an 18% wet pickup. The fabric was dried at 185° F. for 5 minutes and cured at 275° F. for 5 minutes. The fabric had a 4.3% add-on and was determined to be Class B. | Smolder resistance is imparted to cotton and cotton-containing fabrics by applying a certain boron-nitrogen-phosphorus system to the fabric, employing conventional equipment. An inorganic boron compound is placed in solution with a phosphorus-containing compound, then a nitrogen-containing compound is added. The aqueous mixture is applied using conventional textile equipment, dried, and cured by standard methods. | 3 |
[0001] This invention relates to a toilet cistern inlet valve.
[0002] Inlet valves for toilet cistern inlet valves are controlled by a water level sensing device usually a float, and it is well known that a float is provided at the end of an arm pivoted to the valve housing, the other end of the arm pressing on a small plunger having a sealing washer pad to press against the valve seat.
[0003] Also cistern inlet valves are known having a float slideable on the valve column connected to the inlet to the cistern, there being a small lever arm connecting the float to a valve member to close on a valve seat at the upper end of the column.
[0004] In all toilet cistern inlet valves it is desirable that the valve permit the reasonably rapid filling of the cistern, but at the same time be quiet in operation so that the noise produced by the rapid filling of the cistern is minimal. However to rapidly fill the cistern, the valve must be open to an extent to permit a large flow of water. In areas where the water supply is provided at high pressure, the valve must close off at a reasonably rapid rate, but should not be at a rate to produce a rebound shock wave to proceed back through the water supply line, in other words to produce water hammer. Thus it is desirable that there should be a reasonably soft closing of the valve without any likelihood of water hammer, irrespective of the water supply pressure.
[0005] It is an object of this invention to provide an improved toilet cistern inlet valve which is quiet in operation.
[0006] A further object of the invention is to provide a toilet cistern inlet valve in which the valve closes with little or no noise and in a manner which prevents or minimises shock waves in the inlet water supply line.
[0007] In order to describe the invention reference will now be made to the accompanying drawings in which
[0008] FIG. 1 is a general arrangement view of a valve embodying the invention,
[0009] FIG. 2 is a similar view of the upper portion of the valve,
[0010] FIG. 3 is an exploded view of the locking of the lower stem to the upper stem on the body,
[0011] FIG. 4 is a view of the upper valve body,
[0012] FIG. 5 is a view of the deflector skirt,
[0013] FIG. 6 is a view of the lower valve body,
[0014] FIG. 7 is an exploded view of the operative parts of the reed valve and diaphragm valve,
[0015] FIG. 8 is a further view of the controlling diaphragm valve and spacer,
[0016] FIG. 9 is an exploded view of a further form the cistern inlet valve,
[0017] FIG. 10 is a view of the float and adjustment, and
[0018] FIG. 11 is a view the operating button.
BRIEF DESCRIPTION OF THE INVENTION
[0019] There is provided according to the invention an inlet valve for a toilet cistern, said inlet valve including an inlet stem connected to a water supply, a canister surrounding said inlet stem, a float canister freely supported on said canister, an annular float adjustably positioned on said float canister, a pilot diaphragm valve, a diaphragm filling valve whereby the float canister opens the pilot diaphragm valve to open the diaphragm filling valve on the float canister lowering during the emptying of the cistern.
[0020] Preferably the pilot diaphragm valve is a star valve.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] The valve 1 comprises a mounting stem 2 and water supply inlet which supports the valve, the mounting lower stem being connected to an upper stem 3 , lower valve body 4 and upper valve body 5 housing the control valve assembly 6 . Surrounding the valve above the mounting stem 2 there is provided a freely supported float canister 7 carrying on its outside an annular float element 8 having friction pads 9 to engage the canister 7 whereby the float 8 may be adjustably positioned along the canister 7 . The canister 7 preferably has a canister extension 10 slideable on the canister 7 , the annular area between the canister extension and the stem providing the water outlet. The canister extension provides that the valve discharge may be carried to the base of the tank in which the valve is installed.
[0022] The lower stem has at its upper end 21 forming a housing for the adjustable stem locking device, the upper stem 3 being slideably received in the lower stem for adjustment purposes. The housing incorporates a shoulder 22 to locate a pressure sealing O-ring 23 , and internal ramped surface 24 to provide a wedging action and an external rebate to locate a retaining collar 25 .
[0023] The locking collet 26 has external profiles matched to the housing 21 such that vertical movement of the collet provides a wedging action resulting in a collapse of its internal diameter. The internal profile provides a lip, the shape of which is matched to profiles regularly spaced on the outside surface of the upper stem 3 , thus providing a mechanical restraint against movements between the parts when engaged. Clearance between the collet and the housing enables the internal lip to ride freely over the companion upper stem profiles when the collet is physically depressed into the housing. Thus the position of the upper stem relative to the lower stem is determined by the depth of the cistern, and the collet then being depressed to lock the two stems together. The retaining collar 25 is provided with an internal rebate the function of which is to secure its location when installed on the housing 21 . The retaining collar provides a limit to the expansion of the housing when subjected to the wedging action forces when the collet is pressed into its locking position.
[0024] The upper stem 3 is sized to telescope into the lower stem and has regular spaced external profiles to engage the locking collet. The lower end of the stem is fitted with a secondary O-ring to provide a pressure seal within the bore of the lower stem. The upper end of the upper stem is threaded 31 to accept the lower valve body 4 , the junction of which is profiled to accept an O-ring 32 to form a pressure seal. The internal profile of the upper end is sized to accept and locate a filter screen 33 which is a fine mesh element through which the water passes to retain particulate material and debris entrained in the water supply.
[0025] The lower valve body 4 incorporates the main flow path through the valve and supports the discharge deflector skirt 41 and upper valve body 5 and also houses the vortex diffuser 35 .
[0026] The flow path enters a choke restriction 44 a in the lower valve body 4 which controls the rate of flow and then passes upwards to the valve seat 42 on which the main diaphragm valve 43 closes. When the diaphragm valve 43 is open the flow crosses the valve seat and turns downward into the annulus surrounding the seat, passes through the vortex diffuser 35 and is discharged through a circular array of eight holes 36 connected to a radial discharge slot. The lower valve body has a threaded upper portion 44 to accept the upper valve body and a rebate 45 to locate and support the discharge deflector skirt 41 which is a ring shaped element with an internal rebate baffle companion to the lower valve body and a conical surface forming a downward deflecting annular slot when in companion with the lower valve body.
[0027] The upper valve body 5 is a cylindrical shaped element having an internal threaded base 51 companion with the lower valve body 4 and a tubular extension 52 which houses the actuator button plunger 53 . The body also incorporates a sealing surface profile 54 on the inside for the controlling diaphragm valve 55 . The tubular extension 52 is reinforced by eight stiffening webs 56 and is divided by eight vertical slots 57 forming four fingers which are free to articulate about their base. The inside surface of the fingers carry a profiled lip at the top to engage a groove 58 in the actuator button 53 such that the button, although free moving is retained in position. An aperture 59 , with stage-wise swaging and forming the valve seat 42 for the controlling diaphragm valve 43 connects the tubular extension with the internal cavity of the valve body.
[0028] The actuator button incorporates a metal pin 60 the function of which is to bear on the controlling diaphragm valve and trigger the opening cycle of the main diaphragm valve 43 . The limited movement of the plunger is controlled by the flange face of the mushroom head and the relative size of the retaining groove immediately below.
[0029] The function of the controlling diaphragm valve 55 is to depressurise the chamber above the main diaphragm valve 43 and to cause the diaphragm valve 43 to open. The controlling diaphragm 55 consists of a laminate of springy substrate and a resilient sealing pad 61 to seal on the sealing surface profile of valve seat 54 . The diaphragm is a six spoke star shape of thin material supported at the tips of each spoke. In a preferred embodiment the diaphragm material is a thin piece of stainless steel.
[0030] A circular shaped spacer 62 with a bridging core 63 locates and supports a clearance pin 64 . The bridging core has three regular spaced holes to allow fluid flow to pass through and provide material the centre to mount the pin 64 . The spacer 62 serves several functions. It supports and locates the controlling diaphragm valve 55 . It carries the clearance pin moulded integrally with the spacer and it clamps the diaphragm in position and preloads the diaphragm material to effect a pressure seal. It limits the stroke of the diaphragm insert movement. The ends of the spokes of the stainless steel diaphragm are located under the spacer and diaphragm insert 66 .
[0031] The diaphragm insert 66 is a circular shaped element with a profile that supports the resilient diaphragm valve 43 and incorporates a guide to centre the diaphragm on the valve seat. The insert has an aperture 67 in the centre through which the clearance pin passes, the aperture being modestly larger than the pin allowing a controlled flow from beneath the diaphragm valve 43 to above the diaphragm valve 43 to thus pressurise the chamber above the diaphragm valve 43 when the diaphragm valve 43 is closed.
[0032] The vortex diffuser 35 has a profile which divides the annulus chamber of the lower-valve body, the flow being through four slots 68 at the divergence of the inner diameter. In addition the diffuser supports the main diaphragm 43 from over travel during the valve closure operation.
[0033] As noted above surrounding the valve body is a float canister 7 which has a conical end cap 7 , two holes in the end cap permitting air displacement. The float canister in conjunction with the float element 8 and canister extension 10 is to apply sufficient force, under the influence of gravity to stroke the actuator button 53 against the resistance caused by the controlling diaphragm valve spring and hydraulic pressure within the valve body.
[0034] Thus in operation when the water is discharged from the cistern, the float, canister extension and canister move downwardly until the conical end cap depresses the actuator button. The actuator pin then depresses the controlling diaphragm valve 55 moving it from its seat to bleed the water from the chamber above the diaphragm 43 , water pressure beneath the diaphragm then lifts the diaphragm so that water passes over the seat, through the diffuser into the cistern.
[0035] When the water in the cistern reaches its fill level determined by the position of the float element on the canister the conical cap end moves away from the actuator button, and due to the spring pressure of the controlling diaphragm valve 55 , the controlling diaphragm valve 55 will close. Water will then pass in a controlled manner through the aperture and pressurise the chamber above diaphragm 43 to set diaphragm on its seat thus closing the valve.
[0036] Referring now to FIGS. 9 , 10 and 11 showing an alternate form of the invention where like parts retain the same numbering.
[0037] In the alternate form the float 8 is adjusted by screwing on the float canister to preselect the height of the water in the filled cistern. Also the actuator button has been modified to have the plunger fixed to the button.
[0038] Thus the cycle of operation of the cistern inlet valve is complete and the valve is now ready for the next operation.
[0039] Although one form of the invention has been described in some detail, the invention is not to be limited thereto but can include variations and modifications falling within the spirit and scope of the invention. | A toilet cistern inlet valve, said inlet valve including an inlet stem connected to a water supply, a canister surrounding said inlet stem, a float canister freely supported on said canister, an annular float adjustably positioned on said float canister, an upper valve body, a pilot diaphragm valve, and a diaphragm filling valve within the upper body whereby during the emptying of the cistern the float canister lowers and contacts an actuator button to contact the pilot diaphragm valve to open the diaphragm filling valve to refill the toilet cistern. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a Divisional of U.S. patent application Ser. No. 12/825,066, filed on Jun. 28, 2010, which is a Divisional of U.S. patent application Ser. No. 11/731,223, filed on Mar. 30, 2007.
BACKGROUND
[0002] Thermally controlled optical filters may inadvertently provide thermal cross talk between the temperature of the filter and other sources of temperature variation, for example from the case in which the optical filter is disposed, from the substrate on which the optical filter is mounted, for from another filter disposed proximate to the filter. Furthermore, varying stresses may be imparted on the filter for example via coefficient of thermal expansion (CTE) mismatches and process variations, which may impact the stability of the filter and the reliability of the frequency at which the filter operates to select a desired wavelength of laser light.
DESCRIPTION OF THE DRAWING FIGURES
[0003] Claimed subject matter is particularly pointed out and distinctly claimed in the concluding portion of the specification. However, such subject matter may be understood by reference to the following detailed description when read with the accompanying drawings in which:
[0004] FIG. 1 is diagram of thermally controlled optical filters in accordance with one or more embodiments;
[0005] FIG. 2 is a diagram of thermally controlled optical filters including a resistive temperature device formed as a generally L-shaped frame in accordance with one or more embodiments;
[0006] FIG. 3 is a diagram of a thermally controlled optical filter including a resistive temperature device formed as a generally L-shaped frame having a generally circular fillet in accordance with one or more embodiments;
[0007] FIG. 4 is a diagram of resistive temperature devices formed in L-shaped frames bonded to an optical filter wafer in accordance with one or more embodiments; and
[0008] FIG. 5 is a diagram of a thermally controlled optical filter including a resistive temperature device formed in a generally square shaped frame in accordance with one or more embodiments.
[0009] It will be appreciated that for simplicity and/or clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, if considered appropriate, reference numerals have been repeated among the figures to indicate corresponding and/or analogous elements.
DETAILED DESCRIPTION
[0010] In the following detailed description, numerous specific details are set forth to provide a thorough understanding of claimed subject matter. However, it will be understood by those skilled in the art that claimed subject matter may be practiced without these specific details. In other instances, well-known methods, procedures, components and/or circuits have not been described in detail.
[0011] In the following description and/or claims, the terms coupled and/or connected, along with their derivatives, may be used. In particular embodiments, connected may be used to indicate that two or more elements are in direct physical and/or electrical contact with each other. Coupled may mean that two or more elements are in direct physical and/or electrical contact. However, coupled may also mean that two or more elements may not be in direct contact with each other, but yet may still cooperate and/or interact with each other. Furthermore, the term “and/or” may mean “and”, it may mean “or”, it may mean “exclusive-or”, it may mean “one”, it may mean “some, but not all”, it may mean “neither”, and/or it may mean “both”, although the scope of claimed subject matter is not limited in this respect.
[0012] Referring now to FIG. 1 , a diagram of thermally controlled optical filters in accordance with one or more embodiments will be discussed. As shown in FIG. 1 , a thermally controlled optical filter may generally comprise a hot plate type structure, for example a micromachined silicon filter 108 having an optical etalon 112 disposed thereon. Filter 110 may include a resistive temperature device (RTD) 118 and heater 116 that may be utilized to heat etalon 112 to an operational temperature and to take temperature measurements of the temperature of etalon 112 to select and control the temperature of etalon 112 , for example in a feedback arrangement. Etalon 112 may comprise glass or a similar material and may be utilized to filter laser light from a laser (not shown) to tune the laser to a desired operational wavelength. In one or more embodiments, such a laser may comprise, for example, an external cavity laser. Such tuning of the wavelength of laser light passing through etalon 112 may be at least partially accomplished via controlling the temperature of etalon 112 , however the scope of the claimed subject matter is not limited in this respect.
[0013] In one or more embodiments, optical filter 110 may comprise etalon 114 adhered to glass plate 122 which in turn may be adhered to resistive temperature device and heater 118 . Etalon 114 may be adhered to glass plate 122 and/or glass plate 122 may be adhered to micro hot plate 120 having a resistive temperature device 118 and heater 116 , for example using an epoxy or similar type of adhesive, although the scope of the claimed subject matter is not limited in this respect.
[0014] Optical filter 110 may provide thermal isolation as well as mechanical isolation of resistive temperature device 118 and heater 116 . Such an arrangement may generally provide minimal cross-talk between the temperature of filter 110 and any external thermal load, for example case temperature and/or substrate temperature. Optical filter 110 may provide a simpler arrangement for controlling the temperature of etalon 114 resulting in a simpler assembly and manufacturing process. In such an arrangement, any increased cross talk between the temperature of optical filter 110 and the temperature of the case and other filters and/or the sled temperature may be addressed as described herein. Furthermore, any strain on resistive thermal device 118 and heater 116 induced by coefficient of thermal expansion (CTE) type effects and/or processing condition, for example due to relaxation of such strain over time, and any resulting error in temperature measurements, likewise may be addressed as described herein.
[0015] Referring now to FIG. 2 , a diagram of optically controlled optical filters including a resistive temperature device formed as a generally L-shaped frame in accordance with one or more embodiments will be discussed. As shown in FIG. 2 , optical filter 210 may be constructed to include resistive thermal device 118 comprising a generally L-shaped frame 212 . Such an L-shaped frame may provide a more precise measurement of the temperature of etalon 114 and further may provide reduced cross talk and/or reduced processing stress on resistive thermal device 118 due to, for example, coefficient of thermal expansion (CTE) mismatch and process type effects. In one or more embodiments, L-shaped frame 212 may comprise a highly thermally conductive material including but not limited to silicon (Si), tungsten copper (WCu), silicon carbide (SiC), and so on. L-shaped frame 212 may be disposed on micro hot plate 120 with heater 116 wherein an electrical connection between resistive thermal device 118 and micro hot plate 120 with heater 116 may be coupled, for example, using solder or wirebond. Such an L-shaped frame 212 for resistive thermal device 118 may be compatible with thin film processes to ad platinum/titanium (Pt/Ti) traces on resistive thermal device 118 in addition to one or more gold pads for solder or wirebond type connections. In one embodiment, L-shaped frame 212 may be arrived at via a dry etched process such as L-shaped frame 212 of optical filter 210 , or alternatively L-shaped frame 212 of optical filter 214 may be arrived at, for example, via a wet etched process of silicon. In one or more embodiments, L-shaped frame 212 may comprise fillet 218 having one or more surfaces disposed at right or nearly right angles, and in one or more alternative embodiments, L-shaped frame 212 may comprise fillet 220 having one or more beveled or trapezoidal type surfaces, although the scope of the claimed subject matter is not limited in these respects. In one or more embodiments, etalon 114 may include an area 216 through which laser light may pass there through proximate to fillet 218 or fillet 220 , although the scope of the claimed subject matter is not limited in these respects.
[0016] Referring now to FIG. 3 , a diagram of a thermally controlled optical filter including a resistive temperature device from as a generally L-shaped frame having a generally circular fillet in accordance with one or more embodiments will be discussed. As shown in FIG. 3 , L-shaped frame 212 may comprise a generally circular fillet 310 . In such an embodiment, circular fillet 310 may maximize, or nearly maximize, the contact area between L-shaped frame 212 and etalon 114 while reducing or eliminating clipping of the laser beam passing through area 216 of etalon 114 , although the scope of the claimed subject matter is not limited in this respect.
[0017] Referring now to FIG. 4 , a diagram of resistive temperature devices formed in L-shaped frames bonded to an optical filter wafer in accordance with one or more embodiments will be discussed. As shown in FIG. 4 , L-shaped frames 212 may be processed using a standard type micromachined silicon technology or the like. In one or more embodiments, L-shaped frames 212 of resistive thermal devices 118 may be etched and then bonded to a wafer of etalons 114 prior to dicing and then subsequently diced to arrive at optical filter subassemblies. Further as shown in FIG. 4 , in one embodiment L-shaped frames 212 may be formed via a dry etched wafer 410 or alternatively via a wet etched wafer 114 , although the scope of the claimed subject matter is not limited in these respects.
[0018] Referring now to FIG. 5 , a diagram of a thermally controlled optical filter including a resistive temperature device formed in a generally square shaped frame in accordance with one or more embodiments will be discussed. As shown in FIG. 5 , a thermally controlled optical filter may be constructed with a square-shaped frame 510 rather than with an L-shaped frame 212 . In such an arrangement, square-shaped frame 510 may include a circular opening 512 having resistive thermal device 118 disposed along a circumference of circular opening 512 . In one or more embodiments, square-shaped frame 510 may include circular opening 512 having resistive thermal device 118 disposed along a circumference of circular opening 512 and may further include a heater 514 also disposed along a circumference of circular opening 512 . It should be noted that L-shaped frame 212 and square-shaped frame 510 are merely example frames that may include resistive thermal device 118 and/or heater 116 , wherein other shapes of frames likewise may be utilized, and the scope of the claimed subject matter is not limited in these respects.
[0019] Although the claimed subject matter has been described with a certain degree of particularity, it should be recognized that elements thereof may be altered by persons skilled in the art without departing from the spirit and/or scope of claimed subject matter. It is believed that the subject matter pertaining to thermal control of optical filter with local silicon frame and/or many of its attendant utilities will be understood by the forgoing description, and it will be apparent that various changes may be made in the form, construction and/or arrangement of the components thereof without departing from the scope and/or spirit of the claimed subject matter or without sacrificing all of its material advantages, the form herein before described being merely an explanatory embodiment thereof, ad/or further without providing substantial change thereto. It is the intention of the claims to encompass and/or include such changes. | Briefly, in accordance with one or more embodiments, a thermally controlled optical filter comprises a frame coupled to an etalon where the frame includes a resistive thermal device disposed on the frame to obtain thermal measurements of the etalon during operation. The frame may be generally L-shaped or generally square-shaped. The frame may include a fillet that is generally planar, generally beveled or trapezoidal, or generally circular in shape. A heater may be additionally disposed on the frame. The etalon and frame subassembly may be bonded to a micro hot plate that is capable of heating the etalon to an operational temperature. | 8 |
FIELD OF TECHNOLOGY
The present invention relates to materials of a low dielectric constant and methods of manufacturing the materials, and more particularly, to a copolymer produced by a reaction between DCPD-containing benzoxazine (DCPDBz) and cyanate ester resin and suitable for use in material for making electronic components.
BACKGROUND
According to the prior art, when integrated circuit components are downsized to achieve a maximum of 0.25μ in the least metal-metal pitch attained by multilayer metal conducting wire manufacturing process technology, the time delay caused by interconnect becomes a major factor in component operation speed, unit area capacity, reliability, and yield. The time delay caused by interconnect equals the product of the resistance of the metal conducting wires and the capacitance of the dielectric layer between the metal conducting wires. Hence, to reduce the time delay caused by interconnect, it is practicable to use a metal of a low resistance or use a material of a low dielectric constant to make the dielectric layer between a metal and another metal.
The silicon dioxide for use in a conventional manufacturing process has a dielectric constant of 3.9 and thus meets the related requirements of a 0.35μ manufacturing process. However, a less-than-0.35μ manufacturing process requires a dielectric layer material of a much lower dielectric constant. Since organic polymeric dielectric materials seldom have a lower dielectric constant than inorganic silicon dioxide and silicon nitride do, organic polymeric dielectric materials are more suitable for use in making metal dielectric layers between multilayer interconnects than inorganic dielectric materials are. In view of this, the present invention provides a novel low dielectric constant material and its manufacturing method.
Dicyclopentadiene (DCPD) is produced when cyclopentadiene undergoes Diels-Alder reaction and thus has an aliphatic structure, high hydrophobicity, and a low dielectric constant materials. A lot of academics and manufacturers introduce DCPD into electronic materials to reduce the dielectric constants thereof. For instance, when catalyzed by aluminum trichloride, it is feasible for DCPD to react with phenol to produce DCPD-phenol oligomer whose structure is depicted as follows:
A wide variety of resins are derived from the phenolic group of the oligomer. In this regard, DIC epoxy resin (HP-7200) is typical of cyanate ester (XU-7187) of Dow-Chemical.
Ueda, an academic, discloses that the double bonds of DCPD undergo a free radical addition reaction with thiol to produce a monomer which carries a functional group, and then synthesize a sulfur-containing material suitable for use in thermoplastic injection molding, wherein the sulfur-containing material exhibits high permeability, high Abbe number, high transmittance, and high glass transition temperature (Suzuki, Y; Higashihara, T.; Ando, S.; Ueda, M. Macromolecules 2012, 45, 3402-3408.)
Wang discloses that a DCPD-phenol oligomer reacts with a phenolic group to produce a benzoxazine resin as compared to BPA-based benzoxazine and a biphenol-based benzoxazine resin. The result shows that the DCPD-based benzoxazine manifests a low dielectric constant and low hygroscopicity and thus is an advantageous material suitable for use in manufacturing advanced printed circuit boards (Hwang, H. J.; Lin, C. Y; Wang, C. S. J. Appl. Polym. Sci 2008, 110, 2413-2423.)
Cyanate ester polymers are well regarded by the electronic sector as high-performance thermosetting resins which display a high glass transition temperature, high thermal stability, low hygroscopicity, and a low dielectric constant when fully cured. The prior art disclosed a lot of novel cyanate esters which contain silicon, trifluoromethyl, phosphorus, and dipentene. Fang discloses introducing various groups into cyanate ester resins to endow them with specific functions which, together with the satisfactory thermal properties of the cyanate esters, attain high thermal stability and high performance (Fang, T.; Shimp, D. A. Prog. Polym. Sci. 1995, 20, 61-118).
In practice, Mitsubishi Gas Chemical Co., Inc. developed a line of copolymer products known as BT-resins and produced from cyanate ester (T: triazine) and bismaleimide (B: bismaleimide). BT-resins share come advantages with polyimide, that is, tolerant to heat, easy to process epoxy resins, and compatible with the other thermosetting resins, such as epoxy resins. However, the market for BT-resins is monopolized by Mitsubishi Gas Chemical Co., Inc. Hence, it is advantageous to develop novel materials with a low dielectric constant in order to circumvent related patents owned by American and Japanese manufacturing giants.
Shackled by a low curing speed and a three-dimensional reticular structure in a late curing stage, cyanate esters manifest high viscosity and thus retention of highly polar terminal group cyanate ester (—OCN), thereby leading to an increase in their dielectric constant. As early as the time when aromatic cyanate esters were developed, academics discovered that cyanate ester (—OCN) reacts with phenol (Ph—OH) to produce imidocarbonate (—OC═NO—). In view of this, Wang discloses reducing the retention of OCN terminal groups by bisphenol-A dicyanate (BADCY) during a polymerization process. Results of experiments conducted by Wang reveal that the reduction of highly polar —OCN terminal groups is effective in reducing the hygroscopicity and dielectric constant, albeit at the cost of some advantages of cyanate esters, including high glass transition temperature and tolerance to high temperature (Shieh, J. Y; Yang, S. P.; Wu, M. F.; Wang, C. S. J Polym Sci Part A: Polym Chem 2004, 42, 2589-2600.)
SUMMARY
In view of the aforesaid drawbacks of the prior art, it is an objective of the present invention to provide a novel compound structure, and the structure results from copolymerization of DCPD-containing benzoxazine (DCPDBz) and cyanate ester, so as to form a novel thermosetting polymer structure expressed by chemical formula (I) as follows:
wherein n denotes an integer, with 1≦n≦30, and X denotes at least one of —O—, —SO 2 —, —CH 2 —, —C(CH 3 ) 2 —, and —C(CF 3 ) 2 —.
Another objective of the present invention is to provide a method of manufacturing a copolymer of DCPD-containing benzoxazine (DCPDBz) and cyanate ester resin. The method comprises the steps of: providing DCPD-phenol oligomer, aniline, and paraformaldehyde in a first solvent to form a first solution, allowing the first solution to undergo a reaction at 110° C. for 6-12 hours, extracting and baking the first solution, precipitating and rinsing a product with a second solvent, drying the precipitated rinsed product in a vacuum oven to obtain DCPDBz, mixing a cyanate ester and the DCPDBz at 150° C., and heating the mixture up to 220° C. to produce the copolymer of the thermosetting polymeric DCPDBz and cyanate ester resin.
The oligomer of the present invention refers to any polymer with a relative molecular mass less than that of polymers but larger than that of small molecules. For example, the repeat unit of the present invention has a relative molecular mass of 10-30.
In an embodiment of the present invention, the first solvent is toluene, and the second solvent is hexane.
In an embodiment of the present invention, the mole equivalent ratio of oligomer, aniline, and paraformaldehyde of DCPD-phenol is 1:1:2.
In an embodiment of the present invention, the cyanate ester resin has a structure as follows:
wherein X denotes —O—, —SO 2 —, —CH 2 —, —C(CH 3 ) 2 —, or —C(CF 3 ) 2 —.
BRIEF DESCRIPTION
FIG. 1 is a flow chart of a method of manufacturing a copolymer of DCPD-containing benzoxazine (DCPDBz) and cyanate ester resin according to an embodiment of the present invention;
FIG. 2 is a 1H NMR spectrum of DCPDBz according to an embodiment of the present invention;
FIG. 3 are graphs of DSC of BADCY/DCPDBz dopants in different proportions according to an embodiment of the present invention;
FIG. 4 is a FT-IR spectrum of DCPDBz at different temperatures and for 20 minutes according to an embodiment of the present invention;
FIG. 5 is a FT-IR spectrum of BADCY/DCPDBz dopants in different proportions, at different temperatures, and for 20 minutes according to an embodiment of the present invention;
FIG. 6 is a FT-IR spectrum of BADCY at different temperatures and for 20 minutes according to an embodiment of the present invention; and
FIG. 7 are graphs of DMA of BADCY/DCPDBz copolymer in different proportions according to an embodiment of the present invention.
DETAILED DESCRIPTION
The implementation of the present invention is hereunder illustrated with specific embodiments, so that persons skilled in the art can gain insight into the other advantages and effects of the present invention easily.
Embodiment 1
Referring to FIG. 1 , there is shown a flow chart of a method of manufacturing a copolymer of DCPD-containing benzoxazine (DCPDBz) and cyanate ester resin according to an embodiment of the present invention. As shown in the diagram, the process flow of the method is as follows: 10.0 g of DCPD-phenol oligomer (0.5 mole equivalent), 4.656 g of aniline (0.5 mole), and 3.0 g of paraformaldehyde (1.0 mole) are provided (S 110 ) and then introduced to 200 mL of toluene (S 120 ) to form a first solution (S 130 ), and then the first solution undergoes a reaction at 110° C. and for 8 hours before being extracted and baked (S 140 ). The extraction is carried out thrice each with 1M sodium hydroxide (NaOH) and deionized water. The extract undergoes precipitation and rinsing carried out with hexane before being put in a vacuum oven to undergoing a baking process, and in consequence the DCPDBz produced has a yield of 70% or so. The reaction pathway is expressed with Formula 1, and its product analysis is depicted with FIG. 2 which is 1H NMR spectrum of the DCPDBz. The process flow of the method continues as follows: DCPDBz and cyanate ester are provided (S 150 ), mixed at 150° C. (S 160 ), and heated at three temperatures, namely 180° C., 200° C., and 220° C., successively, each for 2 hours (S 170 ), to produce a low dielectric copolymer of DCPDBz and cyanate ester resin (S 180 ).
Formula 1: Method of Producing DCPDBz
wherein the cyanate ester resin is one selected from a cyanate ester of the structure as follows:
X denotes —O—, —SO2-, —CH2-, —C(CH3)2- or —C(CF3)2-. The thermosetting polymeric low dielectric copolymer material thus produced is expressed by chemical formula (I)
wherein n denotes an integer, with 1≦n≦30, and X denotes —O—, —SO2-, —CH2-, —C(CH3)2- or —C(CF3)2-.
Embodiment 2
The molecular formulas of DCPDBz oligomer and bisphenol-A dicyanate (BADCY) are as follows:
wherein the n of DCPDBz denotes an integer, with 1≦n≦30
In this embodiment, the DCPDBz and BADCY are mixed in different proportions shown in Table 1 below.
TABLE 1
proportions in which DCPDBz and BADCY are mixed
DCPDBz
BADCY
1
100
0
2
25
75
3
50
50
4
75
25
5
0
100
The dopants of DCPDBz and BADCY are measured with differential scanning calorimeter (DSC), Fourier transform infrared spectroscopy (FT-IR), and dynamic mechanical analyzer (DMA), before and after mixing, and in different proportions. Referring to FIG. 3 , there are shown graphs of DSC of BADCY/DCPDBz dopants in different proportions according to an embodiment of the present invention. As shown in FIG. 3 , pure BADCY and DCPDBz exothermic peaks fall within a range of high temperatures, and exothermic peaks of both their dopants shift forward significantly, indicating that both DCPDBz oligomer and bisphenol-A dicyanate (BADCY) are subjected to catalysis and thus their exothermic peaks shift forward to fall within a range of low temperatures, wherein cyanate ester reacts quickly enough to reduce residual OCN groups, thereby facilitating the production of copolymers with a low dielectric constant.
Referring to FIG. 4 , FIG. 5 , and FIG. 6 , there are shown FT-IR spectra of DCPDBz, DCPDBz/BADCY dopants in the proportion of 50/50, and BADCY at different temperatures and for 20 minutes. As shown in FIG. 4 , the DCPDBz temperature-variable FT-IR shows that oxazine feature peak 944 cm-1 is gone at 200° C. As shown in FIG. 6 , the BADCY cyanate ester group (OCN) feature peak (2273 cm-1 and 2237 cm-1) is gone at 220° C. FIG. 5 shows that 50/50 dopant oxazine feature peak (944 cm-1) has dwindled greatly by 140° C. and is gone at 200° C., and shows that cyanate ester group (—OCN) 2273 cm-1 and 2237 cm-1 feature peaks are gone at 160° C., indicating that benzoxazine and cyanate ester have a catalytic effect on each other—a phenomenon which conforms with the data pertaining to DSC exothermic peaks.
Referring to FIG. 6 , the BADCY spectrum shows that Trazine (1367 cm-1 and 1569 cm-1) feature peaks grow with temperature gradually and remain intact at 300° C. Referring to FIG. 5 , 50/50 dopant Trazine 1370 cm-1 and 1569 cm-1 absorption peaks increase with temperature, with a surge followed by a diminution, indicating the participation of Trazine structure in the reaction. At last, 1682 cm-1 alkyl isocyanurate is gradually produced.
As observed by DSC and FTIR, the reaction mechanisms of the present invention are as follows:
(1) cyanate ester is subjected to phenolic catalysis to thereby speed up the formation of the triazine three-dimensional reticular structure expressed by Formula 2 below:
Formula 2
(2) the electron-donating triazine attacks the electron-withdrawing methylene group of oxazine, and then the electron-donating oxygen atom attacks the electron-withdrawing carbon atom, thereby producing alkyl isocyanurate and diphenyl ester structure, which are expressed by Formula 3 below.
Formula 3
Analysis of Thermal Properties of Copolymer
Referring to FIG. 7 , there are shown graphs of DMA of DCPDBz/BADCY copolymer in different proportions. As shown in the diagram, the copolymer exhibits a single glass transition temperature, thereby indicating that BADCY and DCPDBz react with each other to form a single phase and thus conforming with the prediction of FT-IR spectrum.
Dielectric Properties of Copolymer
Referring to Table 2 below, which shows the dielectric properties of BADCY/DCPDBz copolymer in different proportions, wherein the shown data reveals that adding a small amount of DCPDBz brings about a great decrease in the dielectric constant for the following reasons:
1. Benzoxazine speeds up the reaction of cyanate ester by catalysis and thus reduces the amount of residual terminal groups; 2. DCPDBz contains a hydrophobic DCPD with a cyclic aliphatic structure and thus exhibits very low polarity and tremendous three-dimensional hindrance, and in consequence the cured substance demonstrates a decrease in polarity in whole; 3. The ring opening process of Benzoxazine causes a decrease in the amount of highly polarized phenolic groups; and 4. The diphenyl ether produced during the reaction reduces the dielectric constant.
In addition, dielectric constant increases as the amount of the introduced DCPDBz decreases. Conversely, the amount of the introduced DCPDBz can be increased so as to decrease the dielectric constant, thereby indicating that the present invention is effective in reducing the dielectric constant.
TABLE 2
dielectric properties of
DCPDBz/BADCY copolymer in different proportions
DCPDBz/
1 GHz
100 MHz
BADCY
Dk(U) a
Df(mU) b
Dk(U)
Df(mU)
0/100
3.14 ± 0.005
7.89 ± 0.05
3.18 ± 0.004
7.24 ± 0.6
5/95
2.84 ± 0.006
6.89 ± 0.07
2.88 ± 0.006
6.78 ± 0.3
10/90
2.79 ± 0.008
6.76 ± 0.08
2.84 ± 0.008
6.83 ± 0.4
15/85
2.73 ± 0.008
6.70 ± 0.09
2.78 ± 0.008
6.38 ± 0.6
20/80
2.70 ± 0.008
6.69 ± 0.09
2.75 ± 0.009
6.47 ± 0.6
25/75
2.64 ± 0.008
6.66 ± 0.09
2.67 ± 0.009
6.35 ± 0.6
30/70
2.61 ± 0.009
6.51 ± 0.09
2.63 ± 0.009
6.26 ± 0.6
a: dielectric constant measured at 25° C., 1 GHz, and 0.1 GHz
b: dielectric loss measured at 25° C., 1 GHz, and 0.1 GHz
Accordingly, the present invention discloses a copolymer of DCPDBz and cyanate ester and a method of manufacturing the copolymer, thereby providing a novel material characterized by a low dielectric constant and adapted for use as a raw material for making a substrate carrying electronic components.
The present invention is disclosed above by preferred embodiments. However, persons skilled in the art should understand that the preferred embodiments are illustrative of the present invention only, but should not be interpreted as restrictive of the scope of the present invention. Hence, all equivalent modifications and changes made by persons skilled in the art to the aforesaid embodiments without departing from the spirit and scope of the present invention should fall within the scope of the present invention. Accordingly, the legal protection for the present invention should be defined by the appended claims. | A copolymer of DCPD-containing benzoxazine (DCPDBz) and cyanate ester resin forms a low-dielectric thermosetting polymeric material for making electronic components. A method of manufacturing the copolymer is also introduced. The method includes allowing DCPD-phenol oligomer, aniline, and paraformaldehyde to react at 110° C. for 6-12 hours before being extracted and baked to obtain DCPDBz; and mixing cyanate ester and the DCPDBz at 150° C.; heating the mixture up to 220° C. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to an improved apparatus, for carrying out treating operations on printed fabrics, which operations are frequently called "steaming" operations though improperly since they can be carried out without using steam but, for example, hot air, the improved apparatus being effective to operate, depending on the requirements, by using saturated steam or superheated steam or alternatively, hot air.
More specifically the apparatus according to the invention is of the type in which the static structure enclosing the treating environment, through which the fabric as suitably supported in laps, is conveyed, provided with a double wall and, in the gap of the double wall, with a passage through which, in the case of a high temperature treating or a saturated steam treating, the air fluid forming the treating medium or means is caused to pass from the bottom to the top so as to reach the top of the saddle roof of the structure, to descend progressively so as as to reach the base portion of the treating envoronment, the latter being at least partially opened to the outside.
Apparatus provided with the thereinabove cited structural and operational characteristics are well known in the art: (see for instance Italian patent application No. 28335 A/77 and the corresponding U.S. Pat. No. 4,186,572 which issued Feb. 5, 1980. In this issued Patent it is provided that at least a portion of the circulating air treating means or medium circulates between intermediate levels with respect to the treating environment height, the circulation being promoted and held by entraining jets of the treating means or medium, which is supplied under pressure.
SUMMARY OF THE INVENTION
The improved apparatus according to the present invention comprises, in a treating environment formed by a treating structure essentially of the type disclosed and illustrated in the same U.S. patent application mentioned hereinabove, at least an operating assembly, preferably a plurality of operating assemblies, which are preferably located in at least a portion of the vertical walls of the static structure enclosing the treating environment, the operating or operative assembly/assemblies or at least a portion of the operating assemblies comprising mechanical means, such as a fan, capable of imparting the required movement to the circulating air treating medium or fluid, and at least a heat generating or exchanging means located at a portion traversed by the circulating treating air fluid, in the interior of the operating assembly, the improved apparatus further comprising fittings, ducts and similar means for supplying the components of the operating assembly or plurality of operating assemblies.
Practically, the apparatus can be selectively operated by using different treating media and operating conditions, and by acting upon the different supplying means, i.e. in such a way as to put the supply means in an operative or inoperative position.
More specifically, to carry out treating operations by using saturated steam, the lower portion of the structure gap or interspace (that is the portion where is set, or held, in a known way, a predetermined water level is connected to a steam source, in general a boiler provided in the system, while the lower portion of the operating assembly or assemblies is connected to a water source in order to carry out the moistening of the air medium circulating through the assembly or assemblies, while the heat generating or exchanging means are maintained in an operating condition.
Alternatively, in order to carry out high temperature treatments, the heat generating or exchanging means are actuated and there is maintained the supply of steam at the base of the gap or interspace, while the moistening water supplying is stopped.
Finally, in order to carry out a treatment of the so-called hot or heated air type, all the supplies of steam and water are stopped, while the means for bringing heat to the circulating air, are maintained in an operating condition, under the control of the mechanical pushing means, (practically, as stated hereinabove, at least a fan).
From a structural or constructional point of view, the operating assembly or assemblies are materially recessed in recesses formed in the thickness of the gap provided between the vertical walls, the bottom vertical wall of the recesses, which wall being outwardly directed, is formed by portions of the double-wall static structure of the apparatus.
These recesses are separated one from another by spaces defining the gap, in such a way as to assure the continuity of the passage between the base of the walls and the portion, of the double wall type, of the essentially known static structure.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforesaid and other more specific characteristics and advantages of the present invention and possibilities afforded by an industrial application thereof, will become more apparent from the following detailed description of a non limitative exemplary embodiment of the improved apparatus, with reference to the accompanying drawings, where:
FIG. 1 is a perspective fragmentary view illustrating a portion of the apparatus, as seen from the interior, the cover of one of its operating assemblies or sets being removed in order to show the related main components;
FIG. 2 is a half cross-section of the apparatus as taken through a vertical cross plane containing one of said operating assemblies, as associated to the different supply ducts, the latter being represented schematically and including, preferably, fittings and branches for reaching the individual operating assemblies.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring specifically to the figures of the drawings, the static structure of the treating environment, as fragmentarily represented in FIG. 1, comprises a chamber provided with a saddle roof 10 and defined by side walls, 12 and front wall 14 respectively, of the double-wall type, and forming gaps or interspaces 16 and respectively 18 and 20.
In the lower portions 18' of the gap 18 are located perforated ducts 22 in which, under some treating conditions, is introduced steam which mainly arrives from the system boiler or from the overall plant, and the steam exiting the ducts 22 bubbles through water provided at suitable level at the base of said gap, as described in the patent cited hereinabove.
The double walled structures, in particular of the vertical longitudinal walls 12, are interrupted to provide recesses or cavities 24; however between the recesses are formed portions 26 (FIG. 1) along the gap in uninterrupted or continuous manner from the base 18' as far as its connection with the gap 16, in the interior of the roof 10. At the top or near the top of the roof, the gap 16 is provided with ports or openings 28 (FIG. 2) through which the steam descends into the treating chamber.
The operating assemblies or sets which are characteristic of the improved apparatus, as indicated overally at 30, are located in the recesses 24 and protected by covers 32 (a cover is removed in FIG. 1 at the assembly 30') which covers are perforated at the lower portions 34, or capable of being unobstructedly traversed by the air medium or means present in said treating environment and which is sucked by suitable fans as provided in the respective operating assemblies 30.
At the base of the assemblies new or fresh air can be sucked from the exterior, through suitable valves 38. At 40 is indicated the driving or actuating system for actuating the respective fan 36.
The operating components of each operating assembly comprise a radiator system 42 for applying thermal energy or power to the air fluid circulating through the assembly. The radiator or radiating system 42 may comprise a coil through which a fluid having the required temperature can circulate, for example high pressure steam, diathermal oil or other liquid capable of providing the required temperature. As electric power is used for heating, the system 42 may comprise electric resistances.
Each operating assembly or set is connected, preferably through fittings and manifolds, to supply systems and circuits, as it is schematically illustrated in FIG. 2.
The supply or supplying means comprise at least a duct 44 for supplying the steam V, through a sliding or interception and adjusting valve 46, to the perforated duct 22 which provided at the base 18' of the gap 18. The duct 44 comprises a branch 48, also provided with sliding and adjusting valves 50, which connects at 52 with a duct 54, provided with a related sliding and adjusting valve 56, for supplying water (H 2 O) for moistening the air fluid circulating through the assembly which is sprayed at 58, preferably at the outlet of the fan 36.
At 60 and 62 are represented, exemplary, ducts provided with valve means 64 and 66, as components for delivering and returning in the energy supplying circuit E, supplying the radiator 42, the means consisting obviously of ducts, in the case in which the radiator 42 is an exchanger unit supplied in a closed loop with a high temperature fluid or liquid, and respectively of electric wires, in the case in which the radiator 42 comprises electric resistances.
During the service period, it is obviously assumed that in the treating chamber there is present the printed fabric to be treated, as supported in laps, one whereof being indicated at 68 in FIG. 2, the laps being supported and caused to advance by cross rods 70, as it is well known in the art.
Practically the apparatus provides the means for establishing and maintain, jointly or alternatively, two circuits or loops of the air treating medium, in the interior of the environment which, communicating freely at the base with the outside, is always at atmospheric pressure.
One circuit extends in known way, in particular as described in the patent cited hereinabove, and is supplied with steam V sent at the base 18' of the gaps or interspaces 18 and 16 and introduced from the top, at 28, of the treating chamber. This steam, as it reaches its possible lower level L, is sucked, also in known way, through ducts 72 and 74 at the base of the vertical walls 12 and 14 of the treating chamber, preferably overlying channels 76 and respectively 78 (FIG. 1) for collecting the condensate descending on the inner surfaces of said walls. Accordingly this circuit is not herein described further.
The other circuit which, under some alternative conditions (or selective conditions) may exists jointly with the first one, closes in the interior of the treating chamber between intermediate levels with respect to the useful height, and, more specifically, between the top of the operating assemblies and the perforated portions 34 of the respective covers 32, the path of this latter circuit, in the treating environment being schematically indicated by the arrows F' and F" in FIG. 2.
As stated hereinabove the improved apparatus is effective, with respect to its constructional characteristics and operating means, to selectively operate according to different operating methods, as required by an industrial application, and, more specifically:
if it is desired to operate in a saturated steam environment, by operating the valve 46 steam is sent to the base 18' of the gap, in such a way as to produce saturated steam at the output of the present water and into it are immersed the ducts 22, through which saturated steam rises along the gaps and discharges from the top to the bottom at 28 at the top of the chamber.
Simultaneously the fans 36 are actuated as well as the moistening circuit 48 and 54 in such a way as to establish in the interior of the environment a recirculation F' and F" of moistened steam. This circulation is not however drastically critical and it can be omitted, if desired.
if it is desired to operate under high temperature conditions, to the circuit described hereinabove, which circuit closes through the gaps 18 and 16, is associated, between the top and the base (level L) of the treating environment, the circuit F', F" by actuating the radiators 42 for supplying energy.
finally, if it is desired to operate in heated or hot air, the supply of steam V and water H 2 O from the ducts 44 and 54 is stopped, while maintaining the fans 36 and radiators 42, in operation the circulation of the heated air, as heated by the radiators, closing at F' and F" through the operating assemblies, the possible air excess due to the introduction of fresh air at 38, discharging even in this case from the base of the chamber.
Since the structures, means and methods which are characteristic of the present invention have been described hereinabove and illustrated merely as indicative not limitative example, it should be noted that they are susceptible to many modifications and variations depending on the specific applications and service and production exigences of the apparatus.
For example, in order to increase the temperature of the steam V introduced into the apparatus, the steam can be superheated by means of superheaters 80 located and operating upstream of the duct 44. Furthermore, the temperature of the steam descending at 28 from the top of the chamber can be increased by means of radiators, such as heting coils supplied with high temperature steam, diathermal oil or the like, as well as electric resistances, located in the gaps or interspaces extending from the bottom to the top through the walls of the apparatus, the thermal energy supplying means being in turn effective to be actuated and to be put out of operation for selectively carrying out one method or the other, as well as variations.
For these reasons it should be noted that the variations indicated hereinabove as well as other possible variations and modifications are to be considered as falling within the scope of the invention as defined by the accompanying claims. | An improved apparatus for carrying out steaming or similar operations in a double-wall chamber opened at the bottom with steam passing from the bottom to the top through gaps. The apparatus, comprises operating assemblies including fans and radiators effective to cause the air treating means to circulate at intermediate levels with respect to the height of the chamber, and steam and water and power supplying means capable of being selectively operated to allow the apparatus to operate by different air treating means or media. | 3 |
RELATED APPLICATIONS
[0001] This application further claims the benefits of priority U.S. Provisional Application 61/546,017 filed on Oct. 11, 2011.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
[0002] This invention was made with government support under NIH-NINDS U01NS063555, NIH-NCRR G12RR03035 (RCMI) and NIH-NCRR 1U54RR0261393 awarded by National Institutes of Health grants. The government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to the field of medical prevention and treatment of a neuroinjury; in particular, relates to the prevention and treatment of HIV (Human immunodeficiency virus) infection and HIV-associated neurocognitive disorders (HAND).
[0005] 2. Discussion of the Background
[0006] Currently there are several antiviral drugs for the treatment of HIV/AIDS. However, one of the main problems with antiviral drugs is the mutation of the virus and the HIV virus is not an exception. Some treatments were developed to extend the life of the person infected with the virus. For example one of the treatments is called HAART (Highly Active Antiretroviral Therapy), which is a treatment to suppress HIV viral replication and the progression of HIV disease. HAART is defined as treatment that comprises at least three active anti-retroviral medications (ARV's), typically two nucleoside or nucleotide reverse transcriptase inhibitors (NRTI's) plus a non-nucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor (PI) or another NRTI called abacavir (Ziagen).
[0007] In addition there is a concern for HIV replication stimulated by inflammatory mediators, such as cytokines and chemokines. Therefore there is a major need to identify a compound that can prevent synthesis and liberation of proinflammatory cytokines and chemokines.
[0008] Further in the post-HAART era, HIV-associated neurocognitive disorders (HAND) have become the most common neurologic complication of AIDS, affecting approximately 40-60% of HIV-infected patients. HAND is an encephalopathy induced by HIV-1 infection and fueled by immune activation of T-lymphocytes and macrophages. These activated cells have the capability to enter the brain and secrete neurotoxins of both host and viral origin affecting brain cells such as glial cells and neurons. There is a major need to identify a compound that can prevent or alleviate the damaging effects following HIV-1 infection in the brain.
[0009] Several studies, as disclosed in US Patent Application 2009/0291976 and US Patent Application 2011/0015186, hereby included by reference, have identified a non-toxic compound called 4R-cembranoid (4R), a cyclic diterpenoid from the family of cembranoids, a natural product found in tobacco leaves and flowers that readily penetrates into the brain and has demonstrated anti-apoptotic, anti-inflammatory, and neuroprotective properties:
Neuroprotection: 4R protects the brain against N-methyl-D-aspartate(NMDA)-induced excitotoxicity. This was extensively studied in ex viva (brain slices) and briefly in vivo (Ferchmin et al., 2005). U.S. Pat. No. 6,204,289 B1, Issued: Mar. 20 2001 Anti-apoptotic: 4R stimulates certain NMDA receptors activating a prosurvival and anti-apoptotic process which involves increase of intracellular calcium, activation of the PI3-Kinase/Akt cascade followed by GSK-3beta inactivation (Ferchmin et al., 2005). U.S. patent application Ser. No. 12/308,293 (pending) Anti-inflammatory: 4R inhibits COX with an IC 50 lower than acetylsalicylic acid (Olsson et al., 1993).
[0013] Therefore is a need to identify a effective dose of a compound that can diminish inflammatory mediators and prevent or alleviate the damaging effects following HIV-1 infection in the brain.
SUMMARY OF THE INVENTION
[0014] The present invention has identified a non-toxic terpenoid called 4R-cembranoid (4R) that readily penetrates into the brain and has anti-apoptotic, anti-inflammatory, and neuroprotective properties. The first object of the present invention is to provide a method using an effective dose of 4R-cembranoid to suppress HIV-1 replication in T-lymphocytes by administering to a subject an amount of 4R.
[0015] Another aspect of the invention is to modulate the production of inflammatory cytokines/chemokines in these HIV-infected cells.
[0016] Another aspect of the invention is to identify the amount of 4R which is toxic to glial cells and neurons.
[0017] Another object of the invention is to diminish HIV-mediated neurotoxicity.
[0018] The invention itself, both as to its configuration and its mode of operation will be best understood, and additional objects and advantages thereof will become apparent, by the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawing.
[0019] The Applicant hereby asserts, that the disclosure of the present application may include more than one invention, and, in the event that there is more than one invention, that these inventions may be patentable and non-obvious one with respect to the other.
[0020] Further, the purpose of the accompanying abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The accompanying drawings which are incorporated herein constitute part of the specifications and illustrate the preferred embodiment of the invention.
[0022] FIG. 1 shows the chemical structure of the 4R-Cembranoid in accordance with the principles of the present invention.
[0023] FIG. 2 shows graphical results of 4R decreasing HIV-1 virus replication in Peripheral Blood Mononuclear Cells (PBMC).
[0024] FIG. 3 shows graphical results of 4R decreasing the replication of two AZT-resistant HIV-1 virus strains in Peripheral Blood Mononuclear Cells (PBMC).
[0025] FIG. 4 shows graphical results of 4R decreasing HIV-1 virus replication in human microglial cells.
[0026] FIG. 5 shows graphical results of 4R decreasing HIV-1 virus replication in human microglial cells in the presence or in the absence of interferon-g (IFN-g).
[0027] FIG. 6 shows graphical results of 4R preventing the HIV-1 virus-induced neurotoxicity.
[0028] FIG. 7 shows graphical results for the lack of toxicity of 4R to microglia and astrocyte cells.
[0029] FIG. 8 shows graphical results of the lack of toxicity of 4R to neurons, in the presence or absence of HIV-1 virus.
[0030] FIG. 9 shows graphical results of 4R decreasing the liberation of pro-inflammatory chemokines RANTES and MIG from PBMCs infected with HIV-1 virus.
[0031] FIG. 10 shows graphical results of 4R decreasing the liberation of pro-inflammatory cytokines TNF-α and IP10 from PBMC infected with HIV- 1 virus.
[0032] FIG. 11 shows graphical results of 4R decreasing the liberation of pro-inflammatory cytokines IL-1b from PBMC infected with HIV-1 virus.
[0033] FIG. 12 shows graphical results of 4R decreasing the liberation of pro-inflammatory cytokines IL-6 and TNF-α from PBMC infected with HIV-1 virus.
[0034] FIG. 13 shows graphical results of 4R penetrating and accumulating in the brain, where it will exert its neuroprotective activity.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] The accompanying drawings which are incorporated herein constitute part of the specifications and illustrate the preferred embodiment of the invention.
[0036] FIG. 1 shows the general. Structure of the present invention chemical formula 4R-cembranoid.
[0037] FIG. 2 is directed to the effect of 4R treatment on HIV viral load in acutely HIV-1 infected peripheral blood mononuclear cells (PBMC). PBMC from healthy donors were infected with HIV-1 SF2 for 6 days. Before infection cells were pre-treated with 4R (10 pM) for 24 hours. After pretreatment, PBMC were infected with HIV-1 SF2 and 24 hours later, 4R (10 pM) was added. Subsequently, the cells were treated with 4R every 72 hours. Control cultures received 4R vehicle, dimethyl sulfoxide (DMSO) at the same times. Viral load was measured by RT-PCR method (Reverse transcription polymerase chain reaction).
[0038] The results show that with human PBMC acutely infected with HIV-1 virus, ( 10 μM) 4R decreased HIV-1 virus replication to 28% of the control value obtained in the absence of 4R.
[0039] FIG. 3 is directed to the effect of 4R treatment on the replication of two AZT-resistant HIV-1 virus strains in
[0040] Peripheral Blood Mononuclear Cells (PBMC). Approximately 2.0×10 6 PBMC were infected with the HIVSF2 strain and two AZT-resistant HIV-1 strains (MDR769 and MDR807) for 24 hours. After washing with medium, the cells were treated with various 4R concentrations. At 6 days post-infection, HIV p24 levels were measured. The data shown represent experiments performed in quadruplicate.
[0041] The results show that 4R inhibited close to 90% of the HIV p24 of the infected cells compared to infected cells alone.
[0042] FIG. 4 is directed to the effect of 4R treatment on HIV viral load in acutely HIV-1 infected human microglial cells. Approximately 1.0×10 6 human microglia cells were infected with long of HIV-1 Bal for 24 hours. After washing with medium, the cells were treated with 40 μM of 4R compound. At 6 days post-infection, HIV p24 levels were measured. The data shown represent three independent experiments performed in quadruplicate.
[0043] The results show that 4R inhibited 60% of the HIV p24 of infected cells compared to the vehicle control.
[0044] FIG. 5 is directed to the effect of 4R treatment on HIV viral load in acutely HIV-1 infected human microglial cells, in the presence of interferon-g (IFN-g). Approximately 1.0×10 6 human microglia cells were infected with long of HIV-1 Bal for 24 hours. After washing with medium, the cells were treated with interferon-g (IFN-g) in the absence and in the presence of 40 μM of 4R compound. At days post-infection, HIV p24 levels were measured. The data shown represent three independent experiments performed in quadruplicate.
[0045] The results show that, in the presence of IFN-g, 4R inhibited 75% of the HIV p24 of infected cells compared to the IFN-g control.
[0046] FIG. 6 discloses the effect of supernatants from HIV-infected human glia cells and PBMC, in the presence or absence of 4R, added to a human neuronal cell line for 48 hours. Neurons viability was measured by MTT. Supernatants from cells infected with HIV-1 virus decreased neuronal survival by approximately 20% - 40% (compare first and second bar in each set as shown in FIG. 6 ). On the other hand, supernatants from not infected cells not treated and treated with 10 μM 4R had no effect on neuronal viability (compare first and third bar in each set as shown in FIG. 6 ). Finally, supernatants from cells infected with HIV-1 virus and treated with 10 μM 4R did not display increased neuronal death (compare first and last bar in each set as shown in FIG. 6 ).
[0047] The results show that 4R prevented the HIV-1 virus induced neurotoxicity.
[0048] FIG. 7 is directed to human microglia and astrocyte cell lines treated for six days with 4R at various concentrations (1-100 μM). The number of cell remaining in the well at day 6 was measured by applying colored solutions to the cells in order to quantify cells by measuring them at a certain wavelength by a spectrophotometer. For example a MTT (3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) reagent which produces a blue color proportional to the number of live cells. The color is measured as optical density (O.D.) at the wavelength of 560 nm.
[0049] The results show that 4R is not toxic to these cell lines up to a concentration of 100 μM.
[0050] FIG. 8 is directed to human neuronal cell line infected with HIV-1 SF2 and treated for six days with 10 μM 4R. The number of cells remaining in the well at day 6 was measured with the MTT reagent which produces a blue color proportional to the number of live cells. The color is measured as optical density (O.D.) at the wavelength of 560 nm.
[0051] The results show that 10 μM 4R is not toxic to neurons in the presence or in the absence of HIV-1 virus. Note that the virus itself was not toxic to neurons which do not have a receptor for this virus and subsequently neurons cannot be infected by HIV-1 virus. The neurotoxic effects observed in other experiments are due to neurotoxins produced by HIV-1 infecting PBMC, astrocytes or microglia.
[0052] FIG. 9 is directed to the effect of 4R on RANTES and MIG chemokines production in acutely HIV-1 infected PBMC. The PBMC were infected with HIV-1 SF2 for 6 days. Before infection cells were pre-treated with 4R (10 μM) for 24 hours; 4R (10 μM) was also added 24 hours after infection and at day 3. Control cultures received 4R vehicle (DMSO) at the same times. Cytokine release was measured by cytometric bead array (CBA).
[0053] The results show that with human PBMC acutely infected with HIV-1 virus, an amount of at least 10 μM 4R decreased the liberation of pro-inflammatory chemokines RANTES and MIG to approximately 50% of the control value obtained in the absence of 4R.
[0054] FIG. 10 is directed to the effect of 4R on TNF-α and IP-10 cytokines production in acutely HIV-1 infected PBMC.
[0055] PBMC were infected with HIV-1 SF2 for 6 days. Before infection cells were pre-treated with 4R (10 μM) for 24 hours; 4R (10 μM) was also added 24 hours after infection and at day 3. Control cultures received 4R vehicle (DMSO) at the same times. Cytokine release was measured by cytometric bead array (CBA).
[0056] The results show that with human PBMC acutely infected with HIV-1 virus, an amount of at least 10 μM 4R decreased the liberation of pro-inflammatory cytokines TNF-α and IP-10 to less than 50% of the control value obtained in the absence of 4R. This finding is very important since these two cytokines are closely associated with up-regulation of HIV-1 replication. Therefore, one mechanism by which 4R suppresses viral replication is by down-regulating the production of these pro-inflammatory cytokines.
[0057] FIG. 11 is directed to the effect of 4R on cytokine IL-1b production in acutely HIV-1 infected PBMC. Approximately 2.0×10 6 PBMC were infected with HIVSF2 strain for 24 hours. After washing with medium, the cells were treated with 10 μM 4R. At 6 days post-infection, supernatants were collected and subjected to inflammatory cytokine measurement using cytometric bead array (CBA).
[0058] The results showed that 4R inhibited the inflammatory cytokines IL-1b by 60%. This is important because the production of inflammatory cytokines is closely associated to HIV-1 replication and brain damage.
[0059] FIG. 12 is directed to the effect of 4R on cytokines IL-6, and TNF-α production in acutely HIV-1 infected PBMC. Approximately 2.0×10 6 PBMC were infected with HIVSF2 strain for 24 hours. After washing with medium, the cells were treated with 20 μM 4R. At 6 days post-infection, supernatants were collected and subjected to inflammatory cytokine measurement using cytometric bead array (CBA).
[0060] The results showed that 4R inhibited the inflammatory cytokines IL-6 and TNF-α to 40% and 30% of control, respectively. This is important because the production of inflammatory cytokines is closely associated to HIV-1 replication and brain damage.
[0061] FIG. 13 is directed to plasma and brain 4R levels in male Sprague-Dawley rats. Rats were administered 6 mg/kg 4R by either intravenous (iv) or intramuscular (im) routes. Blood was collected at several time points through 8 hr after administration and brains were collected at 2 time points. 4R levels were determined using an LC-MS/MS method. Values represent the mean±SD of 3 rats.
[0062] The results show that just 10 min after injection, 4R was found in brain at higher concentration than those seen in blood. Therefore, 4R penetrates into and accumulates in the brain where it can fulfill its neuroprotective activity.
[0063] Other methods to administrate 4R cembranoid to the subject are by intranasal route and by oral route. For intranasal route 4R cembranoid is administered to the subject in a dose range of 1 mg/kg to 90 mg/kg body weight. On the other hand for oral route 4R cembranoid is administered to the subject b in a dose range of 1 mg/kg to 120 mg/kg body weight.
[0064] Our results demonstrate that 4R was not toxic to glial cells at a concentration of 1-100 μM and to neurons at a concentration of 10 μM. Furthermore, 4R suppressed HIV-1 replication in T-lymphocytes and downregulated the inflammatory chemokines RANTES and MIG, and the inflammatory cytokines TNF-α and IP-10. In accordance with the principles of the present invention it is disclosed a method for using the compound 4R to prevent or alleviate the damaging effects following HIV-1 infection in the brain, more particularly the mechanisms involved in the pathogenesis of HAND by which this compound may elicits its properties. Further it is disclosed the mechanism by which 4R exerts its effect on lymphocytes and brain cells which leads to the development of therapy for treating HIV-1-induced encephalopathy.
[0065] The invention is not limited to the precise configuration described above. While the invention has been described as having a preferred design, it is understood that many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art without materially departing from the novel teachings and advantages of this invention after considering this specification together with the accompanying drawings.
[0066] Accordingly, all such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by this invention as defined in the following claims and their legal equivalents. In the claims, means-plus-function clauses, if any, are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures.
[0067] All of the patents, patent applications, and publications recited herein, and in the Declaration attached hereto, if any, are hereby incorporated by reference as if set forth in their entirety herein. All, or substantially all, the components disclosed in such patents may be used in the embodiments of the present invention, as well as equivalents thereof. The details in the patents, patent applications, and publications incorporated by reference herein may be considered to be incorporable at applicant's option, into the claims during prosecution as further limitations in the claims to patentably distinguish any amended claims from any applied prior art. | A method and composition for suppressing replication of the HIV-1 virus strains, modulating the production and liberation of inflammatory mediators; and the prevention and treatment of neurocognitive disorders. The method comprises administering to a subject an effective amount of an a macrocyclic diterpenoid, such as 4R cembranoid. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Divisional of co-pending application Ser. No. 13/971,094, filed on 20 Aug. 2013, for which priority is claimed under 35 U.S.C. §120; and this application claims priority of Application No. 1214823.5 filed in United Kingdom on Aug. 20, 2012 under 35 U.S.C. §119, the entire contents of all of which are hereby incorporated by reference.
FIELD OF THE INVENTION
This invention relates to a tamper indication device and in particular to a stackable security wrap for an electronic circuit to protect against tampering.
Although this invention will be described in relation to security wraps for a printed circuit board as an example of the invention, the invention can be used with any printed electronics (PE) flex having a need for protection against or detection of tampering.
BACKGROUND OF THE INVENTION
Traditional security wraps form a solid security screen masking an area of the electronics to be protected. Removal of the security wrap is physically difficult due to the manner in which the security wrap is attached to the device, usually by gluing, soldering or encapsulation by a resin material. Modern security wraps have a security screen electrically connecting a pair of terminals of an alarm circuit. The security screen may be damaged or broken during attempts to tamper with the device to thereby set off an alarm condition. The alarm circuit may disable the device or simply give a visual indication that the security wrap has been tampered with.
In a co-pending commonly assigned patent application, there is disclosed a security wrap of the breakable conductor type, having a security screen with a conductor that is relatively thin and densely packed over the area to be protected to prevent tampering and arranged or designed to easily fracture should an attempt be made to tamper with the security wrap once fitted. However, security wraps are often required to cover complex shapes which may be best protected by using two or more security wraps. With only a limited number of alarm terminals available, connection of the security screens of multiple security wraps may be problematic.
Hence, there is a desire for a security wrap which can be stacked with another security wrap with the security screens of the two security wraps being electrically interconnected.
SUMMARY OF THE INVENTION
Accordingly, in one aspect thereof, the present invention provides a security assembly for protecting a device, comprising first and second security wraps fitted to the device. The first security wrap covers a first area of the device, and has a first security screen comprising a pair of first screen terminals and a conductive track extending between said first screen terminals. The second security wrap partially overlaps said first security wrap, covers a second area of the device, and has a second security screen comprising a pair of second screen terminals and a conductive track extending from said second screen terminals. A conductive structure is disposed in an overlapping area between said first security wrap and said second security wrap and coupled to said screen terminals of said first security screen and to said screen terminals of said second security screen.
Preferably, said first screen terminals of said first security screen and said second screen terminals of said second security screen are coupled to two corresponding terminals of an alarm circuit of the device.
Preferably, said first security wrap further includes a first substrate; said first security screen includes said first screen terminals and said conductive track formed on said first substrate; and said conductive structure includes a conductive plug formed in said first substrate and coupled to said first screen terminals of said first security screen and to said second screen terminals of said second security screen.
Optionally, said conductive structure includes a conductive resilient disc disposed between said first security wrap and said second security wrap, said conductive resilient disc being in contact with said first screen terminals of said first security screen and with said second screen terminals of said second security screen in response to a compression in the overlapping area between said first security wrap and said second security wrap.
Optionally, an adhesive layer in the overlapping area between said first security wrap and said second security wrap, said adhesive layer compressing said conductive resilient disc in contact with said first screen terminals of said first security screen and with said second screen terminals of said second security screen.
Optionally, further comprising a spigot over the overlapping area between said first security wrap and said second security wrap, said spigot compressing said conductive resilient disc in contact with said first screen terminals of said first security screen and with said second screen terminals of said second security screen.
Optionally, said conductive structure includes a carbon pad disposed in the overlapping area between said first security wrap and said second security wrap and in contact with said second screen terminals of said second security screen; said carbon pad and said first screen terminals of said first security screen define a gap there between; and said carbon pad is in contact with said first screen terminals of said first security screen in response to a compression of the overlapping area between said first security wrap and said second security wrap.
Preferably, said conductive structure includes a printed conductive through hole electrically connected to said first screen terminals of said first security screen and said second screen terminals of said second security screen.
Preferably, said second security wrap includes a folded wrap.
Preferably, said first and second security screens include first and second breakable conductive tracks formed on said first and second security wraps, respectively.
According to a second aspect thereof, the present invention provides a security assembly for protecting a device includes first and second wrap. The first wrap comprises a substrate having first side and second sides opposite to each other, a first conductive track bonded to the first side of said substrate and having two ends forming first screen terminals coupled to the device and second screen terminals, and a first adhesive layer covering said first conductive track over the first side of said substrate and bonding said substrate to the device. The second wrap has an overlapping area with said first wrap and comprises a substrate having first and second sides opposite to each other, a second conductive track bonded to the first side of said substrate and having two ends forming second screen terminals coupled to the first screen terminals of said first conductive track and second screen terminals coupled to the device, and a second adhesive layer covering said second conductive track over the first side of said substrate and bonding the substrate to the device. A conductive structure is disposed in the overlapping area between said first wrap and said second wrap and in said substrate of said first wrap, said conductive structure being coupled to said first screen terminals of said first conductive track and to said second screen terminals of said second conductive track.
Preferably, said first and second conductive tracks includes first and second breakable conductive tracks.
Preferably, further comprising an intermittent pattern of release ink disposed between the first side of said substrate of said first wrap and said first conductive track to selectively modify a bonding strength between said first conductive track and said substrate of said first wrap.
Preferably, said first screen terminals of said first conductive track are coupled to third terminals of the alarm circuit of the device; said second screen terminals of said second conductive track coupled to third terminals of the alarm circuit of the device; said first conductive track and said second conductive track form a series conductive path between the first and second terminals of the device.
Preferably, said first wrap is fitted to the device and covers a first area of the device; and said second wrap is fitted to the device and covers a second area of the device.
By overlaying and interconnecting security wraps, complex areas can be covered or protected by the security wraps without having to form large complex security wraps which have high material wastage.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will now be described, by way of example only, with reference to figures of the accompanying drawings. In the figures, identical structures, elements or parts that appear in more than one figure are generally labelled with a same reference numeral in all the figures in which they appear. Dimensions of components and features shown in the figures are generally chosen for convenience and clarity of presentation and are not necessarily shown to scale. The figures are listed below.
FIG. 1 illustrates an exemplary PCB, protected by two interconnected security wraps;
FIG. 2 is an exploded view of the device of FIG. 1 ;
FIG. 3 illustrates a folded security wrap, being one of the security wraps shown in FIG. 1 ;
FIG. 4 illustrates the security wrap of FIG. 3 before it is folded into its final form;
FIG. 5 is a sectional schematic of the electrical connection between the two security wraps;
FIG. 6 is an enlarged view of a connection shown in FIG. 5 ; and
FIGS. 7 & 8 illustrate alternative connection methods.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 and 2 illustrate an electronic device 10 , by way of example only, in the form of a printed circuit board (PCB) 12 having electronic components such as a CPU 14 that is desired to be protected against tampering. The PCB 12 also has a key pad having a number of keys represented as circles 16 on the lower section of the PCB 12 , for entering data and instructions for the CPU 14 . Two security wraps 20 , 30 are fitted to the PCB 12 . A first security wrap 20 covers the key pad portion of the PCB 12 . It may also cover smaller electronic components. A second security wrap 30 covers the CPU 14 and larger electronic components. To accommodate the CPU 14 , which is too large to be securely covered by a flat security wrap, the second security wrap 30 is of the folded type wherein the wrap 30 is folded to form a chamber for the CPU 14 . Alternatively, the second security wrap 30 may be an embossed security wrap having a preformed chamber to accommodate the CPU 14 . Preferably the second security wrap 30 is mounted to the first security wrap 20 as this allows a more simple assembly and construction of the first security wrap 20 . Each security wrap 20 , 30 has a conductive circuit 22 , 32 between a pair of screen terminals 24 , 34 forming a security screen. The screens, in use, form a conductive path between terminals 18 of an alarm circuit. When the electrical connection between the alarm terminals 18 is interrupted, such as when the conductor of a screen is broken or the security wrap is removed, an alarm condition is triggered. The response to the alarm condition depends on the device but may include shutting down of the device, resetting the memory of the CPU, disabling or total destruction of the device.
The PCB 12 and the two security wraps 20 , 30 are shown in exploded view in FIG. 2 . As can be seen, two conductive spring discs 56 , known as domes, are used to electrically connect the security screens of the security wraps 20 , 30 together. It is preferable for the security screens to be connected in series so that to the alarm circuit, the two security screens appear and function as a single security screen. A pair of third terminals 36 is shown formed on the second wrap 30 . The third terminals 36 are arranged to connect to the alarm terminals 18 and form the ends of the conductive path formed by the screens. As will be realized, for the third terminals 36 to be the ends of the conductive path, the second wrap 30 must have two security screens, one screen extending between one of the third terminals 36 to one of the second terminals 34 and the other screen extending between the other third terminal 36 and the other second terminal 34 . Alternatively the third terminals 36 could be formed on the first wrap 20 . This depends on the layout and location of the terminals of the alarm circuit and the layout of the wraps. It is also possible for each wrap to have one third terminal and one first or second terminal such that each wrap has only one conductive screen. This has the advantage of requiring only one through connection to be formed in the first substrate.
As mentioned, the second security wrap 30 is preferably formed as a folded wrap. This means that the wrap 30 is formed from a flat sheet of flexible substrate material. Once the flat wrap has been formed and cut to shape, it is folded into the desired shape. The unfolded or developed state is shown in FIG. 4 . Fold lines are indicated by dashed lines 41 . The security screen 32 is also partially indicated by a dashed line. In practice, the security screen 32 covers substantially the entire under surface of the substrate which is then covered with an adhesion to fix the wrap 30 to the device. As can be seen, the pre-folded wrap has a central portion 40 , four side portions 42 extending from the central portion 40 across fold lines. Panels 46 extend from each side portion 42 across a fold line. The two longer side portions 42 also have two flaps 44 extending from the short edges. When folded, the flaps 44 lay over the adjacent shorter side portion 42 and are fixed thereto by adhesive. Panels 46 are turned out to form a rim that is arranged to be fixed to the PCB 12 , with one panel slightly raised to sit on the first security wrap 20 and thus is fixed to the PCB 12 via the first security wrap 20 whereas the other panels, in the embodiment shown, are fixed directly to the PCB 12 .
The general principles of construction of a security wrap will now be described with reference to the first security wrap 20 and FIG. 6 . The security wrap has a substrate 50 , a conductive circuit 22 , and a layer of adhesive 54 to bond the security wrap to the parent device, i.e., to PCB 12 . An insulating layer, such as a dielectric layer, may be used to provide insulation between the conductive circuit 22 and the adhesive or device. The adhesive, if non-conductive, may function as the insulating layer.
For a security wrap 20 with breakable conductors, an intermittent layer of adhesive modifier or release layer 52 is applied between the substrate 50 and the first conductive circuit 22 . It should be noted that the use of breakable conductors is optional and that breakable conductors can be formed using a different method not involving a release layer.
The substrate 50 is preferably a polymer film, typically a polyethylene terephthalate (PET or commonly referred to as polyester) film, that provides a base for a security wrap circuit. Optionally the substrate is flexible, being a film of thickness between 25 μm and 175 μm but can be greater depending on functional requirements and may include other variants of polymer film including, but not limited to, polycarbonate, PEN, polyimide and PVC. The substrate 50 may be clear but preferably is opaque and pigmented, for example black or white, to hide the configuration of the conductive screen 22 and the underlying circuitry on PCB 12 .
The release layer 52 is preferably, a ultra-violet (UV), infra-red (IR) or thermally cured ink system used to provide a different adhesion level between the substrate 50 and the security screen 22 . The ink is thus an adhesion modifier. The release layer 52 is intermittent and applied to the substrate 50 in a predetermined pattern by a printing process and is not a complete layer such that there are areas of substrate which are not covered by the adhesion modifier ink. Optionally, the pattern of the release layer 52 is simple stripes or dots.
The conductive circuit 22 is composed of a pattern formed by a conductive trace or conductor preferably formed by thermoset or thermoplastic conductive ink printed over the substrate 50 in variable trace widths and serpentine mesh patterns forming an electrically conductive path between a pair of screen terminals 24 . Preferably, the screen terminals 24 are simply the ends of the conductors.
The conductive inks can be silver, silver-coated copper or gold containing conductive or resistive ink, each with specific properties that suit the necessary requirement for the operation and functionality of the security wrap flexible circuit. The conductive ink can also be carbon, graphite, clear conductive polymer or other conductive or resistive ink, each with specific properties that suit the necessary requirement for the operation and functionality of the security wrap.
A dielectric layer such as a UV curable ink system with electrically insulative properties may be used to electrically insulate the security screen 22 to avoid short circuits, if needed.
The adhesive layer 54 is preferably a pressure-sensitive adhesive (PSA), typically an acrylic adhesive that forms a bond between surfaces when pressure is applied. The adhesive may be applied as an adhesive ink or as a laminate. The adhesive layer is used to bond the security wrap to the parent device. Alternatively, the adhesive maybe a liquid adhesive such as an epoxy, or moisture-cure urethane etc. which is dispensed or printed between the security wrap and the PCB, which is then cured by moisture, thermal or UV energy and forms a permanent bond between wrap and PCB. This type of adhesive is not pressure sensitive, but could work under the same disclosed principle.
Depending on the material of the parent device 10 to which the security wrap 20 is adhered a variant PSA with specific adhesion properties could be used. Specifically the adhesion to the parent device 10 must be stronger than the adhesion to the substrate 50 , so that on removal of the security wrap 20 from the parent device 10 , the adhesive layer 54 will remain adhered to the parent device 10 in order to break the conductor of the conductive circuit 22 .
First wrap 20 differs from the second wrap 30 in that normally the screen terminals are on the same side of the substrate 50 as the screen and the adhesive so that the security wrap protects the connections to the alarm terminals. However, as the screen of the first wrap 20 needs to be connected to the screen of the second wrap 30 , the first screen terminals 24 extend through the first substrate 50 as shown in FIG. 6 . This is preferably achieved by a printed or filled through hole, although a plated through hole could be used. A printed through hole is formed by making a suitable hole in the substrate 50 and filling it with conductive ink, typically at the time of forming the conductors of the screen, thus providing a conductive path through the substrate 50 . Such holes are known as a via. The connection is protected by the second wrap 30 .
The screen terminal 34 of the second wrap 30 is formed as a projection of the end of the conductor 32 forming the second screen and preferably forms a projection extending into the adhesive layer 54 . The actual connection between the first and second screens 20 , 30 may take different forms.
FIG. 6 illustrates the preferred method using conductive domes 56 . The dome 56 is inserted into a recess 58 in the adhesive layer 54 aligned with the corresponding second screen terminal 34 such that the dome 56 is in electrical contact with the second screen terminal 34 of the second wrap 30 and is aligned with the corresponding first screen terminal 24 of the first wrap 20 . The dome 56 can be arranged in two ways. Firstly as a resilient contact whereby the adhesive provides a mild compression force on the dome 56 so that the resilience of the dome 56 allows the connection to tolerate slight movement as may occur for example by rough handling or thermal expansion of the various components. Alternatively, the dome 56 acts a spring loaded lift off contact requiring an external force to be applied to the connection in order to compress the dome to establish an electrical connection between the screen terminals. The dome 56 is shown in the relaxed state in FIG. 6 .
FIG. 5 is an exploded schematic illustrating a preferred method of applying force to the connections. The dome 56 , in the relaxed state, lifts of the screen terminal 24 breaking electrical contact there with. Spigots 19 formed on a part of the housing for the PCB 12 are arranged to bear down on the second security wrap 30 so as to press the second screen terminals 34 against the domes 56 and the domes 54 against the first screen terminals 24 to establish an electrical connection between the screens as the housing is closed. When the housing is opened, the spigots 19 separate from the security wrap 30 and the dome 56 relaxes breaking the connection and raising an alarm condition. In this way, an alarm condition is triggered by merely opening the housing before any direct attempt to remove the security wrap 30 is made.
FIG. 7 is an enlarged sectional view, similar to FIG. 6 , of a different method of connecting the screens. The dome is replaced by a carbon pad 60 which is slightly thinner than the adhesive layer 54 so that the carbon pad 60 faces the first screen terminal 24 across a small air gap 62 . The carbon pad 60 makes direct contact with the second screen terminal 34 and may actually form the second screen terminal 34 . When an external force is applied to the second wrap 30 in the region of the carbon pad 60 , the second substrate 50 is resiliently deformed and the carbon pad 60 is pressed against the corresponding first screen terminal 24 , establishing an electrical connection between the screens. On removal of the external force, the substrate 50 relaxes and the carbon pad 60 separates from the first screen terminal 24 to break the connection thus raising an alarm condition.
FIG. 8 illustrates another connection method wherein a plug 64 of conductive material replaces the carbon pad 60 shown in FIG. 7 . The plug 64 completely extends across the thickness of the adhesive layer 54 to make direct contact between the first and second screen terminals 24 , 34 . The plug 64 may be of any suitable material such as conductive foam but preferably it is formed of conductive ink, formed at the time of printing the conductors of the second screen. The plug 64 maybe directly connected to the first screen terminal 24 by pressure from the adhesive layer, or by conductive adhesive, conductive paste, etc.
While the preferred embodiment uses security wraps with breakable conductors the present invention is also applicable to more traditional security wraps where the conductors of the security screen as not specifically designed to be broken if the security wrap is removed from the device. Depending on the complexity of the alarm circuit, a security screen may have any number of conductors.
While the drawings have been enlarged for better clarity of observation and description, in the preferred embodiments, the width of the conductive traces and the spaces there between are in the range of 1 to 1,000 microns. The preferred embodiment uses a trace width between 200 and 300 microns. This produces a good compromise between costs and security level as the finer the widths the higher the security level but the printing process is more expensive.
In the description and claims of the present application, each of the verbs “comprise”, “include”, “contain” and “have”, and variations thereof, are used in an inclusive sense, to specify the presence of the stated item but not to exclude the presence of additional items.
Although the invention is described with reference to one or more preferred embodiments, it should be appreciated by those skilled in the art that various modifications are possible. Therefore, the scope of the invention is to be determined by reference to the claims that follow. | The present invention provides a security assembly for protecting a device includes first and second security wraps fitted to the device. The first security wrap covers a first area of the device. The second security wrap partially overlaps the first security wrap and covers a second area of the device. Each of the first and second security wraps has a security screen having first and second screen terminals and a conductive track extending between the first and second screen terminals. A conductive structure is disposed in an overlapping area between the first and second security wraps and coupled to the second screen terminal of the first security screen and to the first screen terminal of the second security screen. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a retainer package for surgical sutures, and, more particularly, to a molded retainer incorporating a novel needle park for securely retaining one or more surgical needles.
2. Description of the Prior Art
Many types of retainers for surgical sutures and suture-needle assemblies are well known in the art. Generally, a retainer should be constructed to adequately secure a needle and suture while providing easy withdrawal during use. It is also preferable to minimize the formation of kinks or bends in the suture during storage.
A first type of known retainer consists of a series of panels interconnected to each other along score lines. The panels are adapted to fold onto each other to enclose a suture packaged therein. Typically, the suture is wound in an oval or figure "8" pattern within the retainer. The needle may be secured in a slot or die cut formed in one of the panel members, or in the alternative, may piercingly engage a foam strip affixed to a panel member.
Another type of retainer is of molded construction such as the retainer disclosed in U.S. Pat. No. 5,154,283 to Brown. The retainer described in the Brown '283 patent includes a molded cover member having a spiraled passageway formed therein to accommodate a suture and a cover sheet adhered to the molded member to close the passageway. The passageway is characterized by defining a relatively wide channel having a width several times the diameter of the suture disposed therein. A significant feature of this package is that the sutures stored therein exhibit fewer kinks and bends as compared to prior suture packages.
Although the Brown '283 patent has proved to be extremely effective in storing sutures and minimizing the formation of kinks or bends in the suture during storage, the present invention relates to further improvements whereby a molded retainer incorporates a novel needle park to retain the needle in an effective and secure manner while providing easy withdrawal during use.
SUMMARY OF THE INVENTION
A suture retainer comprises a molded base panel having a passageway formed therein for reception of a suture portion, a cover sheet affixed to the molded base panel to enclose the passageway and needle holding means extending generally transversely relative to a plane defined by the base panel through an opening formed in the cover sheet for securably engaging a needle attached to the suture portion.
The needle holding means comprises a needle park integrally formed with the molded base panel and defining a needle receiving channel dimensioned to receive and accommodate the needle therein. The needle receiving channel is configured in a manner such that portions of the needle park defining the needle receiving channel frictionally engage the outer surfaces of the needle to secure the needle to the needle park.
In an alternative preferred embodiment, the molded needle park comprises at least two projecting members extending generally transversely relative to a plane defined by the molded base panel. The projecting members define the needle receiving channel therebetween and may be positioned to frictionally engage the needle received within the needle receiving channel. Each projecting member has a lip portion formed contiguous therewith. The lip portions extend generally inwardly towards the center of the needle receiving channel and are particularly oriented to engage the needle to retain the needle within the receiving channel.
The molded base panel of the preferred retainer comprises a moldable transparent plastic material while the cover sheet is constructed of a spun bonded polyolefin. The cover sheet includes a suture receiving port to permit access to a suture receiving section of the passageway of the base panel and a vacuum port aligned with a vacuum receiving section of the passageway. The suture retainer may also comprise a needle cover panel foldably attached to the cover sheet and adapted to fold onto the needle within the needle holding means.
The present invention is also directed to a suture retainer for storing at least one suture having a needle attached thereto, comprising a molded base panel having a passageway formed therein for accommodating a suture portion, a cover sheet affixed to the molded base panel to enclose the passageway and at least one needle holding park integrally formed with the molded base panel and extending through at least one opening formed in the cover sheet. The needle park defines a groove therein dimensioned and configured to receive a suture needle and frictionally engage the outer surfaces of the needle to secure the needle to the retainer.
The present invention is further directed to a needle park for retaining at least one surgical needle in a suture retainer. The needle park comprises a base panel having two projecting members extending generally transversely relative to a plane defined by the base panel and defining a needle receiving channel therebetween for accommodating a needle. The projecting members each have a lip portion formed contiguous therewith which extend generally inwardly towards the center of the receiving channel. The lip portions are oriented in a manner to at least partially enclose the channel and retain the needle against the base panel.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, referred to herein and constituting a part hereof, illustrate the preferred embodiments of the present invention, and together with the description serve to explain the principles of the invention, wherein:
FIG. 1 is a perspective view of a preferred embodiment of a suture retainer constructed in accordance with the present invention;
FIG. 2 is a perspective view with parts separated of the suture retainer of FIG. 1 illustrating the base panel with the needle park integrally formed therewith, a suture in a coiled configuration and the cover sheet;
FIG. 3 is a cross-sectional view taken along the lines 3--3 of FIG. 1 illustrating securement of the needle in the needle park;
FIG. 4 is a view similar to the cross-sectional view of FIG. 3 illustrating an alternative needle park having a generally arcuate channel portion for accommodating the needle;
FIG. 5 is a perspective view of the suture retainer of FIG. 1 with two needle parks;
FIG. 6 is a partial perspective view of an alternative needle park to be incorporated in the suture retainer of FIG. 1, including transverse retaining members having generally inwardly extending lip portions to engage the needle;
FIG. 7 is a partial perspective view of another alternative needle park, including a molded raised portion having a needle receiving slot therein for retaining the needle;
FIG. 8 is a cross-sectional view taken along the lines 8--8 of FIG. 7;
FIG. 9 is a cross-sectional view taken along the lines 9--9 of FIG. 7;
FIG. 10 is a view similar to the cross-sectional view of FIG. 8 illustrating an alternative embodiment of the needle park of FIGS. 7-9, including an arcuate slot portion for accommodating the needle; and
FIG. 11 is a partial perspective view of another alternative embodiment of a needle park, including a molded raised portion having two apertures formed in opposed walls for reception of the needle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIG. 1, there is illustrated in perspective view the suture retainer 20 constructed according to the present invention. Retainer 20 is similar to the retainer disclosed in U.S. Pat. No. 5,154,283 to Brown, the contents of which are incorporated herein by reference. Retainer 20 is particularly adapted to accommodate a double or triple folded suture in a suture compartment defined by the retainer, and to retain a needle attached to the suture in a readily accessible position adjacent the retainer.
Referring now to FIGS. 1-3, retainer 20 includes base panel 22 having passageway 24 formed therein for accommodating suture A in a coiled configuration and a cover sheet 26 for enclosing the passageway. Passageway 24 is characterized in that it possesses a minimal number of convolutions. The passageway 24 follows a generally oval pattern commencing at peripheral suture receiving section 28 and spiraling toward the proximate center through several turns while terminating at a central vacuum receiving section 30.
Base panel 22 is fabricated from a moldable transparent plastic material such as, for example, polyethylene terapthalate (PETG), of Eastman Kodak 6763. Other materials suitable for base panel 22 include polyvinylchloride, polyethylene, polypropylene and high impact polystyrene. Base panel 22 is approximately 3.350 inches (85.09 millimeters) by 1.375 inches (34.925 millimeters) in order to conform to commonly accepted overall dimensions of conventional suture packages and display boxes. The retainers are preferably about 0,010 inches (0.254 millimeters) thick.
A needle park identified by reference numeral 32 extends generally transversely from base panel 22 along the general midline M of the panel 22 (FIG. 1). As best depicted in FIG. 3, needle park 32 includes two transverse members 34 which define a needle receiving channel 36 therebetween. Needle channel 36 is strategically dimensioned to receive and accommodate a needle B therein, and to securely retain the needle B against cover sheet 26 in the manner shown in FIG. 1. In a preferred embodiment, transverse members 34 are positioned to frictionally engage portions of the inner and outer surfaces of needle B as shown in FIG. 3. Transverse portions 34 may also be slightly resilient and capable of deforming to the outer contours of needle B. In an alternative embodiment shown in FIG. 4, needle receiving channel 36 may possess a lower base portion 38 of generally arcuate cross-section to accommodate needle B. Base portion 38 of channel 36 is preferably dimensioned to generally correspond to the outer dimension or contours of needle B such that the needle park material surrounding the base portion substantially encloses the needle B within the needle park.
Referring again to FIGS. 1-3, needle park 32 extends through a circular opening 40 defined in cover sheet 26. Accordingly, in the secured position of needle B, the needle is retained in a prostrate position against cover sheet 26 in general parallel relationship with base panel 22. Such parallel positioning of needle B minimizes the overall girth of retainer 20 thereby facilitating packaging of the retainer within an outer package.
Needle receiving channel 36 defined by transverse members 34 may be substantially straight to facilitate retention of a straight surgical needle. In the alternative, needle receiving channel 36 may be slightly curved to facilitate retention of a curved surgical needle. In the preferred embodiment, needle park 36 is integrally formed with base panel 22. However, it is also within the scope of the present invention for needle park 32 to be an independent component separate from base panel 22. It is also contemplated that retainer 20 may contain several needle parks 32 to accommodate a plurality of surgical needles as shown in FIG. 5 where two needle parks 32 are provided so as to secure the needles of a double armed suture.
Referring now to FIGS. 1 and 2, cover sheet 26 is configured and dimensioned to overlie base panel 22 and is adhesively attached to the base panel 22 along respective peripheral portions thereof to enclose the passageway 24. In a preferred embodiment, cover sheet 26 is adhered to base panel 22 with a hot melt adhesive from Oliver Products of Minneapolis, Minn.
The cover sheet 26 is provided with a vacuum aperture 42 and a suture entrance aperture 44. Vacuum aperture 42 aligns and communicates with the central vacuum receiving section 30 of the molded base panel 22. Similarly, suture entrance aperture 44 aligns and communicates with the suture receiving section 28. Preferably, cover sheet 26 is constructed of a material which is pervious to ethylene oxide sterilizing gas. The preferred material is a spun bonded polyolefin, such as TYVEK™ 1073B available from E.P. DuPont de Nemours & Co.
Referring still to FIGS. 1 and 2, a preferred cover sheet 26 includes a needle cover panel 46 joined to the main section of the cover sheet along doubled perforated score line 48 and openings 50. Needle cover panel 46 is adapted to fold onto needle B retained within the needle park 32 to protect the needle when the retainer is in a secured position.
Suture A may be loaded into retainer 20 by initially folding the suture onto itself to form a first loop and then folding the suture again onto itself to form a second loop. The number of loops required generally depends on the length of the suture to be loaded. Thereafter, the suture portions opposite needle B are inserted through suture entrance aperture 44 in cover sheet 26 and into suture receiving section 28 of base panel 22. A vacuum is applied to the retainer by, e.g., placing a vacuum block (not shown) over vacuum aperture 42 to draw suture A into passageway 24 of base panel 22. The vacuum is applied until needle B is disposed substantially adjacent suture entrance aperture 44. Thereafter, needle B is positioned within needle receiving channel 36 of needle park 32. As an alternative insertion technique, needle B may be positioned within needle park prior to loading suture A. Thereafter, a vacuum may be applied to vacuum aperture 42 to draw the suture A into the retainer.
Retainer 20 with loaded suture A and needle B may be packaged within an outer package. In the case of nonabsorbable sutures, the suture and retainer may be enclosed in a so-called breather pouch suitable for gas sterilization, such as a pouch consisting on one side a sheet of polyolefin (TYVEK™) and on the other side a clear plastic sheet such as polyethylene. The breather pouch is opened by peeling the two sides of the breather pouch apart and opening the needle cover panel to reveal the needle which may be readily grasped to remove the suture from the retainer by a pulling motion.
With synthetic absorbable sutures, the retainer may be packaged in a foil laminate inner envelope which would be further packaged within an outer breather pouch. A preferred inner envelope is disclosed in U.S. patent application Ser. No. 07/718,198, filed Jun. 20, 1991, the contents of which are incorporated herein by reference and includes a top layer having first and second top panels adhered to each other transversely and defining a gripping tab. The top panels are adhered to a bottom panel along respective peripheries thereof to define a pocket for receiving the retainer.
The foregoing inner pouch is preferred, but it will be understood that other types of envelopes such as conventional tearable foil laminate envelopes may be used. It is contemplated that the suture could be sterilized by ethylene oxide permeating through an opening in the pouch which is subsequently sealed and that the peelable pouch itself could be sterilized and maintained sterile in an outer breather pouch in a known matter.
Referring now to FIG. 6, there is illustrated a partial perspective view of an alternative embodiment of a needle park to be incorporated in retainer 20 of the present invention. Needle park 60 includes two projecting members 62a, 62b extending generally transversely from base panel 22 and through opening 40 defined in cover sheet 26. Projecting members 62a, 62b define a needle receiving channel 64 therebetween to accommodate and retain needle B in a manner similar to the needle park 32 described in connection with the embodiment of FIG. 1. In particular, projecting members 62a, 62b may be dimensioned and positioned to frictionally engage the outer surfaces of needle B. In the alternative, projecting members 62a, 62b may be positioned to define a needle receiving channel 64 of greater dimension so as to permit slight movement of the secured needle B.
Projecting members 62a, 62b also include generally inwardly extending lip portions 66a, 66b formed contiguous with their respective projecting members. Lip portions 66a, 66b are strategically oriented, preferably, in parallel relation to base panel 22 so as to engage needle B to further facilitate retention of the needle within needle park 60 and against cover sheet 26. In particular, lip portions 66a, 66b restrict movement of needle B away from the retainer thereby securing the needle B against the cover sheet. Thus, the combination of transverse members 62a, 62b and lip portions 66a, 66b securely retain the needle within retainer 20.
Referring now to FIGS. 7-9, there is illustrated another embodiment of a needle park which may be incorporated in the retainer of the present invention. Needle park 70 is preferably integrally formed with a molded substantially planar base panel 72 by, e.g., vacuum molding techniques, to form a hollow raised surface portion 74. Raised surface portion 74 includes a needle receiving slot 76 (FIG. 8) for receiving surgical needle B. Slot 76 can be constructed to have weakened portions 75 to facilitate securement of needle B by means of deformation. Needle B is positioned within slot 76 wherein portions 75 slightly deflect to accommodate the needle. Due to the hollow configuration of the raised surface portion 74, needle B is engaged by contacting portions 78, 80 of the raised surface as shown in the cross-sectional view of FIG. 9. Contacting portions 78, 80 frictionally engage the outer surfaces of needle B to secure the needle within park 70. Needle receiving slot 76 may be substantially straight to receive a straight needle B, or, in the alternative, be slightly arcuately shaped or curved to receive a curved needle B. Needle park 70 may also be provided with a needle receiving slot 76 having an arcuate lower base portion 82 as shown in FIG. 10. In accordance with the embodiment of FIG. 10, the arcuate base portion 82 of needle receiving slot 76 is preferably dimensioned to generally correspond to the outer contour of needle B to substantially surround a peripheral portion of the needle B.
Referring now to FIG. 11, there is illustrated in partial perspective view another embodiment of a needle park of the present invention. This embodiment is substantially similar to the embodiment described in connection with FIG. 10, except that the needle receiving slot 76 has been replaced with two arcuate apertures 84,86 formed on opposed sides of the raised portion. Arcuate apertures 84,86 receive needle B therein. In particular, during securing of needle B within the park, the pointed end of needle B is inserted within aperture 84, passed through the raised portion and out aperture 86 on the opposed side of the raised portion. Preferably, the dimensions of apertures generally correspond to the outer peripheral surface of needle B, and, are preferably dimensioned to frictionally engage the needle. The apertures 84,86 may be in direct alignment with each other to secure a straight surgical needle or, in the alternative, may be slightly offset to accommodate the arcuate configuration of a curved surgical needle B.
The invention in its broader aspects therefore is not limited to the specific embodiments herein shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principals of the invention and without sacrificing its chief advantages. | A suture retainer for storing at least one suture having a needle attached thereto comprises a molded base panel having a passageway formed therein for accommodating a suture portion, a cover sheet affixed to the molded base panel to enclose the passageway and at least one needle holding park integrally formed with the molded base panel and extending through at least one opening formed in the cover sheet. The needle holding park defines a groove dimensioned and configured to receive a suture needle and frictionally engage the outer surfaces of the needle to secure the needle to the retainer. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a test system for a random access memory (RAM). The system according to the present invention is concerned with a RAM testing system which is provided with latch units at both the input side and the output side of the RAM. A measurement of the address access time by the widths of clock pulses can be carried out with a high precision.
2. Description of the Related Art
In general, in the prior art method of testing the access time of RAM's, signals are delivered to address input pins of a RAM from drivers of an LSI tester and the outputs of the RAM are fed to a comparator, thus implementing the measurement of the address access time. In this case the address inputs of the RAM are equivalent to a clock input of the latch when an input latch is provided.
In the conventional RAM testing system, the output of an oscillator is fed to each delay circuit and set signals are also delivered to the delay circuits to generate a clock signal No. 1, and a clock signal No. 2. The clock signal No. 1, is fed to input side flip-flop circuits and address signals are fed to the flip-flop circuits to send the output of the flip-flop circuits to the RAM elements to be tested. On the other hand, the clock signal No. 2 is fed to the output side flip-flop circuits. Each output of the output side flip-flop circuits is fed to comparators to which the expectation value is applied, respectively, and the outputs of the comparators are sent to a discriminator.
In the device of FIG. 1, two clock signals having different delay times are supplied to the input side flip-flop circuit and to the output side flip-flop circuit through the terminal pin PIN-A and through the terminal pin PIN-B, respectively.
Therefore, a problem arises in that an error occurs due to the difference in the timing of the signals through different terminal pins of the LSI tester, and an address access time of a RAM responsive to the clock pulse can not be accurately measured.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved test system for a RAM for measuring the address access time of a RAM with a high precision.
Accordingly, in accordance with the present invention, there is provided a test system for a random access memory including: clock pulse width varying means for varying a pulse width of driving pulses for a random access memory; a first latch means connected to an address input circuit of the random access memory for receiving the output clock signal of the clock pulse width varying means and latching an address input signal at the leading edge of the output clock signal; a second latch means connected to a data output circuit of the random access memory for latching a data output signal, both the first and second latch means being supplied with the same clock signals from the clock pulse width varying means; and comparison means connected to a data output circuit of the random access memory for comparing the output of the random access memory with a predetermined expectation value corresponding to address access time of the random access memory; the output of the comparison means being latched by the trailing edge of the clock pulse in the second latch means.
The present invention utilizes only one channel and uses the access time between the input and output latches of a RAM to be tested, thus remarkably reducing the skew.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a prior art RAM tester;
FIG. 2 is a block diagram of a test system for RAM in accordance with an embodiment of the present invention;
FIG. 3 is a block diagram of the structure of a clock pulse width varying portion in the system of FIG. 2;
FIG. 4 is a waveform diagram showing the signals appearing in the portions of the system of FIG. 2;
FIG. 5 is a waveform diagram showing the signals appearing in the principal parts in the system of FIG. 2;
FIG. 6 is a block diagram of the structure of a comparator portion and an output latch portion in FIG. 2 of the present invention; and
FIG. 7 is a block diagram of the waveforms at the output parts of the comparator portion and at the points A, B, . . . E, and F of the output latch portion.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before describing the preferred embodiments of the present invention, a prior art test system for RAMs is described with reference to FIG. 1.
In FIG. 1, the output of an oscillator is fed to each delay circuit and set signals are delivered to the delay circuits to generate a clock signal No. 1, and a clock signal No. 2. The clock signal No. 1 is fed to the input side flip-flop circuits and address signals are fed to the flip-flop circuits to send the output of the flip-flop circuits to memory elements to be tested. On the other hand, the clock signal No. 2 is fed to the output side flip-flop circuits. Each output of the output side flip-flop circuits is fed to each of the comparators to which the expectation value is applied, respectively, and the outputs of the comparators are sent to a discriminator.
In the system of FIG. 1, two clock signals having different delay times are supplied to the input side flip-flop circuit and to the output side flip-flop circuit through the terminal pin PIN-A and through the terminal pin PIN-B, respectively.
A test system for a RAM according to an embodiment of the present invention will now be described with reference to FIG. 2.
In FIG. 2, a clock pulse is sent to a clock pulse width varying portion 2, where a delay control signal is delivered to vary the width of the clock pulse. The output of the clock pulse width varying portion 2 is sent to an address latch 4 and an output latch 6 simultaneously. The address latch 4 samples new address signals by a leading edge of the clock pulse and the output latch 6 is latched by a trailing edge of the clock pulse (Sample is carried out also from the leading edge timing), thus comparing the output of the RAM 1 with the output expectation value responsive to the address access time of the RAM 1 by a comparator 5 or exclusive OR circuit. The exclusive-OR gate will provide an output (logic 1) only when the two inputs are not alike. This means that the two inputs must have a different logic level in order for a logic 1 output to occur. Note that for the exclusive-OR gate, an output (logic 1) results only in steps when two inputs are "0", "1" or "1", " 0", i.e., where the inputs have a different logic state.
The exclusive OR gate is used in binary word detection. For example, when two input words are identical, the output is low. If the words are not identical, the output is high. This type of word comparison is very helpful when searching through a large amount of data or words for a particular word. The number of times the word occurs can be counted with this circuit, by providing a frequency count of the word. The address access time of the RAM can be measured with high precision by the comparator output. Moreover, the pulse width of the clock pulse can be counted by measuring the clock frequency by a frequency counter.
By using a detailed circuit diagram of the important parts of FIG. 2, the embodiment of the present invention will be described in detail with reference to FIG. 3.
FIG. 3 is a detailed circuit diagram of a clock pulse width varying portion 2 in FIG. 2. The clock pulse width varying portion is composed of a variable delay circuit by twenty-five stages of ring oscillators and a chopper circuit formed which determines the pulse width in response to the delay time. Based on such a constitution, the frequency of the output clock is measured to determine its pulse width with a high accuracy.
A clock from an LSI tester is input to a terminal 201, and a ring oscillator enable signal is input to a terminal 203. The clock pulse, which is controlled to a predetermined pulse width, is output from a terminal 204 and sent to an address latch 4 and an output latch 6 (FIG. 2). A delay time control signal generator 21 generates a delay time control signal and sends it to a decoder 22, and then after a decoding operation, the output of the decoder 22 is sent to five NOR circuits No. 17, 19, 21, 23 and 25.
Each numeral of the NOR circuits DLY (1) to DLY (25) represents a relative amount of delay of a clock signal. Therefore, when the ring oscillator enable signal at a terminal 203 is LOW and a signal is sent which selects a path 221 by a decoder 22, the delay time T d25 of the twenty five stages of ring oscillator can be measured at a frequency counter (not shown) which is connected to the output of the OR circuit 23. As a result, when the data paths 221 to 225 are selected respectively, the chopped pulse width t WC can be calculated. For example, in the case of the data path 221,
t.sub.WC =T.sub.d25 ×(17/25)=T.sub.p1
The same holds true for the paths 222 to 225,
T.sub.p2 =T.sub.d25 ×(19/25)
T.sub.p3 =T.sub.d25 ×(21/25)
T.sub.p4 =T.sub.d25 ×(23/25)
T.sub.p5 =T.sub.d25
The operating test of a RAM is carried out so that the standard value T AACK for checking an address access time T AA of a RAM 1 may be previously determined and the data path having the condition
T.sub.p(n-1) <T.sub.AACK <T.sub.pn
may be utilized.
Therefore, irrespective of the precision of the clock pulse width given by an LSI tester, a clock having a pulse width with a good precision can be output by a clock pulse width varying portion 2 (FIG. 2). That is, in response to the pulse width of a clock pulse output from the clock pulse width varying portion 2, the address access time T AA of the RAM 1 can be precisely measured.
FIG. 4 is a waveform diagram of each portion in FIG. 2. In FIG. 5, item (1) denotes an address signal S (3) in FIG. 2, item (2) a RAM output S (1), item (3) an expectation value S (EXPECT), item (4) a comparator output S (5), item (5) a clock, and item (6) a resulting output S (6), respectively.
First, address data is applied to an address latch 4 to produce an address signal. The address signal is applied to a RAM 1 to output the data. The waveform of an old address is changed to that of a new address, and accordingly, the RAM output is changed from "1" to "0". In the region of a minimum time to a maximum time, the level of RAM output is not fixed. Correspondingly, the output expectation value is also changed from an old value to a new value. The changing point of the expectation value is a little earlier than the changing point of the address signal. In response to the changing point of the output expectation value, the output of a comparator circuit varies from a coincident region to a non-coincident region and returns to the coincident region.
When a common clock pulse is supplied to the address latch 4 and the output latch 6, the address latch 4 samples a new address signal by a leading edge of the clock pulse, and the output latch 6 is devised to close the latch by a trailing edge of the clock pulse, thus comparing the RAM output with the output expectation value responding to the address access time of the RAM. For example, when the latch output at the output side is changed from "1" to "0", if the latch is closed, and if the latch is definite, the "0" output is produced. As a result, the address access time of the RAM can be measured with a high accuracy.
After the output of the RAM 1 and the output expectation value are compared, the result of the comparison is latched by the trailing edge of the clock pulse at the output latch 6. If the clock coincides with the resultant output of the latch, the output is "0".
The cells within the RAM 1 are selected by the address output of the address latch 4 and the output responsive thereto is fetched from the RAM 1. For a period, the output and the output expectation value are compared by the NOR circuits 51, 52, 53 (FIG. 6). During that time, the NOR circuits 62, 63 are left open, the output latch portion 6 is closed by a trailing end of the clock pulse, and it is determined whether or not the output of the RAM has reached the value of the output expectation value. By varying the pulse width of the clock pulse, the time period from the opening time to the closing time of the address latch 4 and the output latch 6, that is, the time duration response to the pulse width of the clock pulse, enables the address access time of the RAM to be measured.
FIG. 5 is a waveform diagram showing the signals appearing in the principal parts in the device of FIG. 2. In FIG. 5, item (1) denotes a cycle period, item (2) a clock, item (3) a latch input S (3) in FIG. 2, item (4) a latch output S (4), item (5) a RAM output S (1), item (6) an expectation value S (EXPECT), item (7) a comparator output S (5), item (8) a resulting output S (6), and item (9) a tester strobing pulse, respectively.
In each cycle period, a clock is generated. Responding to the latch input S (3) and the latch output S (4), the RAM output S (1) is generated, but the level of RAM output is not fixed from the minimum time length to the maximum time length. When the expectation value changes from "1" to "0", the comparator output is generated, and responding to the open and close state of a clock, the resulting output S (6) is obtained.
FIG. 6 is a detailed connection diagram of a comparator portion and an output latch portion of FIG. 2 of the present invention. In an embodiment of FIG. 6, the output of RAM 1 is of 4 bits, which possess a plurality of complementary outputs (+Q, -Q). The RAM has generally only either output (as an example, +Q), and has a complementary output (in this case, -Q), within the RAM.
In FIG. 2, the output terminal of clock pulse width varying portion 2 is connected to an address latch 4 and output latch 6. The output of the address latch 4 is connected to an address input (AD) of the RAM 1. The outputs of the address accessed RAM 1 are obtained respectively as each set of complementary outputs (+Q 0 to +Q 3 , (-Q 0 ) to (-- 3 )), and after a wired OR operation, are connected to the first input of the NOR circuits 52 and 53.
The comparator portion 5 is composed of eight emitter follower type transistors 501-508 and three NOR circuits 51, 52 and 53. The eight outputs of the RAM 1 are divided into true side wires OR outputs (+Q 0 , +Q 1 , +Q 2 , and +Q 3 ) and inversion side wired OR outputs (-Q 0 , -Q 1 , -Q 2 , and -Q 3 ) to send each first input to the NOR circuits 52 and 53.
The output expectation value is input to a NOR circuit 51, the non-inverted output is sent to a second input terminal of the NOR circuit 52, and the inverted output is sent to a second input terminal of the NOR circuit 53, respectively. The non-inverted output of the NOR circuit 61 is connected to each third input of the NOR circuits 52 and 53, and the inverted output is connected to the first input of the NOR circuit 62. The outputs of the NOR circuits 52, 53 and 62 are respectively connected to the first, second and third input terminals of a NOR circuit 63. The output of the NOR circuit 63 is connected to the second input of the NOR circuit 62 and, at the same time, acts as a resulting output of the output latch portion 6.
FIG. 7 is a waveform diagram of each portion of FIG. 6. After four true side wires OR's (+Q 0 , +Q 1 , +Q 2 and +Q 3 ) are connected to the NOR circuit 52, the first input A is changed from "1" to "0" and the second input B is constantly equal to "0". The output of the NOR circuit 52 is shown by a waveform C and the resultant output is shown by a waveform output. The non-inverted output of the NOR circuit 61 is shown by the waveform D and the inverted output by the waveform E. The output of the NOR circuit 62 (waveform F) shows the variation from a LOW level to a HIGH level and the latch is closed. | A test system for a random access memory includes a clock pulse width varying unit for varying a pulse width of driving pulses for a random access memory. A first latch is connected to an address input circuit of the random access memory for receiving the output clock signal of the clock pulse width varying unit and latching an address input signal at the leading edge of the output clock signal. A second latch is connected to a data output circuit of the random access memory for latching a data output signal. Both the first and second latches are supplied with the same clock signals from the clock pulse width changing unit, and a comparison unit is connected to a data output circuit of the random access memory for comparing the output of the random access memory with a predetermined expectation value. The output of the comparison unit is latched by the trailing edge of the clock pulse in the second latch. | 6 |
BACKGROUND OF THE INVENTION
This invention relates generally to novel compounds which are useful as precursors in the preparation of catalysts which effect the metathesis of olefins, including functionalized olefins and to novel methods for their preparation. More specifically, novel compounds in accordance with embodiments of the present invention comprise transition metal based complexes which provide a facile chemical synthesis to producing corresponding transition metal based catalysts. Such complexes may be represented by the following structural formula I
M(R.sub.1).sub.2 (NR.sub.2).sub.2 (R.sub.3).sub.x (I)
in which M, R 1 , R 2 , R 3 , and x are defined below.
In addition, the present invention also encompasses within its scope novel methods for the production of these complexes. These methods are more advantageous than prior methods because they are more economical in both the reaction time and the cost of starting materials.
The metathesis process can be defined as the redistribution of alkylidene moieties in a mixture of olefins. The simplest example is
2R'CH═CHR⃡R'CH═CHR'+RCH═CHR
The reaction proceeds by addition of an olefin to a catalyst having a metal-carbon double bond (M═CHR, a metal-alkylidene complex) to give a metal-lacyclobutane ring, which then releases an olefin to reform a metal-alkylidene complex. A typical olefin of interest which will undergo metathesis in the presence of catalysts having a metal-carbon double bond is an ester of oleic acid, cis-CH 3 (CH 2 ) 7 CH═CH(CH 2 ) 7 CO 2 H. Three of the most active metals used in classical olefin metathesis are molybdenum, tungsten and rhenium. (Ivin, K.J., Olefin Metathesis, Academic Press, London, 1983; Grubbs, R.H. in Comprehensive Organometallic Chemistry, Wilkinson, G. et al. (Eds), Vol. 8, Pergamon New York (1982); Dragutan, V. et al., Olefin Metathesis and Rinq-Ooeninq Polymerization of Cyolo-Olefins, 2nd Ed., Wiley-Interscience: New York (1985); Leconte, M. et al. in Reactions of Coordinated Lioands, Braterman, P.R. (Ed.), Plenum: New York (1986).)
Examples of molybdenum (VI) alkylidene complexes (Murdzek, J.S. and R.R. Schrock, Organometallics 6: 1373 (1987); Bazan, G. et al., Polymer Commun. 30: 258 (1989); Schrock, R.R., Murdzek, J.S., Bazan, G.C., Robbins, J., DiMare, M., and O'Regan, M., Synthesis of Molybdenum Imido Alkylidene Complexes and Some Reactions Involving Acyclic Olefins, J. Am. Chem. Soc. Vol. 112, p. 3875-3886 (May 9, 1990)) and tungsten (VI) alkylidene complexes have been previously described (Schrock, R.R. et al. in Advances in Metal Carbene Chemistry (Schubert, U. (Ed.), Kluwer Academic Publishers, Boston: 1989, page 323; Schrock, R.R. et al., Macromolecules 20: 1169 (1987); Ginsburg, E.J. et al., J. Am. Chem Soc. 111: 7621 (1989); Swager, T.M. et al., J. Am. Chem Soc. 111: 4413 (1989)
Several of these compounds have been shown to catalyze the metathesis of olefins with an activity that can be controlled through the choice of the alkoxide ligand. For example, molybdenum and tungsten catalysts reported by Schrock, R.R. (U.S. Pat. Nos. 4,681,956 and 4,727,215) have been shown to homogeneously metathesize at least 250 equivalents of methyl oleate.
Several rhenium alkylidene complexes have also been reported (Edwards, D.S. et al., Organometallics 2: 1505 (1983); Edwards, D.S., "Synthesis and Reactivity of Rhenium (VII) Neopentylidene and Neopentylidyne Complexes", MIT Doctoral Thesis (1983); Horton, A.D. et al., Organometallics 6: 893 (1987); Horton, A.D. and R.R. Schrock, Polyhedron 7: 1841 (1988); Cai, S. et al., J. Am. Chem. Commun., 1489 (1988). In particular, the Edwards references describe three rhenium complexes represented by the formula Re(C-t-Bu)(CH-t-Bu)(R) 2 where R is a t-butoxide, trimethylsiloxide or neopentyl moiety.
The catalysts may be produced by conventional synthesis techniques as described above. A way to achieve a desirable synthesis, is to employ a precursor which itself is both economically and easily prepared. Economy in the production of a precursor is reflected in cost of its starting materials, ease of handling its starting materials, length of reaction time and number of steps required to produce the precursors.
The compounds in accordance with embodiments of the present invention comprise precursors to the synthesis of catalysts which effect the metathesis of olefins, including functionalized olefins. Therefore, a principal object of the present invention is to provide precursor compounds which may be easily synthesized using low cost materials in as few steps as possible, thus lowering the overall cost for the production of the corresponding catalyst.
BRIEF SUMMARY OF THE INVENTION
This invention relates to novel compounds useful as precursors in the preparation of catalysts and to novel methods for synthesizing such compounds. These compounds have the general formula:
M(R.sub.1).sub.2 (NR.sub.2).sub.2 (R.sub.3).sub.x (I)
wherein M is molybdenum or tungsten;
N is nitrogen;
R 1 is halogen or triflate;
R 2 is phenyl or substituted phenyl, typically mono or di- C 1 -C 6 alkyl substituted phenyl;
R 3 is Lewis base; and,
x is 0, 1 or 2.
Lewis base is herein defined as compounds which are capable of donating an electron pair. The symbols M, R 1 , N, R 2 , R 3 and x as used hereinafter in the specification and in the claims have the same meaning as defined.
In accordance with the present invention, compound I is prepared preferably in an inert, dry atmosphere by mixing molybdate or tungstate with aniline or substituted aniline, a deprotonating agent, which will deprotonate the aniline or substituted aniline, halogenating or triflating agent, a coordinating Lewis base and a suitable solvent to produce six-coordinate compounds. If a coordinating Lewis base is not employed, corresponding four-coordinate compounds are produced. While the mixture will react at room temperature, it is heated to drive the reaction to completion. The six-coordinate compounds may be recovered as solids from the reaction mixture by distillation techniques, while the corresponding four-coordinate compounds may either be retained in solution or isolated as solids.
The features and advantages of the present invention may be more clearly understood by considering the following description of preferred embodiments.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention relates to compounds which are represented by compound I.
Referring to I, preferred substituents are molybdenum and tungsten for M, chlorine and bromine for R 1 , phenyl, 2,6-diisopropylphenyl, 2,6-dimethylphenyl and ortho-t-butylphenyl for R 2 , tetrahydrofuran, 1,2-dimethoxyethane, pyridine, quinuclidine, or phosphines of the general formula, P(R) 3 and (R) 2 PCH 2 CH 2 P(R) 2 where R is alkyl or aryl and other Lewis bases capable of donating a lone pair of electrons for R 3 . The novel precursor compound I may be synthesized in accordance with methods of the present invention by a novel reaction as follows.
Molybdate or tunqstate, for example ammonium molybdate (NH 4 ) 2 Mo 2 O 7 , alkylammonium molybdate [Mo 8 O 26 ][CH 3 N(C 8 H 17 ) 3 ] 4 and [Mo 8 O 26 ][HN(C 12 H 25 ) 3 ] 4 or their equivalent is combined under an inert atmosphere with amine of the general formula NHXAr, where Ar is phenyl or substituted phenyl, e.g. mono or di C 1 -C 6 alkyl substituted phenyl, typically 1,2-diisopropylphenyl, 1,2-dimethylphenyl or ortho-tert-butylphenyl, and where X is hydrogen or trimethylsilyl as in (CH 3 ) 3 SiNHAr. A compound capable of deprotonating NHXAr, for example, triethylamine, pyridine, substituted pyridine or other equivalent nitrogen bases and halogenating or triflating agent for example, Me 3 SiCl, Me 3 SiBr, Me 3 SiSO 3 CF 3 or their equivalent are further added to the reaction mixture. A suitable solvent is employed which may or may not contain an equivalent amount of coordinating Lewis base, for example, 1,2-dimethoxyethane (DME), tetrahydrofuran (THF), pyridine, quinuclidine, (R) 2 PCH 2 CH 2 P(R) 2 , and P(R) 3 where R =alkyl, aryl followed by heating to approximately 60°-70° C. for a minimum of 6 hours under an inert atmosphere, for example, nitrogen, yielding Mo(NAr) 2 (halogen) 2 (Lewis base) x where x is 0, 1 or 2.
The reaction product may be retained in solution or isolated as a solid by the evaporation of volatiles from solution using distillation techniques.
Four coordinate compounds of the present invention may be prepared, by employing non-coordinating solvents, such as toluene, diethylether, dichloromethane or trichloromethane, in the absence of coordinating Lewis bases. Compounds in accordance with embodiments of the present invention may then be used as novel precursors in the preparation of the corresponding catalysts by a three step reaction as follows.
Treatment of the compound with two equivalents of neopentyl or neophyl magnesium chloride leads to the production of an intermediate, having the general formula M(NAr) 2 (CH 2 R) 2 , where M, N and Ar have been previously defined and R=C(CH 3 ) 3 , CPh(CH 3 ) 2 where Ph =phenyl. Next, this complex is treated with three equivalents of a strong acid, such as triflic acid (HOSO 2 CF 3 ), in 1,2-dimethoxyethane (DME), generating a six coordinate complex, M(NAr)(CHR)(OSO 2 CF 3 ) 2 (DME). Two equivalents of lithium or potassium alkoxide is reacted with this complex yielding the catalyst M(NAr)(CHR)(R') 2 where R'=lithium or potassium alkoxide.
While the examples below relate to methods of preparation of novel precursor compounds containing molybdenum in accordance with embodiments of the present invention, it is to be understood that corresponding tungsten complexes can also be prepared using the methods of the present invention and employed in the same manner.
In order to further illustrate the practice of this invention, the following examples are included.
PREPARATION OF THE COMPOUNDS OF FORMULA I
EXAMPLE I
In an inert atmosphere, i.e. under a blanket of nitrogen, 10.00 grams (29.4 mmol) of ammonium molybdate,(NH 4 ) 2 Mo 2 O 7 , were suspended in 1,2-dimethoxyethane (DME) (150 mL) at room temperature. A solution of 23.80 grams of triethylamine (235.2 mmol) in 10 mL of DME was slowly added while stirring over a period of five minutes. There was no visible change in the solution. A solution of 54.20 grams of chlorotrimethylsilane (500 mmol) in DME (20 mL) was then slowly added while stirring over a period of five minutes. The solution became white and opaque. Finally, a solution of 20.80 grams of 2,6-diisopropylaniline (118 mmol) in DME (15 mL) was added while stirring over a period of five minutes. The solution turned yellow. Additional white precipitate formed as the reaction progressed. The mixture was then heated to 70° C. for 6 hours while under an atmosphere of nitrogen. The reaction mixture was then filtered to remove the precipitate that formed during the reaction from a brick red solution. The white precipitate was washed with DME until the washings ran through colorless. The washings were combined with the brick red solution and then the volatiles were removed from solution to yield 35.12 grams (57.6 mmol, 99%) of a brick red Mo(NAr) 2 Cl 2 (DME) product in which Ar is 2,6-diisopropylphenyl. The solid can be purified further by washing with cold pentane, if desired.
EXAMPLE II
In an inert atmosphere, i.e. under a blanket of nitrogen, 5.00 grams (14.7 mmol) of ammonium molybdate,(NH 4 ) 2 Mo 2 O 7 , were suspended in DME (70 mL) at room temperature. A solution of 11.90 grams of triethylamine (117.6 mmol) in 10 mL of DME was slowly added while stirring over a period of 5 minutes. There was no visible change in the solution. A solution of 27.10 grams of Chlorotrimethylsilane (250 mmol) in DME (20 mL) was then added while stirring over a period of 5 minutes. The solution became white and opaque. Finally, a solution of 7.13 grams of 2,6-dimethylaniline (59 mmol) in DME (15 mL) was added while stirring over a period of 5 minutes. The solution turned yellow. Additional white precipitate formed as the reaction progressed. The mixture was then heated to 60° C. for 8 hours while under an atmosphere of nitrogen. The reaction mixture was then filtered to remove the precipitate that formed during the reaction from a brick red solution. The white precipitate was washed with DME until the washings ran through colorless. The washings were then combined with the brick red solution and then the volatiles were removed from solution to yield 14.47 grams (29.1 mmol, 98%) of the brick red Mo(NAr) 2 Cl 2 (DME) product in which Ar is 2,6-dimethylphenyl. The solid can be purified further by washing with cold pentane, if desired.
EXAMPLE III
The procedure of Examples I or II is repeated using an equivalent amount of alkylammonium molybdate [Mo 8 O 26 ][CH 3 N(C 8 H 17 ) 3 ] 4 or [Mo 8 O 26 ][HN(C 12 H 25 ) 3 ] 4 to produce the Mo(NAr) 2 Cl 2 (DME) product in which Ar is as defined in Example I or II.
EXAMPLE IV
The procedure of Examples I, II or III is repeated using an equivalent amount of one of the following Lewis bases: tetrahydrofuran, pyridine, quinuclidine, and phosphines of the general formula P(R) 3 or (R) 2 PCH 2 CH 2 P(R) 2 where R is alkyl or aryl to produce the corresponding product, Mo(NAr) 2 Cl 2 (Lewis base) x where x =1 or 2 and Ar is as defined in Examples I or II.
EXAMPLE V
The procedure of Examples I, II, III or IV is repeated using an equivalent amount of bromotrimethylsilane to produce the corresponding product, Mo(NAr) 2 Br 2 (Lewis base) x where x =1 or 2 and Ar is as defined in Examples I or II.
EXAMPLE VI
The procedure of Examples I, II, III or IV is repeated in the absence of a coordinating Lewis base using one of the following non-coordinating solvents to produce the corresponding four-coordinate compound Mo(NAr) 2 (halogen) 2 in which Ar is as defined in Examples I or II: toluene, diethylether, dichloromethane or trichloromethane.
EXAMPLE VII
A Three Step preparation Employing Compounds of the Present Invention to Produce Corresponding Catalysts
An ether solution of neopentyl magnesium chloride (98.7 mmol) was added dropwise to a stirred solution of 30.00 grams of Mo(NAr) 2 Cl 2 (DME) (49.3 mmol), in which Ar is as defined in Examples I or II, in 500 ml of ether at -30° C., initiating the precipitation of MgCl 2 as indicated by a color change from red to orange. The reaction mixture was allowed to warm to 25° C. and was stirred for 3 hours. The resulting mixture was filtered through Celite, and the filtrate was concentrated and kept at -40° C. yielding 20.20 grams of an orange complex.
A prechilled solution of triflic acid (35.5 mmol) in DME (20 mL) was added dropwise to a solution of 7.00 grams of the orange complex in DME (200 mL) at -30° C. over a period of 10 minutes. Some pentane (15-30 mL) may be added to aid dissolution. The solution was allowed to warm up to room temperature and stirred for 3 hours. During this period the color changed from orange to dark yellow. The solvent was then evaporated to yield a yellow solid, which was then extracted with cold toluene (100-150 mL). The extract was filtered through a bed of Celite and the toluene removed from the filtrate to give 5.9 grams (65%) of the yellow complex.
0.95 grams of solid lithium tert-butoxide (11.8 mmol) was slowly added to a solution of 4.00 grams of the yellow complex in a mixture of 200 mL ether and 20 mL DME at -30° C. over a period of 10 minutes. The reaction mixture was allowed to warm to room temperature, stirred for 2 hours, and evaporated to dryness. The dark orange catalyst was extracted with 50 mL pentane and filtered through a bed of Celite. Evaporation of the solvent gave 2.54 grams of the catalyst complex.
It is to be understood that the embodiments of the invention which have been described are merely illustrative of applications of principles of the invention. Numerous modifications may be made by those skilled in the art without departing from the true spirit and scope of the invention. | Molybdenum and tungsten complexes useful as precursors for catalysts useful in the metathesis of olefins are disclosed. New compounds have the formula: M(R 1 ) 2 (NR 2 ) 2 (R 3 ) x . | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a non-provisional application relating to U.S. Provisional Application Serial No. 60/281,083 filed Apr. 3, 2001.
FIELD OF THE INVENTION
[0002] The present invention relates to devices for displaying packaged merchandise and, more particularly, to devices for loading packaged merchandise onto pegboard displays.
BACKGROUND OF THE INVENTION
[0003] Pegboard displays have been popular in the retail industry for displaying lightweight merchandise. Typically, merchandise packages are loaded individually onto pegboard displays. As a result, the conventional loading method is inefficient and time-consuming. Given the narrow profit margin on which most retail outlets operate, cost saving in this activity is desirable.
[0004] A recent solution to the problem mentioned above has been the “power panel”. The “power panel” is a ready made package of a number of loaded pegs in a box, which is simply hung up on a shelf wall. This displaying method has disadvantages in that it is expensive and does not provide means of recharge if there is a substantial difference in the sale of different items in the panel.
[0005] Various devices have also been developed for facilitating the loading of merchandise onto a display peg. For instance, U.S. Pat. No. 4,143,772 discloses a device having a plug which connects by a cord through a rear hole of a cup-shaped coupler. The plug and coupler can be joined together to form a loop that holds merchandise. The coupler can be separated from the plug and connected to the end of a display peg, so that the merchandise can slide onto the peg. Because the device needs to be uncoupled prior to the loading of the merchandise onto a display peg, the merchandise loading process is made rather complicated and/or inefficient.
SUMMARY OF THE INVENTION
[0006] The present invention overcomes the disadvantages and shortcomings of the prior art discussed above by providing a new and improved device for holding and facilitating the unloading therefrom of packaged merchandise onto a display peg. More particularly, the device includes a gathering mechanism for gathering together a group of packages such that hanging holes provided in individual packages are aligned so as to permit the gathered packages to be applied to a display peg together with the device. In accordance with the present invention, the gathered mechanism can include an open loop or a closed loop.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] For a better understanding of the present invention, reference is made to the following detailed description of exemplary embodiments, considered in conjunction with the accompanying drawings, in which:
[0008] [0008]FIG. 1 is a schematic view of a merchandise loading device constructed in accordance with a first embodiment of the present invention prior to the loading of merchandise packages onto a peg hook;
[0009] [0009]FIG. 2 is a schematic view of the loading device shown in FIG. 1 subsequent to the loading of the packages onto the peg hook;
[0010] [0010]FIG. 3 is a schematic view illustrating the use of the loading device shown in FIGS. 1 and 2 in connection with a different type of package;
[0011] [0011]FIG. 4 is a schematic view of a merchandise loading device constructed in accordance with a second embodiment of the present invention;
[0012] [0012]FIG. 5 a is a plan view of a merchandise loading device constructed in accordance with a third embodiment of the present invention;
[0013] [0013]FIGS. 5 b and 5 c are schematic views of the loading device shown in FIG. 5 a during the loading of merchandise packages onto a peg hook;
[0014] [0014]FIG. 6 a is a plan view of a merchandise loading device constructed in accordance with a fourth embodiment of the present invention;
[0015] [0015]FIG. 6 b is a side view of the loading device shown in FIG. 6 a;
[0016] [0016]FIG. 6 c is a schematic view of the loading device of FIGS. 6 a and 6 b used for pre-assembling merchandise packages into a shipping and loading unit;
[0017] [0017]FIG. 7 a is a perspective view of a merchandise loading device constructed in accordance with a fifth embodiment of the present invention;
[0018] [0018]FIG. 7 b is a schematic view of the loading device of FIG. 7 a used for pre-assembling merchandise packages into a shipping and loading unit;
[0019] [0019]FIG. 8 a is a perspective view of a merchandise loading device constructed in accordance with a sixth embodiment of the present invention;
[0020] [0020]FIG. 8 b is a schematic view of the loading device of FIG. 8 a used for pre-assembling merchandise packages into a shipping and loading unit;
[0021] [0021]FIG. 9 a is a perspective view of a merchandise loading device constructed in accordance with a seventh embodiment of the present invention;
[0022] [0022]FIG. 9 b is a schematic view of the loading device of FIG. 9 a during the loading of merchandise packages onto a peg hook;
[0023] [0023]FIG. 10 a is a perspective view of a merchandise loading device constructed in accordance with an eighth embodiment of the present invention;
[0024] [0024]FIGS. 10 b and 10 c are schematic views of the loading device shown in FIG. 10 a during the loading of merchandise packages onto a peg hook;
[0025] [0025]FIGS. 11 a and 11 b are schematic views of a merchandise loading device constructed in accordance with a ninth embodiment of the present invention;
[0026] [0026]FIG. 12 a is a perspective view of a merchandise loading device constructed in accordance with a tenth embodiment of the present invention;
[0027] [0027]FIGS. 12 b and 12 c are schematic views of the loading device shown in FIG. 12 a during the loading of merchandise packages onto a peg hook;
[0028] [0028]FIG. 13 a is a perspective view of a merchandise loading device constructed in accordance with an eleventh embodiment of the present invention;
[0029] [0029]FIG. 13 b is a schematic view of the loading device of FIG. 13 a used for pre-assembling merchandise packages into a shipping and loading unit;
[0030] [0030]FIGS. 14 a and 14 b are schematic views of a merchandise loading device constructed in accordance with a twelfth embodiment of the present invention;
[0031] [0031]FIG. 15 is a schematic view of a merchandise loading device constructed in accordance with a thirteenth embodiment of the present invention;
[0032] [0032]FIG. 16 is a schematic view of a merchandise loading device constructed in accordance with a fourteenth embodiment of the present invention;
[0033] [0033]FIG. 17 is a schematic view of a merchandise loading device constructed in accordance with a fifteenth embodiment of the present invention;
[0034] [0034]FIG. 18 is a schematic view of a merchandise loading device constructed in accordance with a sixteenth embodiment of the present invention;
[0035] [0035]FIG. 19 a is a perspective view of a merchandise loading device constructed in accordance with a seventeenth embodiment of the present invention;
[0036] [0036]FIG. 19 b is a sectional view of a merchandise package adapted for use in conjunction with the loading device of FIG. 19 a;
[0037] [0037]FIG. 19 c is a schematic view of the loading device of FIG. 19 a clipped to merchandise packages;
[0038] [0038]FIG. 20 is a schematic view of a merchandise loading device constructed in accordance with an eighteenth embodiment of the present invention; and
[0039] [0039]FIGS. 21 a and 21 b are schematic views of a merchandise loading device constructed in accordance with a nineteenth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0040] Referring to FIGS. 1 and 2, there is shown a merchandise loading/unloading device 10 constructed in accordance with a first embodiment of the present invention. The loading device 10 includes a band or strip 12 having a pair of ends 14 , 16 . The end 14 of the band 12 is threaded or otherwise inserted through hanging holes 18 of merchandise packages 20 so as to tie the packages 20 together as a single assembly or unit. More particularly, the packages 20 are tied together by the band 12 such that the holes 18 are aligned substantially linearly and are arranged (i.e., ganged up) adjacent to one another. The end 16 of the band 12 is securely attached (e.g., stapled) to the end 14 so as to form a closed loop for maintaining the packages 20 as a unit.
[0041] In use, the packages 20 are pre-assembled as a unit by the band 12 and then shipped to a retail outlet or store. In order to load the packages 20 onto a peg hook 22 at the retail outlet, with the band 12 held by a hand 24 of a user (see FIG. 1), the holes 18 of the packages 20 are aligned with a free end 26 of the peg hook 22 . The free end 26 of the peg hook 22 is then inserted through the holes 18 of the packages 20 by pulling the band 12 and hence the entire package unit toward a rear end of the peg hook 22 (see FIG. 2). This loading operation is facilitated by the band 12 , which functions to guide the packages 20 onto the peg hook 22 . After all of the packages 20 are loaded onto the peg hook 22 , the band 12 is disabled (e.g., cut, torn or pierced) and then removed, thereby releasing the packages 20 from one another to be dispensed individually from the peg hook 22 .
[0042] It should be appreciated that the present invention provides numerous advantages over the prior art discussed above. For instance, because the packages 20 are gathered together as a single assembly (i.e., the holes 18 of the packages 20 are aligned and ganged together) and then shipped to a retail outlet, loading of the packages 20 onto the peg hook 22 can be achieved in a simple and efficient manner. That is, the free end 26 of the peg hook 22 is aligned with the holes 18 of the packages 20 and is then inserted therethrough in a substantially single motion or step. Moreover, because only the band 12 is used for quick and easy loading of the packages 20 , the present invention provides a cost-effective loading method.
[0043] It should be noted that the present invention can have numerous modifications and variations. For instance, the band 12 can be replaced with any fastening members, such as links, cables, ropes, fasteners, clips, etc. In such circumstances, as used herein, the term “band” shall mean to include any such fastening members. The band 12 can also be made from a number of materials (e.g., metal or non-metal wires, plastic films, cardboard or paper bands). In this regard, it is noted that such fastening members can be designed to maintain the holes 18 of the packages 20 in their aligned and clustered form without directly engaging the holes 18 , as will be illustrated hereinbelow. The band 12 can also be made to form a loop in many different ways (e.g., the band can be glued, stitched, tied or clipped). Further, the band 12 can be used in connection with many different types of packages or items, such as polybags, paper or cardboard headers or boxes. For example, in FIG. 3, the band 12 is used in connection with polybags 28 .
[0044] FIGS. 4 - 21 b depict additional exemplary embodiments of the present invention. Elements illustrated in FIGS. 4 - 21 b which correspond, either identically or substantially, to the elements described above with respect to the embodiment of FIGS. 1 and 2 have been designated by corresponding reference numerals increased by an increment of one hundred in each succeeding embodiment. Unless otherwise stated, the embodiments of FIGS. 4 - 21 b is constructed, assembled and used in the same basic manner as the embodiment of FIGS. 1 and 2.
[0045] [0045]FIG. 4 shows a band or fastening member 112 constructed in accordance with a second embodiment of the present invention. More particularly, the band 112 is adapted for use in connection with boxes 130 (e.g., boxes for rolls of films) having tags 132 and holes 118 formed in the tags 132 . After the holes 118 have been aligned, the band 112 is wrapped around the boxes 130 for substantially immobilizing the boxes 130 with respect to one another. In this manner, the holes 118 are maintained in an aligned orientation so as to facilitate the loading of the boxes 130 onto a peg hook. In this regard, the holes 118 can be made to have a size that is greater than the cross-sectional area of the peg hook by about 10% or greater so as to facilitate the insertion of the peg hook into the holes 118 .
[0046] [0046]FIGS. 5 a - 5 c show a merchandise loading/unloading device 210 constructed in accordance with a third embodiment of the present invention. More particularly, the loading device 210 , which is made from a band or strip of any suitable materials (e.g., plastic), includes a unitary body 212 having opposing ends 214 , 216 , which are adapted to be releasably interlocked to one another. In this regard, the end 214 is provided with notches 234 , while the end 216 includes a slit 236 a and an opening 236 b connected to each other. Tabs 238 extend into the opening 236 b so as to form a throat 240 between the slit 236 a and the opening 236 b . A strip 242 , which has a width smaller than those of the ends 214 , 216 , connects the end 214 to the end 216 .
[0047] In use, the end 214 is passed through holes 218 of merchandise packages 220 and is then inserted into the slit 236 a . Thereafter, the end 214 is moved into the opening 236 b such that the tabs 238 are received in the notches 234 (see FIG. 5 b ). The throat 240 maintains the end 214 releasably locked in the opening 236 b by way of an interference fit. As a result, the packages 220 are kept as a pre-assembled unit during shipping to a retail outlet. In order to load the packages 220 onto a pegboard display, the end 214 of the loading device 210 is gripped by a user's hand 224 and is then lifted so as to suspend the packages 220 from the loading device 210 . Due to gravity, the holes 218 of the packages 220 are automatically aligned with one another and clustered together (see FIG. 5 b ). Next, the holes 218 of the packages 220 are aligned with a free end 226 of a peg hook 222 . The free end 226 of the peg hook 222 is then inserted through the holes 18 of the packages 220 by pulling the loading device 210 and hence the entire package unit toward a rear end of the peg hook 222 . After all of the packages 220 are loaded onto the peg hook 222 , the end 214 of the loading device 210 is unlocked from the end 216 and is then pull out from the holes 218 of the packages 220 (see FIG. 5 c ), releasing the packages 220 from one another to be dispensed individually from the peg hook 222 .
[0048] [0048]FIGS. 6 a - 6 c show a merchandise loading/unloading device 310 constructed in accordance with a fourth embodiment of the present invention. The loading device 310 includes a unitary strip 312 having a fold line 346 adjacent a center thereof. The strip 312 has a tapered end 314 and a flared end 316 . The flared end 316 has a plurality of crinkles 348 oriented in a direction substantially perpendicular to the longitudinal axis of the strip 312 for purposes to be discussed hereinafter. Pressure-sensitive adhesive materials 349 are applied to one side of the strip at one or both ends 314 , 316 so that when the strip 312 is folded along the fold line 346 , the tapered and flared ends 314 , 316 can removably adhere to each other. In this regard, the adhesive materials 349 can be any conventional pressure-sensitive materials. Alternatively, other adhesive materials or mechanisms can be used. The strip 312 is made from a chipboard material and has a strength sufficient to support merchandise packages 320 (see FIG. 6 c ) therefrom while loading. Alternatively, the strip 312 can be made from other suitable materials, such as paper, plastic, metal, etc.
[0049] With reference to FIG. 6 c , after the strip 312 is inserted through holes 318 of the packages 320 , the tapered and flared ends 314 , 316 are pressed to one another so as to be removably attached to each other. While being maintained as a pre-assembled unit by the strip 312 , the packages 320 are shipped to a retail outlet or store. After the loading of the packages 320 onto a peg hook, the flared end 316 is gripped by a user and then pulled away from the tapered end 314 . Because of the crinkles 348 , the flared end 316 curls away from the tapered end 314 and is hence easily detached from same in a “peeling” motion. In this regard, the amount of the adhesive materials 349 applied to the strip 312 should be sufficient to maintain the packages 320 as an assembled unit during shipping, while permitting easy manual peeling of the flared end 316 from the tapered end 314 subsequent to the loading of the packages 320 onto the peg hook. After detaching the flared end 316 from the tapered end 314 , the strip 312 is removed from the packages 320 .
[0050] [0050]FIGS. 7 a and 7 b show a merchandise loading/unloading device 410 constructed in accordance with a fifth embodiment of the present invention. The loading device 410 includes a strip 412 having a pair of ends 414 , 416 and a fold line 446 therebetween. The end 414 is tapered, while the end 416 has a slit 436 formed therein. The end 414 is sized and shaped so as to be removably received in the slit 436 so as to form a “locking” loop for merchandise packages 420 (see FIG. 7 b ). In this regard, the strip 412 is made from a material having a suitable strength and rigidity, such as cardboard.
[0051] In order to pre-assemble the packages 420 into a shipping and loading unit, the strip 412 is inserted through holes 418 of the packages 420 and folded along the fold line 446 . The tapered end 414 is then inserted into the slit 436 (see FIG. 7 b ). After the loading of the packages 420 onto a peg hook, the end 414 is pulled out from the slit 436 , and the strip 412 is removed from the packages 420 .
[0052] With reference to FIGS. 8 a and 8 b , there is shown a merchandise loading/unloading device 510 constructed in accordance with a sixth embodiment of the present invention. The loading device 510 includes a strip 512 having a pair of opposing ends 514 , 516 . The end 514 is tapered, while the end 516 has a slit 536 sized and shaped so as to receive the tapered end 514 for interlocking the ends 514 , 516 to each other by way of a frictional or mechanical fit. The strip 512 has a fold line 546 a located adjacent the center of the strip 512 and a fold line 546 b located between the fold line 546 a and the end 514 .
[0053] Referring to FIG. 8 b , after the end 514 of the strip 512 is passed through holes 518 of merchandise packages 520 , the strip 512 is folded along the fold lines 546 a , 546 b . The end 514 is then inserted into the slit 536 so as to form a triangular loop 550 . In this regard, the strip 512 is provided with sufficient stiffness for maintaining its triangular loop 550 . For instance, the strip 512 can be made from a material similar to stiff plastic strips used for packaging oversized packages. Alternatively, the strip 512 can be made from corrugated materials, such as those known as “Eflute” and “Ff-lute”. Because the triangular loop 550 is maintained by the engagement of the end 514 with the slit 536 , the end 514 is provided with a length sufficient to prevent accidental disengagement of the end 514 from the slit 536 during the shipping of the packages 520 . After the packages 520 are loaded onto a peg hook as a unit (using one or both of the ends 514 , 516 as a handgrip), a user's finger 551 is inserted into an opening formed by the loop 550 (see FIG. 8 b ), and the end 514 is pulled out from the slit 536 by the finger 551 . The strip 512 is then removed from the packages 520 .
[0054] [0054]FIGS. 9 a and 9 b show a merchandise loading/unloading device 610 constructed in accordance with a seventh embodiment of the present invention. The loading device 610 includes a strip 612 made from paper. Pressure-sensitive adhesive materials 649 are applied to one side of the strip 612 at ends 614 , 616 thereof. After the strip 612 is inserted through holes 618 of packages 620 , the ends 614 , 616 are brought together and pressed against one another for attachment. The adhesive materials 649 should have a sufficient bonding strength so as to prevent the packages 620 from being released from one another during shipping or storage. After the packages 620 are loaded onto a peg hook, the strip 612 is torn or otherwise disabled so as to permit withdrawal of the strip 612 from the packages 620 (see FIG. 9 b ). In this regard, the loop formed by the strip 612 can be sized and shaped to receive a person's finger. In this manner, the strip 612 can be torn after the loading of the packages 620 onto a peg hook by inserting a finger into the loop and pulling the strip 612 .
[0055] Now referring to FIGS. 10 a - 10 c , a merchandise loading/unloading device 710 , which is constructed in accordance with an eighth embodiment of the present invention, includes a rubber band 712 and a tab 752 fixedly attached to the rubber band 712 . Alternatively, the tab 752 can be completely eliminated or replaced with other mechanisms.
[0056] In order to pre-assemble merchandise packages 720 into a shipping and/or loading unit, the rubber band 712 is releasably tied around upper end 753 of the packages 720 . More particularly, a portion 754 of the rubber band 712 located opposite the tab 752 is passed through holes 718 of the packages 720 . The portion 754 is then passed through the rubber band 712 and pulled out so as to form a releasable knot 755 tying the upper ends 753 of the packages 720 to one another (see FIG. 10 b ). Due to the elasticity of the rubber band 712 , the knot 755 is maintained such that the packages 720 are kept as an assembled unit during shipping. After the packages 720 are loaded onto a peg hook (using the portion 753 as a handgrip), the tab 752 is gripped by a user and is then pulled so as to untie the knot 755 (as indicated by the arrow in FIG. 10 c ). In this manner, the loading device 710 can be quickly released from the packages 720 subsequent to loading.
[0057] It should be noted that the rubber band 712 can be replaced with bands made from other materials. For instance, the band 712 can be made from any rubber-like natural or synthetic materials, plastics, textile materials coated with rubber or latex materials, etc. Regardless of the material used for making the band 712 , the band 712 should preferably be provided with a sufficient coefficient of elasticity or friction so as to maintain the knot 755 during the shipping of the packages 720 to a retail outlet.
[0058] [0058]FIGS. 11 a and 11 b show a merchandise loading/unloading device 810 constructed in accordance with a ninth embodiment of the present invention. More particularly, the loading device 810 is in the form of a twist tie 812 . The twist tie 812 is used to tie packages 820 into a pre-assembled unit for shipping and loading. After the packages 820 are loaded onto a peg hook (using the twisted ends as a handgrip), the twist tie 812 is untied (see FIG. 11 b ) and withdrawn from the packages 820 .
[0059] With reference to FIGS. 12 a and 12 b , a merchandise loading/unloading device 910 constructed in accordance with a tenth embodiment of the present invention includes a unitary, flexible plastic body 912 . Alternatively, the body 912 can be made from other suitable materials, such as paper, rubber, metal, etc. The body 912 includes a pair of fingers 956 a , 956 b , which project in one direction, and a finger 956 c , which projects in an opposite direction. The finger 956 c is positioned between the fingers 956 a , 956 b . An opening 957 is also formed in the body 912 below the finger 956 c for purposes to be discussed hereinafter. The body 912 has a perimeter which forms a closed loop.
[0060] In order to assemble packages 920 into a shipping and loading unit, with the body 912 positioned on a front side 958 of the packages 920 , the finger 956 c is inserted through holes 918 of the packages 920 and placed on a rear side 959 of same. The fingers 956 a , 956 b are also placed over upper ends 953 of the packages 920 and are positioned on the rear side 959 (see FIG. 12 b ). As a result, the upper ends 953 of the packages 920 are retained by the fingers 956 a - 956 c , thereby maintaining the packages 920 as an assembled unit for shipping and loading. When properly assembled, the holes 918 of the packages 920 align with the opening 957 of the body 912 so as to permit the loading of the packages 920 onto a peg hook 922 together with the loading device 910 . After the packages 920 are loaded onto the peg hook 922 (see FIG. 12 c ), the loading device 910 is pulled in a forward direction (as indicated by the arrow in FIG. 12 c ). Due to the flexibility of the loading device 910 , the fingers 956 a - 956 c bend so as to permit quick release of the loading device 910 from the packages 920 .
[0061] Now referring to FIGS. 13 a and 13 b , there is shown a merchandise loading/unloading device 1010 constructed in accordance with an eleventh embodiment of the present invention. The loading device 1010 has a unitary wire-like body 1012 made from metal and bent into a predetermined shape so as to form a U-shaped loop 1050 at one end thereof and an inverted U-shaped loop 1060 at an opposite end thereof. The loop 1050 includes a free end 1061 spaced from the body 1012 to form a gap 1062 (i.e., the loop 1050 is open).
[0062] In use, packages 1020 are loaded onto the loop 1050 (see FIG. 13 b ). Because the gap 1062 is relatively small, it inhibits the release of the packages 1020 from the loop 1050 during shipping. With the loop 1060 used as a handgrip, the packages 1020 are loaded onto a peg hook. After loading, the packages 1020 are removed from the loading device 1010 through the gap 1062 .
[0063] With reference to FIGS. 14 a and 14 b , a merchandise loading/unloading device 1110 constructed in accordance with a twelfth embodiment of the present invention is shown. The loading device 1110 includes a substantially flat body 1112 having an upper end 1116 and a lower end 1114 . The body 1112 is made from a relatively stiff material, such as a plastic. A V-shaped notch 1163 is formed in the lower end 1114 of the body 1112 , while an opening 1164 is formed in the body 1112 between the upper and lower ends 1116 , 1114 and connected to the notch 1163 . The opening 1164 is sized and shaped so as to receive upper portions 1153 of merchandise packages 1120 . More particularly, the opening 1164 has an upper section 1165 , which extends toward the upper end 1116 of the body 1112 , and a lateral section 1166 , which extends at an angle with respect to the upper section 1165 . The loading device 1110 also has a corner 1167 located adjacent to the lateral section 1166 of the opening 1164 , as well as a perimeter forming an open loop.
[0064] In use, the upper portions 1153 of the packages 1120 are inserted into the notch 1163 . Due to the V-shape of the notch 1163 , the upper portions 1153 of the packages 1120 are funneled into the opening 1164 . When the upper package portions 1153 are placed in the opening 1164 (see the broken line representation of the body 1112 in FIG. 14 b ), the body 1112 is pivoted such that the notch 1163 moves away from the upper package portions 1153 so as to prevent same from being released from the opening 1164 (see the solid line representation of the body 1112 in FIG. 14 b ). More particularly, the upper package portions 1153 are positioned in the lateral section 1166 and the upper section 1165 of the opening 1164 , while the corner 1167 of the body 1112 is placed in holes 1118 of the packages 1120 . As a result, the body 1112 is inhibited from moving relative to the packages 1120 so as to maintain same as a unit during shipping and loading. After the packages 1120 are loaded onto a peg hook (using the corner diagonally opposite the corner 1167 as a handgrip), the body 1112 is pivoted back to its original position (see the broken line representation of the body 1112 in FIG. 14 b ) and is then removed from the packages 1120 . For instance, after the body 1112 is pivoted back to its original position, it can be twisted so as to increase the size of the notch 1163 for facilitating the removal of the upper package portions 1153 from the opening 1164 .
[0065] A merchandise loading/unloading device 1210 constructed in accordance with a thirteenth embodiment of the present invention is shown in FIG. 15. The loading device 1210 includes a strip 1212 made from a chipboard material and coated with polyester to strengthen the strip 1212 . The strip 1212 has a pair of ends 1214 , 1216 . The end 1216 has a slit 1236 sized and shaped so as to receive the end 1214 for assembling a set of merchandise packages 1220 into a shipping and loading unit.
[0066] [0066]FIG. 16 shows a merchandise loading/unloading device 1310 constructed in accordance with a fourteenth embodiment of the present invention. The loading device 1310 has an integral body 1312 having a closed loop construction and including a tongue 1368 and a pair of legs 1369 interconnected to the tongue 1368 . The tongue 1368 is sized and shaped so as to be inserted through holes 1318 of merchandise packages 1320 . The tongue 1368 also has a sufficient resiliency such that upper portions 1353 of the packages 1320 can be gripped by the tongue 1368 and the legs 1369 for maintaining the packages 1320 as a shipping and loading unit. In loading the packages 1320 onto a peg hook, an upper edge of the loading device 1310 can be used as a handgrip.
[0067] Now referring to FIG. 17, a merchandise loading/unloading device 1410 constructed in accordance with a fifteenth embodiment of the present invention has a rigid body 1412 made from plastic. Alternatively, other types of material can be used for the body 1412 . A tongue 1468 projects from the body 1412 in one direction, while tabs 1469 project from the body 1412 in an opposite direction. The tongue 1468 is sized and shaped so as to be inserted through holes 1418 of merchandise packages 1420 to be assembled into a shipping and loading unit. The tabs 1469 are adapted to inhibit the body 1412 from being released from the packages 1420 during shipping. In loading the packages 1420 onto a display peg, an upper edge of the body 1412 can be used as a handgrip. The body 1412 also has a perimeter forming a closed loop.
[0068] [0068]FIG. 18 shows a merchandise loading/unloading device 1510 constructed in accordance with a sixteenth embodiment of the present invention. The loading device 1510 is in the form of a binding clip 1512 similar, in construction, to a conventional binding clip. For instance, the clip 1512 has a unitary metal body 1570 , which forms a closed loop and which has a pair of legs 1571 . A spring member 1572 is connected to the legs 1571 so as to urge the legs 1571 against one another. Grip members 1573 are coupled to the legs 1571 for use in releasing same from one another. One or both of the grip members 1573 can also be used as a handgrip in loading merchandise packages 1520 onto a peg hook.
[0069] In use, the clip 1512 is mounted to upper portions 1553 of the packages 1520 . More particularly, after the packages 1520 are arranged such that holes 1518 of the packages 1520 are aligned with each another and clustered together, the clip 1512 is mounted to the upper portions 1553 so as to immobilize same with respect to one another. In this manner, while the clip 1512 is mounted above the holes 1518 and does not hence directly interact or engage with same, the holes 1518 remain aligned and clustered during shipping and loading.
[0070] [0070]FIG. 19 a shows a merchandise loading/unloading device 1610 constructed in accordance with a seventeenth embodiment of the present invention. The loading device 1610 is identical to the loading device 1510 of FIG. 18, except as discussed hereinbelow. The loading device 1610 has a pair of legs 1671 a , 1671 b . Tabs 1674 a project from the leg 1671 a , while tabs 1674 b project from the leg 1671 b . The tabs 1674 a , 1674 b are positioned such that when the loading device 1610 is in its closed position (i.e., when the legs 1671 a , 1671 b are urged against each other), each of the tabs 1674 a engages a corresponding one of the tabs 1674 b.
[0071] The loading device 1610 is adapted for use in connection with merchandise packages 1620 having openings 1675 in addition to mounting holes 1618 (see FIG. 19 b ). The openings 1675 are located above the holes 1618 . The openings 1675 are sized and shaped such that when the loading device 1610 is mounted to the packages 1620 , the tabs 1674 a can engage the tabs 1674 b through the openings 1675 (see FIG. 19 c ). In this manner, the tabs 1674 a , 1674 b inhibit the packages 1620 from being released accidentally from the loading device 1610 .
[0072] [0072]FIG. 20 shows a merchandise loading/unloading device 1710 constructed in accordance with an eighteenth embodiment of the present invention. The loading device 1710 has a construction similar to that of a conventional bobby pin. More particularly, the loading device 1710 has a unitary wire-like body 1712 having a pair of legs 1776 , at least one of which is long enough to function as a handgrip. The legs 1776 converge adjacent free ends thereof so as to restrict packages 1720 from being released accidentally during shipping. The body 1712 also forms an open loop.
[0073] Now referring to FIGS. 21 a and 21 b , a merchandise loading/unloading device 1810 constructed in accordance with a nineteenth embodiment of the present invention includes a unitary horseshoe-shaped body 1812 having ends 1814 , 1816 . The ends 1814 , 1816 are adapted to be releasably interlocked with one another so as to form a closed loop, as well as a handgrip. While the body 1812 is preferably made from a flexible plastic material, other materials can be used.
[0074] It should be noted that the present invention can have further modifications and variations in addition to those discussed above. For instance, two or more of the devices of the embodiments shown in FIGS. 1 - 21 b can be used in conjunction with one another to load packages onto a display peg. By way of example, each of the devices 510 , 610 of the embodiments shown in FIGS. 5 a - 6 c can be inserted through one of the openings 1675 of the packages 1620 illustrated in FIG. 19 b to form an assembled unit of packages. The devices 510 and 610 can be made as separate pieces or as an integral piece. Two or more pieces of an identical loading device can also be used simultaneously.
[0075] It will be understood that the embodiments described herein are merely exemplary and that a person skilled in the art may make many variations and modifications without departing from the spirit and scope of the invention. All such variations and modifications, including those mentioned above, are intended to be included within the scope of the invention as defined in the appended claims. | The present invention relates to a device for holding and facilitating the unloading therefrom of packaged merchandise onto a display peg. The device includes a gathering mechanism for gathering together a group of packages such that hanging holes provided in individual packages are aligned so as to permit the gathered packages to be applied to a display peg together with the device. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to a multiple quantum well infrared detector, and more particularly, to a multiple quantum well infrared detector incorporating a series of tightly coupled well groups.
2. Discussion of the Related Art
Infrared detectors have a wide range of applications typically for the detection of heat gradients in devices such as infrared security systems and thermal imaging systems. Known types of detectors include mercury cadmium telluride (HgCdTe) detectors and silicon extrinsic detectors for the detection of infrared photons. An HgCdTe infrared detector includes a P-I-N semiconductor which operates on the principle of detecting infrared photons by measuring electrons which are released from the valence band to the conduction band in the intrinsic layer from the absorption of the infrared photon energy. A silicon semiconductor detector also detects infrared radiation by absorption of infrared photons in which bound electrons in the impurity energy bands of the dopant atoms gain the absorbed photon energy. The electrons which absorb the photon energy are released into the conduction band enabling an electric field bias to direct the released electrons to specific terminal contacts where they can be measured. Both of these types of infrared detectors suffer the drawback that they cannot be effectively integrated with certain readout circuits incorporating field effect transistors (FET) which enable the detected photons to be imaged.
A multiple quantum well (MQW) infrared detector is known in the art which is able to integrate with the FET readout circuitry not compatible with the HgCdTe and silicon detectors discussed above. The conventional MQW is a single well device which incorporates an array of barrier and well layers, typically aluminum gallium arsenide (AlGaAs) and appropriately doped gallium arsenide (GaAs), in an alternating pattern forming a multiple of single well structures. A dopant electron bound in the well structure formed by the conduction band of the GaAs and AlGaAs must acquire enough energy from an absorbed infrared photon to reach the conduction band of the AlGaAs in order to be a free carrier measurable as induced current by infrared photon radiation. This single well type structure only provides a single allowable energy state within the well structure which can be occupied by an electron. This paucity of allowable energy states effects the likelihood that an electron will absorb enough photon energy to be released into the conduction band.
The conventional MQW, therefore, still suffers a number of drawbacks making it less efficient as a high performance infrared imaging device. Specifically, the single well MQW has a limited band width range of the infrared spectrum which it can detect. Further, the conventional MQW is substantially sensitive to the angle of incidence of the infrared photons. Consequently, the prior art MQW is limited as a high performance detector compatible with the circuitry of many readout devices, such as thermal imagers.
What is needed then is an infrared detector which is adaptable to readout circuitry, such as will be found in a thermal imager, and has a higher band width detection and is less sensitive to angle of incidence than its prior art counterpart. It is therefore an object of the present invention to provide such a detector.
SUMMARY OF THE INVENTION
Disclosed is a composite multiple quantum well infrared detector incorporating a plurality of tightly coupled well groups formed by a number of alternating barrier layers and well layers. In one preferred embodiment, the coupled wells are comprised of a series of alternating layers of GaAs and AlGaAs. In this arrangement the coupled wells are separated in groups between barrier layers of AlGaAs. At each end of the array of coupled wells are graded barrier layers providing sufficient ohmic contacts which enable the system to accept appropriate bias potentials and to be coupled to a desirable readout system for an imaging device. Each of the layers of GaAs and AlGaAs within the coupled well regions are generally only a few lattice layers thick.
In operation of the composite quantum well as defined above, an impinging photon will release an electron from the well region of the doped GaAs into the conduction energy band of the AlGaAs material. If the electron absorbs enough photon energy so that it can be released from the well region into the conduction band, it will act as a free carrier and add to the current flow of the device. Consequently, this current flow can be measured to determine the amount of incident infrared radiation. Since a bound electron is free to travel within the well region and the well walls are very thin, the electron is free to tunnel between the different well regions defined by the coupled well, and thus, it is able to exist in more energy states than would be possible in a single well structure. A configuration of this type enables the device to detect a broader band width, absorb more infrared photons and enable the structure to be integrated with imaging circuitry.
Additional objects, advantages, and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of the layers of an infrared detector, according to one embodiment of the present invention;
FIG. 1(a) is a layer representation of a coupled well section of one layer of the embodiment of FIG. 1;
FIG. 2 is an energy band diagram of the layer representation of the embodiment of FIG. 1;
FIG. 2(a) is an energy diagram of one section of the tightly coupled wells of FIG. 2; and
FIGS. 3 and 4 are graphs which illustrate the broadening of the single energy level of an isolated well into a band of 8 levels for 8 tightly coupled wells. The wavelength shift between graphs 3 and 4 illustrates the effect of increased well doping.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description of the preferred embodiments is merely exemplary in nature and is intended in no way to limit the invention or its application or uses.
First turning to FIG. 1, a sectional view of a composite MQW infrared detector 10, according to one preferred embodiment of the present invention, is shown. Detector 10 includes a bottom contact layer 12 on which a graded contact barrier layer 14, and a series of alternating blocking or barrier layers 16 and composite well layers 18 are formed. At the top of detector 10 opposite contact layer 12 a second graded contact barrier layer 20 and a contact layer 22 is formed.
Generally, contact layers 12 and 22 are formed of n-type doped GaAs (≅2×10 18 ) at a thickness of approximately 1000 angstroms. Graded contact barrier layers 14 and 20 are AlGaAs having an undoped region adjacent the first barrier layers 16 and a doped region adjacent contact layers 12 and 22, respectively. The composition of the AlGaAs of layers 14 and 20 are such that the energy bands line up with the GaAs contact layer 12 and 22 and the barrier layers 16 as will be described below. Barrier layers 16 are generally formed of AlGaAs at 30% Al and 70% Ga, and act as an insulative region between composite well layers 18. Composite well layers 18 are formed of a plurality of alternating AlGaAs barrier layers and GaAs semiconductor layers as will be described hereunder.
Barrier layers 16 and well layers 18 are generally formed on contact layer 12 by a process such as molecular beam epitaxy, as is well known in the art. In FIG. 1, only one barrier layer 16 and two composite well layers 18 are shown. It will be understood, however, that the number of alternating layers 16 and 18 is not crucial to the invention, and will differ for specific applications.
In a preferred embodiment, the graded blocking layers 14 and 20, adjacent contacts 12 and 22, respectively are graded AlGaAs blocking layers to form an acceptable ohmic contact with the GaAs contact layers 12 and 22. During the epitaxial growth process, layers 14 and 20 will be doped at an edge proximate to contact layers 12 and 22 and graded with decreasing dopants until they reach the barrier layers 16. Such a procedure provides a good ohmic contact between contact layer 12 and 22 and the alternating barrier layers 16 and well layers 18 such that electrons can readily make the transition out of these alternating layers. In addition, to make this structure more applicable to be connected to certain readout circuitry, it is known to include a buffer layer (not shown) of AlGaAs on top of tact layer 22 and an active layer (not shown) of a high electron mobility transistor (HEMT) or other similar transistor, known to those skilled in the art. These added layers further are applicable to make detector 10 compatible with FET readout circuitry.
Contact layers 12 and 22 are positioned to accept a bias potential from a voltage source (not shown). For most applications of this type of device, the bias potential will be approximately one-half volt. Applying a bias potential creates an electric field between contact layers 12 and 22 by which free charge carriers released by infrared photons in the doped regions of layers 18 will transfer measurable charge, as will be described below.
FIG. 1(a) is a exploded view of one composite well layer 18 of FIG. 1. As is apparent, each composite layer 18 is formed of its own alternating layer configuration comprised of heavily doped n-type GaAs layers 24 and AlGaAs barrier layers 26. In one preferred embodiment, each composite well layer 18 includes eight GaAs layers 24. Noticeably, barrier layers 26 are about one-half the width of doped layers 24. Typical dimensions of each GaAs layer 24 is eight lattice layers wide, which is equal to approximately sixteen monolayers or atomic layers. A typical thickness of each AlGaAs layer 26 is five lattice layers or 10 monolayers. The GaAs layers 24 are appropriately doped with a density of approximately 2×10 18 -1×10 19 dopant atoms, depending on specific applications. In this configuration, each layer 18 forms a tightly coupled composite well which has eight separate allowable energy bands (one for each well) as will be described below. The concentration of aluminum in the AlGaAs barrier layers is approximately 30% and the concentration of gallium is approximately 70%.
FIG. 2 shows a conduction band energy diagram 28 of infrared detector 10 as shown in FIG. 1. The bottom of the conduction band of contact layers 12 and 22 are shown as sections 34 and 36 of energy diagram 28. Sloped conduction band sections 38 and 40 represent the energy level of the contact barrier layers 14 and 20 adjacent the contact layers 12 and 22, respectively. Sections 42 and 44 of conduction band 28 represent the first AlGaA barrier layers 16 adjacent contact barrier layers 14 and 22. Section 30 of energy diagram 28 represents the composite well configuration of well layers 18. As is apparent, each section 30 contains eight closely coupled wells 46 and associated barriers 48. Conduction band wells 46 and associated barriers 48 represent GaAs well layers 24 and AlGaAs barrier layers 26, respectively. Section 32 represents the conduction band of the AlGaAs barrier layer 16 between each well layer 18.
Below the energy diagram 28, a number of dimensions are represented by reference letters. Namely, reference letter A represents the dimension of contact section 34 and is approximately 2000 angstroms wide. Reference letter B represents the part of the sloped section 38 which is doped relative to sections 34 and 36, and is approximately 180 angstroms wide. Reference letter C is the remaining distance of sloped section 38 which is undoped and is approximately 120 angstroms wide. Reference letter D represents the width of the first blocking section 42 before the first composite well and is generally about 300 angstroms wide. Reference letter E is the distance of each layer 16 represented by section 32 between the composite wells 18 and is generally about 850 angstroms wide. The opposite end of the energy line is set at approximately the same dimension.
FIG. 2(a) represents a blown up version of the energy band of the set of eight composite wells 30. Each well section 46 is the conduction band energy representation of GaAs and is represented by a distance F of approximately eight lattice layers wide. The barrier section 48 of the wells 46 are represented as the energy level of the conduction band of AlGaAs and is generally about five lattice layers wide as depicted by distance G. The valence band (not shown) is a certain energy distance below the well shaped conduction band of FIG. 2(a). For GaAs, this energy distance is approximately 1.5 electron volts from the bottom of the conduction band. For AlGaAs this distance is approximately 1.9 electron volts from the bottom of the conduction band. Approximately 80% of this difference is in the conduction band edge, the remainder is in the valence band edge. Therefore, the depth of the well is about 0.32 eV.
Typically for a single well, the well structure formed by the alternating layers of GaAs and AlGaAs will establish one allowable electron energy level within the well and a quasi-allowable electron energy level near the top of the well. If two of these wells are formed close enough together, then a dopant electron bound in the allowable energy state of one of the wells will be free to tunnel back and forth between the two wells and occupy either one of the two allowable energy levels. This type of behavior is represented by two allowable energy levels within a single well having a separate, but approximately the same, energy. In other words, the energy levels will be one on top of the other having a slightly different energy. Consequently, if eight wells are tightly coupled, as in the preferred embodiment discussed above, there are eight allowable energy levels, and electrons bound in any one of the wells can occupy any of the allowable states. Conceptually, this leads to a single well having a number of electrons in a range of energy levels. Therefore, there are more electrons which are able to absorb photon energy to be lifted to the conduction band of the device. This, in turn, leads to the ability of photons with lesser energy, those with longer wavelengths, to release a bound electron in the higher allowable states into the free electron states. The greater number of electrons also means the states are filled to higher quantum numbers leading to greatly improved absorption for photons travelling vertically.
The width of the well and the level of dopant electrons play significant roles in the range of photon wavelengths which can be detected. The width of the well sets the center frequency of the frequency range detectable by determining the lowest energy level of the conglomerate of acceptable energy levels within the well structure. By increasing the dopant, the allowable energy states are filled to a higher level and the average detectable wavelength is shifted within the band of wavelengths set by the width of the well. Therefore, the combination of the number of coupled wells plus the width of each well and the number of dopant electrons establishes the energy levels of the electrons relative to the top of the conduction band of the barriers, thus establishing the amount of extra energy needed to release an electron to be detected.
FIGS. 3 and 4 represent graphs of the detectable wavelength of an MQW detector according to one embodiment of the invention. The lower coordinate axis is the wavelength (λ) in microns (10 -6 ) of the infrared photons and the vertical axis (pe) is a logarithmic variable related to the probability of finding an electron at that energy value. FIG. 3 represents the band width detectable by an MQW according to one preferred embodiment of the present invention which has GaAs wells doped to 6×10 16 dopant atoms. FIG. 4 is the detectable infrared band gap of a MQW according to one preferred embodiment of the present invention in which the GaAs wells are doped to 2×10 18 . As is apparent in both FIGS. 3 and 4, there are eight spikes representative of the eight different wells in the preferred embodiment.
In view of the discussion above, an MQW infrared detector is achievable which detects a substantially wider band width of infrared energy over its single well prior art counterpart. Since the detector incorporates GaAs and AlGaAs, the structure is readily adaptable to FET readout circuitry. Further, this arrangement of composite wells enables the detector to be more sensitive to detect infrared photons.
The foregoing discussion discloses and describes merely exemplary embodiments of the present invention. Oneskilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that various changes, modifications can be made therein without departing from the spirit and scope of the invention as defined in the following claims. | This invention discloses a multiple quantum well infrared detector comprising a series of alternating layers of blocking layers and composite well layers. Each composite well layer is comprised of alternating layers of GaAs and AlGaAs forming a tightly coupled well group. The tightly coupled well group allows more allowed states for an electron released from the valence bands of the gallium arsenide semiconductor material. Consequently, there is a wider band width of detectable infrared radiation by the composite wall structure over the single well of the prior art. | 8 |
TECHNICAL FIELD
The present invention relates to the technical field of model airplane, especially to the technical field of an electric model airplane powered by front-mounted motor.
BACKGROUND ART
Model airplanes, especially the small model airplanes powered by front-mounted motor, mostly fly on a small simple field, and typically, there is no flat runway for the small model airplanes to take off and land, and the propeller during flying is quite liable to be impacted by plenty of obstacles. In the prior art, what is generally adopted is the manner that the propeller is directly fixedly connected with the motor power output shaft (including motor main shaft or power output shaft of driven gear of motor-powered reducing gear train), therefore, during flying, especially in the process of takeoff and landing of the model airplane, once the propeller is impacted by an obstacle, in milder case, the propeller is broken, and in more serious case, the motor main shaft is bent to be out of work, and even the model airplane will be damaged.
In order to protect the propeller, some model amateurs use two screws for fixing a cylinder on the motor output shaft to form a propeller cushion, the propeller is sleeved on the propeller cushion, and a rubber band is sleeved on the two screws to tightly press the propeller on the propeller cushion, thus the motor drives the propeller to rotate during normal operation, and when the propeller is accidentally impacted, the rubber band tying the propeller is stretched out and broken under the action of impact moment and the propeller can be separated from the propeller cushion so as to protect the propeller to a certain degree, FIG. 1 is a schematic diagram of the connection of such a structure.
It can be seen that the propeller protecting device in the form of the rubber band is characterized by tightly pressing the propeller on the propeller cushion by using the rubber band, and the rotation of the motor drives the propeller by means of frictional force. Obviously, the transfer of rotational torque between the motor and the propeller requires quite large frictional force, and such a frictional force requires quite large pressure from the rubber band, however, when the tension force of the rubber band is relatively large, the propeller is hardly separated from the propeller cushion; in order to guarantee that the propeller is relatively easily separated from the propeller cushion when being impacted, the tension force of the rubber band tying the propeller cannot be too large. Therefore, two technical requirements in this method, i.e. transferring the rotational torque of motor and protecting the propeller from being impacted to further avoid damage, are contradictory in this simple technical proposal, so this technical measure is unsatisfactory in propeller protecting effect in practice.
Owing to the above problem, the development of front-mounted motor power model is substantially restricted, especially in the aspect of small-sized airplane.
SUMMARY OF THE INVENTION
The technical problem to be solved by the present invention is to provide a propeller connector of electric model airplane, which can, on the premise of ensuring stable and firm connection between an electric power output shaft and a propeller in the model airplane to normally transfer electric power to the propeller, separate the propeller from the electric power output shaft in time in the case of accidental impact so as to put the propeller under effective protection.
Thus, the present invention provides a propeller connector of electric model airplane, which is used for connecting an electric-power output shaft with a propeller in an electric model airplane with the propeller, the propeller connector comprises two connectors, wherein one of the connectors is connected with the electric-power output shaft of the model airplane, and the other connector is connected with the propeller of the model airplane, one of the two connectors is an elastic component provided with an opening slot, and the two connectors are coaxially connected and can rotate together, but can be conveniently separated from each other when impacted by external force;
wherein, one of the two connectors has an inner cavity shaped as a drum, the maximal diameter of the cross-sectional circumcircle at the middle of the drum-shaped inner cavity is larger than those of the cross-sectional circumcircles at the bottom and the opening, and the other connector is shaped to be tightly enclosed by the inner cavity of the connector;
wherein, one of the two connectors is provided with a convex rib(s) corresponding to the opening slot on the other connector, and the number of the convex rib(s) is at least one and at most equal to the number of the opening slot(s) on the other connector; when the two connectors are connected with each other, the convex rib is embedded into the opening slot so that the two connectors can be located and connected instead of rotating relatively, thus torque transfer between the electric power output shaft and the propeller is completed; axially slidable fit state is formed between the convex rib and the opening slot, so the convex rib slides from the interior of the opening slot to the opening of the opening slot and is then separated from the opening slot when the two connectors are separated from each other under external force;
wherein, one of the two connectors has an inner cavity shaped as two connected drums, the diameter of the cross-sectional circumcircle at the middle of each drum-shaped inner cavity is larger than those of the cross-sectional circumcircles at the bottom and the opening, and the other connector is shaped as double drums that can be tightly enclosed by the inner cavity of the connector;
wherein, the width at the opening of the opening slot is larger than or equal to that at the other end of the opening slot, and the shape of the convex rib is matched with the opening slot;
wherein, the cross sections of the two connectors are centrosymmetrical.
wherein, the cross sections of the two connectors are round, elliptical or polygonal.
wherein, when the cross section is polygonal, the opening slot of the connector is located at the corner or sideline.
wherein, the connector connected with the propeller can be integrally injection-molded with the propeller.
wherein, the model is a motor-powered model airplane.
Since the propeller connector of the model airplane provided by the present invention is used for connecting the electric power output shaft (including motor shaft and final stage driven gear shaft of motor-powered reducing system) with the propeller, the propeller connector is divided into two separable connectors, with one being connected with the propeller and the other being connected with the electric power output shaft. Embedded locking between the two connectors is realized by means of elastic deformation of the connector material so as to transfer motor power to the propeller, and when the propeller is impacted, one of the connectors is pried owing to moment to pry the other connector immediately, so the loosening of the deformed connector leads to the release of the other embedded connector. Therefore, on the premise of keeping the propeller and the electric power output shaft rotating together, the damage to the motor-powered model airplane and its power system can be avoided when the propeller is impacted, thereby making an effective breakthrough on the technical bottleneck of electric model airplane with front-mounted power.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustrative schematic diagram of the propeller protecting connector adopting rubber band in the prior art;
FIG. 2 is an illustrative schematic diagram of the structure of the drum-shaped connector with round cross section in one embodiment of the present invention;
FIG. 3A is a schematic diagram of the section structure of the drum-shaped connector with round cross section in a connection state in one embodiment of the present invention;
FIG. 3B is a schematic diagram of the section structure of the drum-shaped connector with round cross section in a state that the two connectors are separated under external force in one embodiment of the present invention;
FIG. 4 is a schematic diagram of the longitudinal section structure of the drum-shaped connector with round cross section in one embodiment of the present invention;
FIG. 5 is a schematic diagram of the drum-shaped connector with elliptical cross section in one embodiment of the present invention;
FIG. 6 is a schematic diagram of the drum-shaped connector with square cross section in one embodiment of the present invention;
FIG. 7 is a schematic diagram of the drum-shaped connector with round cross section and having symmetrical secants in one embodiment of the present invention;
FIG. 8 is a schematic diagram of the drum-shaped connector with octagonal cross section in one embodiment of the present invention;
FIG. 9 is an exploded schematic diagram of the assembly of model motor, round-drum-shaped connector and propeller in one embodiment of the present invention;
FIG. 10 is a schematic diagram of the structure of the drum-shaped connector with round cross section in another embodiment of the present invention;
FIG. 11 is a schematic diagram of the structure of the drum-shaped connector with round cross section and trapezoidal opening slot and convex rib in further embodiment of the present invention;
FIG. 12 is a schematic diagram of the structure of the drum-shaped connector having a semi-drum-shaped structure in one embodiment of the present invention;
FIG. 13 is a schematic diagram of the structure of the drum-shaped connector having a double-drum-shaped structure in one embodiment of the present invention;
FIG. 14 is a schematic diagram of the longitudinal section structure of the drum-shaped connector having a double-drum-shaped structure in one embodiment of the present invention;
FIG. 15 is a schematic diagram of the integrally injection-molded structure of the propeller and the connector connected with the propeller in one embodiment of the present invention;
FIG. 16 is a schematic diagram of the integrally injection-molded structure of the propeller and the other connector connected with the propeller in another embodiment of the present invention
FIG. 17 is an exploded schematic diagram of the assembly of the model airplane having the propeller protecting connectors in one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Further detailed description is made below to the embodiments of the present invention with reference to the drawings.
The connector having the function of protecting the propeller of model airplane provided by the present invention is used for connecting the electric power output shaft (including motor shaft and final stage driven gear shaft of motor-powered reducing system) with the propeller, the propeller connector comprises two separable connectors, with one being connected with the propeller and the other being connected with the electric power output shaft. The basic working principle of the connector is as follows: embedded locking between the two connectors is realized by means of elastic deformation of the connector material so as to transfer motor power to the propeller, and when the propeller is impacted, one of the connectors is pried owing to moment to pry the other connector immediately, so the loosening of the deformed connector leads to the release of the other embedded connector.
The moment required by the separation of the two connectors when the propeller is impacted is not directly associated with the transfer of rotational torque of the motor, so the requirement of these two design elements can be satisfied relatively easily during design. As for specific design, at least one of the two connectors is an elastic connector and is provided with an opening slot, and naturally, the two connectors can also be elastic connectors; both the two connectors have centrosymmetrical cross sections, e.g. round, ellipse, or round plus one or several secants, or triangle, square, hexagon, octagon, polygon and the like, however, no matter which shape the cross sections are, the two connectors are round-drum-shaped in the longitudinal direction, with the maximal diameter of the cross-sectional circumcircle at the middle of the drum-shaped inner cavity being larger than those of the cross-sectional circumcircles at the bottom and the opening; one of the connectors should be provided with the opening slot, and one of the connectors may be tightly enclosed by the inner cavity of the other connector, the two interconnected connectors are integrally fusiform.
In the present invention, the transfer of torque between the electric power output shaft and the propeller is achieved in two typical ways: 1, the cross sections of the two connectors are designed as round and the connector with no opening slot arranged thereon is provided with a convex rib, i.e. protruding edge, the convex rib is embedded into the corresponding opening slot of the other connector so that the two connectors cannot rotate and are locked; 2, the cross sections of the two connectors are designed as ellipse, or triangle with round corners, or square with round corners, or polygon, or round plus one or several secants, etc., in this case, the connector with no opening slot arranged thereon can be provided with no convex rib, the edge of one connector is locked with the opening slot on the other connector so that the two interconnected connectors form a structure that cannot rotate, thus it can be ensured that the electric power output shaft is not separated from the propeller owing to rotation under normal situation. Quite apparently, in the second case discussed above, it is acceptable to arrange the convex rib on the connector with no opening slot arranged thereon, and in the case of polygon, when the number of sides of the polygon is enough to be close to round, the convex rib must be arranged to maintain tight connection between the two connectors during their rotation.
To make it clearer, in the following embodiments for illustrating the present invention, the connector connected with the propeller is referred to as connecting plug, and the connector connected with the electric power output shaft, such as motor output shaft, is referred to as connecting socket sleeve, in addition, the connecting plug is tightly enclosed by the inner cavity of the connecting socket sleeve to realize the connection therebetween in general, but this is merely for illustrative convenience and shall not be contemplated as the limitation to the scope of the present invention.
Under the situation that the cross sections of the two connectors are non-round and no convex rib is arranged, the diameter of the connecting socket sleeve is increased under the action of torque in the process of transferring motor torque after the two connectors are interconnected, so the connecting plug does not slip inside the connecting socket sleeve only if the motor torque causes the difference between the diameter of the connecting socket sleeve prior to deformation and the diameter thereof subsequent to deformation to be smaller than one of the follows: 1, the difference between elliptical long shaft and short shaft; 2, the difference between the distance from the vertex angles of doubled polygon to the center of circle and the distance from the sides to the center of circle; and 3, the difference between the distance from the circumference to the center of circle and the distance from the secants to the center of circle, in this case, the connectors can transfer the motor torque.
The desired value of the force when the propeller is separated from the connector can be calculated through different structural forms and different materials. Therefore, no mutual influence is generated between separating force and torque transfer. Thus both adequate torque and proper separating force can be obtained, that is to say, the propeller and the motor can be effectively protected during impact while enough power can be obtained.
In one embodiment of the present invention, the typical structure of the connecting socket sleeve is a drum-shaped structure with opening slot and round cross section of the inner cavity thereof; the typical structure of the connecting plug is a drum-shaped structure that can be tightly enclosed by the inner cavity of the connecting socket sleeve. FIG. 2 is an illustrative schematic diagram of the typical structure of the round-drum-shaped connector in one embodiment of the present invention, wherein the structure comprises a connecting socket sleeve 5 and a connecting plug 6 ; the connecting socket sleeve 5 is elastic and has an round-drum-shaped inner cavity with eight opening slots thereon, a shaft sleeve pipe 51 of the connecting socket sleeve is connected with the electric power output shaft; similarly, the connecting plug 6 is basically round-drum-shaped and is provided with at least one convex rib 61 thereon or convex ribs 61 thereon the number of which is equal to the number of the opening slots on the connecting socket sleeve, the convex ribs are corresponding to the opening slots on the connecting socket sleeve 5 in the aspect of position, the width of the convex rib 61 is smaller than that of the opening slot, a propeller cushion 62 is arranged at the front end of the connecting plug 6 , and the propeller can be fixed with the propeller cushion 62 the in such a manner of interference fastening, gluing, screwing and the like; when the connecting socket sleeve 5 is connected with the connecting plug 6 , i.e. the connecting plug 6 is embedded into the connecting socket sleeve 5 , and simultaneously, the convex ribs 61 of the connecting plug are embedded into the opening slots 52 , axially slidable fit state is formed between the convex ribs and the opening slots, so that the connecting plug 6 is locked inside the connecting socket sleeve 5 and cannot rotate, in order to transfer rotational torque of the motor to the propeller, however, in the process that the connecting socket sleeve 5 is separated from the connecting plug 6 because the propeller is impacted by external force, the convex ribs can slide from the interior of the opening slots to the openings of the opening slots, finally leading to the separation of the two connectors.
FIG. 3A is a schematic diagram of the section structure of the round-drum-shaped connector in a connection state, which illustrates the state that the connecting plug 6 having the propeller cushion 62 and the propeller shaft 63 is locked by the connecting socket sleeve 5 . FIG. 3B is a schematic diagram of the section structure of the round-drum-shaped connector in a state that the connecting socket sleeve is separated from the connecting plug under external force; it can be seen that, when the propeller is impacted by external force, the connecting plug 6 , the propeller cushion 62 and the propeller shaft 63 are under the action of a prying moment having pivot A, and the connecting plug is separated from the connecting socket sleeve 5 when deflecting by 14 degrees.
FIG. 4 is a schematic diagram of the longitudinal section of this typical round-drum-shaped connector, which illustrates important features of this typical round-drum-shaped connector, namely, it can be seen from the longitudinal section that both the inner cavity of the connecting socket sleeve and the cross section of the connecting plug in the connector are round, the diameter B-B 1 of the cross section at the middle of the connecting socket sleeve is larger than the diameters of the two end faces of the connecting plug: A-A 1 and C-C 1 ; the maximal diameter of the cross section at the middle of the drum-shaped inner cavity of the connecting socket sleeve is larger than the diameters of the cross sections at the bottom and at the opening.
In accordance with the working principle of such a connector discussed above, those ordinary skilled in this art would quite easily comprehend that, besides the shape of round drum, the inner cavity of the connecting socket sleeve and the cross section of the connecting plug may also be ellipse, and polygonal drum-shaped structure with N sides, e.g. triangle, quadrangle, hexagon, octagon and the like, wherein N is a number from 3 to infinite; only if the cross section is centrosymmetrical, for example, round with one or two secants. When the inner cavity of the connecting socket sleeve and the cross section of the connecting plug are polygonal drum-shaped structures, e.g. triangle, quadrangle, hexagon, octagon and the like, the opening slots on the connecting socket sleeve may be at the corner or sideline, and round corner transition may be formed at the corner. Different shapes of the cross section of the connector could result in different arrangements of the convex ribs, specifically, when the round cross section of the connector or the polygon with enough sides is close to round, slippage is generated between the two connectors in the process of transferring torque by an electric power rotary connection mechanism, so in this case, it is required to arrange at least one convex rib on one of the connectors to be corresponding to the opening slots on the other connector, and in other cases, the arrangement of the convex ribs on the connector with no opening slot thereon can be omitted.
FIG. 5 is a schematic diagram of the connector with elliptical cross section in one embodiment of the present invention; FIG. 6 is a schematic diagram of the connector with square cross section in one embodiment of the present invention, in which the connecting socket sleeve has local parts 135 on four sides having locking effect, opening slots, and round corners 134 having no locking effect, and circular arcs 137 and right-angled sides 136 of the connecting plug are tightly locked by the local parts 135 in the connecting socket sleeve. FIG. 7 is a schematic diagram of one embodiment of the present invention with round cross section and having symmetrical secants; FIG. 8 is a schematic diagram of the structure of the round-drum-shaped connector with octagonal cross section in the present invention, in which round corners are arranged at the corners of the inner cavity of the connecting socket sleeve 5 and at eight corners of the connecting plug 6 , and the octagonal connecting plug can be provided with no convex rib. The structures in such shapes also have the function of transferring rotational torque between the electric power output shaft and the propeller and the function of protecting the propeller when the propeller is impacted.
Thus, those ordinary skilled in this art could comprehend some modified structures of the present invention quite easily without any creative effort, which can be not limited to the section shapes listed above as long as the cross section of the connector is centrosymmetrical and which can realize the functions of the present invention, thus these modified structures of the present invention are contemplated as being within the scope of the present invention.
FIG. 9 is an exploded schematic diagram of the assembly of motor, typical round-drum-shaped connector and propeller in one embodiment of the present invention, in which a motor 1 , a connecting socket sleeve 5 , a connecting plug 6 and a propeller 2 are included and which clearly shows the total structure and the assembly steps of the typical round-drum-shaped connector and the electric power of model airplane, namely, the motor output shaft and the propeller.
With regard to the connections of the two connectors with the propeller and with the electric power output shaft, in this specification, the connector connected with motor is generally the connecting socket sleeve and the connector connected with the propeller is the connecting plug. It can be known from the aforementioned embodiments that the typical round-drum-shaped connector is the connecting socket sleeve on which uniform opening slots are distributed, and the corresponding convex ribs are arranged on the connecting plug, so those skilled in this art would be aware of other modified structural forms of the two connectors quite easily.
FIG. 10 is a schematic diagram of the structure of the round-drum-shaped connector in another embodiment of the present invention, in which a connecting plug 8 is sleeved with a shaft sleeve 81 and an electric output shaft, a connecting socket sleeve 9 and a propeller cushion 92 are connected with the root of the propeller, the structures of the connectors are just opposite, in the horizontal direction, to those of the connecting socket sleeve and the connecting plug in FIG. 2 , and its propeller protecting function is the same.
FIG. 11 is also a typical structural form, in which 7 is the round-drum-shaped connecting socket sleeve with convex ribs, the diameter of the opening of the connecting socket sleeve is smaller than that of the middle part of the inner cavity, and the connecting socket sleeve is rigidly structured. A connecting plug 77 is provided with opening slots 76 so as to be elastic, and this structural form is characterized in that the outer diameter of the connecting plug 77 is under shrinkage deformation in the process that the connecting socket sleeve is separated from the connecting plug. When the propeller is impacted, a prying moment acts on the connectors, the connecting plug is separated outwards from the connecting socket sleeve, and when the maximal designed outer diameter of the connecting plug 77 is deformed to be less than the diameter of the opening of the connecting socket sleeve, the connecting plug 77 can be separated outwards from the connecting socket sleeve 7 ; in the proposal that the inner cavity of the connecting socket sleeve is provided with inward convex ribs, dimensional coordination between the convex rib and the opening slot must comply with the follows: when the maximal designed diameter of the connecting plug is changed to the opening of the connecting socket sleeve, the width of the convex rib should be less than the width of the shrunk opening slot; it can be obtained through analysis that the opening of the opening slot has larger degree of deformation than the bottom of the opening slot during the shrinkage deformation of the opening slots on the connecting plug, thus it is more reasonable to design the opening slots and the convex ribs in the trapezoidal structure: the width of the opening of the opening slot is larger than that of the bottom of the opening slot, and the width of the convex rib at the opening of the rigid connecting socket sleeve is smaller than the dimension of the bottom of the connecting socket sleeve.
In the round-drum-shaped connector having the connecting plug 77 with the opening slots 76 thereon, the width of the opening of the opening slot 76 of the connecting plug is larger than the trapezoid having the same width as the bottom; an inner cavity 74 of the connecting socket sleeve 7 is provided with convex ribs 72 in the trapezoidal shape, and the width of the convex rib 72 at the opening of the connecting socket sleeve is smaller than that of the bottom of this convex rib; the connecting plug 77 is pried under the action of moment to slide out of the connecting socket sleeve 7 , the process of sliding gradually from the maximal diameter part at the middle of the connecting plug 77 to the opening of the connecting socket sleeve is the process that the outer diameter of the connecting plug 77 is gradually shrunk to the maximal variable, the width of the original trapezoidal opening slot is changed to be minimal, at this moment, the trapezoidal convex rib is shrunk into the opening slot with the minimal width to generate an axially slidable fit state therewith, thus the connecting plug 77 can be separated outwards from the connecting socket sleeve 7 with fixed diameter.
The proposal of the drum-shaped structure on the superposing form in a height direction is the same as the aforementioned principle.
FIG. 12 is a schematic diagram of the structure of the drum-shaped connector, with a half-height drum-shaped structure superposed, in one embodiment of the present invention, in which a drum-shaped connecting plug 106 is a drum-shaped structure with full height, and a drum-shaped connecting plug 107 is a drum-shaped structure with half height and is jointed with a drum-shaped connecting socket sleeve 108 in this figure, the half-height drum-shaped part of the connecting plug 107 acts only on the stability of the locking between the connecting socket sleeve and the connecting plug in this figure, but has no enhancement on the locking function of the connecting socket sleeve.
FIG. 13 is a schematic diagram of the structure of two superposed drum-shaped connectors with the same diameter in one embodiment of the present invention. FIG. 14 is a schematic diagram of the longitudinal section of the two superposed drum-shaped connectors with the same diameter, shown as FIG. 13 and FIG. 14 , one drum-shaped structure 127 having the larger-diameter cross section and another drum-shaped structure 126 having the smaller-diameter cross section are superposed in a height direction, and R 1 is a circular arc line having the radius from the center of circle A to the opening of the larger-diameter drum-shaped socket sleeve in FIG. 14 ; and R 2 is a circular arc line having the radius from the center of circle A to the maximal diameter part of the smaller-diameter drum-shaped structure 126 in FIG. 14 . In such a proposal of superposed structure, R 2 is smaller than R 1 , so when the propeller is impacted, the connecting plug is separated outwards from the connecting socket sleeve under the action of a prying moment taking a point specified by an array A as pivot, and for the same reason, the connecting plug can be separated outwards from the connecting socket sleeve at a time, so this structure has the same basic functions as the proposals shown as the aforementioned schematic diagrams.
The propellers of a majority of motor-powered small-sized model airplanes are manufactured by plastic injection molding, the connector having the propeller protecting function can be integrally injection-molded with the propeller to form a novel propeller product. FIG. 15 shows the integrally injection-molded structure of a propeller 21 and a connecting plug 26 , and FIG. 16 shows the integrally injection-molded structure of a propeller 22 and a connecting socket sleeve 25 .
FIG. 17 is an exploded schematic diagram of the assembly of the power system of the electric power model airplane including propeller protecting connectors 5 , 6 , a propeller 2 and a fairing 7 in one embodiment of the present invention.
Introduction to the test condition of propeller connectors and a motor having the propeller protecting function: the shape is just as the combination of the connectors in FIG. 2 , and basic data is as follows: the maximal inner diameter of the connecting socket sleeve is 10mm, when the propeller is impacted, the moment required by separating the connecting plug from the connecting socket sleeve is 550 to 600g/cm, and the maximal axial pulling-out force of the connecting plug is 1800g. The test is conducted on a remote-control N50-motor-powered model airplane having the weight of 65g, the wingspan of 500mm and the diameter of 107mm for a front-mounted propeller. During various flying movements of the model airplane, such as climbing, sharp turn, level flight and steep descent, the connectors having the propeller protecting function can guarantee normal operation of the propeller, and no matter whether the model airplane lands on rough meadow or flat cement road, the propeller will be separated from the motor the moment the propeller collides with cement road surface, meadow or branches, thus the propeller is protected effectually and the damage to the motor and the model airplane is avoided. However, under the condition of the same model airplane and flying field, the propeller is directly fixed with the motor power output shaft of the model airplane, so the propeller of the model airplane will be bent or broken when the propeller collides with cement road surface, trips over meadow or is impacted by branches in the process of landing, and this generally causes the motor output shaft to be bent, and accordingly, to be out of work.
While the present invention is described with reference to embodiments, those ordinary skilled in this art would understand that, many modifications and variations can be made to the present invention without departing from the spirit and essence of the present invention, and the scope of the present invention shall be defined by claims attached. | A propeller connecting piece for electric model airplane, for connecting an electric-power output shaft with a propeller in an electric model airplane with the propeller, characterized in that the propeller connector comprises two connectors, wherein one of the connectors is connected with the electric-power output shaft of the model airplane, and the other connector is connected with the propeller of the model airplane, one of the two connectors is an elastic component provided with an opening slot, and the two connectors are coaxially connected and can rotate together, but can be conveniently separated from each other when impacted by external force, so as to put the propeller under effective protection. | 0 |
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates to a chromatofocusing and multiplexed capillary gel electrophoresis system for the two-dimensional separation of proteins and to a method of using it.
BACKGROUND OF THE INVENTION
[0002] Protein mixtures can be difficult to resolve using only one separation technique. Therefore, two-dimensional or multidimensional separations are sometimes used. Two-dimensional refers to the fact that the sample mixture is partially resolved (in one dimension) using one separation technique, then the output from this first separation is further resolved (in the second dimension) using a second separation technique. The number of dimensions is equal to the number of separation techniques employed. The sample properties that determine sample separation in the first dimension should be different from those properties that determine sample separation in the second dimension in order to maximize separation resolution. If the sample properties that determine separation are totally different in both dimensions, the dimensions are said to be orthogonal. This is desirable since it enhances separation resolution.
[0003] An example of a two-dimensional separation is described by Liu and Le Van in U.S. Patent Application Publication U.S. 2002/0033336 A1. The first dimension is high-performance liquid chromatography (HPLC) and the second dimension is a plurality of electrophoresis columns. Liu and Le Van also disclose a separation where the first dimension is isoelectrical focusing and the second dimension is an array of capillary gel electrophoresis channels.
[0004] Another example of a two-dimensional separation is described by Wiktorowicz and Raysberg in U.S. Pat. No. 6,013,165. In one embodiment of the invention, the first dimension is gel electrophoresis to separate samples by size and charge and the second dimension is isoelectric focusing.
[0005] Akins in U.S. Patent Application Publication No. US 2002/0153252 A1 describes further examples of 2-dimensional systems in which the first dimension is cationic electrophoresis and the second dimension is one of denaturing electrophoresis, electrophoresis subsequent to proteolytic cleavage, isoelectric focusing non-equilibrium pH gel electrophoresis or immobilized pH gradient electrophoresis.
[0006] The present invention is an orthogonal two-dimensional system employing chromatofocusing (CF) as the first dimension and multiplexed capillary gel electrophoresis (MCGE) as the second dimension. These two dimensions are totally orthogonal, unlike some of the others above mentioned and, therefore, result in a higher degree of separation resolution.
[0007] For reasons not fully known to the inventors, no one has previously combined CF and MCGE as the two dimensions. Perhaps this is because they are relatively new techniques, their orthogonal nature has not been appreciated, and some of the buffer reagents used for each have been incompatible. Applicants have, however, discovered that the combination of CF and MCGE achieves good resolution in minimum time and can be used to advantage.
[0008] The widely accepted technique for protein analysis is traditional 2D gel electrophoresis. This is a method for the separation and identification of proteins in a sample by displacement in 2 dimensions oriented at right angles to one another. The first dimension is isoelectric focusing (IEF) which separates proteins according to isoelectric point (pI) differences while the second dimension is polyacrylamide gel electrophoresis (SDS-PAGE) which separates proteins according to their sizes.
[0009] However, there are many disadvantages related to the 2D gel electrophoresis. It is labor intensive, time consuming and poorly automated. Usually it takes several days to complete an analysis. Proteomics research requires the development of new techniques that have the following features: (1) increased resolving power and speed, (2) the ability to analyze proteins with varied properties (isoelectric points, molecular weights, hydrophobicities), (3) simplicity and automation and (4) the ability to perform high throughput analysis.
[0010] CF coupled with MCGE is a good alternative for the traditional 2D gel electrophoresis. It provides higher speed (it takes several hours to complete an analysis instead of several days in traditional 2D gel electrophoresis), automation and high throughput. The data output is directly comparable to the traditional 2D gel electrophoresis results.
[0011] CF is a form of ion-exchange chromatography. The objective of CF is to elute proteins from a column in order of their isoelectric points. An isoelectric point is the pH at which the net charge on a molecule in solution is zero. A weak anion (in anion CF) exchange column is equilibrated with a low ionic strength buffer at a high pH. The sample protein is loaded onto the column. Proteins are bound to the anion exchanger at the high pH. A pH gradient is then produced by adding a second, lower pH buffer. This buffer contains species that have a wide range of pK a s. The range of pK a s provides level buffer capacity across the entire pH range of the gradient. As the pH on the column decreases, protein positive charges become stronger and there is less interaction between the column and the protein. Eventually, the protein does not interact with the column and it elutes. The bound proteins are eluted in order of their isoelectric points, from high to low.
[0012] High performance MCGE has rapidly become an important analytical tool for the separation of a large variety of compounds ranging from small ions to large biological molecules. MCGE is used for general separations, enantiomeric separations, protein separations, the peptide mapping of proteins, amino acid analysis, nucleic acid fractionation and the quantitative measurement of acid dissociation constants (pK a values) and octanol-water partition coefficients (log P ow values).
[0013] What all these MCGE applications have in common is the measurement of the mobility of chemical species in a capillary tube as a means of identifying it. To perform a conventional separation, a capillary tube is filled with a buffer solution, a sample is loaded into one end of the capillary tube, both ends of the capillary tube are immersed in the buffer solution and a large potential is applied across the capillary tube. The sample components are separated electrophoretically as they migrate through the capillary tube. In a UV detection system, a section of capillary tube is irradiated with a UV light source. A photodetector detects the light that passes through the tube. When a UV absorbing sample component passes through the irradiated portion of the capillary tube, the photodetector detects less passed light (indicating absorbance). In this way an electropherogram, a plot of absorbance versus time, can be produced.
[0014] The rapid development of biological and pharmaceutical technology has posed a challenge for high-throughput analytical methods. For example, current development of combinatorial chemistry has made it possible to synthesize hundreds or even thousands of compounds per day in one batch. Characterization and analysis of such huge numbers of compounds has created a bottleneck. Parallel processing (i.e., simultaneous multi-sample analysis) is a natural way to increase the throughput. Unlike high-performance liquid chromatography or gas chromatography, it is practical to build a highly multiplexed CE instrument that can analyze dozens of samples simultaneously. Such a system has been disclosed in PCT Application WO 01/18528A1.
[0015] There is a continuing need for development of multidimensional separation techniques of high speed and high resolution. To date, no one has combined chromatofocusing (CF) and multiplexed capillary electrophoresis (MCGE). It is believed that this is because both techniques are relatively new; chromatofocusing was disclosed in 1978 and MCGE is even younger and because their orthogonal relationship has not heretofore been appreciated for use in two-dimensional techniques.
[0016] Another reason that CF and MCGE have not been combined for protein separation is that buffers used for CF often interfere with the absorption detection employed with MCGE. Protein absorbance is stronger at a wavelength of 214 nm than 280 nm. Therefore, 214 nm is preferred for MCGE detection systems because it allows greater sensitivity of detection. However, typical CF systems use absorbance detection for proteins at 280 nm. The reason is that the buffer used, commonly Polybuffer™ available from Amersham BioSciences, strongly absorbs at 214 nm. If Polybuffer™ is used in conjunction with a detection system at 214 nm, the absorbance distorts the baseline and hinders detection of proteins. In short, one reason the two techniques have not been combined is a lack of a buffer that will work well in both systems, preferably at 214 nm. The applicants have discovered such a buffer.
[0017] The applicants have discovered that multidimensional separations combining CF and MCGE as herein described have the advantage of being totally automatable, thus achieving certain labor efficiencies. Furthermore, it is advantageous to combine CF rather than isoelectric focusing, as has been done in the past, with MCGE. This is because CF has the capacity to handle large samples. This is beneficial to the second dimension, MCGE, for detection and separation. If the amount of sample from the first dimension is too low, there can be sensitivity problems in the second dimension.
[0018] Additionally, it is particularly advantageous to combine CF with MCGE because the output from CF is a large number of aliquots of solution. With MCGE, due to the multiplexing, all the aliquots can be analyzed simultaneously in separate capillary tubes.
[0019] The primary objective of the present invention is to design a two-dimensional, orthogonal separation technique that combines CF and MCGE to provide high speed and high resolution separations. The method and manner of achieving this primary objective as well as others will become apparent from the detailed description that follows.
BRIEF SUMMARY OF THE INVENTION
[0020] This invention relates to a two-dimensional system of separation and a method for separating sample components, particularly proteins. The first dimension is chromatofocusing and the second dimension is capillary gel electrophoresis. The invention is two-fold in its aspect: first is the integration of CF and MCGE for protein separation. Second, and complementary to the first, is a buffer appropriate for use in an integrated CF/MCGE system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] [0021]FIG. 1 presents a schematic diagram of a chromatofocusing system integrated with a multiplexed capillary electrophoresis system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] The invention, as hereinbefore explained, is a CF system integrated with an absorbance-based MCGE. The invention system and method are for the separation, detection and identification of chemical species, particularly proteins.
[0023] Refering to FIG. 1, the column 16 is initially equilibrated with a starting solution adjusted to high pH. After equilibration, the sample is injected into the column 16 through the sample injector 14 . The sample injector 14 is the same as used in high performance liquid chromatography. After sample injection, the pump 12 pumps lower pH buffer solution 10 towards the column 16 . The column 16 is filled with a weak anion exchange resin. The sample proteins are separated in the column according to isoelectric point. Past the column is the detector 18 . The detector measures the light absorption of proteins at a given wavelength, preferably 214 nm. Next in line is the pH monitor 20 that measures the pH of the solution after it exits the column. The sample is then collected with a programmable sample handling system 38 that collects fractions during certain time intervals, if operated in time mode, in a 96-well titer plate. The sample handling system 38 also has the following functions: liquid handling including liquid reagent addition, and sampling positioning for introducing a sample into the MCGE system. After finishing the required sample treatment, the titer plate is sent into the MCGE system for the second dimension separation and analysis. The transfer of sample can be done by human interference, but preferably by a robot arm for complete automation between injection of the sample in CF and data analysis with MCGE.
[0024] The inlet ends of capillary tubes 24 are immersed in a buffer solution in the sample tray 22 . Some of the buffer solutions also contain the fractions from the first dimension of the separation. The samples are loaded into the capillary tubes. A large potential difference is applied-across the capillary tubes 24 and the proteins are separated electrophoretically.
[0025] The light beam originates in the light source 28 and then travels through the collimating lens 30 , the planar array of capillary tubes 24 , the flat-field lens 32 , the optical filter 36 and is collected in the detector. The protein samples are detected by light absorption when they pass through the capillary tubes in the area illuminated by the light source.
[0026] The distance between the area where light is emitted from the light source 28 and the planar array of capillary tubes 24 is not critical to the practice of the present invention. However, the shorter the distance between the area where light is emitted from the light source 28 and the planar array of capillary tubes 24 , the more light is received by the planar array of capillary tubes. The more light that the planar array of capillary tubes receives, the more sensitive is the detection.
[0027] Preferably, the distance between the planar array of capillary tubes 24 and the detector 34 is at least about 10 times, more preferably, at least about 100 times, a cross sectional distance of a capillary tube measured orthogonally to the plane of the planar array of capillary tubes 24 . The critical feature is that the distance must be such that the entire array is visible and in focus. Thus, the distance between the planar array of capillary tubes 24 and the detector 34 is preferably from about 1 centimeter to about 100 centimeters, more preferably from about 3 cm to about 40 centimeters, and most preferably from about 20 centimeters to about 40 centimeters.
[0028] By “capillary tubes” 24 is meant at least 3 or more, preferably at least about 10, more preferably at least about 90, and desirably as many as can be accomodated by the system described herein. The capillary tubes 24 allow the passage of light from the light source 28 through the walls of the capillary tubes 24 facing the light source 28 , through the samples in the capillary tubes 24 , and through the walls of the capillary tubes 24 facing the detector. Thus, the walls of the capillary tubes 24 are desirably transparent, although, in some instances, the walls of the capillary tubes 24 can be translucent. It is not necessary for the entirety of the walls of the capillary tubes 24 to allow the passage of light from the light source 28 as described above as long as at least a portion of the walls of the tubes allow the passage of light from the light source 28 such that the samples in the capillary tubes 24 are irradiated and light that is not absorbed by the absorbing species and samples is detectable by the detector.
[0029] In general, the capillary tubes 24 should have smooth surfaces and uniformly thick walls and be made of a material transparent over the range of wavelengths of light absorbed by an absorbing species in the sample, the absorbance of which is to be detected or measured. Preferred materials for capillary tubes 24 include, but are not limited to, plastics, quartz, fused silica and glass. The cross-section of a capillary tube 24 is not critical to the present invention. However, the smaller the cross-section of the capillary tube 24 , the more useful is the capillary tube 24 in highly multiplexed applications as a greater number of capillary tubes 24 can be used in a smaller amount of space. Similarly, the thickness of a walls of the capillary tubes 24 is not critical to the present invention. The walls should be of sufficient thickness as to maintain the structural integrity of the capillary tube 24 , yet not so thick as to adversely impede the passage of light through the capillary tube 24 . The shape of the capillary tube 24 also is not critical to the present invention. The capillary tube 24 can have any suitable shape. However, the preferred size and shape of the capillary is 150 μm outside diameter, 75 μm inside diameter and circular in shape. Desirably, the shape of the capillary tube 24 is conducive to being closely packed and minimizes the generation of stray light by the container. The capillary tubes 24 are preferably from about 10 cm to about 200 cm long.
[0030] Capillary tubes 24 are commercially available by a number of sources including Polymicro Technologies, Inc., Phoenix, Ariz. The capillary tube 24 is preferably coated with a polymer such as polyimide so that it is mechanically stable. The coating must be removed in the region to be irradiated by the light source 28 . An excimer laser can be used to remove the polymer coating.
[0031] Preferably, the capillary tubes 24 in the planar array are arranged substantially parallel and adjacent to each other. Adjacent capillary tubes 24 can be physically touching each other along all or a portion of their lengths, although slight inconsistencies in capillary wall diameter or other features of the array can prevent them from being in contact along their entire lengths.
[0032] The electrical potential used for electrophoretic separation is not critical to the invention. A typical potential generated by the high voltage power 26 supply ranges from 5,000 to 30,000 V.
[0033] If a large amount of heat is generated during the method, particularly in the vicinity of the planar array of capillary tubes 24 , cooling should be employed to dissipate the heat.
[0034] Excessive heat can lead to mechanical vibrations between adjacent capillary tubes 24 , which, in turn, can lead to excess noise. Fans can cool the capillary tubes 24 .
[0035] The detector 34 can comprise any suitable means of detecting absorption. Preferably, the detector 34 comprises a plurality of absorption detection elements, such as a plurality of photosensitive elements, which desirably are positioned in a linear array, although a two-dimensional image array detector can be used. Desirably, the detector 34 is parallel to and in-line with a linear array of capillary tubes 24 . The detector 34 is desirably rigidly mounted to reduce flicker noise.
[0036] Preferably, the detector 34 is a linear photodiode array (PDA). Desirably, the PDA incorporates a linear image sensor chip, a driver/amplifier circuit and a temperature controller, which desirably thermoelectrically cools the sensor chip to a temperature from about 0° C. to about −40° C. Lowering the temperature lowers the dark count and minimizes the temperature drift, thus enabling reliable measurements to be made over a wide dynamic range. The driver/amplifier circuit is desirably interfaced to a computer via an I/O board, which preferably also serves as a pulse generator to provide a master clock pulse and a master start pulse, which are required by the linear image sensor. The PDA records the image linearly, not two-dimensionally. Preferably, the data acquired is written directly to the hard disk in real time. Also, preferably, the signals from up to at least 10 elements of the PDA are displayed in real time.
[0037] Preferably, the PDA comprises linearly aligned pixels, in which case each capillary tube is optically coupled to less than about 10 pixels, more preferably from about 7 to about 9 pixels, some of which are coupled to the walls of the capillary and at least one of which is coupled to the lumen of the capillary. A pixel exposed to light produces an electronic signal that is proportional to the intensity of incident light.
[0038] The light source 28 preferably emits light of a wavelength in the range from about 180 nm to about 1500 nm. Examples of a suitable light source 28 include mercury (for ultra violet (UV) light absorption), tungsten (for visible light absorption), iodine (for UV light absorption), zinc (for UV light absorption) cadmium (for UV light absorption), xenon (for UV light absorption) or deuterium (for visible light absorption) lamps. Desirably, the light source 28 emits a wavelength of light that will be absorbed by the species of interest. Which wavelength of light is absorbed by the species of interest can be determined using a standard absorption spectrometer. Alternatively, spectroscopic tables that provide such information are available in the art, such as through the National Institute of Science and Technology. Desirably, a maximally absorbed wavelength of light is selected for a given species to be detected or measured such that smaller amounts of the absorbing species can be detected. The light source 28 can be a point source. Also, preferably, the light source 28 has a power output of about 0.5 mW to about 50 mW.
[0039] An optical filter 36 is desirably positioned between the planar array of capillary tubes 24 and the detector 34 . The optical filter 36 prevents stray light from the outside environment from reaching the detector 34 . The filter 36 passes light at and near the wavelength emitted from the light source 28 and blocks light of other wavelengths.
[0040] A flat-field lens 32 is desirably positioned between the planar array of capillary tubes 24 and the detector 34 . The flat-field lens 32 couples light that is not absorbed by the one or more absorbing species in each sample with the detector 34 . While a lens that is not a flat-field lens can be used in the context of the present invention, it is disadvantageous in as much as it does not image the entire field evenly. Consequently, the edges of the field are distorted and the absorption of the capillary tubes 24 positioned at the edges of the field of the lens cannot be detected or measured. The flat-field lens 32 inverts the image of the planar array onto the face of the detector 34 .
[0041] A collimating lens 30 is desirably positioned between the light source 28 and the planar array of capillary tubes 24 . The collimating lens 16 focuses the light from the light source 28 to irradiate the capillary tubes 24 more effectively.
[0042] While the sample can be introduced into each capillary tube 24 in a planar array of multiple capillary tubes 24 by any suitable method, preferably the samples are introduced into the capillary tubes 24 by pressure, gravity, vacuum, capillary or electrophoretic action.
[0043] The above components are placed to eliminate substantially, and desirably, completely, stray light. There are two kinds of stray light. One kind of stray light is the glare that results from the capillary tubes 24 having sidewalls and interior lumens. The other kind of stray light is that which is due to the presence of other capillary tubes 24 . This kind of stray light is referred to as “cross talk.” Cross talk essentially is the glare from other capillary tubes 24 . Thus, there needs to be sufficient distance between the sample and the flat-field lens 32 to eliminate substantially and, desirably completely the two kinds of glare. The rate of decrease of stray light as the distance increases will eliminate most of the glare from the containers. Glare can be assessed by measuring a totally absorbing material in a container. If there is any light detected, that light is due to glare.
[0044] Preferably, raw data sets are extracted into single-diode electropherograms and analyzed by converting the transmitted light intensities collected at the detector 34 to absorbance values using a capillary tube 24 containing only buffer solution as a continuous blank reference (control). Alternatively, as many as five and preferably three adjacent diodes may be summed for each capillary tube 24 of the array to increase the overall light intensity. Root-mean-squared noise in the electropherograms is obtained using a section of baseline near one of the analyte peaks. Mathematical smoothing can be used to reduce noise significantly, without distorting the signal. In this regard, as high a data acquisition rate as possible should be employed to provide more data points for smoothing. Various algorithms including binomial, boxcar and Savitzky-Golay smoothings are preferred methods of mathematical smoothing.
EXAMPLE 1
Separation of Egg White Proteins
[0045] The starting material was egg white. The starting solution was 25 mM diethanolamine adjusted to pH 9.5 with hydrochloric acid. The egg white was diluted with the starting solution to one fourth initial concentration and centrifuged at 13,400 rpm for 5 minutes. The supernatant was injected into a chromatofocusing column 16 . The column 16 was a Mono P HR 5/20 from Pharmacia Biotech packed with Mono P, an anion exchange resin. The column 16 was equilibrated before sample injection with the starting solution. After sample injection, the column 16 was eluted with a solution 10 of 2 mM N-[2-Hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine (tricine, pK a =8.1), 2 mM 3-(Cyclohexylamino)-2-hydroxy-1-propanesulfonic acid (CAPSO, pK a =9.6), 2 mM 3-(Cyclohexylamino)-1-propanesulfonic acid (CAPS, pK a =10.4), 2 mM Iminodiacetic acid (pK a =2.98), 2 mM Glycine (pK a1 =2.35, pK a2 =9.78), 2 mM 4-Morpholinepropanesulfonic acid (MOPS, pK a =7.2), 2 mM 2-Morpholinoethanesulfonic acid (MES, pK a =6.1), 2 mM tris(hydroxymethyl)aminomethane (Tris, pK a =8.3), 2 mM 2-[(2-Hydroxy-1,1-bis(hydroxymethyl)ethyl)amino]ethanesulfonic acid (TES, pK a =7.4), 2 mM Alanine, 2 mM 4-(2-Hydroxyethyl)piperazine-1-ethanesulfonic acid (HEPES, pK a =7.5), 2 mM N-(2-Hydroxyethyl)piperazine-N′-(3-propanesulfonic acid) (EPPS, pK a =8.0), 2 mM N-(2-Acetamido)-2-aminoethanesulfonic acid (ACES, pK a =6.8), 2 mM N-(1,1-Dimethyl-2-hydroxyethyl)-3-amino-2-hydroxypropanesulfonic acid (AMPSO, pK a =9.0), 2 mM 2-(Cyclohexylamino)ethanesulfonic acid (CHES, pK a =9.3), 2 mM [(2-Hydroxy-1,1-bis(hydroxymethyl)ethyl)amino]-1-propanesulfonic acid (TAPS, pK a =8.4), 2 mM 1,1,1,3,3,3-Hexakis(dimethylamino)diphosphazenium tetrafluoroborate (Bis-Tris) and 2 mM arginine (pK a1 =1.82, pK a2 =8.99), adjusted to pH 3.5 with 10% acetic acid.
[0046] [0046]FIG. 2 shows the output from the chromatofocusing column 16 . The pH of the solution exiting the column and the absorbance (at 280 nm) of any species are monitored as a function of time. Five different fractions were collected, one fraction each for the small absorbance peaks labelled 1, 2 and 3 and two fractions, 4 and 5, for the large absorbance peak.
[0047] The fractions collected from the chromatofocusing instrument were electrokinetically injected into the capillaries 24 of the MCGE system. Separations were performed at 15 kV with a running time of 30 min.
[0048] [0048]FIG. 3 shows electropherograms obtained simultaneously for the five fractions. All electropherograms show further resolution of egg white proteins than was achieved by chromatofocusing alone. For example, what is one protein absorbance peak in fraction 3 is further resolved into one large, one medium and several small peaks, all corresponding to different proteins, in electropherogram 3 .
[0049] From the above description it can be seen that the invention works, provides a valuable separation system and accomplishes the stated objectives. | Disclosed is a two-dimensional protein separation method. It makes separating a protein sample by chromatofocusing into a plurality of aliquots, and then loading each aliquot into a separate capillary tube; and separating each aliquot by multiplexed capillary electrophoresis to produce a two-dimensional array of separated proteins. A preferred integrated buffer for this system is also disclosed. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Continuation application of PCT/IB99/00188 filed Feb. 3, 1999, entitled Device for Sterilizing a Chamber. Priority is claimed to the PCT application filing date under 35 U.S.C. § 365.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for cleaning and sterilizing the inside of a chamber, comprising a supply of sterilizing liquid for this chamber, and means for inducing, within this sterilizing liquid, variations in pressure, amplitude and frequency, and in the gradient of said variations, said means being adapted to generate cavitation within this liquid.
2. Description of Related Art
It has been observed that cavitation, in addition to its familiar undesirable effects in hydraulic systems, such as attack of surfaces, noise, and loss of contact with the liquid, has other characteristics which may prove beneficial in some applications.
The first of these characteristics is mechanical and makes it possible to go beyond the limits of capillarity in a cavitation regime. This property may therefore be of use when treating regions which are otherwise inaccessible.
The destructive properties can be used judiciously by exploiting the thermal wave which, although temporary, is nevertheless substantial. The same is true of the accompanying oxidation reaction. This is because the exothermal implosion of the vapor bubbles created by negative pressure on a microorganism releases its energy in a very short time and on a very small surface area, determining temporarily a very high temperature.
It is therefore the conjunction of mechanical, thermal and even chemical effects which makes it possible at one and the same time to improve the use of a cleaning and/or sterilizing agent and to increase its efficacy. The dissolution of one substance in another is thereby greatly enhanced and permits sterilization of a cavity or of a body immersed in a cavitation regime, which it would not be possible to obtain by simple rinsing or prolonged immersion with the same liquid agent.
As cavitation appears when know thermodynamic conditions in a defined liquid are satisfied, it suffices for the inside of a chamber which is closed and filled with liquid to be subjected to pressure variations which are adequate in their amplitude and form to generate cavitation in this liquid at its particular temperature. The effect of cavitation may be exerted on the liquid itself, on the walls of the container or on any body immersed therein.
The demands of the pressure signal are however very particular and are difficult to obtain solely by mechanical selection of the desired pressure levels and frequency.
The use of cavitation for cleaning and sterilizing has already been the subject of many applications in the medical field, or for cleaning and sterilizing medical or paramedical equipment. The combination of ultrasonic frequencies and of cavitation has also been proposed for cleaning and sterilizing. Reference may be made, by way of example, to DE 39 03 648 which relates to a method for inactivating viruses in a liquid by means of the cavitation generated by varying the flow speeds within the liquid. This method is implemented with the aid of a high-pressure pump and a homogenization valve placed downstream.
In EP 0,078,614, contact lenses are cleaned and disinfected in a saline solution in which cavitation is created at an ultrasonic frequency.
Another method for cleaning and sterilizing which combines ultrasound and cavitation is described in EP 0,595,783 and in U.S. Pat. No. 4,193,818. Cavitation combined with ultrasound has the disadvantage of attacking the cleaned surface.
It has also been proposed, in EP 0,299,919, to use cavitation for devitalizing teeth, an endpiece being fitted in a leaktight manner onto an opening formed to give access to the pulp chamber of the tooth. This endpiece comprises a liquid injector connected to a feed pump and a discharge conduit connected to a suction pump. The suction pump creates bubbles in the liquid, which the pressure pump causes to implode, thereby producing cavitation.
An improvement to the above device has been proposed in EP 0,521,119 in which a water-jet pump is arranged in the adjustable endpiece which can be fitted in a leaktight manner on the orifice of the pulp chamber of the tooth filled with Javel water. The inlet of this water-jet pump is connected to the outlet conduit of a piston pump, its outlet is connected to a discharge conduit, and its suction conduit opens into the pulp chamber. At each cycle of the pump, a reciprocating motion of a certain volume of liquid is produced in the discharge conduit due to the alternating compression and suction, in a conduit connecting the pump to the discharge conduit by way of a water-jet pump, generating alternating negative pressures and overpressures in the liquid of the pulp chamber, thus generating cavitation.
The first of these devices for devitalization requires two pumps and involves a high level of consumption of liquid, consisting of the treatment liquid itself. The second of these devitalization devices uses a single-action piston pump which is as it were the motor driving the water-jet pump, generating variations in pressure in the pulp chamber. The piston pump used for this purpose produces a sinusoidal pressure which, starting from the closure of a single-action valve, increases until it reaches the gradient of the sinusoid. Only the gradient is useful in creating cavitation, and this gradient must be as steep as possible in order to create a variation which is as sudden as possible. Given that the sinusoidal variation does not suffice by itself to cause the desired cavitation, it acts on the pressure of the pulp chamber by way of a body of liquid which it causes to move and works as a resonator to create the required sudden pressure variations by way of the water-jet pump.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to attain required sudden pressure variations, but directly without the aid of a water-jet pump, that is to say without a positive pressure generator. To this end, the subject of the present invention is a device for cleaning and sterilizing the inside of a chamber. By using a switching member it is possible for a column of liquid, connecting this switching member to the sterilization chamber, to be brought into communication with two defined pressure levels, the difference between these corresponding to the desired amplitude, so that the gradient of the variation is very considerable, and only the losses of head in the conduits influence this gradient since the pressures of the two levels are constant. In addition, the pressure of just one of the two pressure levels must be created artificially, while that of the other level, corresponding to the highest pressure, is simply the atmospheric pressure. The system therefore functions as a spring piston which tends constantly to be brought back to one of its two positions by the return spring. In the case of the present invention, the spring is formed by the atmospheric pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
The attached drawings illustrate diagrammatically and by way of example an embodiment of the cleaning and sterilizing device which forms the subject of the present invention.
FIG. 1 is a block diagram showing the principle of the device;
FIG. 2 is a cross-sectional view of a detail from FIG. 1;
FIG. 3 is an elevation view of another detail from FIG. 1;
FIG. 4 is a view along IV—IV in FIG. 3;
FIG. 5 is a view showing the detail from FIG. 3 mounted on a tooth shown in cross section, in accordance with the first use;
FIG. 6 is a view showing the detail from FIG. 3 mounted on a cleaning and sterilizing chamber for contact lenses;
FIG. 7 is an elevation view of an endoscope, part of which is lodged in a sterilizing chamber of the device according to the invention, specifically adapted for this use; and
FIG. 8 is an elevation view, partially in cross section, of another application of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The cleaning device whose operating principle is illustrated by FIG. 1 comprises a treatment chamber 1 connected on the one hand to a calibrated supply of treatment liquid 2 and on the other hand to a distribution or switching member 3 by way of a conduit 4 . A first inlet 5 of this switching member 3 communicates with the atmospheric pressure and a second inlet 6 communicates with a low pressure source 7 connected to a vacuum pump 8 , and to an adjustable auxiliary air inlet 14 . This switching member 3 , which is represented in more detail in FIG. 2, comprises a cylindrical body through which there runs an axial channel into which the conduits 5 and 6 open laterally, and of which one axial end communicates with the conduit 4 connecting this switching member to the treatment chamber 1 .
A distribution rotor 10 is mounted in this axial channel, and an O-ring seal 11 fitted around the rotor at one end of the block 9 and held in place by a lid 12 ensures the leaktightness of the axial channel. The end of the distribution rotor 10 protruding from the block 9 is integral with the drive shaft of a motor 13 . The end of the rotor 10 communicating with the conduit 4 has an axial passage 10 a provided with two slots 10 b and 10 c which are intended to bring the axial passage 10 a cyclically into communication with the conduit 5 and the atmospheric pressure and, respectively, with the conduit 6 and the vacuum source.
The first phase of the cyclical process generated by the device which has just been described involves suddenly lowering the pressure in the treatment chamber 1 to below the vapor pressure of the treatment liquid which fills this chamber 1 , bringing it into communication with the low pressure source 7 , the rotor 10 then being located in the angular position illustrated in FIG. 2 . The temperature, the nature of the liquid and its purity will have an influence on the level and the gradient of the necessary variation. Each impurity or mechanical discontinuity will be a potential bubble interference for a given liquid. It should be noted that in the case of the present invention, this gradient is very steep, and only the losses of head via the conduits come into consideration for establishing the negative pressure in the chamber 1 , by contrast there is no longer the interference of the sinusoidal movement of a pump, as in the solutions of the prior art.
The second phase of this process consists in causing implosion of the vapor bubbles created in the first phase, by re-establishing the atmospheric pressure in the chamber 1 , which is obtained by the rotation of the rotor 10 which brings the slot 10 b into communication with the conduit 5 and the atmospheric pressure. The liquid which had been suctioned in the conduit 4 then returns to the chamber, creating a slight instantaneous overpressure which triggers simultaneous implosion of all the vapor bubbles previously formed.
The maximum effect of the change of state is proportional to the vacuum maintained in the low pressure source 7 by a diaphragm pump 8 . The vacuum level can however be modulated as a function of the desired power by virtue of the adjustable auxiliary air inlet 14 .
The system is filled, by way of the treatment chamber 1 , with the supply of calibrated liquid 2 , the mean pressure being negative in the operating mode. The reciprocating action of the liquid column is in fact provided only for a correctly primed conduit and regeneration of the liquid is desirable even if it opens the system.
The speed of rotation of the motor 13 driving the rotor 10 is adjustable as a function of the nature of the liquid used, its temperature and the chosen negative pressure. The state of the mixture removed from the treatment chamber 1 (proportion of dissolved gas) through the conduit 4 plays a role and may require adaptation, in particular during the operation of dissolution.
The dimensions and the rigidity of the conduit 4 connecting the treatment chamber 1 to the switching member 3 are in relation to the frequency of the cycle. A conduit made of polyurethane and with an internal diameter of 2 mm and a 1-mm wall and length of 320 mm has given good results at a frequency of the order of 15 to 25 Hz with most of the liquids used. This size is suitable for generating a good cavitation regime in volumes of up to several cm 3 . The dimensions of the restriction of the inlet for fresh liquid entail a compromise between good filling of the tubing and the inherent loss of vacuum; a tube made of stainless steel with an internal diameter of 0.3 mm and a length of 15 mm has given good results. The operational output depends on the liquid used and is of the order of 10 m/min.
The calibration of the air inlet 14 depends on the diaphragm pump used. A regulating valve offers the best ease of use. The diaphragm pump must be such as to make it possible to reach, in the low pressure source 7 , a vacuum of at least −0.9.10 5 Pa in the operating regime when the air inlet 14 is completely closed. It should be noted that this pressure is in itself higher than the vapor pressure of the liquid. However, by virtue of the liquid column 4 , it is possible in a dynamic regime to reach peaks lower than the value of the negative pressure in the low pressure source 7 .
FIGS. 3 to 5 illustrate an application of the device which has just been described, in which it is used for devitalizing a tooth. In this particular use, the treatment chamber 1 is formed by the pulp chamber P of the tooth D to be devitalized, an endpiece 15 being intended to connect the pulp chamber P of the tooth D on the one hand to the supply 2 of treatment liquid and on the other hand to the conduit 4 connecting the pulp chamber P to the switching member 3 .
As is shown in FIG. 5, the endpiece 15 comprises a joining element 15 a fitted in a leaktight manner in a flexible connection element 15 b which itself is fitted in an opening formed in the tooth D to permit access to the pulp chamber P of the tooth D. A seal of cement C formed around the flexible connection element 15 b serves to ensure the leaktightness of the treatment chamber. This use offers a real advantage in pulpectomy of vital or nonvital roots. The action of the sodium hypochlorite traditionally used is rendered more effective by an increased interface between the corrosive liquid and the tooth nerve, reaching into the very smallest nooks and corners, which are even inaccessible manually. The sterilizing effect of the cavitation adds to the efficacy of the intervention, eliminating any residual microorganisms. Moreover, the operation is noninvasive, thereby reducing the trauma inflicted.
The use of the supplementary connection element offers a connection which is more ergonomic and which is advantageously flexible. It also has the advantage of allowing the endpiece 15 to be removed and put back in place without having to break the cement C.
FIG. 6 illustrates another advantageous use of the present invention for wetting and sterilizing soft contact lenses. It will be seen in this figure that an endpiece 15 is fixed in an opening giving access to the inside of a treatment chamber 1 ′ in which a soft contact lens L is immersed. The treatment chamber 1 ′ is made up of two parts 1 a′ , 1 b′ which are joined to each other in a leaktight manner, for example by a bayonet-type catch. This hydrophilic contact lens can be freed of all microorganisms by creating cavitation of the volume of liquid in which it is wetted for a duration of the order of 10 min. Immersion, even for the whole night, in the same specific disinfecting product does not by itself achieve the bacterial decontamination deriving from this use.
FIG. 7 illustrates a further advantageous use of the device according to the invention, for endoscopy devices which are not autoclaved, and in particular those which are provided with a channel for biopsy forceps. Such devices are in fact never rendered sterile by simple immersion in the disinfecting liquid to which they are subjected after each use. The cavitation and the circulation of the disinfecting agent in which they are plunged sterilizes them effectively and allows them to be reused after a short time.
The treatment chamber 1 ″ in which the active end of the endoscope E is fitted comprises a tube 16 whose ends are engaged in two annular grooves 17 , 18 , respectively, at the bottom of which there are O-ring seals 19 , 20 , respectively. The annular groove 17 is formed in a closure member 21 , while the groove 18 is formed in a closure ring 22 intended to engage against a frustoconical part 23 of the endoscope E. A joining piece 24 passes through the wall of the tube 16 and is used to connect the inside of the tube to the cavitation generator in FIG. 1 . The inside of the tube 16 which serves as a treatment chamber is fed with treatment liquid via the access channel 25 for the biopsy forceps of the endoscope, when such a channel exists. Otherwise, it can be supplied directly through the wall of the tube 16 .
Another use very similar to that described in FIG. 6 could be applied to the unblocking of catheters. which could be done without removing the catheter. For this purpose, as is illustrated in FIG. 8, the endpiece 15 is fixed to the end of the catheter 26 intended for perfusion. Cavitation will occur as long as the clot blocks the passage, inducing an anticoagulating liquid as far as the interface of the blood clot obstructing the conduit of the catheter 26 . Cavitation will stop spontaneously upon reappearance of a flow of fresh blood being drawn in, evidence of a successful operation, after which perfusion can be reinstated in place of the endpiece 15 .
The use of the device described could also extend to the unblocking of arterial or venous conduits. However, in this case, and given the fact that the walls of these conduits are not rigid, means would be needed to prevent crushing of these conduits, given that in order to create cavitation the pressure has to drop to below the atmospheric pressure.
Of course, the dimensions of the vacuum source 7 and of the switching member will need to be adapted to the volume necessary for the treatment chamber.
Applications other than those previously described, and using the same cleaning and sterilizing device, are of course available. | A device for cleaning and sterilizing the inside of a chamber, including a supply of sterilizing liquid for said chamber and a device for inducing variations in the pressure, amplitude, frequency and the gradient of said variations in the sterilizing liquid, whereby said device is adapted in such a way that cavitation occurs inside the liquid, the device inducing said pressure variations include a liquid column between the chamber and a switching organ, whereby the chamber can be cyclically connected to a depression, whereby the value thereof is related to the amplitude or respectively to the atmospheric pressure. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is generally directed to providing reliable cooling systems for computer systems or for any electronic system requiring cooling. More particularly, the present invention is directed to the cooling of an enhanced test head which contains a very dense electronic package designed for test equipment manufacturers to test both logic and memory packaged products.
2. Prior Art
The test head electronics are required to perform these tasks in the shortest possible time and therefore particularly high heat fluxes are generated in the electronic package. Innovative solutions are necessary to handle these high heat fluxes and still maintain the integrated circuits within temperature specifications.
A typical test head preferably occupies a 15"×30"×30" volume and generates approximately 8,000 watts of heat. This heat flux must be continually removed from this small volume to maintain integrated circuit temperatures at acceptable levels. To convey this heat from the test head an enhanced cold plate mated through conduction cooling to the electronic cards was developed.
A refrigeration system employing a single cold plate which preserves flow isolation between the fluids in the redundant systems. In another aspect of the present invention, there is provided a combination of air and redundant refrigeration cooling for an electronic device such as a mainframe or server processing unit disposed within a cabinet possibly along with other less thermally critical components. In yet another aspect of the present invention, there is provided additional cold plates, each with its own array of electronic circuit cards to be cooled. The entire assembly is mounted on an articulated arm for movement to and from multiple test sites. The enhanced test head is capable of operating continuously in a variety of ambient conditions and under a variety of thermal loads.
In recent years, the semiconductor industry has taken advantage of the fact that CMOS circuits dissipate less power than bipolar circuits. This has permitted more dense packaging and correspondingly faster CMOS circuits. However, almost no matter how fast one wishes to run a given electronic CMOS circuit chip, there is always the possibility of running it faster if the chip is cooled and thermal energy is removed from it during its operation. This is particularly true of computer processor circuit chips and even more particularly true of these chips when disposed within multi-chip modules which generate significant amounts of heat. Because there is a great demand to run these processor modules at higher speeds, the corresponding clock frequencies at which these devices must operate become higher. In this regard, it should be noted that it is known that power generation rises in proportion to the clock frequency. Accordingly, it is seen that the desire for faster computers generates not only demand for computer systems but also generates thermal demands in terms of energy which must be removed for faster, safer and more reliable circuit operation. In this regard, it is to be particularly noted that, in the long run, thermal energy is the single biggest impediment to semiconductor operation integrity.
In addition to the demand for higher and higher processor speeds, there is also a concomitant demand for reliable computer systems and electronics. This means that users are increasingly unwilling to accept down time as a fact of life. This is particularly true in the demanding high pressure environment of electronic test equipment. Reliability in air-cooled systems is relatively easily provided by employing multiple air-moving devices (fans, blowers, etc.). Other arrangements which incorporate a degree of redundancy employ multiple air-moving devices whose speeds can be ramped up in terms of their air delivery capacity if it is detected that there is a failure or need within the system to do so. However, desired chip-operating power levels are nonetheless now approaching the point where air cooling is not the ideal solution for all parts of the system in all circumstances. While it is possible to operate fans and blowers at higher speeds, this is not always desirable for acoustic reasons. Accordingly, the use of direct cooling through the utilization of a refrigerant and a refrigeration system becomes more desirable, especially if faster chip speeds are the goal.
While certain electronic components or modules produce relatively large amounts of thermal energy, it is often the case that these modules are employed in conjunction with other electronic circuit components which also require some degree of cooling but do not operate at temperatures so high as to require direct cooling via a cold plate and/or refrigerant system. If modules of varying thermal energy output are employed in the same system, it is therefore desirable that the cooling systems employed for the lower thermal output modules be cooled in a manner which is compatible with cooling systems employed for the higher temperature modules. To the extent that a degree of cooperation between these systems can be provided, the net result is a system which is even more reliable and dependable. Nonetheless, these dual cooling modalities may be accommodated within a single electronic card assembly.
There are yet other requirements that must be met when designing cooling units for computer systems, especially those which operate continuously and which may in fact be present in a variety of different thermal environments. Since computer systems run continuously, so must their cooling systems unlike a normal household or similar refrigerator which is operated under a so-called bang-bang control philosophy in which the unit is alternating either totally on or totally off. Furthermore, since large computer systems experience, over the course of time, say hours, variations in user load and demand, the amount of heat which must be removed also varies over time. Therefore, a cooling unit or cooling module for a computer system must be able not only to operate continuously but also be able to adjust its cooling capability in response to varying thermal loads.
SUMMARY OF THE INVENTION
In accordance with a preferred embodiment of the present invention, an apparatus for cooling electronic circuits comprises a novel cold plate with a thermal interface to a plurality of conduction plates whereby each conduction plate transfers heat flux to the cold plate from its associated electronic circuit card. Each conduction plate is married to a single electronic card prior to being mounted on the cold plate. The conduction plate/electronic card pairs are then mounted perpendicular to and in parallel fashion onto the cold plate. The heat flux flows from the circuit card to the conduction plate and then into the cold plate. The cold plate has an internal cavity through which cold water is circulated to transfer the absorbed heat flux from the cold plate to a cooling system. The cold plate is shaped in a rectangular manner with a rectangular through-hole centrally located. As the conduction plate/electronic card pair is mounted onto the cold plate, one of the connectors mounted on the electronic card extends through the cold plate through-hole to mate with a matching connector. The cold plate through-hole is one of the essential novel elements that assists in rendering a compact design because it allows the cold plate to be in close proximity to all of the heat sources, i.e., the integrated circuits.
The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings wherein like elements are numbered alike in the several FIGURES:
FIG. 1 is a perspective view of a cold plate illustrating the planar structure with a central through-hole and various mounting holes;
FIG. 2A is a top plan view of the cold plate illustrating a central through-hole, various mounting holes, including the lands for mounting the input and output port;
FIG. 2B is a side elevation view of the cold plate illustrating its planar structure;
FIG. 3 is a bottom plan view of the cold plate without the closing covers illustrating fingers formed on an interior surface of a cavity;
FIG. 4A is a cross sectional view of FIG. 3 taken at AA" illustrating the interior cavity of the cold plate-and the fingers projecting into the cavity;
FIG. 4B is a cross sectional perspective view of FIG. 3 taken at BB" illustrating a first embodiment of the interior cavity of the cold plate and the fingers projecting into the cavity;
FIG. 4C is a cross sectional perspective view of FIG. 3 taken at BB" illustrating a second embodiment the interior cavity of the cold plate and the fingers projecting into the cavity;
FIG. 5A is a side elevation view of a cross-channel end cap which attaches to the cold plate to seal the cross-channel cavity;
FIG. 5B is a top plan view of a cross-channel end cap which attaches to the cold plate to seal the cross-channel cavity;
FIG. 5C is a side elevation view of a cover plate which attaches to the cold plate to seal an interior cavity;
FIG. 5D is a top plan view of a cover plate which attaches to the cold plate to seal an interior cavity;
FIG. 6 is a side elevation view of the cold plate assembly illustrating the electronic card/conduction plate pair mounted on top of the cold plate;
FIG. 7A is a side elevation view of a port housing which mounts on the cold plate to form either an inlet port or an outlet port;
FIG. 7B is a perspective view of FIG. 7A taken at line AA illustrating the opening in which a quick disconnect nipple is mounted;
FIG. 7C is a bottom plan view of a port housing bottom surface which mounts on the cold plate; and
FIG. 7D is a side elevation view of a quick disconnect nipple which mounts in the port housing on the cold plate.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view of a cold plate 2 made from copper illustrating the planar structure with a large central through-hole 3. Input port 8 and output port 9 are mounted on the top surface 20 at a front end 22 of the cold plate 2. Cold water is fed from a cooling system (not shown) to input port 8. The cold water flows in an interior cavity 4 (see FIGS. 3, 4A & 4B) along path A to the rear end 23 of the cold plate 2, crosses over to the opposite side in cross-channel 10 and returns to the output port 9 in a similar interior cavity 4. Thus, any thermal energy transferred to the cold plate 2 is absorbed by the cold water and transported to the cooling system.
The cold plate 2 is mounted to an articulated test head platform (not shown) using the through-holes depicted in rows R 1 , R 3 , R 4 & R 6 The holes depicted in rows R 2 & R 5 are not through-holes but are in fact bottomed within the cold plate 2. These holes, R 2 & R 5 , are used to mount the conduction plate feet 44 as shown later in FIG. 6.
FIG. 2A is a top plan view of the cold plate 2 illustrating a central through-hole 3, various mounting holes 1 1, 12 & 13 and the input and output landings 15 & 16 for mounting the respective input and output ports 8 & 9. The series of through-holes in rows R 3 & R 4 which surround the periphery of central through-hole 3, and the series of through-holes in rows R 1 & R 6 which lie near the periphery of the cold plate 2 are used to mount the cold plate 2 to the test head (not shown). The holes in rows R 2 & R 5 are for mounting conduction plate/electronic card pairs 70 as further described in reference to FIG. 6. There are 38 holes in each row R 2 & R 5 labeled columns C, through C 38 . As can be seen in FIG. 2A, a conduction plate/electronic card pair 70 has been mounted in holes R 2 C 1 , R 2 C 2 , R 5 C 1 , & R 5 C 2 . In this manner nineteen (19) individual conduction plate/electronic pairs 70 can be mounted on each cold plate 2. A test head is usually comprised of four cold plates 2 so that a test head may have up to seventy-six conduction plate/electronic pairs 70 operating simultaneously.
FIG. 2B is a side elevation view of the cold plate illustrating its planar structure with a view of an opening to the cross-channel cavity 10. During manufacture the cross-channel cavity is bored and reamed into the cold plate 2 from the cold plate exterior side wall 19. The cross-channel connects the two interior cavities 4A & 4B to form one continuous cavity 4 throughout the cold plate 2. After the cross-channel cavity 10 has been machined, an appropriately sized end cap (see FIGS. 5A & 5B) seals the opening to the cross-channel cavity 10 on the cold plate exterior side wall 19. Mounting flange 18 extends beyond the exterior side wall 19 (protrudes out of the page) so that mounting bolts passing through mounting holes 13 (see FIG. 2A) can secure the cold plate 2 to the test head (not shown).
Referring to FIG. 3, a bottom plan view of the cold plate 2 is shown. The two interior cavities 4A & 4B with their depending array of fingers 6 are illustrated as the cover plates 14 (see FIG. 4B) are not yet in place. The interior cavities 4A & 4B are machined into the cold plate 2 along two parallel paths, each extending from a respective interior cavity front end 24 & 25 to a respective interior cavity rear end 26 & 27 at a first depth. Next a CNC milling machine cuts deep grooves 50 and/or cross-cuts 52 into each cavity 4A & 4B (see FIGS. 4B & 4C) to define a plurality of fingers 6. However front ends 24 & 25 and rear ends 26 and 27 of the interior cavities 4A & 4B are fingerless. In their respective cavity front ends 24 & 25, through-holes 8A & 8B are bored to form the inlet port 8, and similarly through-holes 9A & 9B are bored to form the outlet port 9. The two cavities 4A & 4B are connected within the cold plate 2 by a cross-channel 10 bored into the plate 2 from a side edge as discussed above. The cold plate fluid path A begins at the inlet through-holes 8A & 8B flowing into the inlet cavity front end 24, continues through the fingers 6 of inlet cavity 4A to rear end 26, traverses the cold plate 2 through the cross-channel 10 to rear end 27, continues along outlet cavity 4B to front end 25, and exits the cold plate 2 at the outlet through-holes 9A & 9B. It
Referring to FIG. 4A, a cross sectional view of FIG. 3 taken at AA" is shown. The fingers 6 are illustrated in the inlet interior cavity 4A and the outlet interior cavity 4B. It should be observed that the fingers 6 are machined into the cold plate 2 so that their base 7 (see FIG. 4B) is connected to that portion of the interior cavity surface 5 which is directly under the cold plate top surface 20. Thus when the conduction plate feet 44 are mounted onto the cold plate top surface 20, there is a very short path of low thermal resistance between the conduction plate feet 44 and the cold plate fingers 6. This assures a very high thermal conductance between the conduction plate and the cold water flowing through the cold plate fingers 6 allowing very efficient heat flow from the integrated circuits to the cooling system.
Referring to FIG. 4B, a first embodiment of a cross sectional perspective view of the cold plate 2 in FIG. 3 taken at BB" is shown with a cover plate 14 in near proximity. Only the first two rows of fingers 6 are shown but it should be noted that the rows of fingers 6 extend completely throughout the inlet cavity 4A and the outlet cavity 4B excepting their respective front ends 24 & 25 and rear ends 26 & 27. Chilled water flows along the interior cavities 4A & 4B in the grooves 50 and cross-cuts 52 absorbing thermal energy from the surface area of each finger 6.
Referring to FIG. 4C, a second embodiment of a cross sectional perspective view of the cold plate 2 in FIG. 3 taken at BB" is shown with a cover plate 14 in near proximity. In this embodiment only longitudinal grooves 50 are cut by the milling machine along the interior cavity 4. Chilled water flows along the interior cavities 4A & 4B in the grooves 50 absorbing thermal energy from the finger sidewalls. Each interior cavity 4A & 4B is sealed by metallurgically bonding cover plates 14 onto shoulders 32 which will form an air-tight cavity from their respective front ends 24 & 25 to their respective rear ends 26 & 27.
Referring to FIG. 5A, a side elevation view of a cross-channel end cap 17 which attaches to the cold plate exterior side wall 19 to seal the cross-channel cavity 10 is shown. The end cap 17 sits in a shoulder circumferentially cut around the opening to the cross-channel cavity 10 on the cold plate side wall 19. The end cap 17 is metallurgically bonded to the shoulder to provide an air-tight seal.
Referring to FIG. 5B, a top plan view of a cross-channel end cap 17 which attaches to the cold plate side wall 19 to seal the cross-channel cavity 10 is shown. The oval shape and dimensions of the end cap 17 match the circumferential shoulder cut into the cold plate side wall 19.
Referring to FIG. 5C, a side elevation view of a cover plate 14 is shown. A first cover plate 14 seals interior cavity 4A while a second cover plate 14 seals interior cavity 4B (see FIG. 3). Each cover plate 14 sits in a respective shoulder 32 circumferentially cut around each opening of interior cavities 4A and 4B on the cold plate bottom surface 21. Each cover plate 14 is metallurgically bonded to its respective shoulder to provide an air-tight seal for its respective cavity 4A and 4B.
Referring to FIG. 5D, a top plan view of a cover plate 14 is shown. The rounded comers and peripheral dimensions of the cover plate 14 match the circumferential shoulder 32 cut into the cold plate bottom surface 19 around each interior cavity 4A and 4B.
Referring to FIG. 6, a side elevation view of a cold plate assembly 80 is shown. An electronic card 60 is mated to its copper conduction plate 40 and the conduction plate 40 is maintained in direct thermal contact with the integrated circuits (not shown) mounted on the electronic card 60. The conduction plate 40 has two feet 44, each of which is bolted to the cold plate 2 such that each foot 44 is mounted directly on top of an interior cavity 4 on the top surface 20 of the cold plate 2. Thermal energy generated by the integrated circuits flows to the conduction plate 40, disperses across the copper plate 40 to either of two heat pipes 46 and then downward to the conduction plate feet 44. The heat flux next flows from the feet 44 into the cold plate fingers 6 where it is transferred to the cold water stream and conducted out to the cooling system. Given that only one conduction plate/electronic card pair 70 is shown in this view, it should be noted that each cold plate 2 mounted on the test head can hold up to nineteen conduction plate/electronic card pairs 70 each.
Each electronic card 60 has a first electrical connector 62 and a second electrical connector 63. The first electrical connector 62 of each card 60 mates with a matching test head connector (not shown) which rises up through the cold plate central through-hole 3. The cold plate through-hole 3 allows the cold plate 2 to enjoy close proximity to the integrated circuits mounted on the electronic card 60 providing a path of high conductance for the thermal energy to be dissipated thus lowering the volume requirement of the test head assembly while increasing the thermal efficiency of the cold plate simultaneously.
Referring to FIG. 7A, a side elevation view of a port housing 53 which mounts on the cold plate 2 to form either an inlet port 8 or an outlet port 9 is shown. The front face 64 of the port housing 53 is preferably angled back 15° to allow the axis 65 of the nipple aperture 54 to also be preferably elevated 15°. This enhances an operator's ability to make and break the cooling conduit connections at the input 8 and output 9 ports.
Referring to FIG. 7B, a perspective view of FIG. 7A taken at line AA illustrating the port housing's front face 64 is shown. The nipple aperture 54 is preferably elevated 15° from horizontal. The port end 58 of the quick disconnect nipple 57 will be pressed into the nipple aperture 54 to form an air-tight fitting.
Referring to FIG. 7C, a bottom plan view of a port housing 53 is shown. A flow port 56 is formed on the bottom surface 55 of the port housing 53 and is in fluid communication with the nipple aperture 54 on the front face 64. When the port housing 53 is mounted on the cold plate input port landing 15 or the output port landing 16, an air-tight fluid path is provided from the nipple aperture 54 to the interior cavities 4A or 4B of the cold plate 2.
Referring to FIG. 7D, a side elevation view of a quick disconnect nipple 57 is shown. The port end 58 is pressed into the nipple aperture 54 of the port housing 53 to provide an air-tight connection. The quick disconnect fitting 59 of the nipple 57 thereafter protrudes at a preferably upward angle of 15° so that input and output coolant conduits may be attached to the cold plate 2.
From the above, it should be appreciated that the systems and apparatus described herein provide a reliable redundant cooling system for computer and other electronic systems. It should also be appreciated that the cooling systems of the present invention permit the operation of computer systems at increased speeds. It should also be appreciated that the objects described above have been filled by the systems and methods shown herein particularly with respect to the utilization of a cold plate having dual flow-wise isolated but thermally coupled passages.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. | A cold plate, planar in shape, is machined to provide an interior cavity having a plurality of thermally conductive members which transfer any thermal energy absorbed by the cold plate to a chilled water stream flowing through the interior cavity. Electronic cards are mechanically and thermally married to copper conduction plates which mount on a surface of the cold plate. The cold plate can hold up to nineteen pairs of conduction plate/electronic card assemblies. Thermal energy generated by the electronic circuit cards flows into the conduction plate and then into the chilled water stream flowing in cold plate. The chilled water is provided by a cooling system as known in the art. The cold plate also provides a large central through-hole through which the electronic cards are electrically connected to a computer system. The cold plate through-hole allows the cold plate to enjoy close proximity to the thermal source providing a path of high conductance for the thermal energy to be dissipated. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a drive transmission means which is attached to a developing unit of an image forming apparatus.
Generally, the developing unit of an electrophotographic image forming apparatus is composed of: a developing unit main body which forms a housing; a first stirring member which stirs toner supplied into the developing unit; a second stirring member which is rotated in the opposite direction to the first stirring member; a supply roller which supplies to a developing sleeve a two component developer in which toner and carrier are fully stirred and mixed by the first and second stirring members; the developing sleeve; a developer thin layer forming means; and a drive transmission mechanism. An electrostatic latent image which is formed on the surface of a photoreceptor adjoining the developing sleeve with a predetermined gap, is given toner conveyed by the developing sleeve so that a toner image can be developed. Rotation of the stirring members, the supply roller and the developing sleeve is transmitted by the drive transmission mechanism section which is attached to a side surface of the developing unit main body.
Conventionally, for example, each stirring member and the supply roller are rotatably supported by bearing sections provided on both side portions in the longitudinal direction of the developing unit main body which forms a housing of the developing unit, and connected with the drive transmission means attached to one side portion of the developing unit main body so that rotation of a drive source can be transmitted.
As described above, when bearing sections of each stirring member and the supply roller are provided on both side portions of the developing unit main body, assembling the stirring members and the supply roller with respect to the developing unit main body is not simple, so that assembly is troublesome.
Further, conventionally, when the developing unit is assembled, the stirring members and the supply roller which are mounted in the developing unit, and the drive transmission member of the drive transmission mechanism are connected so that their mechanical phases match each other, for example.
Problems to Be Solved by the Invention
However, when phases of connecting portions provided respectively on the stirring member, the supply roller and the drive transmission member are matched so that they can be connected with each other, since a working space for the connection is small, and furthermore an operator can not observe the connecting work, it takes a long period of time and the work is troublesome. Furthermore this is a large obstacle to automatic assembly of the developing unit.
The first object of the present invention is to solve the aforementioned problems and to provide a developing unit in which matching of the phase of a rotational member or a swinging member equipped in the developing unit, with that of a drive transmission member of a drive transmission mechanism is not required, and they can be easily connected with each other.
Further, the present invention relates to bearing means of process members which are rotatably supported by process units provided in an electrophotographic image forming apparatus.
Generally, in this type of an electrophotographic image forming apparatus, there are provided process units, that is, a photoreceptor drum unit which is an image carrier, developing units which supply toner onto a electrostatic latent image formed on the surface of the photoreceptor drum and develop it, a fixing unit which thermally fixes a toner image transferred onto a recording sheet, and a cleaning unit which cleans the surface of the photoreceptor drum after the toner image has been transferred. Desired toner images are successively recorded on the surface of the recording sheets by each process unit.
Conventionally, each process member such as the photoreceptor drum, a toner stirring member, a fixing roller, and a cleaning roller, which are mounted on each process unit, is rotatably supported by the bearing section provided on, for example, a frame of an image forming apparatus or both side portions of a casing of the process unit.
Conventionally, a plurality of stirring members mounted in the process unit, that is, the developing unit, are rotatably supported by bearing sections provided on both side portions in the longitudinal direction of the developing unit main body which forms a housing of the developing unit. Seal members are provided on the bearing sections so that toner contained in the developing unit main body can not leak outside.
Accordingly, it takes a long period of time and is inefficient to mount the seal members in bearing sections one by one, or to fit shafts of stirring members into bearing holes of the bearing sections. This is a large obstacle to automatic assembly of the developing unit.
Bearing sections of the photoreceptor drum unit, the fixing unit and the cleaning unit have the same problem as the aforementioned, although seal members are not used therein.
The second object of the present invention is to solve the problem, to eliminate seal members, and further to provide a process unit of the image forming apparatus by which automatic assembling can be conducted efficiently.
SUMMARY OF THE INVENTION
The first object of the present invention is accomplished by a developing unit of an image forming apparatus in which toner is supplied onto an electrostatic latent image formed on the surface of a photoreceptor so that a toner image is developed, the developing unit being characterized in that: shaft members which are equipped in the developing unit to be rotated or swung, are set inside a developing unit main body which forms a housing of the developing unit; drive transmission members of drive transmission means which transmit drive to the shaft members, are extended into the inside of the developing unit main body; and the shaft members and the drive transmission members are connected within the developing unit main body.
The first object of the present invention is accomplished by a developing unit of an image forming apparatus by which toner is supplied onto an electrostatic latent image formed on the surface of a photoreceptor so that the electrostatic latent image is developed, the developing unit being characterized in that: when a rotational member or a swinging member equipped in the developing unit is connected with a drive transmission member which transmits drive to each member, a bar-like connecting member, one end of which is engaged with a drive transmission member of the drive transmission means, and the other end of which protrudes from the drive transmission member, is provided; a plurality of protrusions, which can transmit rotation, are provided on the peripheral surface of the protruded connecting member; a connecting section to be fitted with the connecting member is provided also on a shaft center of the rotational member or the swinging member opposite to a shaft center of the connecting member so that they can be detachably engaged with each other; and thereby they are connected so that drive can be transmitted.
The first object of the present invention is accomplished by a developing unit of an image forming apparatus in which toner is supplied onto an electrostatic latent image formed on the surface of a photoreceptor to develop it, the developing unit being characterized in that: a drive transmission means which is connected with a rotational member or a swinging member equipped in the developing unit so that drive can be transmitted, is structured in the manner that each drive transmission member of the drive transmission means is equipped in a casing of the drive transmission means formed by a plurality of supporting base materials in order to be structured into a unit.
The second object of the present invention is accomplished by a process unit of an image forming apparatus in which process units such as a photoreceptor, a developing unit, a fixing unit, and a cleaning unit are provided, the process unit of the image forming apparatus being characterized in that: bearing means of each process member such as a photoreceptor drum, a stirring member of the developing unit, a cleaning roller, and a fixing roller, which are rotatably supported by the process units, is provided in the process unit; and the bearing means is separated into upward and downward directions which cross at right angles with respect to the center of a supporting shaft by which the process member is supported.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view showing a condition in which each shaft member is connected with a drive transmission mechanism section in a developing unit main body of an embodiment of the present invention.
FIG. 2 is a side sectional view showing a structure of the drive transmission mechanism section of the embodiment of the present invention.
FIG. 3 is a plan view showing a shape of a base plate of a drive section of the embodiment of the present invention.
FIG. 4 is a plan view showing a shape of a side plate of the drive section of the embodiment of the present invention.
FIG. 5 is a side view showing a shape of a connecting member of the embodiment of the present invention.
FIG. 6 is a plan view of FIG. 5.
FIG. 7 is a perspective view showing a structure of a bearing means of a stirring member equipped in the developing unit.
FIG. 8 is a side sectional view showing another embodiment of the aforementioned bearing means.
FIG. 9 is a front view of the aforementioned bearing means.
FIG. 10 is a side sectional view showing a structure of the developing unit.
FIG. 11 is a view showing an outline of a structure of an image forming apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention will be explained as follows by referring to FIG. 1, a plan view showing a condition in which each shaft member is connected with a drive transmission mechanism section in a developing unit main body, FIG. 2, a side sectional view showing a structure of the drive transmission mechanism section, and FIG. 10, a side sectional view showing a structure of a developing unit.
However, the present invention is not limited to the embodiment.
FIG. 10 is a sectional view showing a principal section of a developing unit 1, and in the drawing, numeral 16 is a photoreceptor drum, numeral 2 is a developing unit main body, numeral 3 is a developing sleeve, numeral 5 is an upper cover, numeral 7 is a first stirring member, numeral 8 is a second stirring member, numeral 9 is a supply roller and numeral 11 is a scraper.
Toner supplied into the developing unit 1 is fully stirred and mixed with a carrier by a first stirring member 7 which is rotated in the arrowed direction and a second stirring member 8 which is rotated in the opposite direction to the first stirring member, and is fed as developer D to the developing sleeve 3 through the feed roller 9.
The first stirring member 7 and the second stirring member 8 are screw-like members which are rotated respectively in arrowed directions opposite to each other and have a spiral wound in a counterclockwise direction. Toner and carrier conveyed to the furthest side by the thrust of the second stirring member 8 are conveyed over a partition plate for stirring, whose upper end is inclined to be lower than the horizontal surface in the furthest side direction of the drawing, to the first stirring member 7, and conveyed to the nearest side of the drawing. Developer D which is charged by means of triboelectric charging caused by a mixing action of toner and carrier is caused to be homogeneous during the aforementioned conveyance, and adheres to the peripheral surface of the developing sleeve 3 in a layer by the supply roller 9 which is formed like a sponge and rotated in an arrowed direction.
The toner conveyed by the developing sleeve 3 is supplied onto the electrostatic latent image formed on the surface of the photoreceptor drum 16 which is separated from the surface of the developing sleeve 3 with a predetermined gap, and the toner image is developed. Rotations of stirring members 7 and 8, the supply roller 9, and the developing sleeve 3 are transmitted respectively by the drive transmission mechanism mounted on the side portion of the developing unit main body 2.
The present invention removes the aforementioned problems, and a connection method of the shaft member, which is equipped in the developing unit 1 and rotated or swung, with the drive transmission member of the drive transmission mechanism section is structured as follows.
A connection method of the stirring members 7 and 8, and the supply roller 9 with the drive transmission member will be explained as an example in the embodiment of the present invention as follows.
As shown in FIG. 1, the developing unit main body is a rectangular housing composed of: an upper surface which is opened in order to accommodate the stirring members 7 and 8, the supply roller 9, and the developing sleeve 3 to be assembled therein; a side surface in which a peripheral surface of the sleeve 3 side is opened; and a base surface section 2a. The length in the longitudinal direction of the developing unit main body 2 is the length in which the developing sleeve 3 can be accommodated, wherein the length of the developing sleeve 3 corresponds to that in the specification of the image forming apparatus in which a sheet of A4 size, for example, can be fed in the manner that the longitudinal direction of the sheet is in the same direction as that of the developing unit. An upper cover (shown in FIG. 10) is mounted on the upper surface of the developing unit main body 2 after the aforementioned members have been assembled, so that the housing can be hermetically structured except the side surface on the developing sleeve 3 side. A unit of the drive transmission mechanism section 20 is mounted on a right side surface 2b in the longitudinal direction of the developing unit main body 2.
The developing unit main body 2 is a molded member made of a synthetic resin material. A rectangular slot 2e is provided from the base surface 2a to the upper surfaces of both side surfaces in the lateral direction with a predetermined depth near the left side surface 2c inside the developing unit main body 2 as shown in FIG. 1, wherein a bearing section 6, which will be explained later, which supports supporting shafts 8d, 7d on the left side of the second stirring member 8 and the first stirring member 7, is inserted into the rectangular slot 2e.
As shown in FIG. 2, the drive transmission mechanism section 20 is composed of the following units, in order from the top of the drawing to the bottom thereof: a driving section base plate 21 and driving section side plate 22 of which a driving section main body 20a is composed; a second stirring member transmission shaft 8a; a first gear 23 which is provided to the shaft 8a; a first stirring member transmission shaft 7a; a second gear 24 which is provided to the shaft 7a; a roller 28 which is rotatably provided to the first stirring member transmission shaft 7a; a supply roller transmission shaft 9a; a second gear 25 for a belt which is provided to the shaft 9a; a third gear 27 for the belt which is provided to the developing sleeve 3 and integrally rotated therewith; a first gear 23a for the belt which is integrally provided to the first gear 23; and an endless timing belt 26 which is wound around the second gear 25 for the belt and the third gear 27 for the belt. As shown in FIG. 3, the drive unit base plate 21 is a synthetic resin molding member which has an external form of almost the same size as a periphery of the side surface portion of the developing unit main body 2 provided with the upper cover 5. Further, as shown in FIG. 2 and FIG. 3, a pole 21d which is raised from a right upper end portion of a base 21h, and a pole 21e which is raised from an almost central portion of a left side end portion are provided on the drive unit base plate 21 in the manner that the poles 21d and 21e have respectively proper thickness and width which can bear stress without any trouble when the drive transmission mechanism 20 is driven.
The right side end surface shown in FIG. 2 from which the poles 21d and 21e rise is a surface to which the drive unit side plate 22 is provided. From the upper side of the drawing, a bearing boss 21a for the second stirring member transmission shaft 8a and a bearing hole 8b, a bearing boss 21b for the first stirring member transmission shaft 7a and a bearing hole 7b, a bearing boss 21c for the supply roller transmission shaft 9a and a bearing hole 9b, a play 27a for a developing sleeve shaft 3a and a mount 21f of the third gear 27 for the belt are provided respectively on the positions corresponding to the stirring members 8, 7, the supply roller 9 and the developing sleeve 3 at the almost central portion in the lateral direction of the base 21h. The bearing bosses 21a, 21b and 21c are each protrusively provided at a predetermined height along the poles, 21d and 21e, and the bearing holes 8b, 7b, and 9b are each provided through the bearing bosses 21a, 21b, and 21c. The right side end surface of the bearing bosses 21a, 21b, and 21c shown in FIG. 2 is a position determination surface and a slidable contact surface of the gears 23, 25 and the roller 28. The poles 21d, 21e, the bearing bosses 21a, 21b, 21c, the bearing holes 8b, 7b, 9b, the play for the developing sleeve shaft 3a, the mount 21f of the third gear 27 for the belt, ribs reinforced as necessary and plays which are not shown in the drawing, are integrally and simultaneously formed when molding the drive unit base plate 21.
The drive unit side plate 22 is a molded member made of a synthetic resin in which the side plate 22 has almost the same outer shape as that of the drive unit base plate 21 and is made of the same material.
As shown in FIG. 2 and FIG. 4, a bearing boss 22a for the second stirring member transmission shaft 8a which is protruded at a predetermined height on both the surfaces of the driving unit side plate 22, and a bearing hole 8c which passes through the bearing boss 22a are provided on the position facing the bearing boss 21a and the bearing hole 8b, provided on the driving unit base plate 21, on the driving unit side plate 22. From the upper side of the drawing to the lower side, a bearing boss 22b for the first stirring member transmission shaft 7a which is protruded at the predetermined height on both the surface of the driving unit side plate 22, and a bearing hole 7c which passes through the boss 22b, and a bearing boss 22c for the supply roller transmission shaft 9a, and a bearing hole 9c which passes through the boss 22c, are provided on the position facing the bosses 21b, 21c and bearing holes 7c, 9c provided on the driving unit base plate 21. Further, at a lower position of the drawing, a play 27a for the third gear 27 for the belt which is engaged with the developing sleeve shaft 3a, and a play 27b which is coaxially provided with the play 27a, are provided. The bearing bosses 22a, 22b, 22c, and the bearing holes 8c, 7c, 9c, the plays 27a, 27b, and reinforcement ribs and plays, which are provided as necessary and not shown in the drawing, are integrally and simultaneously formed when molding the drive unit side plate 22. When the driving unit side plate 22 is integrally mounted by screws or the like on the right side end surfaces of the poles 21d, and 21e provided on the drive unit base plate 21, then the drive unit main body 20a is structured. When the drive unit side plate 22 is mounted on the drive unit base plate 21, central axes of bearing holes 8b, 7b, 9b and 8c, 7c, 9c, which face each other, are aligned correctly. Further, the distance between the surface of the bearing boss 21a of the drive unit base plate 21 and the surface of the bearing boss 22a of the drive unit side plate 22, which face each other, is set a little longer than the longitudinal length of the first gear 23, the first gear 23 is integrally engaged with the second stirring member transmission shaft 8a supported by the bearing holes 8b, and 8c, and rotatably provided between the bosses 21a, and 22a, and the second stirring member transmission shaft 8a is positioned in the axial direction. In the same manner as described above, the second gear 24 is integrally engaged with the first stirring member transmission shaft 7a, which is supported by the bearing holes 7b, and 7c, between the surface 21b and the surface 22b of the bearing bosses, which face each other, and on its left side, the roller 28 is rotatably provided.
The second gear 25 for the belt is integrally engaged with the supply roller transmission shaft 9a which is supported by the bearing holes 9b and 9c between the bearing bosses 21c and 22c. The rotation of the stirring member transmission shaft 8a is transmitted by the first gear 23 which is engaged with a drive source (not shown in the drawing).
The third gear 27 is inserted into the play 27a provided lower than the second gear, and the developing sleeve shaft 3a is engaged into a bearing hole provided corresponding to the center of axis of the third gear 27, and a hole having a sectional shape D, which is provided in the bearing hole of the third gear 27 and not shown in the drawing, is engaged with a shaft having a sectional shape D, which is provided on the developing sleeve shaft 3a and not shown in the drawing, and thus the driving force is transmitted.
The endless timing belt 26 which has been inserted previously when the drive unit base plate 21 and the drive unit side plate 22 were assembled, is wound around the first gear 23a for the belt, the second gear 25 for the belt and the third gear 27 for the belt, and thus the driving force is transmitted to the supply roller transmission shaft 9a and the developing sleeve 3 through the first gear 23 which is engaged with the drive source to be rotated. The rotation of the first stirring member transmission shaft 7a is transmitted by the second gear 24 which is directly engaged with the first gear 23. The roller 28 acts on an upper side (FIG. 2) of the endless timing belt 26 which is wound around the gears 23a, 25 and 27 for the belt so that the belt can be tightly stretched downward and the rotation can be transmitted efficiently.
Cut-out portions for rotation transmission into which couplings 10 are inserted, are provided on the center of axes of the stirring member transmission shafts 7a, 8a, and the supply roller transmission shaft 9a which are projected from the left side surface of the drive unit base plate 21, wherein the couplings 10 will be explained later.
The coupling 10 is a round bar like molded member made of synthetic resin material such as Delrin or Duracon as shown in FIGS. 5 and 6, and on the right side with respect to a flange 10e, a horizontal straight slit 10c is provided ranging from the central portion of an engagement portion 10b to be engaged with holes which are provided on the center of axes of stirring member transmission shafts 7a, 8a, and the supply roller transmission shaft 9a to the right end, and an inclined surface is provided on the peripheral surface on the right end so that the couplings can be easily inserted into holes of the transmission shafts 7a, 8a, and 9a, and tightly engaged with the holes by the elastic force of the engagement portion 10b having the slit 10c when the couplings are engaged with the holes of transmission shafts 7a, 8a, and 9a.
A shaft diameter of the end portion of the engagement portion 10b, on which the slit 10c is provided, is a little larger than a diameter of holes, as shown in the drawing, which are provided on the transmission shafts 7a, 8a, and 9a so that the end portion can not easily slip away from the hole.
As shown in the drawing, a protruded portion is raised from a part of the peripheral surface of the engagement portion 10b to the peripheral surface on the right side of the flange 10e, wherein the height of the protruded portion is the same as that of the peripheral surface of the flange 10e. The protruded portion 10d is engaged with the cut-out portion (not shown in the drawing) provided on each of the transmission shafts 7a, 8a, 9a, and the right side end surface of the flange 10e is engaged with the left side end surface of each of the transmission shafts 7a, 8a, 9a in the manner that the right side end surface of the flange 10e comes into contact with the left side end surface of each transmission shaft, and thereby each coupling 10 can be integrally rotated with each of the transmission shafts 7a, 8a and 9a.
As shown in FIGS. 5 and 6, a connection portion 10a is provided on the left side of each flange 10e so that it can be connected with each of the stirring members 7, 8 and the supply roller 9. Star-shaped teeth 10f having, for example, 10 equal parts, are provided on the connection portion 10a, and an appropriate inclined surface is provided on the peripheral surface of its left end portion.
An angle of the star-shaped teeth is 90°, and the height of the teeth is set to 0.2 mm. The coupling 10 is detachably engaged with each of the transmission shafts 7a, 8a, and 9a at the last step of assembling the drive transmission mechanism section 20.
As shown in FIG. 1, shafts 7d and 8d provided on both sides of the stirring members 7 and 8, are placed on a mount 4 provided near the right side surface portion 2b in the developing unit main body 2, and supported by the bearing portion 6 provided near the left side surface portion 2c. The stirring members 7 and 8 are positioned to be mounted in the manner that right side end surfaces of shafts 7d and 8d are positioned between the mount 4 and an inner wall surface of the right side surface portion 2b, and left side end surfaces of the shafts 7d and 8d are positioned between the bearing section 6 and an inner wall surface of the left side surface portion 2c.
Two U-shaped slots 4a, 4b, which are opened upwardly, are provided on the mount 4 at a predetermined distance therebetween, and the shafts 7d and 8d of the stirring members 7 and 8 are inserted into the slot from the upper side of the developing unit main body 2. The bearing section 6 is composed of bearing plates which are divided into two portions towards the upper and lower sides with respect to the developing unit main body 2, as will be described later in FIG. 7, and the shafts 7d and 8d are rotatably supported in the following manner: semi-circular recesses are provided respectively on the facing surfaces of the bearing plates at a predetermined distance; and the bearing plate 6 is inserted along the slot 2e of the developing unit main body 2, and the recesses face each other. The bearing section 6 which is divided into two is limited to move upwardly by the lower surface of the upper cover 5 to be mounted in a predetermined position of the upper surface of the developing unit main body 2. As described above, the stirring members 7 and 8 are mounted on the developing unit main body 2 in the manner that the stirring members are dropped together with the bearing section 6 from the upper side of developing unit main body 2.
Shafts 9d provided on both sides of the supply roller 9 are inserted from the upper side of the developing unit main body to U-shaped bearing mounts which are formed on inner wall surfaces of both the side surface portions 2b and 2c and are opened upwardly so that the shafts 9d can be positioned to be mounted. Upward movement of the supply roller 9 is limited, for example, by a support plate of the scraper 11 which is fixedly positioned on the upper surface of the bearing mount so that the supply roller 9 can be rotatably supported. Star-shaped connection holes, the shape of which are the same as that of the connection portion 10a, and with which the connection portions 10a of the couplings 10 are engaged, are provided on the center of axes of end portions of right side shafts 7d, 8d of the stirring members 7, 8 and the right side shaft 9d of the supply roller 9, shown in FIG. 1, with a predetermined depth from the end surfaces of the right side shafts 7 d, 8d, and 9d. The star-shaped connection portion 10a is integrally engaged with the star-shaped connection hole in the following manner: the drive transmission mechanism section 20 structured as described above, is mounted on a predetermined position of the right side surface portion 2b of the developing unit main body 2; and thereby the connection portions 10a of the couplings 10 engaged with transmission shafts 7a, 8a, and 9a, are inserted into the connection holes of the stirring members 7, 8 and the supply roller 9 which are positioned near the right side surface portion 2b inside the developing unit main body 2, through bearing holes provided on the right side surface portion 2b.
At the same time, the transmission shafts 7a, 8a, and 9a are axially supported respectively by bearing holes provided on the right side surface portion 2b.
The center of axes of the stirring members 7, 8 and the supply roller 9 are correctly aligned previously with the bearing holes for the transmission shafts 7a, 8a and 9a provided on the right side surface portion 2b.
Accordingly, the drive transmission mechanism section 20 is set on a predetermined position of the developing unit main body 2 from the right side of the developing unit main body 2, and thereby the transmission shafts 7a, 8a and 9a can be engaged with the stirring members 7, 8 and the supply roller 9 through couplings 10 by only engaging their star-shaped teeth simply with each other, so that they are connected easily and surely inside the developing unit main body 2, and therefore, automatic assembling of the developing unit 1 can be conducted easily.
The developing sleeve 3, as described above, is axially supported by the third gear 27 for the belt at the same time as the connection of the stirring members 7, 8 and the supply roller 9 with the drive transmission shafts 7a, 8a and 9a.
An embodiment of the present invention has been described with respect to a connection method of the stirring members 7, 8 and the supply roller 9 with the transmission shafts 7a, 8a and 9a. However, with respect to a rotation member or a swinging member provided in the developing unit 1, they can also be connected inside the developing unit main body 2 using a similar member to the coupling 10, which is of course within the range of the present invention.
In the present invention, shaft members are connected with the drive transmission mechanism section inside the developing unit main body, and therefore they can be mounted respectively in the developing unit main body from simple directions, so that the developing unit can be automatically structured efficiently.
Even when a working space for the connection is small, and when an operator can not observe the connecting work, since a plurality of drive transmission shafts of the drive transmission mechanism section can be connected with a plurality of rotation members or swinging members from one direction simultaneously with a simple operation, the developing unit can be automatically assembled efficiently.
When the developing unit is assembled, the drive transmission means, which is formed into a unit, according to the present invention can be connected with the rotation members or the swinging members, which are mounted in the developing unit, from one direction with a simple operation, and thereby the developing unit can be automatically assembled efficiently.
Next, an embodiment by which the second object of the present invention can be accomplished will be explained by making bearing members of a plurality of stirring members an example. As shown in FIG. 1, square slots 2e into which a bearing plate 6 supporting left side shafts 8d, 7d of the second stirring member 8 and the first stirring member 7 is inserted, are provided on both side surface portions in the lateral direction of the developing unit main body 2 ranging from a bottom portion to a upper surface with a predetermined slot width and length. As shown in FIG. 7, the bearing plate 6 is divided into a lower bearing plate 6a and an upper bearing plate 6b, the shape of which are common, structured by a pair of plates, and formed by plate-shaped molding members made of synthetic resin material.
Semi-circular recesses 6c which are provided for supporting the lower half peripheral surfaces of the left side shafts 7d, 8d of the stirring members 7, and 8, are placed on the lower bearing plate 6a at a predetermined distance in the lateral direction. The upper bearing plate 6b serves as bearings for the upper half peripheral surfaces of the left side shafts 7d, and 8d. Accordingly, when recesses of the upper and lower bearing plates 6b and 6a face each other, bearing holes by which the left side shafts 7d, and 8d are rotatably supported, are formed.
Although not shown in the drawing, right side shafts of the stirring members 7 and 8 are positioned in the manner that the shafts are dropped from the upper side into bearing portions of mounts provided near the right side surface portion inside the developing unit main body 2. End surfaces of the right side shafts are positioned in the developing unit main body 2.
The stirring members 7, and 8 are mounted in the developing unit main body 2 in the following manner: the lower bearing plate 6a is inserted into the slot 2e from the upper side in the arrowed direction while the recess 6c is maintained upward; the left side shafts 7d, 8d of the stirring members 7 and 8 are engaged with the recesses 6c of the lower bearing plate 6a from the upper side; and at the same time, the right side shafts are engaged with predetermined positions of the mounts so that the shafts can be positioned in the developing unit main body.
When the upper cover 5 is integrally mounted on a predetermined position on the upper surface of the developing unit main body 2 after the upper bearing plate 6b is inserted along the slot 2e from the arrowed direction and placed on the upper surface of the lower bearing plate 6a, upward movement of the upper and lower bearing plates 6b, 6a is limited by the lower surface of the upper cover 5. The left side shafts 7d, and 8d of the stirring members 7, and 8 are rotatably supported by bearing holes formed by recesses 6c of the upper and lower bearing plates 6b, and 6a, at a predetermined distance.
Due to the aforementioned, when the bearing plate 6 is provided in the developing main body 2, a seal member to prevent toner from leaking which is provided conventionally in the bearing portion of the left side shafts 7d, and 8d, is not necessary. At the same time, when the stirring members 7 and 8 are assembled, the assembling work can be conducted simply from one direction since the lower bearing plate 6a, the stirring members 7, 8, the upper bearing plate 6b, and the upper cover 5 are successively dropped from the upper side of the developing unit main body 2, so that automatic assembly can be conducted easily.
Next, another embodiment of a bearing means of the stirring members 7 and 8 will be explained as follows.
As shown in FIGS. 8 and 9, a bearing mount 2d which is equivalent to the outer shape of the lower bearing plate 6a is integrally raised from the bottom surface portion 2a of the developing unit main body 2. On the upper surface of the bearing mount 2d, two U-shaped bearing slots 2f with which the left side shafts 7d, and 8d of the stirring members 7, and 8 are engaged, are provided at a predetermined distance.
Dimensions of the U-shaped bearing slots 2f from the bottom of the slots to the upper surface of the bearing mount 2d are set to be slightly larger than the diameter of the left side shafts 7d and 8d.
The bearing mount 2d is integrally molded in the process of molding the developing unit main body 2.
A protruded member 5a is provided on the position which faces the bearing mount 2d on the lower surface of the upper cover 5, and when the upper cover 5 is mounted on a predetermined position on the developing unit main body 2, the lower surface of the protruded member 5a comes into contact with the upper surface of the bearing mount 2d. The left side shafts 7d and 8d of the stirring members 7 and 8 are successively dropped into the bearing slots 2f in the arrowed direction as shown in FIGS. 8 and 9, and then the upper cover 5 is mounted on the developing unit main body 2.
In the manner described above, upward movement of the left side shafts 7d and 8d of the stirring members 7 and 8 which are engaged with the bearing slots 2f, is limited by the lower surface of the protruded member 5a, and the left side shafts 7d and 8d are rotatably supported in the bearing slots 2f.
In the same manner as the aforementioned example, in another example, which is shown in FIGS. 8 and 9, and is structured as described above, a bearing portion is provided in the developing unit main body 2 and the bearing portion is divided into upper and lower directions crossing at right angles with respect to center lines of the left side shafts 7d, and 8d of the stirring members 7 and 8, and thereby the same effects as the aforementioned example shown in FIG. 7 can be obtained.
The present invention is not limited to the above-described examples.
As shown in FIG. 11, the electrophotographic image forming apparatus 10 is at least composed of the following process units: the photoreceptor drum 16 which is an image carrier and rotated endlessly; the developing unit 1 by which toner is given to the electrostatic latent image formed on the photoreceptor 16 surface to develop the latent image; the transfer electrode 13 which transfers the toner image onto the surface of the recording sheet 12 conveyed to the lower side of the peripheral surface of the photoreceptor 14; the discharger 16; the fixing unit 15 by which the toner image transferred onto the recording sheet 12 is fixed; and the cleaning unit 17 by which toner or paper powder remaining on the photoreceptor 16 surface after the toner image has been transferred onto the recording sheet 12, is removed.
By means of the above-described process units noted by numerals 1, 13, 14, 15, 16 and 17, predetermined toner images are successively recorded on the surfaces of the recording sheets 12 which are intermittently conveyed on a predetermined conveyance path.
The bearing means of the present invention can be applied to bearing means by which the photoreceptor drum 16, the stirring members of the developing unit 1, the fixing roller of the fixing unit 15, the cleaning roller of the cleaning unit 17, which are provided to the image forming apparatus 10, are supported.
Examples of the present invention were explained with regard to the bearing means of the stirring members 7 and 8 of the developing unit 1, however it is a matter of course that the divided bearing means, which is obtained by the same method as the aforementioned, can be applied to the bearing portion by which the photoreceptor drum 16, the fixing roller of the fixing unit 15, and the cleaning roller of the cleaning unit 17 are supported.
By means of the bearing means according to the present invention, automatic assembly of process units such as the photoreceptor drum, developing unit, and cleaning unit, which are provided to the image forming apparatus, can be conducted easily, and seal members to prevent toner from leaking which are provided to the bearing portion of the developing unit can be eliminated. | A developing apparatus for use with a photoreceptor to form a toner image, including a housing to store toner therein; an agitator having a shaft whose length is smaller than the inside dimension of the housing; a gear mechanism to transmit a driving force to the shaft member; and a coupling to couple the gear and the shaft, wherein the coupling is positioned inside the housing. | 8 |
RELATED U.S. PATENT DOCUMENTS
[0001] This patent application is an original patent application in the United States. No federal funding was used in the development of this invention.
DESCRIPTION
Summary of the Invention
[0002] The present invention provides a stuffing box having an improved design of a pressure active seal assembly consisting of pairwise arrangements of hollow cones, which adds unexpected long life to the seals thereof.
BACKGROUND OF THE INVENTION
[0003] Standard oil pumping units, also known as pumpjacks, have several components that are essential for operation. One such unit is the polished rod, which is visible from the exterior of the unit. The polished rod moves up and down in a vertical plane, when the unit is in operation.
[0004] The polished rod moves through a stuffing box, which contain seals that lubricate the polished rod, and yet seal the unit to prevent oil leaks. These seals are often constructed of graphite or other soft, malleable material, in order to closely conform to the motions of the polished rod.
[0005] The difficulty with graphite seals, or seals of other soft material, is that they are not durable. Seals must be replaced frequently, at high replacement cost, due to manpower needs, replacement materials, and down time of the pumping unit. Yet, prior to the present invention, it was difficult to engineer hard materials to produce seals of long life and duration.
[0006] A primary object of this invention is the provision of an improved stuffing box for a unit, or the like, having a seal assembly mounted within a main body thereof. There is a seal pack included within the seal assembly which is supported within a seal holder therefor. The seal assembly includes a series of pairwise mounted metal hollow conical seals, so configured to fit tightly around the polished rod.
[0007] Another object of this invention is the provision of slots in the cones, which allow for expansion and contraction of the cones, according to ambient temperature and pressure conditions. This allows the cones to maintain their function of sealing the rod.
[0008] Another object of this invention is to provide a sealing mechanism for a polished rod, which mechanism is comprised of hardened steel or other hard material.
[0009] A significant object of the current invention is to provide a sealing mechanism for an oil producing unit that is significantly more durable than current devices of the same service. Thus, an important objective is to provide more time between replacement services for seals in an oil pumping unit.
[0010] The above objects are attained in accordance with the present invention by the provision of a combination of elements which are fabricated in a manner substantially as described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
[0012] FIG. 1 is a longitudinal side view of the current invention, with partial translucency of the outer surface in order to indicate the presence of interior components.
[0013] FIG. 2 is a longitudinal side view of the current invention, with the head cap removed.
[0014] FIG. 3 is a longitudinal, cross-sectional, side view of the current invention, with interior components displayed.
[0015] FIG. 4 is a side view of a single truncated annular hollow cone of the current invention.
[0016] FIG. 5 is a cross-sectional, view form below of the base of a single truncated annular hollow cone of the current invention.
[0017] FIG. 6 is a side view illustrating details of a single truncated annular hollow cone of the current invention.
[0018] FIG. 7 is a perspective lower side view illustrating details of a single truncated annular hollow cone of the current invention.
[0019] FIG. 8 is a side view of the cap of the housing cylinder of the current invention.
[0020] FIG. 9 is a side view of the base element of the housing cylinder of the current invention.
[0021] FIG. 10 is a view of a pumping unit, or ‘pumpjack’, embodying the current invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
[0023] FIG. 1 discloses the overall structure of the novel packless stuffing box 100 of the current invention. The ‘box’ is actually a cylindrical tube, with sealing elements inside the tube.
[0024] The main body of the outer tube 200 has upper and lower end caps, 20 and 40 , respectively. The entire unit is designed to fit snugly around a polished rod, at the lower end thereof, near the borehole exit.
[0025] A schematic depiction of stuffing box 100 is shown in FIG. 2 . The hollow nature of the tube 200 is emphasized in this depiction.
[0026] FIG. 3 reveals more details of the current invention 100 . The head 20 is shown at the bottom, with exit ports 25 to vent gases. Interior to the main body are pairs of annular seals 50 , in the form of truncated cones. The cones fit pairwise, base-to-base in each pair. Pairs meet other pairs at top-to-top junctures 70 . Optionally, O-rings or other sealant aid may be used at these junctions 70 to ensure a tight seal.
[0027] When assembled, the cones and main body form a channel 80 into which will fit a polished rod of a pumpjack unit. The rod can move up and down in a vertical plane, or can rotate around its long axis. The present invention will maintain a tight seal and prevent the escape of oil.
[0028] An annular seal cone 50 of the preferred embodiment of the current invention is shown in FIG. 4 . The cone is hollow, and open at both its top and its base. Preferably the cone is constructed of steel. The cone also has a through slot 54 , and a recessed base 56 . The slot allows for expansion and contraction as temperatures and pressures increase and decrease. The recessed base allows for tight coupling with another seal cone, to form the pairs shown in FIG. 3 . The hollow area inside the cone is designed to accommodate the shaft of the polished rod in a pumpjack unit.
[0029] FIG. 4 portrays one of the paired metal sealing cones 50 in a perspective view from the side. The cone is truncated at the top, and open at both top and bottom, and is hollow. Preferably the cone is constructed of ⅛ inch carbon steel. The cone has a through slot 54 extending vertically from the top to the bottom of the cone. This allows for thermal expansion of the ring without damaging the walls of the cone. Other slots (no shown in FIG. 4 ) are desirable, but must not be through slots, in order to preserve the integrity of cone 50 . Also present on the cone 50 is a channel 56 that runs along the lower edge of the cone, at the base. This channel allows for close fitting of two paired cones 50 , base to base.
[0030] FIGS. 5 and 6 display the sealing cone 50 from alternate view angles. FIG. 5 shows a preferred embodiment of cone 50 , viewed from its base. From this vantage point, through slot 54 and partial slots 58 are clearly seen. The slots are optimally placed at 120-degree intervals around the circumference of the cone. The dashed line 59 represents the wall of the cone 50 rising behind the base in this view.
[0031] Turning now to FIG. 6 , sealing cone 50 is displayed upright, from a side view. Here the bottom channel 56 is clearly displayed, as is through slot 54 , rising vertically from base to top of truncated cone 50 . Partial slots 58 are also shown, but in the preferred distribution of slots, partial slots 58 would be obscured in this view, as they lie on the rear side of the cone as viewed from the side of through slot 54 .
[0032] FIG. 7 displays the same cone from the base in a perspective view. The depressed base 56 is shown, with through slot 54 and partial slots 56 displayed to advantage.
[0033] The entire stuffing box 100 has a cap and a base. The cap is shown in FIG. 8 . The cap preferably has various levels of fit, providing microchannels for oil to flow in and around the cones.
[0034] FIG. 9 shows the base of the entire stuffing box. Although not seen in this side view, the base is also hollowing, in order to accommodate the polished rod. Thus, there will be a through hole inside the base, from top to bottom, of the dimensions of the polished rod.
[0035] FIG. 10 shows how the present invention 100 fits into its designed operational environment. The standard oil pumpjack unit comprises a walking beam, a head, and a polished rod or ‘sucker rod. The polished rod extends down to the wellhead of the oil well. At the junction of the polished rod and wellhead, a stuffing box, such as that of the current invention, is placed to create a seal preventing oil leaks, and allowing the unit to pump oil from the ground.
[0036] As shown in FIG. 10 , the current invention 100 will act as a sleeve, or collar, around the polished rod as it meets the wellhead. The rod moves up and down, forcing oil to the surface, while the stuffing box preserves proper pressure and prevents leaks.
[0037] The new combination of the novel packless stuffing box and pressure set seal packs provides new and unobvious and patentable features that reduce the cost of producing an oil well with a pump jack unit.
[0038] While the invention has been described in connection with a preferred embodiment or embodiments, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. | An improved annular seal assembly and packless stuffing box for an oil pumping unit of the type having a polished rod reciprocatingly extending therethrough and downhole to a pump located at the lower end of a borehole. The stuffing box has a main body that terminates in a tubing adaptor at the lower end thereof by which it can be mounted to the upper end of the tubing of a wellhead. The main body houses the annular seal assembly that includes a pressure set seal pack for sealingly engaging the polished rod. The polished rod reciprocatingly extends through the seal assembly and main body. The seal assembly includes paired metal annular cones which are capable of sealing under conditions present in the stuffing box. The seal assembly withstands such conditions far longer than traditional seal assemblies, thus reducing cost and downtime of the pumping unit. | 4 |
BACKGROUND OF THE INVENTION
The invention concerns a device for infrared (IR) spectroscopic investigation of internal surfaces of a body, for example of blood vessels with an IR spectrometer and with an endoscope with light guide means to illuminate the surfaces.
Such a device is known from WO 95/11624.
In endoscopes of such devices, scattered light is guided from internal surfaces of a body, mostly from blood vessels or internal body cavities via light guides to an external outside detector. Generally, glass fiber bundles are used as light guides. The light intensity of the detected scattered light and therefore the signal strength is thereby essentially proportional to the product of glass fiber cross sections which guide the light along the endoscope to the exposure, and the cross section of those glass fibers which collect the scattered light and guide it to the outside detector.
These prior art devices have therefore the disadvantage that for a given total cross section of the glass fibers only a fraction of the cross section can be used for illumination of the internal surfaces since the remaining glass fibers serve for guiding the collected light to the outside.
Apart from this, the collecting surface, i.e. the possible range of observation, is limited by the cross section of the collecting glass fibers and therefore relatively small in comparison to the total coating surface of the endoscope. The collecting fibers, suitable for spectroscopy (e.g. quartz) transfer the collected light only within a relatively narrow acceptance angle (generally a cone with ±10°), leading to an additional strong spatial limitation of the light acceptance of scattered light by the endoscope.
From DE 27 46 614 A1, an endoscope is known with light guide means to illuminate investigated surfaces. The illuminating light for the endoscope comes from a cold light source or from illuminating diodes located at the distal end, but from a spectrometer. DE 27 46 614 A1 is only concerned with imaging, not with spectroscopy.
In U.S. Pat. No. 4,403,273, a rod-shaped reflection unit for the illumination system of an endoscope is presented which allows a particularly large field of view of more than 100°.
In DE-GM 19 20 775, at the distal end of an endoscope a fiber light guide is bent by about 90°, polished at its flat end and covered by an opal glass plate. Insertable optics enable sidewise directed observation.
In U.S. Pat. No. 5,058,568, it is suggested to use the protective metal cover weave or other elements of a flexible endoscope for electric connections, which can lead e.g. to a video chip at the distal end.
U.S. Pat. No. 4,674,515 describes a rotatable ultrasound head of an endoscope.
U.S. Pat. No. 4,782,818, finally, discloses an endoscope to illuminate internal body surfaces with visible light for therapeutic reasons.
It is therefore the purpose of the present invention to present an device of the kind described above which comprises, for otherwise equal conditions, an increased signal strength and thereby the possibility to reduce the measuring time for equal signal quality.
SUMMARY OF THE INVENTION
According to the invention, this aim is achieved in a way, equally surprisingly simple and effective, in that at the proximal end IR light is directed from the IR spectrometer into the light guide means and that at the distal end of the light guide means there is arranged a detector for detecting IR light scattered from the illuminated surface and transforming it into electric signals.
By this detector arrangement no "return guide" for the collected scattered light is needed any more in the light guide means, so that the total light guiding cross section of the light guide means can fully be used to illuminate the surfaces under investigation. The accepting surface of the endoscope of the invention is merely limited by the detector design but not by the cross section of "return" glass fibers. The angular limitation of the acceptable scattered light due to the relatively small acceptance angle of glass fibers is also not relevant any more. In this way, for an equally large outer circumference of the endoscope, a considerably higher light yield can be achieved and thereby a considerably higher signal strength, so that for a comparable quality of the spectra a considerably shorter measuring time is required compared to conventional endoscopes.
An embodiment of the device according to the invention is particularly preferred where the detector comprises a sensitive detector surface which is larger than the cross section of the light exit surface at the distal end of the light guide means. In this way, also the diffusively scattered light of the investigated surface can be collected and thereby the light and signal yield of the device according to the invention can be considerably improved over conventional ones.
The IR spectrometer is preferably an FTIR spectrometer with an interferometer whose interfering light beam is coupled into the light guide means at their proximal end and which spectrometer converts the electric detector signals into an interferogram and by means of Fourier transformation into an IR spectrum.
Since a detector at the distal end is used, the IR light has to pass the spectrometer prior to entering the light guide means. Fourier spectrometer have a much better light yield compared to monochromators. However, in embodiments, the IR spectrometer may also be a dispersive system, i.e. a grating or prism spectrometer with entrance and exit slits.
The light guide means may comprise one or more commercially available glass fiber bundles.
In a preferred improvement of these embodiments, means to deflect the light by about 90° are provided at the distal end of the light guide means. In this way, an investigation range can be illuminated extending crosswise to the longitudinal endoscope axis as is typically the case with blood vessels.
The deflection may be effected by a tilted mirror or by a prism fitted onto the glass fiber bundle.
In an improvement that can be manufactured particularly easily and therefore cheaply, the means to deflect the light are formed by a prismatic cut of the glass fiber ends at about 45°. The light deflection is based upon total reflection or a reflective coating of the tilted surfaces.
In embodiments, the space between the fibers of the glass fiber bundle is filled with a material that, in the spectral range of interest, comprises a refractive index such that the refractive index difference between fiber and material is small enough for transmission of the IR light incident at nearly right angle and emerging from other fibers due to total reflection at their cut ends.
In this way the light bundles emerging e.g. from the central fiber can pass the peripheral fibers largely without reflection losses.
In order to ensure guidance of the IR light inside the fibers, their surfaces can be reflectively coated outside the distal region where the light leaves the fibers.
Preferably, the space between the fibers of the glass fiber bundle are at least in the region where the light leaves the fibers filled with a material which, in the spectral range of interest, comprises a refractive index such that the refractive index difference between fiber and material is large enough to guide the IR light inside the fibers but small enough for transmission of the IR light incident at nearly right angle and emerging from other fibers due to total reflection at their cut ends.
The problem that the outer fibers are in the way of the light deflected out of the inner fibers can be avoided in an elegant way by the following preparation procedure: After the prismatic (or cone shaped) cut and polishing, the longest fibers of the fiber bundle are pulled back in such a way that a staircase shaped arrangement is formed in the region of the light deflection in such a way that the light emerging out of a particular fiber deflected at an angel of about 90° is not blocked by other fibers. The fibers that during the cutting and polishing had still been the longest ones become the shortest ones at the distal end and vice versa.
However, apart from this, any other optical means to deflect light can also be used.
In a particularly preferred embodiment of the device according to the invention, the sensitive detector surface is placed directly on a coating surface of the light guide means. In this way, the detector practically requires no extra room and the endoscope of the device according to the invention can be constructed in a particularly compact manner.
In an advantageous improvement of this embodiment, provision is made that at the distal end of the light guide means the deflected light emerges within a limited angular range essentially in one direction on one side of the light guide means and that the sensitive detector surface is arranged on that side of the coating surface of the light guide means. In this way, a defined location of the internal surface surrounding the endoscope can be investigated selectively, whereby the arrangement of the sensitive detector surface on the same side where the light emerges leads to a particularly high yield of scattered light in relation to the detector surface.
A particularly advantageous improvement of this embodiment is characterized in that the deflected light emerges from a, preferably circular, mask on the side of the light guide means and that the sensitive detector surface is arranged on this side of the coating surface around the mask aperture. In particular, by using the mask, a collimation of the illuminating light and thereby a collimation onto a particularly small investigation surface precisely to the point can be achieved. Since the sensitive detector surface immediately surrounds the mask aperture, the detected light yield is further optimized.
Alternatively, in another advantageous embodiment of the device according to the invention, the deflected light may emerge out of an annular mask encircling the coating surface of the light guide means and the sensitive detector surface is arranged annularly about the coating surface of the light guide means, preferably on both sides of the annular mask aperture. In this way, for fixed endoscope, a complete annular surface range around the endoscope can be investigated simultaneously.
In a particularly preferred embodiment, the sensitive detector surface consists of a, preferably 1 to 10 μm thick, lead sulfide (PbS) layer which is particularly suited to accept infrared light.
In a further embodiment of the device according to the invention, the detector comprises a commercially photo resistor available at low cost.
The endoscope of the device according to the invention is particularly compact in embodiments where conducting strips are placed onto the coating surface of the light guide means, preferably by vapor deposition, to conduct the electric signals produced in the detector.
In an alternative embodiment, thin wires are provided to conduct the electric signals produced in the detector, preferably inside a channel in the center of the light guide means. This embodiment, too, does not enlarge the outer circumference of the endoscope.
In a particularly preferred improvement of this embodiment, the distal end of the light guide means can be mechanically manipulated by means of the thin wires. In this way, the signal wires serve a further function which had otherwise to be taken over by other components, so that, by this modification, the endoscope of the device according to the invention can again be designed in a particularly compact manner.
In a further, alternative embodiment, commercially available metal coated glass fibers, in particular gold coated glass fibers, are provided to conduct the electric signals generated in the detector.
Particularly preferred is also an embodiment of the device according to the invention, where the light guide means comprises at its distal end immediately after the detector a digitizing unit to digitize the electric signals generated by the detector. In this way, the signal received by the detector can be transported over far distances in digitized form even for small signal strengths.
A further advantageous embodiment is characterized in that a rotatable component is arranged at the distal end of the light guide means which can be manipulated from the other end of the light guide means and which deflects the light emerging out of the light guide means in a direction corresponding to the respective rotation angle of the rotatable component. In this way, the azimuthal resolution of the endoscope of the device according to the invention can alternatively be limited to a small angular range or be extended to an annular range around the entire surrounding surface, for example a blood vessel wall.
The same effect can be achieved by an alternative embodiment, where the endoscope of the device according to the invention is rotatable about its longitudinal axis. In comparison to the embodiment described above, there is, however, the disadvantage that the endoscope must be rotated over its entire length, which can lead to complications at locations with narrow passages, in particular during medical investigations at the point of insertion of the endoscope into the human body.
Also advantageous is an embodiment where the detector can be translated along the longitudinal axis of the endoscope. In this way, for fixed endoscope, measurements reflecting a longitudinal dependence become nevertheless possible.
In a particularly preferred embodiment, the light guide means comprises at its distal end an ultrasound head, preferably rotatable about the longitudinal endoscope axis. In this way, critical locations, for example narrow vessel passages, can be pre-localized by ultrasound measurements. Subsequently, specific infrared measurements can be performed, for example to identify the kind of tissue or depositions.
In a particularly compact improvement of this embodiment, the signal leads for the ultrasound head coincide with the electric leads which conduct also the electric signals from the detector receiving IR light. Separation of the two signal kinds may for example be effected by using disjunct voltage, current or frequency ranges and possibly by transfer of the IR detector signal in digital form and of the ultrasound signal in analogue form.
Further advantages of the invention result from the description and the drawing. The above mentioned features and those to be further described below in accordance with the invention can be utilized individually or collectively in arbitrary combination.
The embodiments shown and described are not to be considered as exhaustive enumeration, rather have exemplary character only for the description of the invention.
The invention is represented in the drawing and is further explained in connection with embodiments.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a schematic three-dimensional representation of an endoscope of a device according to the invention with a circular mask;
FIG. 2 shows an endoscope of a device according to the invention with a circumferential annular mask;
FIG. 3 shows a detail of a schematic longitudinal cross section across an endoscope of a device according to the invention with sidewise deflection of the illuminating light in a direction as in FIG. 1;
FIG. 4 shows a detail of a schematic longitudinal cross section across an endoscope of a device according to the invention with annular light deflection as in FIG. 2;
FIG. 5a shows a schematic cross section across an endoscope of a device according to the invention with vapor deposited conducting strips; and
FIG. 5b shows a schematic cross section across an endoscope of a device according to the invention with conducting wires running in a channel.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The three dimensional representation in FIG. 1 shows the distal end of the light guide means of an endoscope 10, serving to infrared (IR) spectroscopically investigate internal surfaces of a body, as for example internal walls of a blood vessel, stomach, intestines or the like. Not visible in FIG. 1, endoscope 10 internally contains light guide means, generally comprising glass fiber bundles. At the distal end of endoscope 10, the light, guided along the light guide means, is deflected by about 90° and emerges from a mask 11, being circular in the embodiment shown, in a direction at right angles to the endoscope 10 axis in the form of a light beam in a limited angular range and illuminates a corresponding spot of the surface under investigation. The light, back-scattered from there, is collected by means of a detector 12 at least to large extent and transformed into electric signals, which are transferred via leads 13 to a digitizing unit 14. From this, the digitized signals are conducted to the outside for further processing, via leads 15, which, in the embodiment shown, are vapor deposited onto the coating surface of the endoscope.
At the lowest end of endoscope 10, an ultrasound head 16 is schematically represented, with which advance ultrasound measurements of the investigation area can be performed prior to the IR spectroscopic investigations. In this way, for example critical locations as e.g. narrow vessel passages or depositions can at first be pre-localized by the ultrasound measurements and subsequently a specific tissue identification or generally of substances at the investigation area can be performed. Preferably, ultrasound head 16 will be rotatable about the longitudinal endoscope 10 axis. In order to keep the endoscope 10 as compact a possible regarding its outer dimensions, the same electric leads 13, 15 can be used for both, the electric measuring signals from ultrasound head 16 as well as for the electric measuring signals from detector 12, whereby both electric signal kinds may for example be separated by using different voltage, current or frequency ranges.
Detector 12 collecting IR light scattered by the illuminated surface, and converting it into electric signals, is flat in the presented embodiment, whereby the sensitive detector surface is attached to a coating surface of endoscope 10. The sensitive detector surface can for example consist of a, preferably 1 to 10 μm thick, PbS layer. In particular, detector 12 can comprise a photo resistor.
In the embodiment shown in FIG. 1, the sensitive detector surface of detector 12 is arranged around mask aperture 11. Since back-scattered light from the object surface can only be collected on the side of the mask aperture, in this case the sensitive detector 12 surface is limited approximately to a half cylinder around the mask aperture 11. The sensitive detector surface is nevertheless still considerably larger than the light exit area at the distal end of the light guide means of endoscope 10, so that at least most of the IR light scattered at the examination surface can be collected. Moreover, the detector surface according to the invention does not lead to the usual angular limitations of glass fibers for the observed light due to the finite acceptance angle of glass fibers.
In FIG. 2 a further embodiment is shown, where instead of a circular mask 11 the endoscope 20 comprises a circumferential annular mask 21, from which the light 27, deflected inside the endoscope 20 by about 90°, emerges to all sides. The sensitive detector 22 surface consists in this case of two circumferential annular strips arranged at both sides of annular mask aperture 21. With such an arrangement, an entire annular surface range around the endoscope 20 can be investigated simultaneously.
The above mentioned light deflection at the illuminated end of light guide means of about 90° can for example be effected by a fitted prism or a prismatic cut of the light guide ends. In FIG. 3 an axial section at the distal end of an endoscope 30 of a device according to the invention is represented in a longitudinal cross section. IR light from a spectrometer 1 enters the light guide means. A central IR light beam 37 runs inside a glass fiber bundle 39 and impinges on a prism surface 38 at the distal end of the glass fiber bundle 39 and is deflected in the shown figure towards the left side. It exits sidewise out of the endoscope 30, through a mask aperture 31, formed by an e.g. circular hole in the sensitive surface of a detector 32. In combination with other light beams from neighboring fibers of glass fiber bundle 39 a collimated light beam is thereby formed being angularly limited, which illuminates a correspondingly limited investigation surface located sidewise from the endoscope 30. Insofar FIG. 3 represents the possible "interior" of an endoscope 10 according to FIG. 1.
FIG. 4 shows also in a longitudinal cross section a detail of an endoscope 40, exhibiting similar annular circumferential illumination characteristics as endoscope 20 of FIG. 2. In a glass fiber bundle 49 there are schematically represented light beams 47 originating in spectrometer 1, impinging at the end of the light guide means onto a cone shaped tilted surface 48 of a correspondingly shaped deflecting component attached to the fiber bundle end, where they experience a sidewise total reflection by 90°. The tilted surface 48 may also be reflectively coated. The light beams 47 then exit through an annular mask aperture 41 in all directions perpendicular to the endoscope 40. Annular mask 41 is formed by the sensitive surfaces of a detector 42 which are arranged as strips above and below the aperture range around the coating surface of endoscope 40.
FIGS. 5a and 5b, each show a schematic cross section across an endoscope of a device according to the invention. Tightly packed glass fiber bundles 59a, 59b can be recognized which serve to guide the illuminating light.
The endoscope represented in FIG. 5a comprises conducting strips 55a which are vapor deposited sidewise onto the coating surface of endoscope 50a to conduct the measuring signals generated by the detector.
In contrast thereto, endoscope 50b of FIG. 5b comprises two wires 55b in an internal channel between the glass fibers 59b, which wires 55b are represented with a rectangular cross section for better distinction which serve also to conduct the detector signals and which, in practice, would exhibit a round, considerably smaller cross section. In addition, the wires 55b, if correspondingly arranged, can take over mechanical tasks, e.g. effect a rotation of an ultrasound head at the distal end of endoscope 50b.
The endoscope of the device according to the invention can be designed such that at the distal end of the light guide means a rotatable component is arranged which can be manipulated and which deflects the light emerging from the light guide means in a direction corresponding to the respective rotation angle of the rotatable component. By rotating this head piece of the endoscope, measuring of a sequential series of spectra across the entire circumference of the surrounding surface which has to be investigated becomes possible.
In addition, a longitudinal shift of the optical system inside the endoscope can also be possible, whereby also a translatoric scan of the surface regions under investigation and from this a large scale investigation is possible.
In particular if already data are generated in digital form at the distal end of the endoscope, the detector and/or a corresponding AD converter could also transmit these date in a wireless manner without electric leads. Detector and/or transmitter could be equipped with a microbattery, i.e. electric leads could be omitted completely. | A device for infrared (IR) spectroscopic investigation of internal surfaces of a body, for example of blood vessels, comprising an endoscope (10) with light guide means to illuminate the surfaces is characterized in that at the distal end of the light guide means there is arranged a detector (12) for detecting IR light scattered from the illuminated surface and transforming it into electric signals. For otherwise identical conditions, compared to comparable known devices, the device according to the invention offers a higher signal strength and thereby the possibility to shorten the measuring time for equal signal quality. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 60/955,085, entitled “Control System for Blowout Preventer Stack”, filed on Aug. 10, 2007, and U.S. Provisional Patent Application No. 60/954,919, entitled “Control Module for Subsea Equipment”, filed on Aug. 9, 2007, each of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates in general to subsea well drilling and in particular to a control system for controlling a blowout preventer stack connected between the subsea wellhead assembly and a riser.
BACKGROUND OF THE INVENTION
[0003] Subsea Control Modules (SCMs) are commonly used to provide well control functions during the production phase of subsea oil and gas production. Typical well control functions and monitoring provided by the SCM can include: 1) actuation of fail-safe return production tree actuators and downhole safety valves; 2) actuation of flow control choke valves, shut-off valves, etc.; 3) actuation of manifold diverter valves, shut-off valves, etc.; 4) actuation of chemical injection valves; 5) actuation and monitoring of Surface Controlled Reservoir Analysis and Monitoring Systems (SCRAMS) sliding sleeve, choke valves; 6) monitoring of downhole pressure, temperature and flow rates; and 7) monitoring of sand probes, production tree and manifold pressures, temperatures, and choke positions.
[0004] The close proximity of the typical SCM to the subsea production tree, coupled with its electro-hydraulic design allows for quick response times of tree valve actuations. The typical SCM receives electrical power, communication signals and hydraulic power supplies from surface control equipment. The subsea control module and production tree are generally located in a remote location relative to the surface control equipment. Redundant supplies of communication signals, electrical, and hydraulic power are transmitted through umbilical hoses and cables of various length, linking surface equipment to subsea equipment. Electronics equipment located inside the SCM conditions electrical power, processes communications signals, transmits status and distributes power to devices such as solenoid piloting valves, pressure transducers and temperature transducers.
[0005] Low flow rate solenoid piloting valves are typically used to pilot high flow rate control valves. These control valves transmit hydraulic power to end devices such as subsea production tree valve actuators, choke valves and downhole safety valves. The status condition of control valves and their end devices are read by pressure transducers located on the output circuit of the control valves. Auxiliary equipment inside the typical SCM consists of hydraulic accumulators for hydraulic power storage, hydraulic filters for the reduction of fluid particulates, electronics vessels, and a pressure/temperature compensation system.
[0006] Recognized by the inventors is that the application of production control system technology incorporated into a modular approach to drilling control systems can allow for additional redundancy, can enhance survivability during deployment, operation, and retrieval, and can reduce maintenance repair times and costs, along with many other benefits.
SUMMARY OF THE INVENTION
[0007] For drilling applications a subsea blowout preventer assembly is provided. The assembly includes a lower marine riser package (LMRP) and a blowout preventer stack (BPS). The LMRP includes a first junction plate and said BPS includes a second junction plate. The junction plates connect at least one of hydraulic, electrical or communications signal from the LMRP to the BPS. The assembly includes at least one LMRP module baseplate positioned on the LMRP and at least one LMRP control module configured to control electrical or hydraulic functionality associated with the LMRP. The LMRP control module is releasably connected to the LMRP module baseplate. The assembly also includes at least one BPS module baseplate positioned on the BPS and at least one BPS control module configured to control electrical and/or hydraulic functionality associated with said BPS. The BPS module is releasably connected to the BPS module baseplate. The LMRP and BPS modules are configured to be installed and retrieved by a remotely operated vehicle.
[0008] In certain embodiments, the overall assembly control systems are redundant, wherein two or more of the LMRP control modules are present on the LMRP and two or more of the BPS control modules are present on the BPS, thereby forming redundant assembly control modules. In certain embodiments, the redundant LMRP modules do not function cooperatively and the redundant BPS modules do not function cooperatively.
[0009] In certain embodiments, the LMRP module baseplate can also include at least one auxiliary LMRP module selected from the group consisting of a subsea regulator module, subsea valve module, subsea filter module, subsea accessory module, c subsea shuttle valve module, subsea acoustic system module, subsea pressure transducer module and subsea temperature transducer module. In certain embodiments, the BPS module baseplate also includes at least one auxiliary BPS module selected from the group consisting of a subsea regulator module, subsea valve module, subsea filter module, subsea accessory module, subsea shuttle valve module, subsea acoustic system module, subsea pressure transducer module and subsea temperature transducer module.
[0010] In certain embodiments, the assembly also includes a parking base plate positioned on the LMRP or the BPS, said parking base plate comprising at least two parking receptacles adapted to receive any of said modules.
[0011] In another aspect, a subsea blowout preventer assembly is provided that includes a lower marine riser package (LMRP) and a blowout preventer stack (BPS), wherein the LMRP includes a first junction plate and the BPS includes a second junction plate. The junction plates connect at least one of the hydraulic, electrical or communications signals from the LMRP to the BPS. Additionally, the assembly includes at least one LMRP module baseplate positioned on the LMRP and at least one releasably connected LMRP control module configured to control electrical or hydraulic functionality associated with the LMRP. Additionally, the assembly includes at least one auxiliary LMRP module selected from the group consisting of a subsea regulator module, subsea valve module, subsea filter module, subsea accessory module, subsea shuttle valve module, subsea acoustic system module, subsea pressure transducer module and subsea temperature transducer module. The assembly also includes at least one BPS module baseplate positioned on said BPS and at least one releasably connected BPS control module configured to control electrical or hydraulic functionality associated with the BPS. In addition, the assembly includes at least one auxiliary BPS module selected from the group consisting of a subsea regulator module, subsea valve module, subsea filter module, subsea accessory module, subsea shuttle valve module, subsea acoustic system module, subsea pressure transducer module and subsea temperature transducer module. The modules are configured to be installed and retrieved by a remotely operated vehicle.
[0012] In another aspect, a method for controlling a subsea blowout preventer assembly is provided, wherein the assembly includes a lower marine riser package (LMRP) and a blowout preventer stack (BPS). The LMRP includes a first junction plate and said BPS includes a second junction plate. The LMRP and BPS are coupled at said first and second junction plates, and the junction plates connect at least one of hydraulic, electrical or communication signal from the surface to the assembly. The method includes the steps of providing at least one LMRP module baseplate positioned on the LMRP and providing at least one LMRP control module releasably connected to the LMRP module baseplate configured to control electrical or hydraulic functionality associated with the LMRP. The method also includes the steps of providing at least one auxiliary LMRP module selected from the group consisting of a subsea regulator module, subsea valve module, subsea filter module, subsea accessory module, subsea shuttle valve module, subsea acoustic system module, subsea pressure transducer module and subsea temperature transducer module, said auxiliary LMRP module being releasably connected to the LMRP module baseplate. At least one BPS module baseplate positioned on said BPS is provided; and at least one BPS control module releasably connected to the BPS module baseplate and configured to control electrical or hydraulic functionality associated with said BPS is provided. Additionally, the method includes providing at least one auxiliary BPS module selected from the group consisting of a subsea regulator module, subsea valve module, subsea filter module, subsea accessory module, subsea shuttle valve module, subsea acoustic system module, subsea pressure transducer module and subsea temperature transducer module, said auxiliary BPS module being releasably connected to the BPS module baseplate. Finally, the method includes the steps of installing or removing at least one module selected from the group consisting of the LMRP control module, the LMRP auxiliary module, the BPS control module, and the BPS auxiliary module with a remotely operated vehicle (ROV).
[0013] In another aspect, a method for replacing a module on a subsea blowout preventer assembly, the assembly including a lower marine riser package (LMRP) and a blowout preventer stack (BPS), wherein the LMRP includes at least one LMRP module baseplate and the BPS includes at least one BPS module baseplate. The LMRP module baseplate is configured to receive at least one LMRP module and the BPS module baseplate is configured to receive at least one BPS module. The LMRP and said BPS each include at least one parking receptacle. The method for replacing includes the steps of: utilizing a remotely operated vehicle (ROV) to transport at least one replacement module from the surface to a module baseplate, positioning said replacement module in a first parking receptacle adapted to receive a module, and utilizing the ROV to remove at least one module from either the LMRP module baseplate or said BPS module baseplate, thereby creating an empty position in the module baseplate. The method further includes utilizing the ROV to position the removed module in a second parking receptacle adapted to receive a module and utilizing the ROV to retrieve the replacement module from the first parking receptacle and position said replacement module into the empty position in the module baseplate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic view illustrating a lower marine riser package connected to a blowout preventer stack in accordance with this invention.
[0015] FIGS. 2A and 2B are a schematic of a subsea control system for the lower marine riser package and the blowout preventer of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0016] Referring to FIG. 1 , a subsea well is shown in the process of being drilled. The subsea well includes a subsea wellhead assembly located at the sea floor. A blowout preventer (BOP) stack 13 secures to the subsea wellhead assembly by means of a hydraulically actuated connector 11 . BOP stack 13 is a complex device for controlling pressure in the well. BOP stack 13 will have a number of rams 15 , some of which can close on or around drill pipe or casing. Other rams 15 can shear pipe to form a complete closure in the event of an emergency.
[0017] BOP stack 13 is connected to a lower marine riser package (LMRP) 19 . LMRP 19 includes a connector 20 that is hydraulically actuated for connecting to BOP stack 13 . As shown in FIG. 1 , an annular blowout preventer (BOP) 17 can be a part of LMRP 19 and mounts on top of connector 20 for closing around pipe. Alternately, annular BOP 17 can be part of BOP stack 13 and not part of LMRP 19 ; or both BOP stack 13 and LMRP 19 can include an annular BOP 17 . LMRP 19 is connected to the lower end of a drilling riser 21 . Drilling riser 21 includes a large diameter central pipe through which drilling tools can be lowered. A number of auxiliary or rigid conduits 23 can be spaced around the central pipe for delivering hydraulic fluid and for other functions. Additionally, an electrical cable that can include a bundle of wires, and optionally includes fiber optic lines for providing communications and electrical power, extends alongside riser 21 from a drilling vessel at the surface. LMRP 19 and BOP stack 13 includes one or more modules 25 that are adaptable to perform many functions, including the control of the LMRP or BOP stack.
[0018] All modules 25 of both the LMRP and the BOP stack are installable and are retrievable by remotely operated vehicle (ROV). LMRP 19 can include a number of retrievable modules 25 that are releasably mounted to it. Similarly, BOP stack 13 can include a number of retrieval modules 25 that are releasably mounted to it. Each module 25 is sufficiently small and lightweight that it can be installed and retrieved using a ROV. Modules 25 on LMRP 19 can control various functions on LMRP 19 and modules 25 on BOP stack 13 can control various functions on BOP stack 13 . Modules 25 can be placed near the functionality that they control and/or with which they are associated, in contrast to prior art control devices associated with the control of a BOP stack, which are generally large and are located relatively distant from the functionality with which they are associated, and normally on the LMRP.
[0019] In being remotely retrievable, the replacement of one or more modules can be accomplished with a remotely operable vehicle, which can thereby eliminate the need to pull the entire apparatus, including the LMRP. Use of the ROV during maintenance operations results in reduced downtime and increased savings.
[0020] LMRP 19 includes at least one junction plate 29 , and in certain embodiments, two junction plates, that stab into mating engagement with mating junction plates 31 on BOP stack 13 when LMRP 19 is connected to BOP stack 13 . Junction plates 29 , 31 connect hydraulic, electrical, and/or fiber optic lines for supplying hydraulic fluid pressure, electrical power and communications to and from the LMRP 19 to BOP stack 13 .
[0021] Exemplary modules can include: subsea control modules, subsea regulator modules, subsea valve modules, subsea filter modules, subsea shuttle (valve) modules, and subsea accessory modules, in addition to modules that control or are associated with subsea chemical injection, subsea choke inserts, subsea acoustic systems, subsea pressure and/or temperature transducers.
[0022] An example of several of the exemplary modules 25 and the functions they control are illustrated in FIGS. 2A and 2B . The overall control system is redundant, with the modules 25 shown in FIG. 2A , arbitrarily marked as “Yellow System”, being duplicated by the modules 25 shown in FIG. 2B and arbitrarily marked as “Blue System”. For convenience, the same references numerals are used for each system in most instances. The Yellow System can perform all functions of LMRP 19 and BOP stack 13 without requiring the input from the Blue System, and similarly the Blue System can perform all functions of LMRP 19 and BOP stack 13 without requiring the input from the Yellow System. In certain embodiments, the Yellow and Blue Systems are not operated at the same time. A control module 25 of the Yellow System is not typically operated with the Blue System and vice versa. An exception to this can be found in embodiments wherein the conduit valve package 36 may be operated by either Yellow or Blue Systems. Similarly, in certain embodiments, the control modules 25 mounted to LMRP 19 only control functions of LMRP 19 , and do not control the functions of BOP stack 13 and vice versa.
[0023] LMRP 19 may include singular or redundant hydraulic fluid supply equipment for both the modules 25 of LMRP 19 and for the modules 25 of BOP stack 13 . The hydraulic fluid supply equipment includes a base plate 33 on the Yellow System ( FIG. 2A ) and a base plate on the Blue System ( FIG. 2B ), wherein the base plates 33 can include receptacles and couplings for supporting at least one filter module 35 . Filter module 35 , like all of the other modules 25 , can be sufficiently small and lightweight so as to be installed and retrieved by an ROV. Each filter module 35 can include high flow rate filters designed to provide for local filtration of hydraulic fluid which can be supplied down one or more of the rigid conduits 23 extending alongside the riser. Additionally, a flow meter can be located within filter module 35 or base plate 33 for measuring hydraulic fluid flow through the system. A hydraulic regulator may be located within filter module 35 for stepping down supply pressure. In certain embodiments, filtered hydraulic fluid can flow from filter module 35 through module base plate 33 as a supply to all of the other hydraulically actuated equipment on both LMRP 19 and on BOP stack 13 . One or more output lines 37 , connected to an accumulator bank 38 , leads to LMRP junction plate 29 for supplying hydraulic fluid pressure to the accumulators 95 of BOP stack 13 . In certain embodiments, additional output lines 41 can be connected to the LMRP base receptacles 47 and to junction plates 29 , 31 and further connect to the BOP base plates 69 , supplying fluid to various modules 25 .
[0024] Rigid conduit package 36 can be made up of subsea valve module 39 , base plate 33 and filter module 35 . In certain embodiments, a subsea valve module 39 can mount to module base plate 33 on both the Yellow System and the Blue System. Subsea valve module 39 can include a number of directional control valves, which are opened and closed by hydraulic pressure supplied by pilot valves that may be located in a control module 51 . These directional control valves can be used for various functions, such as for example, isolation and flushing of the rigid conduits 23 , filter selection, as well as valves for selection, isolation of pilot, and testing of hydraulic circuits. Module base plate 33 is connected by hydraulic fluid lines 37 and 41 to one of the junction plates 29 . Subsea valve modules 39 are installable and retrievable by an ROV.
[0025] In certain embodiments, both the Yellow and Blue Systems are connected to shuttle valve module base plate 43 mounted to LMRP 19 . One or more shuttle valve modules 45 can be retrievably mounted to each module base plate 43 . The shuttle valves in shuttle valve modules 45 can be connected to valve actuators and other equipment, such as for example, annular BOP 17 or LMRP connector 19 . Those functions can include connecting and disconnecting the connection between LMRP 19 and BOP stack 13 , closing annular BOP 17 and operating other LMRP hydraulically controlled functions. The hydraulic lines leading to shuttle valve base plate 43 are not shown. Each shuttle valve base plate 43 can be connected to both the hydraulic fluid lines leading from control valves of the Yellow System and from control valves of the Blue System. Depending on whether the pressure is being delivered by the Yellow System or the Blue System, each shuttle valve can automatically shift to direct the hydraulic fluid pressure to the valve actuator, connector or other equipment. Each shuttle valve module 45 can receive fluid from either the Blue or the Yellow System and can direct the fluid to the designated component of LMRP 19 . In certain embodiments, module base plates 43 and one or more shuttle valve modules 45 can include a shuttle valve package 40 .
[0026] The Yellow and Blue Control Systems each have a control module base plate 47 mounted to LMRP 19 . Each control module base plate 47 includes receptacles for one or more control modules. In certain embodiments, a regulator module 49 can be retrievably mounted to base plate 47 . Regulator module 49 can include a number of hydraulic regulators that provide the means for regulating the system output pressure for the different hydraulic circuits for functions on LMRP 19 . Preferably, in certain embodiments, each regulator is independently adjustable. In certain other embodiments, the solenoid pilot regulator can be a manual regulator that is preset at the surface, while the other regulators can be adjusted remotely subsea. Other configurations are also possible. Hydraulic fluid lines 57 supply hydraulic fluid pressure from rigid conduit base plate 33 to module 49 .
[0027] One or more subsea control modules (SCM) 51 can be retrievably mounted to each control module base plate 47 of LMRP 19 . The SCM can include a subsea electronic module (SEM) that can receive and decode multiplexed signals from the surface control unit. SCM 51 can include electronics as well as solenoid pilot valves and directional control valves. The electronics portion of each SCM 51 can be configured to receive communication signals from a surface control unit. The electronics portion can then decode the signals and convert them to hydraulic signals via electrically operated solenoid valves, which act as pilot valves for other elements such as hydraulically operated directional control valves. In certain embodiments, each SCM 51 is capable of controlling a number of hydraulic functions, either directly or as pilots to larger, high flow rate directional control valves. Some of those functions include housekeeping functions and others are control functions. Some of those functions can include, but are not limited to: operating the locking and unlocking of the connector of LMRP 19 to BOP stack 13 ; controlling the hydraulic regulators; and controlling various test valves and isolation valves on LMRP 19 . Hydraulic pilot pressure from one of the SCMs 51 will also control directional control valves in subsea valve module 39 located in rigid conduit valve package 36 .
[0028] In certain embodiments, a subsea valve module 55 also retrievably mounts to each module base plate 47 . In certain embodiments, subsea valve module 55 can include high flow rate directional control valves for controlling some of the large functions on LMRP 19 , such as the annular BOP 17 ( FIG. 1 ), which is part of LMRP 19 in the figure. The directional control valves are operated via hydraulic pilot signals received from one of the SCM's 51 . The fluid flow from subsea valve module 55 leads to shuttle valve module base plate 45 , which direct the fluid to the particular function. In certain embodiments, LMRP control package 32 can include base plates 47 and modules 49 , 51 and 55 .
[0029] In certain embodiments, there can be two electrical cables 58 , 60 extending from the drilling vessel. Each electrical cable 58 , 60 independently supports power and communications to both the Yellow and Blue Systems. An electrical termination and connection assembly 59 (TCA) is located at the lower end of each electrical cable 58 , 60 . Each TCA 59 includes connections for power and communication, which can optionally include fiber optic lines. Each TCA 59 includes electrical lines 61 , 63 leading from it for supplying power to the Yellow and Blue Systems, respectively. Line 61 of each TCA 59 leads to Yellow System control module base plate 47 for supplying power and communications to Yellow System SCMs 51 . Line 63 of each TCA 59 leads to Blue System control module base plate 47 ( FIG. 2B ) for supplying power and communications to Blue System SCMs 51 . In certain embodiments, each TCA 59 can provide one line 61 (Yellow) and one line 63 (Blue). Thus, in embodiments with two TCAs (one for control cable 58 and one for control cable 60 ), there are two independent and redundant power and communication connections feeding the Yellow System and likewise two independent and redundant power and communication connections feeding the Blue System. Other configurations are possible, and are within the scope of this invention.
[0030] The Yellow System can include an electrical line 65 that connects power and communications line 61 at control module base plate 47 and leads to junction plate 29 for delivering power and signals to the various Yellow System elements on BOP stack 13 . The Blue System can include a similar electrical line 67 that connects power and communications of line 63 at control module base plate 47 and leads to junction plate 29 for delivering power and signals to the various Blue System elements on BOP stack 13 . In certain embodiments, a mirror image of this configuration can connect to the redundant second set of power and communications signals from the other TCA 59 via base plates 47 to the other junction plate 29 to feed redundant power and communications signals to both the Yellow and Blue systems.
[0031] BOP stack 13 can include a Yellow System and a Blue System control module base plate 69 . In certain embodiments, each base plate 69 can include multiple receptacles that receive, for example, a subsea valve module 71 , one or more subsea control modules 73 and a regulator module 77 . Subsea valve module 71 can include high flow rate directional control valves similar to subsea valve module 55 . Subsea valve module 71 supplies hydraulic fluid pressure for BOP stack 13 functions such as opening and closing rams 15 . SCMs 73 can include electronics along with pilot valves and directional control valves for controlling the various functions on BOP 13 . These functions can include, for example, the various valves of BOP stack 13 , connector to subsea wellhead, choke and kill valves, as well as housekeeping functions, such as for example, increasing and decreasing hydraulic fluid pressure controlled by regulators in the regulator module 77 .
[0032] Regulator module 77 , similar to LMRP regulator module 49 , regulates the hydraulic fluid pressure for the hydraulic functions on BOP stack 13 , rather than the hydraulic functions on LMRP 19 . SCMs 73 control regulator module 77 to change the hydraulic fluid pressure for the various rams 15 as well as the connector to subsea wellhead 11 ( FIG. 1 ). Various hydraulic lines 79 lead from junction plate 31 to module base plate 69 for receiving hydraulic fluid pressure from rigid conduit base plate 33 . In certain embodiments, BOP control package 34 can include base plates 69 and modules 71 , 73 and 77 .
[0033] Electrical line 65 of junction plate 29 can supply electrical power and communication signals from electrical cable 58 to Yellow System SCMs 73 via electrical line 81 , which extends from BOP stack junction plate 31 . Electrical line 67 , also of junction plate 29 , supplies electrical power and communication signals from electrical cable 58 to Blue System SCM's 73 via electrical lines 83 , which extends from BOP stack junction plate 31 . A mirror image of this electrical connection arrangement provides redundant power and communications signals via the opposite junction plate set 29 and 31 , to the BOP stack SCMs 73 on both the Yellow and Blue Systems. In the event of failure of one electrical cable 58 or 60 , the other electrical cable 58 or 60 will supply all electrical power and communication signals to either the Yellow or Blue System, as needed.
[0034] BOP stack 13 includes a subsea module base plate 85 having receptacles adapted to receive shuttle valve modules 87 , which in turn are connected to various hydraulically actuated equipment, such as for example, pipe rams 15 ( FIG. 1 ). In certain embodiments, the shuttle valve modules 87 can be part of the shuttle valve package 40 .
[0035] A parking base plate 91 may optionally be mounted to BOP stack 13 or LMRP 19 . Parking base plate 91 preferably can include parking receptacles 93 adapted to receive any one of the modules 25 . In certain embodiments, an ROV would be able bring down a replacement module 25 and temporarily park it in one receptacle 93 in order to disconnect one of the other modules 25 . The ROV could then place the recently removed module 25 in the other parking receptacle 93 , pick up the replacement module and install it in one of the base plates. The ROV would then pick up the removed module from the receptacle 93 and retrieve it to the surface. BOP stack 13 also has a set of accumulators 95 that are supplied with hydraulic fluid through hydraulic line 97 leading from junction plate 31 .
[0036] During certain operations, the various modules 25 ( FIG. 1 ) on LMRP 19 perform functions associated with LMRP 19 and also provide filtration for all of the hydraulic systems, including those of BOP stack 13 . The various modules 25 of BOP stack 13 can be directed to the functions of BOP stack 13 . In certain embodiments, to connect BOP stack 13 to subsea wellhead 11 using the Yellow System, communication signals will be sent down one of the electrical lines 58 through lines 61 , 65 and 81 to one of the BOP stack subsea control modules 73 . That control signal will cause a pilot valve or a directional control valve to send hydraulic fluid pressure to subsea valve module 71 , which in turn supplies hydraulic fluid pressure to the connector via one of the shuttle valves in one of the shuttle valve modules 87 . If a function is required of LMRP 19 and the Yellow system is in use, the signal can be sent via electrical line 58 or 60 to one of the SCMs 51 of the Yellow System, which in turn can cause the hydraulic function to be performed through its pilot valves and/or directional control valves or through subsea valve module 55 , via one of the shuttle valves in one of the shuttle valve modules 45 .
[0037] In certain embodiments, when because of a storm or some other emergency, the vessel must be quickly moved, the operator may close rams 15 and disconnect LMRP 19 from BOP stack 13 . The operator would then be able to leave the location with riser 21 and LMRP 19 trailing behind. The various rams 15 would remain closed as no hydraulic pressure would exist to cause them to open. When returning, if due to damage, LMRP 19 cannot connect back to BOP stack 13 , the operator may be able to perform certain functions with BOP stack 13 without LMRP 19 . The operator would be able to do this by connecting electrical power and hydraulic power via an umbilical and flying lead to the receptacles in BOP stack junction plate 31 . That umbilical would supply hydraulic fluid pressure and signals directly from the vessel to either the Yellow or Blue System control modules 73 and to modules 71 , 77 and accumulators 95 . The operator could then open and close rams 15 and perform other functions interfacing with SCMs 73 or other modules.
[0038] In certain embodiments, the modules can be employed in retrofit applications. For example, in certain embodiments, the modules described herein can be employed on existing LMRP or BOP stack apparatuses to replace all or a portion of the control devices associated with said LMRP or BOP stack.
[0039] Although the following detailed description contains many specific details for purposes of illustration, one of ordinary skill in the art will appreciate that many variations and alterations to the following details are within the scope of the invention. Accordingly, the exemplary embodiments of the invention described below are set forth without any loss of generality to, and without imposing limitations thereon, the claimed invention.
[0040] The singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise.
[0041] Optional or optionally means that the subsequently described event or circumstances may or may not occur. The description includes instances where the event or circumstance occurs and instances where it does not occur.
[0042] Ranges may be expressed herein as from about one particular value, and/or to about another particular value. When such a range is expressed, it is to be understood that another embodiment is from the one particular value and/or to the other particular value, along with all combinations within said range.
[0043] This application is related to U.S. Provisional Patent Application No. 60/955,085, entitled “Control System for Blowout Preventer Stack”, filed on Aug. 10, 2007, and U.S. Provisional Patent Application No. 60/954,919, entitled “Control Module for Subsea Equipment”, filed on Aug. 9, 2007, each of which are incorporated herein by reference in their entirety.
[0044] Throughout this application, where patents or publications are referenced, the disclosures of these references in their entireties are intended to be incorporated by reference into this application, in order to more fully describe the state of the art to which the invention pertains, except when these reference contradict the statements made herein. | A modular control system consisting of multiple, remotely retrievable functional modules for controlling a blowout preventer stack. The various functional modules can be located on the lower marine riser package and blowout preventer stack positioned near the equipment with which they are associated, wherein this distribution of modules nearly eliminates the complex interface connection between the lower marine riser package and blowout preventer stack. Each of the functional modules is capable of being installed, retrieved or replaced with a single remotely operated vehicle (ROV) deployment from a vessel. The functional modules can be used to operate as a complete control system for a blowout preventer stack or can be used selectively individually or in various combinations to accommodate multiple control applications or upgrades of other control systems. | 4 |
This application is a continuation of application Ser. No. 230,600, filed Feb. 2, 1981, abandoned.
BACKGROUND OF THE INVENTION
The invention relates to a sewing machine, and more particularly relates to a selecting device of a double-function sewing machine which may produce different types of stitches, such as the ordinary lock stitches and the overlock stitches. The invention is directed to a sewing machine such as disclosed in the copending U.S. Pat. application Ser. No. 860,589 U.S. Pat. No. 4,267,786 which is provided with two separate stitch forming mechanisms for different types of stitches, each operatively and selectively connected through a transmission device to a single drive source such as a machine driving motor.
According to the invention, a selecting device is manually and selectively operated from an external dial to activate a clutch to connect one of the stitch forming mechanisms to the machine drive motor and at the same time to inactivate another clutch to disconnect the other of the stitch forming mechanisms from the machine driving motor. In addition, both stitch forming mechanisms are disconnected from the machine driving motor if a thread winding mechanism of the sewing machine is operated.
So far, home sewing machines have been structured only to produce lock stitches. Recently it has been generally desired to have a sewing machine which functions to provide lock stitching and overlock stitching which are indispensable for producing a well finished stitching work, and accordingly various constructions regarding such a sewing machine have been provided. However, since the sewing machine requires two different types of stitch forming mechanisms, it becomes bulky, complex in structure and difficult to operate, and also awkward in design.
SUMMARY OF THE INVENTION
The present invention aims to eliminate such defects and disadvantages of the prior art, and it is a primary object of the invention to provide a selecting device of simple structure which is manually and selectively operated to connect one of the lock stitch forming mechanisms and the overlock stitch forming mechanism to the machine driving motor and disconnect the other of the mechanisms from the machine driving motor. It is another object of the invention to provide a selecting device which is positively and securely operated to safeguard the disconnected stitch forming mechanism from the abrupt and unexpected drive by the machine driving motor. It is still another object of the invention to disconnect both of the stitch forming mechanisms from the machine driving motor when the thread winding mechanism is operated.
The other features and advantages of the invention will be apparent from the following description of a preferred embodiment in reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of a sewing machine of the invention;
FIG. 2 is a front elevational view of an inner mechanism of the sewing machine according to the invention;
FIG. 3 is a side elevational view of the mechanism shown in a vertical section;
FIG. 4 is a front elevational view of the mechanism shown in a vertical section;
FIG. 5 is a plan view of a first clutch of the invention partly shown in section;
FIG. 6 is a plan view of a second clutch of the invention partly shown in section;
FIG. 7 is an exploded view of a selecting device of the invention; and
FIG. 8 is an exploded view of a clutch mechanism of the invention.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1, the double-function sewing machine has a housing 1 in which a lock stitching mechanism (not shown) is arranged, and another housing 2 in which an overlock stitching mechanism (not shown) is arranged. These two stitching mechanisms are selectively connected to a single machine drive motor (not shown) by way of a clutch mechanism and a transmission mechanism when a selecting dial 3 is selectively operated. According to the invention, the lock stitching mechanism is connected to the machine drive motor when the mark 3a of the dial 3 is positioned in alignment with a mark of LOCK STITCH provided on the housing 1 while the overlock stitching mechanism is disconnected from the machine drive motor. On the other hand, the overlock stitching mechanism is connected to the machine drive motor when the mark 3a of the dial 3 is positioned in alignment with a mark of OVERLOCK STITCH while the lock stitching mechanism is disconnected from the machine drive motor.
FIG. 2 shows a selecting mechanism of the lock stitching mechanism and the overlock stitching mechanism, in which a control shaft 4 is turnably mounted in the housing 1. The control shaft 4 has one end protruded out of the housing 1 to carry thereon the selecting dial 3 in FIG. 1. The control shaft 4 carries thereon a switching cam 5 within the housing 1. The switching cam 5 has a cam lobe 5a to operate a microswitch (not shown) to turn on or off a lamp 1a for the lock stitching mechanism, and a cam lobe 5b to operate another microswitch (not shown) to turn on or off a lamp 2a for the overlock stitching mechanism. The switching cam 5 is connected at the cam lobe 5b thereof to one end of an arm 7 by means of a rod 6. The arm 7 is at the other end thereof turnably mounted on a pivot 11a of a support 11 secured to a bracket 19, and is maintained there by a washer 12 together with another arm 8, which is connected to the arm 7 by a screw 9 as shown in FIG. 7. The arm 8 has operating parts 8a, 8b formed at one end and the intermediate thereof respectively for acting on three levers 13, 14, 16 each turnably mounted on a transverse shaft 19a of the bracket 19 as shown in FIG. 7. These 1evers 13, 14, 16 are prevented from axial displacement by a washer 18. A coi1 spring 15 is mounted on the transverse shaft 19a, and has a lower projection 15c and opposite end projections 15a, 15b. The lower projection 15c of the spring is stopped by a transverse pin 19b of the bracket 19, and the upper projection 15a of the spring 15 is pressed against the lever 13 and another upper projection 15b is pressed against the lever 14, thereby to normally bias the levers 13, 14 in the counterclockwise direction in FIG. 7. A tension spring 17 is at one end connected to a projected part 16d of the lever 16 and is at the other end anchored to a projection 19c of the bracket 19. Thus the lever 16 is normally biased in the counterclockwise direction in FIG. 7. The counterclockwise movement of the levers 13, 14 is limited by the operating parts 8a, 8b of the arm 8 respectively engaging a projection 13a of lever 13 and a projection 14a of the lever 14.
With reference to FIG. 8, a first stop cam 20 is turnably mounted on an upper drive shaft 38 as shown in FIG. 4 and has a predetermined number of axial grooves 20d formed in the peripheral flange thereof. These grooves 20d are selectively engagable by the end 13b of the lever 13. A second stop cam 32 is turnably mounted on an axial cylinder 31a of a belt wheel 31 which is rotatably mounted on a bushing 26 secured to one end of the upper drive shaft 38 by means of fastening screw 28. The stop cam 32 has a predetermined number of grooves 32d formed in the periphery thereof. These grooves 32d are selectively engageable by the end 14b of the lever 14. As shown in FIG. 7, the lever 16 has a pair of spaced ends 16a, 16b. The end 16a is designed to engage an axially extended flange part 20e of the stop cam 20, and the end 16b is designed to selectively engage the grooves 32d of the stop cam 32 when the thread winding operation is carried out. Normally the lever 16 is lifted up against the action of tension spring 17 by an arm of thread winding mechanism (not shown), so that the ends 16a, 16b may be spaced from the stop cams 20, 32.
A clutch mechanism of the sewing machine will now be explained in reference to FIGS. 4 and 8. The bushing 26 has a cut out as shown formed at the upper part thereof with the bottom faces 26a, 26b each sloping outwardly and downwardly from the center of the cutout. A pair of rollers 22, 23 are placed on the bottom faces 26a, 26b and spaced from each other by a leaf spring 24 until the rollers are pressed against opposite stops 20b, 20b formed in the cutout 20c of a tongue 20a axially extended from the stop cam 20 through a stop disk 25 which is secured to the bushing 26 by fastening screws 29 as shown in FIG. 5. As shown in FIG. 8, the stop cam 20 is connected to the bushing 26 by a pin 21 passing through an arcuate slot 20f formed therein and inserted into the hole of the bushing 26 through the stop member 25, so that the stop cam 20 may be turnable around the pin 21 within a predetermined angular range. The stop member 25 also functions to prevent the axial displacement of the belt wheel 31.
Another belt wheel 36 has an axial groove 36a of a predetermined width formed at the inner periphery thereof providing the faces outwardly lowering from the center thereof, and is rotatably mounted on the axial cylinder 31a of the belt wheel 31 to provide a chamber defined by a part of the outer face of axial cylinder 31a of the belt wheel 31 and the axial cutout 36a of the belt wheel 36. Another pair of rollers 33, 34 are placed in the chamber and are spaced from each other by a leaf spring 35 until the rollers are pressed against the opposite stops 32b formed in the cutout 32c of a tongue 32a axially extended from the stop cam 32 into the axial groove 36a of the belt wheel 36 as shown in FIG. 6. As shown, the axial cylinder 31a of the belt wheel 31 has a groove 31b into which part of a transmission disk is fitted which is formed with a lateral projection 37a on the outer side thereof and which acts as a stop preventing axial displacement of the belt wheel 36 as shown in FIG. 4. A hand wheel shaft 40 is rotably mounted in the bearing secured to the machine housing 2. The shaft 40 is coaxial with the upper drive shaft 38 and is at one end protruding out of the housing 2 for a hand wheel 41 to be secured thereto. The shaft 40 has also a disk 39 secured to the inner end thereof. The disk 39 is formed with a cutout 39a engaged by the lateral projection 37a of the transmission disk 37, so that the rotation of the belt wheel 31 may be transmitted to the hand wheel 41.
With the above mentioned structure of the invention, the operation is as follows: If the selecting dial 3 is rotated in the counterclockwise direction to position the indicating mark 3a in alignment with the mark LOCK STITCH on the housing 1 as shown in FIG. 1, the cam lobe 5a of the switching cam 5 operates the microswitch (not shown) to turn on the lamp 1a of the lock stitching mechanism (not shown). At the same time the arm 8 is turned in the counterclockwise direction around the pivot 11a by way of the rod 6 as is understood from FIG. 2. Therefore, the lever 13 is turned in the clockwise direction in FIG. 7 against the action of coil spring 15 while the lever 14 is turned in the counterclockwise direction by the action of spring 15. As a result, the end 13b of the lever is spaced from one of the grooves 20d of the stop cam 20 while the end 14b of the lever 14 engages one of the grooves 32d of the stop cam 32.
Therefore if the machine drive motor is driven, the belt wheel 31 is rotated in the counterclockwise direction by way of a belt 31A (in FIG. 3). Accordingly the roller 22 is displaced in the same direction to a position, as the belt wheel 31 is rotated, where it is pressed against the inner periphery of the belt wheel 31 and the face 26a of the bushing 26. Thus the rotation of the belt wheel 31 is transmitted to the bushing 26, and the upper drive shaft 38 is rotated, and the lock stitching mechanism is operated. On the other hand, since the stop cam 32 is detained by the lever 14, the rollers 33, 34 are held stationary in the positions where these rollers 33, 34 are spaced from the inner peripheral face 36a of the belt wheel 36. Therefore the rotation of the belt wheel 31 is not transmitted to the belt wheel 36 which is connected by way of a belt 32A, to the drive shaft of the overlock stitching mechanism (not shown). Thus the latter remains standstill.
In this case, the rotation of the belt wheel 31 is transmitted to the hand wheel 41 by way of the transmission disk 37. Therefore the upper or lower needle position may be adjusted by manual rotation of the hand wheel 41 when the machine drive motor is stopped. If the hand wheel 41 is rotated in the counterclockwise direction in FIG. 3, the upper drive shaft 38 is rotated in the same direction because the roller 22 is displaced to a position where it is pressed against the inner periphery of the belt wheel 31 and the face 26a of the bushing 26. On the other hand, if the hand wheel 41 is rotated in the opposite direction, the upper drive shaft 38 is rotated in the same direction because the roller 22 is displaced to a position where it is spaced from the inner periphery of the belt wheel 31 and the roller 23 is displaced to a position where it is pressed against the inner periphery of the belt wheel 31 and the face 26b of the bushing 26.
Then if the selecting dial 3 is rotated in the clockwise direction to position the indicating mark 3a in alignment with the mark OVERLOCK STITCH on the housing 1, the cam lobe 5a releases the microswitch (not shown) to turn off the lamp 1a for the lock stitching mechanism. On the other hand, the cam lobe 5b operates another microswitch to turn on the lamp 2a for the overlock stitching mechanism. At the same time, the arm 8 is turned in the clockwise direction in FIG. 2. Therefore, the lever 13 is released and turned in the counterclockwise direction in FIG. 7 by the action of spring 15. On the other hand, the lever 14 is turned in the clockwise direction against the action of spring 15. As a result, the end 13a of lever 13 engages one of the grooves 20d of the stop cam 20 while the end 14a of lever 14 is spaced from the stop cam 32. Therefore if the machine drive motor is driven, the belt wheel 31 is rotated in the counterclockwise direction by way of the belt 31A. The rotation of the belt wheel 31 is, however, not transmitted to the upper drive shaft 38 because the stop cam 20 is detained by the lever 13 and the rollers 22, 23 are held in the positions where these rollers are spaced from the inner periphery of the belt wheel 31. On the other hand, as the belt wheel 31 is rotated, the axial cylinder 31a carrying the rollers 33, 34 displaces the roller 33 to a position where it is pressed against the inner peripheral face 36a of the belt wheel 36 and the outer face of the axial cylinder 36a of belt wheel 36. Thus the rotation of the belt wheel 31 is transmitted to the belt wheel 36, and therefore the overlock stitching mechanism is operated while the lock stitching mechanism remains standstill. In this case, it is also possible, when the machine drive motor is stopped, to manually rotate the hand wheel 41 in either direction to adjust the upper or lower position of the needle of overlock stitching mechanism. The rotation of the hand wheel 41 is transmitted to the belt wheel 36 through the transmission disk 39, belt wheel 31, roller 33 or 34.
In reference to FIG. 1, a spool pin 42 is provided on the top of the sewing machine. The spool pin 42 is operated in association with a generally known thread winding mechanism (not shown). According to the invention, a bobbin is mounted on the spool pin 42, and the pin 42 is displaced toward the best wheel 31 around a separate pivot (not shown) so that the pin 42 may be rotated by the belt wheel 31 through a rotational member (not shown). Upon the displacement of the spool pin 42, the lever 16 is operatively released from the upper inoperative position. As a result, the lever 16 is turned in the counterclockwise direction by the action of the tension spring 17, and the spaced ends 16a, 16b engage the grooves 20d, 32d, of the stop cams 20, 32 respectively. Therefore if the machine drive motor is driven, the belt wheel 31 is rotated, thereby to rotate the spool pin 42. Thus a thread is wound around the bobbin on the spool pin 42. In this case, the rotation of the belt wheel 31 is not transmitted to the upper drive shaft 38 and to the belt wheel 36, and therefore the lock stitching and overlock stitching mechanisms remain stationary. | A selecting device for a double-function sewing machine having a single drive motor with the sewing machine including a first stitch forming mechanism to produce one type of stitch, a second stitch forming mechanism to produce another type of stitch, and a transmission for transmitting the rotation of the drive motor to the first and second stitch forming mechanism. The selecting device includes a first clutch operated into an operative position to contact the first stitch forming mechanism to a transmission and operated into an inoperative position to disconnect that mechanism from the transmission, and a second clutch operated into an operative position to connect the second stitch forming mechanism to the transmission and operated into an inoperative position to disconnect that mechanism from the transmission. A manually operated dial is mounted on the housing of the sewing machine, which is connected to a lever mechanism operated in one direction to hold the first mentioned clutch in the inoperative position and release the second clutch into the operative position. The lever mechanism is manually operated in another direction to hold the second clutch in the inoperative position and release the first clutch into the operative position. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to improved thermal stability of nanocomposites made from cellulosic materials in combination with clays such as smectic clays, hectorites and synthetic clays to produce materials that have a raised temperature at which degradation occurs and enhanced char yields.
DESCRIPTION OF THE PRIOR ART
[0002] The creation of nanocomposites from a combination of clays and different polymers, which are mixed when they are in the monomeric form, such as polyvinyl chloride, polypropylene, polymethyl methacrylate and polystyrene is known in the art. The prior art teaches that nylon 6-clay nanocomposites have enhanced tensile strength, an enhanced tensile modulus and a higher heat distortion temperature as compared to virgin nylon (Wang et al., Polymer Preprints 42(2), 842-843; 2001.
[0003] The creation of polypropylene/clay nanocomposites is taught by Ma et al. (Journal of Applied Polymer Science, Vol. 82, 3611-3617; 2001). With these composites the maximum decomposition temperature increased by 44° C. with the introduction of 10 wt. % clay.
[0004] Zeng et al. (Macromolecules 2001, 34, 4098-4103) discloses poly (methyl methacrylate) and polystyrene can substantially improve the dimensional stability of the polymer matrix in an exfoliated nanocomposite with uniform mesoscale clay dispersion.
[0005] Hiroyuki Matsumura and Wolfgang Glasser (Journal of Applied Polymer Science, Vol. 78, 2254-2261; 2000) have discovered that by reacting wood pulp fibers in a solvent medium that does not fully penetrate the fibers, and then hot-pressing the modified fibers at elevated temperature they were able to form a semi-transparent polymer sheet that is a nanocomposite of cellulose esters and unmodified cellulose.
[0006] Presently, no technique is available for the incorporation of clays in cellulose. A major drawback of cotton is its inherent ability to burn. Flame resistance can be imparted to cotton by conventional processes, but these finishes tend to be subject to loss after laundering and or problems with the fabric holding up to wear. There remains a need for the creation of alternate viable and cost-effective technologies to modify and make better industrial use of cotton fibers and cellulose in general which are available in abundance.
SUMMARY OF THE INVENTION
[0007] The present invention relates to the development of improved thermal stability of nanocomposites made from cellulosic materials in combination with smectic clays, hectorites or synthetic clays with a negative charge to produce materials that have increased degradation temperatures and enhanced char yields. Enhanced char yields are a significant identifier of nonflammable material. We have found that cellulose, including cotton, may be dissolved with a solvent and then intimately mixed with a clay at a molecular level. This mixing results in the creation of nanocomposites wherein the clay substituent mixes with the cellulose polymer and becomes incorporated into its matrix upon drying and removal of the solvent. The resultant nanocomposite materials may be used to produce fibers with enhanced flame retardant properties.
[0008] In accordance with this discovery, it is an object of the invention to provide a means for the creation of nanopolymers from cellulose in admixture with clays for the purpose of enhancing fire retardant properties.
[0009] Another object is to provide a means for coating materials using the created nanopolymers with enhanced properties for the purpose of fire retardance.
[0010] Other objects and advantages of the invention will become readily apparent from the ensuing description.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The present invention involves the creation of enhanced thermal stability properties for cellulosic materials such as fibers from bast e.g. flax, kozo and kenaf; wood fibers, leaf fibers e.g. sisal, henequen and abaca; and grass fibers (bamboo and rice straw, bagasse; cotton fiber) and previously processed cellulose fibers such as paper, newspaper or cardboard.
[0012] The invention relates to the creation of cellulose-based materials having an increased range of temperatures they will tolerate before undergoing degradation, and the ability of these materials to create high levels of char yield, which is used as a factor to determine level of flammability, as compared to untreated material.
[0013] It has been found that cellulosic materials treated with clays such as smectic clays, hectorites and synthetic clays produce materials that have increased degradation temperatures and enhanced char yields. The synthetic clays should have a negative surface charge and be regarded as hydrophobic colloids. Examples of usable synthetic clays are laponite, cloisite, flurohectorite, hydrotalcite and hematite. Preferred clays are clays of the smectic class. Types of smectic clays include aliettite, beidellite, hectorite, montmorillonite, nontronite, saponite, sauconite, stevensite, swinefordite, volkonskoite, yakhontovite, and zincsilite. The nanocomposites produced contain clay at a level of 0.5%-25% of the cellulose/clay composition, with a preferred range being 5%-15% and a most preferred range of 7%-10%.
[0014] We have found that cellulose, including cotton, may be totally or partially dissolved with a solvent and then have a clay, such as a smectic clay, hectorite or a synthetic clay mixed with it. Partial dissolution is defined as being a minimum of 50% by weight of the cellulose dissolved. This mixing results in the creation of nanocomposites wherein the clay substituent mixes with the cellulose polymer and becomes incorporated into its matrix upon drying and removal of the solvent. This forms the basis of creating fibers with enhanced flame retardant properties.
[heading-0015] Combination Parameters
[0016] The clay is required to be pretreated with an ammonium salt or acid that possesses alkylammonium cations or arylammonium cations such as first, second, third degree salts and quaternary compounds preferred compounds include dodecylamine, 12-aminododecanoic acid, or n-decyltrimethyl ammonium chloride alkyl ammonium salts. The resultant pretreated clay is suspended in water. Appropriate concentrations of the alkyl or aryl ammonium cations in water range from 0.005 M to 0.2 M for treating from 1 to 15 grams of clay. This pretreated clay suspension is then dried. The dried clay and the cellulosic material are then combined (with the order of combination not being critical) with a polar aprotic solvent such as 4-methylmorpholine-N-oxide (MMNO), cupriethylenediamine hydroxide, saturated zinc chloride, calcium thiocyanate and lithium chloride/dimethyl acetamide with the concentration of the solvent used being dependent upon the amount of cellulosic material to be dissolved. By way of example, for cotton cellulose a ratio of about 50 ml of MMNO per gram of cotton cellulose is preferred, while, for other cellulosics and alternate solvent systems the ratio may range from about 10 ml to about 500 ml per gram of material. The amount of clay combined with the cellulosic material should be sufficient to provide a dried cellulose/clay nanocomposite having between 0.5%-25% clay by weight, preferably between 5%-15%, and most preferably between 7%-10%.
[0017] This cellulose/clay/solvent mixture typically is then heated and refluxed at a temperature ranging from about 100° C. to 150° C. until a suitable amount of the cellulose material is dissolved and the clay is suspended. Approximately 1 hour to 3 hours after reflux is initiated the cellulosic material should be dissolved. If less than total dissolution of the cellulose is necessary then the amount of time involved in this step can be reduced accordingly. Cellulosic fibers from cotton take the greatest amount of time to dissolve due to the nature of its highly crystalline structure and its inherently high molecular weight. Cellulosic material from sources other than cotton fiber will dissolve more readily because of their lacking either or both of these properties. The resultant viscous amber solution is then removed from heat and precipitated in acetonitrile or any other polar solvent that is miscible with the solvent system utilized. The cellulose/clay nanocomposite precipitate may then be dried and collected. The material is preferably filtered and washed in water. The determination of filter and wash parameters are within the skill of the ordinary artisan.
[0018] The material is preferably washed and filtered 1 to 5 times, preferably 2-3 times. The cellulosic material is collected and dried under conditions that will not degrade the material so as to make it unusable. Temperatures up to the degradation temperature of cellulose are usable, but temperatures under 175° C. are preferred.
[0019] The process of the invention does not require that the clay and the cellulose be added to the solvent solution in a particular sequence. Thus, the order of combination described above can be reversed or carried out simultaneously by whatever means is available to the skilled artisan.
EXAMPLE 1
[0020] Cotton nanocomposites containing 0%-15% montmorillonite clay as filler material were prepared in batches of 1-2 grams of material according to the following procedures. Montmorrillonite K10 clay (Aldrich Chemical Company, Milwaukee, Wis.) was pretreated with the ammonium salt of dodecylamine according to a previously published procedure (K. Yano, A. Usuki, A. Okada, T. Kurauchi, O. Kamigaito; Journal Polymer Science, Part A: Polymeric Chemistry, 31, 2493, 1993). The pretreated clay was then used in the following procedure. Pretreated montmorrilonite clay was stirred rapidly in MMNO. After 30 minutes of stirring, cotton was added to the flask. The cotton/clay/MMNO solution was heated to reflux with continued stirring. Approximately 1 hour after reaching reflux, the cotton dissolved.
[0021] The viscous amber colored solution was removed from heat and reprecipitated into acetonitrile. The material was filtered and washed a second time in acetonitrile. After filtration, the material was washed in deionized water. After the final wash and filtration, the samples were collected as a powder and dried under vacuum at 120° C.
[0022] Thermogravimetric analyses (TGA) were performed on a TA Instruments Hi-Res TGA 2950. Samples were heated to 120° C. and held isothermally for 1 hour to normalize for moisture content. After air-cooling, scans were run from 40° C. to 600° C. at a heating of 10° C./min. Differential scanning calorimetry (DSC) was performed on a Mettler Toledo DSC 821. Thermal analysis results are shown in Table 1.
TABLE 1 Sample (wt % clay) T dec (° C.) Char yield (%) 0 326 3 1 327 8 2 331 12 3 327 13 7 327 28 10 321 30 15 316 34
EXAMPLE 2
[0023] Following the protocols of Example 1, nanocomposite formulations were prepared using kenaf, ramie, and wood pulp as the sources of cellulose. Pretreated montmorillonite clay or cloisite clay (a natural montmorillonite modified with a quaternary ammonium salt) (Southern Clay Products, Inc., Gonzales, Tex.) was used as the filler material. The cellulosic fibers were soaked in MMNO prior to heating to allow wetting of the fiber by the solvent. Thermal analysis results are presented in Table 2.
TABLE 2 T dec (° C.) Char yield (%) Cotton control 282 3 montmorillonite 327 28 cloisite 311 23 Ramie control 290 16 montmorillonite 335 32 cloisite 313 27 Kenaf control 283 12 montmorillonite 321 25 cloisite 305 22 Wood control 284 13 montmorillonite 313 25 cloisite 300 21
EXAMPLE 3
[0024] A nanocomposite formulation of 93% cotton and 7% montmorillonite clay was prepared. The mixture was stirred in an open container with heat until cellulose dissolution occurred. Using an automated syringe pump (Pump model 210, KD Scientific, New Hope, Pa.) the viscous dope was extruded from syringes through an 18½ M gauge needle at pump speeds varying from 1 mL/min to 10 mL/min. The fibers were spun into an open bath of either acetonitrile or water.
[0025] The coagulated fibers were collected manually and washed with water. Both solvents resulted in the removal of MMNO to allow coagulation of the regenerated cellulose and produced nanocomposites in the form of fibers or films. These resultant fibers and films were then dried. The materials were then tested for thermal properties. Thermal decomposition temperature for the materials was 333° C. and the char yield was 25%. These results are comparable to those obtained from cotton nanocomposites of similar formulation produced in Examples 1 and 2.
[0026] It is understood that the foregoing detailed description is given merely by way of illustration and that modifications and variations may be made therein without departing from the spirit and scope of the invention. For example, choice of specific components, their relative proportion and degree of reaction may be readily determined by those skilled in the art without undue experimentation using the teachings hereof. | This invention relates to a process of forming a nanocomposite of cellulose with a clay material that is used as the nanofiller material. The nanocomposites show significant improvements in thermal properties when compared to unbleached cotton and cotton processed under conditions for nanocomposite preparation. The degradation temperature of these nanocomposites is significantly increased over that of unbleached cotton. | 3 |
CROSS-REFERENCE TO PRIOR APPLICATION
This application relates to and claims priority from Japanese Patent Application No. 2005-087895, filed on Mar. 25, 2005 the entire disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for managing an access path, and more particularly to a management of an access path in a multi-path system that accesses a storage device by means of plural access paths in a storage area network (SAN).
The popularization of the Internet and transformation of data into multimedia allow the storage capacity of a storage device used in enterprises or the like to increase. An SAN is established for an enormous quantity of data that rapidly increases. In the SAN, plural host computers and a large-capacity data storage device, in particular, a disk array are connected to each other through fiber channels or the like, to thereby realize data sharing and high-speed accessing.
Plural adaptors for connection to the SAN such as host bus adaptors (HBA) and channel adaptors (hereinafter referred to as “CHA”), and plural devices used for connection with fiber channel switches (hereinafter merely referred to as “switches”) and hubs exist between the host computers and the storage device. The respective devices are so connected as to ensure plural paths (hereinafter referred to as “physical paths”) assuming a defect. Under the circumstances, the connection relationships become remarkably complicated.
Also, in the data storage device such as the disk array, it is possible that a storage area that is made up of plural physical disks is shared to plural logical volumes (hereinafter referred to as “logical volumes”), and then released to a specific host computer. A path (hereinafter referred to as “access path”) for accessing to the logical volume from the host computer is set from options of the abovementioned plural physical paths. There has been used a technique by which plural access paths are set with respect to one logical volume, and one access path is switched over to another access path at the time of a defect to continue access operation, or the plural access paths are used at the same time to disperse an access load (hereinafter referred to as “multi-path management”).
For example, Japanese Published Unexamined Patent Application No. 2000-330924 discloses that the access load on the storage device is appropriately dispersed to the plural access paths in the technique of the above type.
SUMMARY OF THE INVENTION
However, the number of physical paths and the number of access paths which are to be managed increase under the environments where the storage device is shared to the plural host computers. In addition, it is difficult to grasp the influences of the hosts and applications on each other and form an appropriate access path under the large-scale environments where managers of plural host computers (or plural groups of host computers) and plural applications (hereinafter referred to as “AP”) exist.
In the case where a defect occurs in the conventional multi-path management, all of the access paths that suffer from the defect are switched to other access paths. For that reason, there is the possibility that IO traffic on the SAN is greatly changed, and the access paths that have not yet been effected up to now are concentrated on a specific adaptor or switch. As a result, there arises such a problem that a time required for IO associated with a specific AP becomes long, and the operation of significant AP slows down. As described above, it is difficult to grasp the influences of the hosts and applications on each other and again form an access path such that the operation of significant AP does not slow on the large-scale SAN.
An object of the present invention is to provide a method and an apparatus for managing an access path, which grasp in advance a portion that may cause a bottleneck due to the concentration of traffics in a multi-path system, and notify an operation manager of that portion.
More specifically, an object of the present invention is to provide the management of an access path which aggregates information on switchable access paths, and calculate a change in the traffic in the case where the access path is switched to another access path due to the occurrence of a defect of a device such as the respective adaptors or switches, to thereby detect in advance a portion that may cause a bottleneck due to the concentration of traffic at the time of occurrence of the defect and to notify an operation manager of that portion.
According to one aspect of the present invention, there is provided a method for managing an access path in a storage network system that forms multiple paths between a large-capacity data storage device and a host computer that employs the data storage device, and transfers data by means of a selected path, the method including the steps: selecting a second access path that can be used as a replacement of a first access path that connects the data storage device and the host computer; calculating the quantity of traffic on the first access path which is associated with a device disposed on the first access path; calculating a variation of the quantity of traffic on the second access path which is associated with a device disposed on the second access path taking the calculated quantity of traffic into consideration; determining whether the device on the second access path causes a bottleneck or not, according to a calculated value of the variation of traffic on the second access path; and notifying the outside of a determination result.
In a preferable example, the first and second access paths include plural ports of the data storage device, plural adaptors of the host computer, and switches that switch over connection relationships between the ports and the adaptors. Information on identifiers indicative of those connection relationships is displayed on a display device in order to notify a manager of the information as path information of the bottleneck.
Also, it is preferable to reduce a value of the quantity of traffic on the first access path, and add the reduced value to the quantity of traffic associated with the device on the second access path, to calculate the variation of the quantity of traffic in the respective devices on the second access path.
Further, in one example, in the case where plural second access paths exist with respect to the first access path, a value obtained by dividing the calculated value of the traffic quantity on the first access path by the number of second access paths is equally added in calculation of the variation of the traffic quantity in the respective devices on the second access path.
Also, in an example of the determination of the bottleneck, in the case where the calculated value of the variation of traffic is larger than 0, it is determined that there is a bottleneck.
Also, in a preferable example, plural access paths for accessing at least one logical volume formed in the data storage device from the host computer are managed, and a traffic information table that stores the calculated quantity of traffic is prepared with respect to the device on the selected second access path and then stored in a storage device of a server that manages the access path.
In addition, in a preferable example, an access path information table that stores information indicative of a host computer path adaptor of the host computer, a port of the data storage device, an identifier of the logical volume, and an application program stored in the logical volume, which exist on the access path, is stored in the storage device of the server that manages the access path in correspondence with an ID of the access path.
Then, the determination result is notified to the application program registered in the table and the associated manager of with reference to the access path information table.
According to the present invention, there is provided an access path management program that is executed in a storage network system that can connect a host computer that processes information with a storage device that stores the information therein via multiple paths, the program including the steps of: inputting a first device that constitutes a storage network; acquiring a second device where access paths are concentrated and the traffic is increased in the case where all of the access paths that pass through the first device are switched over to other access paths through a multi-path managing process; and transferring information related to the acquired second device to display the information on a display device.
Also, in one example, the access path management program further includes the steps of: acquiring an access path that passes through the second device; and displaying the information on the access path on the display device.
According to the present invention, there is provided a management server that manages an access path between a large-capacity data storage device and a host computer that employs the data storage device in a storage network system that forms multiple paths between the data storage device and the host computer to transfer data by means of a selected path, the management server including: a main memory that stores an access path integration management program for integrally managing the access path, and holds temporal data associated with execution of the program; a processing device that executes the access path integration management program; and a display device that displays a state in which the access path integration management program is executed, wherein the processing device includes means for selecting a second access path that can be used as a substitute of a first access path that connects the data storage device with the host computer by execution of the access path integration management program; means for calculating the quantity of traffic of the first access path which is associated with a device on the first access path; means for calculating a variation of traffic quantity of the second access path which is associated with a device on the second access path taking the calculated quantity of traffic into consideration; means for determining whether the device on the second access path is a bottleneck or not, according to the calculated variation of traffic of the second access path; and means for notifying the outside of the determination result.
In a preferred example, the management server includes a storage device that stores a table that stores structural device information related to a device that constitutes an SAN collected from the host computer therein, a table that stores access path information related to a device or port which constitutes the access path, a table that stores the traffic information related to the traffic of the device and the port on the access port, and a table that stores traffic calculation information indicative of a calculated value related to the variation of traffic with respect to the device on the access path which is obtained by the execution of the access path integration management program.
Also, preferably, the management server further includes: a storage device that stores an access path information table which stores information indicative of a host bus adaptor of the host computer, a port of the data storage device, an identifier of a logical volume, and an application program stored in the logical volume, wherein the determination result is notified to the application program registered in the table and the related manager with reference to the access path information table.
According to the present invention, information on the access path which can be switched over at the time of occurrence of a defect which is held by multi-path management software is collected. In the case where the access path is switched over due to a defect of a device on the access path, a variation in the traffic is calculated, thereby making it possible to grasp a portion that may become a bottleneck by concentration of the traffic in advance. Then, the information related on the bottleneck is notified a system manager of, thereby making it possible to conduct a countermeasure to a delay of the processing operation of AP at the time of occurrence of the defect.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing an access path management system that is applied to the SAN according to an embodiment of the present invention;
FIG. 2 is a structural diagram showing a management server in the access path management system according to the embodiment;
FIG. 3 is a flowchart for explaining an access path integration management and control system process according to the embodiment;
FIG. 4 is a diagram showing an example of a table of traffic calculation information according to the embodiment;
FIG. 5 is a diagram showing an example of a table of traffic information according to the embodiment;
FIG. 6 is a diagram showing an example of a table of access path information according to the embodiment;
FIG. 7 is a diagram showing an example of a table of SAN structural device information according to the embodiment;
FIG. 8 is a flowchart for explaining a switch path acquiring process according to the embodiment;
FIG. 9 is a flowchart for explaining a traffic calculating process according to the embodiment;
FIG. 10 is a flowchart for explaining a bottleneck determining process according to the embodiment;
FIG. 11 is a flowchart for explaining a performance deterioration path calculating process according to the embodiment;
FIG. 12 is a diagram showing a structural example of an SAN system;
FIG. 13 is a diagram showing an example of access paths under a multi-path management;
FIG. 14 is a diagram showing a principle of an access path managing method according to the embodiment; and
FIG. 15 is a diagram showing an example of a table of a replacement access path identifier list according to the embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, a description will be given in more detail of an embodiment of the present invention with reference of the accompanying drawings.
FIG. 12 shows a structural example of an SAN system according to an embodiment of the present invention.
A host computer 13 is connected to a port of a connection device such as a switch 1202 or a hub through an HBA 1201 . The switch 1202 is connected to a channel adaptor (hereinafter referred to as “CHA”) 1203 of a large-capacity data storage device 14 such as a disk array and a port 1204 such as a port controller. The large-capacity data storage device 14 is made up of plural physical disks 1205 , and a logical volume 1206 that is a logical access unit is formed on each of the plural physical disks 1205 , and the plural logical volumes are released to the host computer.
FIG. 13 is a diagram showing an example of an access path under a multi-path management that is applied to the SAN system of FIG. 12 . For facilitation of viewing, physical paths, storage devices and switches which are unnecessary for description are omitted from FIG. 13 . Also, a pair of access paths are shown with respect to one logical volume 1 ( 1206 b ) as the logical volume, but in general, plural access paths exist with respect to plural logical volumes, and the multi-path management is applied to those paths.
The access path is set by a management tool of the storage device 14 or SAN management software. First, an identifier of a specific logical volume 1206 and a port 1204 of the storage device 14 are allocated. In an example shown in FIG. 13 , the logical volume 1 ( 1206 b ) is allocated to a port 1 ( 1204 a ) and a port 4 ( 1204 d ), respectively. Also, the port 1 ( 1204 a ) side is released to a port HBA 1 ( 1201 a ) of the host computer 1 ( 13 a ), and the port 4 ( 1204 d ) side is released to a port HBA 2 ( 1201 b ) of the host computer 1 ( 13 a ) by setting the access control, respectively. A world wide name (WWN) is allocated to the protocol of a fiber channel as a unique identifier, and used as a unique identifier.
In the example shown in FIG. 13 , the logical volume 1 ( 1206 b ) has two access paths consisting of an access path that passes through the HBA 1 ( 1201 a ) of the host computer 1 ( 13 a ), the switch 1 ( 1202 a ) and the port 1 ( 1204 a ) of the storage device ( 14 a ), and an access path that passes through the HBA 2 ( 1201 b ) of the host computer 1 ( 13 a ), the switch 2 ( 1202 b ) and the port 4 ( 1204 d ) of the storage device ( 14 a ). The multi-path management 113 is capable of accessing those plural access paths as a volume 1301 that is recognized on one host computer.
In the examples shown in FIGS. 13 and 14 , the access path (hereinafter referred to as “active access path”) that is in use online is indicated by a bold line, and an access path (hereinafter referred to as “replacement access path”) of offline which is a substitute candidate is indicated by a dotted line.
In the case where there occurs a defect of the active access path such as a defect of the HBA or the CHA, a defect of the switch or a defect of a cable, the active access path is switched to one substitute access path among the substitute access paths by priorities that are determined by the multi-path management. The priorities are variously determined, for example, in the order of performance of the CHA that constitutes the access path, or in the smaller order of ID. In any case, it is necessary to uniquely determine the substitute access path.
FIG. 14 is a diagram showing a principle of an access path managing method according to an embodiment of the present invention.
A change in the traffic in the case where the access path is switched to another access path due to the occurrence of a defect that may occur in the respective ports or switches is grasped in advance. With this operation, a bottleneck portion at the time of occurrence of the defect is detected in advance, and a problem on the present substitute access path setting is notified to a system manager such as the host computer or the AP.
First, a location of a device that constitutes the SAN at which a defect occurs is assumed. A device such as an HBA, a CHA or a switch will be described as the location of a defect. However, it is easy to apply this embodiment to another location of a defect as with the cable if the multi-path management can acquire the structure of a physical path. Also, in the case where the multi-path management acquires only the structure of the HBA and CHA, it is possible to apply this embodiment to access paths other than the switch.
In the example shown in FIG. 14 , in the case where it is assumed that a defect occurs in the CHA 1 ( 1203 a ), it is grasped where any problem occurs. Then, the same investigation is conducted on other CHA (for example, 1203 b ), HBA (for example, 1201 a , 1201 b , 1201 c , or 1201 d ), and switch (for example, 1202 a or 1202 b ) through a loop process, thereby making it possible to investigate a problem on the substitute access path setting in the present SAN structure. Also, in the case where a defect occurs at the plural portions, this embodiment is sequentially applied to the respective portions, and the following process is applied to the access path in which failure occurs at the plural portions only once, thereby making easy to readily apply the present invention.
Subsequently, in the case where failure occurs at the assumed defective portion, an access path to be switched is extracted. Information on a substitute access path for the access path that passes through the assumed defective portion is acquired. In FIGS. 13 and 14 , only one access path that passes through the defective portion is shown for simplification. However, there exist plural defective portions, and in this case, the above loop process is sequentially applied.
It is assumed that the defective portion is a CHA 1 ( 1203 a ) in the case where a failure occurs, an access path that passes through the defective portion, that is, a failure occurs in the access path that passes through the HBA 1 ( 1201 a ) of the host computer 1 ( 13 a ), the switch 1 ( 1202 a ), and the port 1 ( 1204 a ) of the storage device ( 14 a ), and the access path is switched to another access path. As described above, a substitute access path is selected in the order of priority that is determined by the multi-path management. In the example of FIG. 14 , the access path is switched to an access path that passes through the HBA 2 ( 1201 b ) of the host computer 1 ( 13 a ), the switch 2 ( 1202 b ), and the port 4 ( 1204 d ) of the storage device 14 a , A state of the use access pass is represented by a bold line.
Subsequently, a change in the traffic to the switch of the access path is grasped. Because the access path that passes through the defective portion does not become the use access path, the traffic of that access path is reduced from the device on the access path. Also, it is assumed that the abovementioned reduced traffic is increased in the device on the access path with respect to the access path that switches from the substitute access path to the use access path.
Therefore, each of the respective devices adds an increment and a decrement of the traffic to the port of the device, and calculates a change in the quantity of traffic in the case where the access path is switched. In this example, as a method of calculating the traffic that passes through the access path, there is a method in which the multi-path management manages performance information (for example, the number of IO) on the access path or the like, and then acquires the traffic from the multi-path management. Also, as a method other than the multi-path management, there is a method in which there exists software for acquiring the performance information, and statistic information on the access path or a volume 1401 is acquired according to a performance information acquirement command of the multi-path management or OS. In addition, there is a method in which statistic information on the volume 1401 is acquired from a statistic information tool of AP. Also, the IO traffic to be used may be a certain instantaneous value or calculated by a statistic manner of the maximum value or an average value in a given period of time.
FIGS. 13 and 14 show an example in which the access path is switched when a failure occurs. In the case of using the function of the multi-path management 113 that disperses the traffic in the plural access paths, the traffic as much as a quantity calculated to be reduced due to the failure of one access path is equally shared to the remaining access paths and added, thereby making possible to calculate an increase. In the case where the multi-path management 113 uses a specific dispersing method, the increase may be calculated according to the method.
Finally, information on bottleneck of the access path, the device, the volume or the AP which become the bottleneck is notified to a system manager who uses a portion which is judged to be the bottleneck with a rapid increase in the traffic on a specific device due to a change in the traffic.
As a method of judging the bottleneck, there are proposed a method of merely determining whether the traffic is increased or not, a method of determining whether the traffic is rapidly increased to twice or three times or not, a method of registering the allowable amount of the traffic due to the specification of the device in advance and judging whether the actual traffic amount exceeds the allowable amount or not, and a method of calculating the allowable amount of the traffic of the device by an actual measurement and judging whether the actual traffic amount exceeds the allowable amount or not. Also, there is proposed a method of inputting the amount of traffic by a function defined by a user and defining conditions using a calculating formula for determining whether there is a bottleneck or not, and using the conditions for judgment of the bottleneck.
Then, an access path that passes through a portion which is judged as the bottleneck is extracted. In the example of FIG. 14 , in the case where an HBA 2 ( 1201 b ) is judged as the bottleneck, an access path that passes through the HBA 2 ( 1201 b ), a switch 2 ( 1202 b ), and a port 3 ( 1204 c ) of the storage device ( 14 a ) to the volume 2 ( 1401 b ) of the host computer 1 ( 13 a ) passes through the HBA 2 ( 1201 b ), and the access path is influenced by the HBA 2 ( 1201 b ). A manager of the volume 2 ( 1401 b ) of the host computer 1 ( 13 a ) or the system (for example, AP 2 ) using the volume 2 ( 1401 b ) is notified of information on the bottleneck such as information on a device which is an assumed defective portion, a portion that is judged as the bottleneck and AP influenced by the portion, or a volume that stores the data. It is needless to say that plural portions that are judged as the bottleneck may exist.
In the example of FIG. 14 , in the case where a port 4 ( 1204 d ) of a CHA 2 ( 1203 b ) is judged as the bottleneck, an access path that passes through an HBA 3 ( 1201 c ), a switch 2 ( 1202 b ) and a port 4 ( 1204 d ) of the storage device ( 14 a ) to a volume 1 ( 1401 c ) of a host computer 2 ( 13 b ) passes through the port 4 ( 1204 d ), and the access path is influenced by the port 4 ( 1204 d ). A manager of the volume 1 ( 1401 c ) of the host computer 2 ( 13 b ) or AP 3 who uses the volume 1 ( 1401 c ) is notified of information on the bottleneck such as information on a device that is an assumed defective portion, a portion that is judged as the bottleneck or an AP that is influenced by the bottleneck, or a volume that stores the data. The AP, the volume for storing the data of the AP, the identifier of the manager, a method of notifying the manager may be registered in a database by software for management of an access path and then managed, or may be used in association with information on an application server or a directory server. As the notifying method, there can be applied a generally employed method such as a method of displaying the information on a display device of the related manager, a method of sending the information by e-mail, or a method of recording the information in a log and making the manager refer to the information timely.
FIG. 1 is a diagram showing an access path management system that is applied to an SAN system according to an embodiment of the present invention.
The SAN system ( FIG. 12 ) is made up of plural host computers 13 that are connected to the SAN, and plural large-capacity data storage devices 14 . In this embodiment, the host computers 13 are connected to a management server 11 that manages the access path in the SAN system through a network. Also, the management server 11 has a storage device 12 that stores information for managing the access path.
The management server 11 executes an access path integration management program 100 for managing the access path of the SAN system in an integrating manner. The access path management program 100 includes the respective processing functions of a switching path acquiring process 102 that switches an access path to be switched over from the assumed defective portion, a traffic calculating process 103 that calculates a change in the traffic with respect to the switching of the access path, a bottleneck determining process 104 that determines a bottleneck according the calculation of the change in the traffic, a performance deterioration path calculating process 105 that extracts an access path which is calculated to be deteriorated in the performance by passing therethrough with respect to a portion that is determined as the bottleneck, and an access path integration management and control process 101 that controls the respective processes and sequentially applies those processes to the respectively assumed defective portions.
On the other hand, each of the host computers 13 has a host computer information collecting program 112 having a function for acquiring the performance information of the host computer and a function for collecting the host computer information due to the SAN management software, and a multi-path management program 113 for conducting the management of the multi-paths and the switching control shown in FIGS. 12 and 13 . The multi-path management program 113 is software that conducts the general multi-path management which switches over the access path at the time of a defect or disperses a load of access by using plural access paths at the same time.
The storage device 12 of the management server 11 stores a structural device information 116 related to devices that constitute the SAN which is collected from a multi-path management program 113 or a host computer information collecting program 112 of each of the host computers 13 , an access path information 115 related to the devices and the ports which constitutes the access path, and a traffic information 114 related to the traffic of the devices and the ports on the access path. Also, the storage device 12 stores traffic calculation information 106 indicative of a calculation value related to a variation in the traffic with respect to each of the devices on the access path, the value obtained as a result of execution of the access path management according to this embodiment.
The access path management program 100 executes the management of the access path by using those information 114 to 116 which are stored in the storage device 12 . The traffic calculating process 103 calculates a traffic calculation information indicative a calculation value related to the variation in the traffic with respect to each of the devices on the access path. The bottleneck determining process 104 calculates and detects a portion that becomes the bottleneck according to the calculation result made by the traffic calculation process 103 .
FIG. 2 is a structural diagram showing the management server 11 according to the embodiment of the present invention. The management server 11 is constituted as a computation system having a display device 201 , an input device 202 , a central processing unit (CPU) 203 , a portable medium drive 204 , a main memory 205 , a storage device 12 such as a disk drive, and a communication control device 207 , which are connected to a system bus 208 .
The display device 201 displays the executed status of the database management system program. The input device 202 is used for inputting various information. In this embodiment, the input device 202 is further used to input a command that is instructed in the execution of the access path management program. The central processing unit 203 executes various programs that constitute the access path management according to this embodiment. The portable medium drive 204 is used for writing data on the portable medium 209 such as a flexible disk, a magnetic optical disk or a write once optical disk.
The main memory 205 holds the above various programs, and temporal data associated with the execution of program. The storage device 12 stores the above various information therein. The communication control device 207 communicates with the network 210 . In this embodiment, the communication control device 207 particularly conducts communications such as a request for collecting information on the access path or the traffic from each of the host computers 13 , and the exchange of data.
The main memory 205 ensures a work area 212 , and also stores program such as a system program 211 and an access integration management program 100 . The work area 212 is used for storing data that is temporally required in the execution of the program. The system program 211 provides a basic processing function for executing various programs including the access path integration management program 100 such as input and output of data with respect to a peripheral device. In this embodiment, the main memory 205 stores therein the access integration management program 100 including the access path integration management and control process 101 , the switching path acquiring process 102 , the traffic calculating process 103 , the bottleneck determining process 104 , and the performance deterioration path calculating process 105 . However, in another example in which the above respective processing functions are constituted as individual programs, respectively, the program for each of those processing functions is stored in the main memory 205 . Those programs are taken in the main memory 205 from the portable medium 209 through the drive 204 , or from the network 210 through the communication control device 207 .
In this embodiment, the traffic calculation information 106 , the traffic information 114 , the access path information 115 , and the SAN structural device information 116 are stored in the storage device 12 . However, the present invention is not limited to this structure. For example, it is possible that the information is collected from the host computer 13 as needed, and then temporally stored in the memory 205 .
FIG. 3 is a flowchart showing the processing of the access path integration management and control system process 101 according to an embodiment of the present invention.
First, the access path integration management and control process 101 according to this embodiment will be totally described with reference to FIG. 3 . Thereafter, the respective characteristic processing will be described in more detail with reference to FIGS. 8 to 11 .
In FIG. 3 , an identifier of the device that can form a part of the access path is acquired from the information 116 of the device that constitutes the SAN as the assumed defective portion (S 301 ). Then, the switching path acquiring process 102 that extracts an access path to be switched over from the assumed defective portion is executed with the acquired identifier of the device as an input (parameter) (S 302 ). Then, the traffic calculating process 103 that calculates a change in the traffic is executed with the information 311 on the switching path which is extracted from the switching path acquiring process 102 as an input (S 303 ). Then, the bottleneck determining process 104 that determines a portion that is calculated as the bottleneck is executed with the information 106 that records the calculated value of the variation in the traffic with respect to the respective devices on the access path which is prepared by the traffic calculating process 103 as an input (S 304 ).
Subsequently, the performance deterioration path calculating process 105 that extracts the access path that is calculated to be deteriorated in the performance is executed with the information 312 on the device that is calculated as the bottleneck which is detected by the bottleneck determining process 104 as an input (S 305 ). Finally, the information 313 on the access path that is calculated to be deteriorated in the performance which is calculated by the bottleneck determining process 104 is used, and the information on the bottleneck such as the device that is the assumed defective portion, the access path that becomes the bottleneck, the volume of the access path, the AP that uses the volume, and the device that becomes the bottleneck is notified to the system manager (S 306 ). As the notifying method, the information may be display on the display device of the manager or transmitted via e-mail as described above.
In the subsequent processing, the above process is repeated on the device that can form a part of the access path (S 307 ).
FIG. 4 is an example showing a table of the traffic calculation information 106 according to the embodiment.
The traffic calculation information 106 is information that stores the quantity of traffic which is changed according to the switching of the access path with respect to the device and the port which constitute the access path. The traffic calculation information 106 includes identifiers 401 of the devices, device identifications 402 , identifiers 403 of the ports, and variations 404 in the traffic.
In this example, the identifiers 401 of the device are information for identifying the devices on the access path, and the device identifications 402 indicate those devices. Also, the identifiers 403 of the ports are information for identifying the ports of those devices. The traffic variations 404 represent an increase and decrease (+and −) of the traffic quantity after calculation, and its unit is megabit/sec (Mbps) or byte/sec which are used for the unit of a data transfer speed.
In the example of FIG. 4 , a device or port which causes the variation in the traffic quantity is applied, but the initial value of the variation may be held to 0 or NULL value with respect to all of the devices or ports. In the example of FIG. 4 , different types of devices such as an HBA or a CHA are collected in one table so as to be distinguishable according to the identification 402 of the devices. Alternatively, the devices of the same type may be collected in each of the different tables and managed. In addition, in the example of FIG. 4 , the relative variation 404 of the traffic is stored in the table. Alternatively, it is possible that the variation 404 of the traffic is held as an absolute quantity such as the calculated values of the traffic quantity before switching the access path and the traffic quantity after switching the access path in advance, and the quantity to be varied is obtained later.
FIG. 5 shows an example of a table of the traffic information 114 in the embodiment.
The traffic information 114 is information on the traffic of the devices or the ports on the access path which is acquired from the host computer information collecting function 112 by the multi-path management software 113 of the respective host computers 13 or the performance information acquiring software. The traffic information 114 includes identifiers 501 of the devices, types of the devices 502 , identifiers 503 of the ports, and the quantity of traffic 504 . As the traffic quantity 504 , the quantity of data which can be transferred per one second such as megabit/sec (Mbps) or byte/sec which are used in the unit of the data transfer speed of an HBA, a CHA or a cable can be used.
In this example, the traffic quantity 504 indicates the calculated quantity of traffic before switching. The traffic quantity 504 may be a certain instantaneous value or the maximum value or an average value in a given period of time which is calculated by the statistic manner. Also, in the example of FIG. 5 , the device and the port having the variation of the traffic quantity are shown as in FIG. 4 . However, the quantity of traffic in all of the devices and ports may be acquired and held.
FIG. 6 shows an example of a table of the access path information 115 according to the embodiment.
The access path information 115 is information on the access path which is acquired from the host computer information collecting function 112 by the multi-path management software 113 of the respective host computers 13 or the software for acquiring the performance information.
The access path information 115 includes identifiers 601 of the access paths, identifiers 602 of the host computers, identifiers 603 of the logical volumes 1206 , AP 604 that is stored in the logical volume, information 610 on the AP operating manager, identifiers 605 of the ports 1204 of CHA of the storage device 14 , identifiers 606 of the ports 1201 of HBA of the releasing host computers 13 , a switch port list 607 , a priority 608 based on the order of priority which is determined by the multi-path management 113 , and the quantity of traffic 609 . In this embodiment, the access path information 115 includes the switch port list 607 that represents the information on the switches, from which the information on the switch 1202 can be acquired by the multi-path management 113 of the host computer.
In the example of FIG. 6 , the information on the structure of the access path and the information on the traffic are collected in one table. However, the information may be managed in different tables, respectively. For example, information on the relationships of the volume 603 , the AP 604 and the operating manager 610 may be in another table format.
Also, in the example of FIG. 6 , the priority 608 is indicated. However, the priority 608 may be eliminated in the case where the order of priority made by the multi-path management 113 can be determined according to other information such as the smaller order of the identifiers 605 of the ports of CHA or the identifiers 606 of the ports of the HBA. Also, in the example of FIG. 6 , the identifiers of the CHA and the identifiers of the port are stored in one column, but may be held in the different columns.
Further, in the structure of the SAN where the switches 1202 are connected to each other and complicatedly weaved, there is a case in which the physical access path related to the switch is not uniquely determined. Even in this case, the concept of the present invention can be applied to this case by holding the plural switch port lists 607 in advance, and equally sharing the increased value of the traffic quantity to the respective physical access paths. As another method, in the case where the switch 1202 uses the control method of a specific access path, the increase may be calculated according to that method.
FIG. 7 shows an example of a table of the SAN structural device information 116 according to the embodiment.
The SAN structural device information 116 is information on the devices that constitute the SAN which is acquired from the host computer information collecting function 112 by the multi-path management software 113 of the respective host computers 13 or the SAN management software. The SAN structural device information 116 includes an identifier 703 of the port of a connecting device and an identifier 704 of the port of a connected device in association with a device identifier 701 and a device type 702 .
In the example of FIG. 7 , the devices 701 of the different type such as HBA or CHA are collected in one table so as to be distinguishable according to the type 702 of the device. However, the devices of the same types may be managed in each of different tables, respectively.
Subsequently, a description will be given in more detail of the access path integration management and control process shown in FIG. 3 with reference to FIGS. 8 to 11 .
FIG. 8 is a flowchart showing a switching path acquiring process 102 according to the embodiment. As shown in FIG. 3 , the switching path acquiring process is executed with the identifier of a device that is an assumed defective portion as an input (S 302 ). Since an access path that passes through the device which becomes an input is an access path to be switched, the information on a substitute access path as well as the access path to be switched is extracted from the information 115 on the access path.
First, the information 115 on the access path is sequentially retrieved (S 801 , S 817 ), and the identifier of the device that becomes an input is compared with the identifier of the device that constitutes the access path (S 802 , S 803 ). The comparison is conducted with reference to the information on the corresponding device such that the information 606 on the HBA is referred to when the device is the HBA, or the information 605 on the CHA is referred to when the device is the CHA. When the devices that constitute the access path include a device that is an input, that is, an assumed defective portion, since that device is an access path to be switched, the information 311 on the switching path is prepared and registered (S 804 ). Since there exist plural access paths that pass through the assumed defective portion and switch over, plural information on the switching path can be held with a list.
Subsequently, a substitute access path that becomes a switched access path with the acquired access path (P 1 ) is extracted by sequentially retrieving the information 115 on the access path (S 805 , S 816 ). In the case where the same volume 1206 communicates with the same host computer 13 through different access paths, those access paths become candidates. The access path (P 2 ) that coincides with both of the identifier 602 of the host computer and the identifier 603 of the volume is extracted (S 806 , S 807 ), and the access path that is applied as the switched access path is selected. First, if P 2 includes a device that is an input, that is, the assumed defective portion, since its access path is also defective and cannot be used, the access path is compared with the device that constitutes the access path, and removed (S 808 , S 809 ).
Subsequently, because there exist plural substitute access paths, the access path that is high in priority is extracted by comparing the priority. When there does not yet exist the list of the identifiers of the substitute access paths of the information 311 on the switching path (S 810 , S 811 ), and the access path is the substitute access path that has been first extracted, P 2 and the information on the priority are recorded in the switching path information 311 (S 814 , S 815 ).
On the other hand, in the case where the access path has been already registered in the list of the identifiers of the substitute access paths as the candidates to be switched (S 810 , S 811 ), the priorities are compared, and P 2 is removed if the priority of P 2 is lower (S 812 , S 813 ). When the priority of P 2 is higher, the information on P 2 and its priority is recorded in the switching path information 311 (S 814 , S 815 ). Also, in the case where there exist plural access paths having the same priority, plural access paths are registered in the list of the identifiers of the substitute access paths as the candidate to be dispersed as the plural access paths being dispersed and used, thereby making it possible to apply the access path to the dispersion. In this case, in a process of registering P 2 in the switching path information 311 (S 814 ), P 2 may be added in the list of the identifiers of the substitute access paths.
Also, in the case where all of the substitute access paths pass through the assumed defective portion, and there is no switching access path, nothing is recorded in the substitute access path identifier list of the switching path information 311 , and an initial value such as NULL remains in the substitute access path identifier list. In this case, as a problem that there is no switching access path, it is considered that the information on the access path is notified to a manager or an AP operator.
Subsequently, the processing operation of the traffic calculating process 103 will be described with reference to FIG. 9 .
As shown in FIG. 3 , the traffic calculating process is executed with the information 311 on the switching path which is extracted from the switching path acquiring process 102 as an input (S 302 ). The quantity of traffic is subtracted from the device and the port which pass through the access path (P 1 ) to be switched over to another access path, and the increased quantity of traffic is added to the device and the port which pass through the access path (P 2 ) to which the defective access path is to be switched over.
Since there exist plural access paths that pass through the assumed defective portion and are switched over, the respective switching path information is sequentially processed (S 901 , S 919 ).
First, the information on the access path P 1 which is to be switched over another access path is acquired from the access path information 115 (S 902 ). The identifiers of the device and the port which constitute the access path are sequentially acquired from the acquired information on the access path P 1 and then processed (S 903 , S 908 ). The information on a change in the traffic with respect to the acquired device and port is retrieved from the traffic calculation information 106 (S 904 ). In the case where there is no information on the acquired device and port, the information on the newly acquired device and port is added, and the initial value of the variation in the traffic is set to 0 (S 906 ). Then, the quantity of the traffic of the access path P 1 is subtracted from the variation in the traffic with respect to the acquired device and port (S 907 ).
Subsequently, the substitute access path is sequentially acquired from the substitute access path identifier list as the access pass to which the defective access pass is switched over (P 2 ), and then processed (S 909 , S 918 ). The information on the access path P 2 is acquired from the access path information 115 (S 910 ). The identifiers of the device and the port which constitute the access path are sequentially acquired from the acquired information on the access path P 2 , and then processed (S 911 , S 917 ). The information on the change in the traffic with respect to the acquired device and port is retrieved from the traffic calculation information 106 (S 912 ). In the case where there is no information on the acquired device and port, the information on the device and port which have been newly acquired is added, and the initial value of the variation in the traffic is set to 0 (S 914 ).
Subsequently, the increased quantity of traffic is calculated (S 915 ). As a calculating method, there is a method in which the traffic 608 that is calculated to be reduced due to the defect of one access path is equally divided by the number of the remaining access paths, for example, the number of substitute access path identifiers that have been recorded in the substitute access path identifier list, and then added, to thereby calculate the increased quantity. In this example, the substitute access path identifier list is stored in the storage device 12 and prepared in advance as shown in FIG. 15 .
As another calculating method, in the case where the multi-path management 113 uses a specific dispersing method, for example, such that the specific gravity of the faster device is increased, the increased quantity may be calculated according to the method. Then, the calculated quantity of traffic is added to the variation in the traffic of the acquired device and port (S 916 ).
Subsequently, the processing operation of the bottleneck determining process 104 will be described with reference to FIG. 10 .
As shown in FIG. 3 , the bottleneck determining process is executed with the traffic calculation information 106 indicative of the variation in the traffic with respect to the respective devices on the access path which is prepared by the traffic calculating process 103 as an input (S 303 ). It is determined whether the increased quantity of traffic becomes a bottleneck with respect to the device and port in which the traffic is changed. Since there generally exist plural devices and ports in which the traffic is changed, the respective data of the traffic calculation information 106 is sequentially processed (S 1001 , S 1006 ).
First, the quantity of traffic 504 which is the calculation quantity of the traffic before switching with respect to the devices and ports in which the acquired traffic is changed is acquired from the traffic information 114 (S 1002 ). The variation 404 in the traffic after switching in the traffic calculation information is compared with the calculation quantity 504 of the traffic before switching (S 1003 ). Then, it is determined whether a rapid increase of the traffic becomes the traffic or not (S 1004 ).
As a method of determining the bottleneck, there are, for example, the following methods.
In the example of FIG. 10 , a case in which an increase in the traffic after switching becomes larger than that before switching, that is, that traffic is rapidly increased twice is regarded as the bottleneck. As other methods, there are proposed a method of determining that there is the possible of the bottleneck when the traffic is merely increased, a method of registering the maximum value of the traffic due to the specification of the device in advance, and determining whether the increase in the traffic exceeds the maximum value or not, and a method of calculating the maximum value of the traffic of the device by an actual measurement, and determining whether the increase in the traffic exceeds the maximum value or not. In addition, there is proposed a method in which the quantity of traffic is inputted by a user's defined function, and conditions are defined by a calculating formula that determines whether there is the bottleneck or not, and the condition is used for determination.
In the case where it is determined by the above methods that there is the bottleneck, the bottleneck device information is prepared, information on the device identifier, the port identifier and the variation in the traffic which are determined as the bottleneck is prepared, and recorded in the storage device 12 once in order to notify the manager of the information (S 1005 ).
Subsequently, the processing operation of the performance deterioration path calculating process 105 will be described with reference to FIG. 11 .
The performance deterioration path calculating process 105 is executed with the information on the device that is calculated to be the bottleneck detected by the bottleneck determining process 104 of FIG. 3 as an input (S 304 ). The access path that passes through a portion which is determined as the bottleneck is estimated as an access path having the possibility of the performance deterioration, and then extracted.
Since there exist plural devices or ports which are determined as the bottleneck, the respective bottleneck device information 312 is sequentially processed (S 1101 , S 1107 ).
First, the information 115 on the access paths is sequentially retrieved (S 1102 , S 1106 ), and the identifiers of the devices and ports which are judged as the bottleneck are compared with the identifiers of the device and ports which constitute the access paths (S 1103 , S 1104 ). In the case where there exist the identical device and port, since there is the access path that passes through the portion to be determined as the bottleneck, the bottleneck path information 313 is prepared. Then, information on the identifier of the access path which is calculated as having the possibility of the performance deterioration, and a pointer to the bottleneck device information is prepared, and then stored in the storage device 12 once in order to notify the manager of the information (S 1105 ).
Thereafter, the bottleneck path information 313 is transferred to the manager by e-mail with reference to the AP 604 and the operating manager 610 which are registered in correspondence with the access path that passes through the portion to be judged as the bottleneck with reference to the table of the access path information 115 ( FIG. 6 ). Then, the bottleneck path information 313 is displayed on the display device 201 to notify the manager of the bottleneck path information 313 .
As has been described above, according to this embodiment, the information on the switchable access path is collected in advance, and a change in the traffic when the access path is switched over due to the occurrence of the defect of the device such as the respective adaptors or switches is calculated. As a result, the traffic is concentrated at the time of occurrence of the defect, the portion that can be the bottleneck is detected in advance, and the detected information can be notified to the host computer or the manager of AP.
In particular, since the access path is switched over by the multi-path management, information on the logical volume having the possibility that the access from the host computer becomes late, and AP having the possibility that the access to the logical volume in use becomes late is displayed on the display device so as to be notified to the manager.
The manager can readily conduct such work as to weave the access path to the portion that is notified to be concentrated in the access path. As a result, it is possible to improve the important AP operation that leads to the performance deterioration or a reduction in the processing speed which are attributable to the switching of the access path.
The present invention is not limited to the above embodiments, but it is needless to say that the present invention is variously modified within a scope of the subject matter of the present invention. | The present invention grasps in advance a portion in which traffic is concentrated and which may become a bottleneck and simplifies management of an access path. In a storage network system that forms multiple paths between a large-capacity data storage device and a host computer that employs the data storage device, and transfers data by means of a selected path, access paths are managed by a management server. The management server selects a second access path that can be used as a replacement of a first access path that connects the data storage device with the host computer, and calculates the quantity of traffic on the first access path which is associated with a device disposed on the first access path. Also, the management server calculates a variation of the quantity of traffic on the second access path which is associated with a device disposed on the second access path taking the calculated quantity of traffic into consideration. Then, the management server determines whether the device on the second access path causes a bottleneck or not, according to the calculated value of the variation of traffic on the second access path. The management server 11 transfers the determined result to the outside, for example, a display device, and notifies a manager of the determined result. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of application Ser. No. 11/764,571, filed Jun. 18, 2007, which is a continuation of application Ser. No. 11/340,737, filed on Jan. 26, 2006 and now U.S. Pat. No. 7,276,768, which are hereby incorporated by reference herein in its entirety. This divisional application is being filed during the pendency of application Ser. No. 11/764,571, which is a continuation of application Ser. No. 11/340,737, and thereby meets the copendency requirements under 35 U.S.C. § 120 and 35 C.F.R. § 1.78.
FIELD OF THE INVENTION
[0002] The invention relates generally to semiconductor structures and methods and, in particular, to methods for reducing or suppressing latch-up in bulk complementary metal-oxide-semiconductor device structures and semiconductor structures fabricated by these methods.
BACKGROUND OF THE INVENTION
[0003] Complementary metal-oxide-semiconductor (CMOS) technologies integrate P- and N-channel field effect transistors (FETs) to form an integrated circuit on a single semiconductor substrate. Latch-up, which is precipitated by unwanted transistor action of parasitic bipolar transistors inherently present in bulk CMOS devices, may be a significant issue for bulk CMOS technologies. The unwanted parasitic transistor action, which has various triggers, may cause failure of bulk CMOS devices. For space-based applications, latch-up may be induced by the impingement of high energy ionizing radiation and particles (e.g., cosmic rays, neutrons, protons, alpha particles). Because the integrated circuit cannot be easily replaced in space flight systems, the chip failure may prove catastrophic. Hence, designing bulk CMOS devices with a high tolerance to latch-up is an important consideration for circuit operation in the natural space radiation environment, as well as military systems and high reliability commercial applications.
[0004] Bulk CMOS device designs may be adjusted to increase latch-up immunity. For example, latch-up immunity may be increased in 0.25 micron device technologies by building bulk CMOS devices on epitaxial substrates (e.g., a p-type epitaxial layer on a highly-doped p-type substrate wafer). Highly-doped substrate wafers provide excellent current sinks for currents that, if unabated, may initiate latch-up. However, epitaxial substrates are expensive to produce and may increase the design complexity of several critical circuits, such as electrostatic discharge (ESD) protective devices.
[0005] Guard ring diffusions represent another conventional approach for suppressing latch-up. However, guard ring diffusions are costly because they occupy a significant amount of active area silicon real estate. In addition, although guard ring diffusions collect a majority of the minority carriers in the substrate, a significant fraction may escape collection underneath the guard ring diffusion.
[0006] Semiconductor-on-insulator (SOI) substrates are recognized by the semiconductor community as generally free of latch-up. However, CMOS devices are expensive to fabricate on an SOI substrate, as compared to a bulk substrate. Furthermore, SOI substrates suffer from various other radiation-induced failure mechanisms aside from latch-up. Another disadvantage is that SOI devices do not generally come with a suite of ASIC books that would enable simple assembly of low-cost designs.
[0007] Conventional CMOS devices are susceptible to latch-up generally because of the close proximity of N-channel and P-channel devices. For example, a typical CMOS device fabricated on a p-type substrate includes a P-channel transistor fabricated in an N-well and an N-channel transistor fabricated in a P-well. The opposite conductivity N- and P-wells are separated by only a short distance and adjoin across a well junction. This densely-packed bulk CMOS structure inherently forms a parasitic lateral bipolar (PNP) structure and parasitic vertical bipolar (NPN) structure. Latch-up may occur due to regenerative feedback between these PNP and NPN structures.
[0008] With reference to FIG. 1 , a portion of a standard triple-well bulk CMOS structure 30 (i.e., CMOS inverter) includes a P-channel transistor 10 formed in an N-well 12 of a substrate 11 , an N-channel transistor 14 formed in a P-well 16 of the substrate 11 that overlies a buried N-band 18 , and a shallow trench isolation (STI) region 20 separating the N-well 12 from the P-well 16 . Other STI regions 21 are distributed across the substrate 11 . The N-channel transistor 14 includes n-type diffusions representing a source 24 and a drain 25 . The P-channel transistor 10 has p-type diffusions representing a source 27 and a drain 28 . The N-well 12 is electrically coupled by a contact 19 with the standard power supply voltage (Vdd) and the P-well 16 is electrically coupled by a contact 17 to the substrate ground potential. The input of the CMOS structure 30 is connected to a gate 13 of the P-channel transistor 10 and to a gate 15 of the N-channel transistor 14 . The output of CMOS structure 30 is connected to the drain 28 of the P-channel transistor 10 and the drain 25 of the N-channel transistor 14 . The source 27 of the P-channel transistor 10 is connected to Vdd and the source 24 of the N-channel transistor 14 is coupled to ground. Guard ring diffusions 34 , 36 encircle the CMOS structure 30 .
[0009] The n-type diffusions constituting the source 24 and drain 25 of the N-channel transistor 14 , the isolated P-well 16 , and the underlying N-band 18 constitute the emitter, base, and collector, respectively, of a vertical parasitic NPN structure 22 . The p-type diffusions constituting the source 27 and drain 28 of the P-channel transistor 10 , the N-well 12 , and the isolated P-well 16 constitute the emitter, base, and collector, respectively, of a lateral parasitic PNP structure 26 . Because the N-band 18 constituting the collector of the NPN structure 22 and the N-well 12 constituting the base of the PNP structure 26 are shared and the P-well 16 constitutes the base of the NPN structure 22 and also the collector of the PNP structure 26 , the parasitic NPN and PNP structures 22 , 26 are wired to result in a positive feedback configuration.
[0010] A disturbance, such as impinging ionizing radiation, a voltage overshoot on the source 27 of the P-channel transistor 10 , or a voltage undershoot on the source 24 of the N-channel transistor 14 , may result in the onset of regenerative action. This results in negative differential resistance behavior and, eventually, latch-up of the bulk CMOS structure 30 . In latch-up, an extremely low-impedance path is formed between emitters of the vertical parasitic NPN structure 22 and the lateral parasitic PNP structure 26 , as a result of the bipolar bases being flooded with carriers. The low-impedance state may precipitate catastrophic failure of that portion of the integrated circuit. The latched state may only be exited by removal of, or drastic lowering of, the power supply voltage below the holding voltage. Unfortunately, irreversible damage to the integrated circuit may occur almost instantaneously with the onset of the disturbance so that any reaction to exit the latched state is belated.
[0011] What is needed, therefore, is a semiconductor structure and fabrication method for modifying standard bulk CMOS device designs that suppresses latch-up, while being cost effective to integrate into the process flow, and that overcomes the disadvantages of conventional bulk CMOS semiconductor structures and methods of manufacturing such bulk CMOS semiconductor structures.
SUMMARY OF THE INVENTION
[0012] The present invention is generally directed to semiconductor structures and methods that improve latch-up immunity or suppression in standard bulk CMOS device designs, while retaining cost effectiveness for integration into the process flow forming the P-channel and N-channel field effect transistors characteristic of bulk CMOS devices. In accordance with an embodiment of the present invention, a semiconductor structure comprises a substrate of a semiconductor material and first and second doped wells formed in the semiconductor material of the substrate. The second doped well is disposed adjacent to the first doped well. A dielectric-filled trench is defined in the substrate between the first and second doped wells. The trench has a base, first sidewalls intersecting a top surface of the substrate, and second sidewalls disposed between the base and the first sidewalls. The second sidewalls have a wider separation than the first sidewalls.
[0013] In accordance with another embodiment of the present invention, a semiconductor structure comprises a substrate of a semiconductor material and first and second doped wells formed in the semiconductor material of the substrate. The second doped well is disposed adjacent to the first doped well along a well junction. A dielectric-filled trench is defined in the substrate between the first and second doped wells. The trench includes a base, first sidewalls intersecting a top surface of the substrate, and second sidewalls between the base and the first sidewalls. The second sidewalls have a narrower separation than the first sidewalls. The semiconductor material of the substrate bordering the second sidewalls includes a damage region comprising non-monocrystalline semiconductor material. The base of the trench is at a greater depth than the damage region for interrupting the continuity of the non-monocrystalline semiconductor material across the well junction.
[0014] In accordance with another embodiment of the present invention, a semiconductor structure comprises a substrate of a first material characterized by semiconducting properties, first and second doped wells formed in the substrate, a trench defined in the substrate between the first and second doped wells, and a dielectric material filler in the trench. The second doped well is disposed adjacent to the first doped well. The trench includes a base and sidewalls intersecting a top surface of the substrate. A layer of a second material is disposed between the first material at the base of the trench and the dielectric material filler. The first and second materials have a crystal lattice constant difference sufficient to increase carrier recombination velocity.
[0015] In another embodiment of the present invention, a method is provided for fabricating a semiconductor structure in a substrate of semiconductor material. The method comprises forming a trench in the semiconductor material with a first sidewall and a second sidewall each disposed between a base of the trench and a top surface of the substrate. The method further comprises forming an oxygen-enriched region in the semiconductor material of the substrate bounding the first sidewall of the trench near the base and converting the oxygen-enriched region to an oxide region.
[0016] In yet another embodiment of the present invention, a method is provided for fabricating a semiconductor structure in a substrate of semiconductor material. The method comprises forming a trench in the semiconductor material with first sidewalls extending from a base toward a top surface of the substrate and forming a damage region comprising non-monocrystalline semiconductor material at a first depth in the substrate below the base of the first trench. The method further comprises forming a second trench registered with the first trench and having second sidewalls between the base of the first trench to a second depth greater than the first depth. The second trench partitions the damage region such that the non-monocrystalline semiconductor material is discontinuous.
[0017] In yet another embodiment of the present invention, a method is provided for fabricating a semiconductor structure in a substrate of semiconductor material. The method comprises forming a trench in the semiconductor material with sidewalls extending from a base toward a top surface of the substrate and forming an etch mask on the sidewalls. The method further comprises etching the trench to increase a depth of the base from the top surface using an isotropic etchant that removes the semiconductor material of the substrate bordering the trench below the etch mask to widen the sidewalls of the trench below the etch mask.
[0018] In another embodiment of the present invention, a method is provided for fabricating a semiconductor structure in a substrate of a first material characterized by semiconducting properties. The method comprises forming a trench in the first material with sidewalls between a base and a top surface of the substrate and forming a layer of a second material on the base of the trench that has a crystal lattice constant difference in comparison with the first material sufficient to increase carrier recombination velocity in the first material adjacent to the base.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.
[0020] FIG. 1 is a diagrammatic view of a portion of a substrate with a bulk CMOS device constructed in accordance with the prior art.
[0021] FIGS. 2-5 are diagrammatic views of a portion of a substrate at various fabrication stages of a processing method in accordance with an embodiment of the present invention.
[0022] FIG. 5A is a top view of the substrate portion at the fabrication stage of FIG. 5 .
[0023] FIG. 6 is a diagrammatic view of the portion of the substrate at a fabrication stage subsequent to the fabrication stage of FIG. 5 .
[0024] FIGS. 7-12 are diagrammatic views of a portion of a substrate at various fabrication stages of a processing method in accordance with an alternative embodiment of the present invention.
[0025] FIGS. 13-15 are diagrammatic views of a portion of a substrate at various fabrication stages of a processing method in accordance with an alternative embodiment of the present invention.
[0026] FIG. 16 is a diagrammatic view similar to FIG. 14 depicting a portion of a substrate at a fabrication stage of a processing method in accordance with an alternative embodiment of the present invention.
[0027] FIG. 17 is a diagrammatic view similar to FIG. 13 depicting a portion of a substrate at a fabrication stage of a processing method in accordance with an alternative embodiment of the present invention.
[0028] FIG. 18 is a diagrammatic view similar to FIG. 3 depicting a portion of a substrate at a fabrication stage of a processing method in accordance with an alternative embodiment of the present invention.
DETAILED DESCRIPTION
[0029] The present invention provides an isolation region that limits the effect of the vertical parasitic NPN structure and the lateral parasitic PNP structure responsible for latch-up in triple-well bulk CMOS devices. The invention is advantageously implemented in the context of bulk CMOS devices where pairs of N-channel and P-channel field effect transistors are formed adjacent to each other in a P-well within an N-band and an N-well, respectively, and the P-well is isolated from the N-well by a shallow trench isolation (STI) region. Specifically, the latchup immunity of a standard bulk CMOS triple well structure is improved by modifying the geometry of the STI region or by selectively adding damage regions to the STI region in a manner that significantly reduces the susceptibility to latch-up. The present invention will now be described in greater detail by referring to the drawings that accompany the present application.
[0030] With reference to FIG. 2 , a bulk substrate 40 of a monocrystalline semiconductor material is obtained. Substrate 40 may include a low-defect epitaxial layer for device fabrication that is grown by an epitaxial growth process, such as chemical vapor deposition (CVD) using a silicon source gas (e.g., silane). Substrate 40 may be a single crystal silicon wafer containing a relatively light concentration of a dopant providing p-type conductivity. For example, substrate 40 may be lightly doped with 5×10 15 cm −3 to 1×10 17 cm −3 of a p-type dopant, such as boron, by in situ doping during deposition of the epitaxial layer.
[0031] A pad structure 42 is formed on a top surface 41 of the substrate 40 . The pad structure 42 includes a first pad layer 44 and a thinner second pad layer 46 separating the first pad layer 44 from the substrate 40 . The constituent material(s) of pad layers 44 , 46 advantageously etch selectively to the semiconductor material constituting substrate 40 . The first pad layer 44 may be a conformal layer of nitride (Si 3 N 4 ) formed by a thermal CVD process like low pressure chemical vapor deposition (LPCVD) or a plasma-assisted CVD process. The second pad layer 46 may be silicon oxide (SiO 2 ) grown by exposing substrate 40 to either a dry oxygen ambient or steam in a heated environment or deposited by a thermal CVD process. The second pad layer 46 may operate as a buffer layer to prevent any stresses in the material constituting the first pad layer 44 from causing dislocations in the semiconductor material of substrate 40 .
[0032] Shallow trenches 48 are formed in the semiconductor material of substrate 40 by a conventional lithography and subtractive etching process that utilizes a shallow trench pattern imparted in the pad structure 42 ( FIG. 2 ) or, optionally, in a patterned hard mask (not shown) formed on pad structure 42 . The shallow trench pattern may be created in pad structure 42 by applying a photoresist (not shown) on pad layer 44 , exposing the photoresist to a pattern of radiation to create a latent shallow trench pattern in the photoresist, and developing the latent shallow trench pattern in the exposed photoresist. An anisotropic dry etching process, such as reactive-ion etching (RIE) or plasma etching, may then be used to transfer the trench pattern from the patterned resist into the pad layers 44 , 46 . The etching process, which may be conducted in a single etching step or multiple etching steps with different etch chemistries, removes portions of the pad structure 42 visible through the trench pattern in the patterned resist and stops vertically on the substrate 40 . After etching is concluded, residual resist is stripped from the pad structure 42 by, for example, plasma ashing or a chemical stripper.
[0033] The shallow trench pattern is then transferred from the patterned pad layer 44 into the underlying substrate 40 with an anisotropic dry etching process. The anisotropic dry etching process may be constituted by, for example, RIE, ion beam etching, or plasma etching using an etch chemistry (e.g., a standard silicon RIE process) that removes the constituent semiconductor material of substrate 40 selective to the materials constituting the pad layers 44 , 46 . Each of the shallow trenches 48 defined in the semiconductor material of substrate 40 includes opposite sidewalls 50 , 52 , which are substantially mutually parallel and oriented substantially perpendicular to the top surface 41 of substrate 40 , that extend into the substrate 40 to a bottom surface or base 54 .
[0034] Energetic ions, as indicated diagrammatically by singled-headed arrows 56 , are introduced by an ion implantation process into the substrate 40 to create an oxygen-enriched or oxygen implanted region 58 proximate to and just beneath the base 54 of each shallow trench 48 . The energetic ions 56 , which are generated from a source gas, are directed to impinge the top surface 41 of the substrate 40 at normal or near-normal incidence, although the invention is not so limited. The ions 56 may be implanted with the substrate 40 at or near room or ambient temperature, although the present invention is not so limited.
[0035] The ions 56 lose energy via scattering events with atoms and electrons in the semiconductor material constituting substrate 40 as the ions 56 penetrate the substrate 40 . The ions 56 eventually dissipate all of their initial kinetic energy and stop in the substrate 40 to produce the oxygen implanted regions 58 . The stopped ions 56 in the oxygen implanted regions 58 are characterized by a depth profile distributed about a projected range, which is measured as a perpendicular distance of the damage peak from the top surface 41 . The depth profile is characterized by a range straggle, which represents a deviation or second moment of the stopped ions 56 about the projected range. Essentially all of the implanted ions 56 come to rest in the semiconductor material of substrate 40 within a distance of three times the range straggle from the projected range. The implanted ions 56 also have a lateral straggle that causes side edges 60 , 62 of the oxygen implanted regions 58 to extend beyond the sidewalls 50 , 52 of each shallow trench 48 .
[0036] The ions 56 may originate from a source selected to provide, when ionized and accelerated to impart kinetic energy, oxygen ions. The implanted species may be either charged atomic oxygen ions (O + ) or molecular ions (O +2 ). Advantageously, the peak atomic concentration for the implanted ions 56 in the oxygen implanted regions 58 may be in the range of 5×10 19 cm −3 to 5×10 21 cm −3 and, in certain embodiments, may be as low as 5×10 18 cm −3 to provide the requisite oxygen concentration. For example, a suitable dose of implanted O + may range from 1×10 14 cm −2 to 5×10 16 cm −2 at a kinetic energy between about 10 keV and about 50 keV, although the invention is not so limited. The present invention contemplates other implant conditions, i.e., energy and dose, may be used that are capable of forming oxygen implanted regions 58 in substrate 40 . The ions 56 are implanted across the top surface 41 of the entire substrate 40 , although certain regions of substrate 40 may be optionally protected by a block mask during implantation. Ions of an oxidation rate enhancing atomic species, such as germanium (Ge), silicon (Si), or arsenic (As) for n-well applications, or boron difluoride (BF 2 ) for p-well applications, may be co-implanted with ions 56 . A block mask (not shown) of, for example, photoresist may protect a portion of the substrate 40 during the ion implantation process.
[0037] With reference to FIG. 3 in which like reference numerals refer to like features in FIG. 2 and at a subsequent fabrication stage, spacers 64 , 66 are formed on the sidewalls 50 , 52 of each shallow trench 48 . Spacers 64 , 66 may be defined from a conformal layer (not shown) of a dielectric material, such as 5 nm to 15 nm of nitride deposited by a CVD process, that is anisotropically etched using a reactive ion etch (RIE) or plasma etching process. The etching process removes the material of the conformal layer (not shown) primarily from horizontal surfaces selective to (i.e., with a significantly greater etch rate than) the constituent semiconductor material of substrate 40 . The base 54 of each shallow trench 48 is exposed after the spacers 64 , 66 are formed.
[0038] With reference to FIG. 4 in which like reference numerals refer to like features in FIG. 3 and at a subsequent fabrication stage, a majority of each of the oxygen implanted regions 58 ( FIG. 3 ) is converted by a thermal oxidation process to one of a plurality of oxide regions 68 each consisting of an oxide (e.g., silicon dioxide). The thermal oxidation process may be performed in a dry or wet oxidizing ambient atmosphere and at a temperature ranging from about 750° C. to about 1100° C. The oxidizing species from the oxidizing ambient atmosphere penetrates the substrate 40 through the exposed base 54 of each shallow trench 48 in order to reach the oxygen implanted regions 58 . Spacers 64 , 66 protect the sidewalls 50 , 52 of each shallow trench 48 against unwanted oxidation. The implanted oxygen in the oxygen implanted regions 58 ( FIG. 3 ) enhances the oxidation rate for the corresponding semiconductor material of substrate 40 when exposed to the oxidizing species from the oxidizing ambient atmosphere.
[0039] The perimeter of each oxide region 68 defines a curved boundary 69 that extends laterally or horizontally of the sidewalls 50 , 52 of each shallow trench 48 because of the lateral oxide growth during the thermal oxidation process. The lateral extent of the concave boundary 69 of each oxide region 68 roughly coincides with the side edges 60 , 62 of the oxygen implanted regions 58 or may be slightly narrower than the side edges 60 , 62 . Each oxide region 68 defines a degree of undercut relative to the sidewalls 50 , 52 and the degree of undercut increases with increasing energy of the implanted ions 56 . The lateral oxide growth defines lateral extensions 73 , 75 of STI regions 74 ( FIG. 5 ), effectively defining sidewalls 70 , 72 that widen each shallow trench 48 relative to sidewalls 50 , 52 , and increases the depth of base 54 relative to the top surface 41 . The base 54 of each shallow trench 48 is effectively deepened to a greater depth by the oxidation process forming oxide regions 68 as the remaining open volume in each shallow trench 48 is filled with dielectric material in a subsequent fabrication stage.
[0040] A portion of each oxygen implanted region 58 ( FIG. 3 ) may remain, after the thermal oxidation process, as a damage region 71 proximate to the curved boundary 69 of the corresponding oxide region 68 . The stopping of the ions 56 ( FIG. 2 ) implanted in substrate 40 damages the constituent semiconductor material to form non-monocrystalline semiconductor material confined within damage region 71 . Energy transferred by nuclear collisions between ions 56 and target atoms in the substrate 40 displaces those target atoms from their original lattice sites and, as a consequence, permanently damages the semiconductor material of the substrate 40 . When each individual ion 56 displaces a target atom of the substrate 40 in a nuclear collision, a recoil cascade is initiated that dissipates the transferred kinetic energy by collisions with other target atoms. The recoil cascade generates additional vacancies and interstitial atoms in the lattice structure of substrate 40 dispersed among the atoms in the crystalline lattice structure remaining on regular lattice sites. The damage in the damage region 71 may comprise extended crystal lattice defects that are larger than point defects and disrupt long range order, or may render the crystalline structure amorphous. The crystalline damage in the damage region 71 coincides approximately with the depth profile of the stopped ions 56 and is stable in that the damage region 71 remains after subsequent fabrication steps.
[0041] With reference to FIGS. 5 and 5 A in which like reference numerals refer to like features in FIG. 4 and at a subsequent fabrication stage, the shallow trenches 48 are filled with amounts of an insulating or dielectric material, such as a high-density plasma (HDP) oxide or tetraethylorthosilicate (TEOS), deposited across the pad layer 44 and planarized by, for example, a CMP process. An optional high temperature process step may be used to densify the TEOS fill. The pad structure 42 is removed by a planarization process to define shallow trench isolation (STI) regions 74 in the substrate 40 having a top surface substantially co-planar or flush with the top surface 41 of substrate 40 .
[0042] With reference to FIG. 6 in which like reference numerals refer to like features in FIG. 5 and at a subsequent fabrication stage, standard bulk CMOS processing follows, which includes formation of a triple-well structure consisting of an N-well 76 , a P-well 78 , and a deep buried N-well or N-band 80 in the substrate 40 . The buried N-band 80 supplies electrical isolation for the P-well 78 . This triple-well construction permits the optimization of bias potentials for both N- and P-wells 76 , 78 . The P-well 78 is arranged between the N-band 80 and the top surface 41 .
[0043] The N-well 76 , as well as other N-wells (not shown) dispersed across the substrate 40 , are likewise formed by patterning a mask layer (not shown) applied on the top surface 41 with techniques known in the art, and implanting an appropriate n-conductivity type impurity into the substrate 40 in unmasked regions. The N-band 80 , as well as other N-bands (not shown) dispersed across the substrate 40 , are formed by patterning another mask layer (not shown), such as a photoresist, applied on top surface 41 and implanting an appropriate n-conductivity type impurity into the substrate 40 in this set of unmasked regions. The P-well 78 , as well as other P-wells (not shown) dispersed across the substrate 40 , are likewise formed by patterning another mask layer (not shown) applied on top surface 41 and implanting an appropriate p-conductivity type impurity into the substrate 40 in this set of unmasked regions. Typically, the P-well 78 is formed by counterdoping the N-band 80 and has an opposite conductivity type from the N-well 76 and N-band 80 . Generally, the dopant concentration in the N-well 76 ranges from about 5.0×10 17 cm −3 to about 7.0×10 18 cm −3 , the dopant concentration in the P-well 78 ranges from about 5.0×10 17 cm −3 to about 7.0×10 18 cm −3 , and the dopant concentration in the N-band 80 ranges from about 5.0×10 17 cm −3 to about 70×10 18 cm −3 . A thermal anneal may be required to electrically activate the implanted impurities operating as the p-type and n-type dopants.
[0044] An N-channel transistor 82 is built using the P-well 78 , and a P-channel transistor 84 is built using the N-well 78 to define a bulk CMOS device. The N-channel transistor 82 includes n-type diffusions in the semiconductor material of substrate 40 representing a source region 86 and a drain region 88 that flank opposite sides of a channel region in the semiconductor material of substrate 40 , a gate electrode 90 overlying the channel region, and a gate dielectric 92 electrically isolating the gate electrode 90 from the substrate 40 . The P-channel transistor 84 includes p-type diffusions in the semiconductor material of substrate 40 representing a source region 94 and a drain region 96 that flank opposite sides of a channel region in the semiconductor material of substrate 40 , a gate electrode 98 overlying the channel region, and a gate dielectric 100 electrically isolating the gate electrode 98 from the substrate 40 . Other structures, such as sidewall spacers (not shown), may be included in the construction of the N-channel transistor 82 and the P-channel transistor 84 .
[0045] The conductor used to form the gate electrodes 90 , 98 may be, for example, polysilicon, silicide, metal, or any other appropriate material deposited by a CVD process, etc. The source and drain regions 86 , 88 and the source and drain regions 94 , 96 may be formed in the semiconductor material of substrate 40 by ion implantation of suitable dopant species having an appropriate conductivity type. The gate dielectrics 92 , 100 may comprise any suitable dielectric or insulating material like silicon dioxide, silicon oxynitride, a high-k dielectric, or combinations of these dielectrics. The dielectric material constituting dielectrics 92 , 100 may be between about 1 nm and about 10 nm thick, and may be formed by thermal reaction of the semiconductor material of the substrate 40 with a reactant, a CVD process, a physical vapor deposition (PVD) technique, or a combination thereof.
[0046] Processing continues to complete the semiconductor structure, including forming electrical contacts to the gate electrodes 90 , 98 , source region 86 , drain region 88 , source region 94 , and drain region 96 . The contacts may be formed using any suitable technique, such as a damascene process in which an insulator is deposited and patterned to open vias, and then the vias are filled with a suitable conductive material, as understood by a person having ordinary skill in the art. The N-channel and P-channel transistors 82 , 84 are coupled using the contacts with other devices on substrate 40 and peripheral devices with a multilevel interconnect structure consisting of conductive wiring and interlevel dielectrics (not shown). A contact 102 is also formed in substrate 40 that is electrically coupled with the N-well 76 for supplying the standard power supply voltage (Vdd) to the N-well 76 . Another contact 104 is formed in substrate 40 for coupling the P-well 78 with the substrate ground potential.
[0047] In accordance with the principles of the invention, the lateral extensions 73 , 75 of the bottom portion of the STI regions 74 increase the base width or P-well path for the parasitic NPN structure 22 ( FIG. 1 ) and the base width or N-well path for the PNP structure 26 ( FIG. 1 ). As a consequence, holes traversing the N-well 76 to the P-well 78 , which constitutes the collector of the PNP structure 26 , and electrons traversing the P-well 78 to the N-well 76 , which constitutes the collector of the NPN structure 22 , must flow around the lateral extensions 73 , 75 , which defines an inverted-T structure. A bump in the electric potential forms at the lateral extensions 73 , 75 , due to the concavity of the silicon surface about curved boundary 69 and bounding the side edges 70 , 72 of the lateral extensions 73 , 75 . This potential bump impedes the flow of minority carriers and results in reduced beta for both parasitic NPN and PNP structures 22 , 26 . The damage regions 71 in the semiconductor material of the substrate 40 , if present, are believed to reduce the minority carrier lifetimes and to contribute to the reduction of the bipolar gain of the parasitic NPN and PNP structures 22 , 26 .
[0048] With reference to FIG. 7 in which like reference numerals refer to like features in FIG. 2 and in accordance with an alternative embodiment of the present invention that does not rely on an ion implantation process, the anisotropic dry etching process transferring the trenches 48 from the patterned pad layer 44 into the underlying substrate 40 is halted at an intermediate base 106 that is shallower than base 54 ( FIG. 2 ). A conformal layer 108 of a dielectric material, such as 5 nm to 15 nm of silicon nitride deposited by a CVD process, is formed on the pad layer 44 and the sidewalls 50 , 52 and intermediate base 106 of trenches 48 .
[0049] With reference to FIG. 8 in which like reference numerals refer to like features in FIG. 7 and at a subsequent fabrication stage, the conformal layer 108 is anisotropically etched using, for example, an RIE or plasma etching process that removes the material constituting the conformal layer primarily from horizontal surfaces selective to (i.e., with a significantly greater etch rate than) the constituent semiconductor material of substrate 40 . Un-removed portions of the conformal layer 108 define spacers 110 , 112 on the sidewalls 50 , 52 of each shallow trench 48 .
[0050] Using the pad structure 42 and spacers 110 , 112 as a mask, an anisotropic etching process is used to deepen the shallow trenches 48 , which defines base 54 . Respective surfaces 50 a , 52 a of the semiconductor material of substrate 40 are exposed between base 54 and the spacers 110 , 112 , as is the surface along base 54 . The depth difference between base 54 and intermediate base 106 , which is determined based upon depths measured as a perpendicular distance relative to surface 41 , may be, for example, about 0.1 μm. The depth difference also defines the vertical height of the surfaces 50 a , 52 a across which the semiconductor material of substrate 40 borders the shallow trench 48 and, hence, is unmasked by spacers 110 , 112 . The absolute depths to which the shallow trenches 48 are etched may vary according to device design.
[0051] With reference to FIG. 9 in which like reference numerals refer to like features in FIG. 8 and at a subsequent fabrication stage, an isotropic etching process is used to etch the semiconductor material of substrate 40 bordering shallow trenches 48 exposed across the surfaces 50 a , 52 a and base 54 . The isotropic etching process, which may be conducted in a single etching step or multiple steps with different etch chemistries, selectively removes the semiconductor material of substrate 40 vertically to slightly deepen base 54 . The isotropic etching process also removes the semiconductor material of substrate 40 laterally across the surfaces 50 a , 52 a to define sidewalls 114 , 116 that have a wider separation than sidewalls 50 , 52 . During the isotropic etching process, the spacers 110 , 112 mask and protect sidewalls 50 , 52 above surfaces 50 a , 52 a against removal. For example, the etching process may rely on an isotropic silicon etchant such as a wet or dry hydrofluoric acid etchant.
[0052] With reference to FIG. 10 in which like reference numerals refer to like features in FIG. 9 and at a subsequent fabrication stage, spacers 110 , 112 are stripped from the sidewalls 50 , 52 of each shallow trench 48 using an appropriate etching process. A liner 118 is formed on the sidewalls 50 , 52 , sidewalls 114 , 116 , and base 54 , as well as on the pad layer 44 . The liner 118 may be, for example, silicon oxide grown by exposing the unmasked semiconductor material of substrate 40 to either a dry oxygen ambient or steam in a heated environment. Another optional liner (not shown) of, for example, silicon nitride may be applied as a diffusion barrier to prevent impurity migration from the trench fill material into the semiconductor material of substrate 40 bordering the shallow trenches 48 . The liner 118 also operates to repair any etch damage incurred by the sidewalls 50 , 52 , sidewalls 114 , 116 , and base 54 of each shallow trench 48 .
[0053] With reference to FIG. 11 in which like reference numerals refer to like features in FIG. 10 and at a subsequent fabrication stage, the shallow trenches 48 are filled with an insulating or dielectric material, such as HDP oxide or TEOS, deposited across the pad layer 44 and planarized by, for example, a CMP process. The pad structure 42 and excess liner 118 on the pad layer 44 are removed and planarized to define the STI regions 74 in the substrate 40 by a planarization process that makes the top surface of the STI regions 74 substantially co-planar or flush with the top surface 41 of substrate 40 . Portions of the dielectric material fill the concavities bounded by sidewalls 114 , 116 to form the lateral extensions 73 , 75 at the bottom of the STI regions 74 .
[0054] With reference to FIG. 12 in which like reference numerals refer to like features in FIG. 11 and at a subsequent fabrication stage, standard bulk CMOS processing follows as described above with regard to FIG. 6 to form the N- and P-wells 76 , 78 , the N-band 80 , the N-channel transistor 82 , the P-channel transistor 84 , and contacts 102 , 104 in the substrate 40 . A person having ordinary skill in the art will appreciate that this embodiment of the present invention may be advantageously implemented in a dual-well CMOS structure that lacks the N-band 80 .
[0055] With reference to FIG. 13 in which like reference numerals refer to like features in FIG. 2 and in accordance with an alternative embodiment of the present invention that minimizes damage across a well junction 142 ( FIG. 15 ) between the subsequently-formed N- and P-wells 138 , 140 ( FIG. 15 ) in a dual-well structure, a crystal damaging species is ion implanted into the base 54 of the shallow trenches 48 before the STI regions 74 ( FIG. 15 ) are defined by filling the shallow trenches 48 with dielectric material. Before implantation, the shallow trenches 48 are lined with a liner 121 consisting of one or more individual layers (not shown) of suitable materials, such as 1 nm to 3 nm of thermally grown silicon oxide covered by 4 nm to 20 nm of silicon nitride deposited conformally by a CVD process.
[0056] Local crystalline damage regions 124 , which include semiconductor material of substrate 40 that has been converted to a non-monocrystalline state and includes point and extended defects, are formed by introducing energetic ions, as indicated diagrammatically by singled-headed arrows 122 , by an ion implantation process into the substrate 40 . The energetic ions 122 , which are generated from a source gas, are directed to impinge the substrate 40 at normal or near-normal incidence. The ions 122 may originate from a source gas selected to provide, when ionized and accelerated to impart kinetic energy, neutral impurities in silicon like nitrogen (N), oxygen (O), carbon (C), gold (Au), platinum (Pt), germanium (Ge), and silicon (Si), and other suitable elements capable of inducing lattice damage. The ions 122 may be implanted with the substrate 40 at or near room or ambient temperature, although the present invention is not so limited. The pad structure 42 masks underlying regions of the substrate 40 against receiving an ion dose during the ion implantation process such that only damage regions 124 of the substrate 40 are implanted with a significant dose of ions 122 .
[0057] The trajectories of the ions 122 penetrate the substrate 40 across base 54 of at least the shallow trench 48 that, after subsequent fabrication stages, intersects the well interface 142 ( FIG. 15 ), as well as optionally other trenches 48 . The ions 122 lose energy via scattering events with atoms and electrons in the semiconductor material constituting substrate 40 . Kinetic energy lost in nuclear collisions displaces target atoms of the substrate 40 from their original lattice sites and permanently damages the substrate 40 . When each individual ion 122 collides with a target atom of the substrate 40 , a recoil cascade is initiated that dissipates the transferred kinetic energy by collisions with other target atoms. The recoil cascade generates vacancies and interstitial atoms in the lattice structure of substrate 40 among the atoms in the lattice structure remaining on regular lattice sites.
[0058] The ions 122 eventually lose all of their initial kinetic energy and stop in the substrate 40 to produce one of the damage regions 124 of non-monocrystalline semiconductor material near the base 54 of each shallow trench 48 . The crystalline damage in the damage regions 124 coincides approximately with the depth profile of the stopped ions 122 . Similar to the stopped ions 122 , each damage region 124 is characterized by a depth profile distributed about a projected range, which is measured as a perpendicular distance of the damage peak from the top surface 41 , and having a range straggle. Essentially all of the implanted ions 122 come to rest within a distance of three times the range straggle from the projected range, which implies that the damage has a similar distribution. After the ion implantation is concluded, uncombined vacancies and interstitial atoms remain and are distributed across the thickness of the damage regions 124 , as well as extended defects. The depth profile of the implanted ions 122 and damage also has a characteristic lateral straggle such that ions 122 and damage extend laterally of the sidewalls 50 , 52 , as indicated generally by boundary 126 .
[0059] The ion dose is preferably selected such that the peak atomic concentration of the implanted ions 122 in each damage region 124 exceeds the solid solubility of the impurity in the constituent material of the substrate 40 . By exceeding the solid solubility, subsequent heated process steps do not anneal the crystalline defects in the damage regions 124 . Advantageously, the peak atomic concentration for the implanted ions 122 in each damage region 124 may be in the range of 5×10 19 cm −3 to 5×10 21 cm −3 and, in certain embodiments, may be as low as 5×10 18 cm −3 to provide the requisite crystalline damage. For example, a suitable implanted ion dose may range from 1×10 14 cm −2 to 5×10 16 cm −2 at a kinetic energy between about 10 keV and about 50 keV, although the invention is not so limited. The present invention contemplates other implant conditions, i.e., energy and dose, that are capable of forming the damage regions 124 in substrate 40 . The ions 122 are implanted across the top surface 41 of the entire substrate 40 , although certain regions of substrate 40 may be optionally protected by a block mask (not shown) during implantation.
[0060] With reference to FIG. 14 in which like reference numerals refer to like features in FIG. 13 and at a subsequent fabrication stage, a pattern of deep trenches 128 is formed in the substrate 40 by a conventional lithography and subtractive etching process. To that end, a photoresist 130 is applied on pad layer 44 and exposed to a pattern of radiation that, after developing, creates a deep trench pattern. An anisotropic dry etching process, such as reactive-ion etching (RIE) or plasma etching, may then be used to transfer each deep trench 128 from the deep trench pattern in the patterned photoresist 130 into the substrate 40 . The deep trench pattern in the photoresist 130 is tailored such that each deep trench 128 is registered with a corresponding one of the shallow trenches 48 overlying the future location of the well junction 142 ( FIG. 15 ).
[0061] The damage region 124 ( FIG. 13 ) coinciding with the shallow trench 48 associated with deep trench 128 is partially removed by the anisotropic dry etching process forming the deep trench 128 . As a result, sidewalls 127 , 129 of the deep trench 128 are each flanked by a corresponding one of a pair of damage regions 132 , 134 . The deep trench 128 separates damage regions 132 , 134 so that the crystalline damage in the semiconductor material of substrate 40 (i.e., the non-monocrystalline semiconductor material) is discontinuous and interrupted across the well junction 142 ( FIG. 15 ). Specifically, a bottom or base 131 of the deep trench 128 is at a greater depth than the damage regions 132 , 134 . The sidewalls 127 , 129 are narrower than the sidewalls 50 , 52 of the corresponding shallow trench 48 and the base 131 is at a greater depth, measured perpendicular to surface 41 , than base 54 of the corresponding shallow trench 48 .
[0062] With reference to FIG. 15 in which like reference numerals refer to like features in FIG. 14 and at a subsequent fabrication stage, residual photoresist 130 ( FIG. 14 ) is stripped by, for example, plasma ashing or a chemical stripper after the deep trenches 128 are etched. The shallow trenches 48 are filled with amounts of an insulating or dielectric material, such as HDP oxide or TEOS, deposited across the pad layer 44 and planarized by, for example, a CMP process. The pad structure 42 is removed and planarized to define the STI regions 74 in the substrate 40 by a planarization process that makes the top surface of the STI regions 74 substantially co-planar or flush with the top surface 41 of substrate 40 . Portions of the dielectric material also fill the deep trench 128 to define a pigtail or extension 136 that separates the damage regions 132 , 134 . Standard bulk CMOS processing follows as described above with regard to FIG. 6 to form N- and P-wells 138 , 140 , similar to N- and P-wells 76 , 78 ( FIG. 6 ), the N-channel transistor 82 , the P-channel transistor 84 , and contacts 102 , 104 in the substrate 40 . A person having ordinary skill in the art will appreciate that this embodiment of the present invention may be advantageously implemented in a triple-well CMOS structure that includes an N-band (not shown) similar to N-band 80 ( FIG. 6 ).
[0063] The selectively introduced lattice damage reduces the current gains of the parasitic NPN and PNP structures 22 , 26 ( FIG. 1 ) without degrading well leakage of the N- and P-wells 138 , 140 . Ordinarily, crystal damage across well junction 142 between the N- and P-wells 138 , 140 causes a depletion region in a dual-well bulk CMOS technology, which increases the well leakage currents. In accordance with the present invention, the relatively narrow deep trench 128 is aligned relative to the corresponding shallow trench 48 to intersect the well junction 142 between the N-well 138 and P-well 140 , thus removing the damaged semiconductor material across the well junction 142 . Thus, the damage in damage regions 132 , 134 exists only within the portion of the N- and P-wells 138 , 140 that constitutes the base of the parasitic NPN and PNP structures 22 , 26 ( FIG. 1 ). The crystal damage in the base regions shortens the minority carrier lifetime of the carriers emitted by the emitters and, thereby, reduces the bipolar gain to the point where latch-up is not sustained. Because the damage is located away from the well junction 142 , well leakage is not degraded.
[0064] With reference to FIG. 16 in which like reference numerals refer to like features in FIG. 14 and in accordance with an alternative embodiment of the present invention, ions 152 , similar or identical to ions 122 ( FIG. 13 ), may be directed into the sidewalls 127 , 129 of the deep trench 128 . An implantation mask 154 of, for example, HDP oxide is applied to self align the impinging ions 152 to the sidewalls 127 , 129 and to prevent impinging ions 152 from entering the semiconductor material of the substrate 40 near the base 131 of the deep trench 128 . A portion of the implantation mask 154 masks the base 131 of the deep trench 128 , which prevents damage to the well junction 142 . The implanted ions 152 form damage regions 156 , 158 in the semiconductor material of substrate 40 that are similar or identical to damage regions 132 , 134 ( FIG. 14 ). These damage regions 156 , 158 of non-monocrystalline semiconductor material may be used in conjunction with damage regions 132 , 134 for suppressing latch-up. Processing continues as shown in FIG. 15 to complete semiconductor structure.
[0065] With reference to FIG. 17 in which like reference numerals refer to like features in FIG. 13 and in accordance with an alternative embodiment of the present invention, a high defect region may be produced near the base 54 of the shallow trenches 48 without ion implantation. To that end, protective spacers 144 , 146 of an insulating material, such as silicon oxide or silicon nitride, are formed on the sidewalls 50 , 52 of at least the shallow trench 48 that, after subsequent fabrication stages, intersects the well junction 142 .
[0066] A layer 148 of a semiconductor material, such as SiGe, having a lattice mismatch with the semiconductor material of the substrate 40 is then deposited or grown at the bottom of the shallow trench 48 . The protective spacers 144 , 146 guard the sidewalls 50 , 52 against the formation of an extraneous layer (not shown) of the material constituting layer 148 on sidewalls 50 , 52 . The lattice mismatch or crystal lattice constant difference between the materials in layer 148 and substrate 40 results in a region 150 of high carrier recombination velocity in the substrate 40 beneath the shallow trench 48 . Region 150 is characterized by a high recombination velocity and getters or attracts carriers in transit to the collectors of the parasitic NPN and PNP structures 22 , 26 ( FIG. 1 ). Processing continues as shown in FIG. 14 to complete the semiconductor structure ( FIG. 15 ).
[0067] With reference to FIG. 18 in which like reference numerals refer to like features in FIG. 3 and in accordance with an alternative embodiment of the present invention, the oxygen implanted regions 58 ( FIG. 3 ) may be removed with an appropriate isotropic etching process to leave open cavities or voids 59 . The open voids 59 , which communicate with a corresponding one of the shallow trenches 48 , are each filled with dielectric material when the shallow trenches 48 are filled. The dielectric-filled open voids 59 define the lateral extensions 73 , 75 ( FIG. 4 ). Processing continues as shown in FIG. 4 to complete the semiconductor structure.
[0068] References herein to terms such as “vertical”, “horizontal”, etc. are made by way of example, and not by way of limitation, to establish a frame of reference. The term “horizontal” as used herein is defined as a plane parallel to the top surface 41 of substrate 40 , regardless of its actual spatial orientation. The term “vertical” refers to a direction perpendicular to the horizontal, as just defined. Terms, such as “on”, “above”, “below”, “side” (as in “sidewall”), “higher”, “lower”, “over”, “beneath” and “under”, are defined with respect to the horizontal plane. It is understood that various other frames of reference may be employed for describing the present invention without departing from the spirit and scope of the present invention.
[0069] The fabrication of the semiconductor structure herein has been described by a specific order of fabrication stages and steps. However, it is understood that the order may differ from that described. For example, the order of two or more fabrication steps may be switched relative to the order shown. Moreover, two or more fabrication steps may be conducted either concurrently or with partial concurrence. In addition, various fabrication steps may be omitted and other fabrication steps may be added. It is understood that all such variations are within the scope of the present invention. It is also understood that features of the present invention are not necessarily shown to scale in the drawings.
[0070] While the present invention has been illustrated by a description of various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Thus, the invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative example shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicants' general inventive concept. | Semiconductor structures and methods for suppressing latch-up in bulk CMOS devices. The semiconductor structure comprises a shaped-modified isolation region that is formed in a trench generally between two doped wells of the substrate in which the bulk CMOS devices are fabricated. The shaped-modified isolation region may comprise a widened dielectric-filled portion of the trench, which may optionally include a nearby damage region, or a narrowed dielectric-filled portion of the trench that partitions a damage region between the two doped wells. Latch-up may also be suppressed by providing a lattice-mismatched layer between the trench base and the dielectric filler in the trench. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a method of forming and processing an advancing endless synthetic filament yarn, and specifically to a method of withdrawing the yarn from a spinneret or a drawing zone by means of a feed system, and then winding the yarn onto a rotating tube to form a yarn package. A method of this type is described, for example, in the trade journal "Chemiefasern/Textilindustrie", September 1991, pp. 1002, 1004. See also DE-A 22 04 397.
The known method is a single-step spinning method for the production of a multifilament yarn, in which the yarn is withdrawn from the spinneret at a high speed by the feed system, and subsequently wound by means of a takeup system. The feed system comprises two godets which are each looped by the yarn at 180°. This means that the yarn tension above the godets starts with a lower withdrawal tension and increases continuously toward the draw rolls by reason of air friction and other frictional influences until reaching the tension under which the yarn contacts the draw rolls. In this process, the yarn tension is increased such that the freshly spun yarn undergoes a complete or partial drawing. It is, however, undesirable and unsuitable to wind the yarn on the package at the same high tension as well. According to the described method, the two godets have a polished surface which has been hard chrome plated. This generates high frictional resistance between the yarn and the draw roll surface, in respect of both sliding friction and static friction. To achieve the necessary decrease in yarn tension, it is necessary that the spin-takeup apparatus have two godets or godets with a yarn displacement roll so as to achieve an adequate reduction of yarn tension and a good uniformity (Uster value). At delivery speeds in excess of 5000 m/min., in the production of yarns consisting of very thin filaments the known method suffers from the disadvantage that filaments often break, and that the broken filaments can no longer be advanced by the godet, but are entrained by air currents which surround the godet, and are subsequently formed into a lap on the godet. Such a lap results in an interruption of the operation. Likewise, the threading of the yarn is rendered difficult, since the yarn breaks due to the great difference in speed. It is also very difficult to adjust the speeds of the feed system on the one hand and of the takeup system and yarn traverse motion on the other. It is necessary that these speeds are adjustable independently of one another. However, their adjustment relative to each other must be very accurate to prevent tearing or slackening (too low yarn tension). Here, too, there exists a potential for damaging the yarn or interrupting the operation by breaking or forming laps. In particular, it is necessary that the circumferential speed of the yarn takeup package be somewhat lower than the circumferential speed of the feed system. On the other hand, it should not be substantially lower than the geometric sum of circumferential speed of the yarn package and the traverse speed, at which the yarn reciprocates along the package. Finally, in this process it is difficult to set the desired yarn tension at a constant level.
The disadvantages of the above process are avoided by in the so-called godet-free spinning. In this process, the yarn is directly withdrawn from the spinneret directly by the yarn takeup package. However, this results in the disadvantage that between the spinneret and the takeup the yarn is subjected to the tension required for fully or partially drawing the yarn. The tension under which the yarn is wound is thus still higher than the tension necessary for the drawing operation. Consequently, a godet-free spinning is possible only with such takeup systems which have an integrated godet for decreasing tension. In this respect, reference may be made to the takeup system disclosed in DE-C 23 45 898 and U.S. Pat. No. 3,861,607. In these takeup machines, the yarn loops about a grooved roll, which is part of the yarn traversing system, at an angle of 60° to 120° before advancing onto the package. This grooved roll may be operated at a circumferential speed which is greater than the circumferential speed of the package, thereby making it possible to decrease the yarn tension and to spin without godets. As a result, such yarn winding machines have become successful in the godet-free spinning process.
In the yarn winding apparatus as disclosed in German Patent DE 30 16 662, the same effect may be achieved in that the yarn advances first via a yarn traversing system, and over a smooth roll which may rotate at a higher circumferential speed than the takeup package, and finally via a second yarn traversing system to the package. Since this system uses a smooth roll, and since the yarn is looped by 180°, there is a risk of laps being formed, and other problems arising from the threading of the yarn. This applies in particular to the adjustment of the roll relative to the speed adjustment of package and yarn traversing system.
A common aspect of the known processes is that they are based on the attempt to obtain in one operating step fully or partially oriented yarns (FOY or POY), while avoiding a buildup of high yarn tensions on the package. Although a godet would be suitable for such a purpose, it entails problems of the kind noted above.
It is accordingly an object of the present invention to provide a yarn processing method of the described type, and which achieves the desired decrease of the yarn tension before the yarn enters into the takeup system, while simultaneously avoiding the disadvantages of the known godets.
SUMMARY OF THE INVENTION
In accordance with the present invention, the above and other objects and advantages are achieved in the embodiments illustrated herein by a method of processing an endless synthetic filament yarn, and which includes the steps of advancing the yarn under a relatively high tension and into contact with a feed system, and including looping the advancing yarn about at least a portion of the circumferential periphery of at least one rotating feed roll, selecting the looping angle of the advancing yarn about the at least one feed roll and the circumferential speed thereof such that the circumferential speed is greater than the speed of the yarn at the point it contacts the one feed roll, and such that the yarn slips with respect to the surface of the one feed roll and a frictional force is produced therebetween which is substantially independent of speed, and withdrawing the advancing yarn from the feed system under a relatively low tension and winding the yarn onto a rotatably driven tube to form a yarn package.
In the preferred embodiment, the winding step includes laterally traversing the advancing yarn along the length of the package and so as to form a traversing triangle.
The feed system may comprise one driven roll, or two driven rolls which are arranged one after the other, so that the yarn loops about each of the two rolls at an angle of at least about 45°. The total angle of looping is thus no less than about 90°. In any event, it should be less than 360°, and preferably less than 270°. The fact of the feed system being driven at a circumferential speed which is higher than the speed of the yarn advancing to the feed system, results in a speed difference and in slippage between the surface of the feed system and the yarn, and thus in sliding friction. It has been found, that in the case of a speed difference, the coefficient of friction of the sliding friction as a function of the degree of slippage changes to some extent abruptly and unpredictably. For this reason, godets and feed systems, as regards their frictional behavior, have conventionally been provided with suitable surfaces and wound by as many loops of yarn as necessary to avoid sliding friction. However, when the speed difference or slippage amounts to at least 3%, preferably more than 5%, and the looping angle is correspondingly adjusted in the specified range, it has unexpectedly been found to be possible to achieve a frictional behavior of the yarn relative to the surface of the feed system which corresponds practically to the frictional behavior of a body in dry sliding friction.
The frictional behavior of a body under dry sliding friction is characterized in that the coefficient of sliding friction is smaller than the coefficient of static friction, and further that the coefficient of sliding friction is independent the speed. This means that the force of resistance which is operative on a moved body, is independent of speed and therefore reproducible. In terms of the invention, this means that a constant frictional force is always operative on the yarn irrespective of the fluctuations of slippage, which leads to a precisely defined reduction of the yarn tension. Consequently, the decrease in yarn tension becomes independent of the yarn speed and thus of the relative speed of the yarn on the surface of the feed system. The importance of the present invention is to have recognized that this independence is necessary for a slip feed system which is intended to decrease the yarn tension, and further that in such a feed system there exists a range of slippage in which this independence exists. As a result, it is accomplished that while on the one hand the yarn tension is clearly reduced, the speed adjustment of the feed system is totally uncritical, as long as it is greater than a specified limit. Contrary to the known processes and the known uses of feed systems and godets, the surface is configured such that it has a small coefficient of friction relative to the yarn. The surface is therefore by no means smooth or polished, but rough or matte. Wear resistant surfaces of this kind, can be produced, for example by plasma coating with metallic oxides. Especially preferred is to also treat the yarn with fluids prior to its entry into the feed system such that the coefficient of friction is low. A coefficient of friction on the order of 0.2 is desirable. In this configuration, the Eytelwein coefficient (M=log e.sup.μ alpha, where μ is the coefficient of friction and alpha the looping angle) is not greater than 4, preferably smaller than 3.
A further important characteristic is that the feed system precedes the traversing triangle. The yarn is thus slackened above the stationary yarn guide which forms the apex of the traversing triangle. As is known, the yarn traversing system in which the yarn is reciprocated transversely of its direction of advance at a high speed and in doing so describes a traversing triangle, causes the yarn tension to fluctuate considerably with peaks in the end sections of the yarn traversing stroke system. The proposed method avoids adding the peaks in yarn tension to the high yarn tension existing after the yarn is withdrawn from the spinneret during the drawing process. Consequently, these peaks in yarn tension cannot detrimentally affect the quality of the yarn.
Preferably, the range of the overall looping angle is determined by two criteria. One criterion is an adequate and clear reduction of the yarn tension, and the other criterion is a smooth, troublefree advance of the yarn. However, the size of the looping angle has also an influence, even though not very great, on the amount of the minimum value of slippage which must be predetermined, so as to achieve the desired slip behavior. An overall looping angle of between about 90° and 270° meets this condition.
The speed difference between the speed at which the yarn contacts the feed system and the surface speed of the latter must be so small that a sliding friction develops in any event. In this process, it needs to be considered that, as it contacts the feed system, the yarn is not a solid structure, but it is capable of adapting itself by elongation or shortening to the surface speed of the feed system. It is necessary to avoid this adaptation. The minimum value of the slip will differ from surface to surface of the feed system on the one hand, and from yarn to yarn on the other. However, it has been found by experiments that the difference in speed, i.e., the slip, should be adjusted to at least 3%, preferably to more than 5%. It has further been found that in any event it is possible to obtain a very stable yarn path in the range greater than 3%, and that with a slip from 5% up to 20%, the yarn tension is no longer influenced by the surface speed of the feed system. This means that in this operational range with a slip of more than 3% to 5%, very stable operating conditions are possible with an optimal and constant reduction of the yarn tension. The consequence is that also the yarn speed and thus the yarn quality are constant and no longer influenced by the magnitude of the slip. It has thus shown that in this operational range of the slip, an overall looping angle of 90° leads to a decrease in tension of 30% upon contact of and departure from the feed system, a looping of 135° to a decrease in tension of about 40%, and a looping of 225° to a decrease in tension of 70%. This means that the decrease in the yarn tension is only dependent on the looping angle, and can therefore be regulated in a simple and reproducible manner by the adjustment of the looping angle.
A further treatment of the yarn may occur upstream or downstream of the feed system which serves, primarily the adjustment of a suitable coefficient of sliding friction. For example, the yarn may be moistened with a fluid prior to contacting the feed system.
The method of the present invention is primarily useful to withdraw the filaments of a yarn at a high speed from the spinneret and to subject same to a full or partial drawing in this process. The feed system of the present invention has in this process the advantage that no laps form on it, and that it allows high yarn tensions to be exerted on the yarn for its drawing, while a planned decrease of the yarn tension in the takeup zone is also possible.
In particular in the production of industrial yarns which distinguish themselves not only by their thickness, but also by an especially great strength, it may however be necessary to withdraw the filaments of the yarn from the spinneret, by a slipless, standard godet, i.e. a godet which is looped several times, with a high coefficient of friction, and, if need arises, to draw same in one step or in two steps between two godets. In such an event, it would be necessary to supply the yarn to the winding zone by such a slipless godet which is looped several times, with a high coefficient of friction and with the aforesaid disadvantage that laps form easily on this godet due to the low takeup tension. For this reason, the application of the feed system in accordance with the invention is also useful between such a godet and the stationary yarn guide in the yarn winding zone for purposes of decreasing the yarn tension, since this feed system allows the yarn to be withdrawn by the godet with adequate tension, and fed to the takeup system with a low tension.
It is also proposed to provide a heat treatment between the feed system and the stationary yarn guide which forms the apex of the traversing triangle, for example by a vapor-fed nozzle. Such a method permits the production of, in particular, polyamide yarns at a high speed of more than 3500 m/min. by the high-speed spinning process, and likewise polyester yarns which may be wound in this instance at speeds higher than 5000 m/min. To produce fully oriented yarns, it is recommended to provide for a tubular heater upstream of the feed system, such as is described in U.S. Pat. No. 4,902,461, note also U.S. Pat. No. 3,229,330.
The interposition of the vapor treatment provides the advantage, in particular for nylon, but also for polyester which has been spun at speeds above 5000 m/min., that the tendency to shrinkage resulting from the drawing is released, and such a considerable shrinkage occurs that a good yarn is produced when rated by its strength and shrinking properties.
Finally, it is possible and recommended to provide a so-called entanglement nozzle between the feed system and the stationary yarn guide of the traversing triangle. In this nozzle, an air jet is blown on the yarn transversely of its direction of advance, thereby effecting the formation of individual tangles distributed over the yarn length. This strengthens the coherence of the individual filaments in the yarn.
The method of the present invention is also particularly suitable for the so-called "short spinning" process. In this process, the feed system is arranged at a short distance of less than 2 meters below the spinneret. The yarn is so quickly withdrawn by the feed system that it is adequately cooled along this short distance. At the same time, a high air resistance which acts on the yarn effects, together with the residual heat remaining in the yarn, an almost complete drawing of the yarn. The speeds in this instance are above 7000 m/min.
The surprising discovery which underlies the present invention is that when the slip is increased to values not heretofore practiced, which are above 2%, and preferably however above 3%, the change in the yarn tension downstream of the godet or feed system is no longer dependent on the surface speed of the godet. Therefore, this method permits a very stable operation, since also the tendency of the feed system to cause a breakdown of the operation by filament breaks and/or lap formation is practically eliminated. The amount of the yarn tension however may be clearly and reliably determined with the looping angle. Due to the amount of slip, also the risk of laps forming on the feed system is simultaneously eliminated despite the low yarn tension, at which the yarn leaves the feed system. Thus, a considerable decrease in tension is allowed to occur. In this process, the first godet operates in the range of static friction with the advantage of a reduction of the yarn tension. The second godet effects a further reduction of the yarn tension and a steadying and stabilizing of the operating conditions. Because of the considerable reduction of tension, the method is also particularly suitable for the inclusion of the described aftertreatment processes following the draw process. Therefore, a shrinkage treatment is suggested between the feed system and the stationary yarn guide of the traversing triangle, in which the yarn is subjected to the action of heat, and/or an entanglement treatment, in which an air jet is directed on the yarn transversely to the yarn axis, thereby producing a combination between the individual filaments.
As aforesaid, the method of the present invention distinguishes itself in that it permits the reproducible process parameters to be adjusted, in particular yarn tension and yarn speed. However, while on the one hand cases are conceivable in which greatest accuracy matters, on the other hand cases are also conceivable in which, as a result of changes in the surface condition or changes of the yarn characteristic, long-term operation leads to changes in process parameters and thus also to a change in yarn properties. To eliminate this, it is further proposed to regulate the yarn tension in that the looping angle is adjusted in dependence on the measured yarn tension. The measuring device as used in the process, permits the looping angle to be adjusted at the same time, in that one of the rolls of the feed system, or a further roll preceding the feed system, is arranged for movement under the yarn tension against a spring force such that the looping angle changes along with its movement. This is a further possible embodiment. However, it is also possible to provide a measuring sensor with an adjusting device which changes the relative position of the rolls of the feed system such that the looping angle changes.
The feed system of the present invention further allows novel process variants of the already described short spinning process and the spinning process using a tubular heater to be realized. For example, the yarn may be advanced through a narrow heated table and heated to a temperature above 90° C., prior to passing through the feed system.
Whereas both the short spinning process and the spinning process with a tubular heater have in the past been affected by the disadvantage that the resulting drawn yarns are very susceptible to shrinkage and therefore create considerable problems in the winding of the yarn, the process variant of the present invention permits such shrinkage to be reduced. For example, a shrinkage treatment may be positioned between the feed system and the stationary yarn guide of the traversing triangle, and which involves directing hot or saturated vapor into contact with the advancing yarn.
A further advantageous variant of the process results for the so-called spin texturing process. Spin texturing is known from German Patent DE 26 32 082. In this process, the freshly spun and drawn yarn advances through a hot air or hot vapor nozzle into a tubular stuffer box, where it is compressed to a yarn plug.
The yarn plug is advanced under the impact of the hot air or vapor through the tubular stuffer box, withdrawn therefrom as a yarn plug and wound on a cooling roll. Before leaving the cooling roll, the yarn plug is withdrawn, which leads to considerable fluctuations in the yarn tension. Therefore, it has been difficult to subject the now-crimped yarn to a uniform entanglement treatment, since the fluctuations in the yarn tension led also to different results of the entanglement. Even the interposition of a standard feed roll between the cooling drum and the entanglement nozzle did not remedy the situation, since the feed roll transmits the fluctuating yarn tension.
The above problems associated with the spin texturing process are solved by the process of the present invention. In addition, the use of a further slipfree feed system, or in particular its yarn brake, allows to further stabilize the yarn tension.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the objects and advantages of the present invention having been stated, others will appear as the description proceeds, when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a front view of a spinning apparatus which embodies the features of the present invention;
FIG. 2 is a side view of the spinning system;
FIGS. 3-9b show modifications of the spinning system in accordance with FIGS. 1 and 2;
FIG. 10 is a diagram of the yarn tension versus the slip;
FIGS. 11 and 12 show further modifications for regulating the yarn tension;
FIG. 13 is a further modification for adjusting the yarn tension by hand; and
FIGS. 14 and 15 illustrate still further embodiments of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The embodiment illustrated in FIGS. 1 and 2 includes a spinning system for four yarns I which are each wound onto a winding tube to form a package on a common winding spindle 2. Upstream of the yarn takeup device, a traversing system 3 is arranged which reciprocates each of the yarns along its associated package. As a result of this motion, each of the yarns describes a traversing triangle between a stationary yarn guide 4 and the yarn traversing system 3.
Arranged between collecting yarn guides 5 and stationary yarn guides 4 is a feed system 7. The function of the collecting yarn guides 5 is to reduce the mutual distance between the yarns which first corresponds to the gauge of spinnerets 8, to the gauge of the packages on spindle 2. The feed system 7 extends over the overall distance of the collecting yarn guides 5, and it comprises two rolls 9 and 10 which are arranged parallel to one another and which are offset in height a distance which equals their diameter, as is seen in FIG. 2.
For reasons of clarity of illustration, FIG. 1 shows a greater offset in height, so as to be able to illustrate that there are two rolls 9, 10. The rolls are rotated in opposite directions substantially at the same circumferential speed. They are looped by the yarn at an angle alpha of at least 90°, and they have a coefficient of friction relative to the yarn of, for example, 0.2 to 0.6. The circumferential speed is higher, for example, 3% to 30% than the yarn speed. The yarn speed is determined from the geometrical sum of the constant circumferential speed of the packages and the speed of the yarn traversing system 3.
The two rolls 9, 10 of the feed system may be adapted for relative movement with respect to one another, so as to be able to thread the yarn on the winding head without contacting the godets. To this end, the rolls 9, 10 may be supported for rotation on a rotatable support plate 17 (FIGS. 9a, 9b). It is possible to drive the rolls by one motor with a gear connection, or by two independently controllable motors. Thus, it is possible to adjust the speed of the first roll 9 lower than that of roll 10, so a static friction is present on roll 9, whereas a clear sliding friction with a slip of 3% or greater exists on roll 10.
Shown in FIG. 10 is a diagram which illustrates the dependency of yarn tension (F) on the slip, which is measured in cN, and develops between feed system 7 and the yarn takeup device. Slip is here defined as the difference between the surface speed (v LW ) of the feed system 7 less the yarn speed (v F ) directly before the feed system, and divided by the mentioned yarn speed (v F ). ##EQU1## When the slip is below a certain value, e.g. less than one percent, the relation between yarn tension and slip cannot be represented practically and reproducibly. When the slip is above that value, an essentially reproducible relationship results, which demonstrates that the yarn tension is dependent on the amount of slip. Only in that range, will it show that the decrease in yarn tension or yarn tensile force is dependent on the looping angle alpha or its sum, at which the yarn loops about the driven rolls of feed system 7. However, it will show in particular that irrespective of this looping at a certain slip which is in the range of 2.5%, it is essentially no longer possible to decrease the yarn tension as the slip increases. For this reason, the operative point of the feed system is placed in a range, in which the yarn tension measured downstream of the feed system is no longer dependent on the amount of slip. There exists now a behavior under sliding friction between the yarn and the surface of the feed system, which corresponds substantially to the behavior under sliding friction in dry friction. In this manner, it becomes possible to produce packages and yarns of great uniformity and quality. On the other hand, there is no risk that filament breaks occur, and that the filaments, broken filaments, or the yarn form laps on the rolls of the feed system.
FIGS. 3-9 show modifications. These modifications relate to the regions I, II, III which are boxed in dashed lines in the drawing of FIG. 2.
FIG. 3 illustrates a modification of feed system 7. In this Figure, the feed system comprises a driven roll 10, to which the yarn advances from a freely rotatable guide roll 11. To achieve the advantages of the invention, it is necessary to adjust in this embodiment the looping angle alpha exclusively on the driven roll 10. The slip occurs exclusively on the driven roll 10. The advancing may if desired be moistened, such as by oiling the yarn, at a location upstream of the roll 10, and such that the advancing yarn has a coefficient of friction which is less than about 0.4 with respect to the surface of the roll 10. Also, a driven feed roll could be positioned upstream of the roll 10, with the feed roll having a surface speed which is substantially the same as or up to about 2% greater than the advancing speed of the yarn.
FIG. 4 illustrates a modification of the feed system which consists of two driven rolls 9 and 10. However, the first roll 9 is driven exactly at a circumferential speed which is equal to the yarn speed (v F ). It is therefore necessary to adjust on roll the looping angle alpha which is required for the desired decrease of the yarn tension or yarn tensile force. It is roll 10 whose circumferential speed is greater by the desired slip than the yarn speed or the surface speed of the preceding roll 9.
FIGS. 5 and 6 show modifications of the region II upstream of feed system 7 in accordance with the invention. In FIG. 5, a heating system is provided upstream of the feed system. This heating system may be a vapor chamber 12 as is illustrated. Accommodated in this vapor chamber, is a vapor nozzle 13, through which the yarn advances and is supplied with heated or saturated vapor. In the place of this heating system, it is also possible to use a heated plate or a straightened heated tube, through which the yarn advances without contacting it, and in which the yarn is drawn and set. Such a heated tube is described, for example, in DE 38 08 854 A1.
Illustrated in FIG. 6 is a modification of this region II with a heated godet 14 and a guide roll 15 associated thereto. The yarn loops several times about the godet. It operates at a speed which corresponds to the speed at which the yarn is withdrawn from the spinneret. The godet allows to set the withdrawn yarn at a temperature which, depending on the kind of yarn, may range between 90° and 240° C.
Subsequently, the yarn is withdrawn by the downstream feed system of FIG. 2, 3, or 4. In this instance, the surface speed of slip roll 10 is, in accordance with the desired slip (S), above the surface speed of the heated godet 14. This ensures on the one hand that the yarn is reliably withdrawn from the heated godet and does not form laps. On the other hand, however, the yarn tension or tensile force is decreased, as has been described above.
FIGS. 7 and 8 show modifications of the region III between the feed system 7 of the invention and the stationary yarn guide 4.
The modification of FIG. 7 includes an entanglement nozzle 16 in this area. In the entanglement nozzle, the yarn advances through a cylindrical passageway into which an air supply line terminates on its side. An air jet directed on the yarn interlaces the filaments of the yarn continuously or at certain intervals in the form of tangles. This results in a coherence among the filaments, which facilitates winding.
In the modification of FIG. 8, a vapor nozzle with a vapor chamber 12 and nozzle 13 takes the place of the entanglement nozzle. In the yarn duct of nozzle 13, a stream of heated or saturated vapor is directed onto the yarn. Due to the decrease of the tension which has been effected by feed system 7, such a nozzle and vapor treatment chamber allow to perform a shrinkage in a very efficient manner. To this end, a high amount of looping is selected for feed system 7, so that the yarn tension is low in the region III, and the yarn is allowed to shrink accordingly. The vapor treatment may also be replaced with a hot air treatment. As to its usefulness, the latter is dependent on the kind and material of the yarn.
FIGS. 9a and 9b show a modification of the feed system 7 in region I. In this instance, the feed system comprises two slip rolls 9 and 10. These slip rolls are supported on a rotatable plate 17. Plate 17 can be secured in a threading position where the rolls 9 and 10 do not contact the yarn. It is therefore very simple to thread the yarn with a suction gun 19 on rolls 9 and 10. In this connection, it should be noted that, absent a conveyance by the feed system, the yarn advancing from the spinneret has an undefined speed. It is also possible to withdraw the yarn slowly from the spinneret. Therefore, standard suction guns 19 with only little suction capacity will suffice to withdraw the yarn from spinneret 8 and thread it on the winding head. Only then is plate 17 rotated in direction of arrow 18 to its position shown in FIG. 9b. As a result of this rotation, the rolls 9 and 10 come into contact with the yarn. The rotation of turntable 17 may be selected such that the desired overall looping angle alpha is adjusted on both rolls 9 and 10.
Illustrated in FIG. 11 is a modification which is similar to that of the spinning apparatus of FIG. 1. To this extent, the above description of FIG. 1 is incorporated in the following description. In this modification, the roll 9 is rotatably supported at the end of a rocker arm 20 and driven. The rocker arm 20 is rotatable about an axis coaxial to the axis of roll 10. The rocker arm 20 is supported against its weight by a cylinder-piston unit 21 which is biased by a constant pneumatic pressure such that the weight is fully compensated. On its other side, the rocker arm 20 is biased by a spring 22 against the force of cylinder-piston unit 21. The tensile force of the yarn on rocker arm 20 is therefore operative against the force of the spring 22. Consequently, the rocker arm 20 swings as a function of the yarn tensile force. Also, the looping angles alpha on rolls 9 and 10 change simultaneously. At a smaller looping angle, the yarn tension becomes less so that as a matter of its tendency, spring 22 rotates the rocker arm in the direction which increases the looping angle. The reverse will occur, when the yarn tension is reduced. Thus, the rocker arm 20 with roll 9 serves as a yarn tension measuring device on the one hand, further as a device for adjusting the looping angle, and finally, at the same time, as the feed system or a part thereof in accordance with the invention. Although this system requires the movement of large masses, thereby imparting to it a certain inertia, it is however intended to regulate only long-term fluctuations of the yarn tension.
In the modification of FIG. 12, which involves the region I of FIG. 2, the feed system comprises only one roll 10 which is looped by the yarn. As in the modification of FIG. 3, this roll 10 is preceded by a freely rotatable guide roll 11 which determines the looping angle. The guide roll is supported at the end of a rocker arm 20. The rocker arm 20 is rotatable about the axis of roll 10 against the force of a spring 22. Spring 22 is arranged such that it is operative against the torque which the tensile force of the yarn exerts on the rocker arm. In this instance, the guide roll 11 acts as a measuring device for the yarn tension, but simultaneously also as a device for adjusting the looping angle alpha which decreases along with the rotation as the yarn tension becomes larger, and increases as the yarn tension becomes smaller.
The modification of FIG. 13 relates likewise to the region I of FIG. 2. In this embodiment, the roll 9 is supported on a slide which is movable in guideways parallel to the advancing yarn. The slide 24 is vertically adjustable by means of a spindle. As a result the looping angle changes. The special advantage of this embodiment is that the yarn path does not change as a result of the vertical adjustment of roll 9. Thus, also the frictional conditions on yarn guide 5 and yarn guide 4 which precede or respectively follow the feed system, remain constant.
As shown in this embodiment, the spindle can be rotated by hand. However, it is also possible to connect this spindle with a motor, and to operate the latter as a function of a tensiometer arranged upstream of the feed system in the direction of a downward movement and increase of the looping angle, when the yarn tension decreases, and in the direction of an upward movement and decrease of the looping angle, when the yarn tension increases. In this instance, it is possible to arrange the tension detector, for example, at the place or in the region of yarn guide 5 which precedes the feed system. This arrangement, also allows to change the looping angle alpha to a great extent, when the yarn tension changes little.
FIG. 14 illustrates an especially suitable combination of the method, in that the yarn advancing from spinneret 8 is first combined and then heated in the region II in a heated tube 26. Such a heated tube is shown and described, for example, in DE-A 38 08 854. The heated tube is externally heated by an electric resistance to a temperature above 90° C. The heated tube is so narrow that the yarn assumes a corresponding temperature and is drawn as a result of its frictional resistance to the air and its plasticization in the heated tube. In the heated tube, the yarn undergoes a complete or at least a partial drawing.
The yarn is withdrawn by feed system 7 from the region II encompassing heated tube 26, which is subject matter of the present invention, and then advanced to the region III, where it is treated in a vapor chamber 12 as shown in FIG. 5. As a result of this treatment, the shrinkage tendency of the yarn is decreased. This is possible, because the yarn passes through the feed system of the present invention under very little tension, and a considerable shrinkage is thereby caused in combination with the treatment in the vapor nozzle. As a result, the tendency to residual shrinkage is reduced to a tolerable measure, so that also yarn having a strong tendency to shrinkage, such as, for example, nylon yarns, can be processed and wound in this manner. It should be emphasized that a further feed system may be provided between the vapor treatment chamber and upstream of the yarn takeup device.
FIG. 15 illustrates an apparatus adapted for spin draw texturing the yarn with a simultaneous treatment by entanglement.
A bundle of filaments exits from spinneret 8, which is combined by a yarn guide. Then, the yarn advances via draw godets 27 and 28, at least one of which may be heated. The circumferential speed of the paired godets 28 is so great that the yarn is drawn between the two pairs of godets 27 and 28. Subsequently, the yarn advances to a hot air nozzle or hot vapor nozzle 29. In this hot air nozzle, the yarn is advanced by a hot air jet blown into the yarn duct, and thence into an adjacent tubular stuffer box 30. There, the yarn forms a plug 33. The air pressure at the inlet end of tubular stuffer box 30 causes the yarn to advance therethrough, and a pair of rolls 31 withdraw the yarn plug from the tubular stuffer box. The yarn plug then advances onto a cooling roll 32 and at least partially loops about same. The cooling roll 32 is rotated at a slow circumferential speed. It is porous, and an air current is sucked through the roll from the outside to the inside, thereby cooling the yarn plug 33. Subsequently, the yarn is again singled in that it is pulled out from the yarn plug. The point of exit is indicated at numeral 34, but it should be emphasized that the point of exit is not constant due to unavoidable irregularities of the yarn plug. Consequently, the tension of the advancing single yarn fluctuates.
To withdraw the yarn at the point of exit 34, a feed system 9 in accordance with the invention is used. In the illustrated embodiment, feed system 9 is looped at an angle of approximately 180°. The circumferential speed is more than 3% above the yarn speed. As a result, the yarn tension is very considerably reduced downstream of feed system 9, and the fluctuations of the yarn tension are substantially lessened. A looping feed system 35 may now follow, which is believed to result in a further steadying of the fluctuations in the yarn tension. It is however expected that in normal cases of application the feed system 9 of the present invention will suffice to achieve a uniform result in a subsequent entanglement nozzle 16, in which an air jet is blown onto the yarn transversely of its axis, which results in tangles at regular intervals. The tangles are in their shape and stability and in their intervals the more uniform, the more uniform the yarn tension. As shown in FIG. 15, a further looping feed system 36 may be arranged between yarn traversing system 3 and the entanglement nozzle. This looping feed system is intended to prevent the unavoidable fluctuations in the yarn tension, which develop in the traversing zone between stationary yarn guide 4 and the takeup package, from being transmitted into the entanglement zone. While this feed system is often advantageous to obtain a uniform entanglement result, it is unnecessary in many installations. The yarn advancing from the traversing system proceeds to the takeup package 2 via a guide roll.
In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. | A method of processing an endless synthetic yarn is disclosed, wherein the yarn is withdrawn from a spinneret, and advanced into contact with a feed system which is operated under conditions which produce slippage between the feed system and the advancing yarn. As a result, a constant frictional force is exerted on the yarn irrespective of fluctuations of other parameters, and a precisely defined reduction of the yarn tension is achieved which facilitates the subsequent winding of the yarn into a package. | 3 |
BACKGROUND OF THE DISCLOSURE
The present inventor has successfully devised and used an interior wiper for tubular goods. It is set forth first in U.S. Pat. No. 4,221,264 and also in U.S. Pat. No. 4,287,948. The two patents together show a device which is especially useful for dropping in a well during drilling procedures. It wipes the interior of the string of pipe. It can be used to clean a string of drill pipe. During drilling a well, it is necessary to circulate drilling fluid which is commonly known as drilling mud downwardly through the drill string. Ultimately, it is necessary to retrieve the drill string from the partly drilled well borehole at which time the drill string is pulled and stacked in the derrick. It is pulled typically one stand at a time, a stand being equal to three joints of pipe in ordinary circumstances. As it is pulled, drilling fluid drips from the unthreaded stand pipe and splashes on the floor. When this happens it creates a problem of slippage on the floor. This is dangerous to the rough necks who are working on the rig floor. Not only is it dangerous, it is wasteful of expensive drilling fluids. Less costly fluids are made of clay and more costly fluids are made from oil bases and additives.
Another problem relating to the spillage of drilling fluid in the rig floor derives from the pollution risk. Whether the rig is on land or at sea, when the rig flood gets dirty, there is always the chance of spillage off the rig floor either onto the surrounding land or into the body of water where the rig is located. In either instance, pollution problems can arise. Drilling mud which is spilled on a body of water may create a sheen on the surface of the water.
The device of the foregoing patents has met with very substantial success. It has been used on wells beyond count or measure. In fact, the number of wells that have been protected with this device easily number into the thousands. In other words, more than several thousands of times, a drill string has been pulled from the well borehole and the interior has been wiped. On doing this, the amount of drilling fluid splashed on the floor has been reduced.
One advantage of the present device is the effectiveness in wiping the drill pipe on the interior. There are certain disadvantages however that arise from this. For one, the device is in effect a free falling body which is dropped into the drill string. It is free falling in the sense that it is untethered and is able to fall in the pipe. Of course it does not fall in the sense of a falling rock, but rather it falls in the drill string to land on the drilling mud that is in the drill string. As an untethered and unanchored device, it is necessary to sometimes find the device and pull it from the drill string. To this end, it is made with a fishing neck at the upper end. The fishing neck features a mushroom shaped upper end which is sharpened or pointed somewhat and which has an overhanging shoulder to thereby enable a grappling device to grab the wiping device. In retrieval of the device from a well, it is often necessary to drop a fishing tool in the drill string which lands on top of the wiping device. Occasionally, the dropped fishing tool travels with sufficient speed that it bangs the interior of the pipe and damages the wiping device. Moreover, sinker bars are attached to the overshot (a grappling tool) which enables the top end of the wiping device to be grasped or held. As a further particular, the present invention is especially effective in wiping drill strings where the drill string is formed of pipe joints having internal upsets. As a generalization, joints of pipe are threaded together to define thicker threaded joints compared with the mid-points between joints. Because joints have a thicker wall, the thickness in the wall requires a surrounding shoulder which either protrudes on the interior or the exterior. It is possible to have a pipe string which is externally flush meaning that the upsets in the drill pipe form shoulders protruding inwardly. This forms an internal restriction, thereby limiting axial flow. There is also a type of pipe which has external upsets so that the interior is substantially open without restrictions or bottlenecks. It is however more common to make drill pipe with internal upsets. Thus, the device described in the previous patents has been very successful in handling internal upset pipe, wiping the bore of the pipe clean and reducing drill mud dripping on the rig floor.
The device as actually used in the field has been susceptible to tremendous damage. The damage has resulted primarily from the weight of the sinker bars attached to the grapple or overshot. Such devices can bend or destroy the upper end of the wiping device. They may strike the fishing neck and grasp it, but the structure there below is often bent or twisted. It is compressed, jamming downwardly, and thereby forming a distorted bend in the pipe and preventing movement upwardly in response to the retrieval equipment including the grapple or overshot. The present disclosure sets forth an improved upper end construction which is able to handle that type of necessary abuse in the field. Moreover, it provides an enhancing wiping apparatus. The wiping is enhanced so that the drilling fluid which accumulates on the wall of the drill pipe is wiped downwardly. This wiping mechanism is enhanced in operation and is therefore quite successful in handling all types of pipe and especially pipe having internal upsets.
The present disclosure therefore sets forth an upper end for the wiper mechanism which is able to withstand the rigors of field use. Moreover, the present disclosure is directed to a wiper construction which is easily repaired should it be inadvertently damaged. It has the fishing neck at the upper end to enable the grapple supported on a wire line to retrieve the device. It can especially withstand the impact of the grapple even when the grapple is weighted in free fall by several hundred pounds of sinker bars attached to the grapple.
SUMMARY OF THE INVENTION
Summarizing, the apparatus of the present disclosure represents an improvement over that structure which is set forth in the foregoing patents and which further includes a set of resilient wiper discs or protruding resilient wipers. The wiper elements are formed of relatively thin stock and have the preferred form of sheet material cut in a circle and notched at one or two locations in the circle to enable folding as the wiper elements are bent when passing through internal upsets in the pipe string. The upper end construction comprises a set of relatively large diameter spacers which define the requisite spacing of the wipers. The length of the spacers controls the amount of protruding wiper to assure that all the wipers do not fold over and overlap. Moreover, the spacers provide structural reinforcing so that the upper end is formed in a more rugged manner and thereby resists bending when exposed to banging and vigorous usage.
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 side view of the improved pipe wiping apparatus of the present disclosure particularly showing construction of the upper end to resist damage which occurs in use and operation;
FIG. 2 is an exploded view of the wiping apparatus of FIG. 1 showing the relative connection of the components so that the device can be readily assembled and further showing the entire system on a common centerline axis for assembly;
FIG. 3 is a perspective view of a wiper;
FIG. 4 is a perspective view of a wiper rotated by 90° ; and
FIG. 5 is a perspective view of a wiping element which has been folded as occurs during traversing of internal upset pipe.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Attention is directed to FIG. 1 of the drawings which shows the reinforced stronger upper end portion of the wiping device 10 of the present disclosure. The device 10 is the device shown in the two cited references mentioned above. It includes a type of bladder mechanism as described in those references. FIG. 1 is the structure at the upper end which is made in a different fashion to resist the banging and stress resultant from actual use so that the device lasts much longer and is able to survive the rough environment in which it is used. The upper end of the wiper apparatus identified at 10 is also shown in FIG. 2 of the drawings which is an exploded view showing the components and how they are put together or assembled.
Considering therefore FIGS. 1 and 2 jointly and proceeding from the upper end of the tool, it will be noted that the device has a fishing neck 12 constructed with an overhanging shoulder 14 adjacent to a narrow or constricted neck 16 which enables grasping with a fishing tool or some other type of grappling device. The fishing neck is constructed in accordance with an industry standard to fit within an overshot or grapple tool. It connects to an enlarged neck portion 18 which is axially hollow and drilled from the bottom. The neck 18 is internally threaded so that it will thread to a long hollow pipe 20 specifically delineated in the exploded view of FIG. 2. The pipe 20 is sufficiently long that it supports the various components in the assembled state and threads to the interior of the neck 18. This has the form of internal threads 22 which are formed for connection with the pipe 20. The pipe 20 supports all the equipment and holds it together. Going further down the structure, a lock washer 24 is also illustrated and it is included to abut a lower end of the neck 18, and is locked on top of a flat washer 26. The flat washer is used to clamp the top wiper 30. There are several wipers 30 which are spaced along the structure and they all have the same reference numeral. They look different in the drawings because they are viewed from a different perspective. This will be understood on review of FIGS. 3 and 4 jointly. The washer 26 clamps over the wiper element 30. The wiper element is formed of resilient material and has a protruding peripheral outer edge which is folded or bent during transition through the upsets on the interior of the pipe string. The wiper 30 is formed with a small central hole which is sized to fit around the pipe 20. This enables proper axial alignment of all the components when assembled as shown in FIGS. 1 and 2.
A spacer 32 is included below the wiper 30. The spacer 32 has an outer diameter that is approximately equal to that of the washer 26. This enables the wiper element to be clamped on the top and bottom faces with equal area components clamping against this resilient member. This enables the wiper 30 to flex, but it is secured so that flexure does not tear the wiper away from the supporting washer 26 or spacer 32. As will be further observed in FIGS. 1 and 2 of the drawings, the spacers are repeated at several locations, there being four spacers 32 in the illustrated and preferred embodiment. In like fashion there are four wipers 30 which are shown also in the preferred embodiment. While it is not obligatory to use four spacers and four wipers, it has been found that better wiping is accomplished with four wipers. Of particular note is the fact that the first and third wipers, counting from the top, have maximum diameters at one dimension, and the second and fourth wipers have an equal larger diameter at another dimension. The four wipers alternate in relative position with respect to the mounting pipe 20 which supports the several wipers. More particularly, the wipers are deployed so that they protrude outwardly and are able to engage the wall of the drill pipe in a fashion that will be detailed later.
The four wipers are all clamped as noted and clamping action is furnished in part by the spacers 32. The bottom spacer 32 is supported on a thrust washer 34. The washer 34 fits on the exterior of the pipe 20. The washer 34 is constructed so that it holds up the entire stack of wipers and spacers. The washer 34 seats against or bottoms against a pair of lock nuts 36 and 38, there being a split ring washer 40 between the two. The split ring washer 40 assures that the nuts 36 and 38 are under tension so that accidental unthreading is prevented. The two lock nuts 36 and 38 are threaded on the exterior of the pipe 20. They are used to connect with or anchor a resilient connective sleeve 48. The sleeve 48 is a flexible joint. An alternate form is a coil spring of the sort that is shown at the lower end of the equipment. Indeed, such a flexible joint is shown in the referenced patents of the present apparatus. A resilient sleeve of rubber like material is preferably used. It has an external form of a cylinder and it is bonded to the pipe 20. The pipe 20 preferably does not pass fully through the plug 48. Rather, the pipe is discontinuous so that there is the upper pipe section 20 previously defined and a similar but disconnected lower pipe section 50 there below. The two pieces 50 and 20 can connect at end located chain links or the like. This defines the flex joint previously mentioned so that bending can occur in this region without bending permanently the pipe 20 which would occur in the event it were continuous. The rubber sleeve 48 enables bending.
The flexible joint 48 is locked in position by a separate nut 52 at the bottom side thereof. The rubber sleeve 48 enables flexure of the tool which, when assembled, is several feet in length. A large amount of flexure is not normally encountered; rather, the flexure is only a few degrees but this is sufficient to prevent breaking the equipment when dropped in a drill string.
FIG. 2 shows the remainder of the equipment which is connected in the system. In accordance with the teachings of the two mentioned patents above, there is a buoyant chamber 66 which threads with the pipe 50. The pipe 50 is preferably a solid pipe connected to the chamber 66. Structural strength and integrity are enhanced by the use of a solid rod or pipe. In like fashion, the pipe 20 thereabove is shown to be hollow but it also can be solid. There is no need to sustain a fluid flow pathway along the pipe 20. Whether solid or hollow, strength is achieved by selecting a pipe of sufficient stiffness so that bending does not occur. The buoyant chamber 66 operates in the manner set forth in the two referenced patents, and one version of the lower part of the structure there below is set forth in detail in those disclosures. In FIG. 2, the pipe 50 threads to the top of the chamber 66, and the hollow pipe 70 threads to the bottom. This creates an open passage into the chamber 66 through the pipe 70 which is plugged by a moldable resilient plug 72. The plug 72 is blown out of the hollow pipe 70 to serve as an over pressure relief system to avoid crushing the chamber 66. A spring 74 is coiled around the pipe 70 and bears on a replaceable disc 80. The disc 80 is sized to limit travel into tool joints where tool snagging might occur. The disc 80 can be replaced. The lower most sleeve 82 is the bottom termination and it can be the same as or different from the disc 80 in size. The disc 80 and the sleeve 82 are limit devices to prevent entry into restricted passages.
In operation, the device of the present disclosure is assembled above the buoyant chamber 66 to enable a proper level of buoyancy to be obtained. Since the spacers 32 add weight, the buoyant chamber 66 can be made larger. This will counter balance the added weight. The wiping tool 10 is dropped in the drill string and the wipers 30 reach out to wipe the surface of the pipe on the interior, pushing mud downwardly as the device falls relatively down into the pipe string. The wipers 30 are kept above the level of the mud which establishes a hydrostatic head in the drill string. The wipers 30 are readily passed through the internal upsets in the pipe. This is made more clear on viewing FIGS. 3 and 4 jointly. There, the wipers are identical in construction but they are positioned 90° out of phase; this positioning enables the wipers to reach out and wipe the interior surface of the pipe so that any mud on the inside wall is forced downwardly. Moreover, the 90° rotation between adjacent wiping elements assures that there are no notches which align so that the full 360° of the interior pipe is wiped. During free fall or when floating on the column of mud in the pipe string, the wipers continue to push the mud downwardly even when the wipers pass through an upset. A portion of the wipers is bent upwardly; that bending occurs as the wipers pass through the joints in the drill pipe. Of particular importance to the present disclosure, FIG. 5 shows how they are folded upwardly. When folded in this fashion, they continue to wipe with the nether face so that mud is forced downwardly in the drill pipe. Further, the wiping action achieved by this mechanism assures continued successful operation on passing through many internal upsets. On transition through the joints, the wipers fold upwardly. It is especially important to note that the spacers 32 are sufficiently tall and the wipers are spaced sufficiently apart that one wiper does not overlap on the adjacent wiper. This might otherwise bind when passing through the internal upsets. Such binding action might otherwise occur but does not occur in this instance because the flexure of the wiping elements 30 is limited.
In operation, the device of the present disclosure is dropped into a drill string when pulling the drill string from a well borehole in which drill fluid has accumulated on the inside of the pipe. Because of buoyancy, the device floats in the column of drilling mud in the pipe. As the pipe is pulled upwardly, the device travels relatively downwardly in the drill string. When passing through the pipe, the wipers 30 force drilling fluid on the sidewall downwardly and keep the pipe relatively clean. In this motion, wiping is accomplished both in the drill pipe where it is full gage and also at the upsets where it is reduced in diameter. When passing through the upsets, the resilient wipers are bent or folded in the fashion shown in FIG. 5 of the drawings.
If the device is retrieved with a grapple or overshot, the grapple is dropped into the drill string, typically supported below 200 to 300 pounds of sinker bars, and lands on the fishing neck. When that occurs, there is the risk of bending the inside wiping device but that is markedly reduced by the incorporation of the spacers 32 deployed at the upper of the equipment. The spacers 32 particularly have a diameter sized with respect to the internal upsets through which the device 10 will pass so that there is adequate room but they are sufficient large in diameter that pounding on the upper end of the equipment does not ordinarily bend the equipment. Rather, the diameter of the spacers is correlated to the most narrow passage in the pipe string to permit use of this equipment.
While the foregoing is directed to the preferred embodiment, a scope is determined by the claims which follow. | An improved pipe wiping device is set forth which incorporates from an upper end fishing neck, a threaded connection for a central mandrel and multiple pipe wiping elements which are formed of flat resilient sheet material cut in circular fashion and having notches therein. The pipe wiping elements are alternately spaced so that the notches in the pipe wiping elements are overlapped above or below by protruding pipe wiping elements. Enlarged and elongated spacers are positioned between adjacent pipe wiping elements. The central mandrel terminates at a flexible coupling formed of resilient material or a spring. It then connects with a buoyant chamber there below to cause the device to float in the drill mud in the pipe string as the pipe string is pulled from the well borehole. | 4 |
RELATED APPLICATIONS
[0001] This application is a continuation of application of copending application Ser. No. 11/183,170, filed Jul. 18, 2005, which is a continuation of application Ser. No. 10/097,856, filed Mar. 15, 2002, now U.S. Pat. No. 6,918,732, and hereby claims the priority thereof to which it is entitled.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a changing station for sleeves of printing machines.
[0004] 2. Description of the Related Art
[0005] The operation of printing machines requires that the printing sleeves or engraved roller sleeves have to be changed. In the case of larger printing machines the printing sleeves can exhibit a weight of approximately 20 kg. The operating personnel must change these printing sleeves manually, whereby the respective sleeve mandrel inside the printing machine can be reached only by means of a ladder. Thus, such a changing of the sleeves is troublesome for the operating personnel and subject to accidents.
[0006] The object of the present invention is to provide a changing station for sleeves that makes it easier for the operating personnel to change the sleeves in printing machines.
SUMMARY OF THE INVENTION
[0007] The invention solves this problem by a combination of features, including a changing station for sleeves of printing machines, in which a lifting platform, on which the operating personnel stands for the purpose of changing the sleeves, is provided at the side of the printing machine.
[0008] Furthermore, a wagon is a component of the changing station, in which a vertically adjustable shelf with carrying mandrels for receiving the sleeves is accommodated, whereby the shelf can be coupled to the lifting platform for joint lifting and lowering.
[0009] This changing station gives the operating personnel the possibility of handling in a safe and simple manner the sleeves in a plane between the printing machine and the shelf, which exhibits carrying mandrels and is disposed in the same plane. It is especially advantageous that all sleeves can be received immediately in the changing station so that there is no need to climb the ladder with great effort after depositing each sleeve. The changing station makes it possible to change the sleeves much faster and with greater ease and without danger.
[0010] Especially advantageous designs of the changing station, according to the invention, are disclosed in the dependent claims.
[0011] It follows that the lifting platform can exhibit a front and two side protective gates, whereby at least one of the side protective gates is designed as a folding door. Thus, the safety requirements for the operating personnel are met.
[0012] The lifting platform can be raised and lowered advantageously by means of a motor-driven scissor lift.
[0013] The wagon is enclosed advantageously on three sides and open in the direction of one side, whereby the shelf receiving the carrying mandrels is oriented in such a manner in the wagon that the carrying mandrels can be attended from the open side of the wagon. The wagon can be open at the top; and the vertically adjustable shelf can be mounted in the wagon so as to be vertically adjustable by means of slide bearings.
[0014] Finally the shelf can be made of a structural steel beam, whereby this structural steel beam can be couples to the front protective gate of the lifting platform by means of a coupling mechanism. The coupling mechanism comprises advantageously journals, which engage with an opposing journal receptacle.
[0015] It is also advantageous to dispose on the front protective gate of the lifting platform additionally support brackets, against which at least one support of the shelf is braced in the coupled state.
[0016] The wagon can be mounted, according to a preferred design variant, on rollers, which can be locked by means of locking brakes.
[0017] Other details and advantages of the invention are explained in detail with reference to the embodiment depicted in the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a perspective view of the inventive changing station in different working positions; and
[0019] FIG. 2 is a perspective view of the changing station, according to FIG. 1 , at a different viewing angle and in a different working position of the respectively illustrated changing stations.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
[0021] In FIG. 2 the reference numeral 10 refers to a part of a printing machine, whereby a row of printing rollers 16 or engraved rollers 18 are disposed in the known manner around a counter pressure cylinder 14 in a support frame 12 , which is only partially shown here. The printing machine can be closed by means of folding doors 20 on the side, whereby the drawings, according to FIG. 2 and/or FIG. 1 , show the folding doors in different folding positions.
[0022] FIGS. 1 and 2 show two changing stations 30 in different positions next to the printing machine. The changing stations comprise in essence a lifting platform 32 and a wagon 34 .
[0023] The lifting platform 32 exhibits a floor 36 , which can be moved by means of a scissor lift 38 . The scissor lift 38 is moved by means of a motor, which is not shown in detail here. On the floor 36 is a front protective gate 40 and two side protective gates 42 , both of which can be folded open.
[0024] The wagon 34 can be driven on rollers 44 , whereby the rollers 44 exhibit locking brakes 46 , which are foot operated so as to lock the rollers 44 . The wagon exhibits walls 48 on three sides. Inside the walls is a shelf 50 , which is made of a welded structural steel beam and can be vertically adjusted by means of slide bearings, which are not shown in detail here. The rear side 52 of the shelf has a total of twelve mandrels 54 so that, as shown in FIG. 1 , they are accessible to the operating personnel from the open side of the wagon 34 and do not touch one another. FIG. 1 shows in the wagon depicted in the lowered position on the right hand side how a printing sleeve 56 is being removed. Below the printing sleeves, the engraved roller sleeves 58 are slid onto the mandrels 54 .
[0025] The wagon 34 can be coupled to the lifting platform 32 so that the shelf 50 can be raised and lowered together with the lifting platform. The coupling is effected by means of two journals 60 , which are disposed at the uppermost support of the shelf 50 and which can be inserted into journal receptacles 62 at the front protective gate 40 of the lifting platform 32 . Finally there are on the front protective gate 40 two support brackets 64 , which support from below the corresponding support of the shelf after the journals 60 have been coupled into the journal receptacle 62 .
[0026] Thus, as the lifting platform 32 is raised and lowered, so can the shelf 50 of the wagon 34 be simultaneously raised and lowered.
[0027] FIG. 1 shows on the right hand side how a printing sleeve 56 is being removed. Here the wagon 34 is uncoupled from the lifting platform 32 , and the shelf 50 is moved into the wagon into its lowest position. In contrast, on the left hand side of FIG. 1 , the shelf 50 of the wagon 34 is coupled to the lifting platform 32 . The shelf and the sleeves are raised together with the lifting platform so that the operating personnel can now change the sleeves. When fitting the mandrels of the shelf, one mandrel is left free, on the one hand, for the engraved roller sleeves and, on the other hand, for the printing sleeves so that the sleeves can be changed in succession in one operation by the operating personnel. The number of mandrels, depicted in the design according to FIG. 1 , is reproduced here only as an illustration. Of course, an arbitrary number of mandrels can be disposed on the shelf.
[0028] The right hand side of FIG. 2 shows a wagon 34 with the shelf 50 moved to the top, whereby a printing sleeve 56 is being removed from the shelf. On the left hand side a wagon 34 is depicted in the lowered and uncoupled position.
[0029] The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims. | The invention relates to a changing station for sleeves of printing machines with a lifting platform, disposed on the side of the printing machine, and with a wagon, in which a vertically adjustable shelf with carrying mandrels for receiving sleeves is received, whereby the shelf can be coupled to the lifting platform for joint lifting and lowering. | 1 |
This is a continuation-in-part of copending application Ser. No. 07/920,122 filed on Jul. 24, 1992.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a machine used to stretch, or tenter, a fabric, web or film in a direction transverse to that in which it is being conveyed through a treatment zone, such as a process oven, or to prevent the fabric, web or film from shrinking in a transverse direction as it is being conveyed through such a zone. Specifically, the present invention is a tentering machine which includes means for reducing or eliminating longitudinal distortion during tentered processing.
2. Description of the Prior Art
Tentering machines are well known in the art. Generally, these machines include pin-plates or clamps which grasp the opposite edges of the fabric, web or film to be stretched in a widthwise, or transverse direction, or to prevent their shrinking in such a direction.
The pin-plates or clamps may convey the fabric through a stretching, or tentering, zone, where they, while grasping opposite edges of the fabric, are conveyed along divergent tracks. Both before and after the tentering zone, the pin-plates or clamps on opposite sides of the fabric may proceed in parallel directions. Alternatively, the pin-plates or clamps may be conveyed only along parallel tracks so that they may prevent shrinkage from occurring in a treatment zone.
The pin-plates or clamps are driven about a pair of endless-loop paths which are adjacent to and face one another. In the tentering machines of the prior art, they are commonly attached firmly to a drive chain, which may describe an endless-loop path within that followed by the pin plates or clamps.
The tentering zone, then, is between the pair of endless-loop paths around which the pin-plates or clamps are conveyed. Initially, those on each endless-loop path grasp the opposite edges of the fabric to be tentered and may be conveyed in directions parallel to one another. In the tentering zone, they may proceed along divergent paths stretching the fabric in a widthwise direction while conveying the fabric longitudinally therethrough, or they may remain travelling in parallel directions simply to prevent shrinkage. Finally, upon exiting from the tentering zone, they may again be conveyed in directions parallel to one another, if they have diverged, before releasing the fabric.
If the fabric, web or film elongates in a direction parallel to its motion while tentered, the rigid spacing between adjacent pin-plates or clamps in prior-art tentering machines, where they are firmly attached to the drive chain, may permit distortion. Some manufacturers have attempted to overcome this disadvantage by attaching the pin-plates or clamps to the drive chain using drive pins in slotted holes, but this limits the web elongation to the length of the slot. In addition, web driving force is lost when the drive pin leaves the end of the slot.
Other manufacturers have added springs to the drive slot to maintain drive force, but such an expedient limits web elongation even more seriously.
The present invention supplies a solution to these disadvantages in the tentering machines of the prior art by including means whereby pin-plates or clamps may be driven from a chain in a manner which permits considerable web elongation without loss of driving force. In addition, the means of the present invention permits the direction of motion of the entire line to be reversed without modification or loss of function.
SUMMARY OF THE INVENTION
The present invention provides a means for driving the pin-plates or clamps in a tentering machine while allowing for a considerable rate of stretch in the tentered fabric, web or film.
In its broadest form, the present invention is a tentering machine for conveying a fabric, web or film through a treatment zone and either stretching it in a widthwise direction, transverse to that in which said fabric, web or film is being conveyed through said tentering machine, or preventing it from shrinking in that direction.
The tentering machine includes a first conveyor track and a second conveyor track, which take the form of endless closed loops adjacent to and facing each other between which the fabric, web or film to be stretched may be conveyed. The first conveyor track may have a section of predetermined length which diverges from a corresponding and facing section on the second conveyor track, or the facing sections of the first conveyor track and the second conveyor track may be parallel to one another for their entire lengths. The first and second conveyor tracks each have a guide means extending around their closed-loop forms.
The tentering machine also includes a first plurality of fabric edge holders and a second plurality of fabric edge holders. Each fabric edge holder includes an edge holding means, means for engaging with the guide means on the first or second conveyor tracks, and means for being driven around the first or second conveyor track. The first plurality of fabric edge holders is disposed on the first conveyor track, and the second plurality of fabric edge holders is disposed on the second conveyor track. Each fabric edge holder is slidingly directable about its respective conveyor track. The means for engaging with the guide means on the first or second conveyor track on each fabric edge holder fits into and cooperates with the guide means to direct the fabric edge holders around their respective conveyor tracks.
The tentering machine further includes a first drive means and a second drive means. The first drive means is associated with the first conveyor track and the second drive means is associated with the second conveyor track. Each drive means is operable to drive the first and second pluralities of fabric edge holders about their respective conveyor tracks at a common speed.
The first and second drive means each have a plurality of elongated resilient, spring-like means extending therefrom for a predetermined length to an end point for driving individual fabric edge holders of the first and second pluralities of fabric edge holders about their respective conveyor tracks. These resilient, spring-like means act upon the means for being driven on the fabric edge holders, but are not fixedly connected thereto. By extending from the first and second drive means, the resilient, spring-like means drive individual fabric edge holders of said first and second pluralities of fabric edge holders about their respective conveyor tracks, when the first and second drive means are operated.
A specific embodiment of the present invention will now be described in more complete detail, with reference frequently being made to the figures identified as set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of a tentering machine which may include the compliant drive link of the present invention.
FIG. 2 is a detailed and enlarged plan view of a portion of a tentering machine showing the compliant drive link thereof.
FIG. 3A is a plan view of a pin-plate which may be used as the edge holding means on the fabric edge holders of a tentering machine.
FIG. 3B is a side view of the pin-plate illustrated in FIG. 3A.
FIG. 4 is a side view of a clamp which may be used as the edge holding means on the fabric edge holders on a tentering machine.
FIG. 5 is a schematic view of a chain positioner, which may be included in the tentering machine of the present invention.
FIG. 6 is a detailed and enlarged plan view of a portion of the tentering machine having a chain positioner shown in FIG. 5.
FIG. 7 is a cross-sectional view taken through the conveyor track and chain positioner of the tentering machine taken as indicated by line 7--7 in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the several figures, FIG. 1 presents a schematic plan view of a tentering machine which may include the compliant drive link of the present invention. The tentering machine 10 includes a first tentering means 12 and a second tentering means 14. A fabric 20 is conveyed by the tentering machine 10 through the space between the first tentering means 12 and the second tentering means 14 in the direction of the arrows thereon, or from left to right in FIG. 1. While being so conveyed, the fabric 20 may be stretched in a widthwise direction, that is, in a direction transverse to that in which it is being conveyed through the tentering machine 10.
The first tentering means 12 and the second tentering means 14 each include an endless conveyor track, not shown in FIG. 1, about which a plurality of fabric edge holders are conveyed. The fabric edge holders convey the fabric 20 to be tentered through the space between the first tentering means 12 and the second tentering means 14 by grasping the opposite lateral edges thereof. The fabric edge holders, in turn, are driven about the endless conveyor tracks by endless drive chains which include the compliant drive links of the present invention extending therefrom and engaging the fabric edge holders. The endless drive chains may form an endless loop within the endless conveyor track on each of the first tentering means 12 and second tentering means 14.
In the tentering machine 10 shown in FIG. 1, the first tentering means 12 and the second tentering means 14 each include three corresponding sections. In the first, or inlet, section 22, the first tentering means 12 and the second tentering means 14 diverge from one another. Once the fabric 20 is picked up in the inlet section 22, this divergence either stretches the fabric 20 in a widthwise direction, or simply places it under a tension sufficient to render it taut between the first tentering means 12 and the second tentering means 14.
Having been conveyed through the input section 22, the fabric 20 enters the treatment section 24. As shown in FIG. 1, the first tentering means 12 and the second tentering means 14 are parallel to one another in the treatment section 24, and prevent the fabric 20 from shrinking in a widthwise direction during the heating or other treatment applied thereto in that section.
Finally, after being treated in some fashion, the fabric 20 enters the outlet section 26. As shown in FIG. 1, the first tentering means 12 and the second tentering means 14 converge toward one another in the outlet section 26. This convergence reduces the tension widthwise across the fabric 20, so that it may be easily removed from the tentering machine 10 at the end of the outlet section 26.
Turning now to FIG. 2, one is presented with a detailed and enlarged plan view of a portion of the tentering machine 10 of the present invention showing the compliant drive link 52 thereof. Specifically, the portion shown is a portion of the first tentering means 12. A portion of a conveyor track 30, and a portion of a drive chain 50, including several chain links 70, are shown. From a plurality of chain links 70, elongated compliant drive links 52 extend toward projecting members 72 extending upward from fabric edge holders 32.
The fabric edge holders 32 are depicted in FIG. 2 as being substantially flat plates. As implied in the preceding paragraph, a projecting member 72 is on the top surface of each fabric edge holder 32. On the bottom surface of each fabric edge holder 32 are two cam-followers 74 projecting downwardly therefrom into endless guide slot 34, by which means the fabric edge holder 32 is guided about conveyor track 30.
As shown in FIG. 2, each fabric edge holder 32 is driven in the direction of the motion of the drive chain 50 by a compliant drive link 52. The drive chain 50 is moving from left to right in FIG. 2, as indicated by the arrow. The compliant drive links 52, in turn, move fabric 20 from left to right through their contact with fabric edge holders 32. Without the compliant drive link mechanism, frictional drag along guide slot 34 would cause distortion near the edges of the fabric 20 being tentered. The compliant drive links 52, designed as leaf springs, apply sufficient force to each fabric edge holder 32 to overcome friction in the guide slot 34. It may be readily observed that, should the need arise, the drive chain 50 and fabric 20 may be driven in either direction. When reversed, the compliant drive links 52 engage with the projecting member 72 on the top surface of the next fabric edge holder 32 in line.
If and when the fabric 20 stretches lengthwise during tentering, the separation between adjacent fabric edge holders 32 is permitted to increase by the design of the present invention. This eliminates the distortion or bowing of the fabric commonly observed during the use of prior-art tentering machines. The compliant drive links 52 permit increased fabric edge holder 32 spacing. The compliant drive link 52 force may be selected by varying the spring constant of the compliant drive link 52.
Where there is a considerable amount of lengthwise stretching in the tentered fabric 20, the present invention permits a fabric edge holder 32 to overrun one compliant drive link 52 and to be picked up by the next compliant drive link 52 in line. This may be seen in FIG. 2 in fabric edge holder 76, one compliant drive link 52 is about to slip over projecting member 72 because of the separation between fabric edge holder 76, and the one to its right. However, should this occur, fabric edge holder 76 will continue to be driven by the next compliant drive link 52 in line.
In short, in order for the spacing between adjacent fabric edge holders 32 to change in response to elongation of the tentered fabric 20, a force exceeding that due to static friction in the guide slot 30 must be provided. In the absence of the compliant drive link, when an adequate force is present, the spacing between fabric edge holders 32 increases suddenly and jerkily until it is halted by tension in the fabric 20. This results in the fabric 20 being processed in a highly erratic manner. The compliant drive link 52 of the present invention permits smooth fabric elongation over the design range, while retaining the ability to operate in either direction, and to tolerate and recover from system jams. It also provides a simplicity of design which keeps fabrication and maintenance costs low.
The compliant drive line 52 force may also be varied, or adjusted, during fabric processing by moving the drive chain 50 relative to the conveyor track 30. Specifically, by varying the distance by which the drive chain 50 is separated from the conveyor track 30, the leverage applied by the compliant drive links 52 to the projecting members 72 on the fabric edge holders 32 may be varied. The smaller the separation, the greater will be the leverage.
A means by which this separation may be varied is shown in FIG. 5, which shows, in a schematic view, a portion of a conveyor track 30 having an endless guide slot 34. Several fabric edge holders 32, each having a projecting member 72, are disposed on the conveyor track 30.
For the sake of simplicity and clarity, chain links 70 and compliant drive links 52 are not shown in FIG. 5. Drive chain 50, however, is disposed around and extends between a driver sprocket 102 and an idler sprocket 104, the former of which is positively driven to set the drive chain 50 in motion. A portion of the drive chain 50 extends substantially parallel to the conveyor track 30.
On that portion of the drive chain 50, which is also closest to the conveyor track 30, a chain positioner 106, having a longitudinal channel 108 through which the drive chain 50 is constrained to pass, is disposed and is also substantially parallel to the conveyor track 30. The chain positioner 106 is movable relative to the conveyor track 30, so that the distance separating it from the conveyor track 30 may be changed. The drive chain 50 itself, constrained to run through the channel 108 of the chain positioner 106, is in this way moved toward or away from the conveyor track 30, as desired, so as to change the effective length of the compliant drive links 52 extending therefrom, the effective length being the length along a compliant drive link 52 from the drive chain 50 to the point which contacts projecting member 72 on a fabric edge holder 32. A movable tensioner sprocket 110 may be used to remove any slack in the drive chain 50, once the chain positioner 106 has been placed and secured in a desired position.
As suggested by the arrows in FIG. 5, the chain positioner 106, which is of an integral structure, has two ends 112, each of which may be locked into a fixed position. As a consequence, the two ends 112 may be separately moved toward or away from the conveyor track 30, so that the chain positioner 106 may be disposed at either a slight angle to the conveyor track 30, or parallel thereto, at relatively great or small amounts of separation. In this way, the compliant drive link 52 force on a given fabric edge holder 32 may gradually increase or decrease, or remain at a relatively large or small constant value, as it progresses through the tentering machine 10.
A more detailed view of a section of chain positioner 106 and conveyor track 30 is given in FIG. 6. The distance "A" between the chain positioner 106 and the conveyor track 30 is that which may be varied by moving the chain positioner 106. As before, fabric edge holders 32 are conveyed upon the conveyor track 30, and are guided therearound by means of cam-followers 74 on their undersides. The cam-followers 74 are inserted into and remain within the endless guide slot 34, which extends around the entire conveyor track 30.
Projecting members 72 extend upward from each fabric edge holder 32. Compliant drive links 52, attached to and extending from the drive chain 50, drive the fabric edge holders 32 through their contact with projecting members 72. The closer the chain positioner 106 is to the conveyor track 30, that is, the smaller "A" is, the smaller is the effective length (length from drive chain 50 to point of contact with projecting member 72) of compliant drive link 52, the greater is the amount of leverage obtained from compliant drive link 52.
The compliant drive link 52 may be attached to the link plates 114, which comprise each link of the drive chain 50, and connect each of its rollers 116 to the next.
FIG. 7 is a cross-sectional view taken as indicated by line 7--7 in FIG. 6 and showing the chain positioner 106 in greater detail. The chain positioner 106 may comprise a base 118 and two guide bars 120. The rollers 116 of the drive chain 50 are held in an upright position by the guide bars 120, and cannot be twisted from such an orientation by the torque of the compliant drive link 52. Further, the rollers 116 roll between the guide bars 120 of the chain positioner 106 keeping friction low. By moving the chain positioner 106 relative to the conveyor track 30, the effective length of the compliant drive link 52 may be varied, the effective length being measured from the link plate 114 to the point on the compliant drive link 52 which contacts the projecting member 72 on the fabric edge holder 32. The shorter the effective length, the greater the leverage obtained from the compliant drive link 52, and vice versa.
The chain positioner 106 allows one to change the distance separating the drive chain 50 and the conveyor track 30 in response to changing conditions in the web being processed. For example, by decreasing the distance, an increased driving force for correcting web bow or skew which may occur during processing may be obtained without compromising the ability of the tentering machine 10 of the present invention to accommodate web stretch.
Any means my be used to move the chain positioner 106, such as the lead screw, the eccentric, or the scissors. Overall, the fabric edge holders 32 and their conveyor track 30, and the drive chain 50 with its driver sprocket 102, idler sprocket 104 and tensioner sprocket 110 are attached to a common mounting plate. The chain positioner 106 is moved with respect to this common plate to vary the spacing between the drive chain 50 and conveyor track 30.
Edge holding means of the prior art, as shown in FIGS. 3A, 3B and 4, may be used on the fabric edge holders 32 of the present invention. In FIGS. 3A and 3B are shown a pin-plate of the variety commonly used in the prior art. Such a pin-plate 80 could form a part of the fabric edge holder 32 of the present invention.
FIG. 3A shows a plan view of such a pin-plate 80. Along an edge of the pin-plate 80 is disposed a plurality of pins 82 inclined in the direction in which the fabric, web or film is to be tentered. The pins 82 may form one or more rows along the edge of the pin-plate 80. FIG. 3B shows a side view of pin-plate 80 and makes clear the inclined orientation of the pins 82.
FIG. 4 is a side view of a clamp 90 which may be used on fabric edge holders 32 instead of a pin-plate 80. The clamp includes a supporting plate 92 and an arm 94 projecting above the supporting plate 92. A pressing vane 96 is pivotally secured to the arm 94 through the medium of shaft 98. Fabric 20 is clamped between supporting plate 92 and pressing member 100. Tension across fabric 20 acts to keep clamp 90 secured. Suitable means, not part of the present invention, act upon clamp 90 to grasp and release fabric 20 before and after the stretching operation, respectively.
Clearly, modifications to the above would be obvious to anyone skilled in the art, yet would not bring the device so modified beyond the scope of the appended claims. | A tentering machine having a compliant drive link allows for a considerable rate of stretch in a tentered fabric, web or film without the distortion or bowing frequently observed with the tentering machines of the prior art. The tentering machine includes two conveyor tracks adjacent to and facing one another, each conveyor track having a number of fabric edge holders slidingly directable thereabout. A fabric, web or film, grasped on opposite edges by the fabric edge holders, is conveyed thereby through the tentering machine in the space between the two conveyor tracks. Widthwise stretching occurs where the conveyor tracks of the tentering machine have sections on each side of the fabric which diverge from one another, while the two conveyor tracks may be parallel to each other on the two sides of the fabric in applications where prevention of shrinkage is of interest. The fabric edge holders on each conveyor track are run at a substantially common speed by drive chains. Elongated, spring-like compliant drive links extend from the drive chains to the fabric edge holders, but are not connected thereto. The compliant drive links allow adjacent fabric edge holders to move relative to one another, permitting a considerable rate of stretch without the distortion or bowing of the fabric, web or film observed during the use of prior-art tentering machines. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for winding and conveying a knitted fabric produced in a knitting machine, particularly a circular knitting machine.
As is well known in the art, a circular knitting machine has an upright needle cylinder or cylinders carrying vertical knitting needles therearound. As the needle cylinder or cylinders rotate, the knitting needles are reciprocated vertically to knit a fabric of cylindrical shape. The fabric thus knitted is fed downward and hangs or depends in a space below the needle cylinder. The depending fabric is passed between a pair of nip rolls to be flattened and then wound around takeup shafts that are aligned horizontally and have confronting opposite ends. The takeup shafts are normally disposed with the opposite ends in abutting contact and rotated to wind the fabric therearound into a roll. When the fabric has been wound up to a full size, it is cut from the trailing part of the knitted fabric and the takeup shafts are pulled outwardly away from each other so that the roll is released and placed on a movable stand having wheels, to be conveyed out of the knitting machine.
The above described type of apparatus for winding a knitted fabric into a roll is disclosed in Japanese Patent Publication No. Hei-1-59372 published Dec. 18, 1989.
In this known knitted fabric winding apparatus, it is necessary to cause a starting end of the knitted fabric to be gripped between the opposite inner gripping ends of the takeup shafts by shifting the shafts toward each other, before the takeup shafts are driven in rotation to start the winding operation. Because the starting end portion of the knitted fabric is hanging downwardly and the inner gripping ends of the takeup shafts are caused to advance inwardly toward the hanging starting end portion, the operation of gripping the starting end portion between the inner gripping ends of the takeup shafts is not carried out reliably.
In order to facilitate the gripping of the starting end portion of the fabric, the inner gripping ends of the takeup shafts are formed with slanted end faces, respectively, which mate with each other to hold the fabric therebetween. The slanted end faces serve to thrust the hanging fabric toward the center axis of the takeup shafts, as the takeup shafts are shifted toward each other. The slanted formation of the inner mating ends of the takeup shafts, however, tends to cause the inner gripping end portions of the takeup shafts to be transversely deflected so as to take offset positions relative to the center axis of the shafts at the instant of gripping the fabric starting end portion, because of force components transverse to the center axis, produced by the slanted end faces. This tends to cause a misgripping and a damage on the fabric.
In the known circular knitting machine, a roll of the knitted fabric prepared in the manner described above is dropped onto a movable stand and conveyed out of the knitting machine as stated before. This is carried out manually and therefore the operation is inefficient. Furthermore, the dropping of the roll imparts a shock to the roll and sometimes causes a damage to the roll.
SUMMARY OF THE INVENTION
The main object of the present invention is to provide an apparatus for winding and conveying a knitted fabric from a knitting machine, wherein the gripping of the starting end of the knitted fabric can be reliably carried out by the inner gripping ends of a pair of takeup shafts without giving rise to misgripping and damage to the fabric
An additional object of the present invention is to provide an apparatus of the above kind, wherein the prepared roll of the knitted fabric can be received without shock and conveyed efficiently out of the knitting machine.
According to the present invention, there is provided an apparatus for winding and conveying a knitted fabric produced in a knitting machine, having a pair of horizontally aligned takeup shafts disposed below said knitting machine to wind therearound the knitted fabric which is fed downwardly from the knitting machine, into a roll of the knitted fabric, said takeup shafts having opposite inner gripping ends which are normally thrust against each other to grip therebetween a lower starting end of the knitted fabric, said takeup shafts being shiftable outwardly away from each other and out of the roll formed therearound to release the roll, said apparatus comprising: knitted fabric insertion means provided at one side of said takeup shafts so as to be extendable into, and retractable out of a region in which said gripping ends of the takeup shafts confront each other, said insertion means having a fabric thrust arm on a free distal end thereof; drive means acting on the takeup shafts to shift the same toward and away from each other; actuator means coupled to said knitted fabric insertion means to extend and retract the same, said actuator means being operable to extend the insertion means so as to push said fabric thrust arm into said lower starting end of the fabric, thereby to thrust a portion of said starting end into a gap between said gripping ends of the takeup shafts which are being moved into confrontation with each other, whereby the starting end of the fabric is gripped by the gripping ends preparatory to the winding of the fabric around the takeup shafts; means for cutting a trailing part of the fabric from the roll; and means for conveying the roll out of the knitting machine
The present invention will become more apparent from the following description of preferred embodiments thereof taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view illustrating the whole construction of a circular knitting machine using the present invention;
FIG. 2 is an elevational view, on an enlarged scale, of a knitted fabric winding apparatus incorporated in the knitting machine shown in FIG. 1;
FIG. 3 is a top view thereof;
FIG. 4 is a side view illustrating one side of a stand frame;
FIG. 5 is a right-side view thereof;
FIG. 6 is an enlarged fragmentary view to explain the operation of some machine components shown in FIG. 4;
FIG. 7 is a sectional view of a portion of a takeup shaft incorporated in the knitted fabric winding apparatus;
FIG. 8 is a left-side view thereof;
FIG. 9 is a side view to explain the mode of operation of the takeup shafts;
FIG. 10 is a fragmentary view of a portion of FIG. 9;
FIG. 11 is a sectional view, on an enlarged scale, of the knitted fabric gripping members of the takeup shafts;
FIG. 12 is a sectional view taken along the chain line XII--XII of FIG. 11;
FIG. 13 is a view illustrating a knitted-fabric insertion link mechanism of the knitted fabric takeup apparatus;
FIG. 14 is a top view, on an enlarged scale, for explaining the mode of operation of free end portions of the takeup shafts;
FIG. 15 illustrates an expanded state of the knitted fabric insertion link mechanism;
FIG. 16 is a side view, on an enlarged scale, for explaining the mode of operation of the insertion link mechanism;
FIG. 17 is a perspective view for explaining the same operation thereof;
FIG. 18 is a view for explaining the operation of the free end portion of the insertion link mechanism;
FIG. 19 is an exploded perspective view of the insertion link mechanism;
FIG. 20 is an elevational view of a fabric cutting mechanism;
FIG. 21 is a plan view of the fabric cutting mechanism shown in FIG. 20;
FIG. 22 is a perspective view of the fabric cutting mechanism of FIG. 20;
FIG. 23 is an enlarged perspective view showing major portions of the fabric cutting mechanism;
FIG. 24 is a perspective view showing a cutter unit of the fabric cutting mechanism;
FIG. 25 is a perspective view of a slider;
FIG. 26 is a perspective view showing a raised state of a fabric conveying device;
FIG. 27 is a perspective view showing a lowered state of the fabric conveying device;
FIG. 28 is an enlarged elevational view showing major portions of the fabric conveying device;
FIGS. 29 through 32 are views showing successive operational states of the fabric conveying device;
FIG. 33 is an elevational view showing a modification of the fabric conveying device;
FIG. 34 is a perspective view showing a further modification of the fabric conveying device;
FIGS. 35, 36 and 37 are views showing successive different steps in the operation of the fabric conveying device shown in FIG. 34;
FIGS. 38, 39 and 40 are views showing successive different steps in the operation of another modification of the fabric conveying device; and
FIG. 41 is an elevational view showing still another modification of the fabric conveying device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention will now be described below.
Referring to FIG. 1, a circular knitting machine shown has a plurality of legs 1 forming a base frame of the knitting machine, and a supporting frame 2 is securely mounted on the legs 1 through a disk-shaped machine stand 3. Another supporting frame 2a is further securely mounted on the supporting frame 2 through a frame 3a, and a conventional needle cylinder c is rotatably supported within the frames 2 and 2a. The needle cylinder c is formed with a multiplicity of vertical grooves into which knitting needles are fitted, respectively, and vertically slid by means of cam mechanisms (not shown). A conventional dial mechanism d is mounted immediately above the needle cylinder c in such a way that it rotates in synchronism with the cylinder c. Furthermore, conventional dial needles are provided for sliding movement by dial cams in relation to the operation of the knitting needles. Conventional yarn feeding devices e are mounted above the dial mechanism d. A pair of supporting members 19 depend from a rotary member in the machine stand 3 above the legs 1, and a knitted fabric rolling or winding device H for winding the tubular knitted fabric knitted by the knitting machine is provided between the pair of supporting members 19.
Referring particularly to FIGS. 2 and 3, the knitted fabric winding device H will be described in detail hereinafter. A pair of stand frames 4 are disposed in opposing relationship with each other below the needle cylinder c, and a guide rail 5 is mounted on the upper surface of each stand frame 4 so as to extend horizontally in alignment with each other. As best shown in FIG. 4, adjacent to the ends in the longitudinal direction of the guide rail 5 are provided bearings 6, respectively, and the both ends of a lead screw 7 are supported by these bearings 6 in such a way that the lead screw 7 extends in parallel with the guide rail 5. Furthermore, as best shown in FIG. 5, a pulley 7a is securely attached to one end of the lead screw 7 and is directly coupled to the output shaft 8a of a drive motor 8, such as a stepper motor, through a power transmission belt 9 such as a timing belt. The drive motor 8 is pivoted with a pivot pin 10 to the side wall of each stand frame 4 in such a way that it can adjust the tension of the transmission belt 9 by means of an adjusting screw rod 11.
A slider 12 is threadedly mounted on the lead screw 7 in such a way that it is guided by the guide rail 5 to move in the axial direction. One end of an engaging arm 13 is vertically swingably pivoted by means of a pivot pin 14 to the upper surface of the slider 12. Furthermore, as best shown in FIG. 6, the other end of the engaging arm 13 is in the form of a bifurcated engaging portion 13a adapted to engage with a flange 20a of each of takeup shafts 20 to be described hereinafter. A rocker lever 15 is swingably pivoted with a pivot pin 16 to the slider 12 adjacent to the engaging arm 13 in such a way that one end of the rocker lever 15 can push an engaging lug 13b extended integrally from the engaging arm 13. The other end of the rocker lever 15 is connected through a transmission cable 18 to an actuator 17 (FIG. 4) such as an air cylinder mounted on a base of the stand frame 4.
Referring back to FIGS. 2 and 3, the takeup shafts 20 which, for instance, are splined, are supported in parallel with the lead screw 7 between the pair of supporting members 19 depending from said rotary member in the machine stand 3 in such a way that each splined takeup shaft 20 can slide in the axial direction and rotates intermittently by a ratchet mechanism (not shown).
Referring next to FIGS. 7 and 8, the flange 20a at one end of each takeup shaft 20 is so formed as to define a circular groove 21 and, as described above, the bifurcated engaging portion 13a of the engaging arm 13 engages with and disengages from the flange 20a. A cover 22 is attached over the outer surface of each supporting member 19 and is spaced apart by a suitable distance therefrom so as to define a space between them. A lock member 23 is vertically slidably fitted into this space and is biased by a coiled spring 24 so that the upper end of the lock member 23 can engage with a peripheral groove 20b of the takeup shaft 20.
More specifically, an engaging hole 25 made up of continuously formed small- and large-diameter holes 25a and 25b is formed in the top portion 23b of the lock member 23, and the peripheral groove 20b of the takeup shaft 20 engages with the small-diameter hole 25a of the engaging hole 25 under the force of the coiled spring 24. As best shown in FIG. 4, an actuator 26 such as an air cylinder is vertically mounted on the vertical side wall of the stand frame 4 below the lock member 23. The output shaft 26a of the actuator 26 is adapted to upwardly push the lower end 23b of the lock member 23 against the force of the coiled spring 24, thereby disengaging the small-diameter hole 25a of the engaging hole 25 from the peripheral groove 20b of the takeup shaft 20.
Referring to FIGS. 11 and 12, a movable abutting member 27 made of an elastomer such as a synthetic resin or rubber is attached to the free end of one takeup shaft 20 in such a way that it projects outwardly under the force of a coiled bias spring 28. An elastic member 29 made of a synthetic resin or rubber is attached to the free end of the other takeup shaft 20 in opposing relationship with the free end of the one takeup shaft 20 for engagement with the movable abutting member 27. Therefore, as shown in FIG. 14, the movable abutting member 27 and the elastic member 29 cooperate to clamp an end portion of the knitted fabric W as will be described in more detail hereinafter.
As shown in FIGS. 2, 13 and 15, along a vertical side of one leg 1 and adjacent to the position at which the free ends of the takeup shafts 20 engage with each other, a first longer lever 30 and a second shorter lever 31 are pivoted at the lower ends thereof to the leg 1 with pivot pins 32 and 33, respectively. The upper end of the second lever 31 is connected with a pin 36 to one end of a third lever 34 while the upper end of the first lever 30 is also connected with a pin 35 to the third lever 34 at a point spaced apart by a predetermined distance from the pin 36 toward the other end of the third lever 34 which in turn is pivoted with a pivot pin 38 to one end of a supporting lever 37. The other end of the supporting lever 37 is pivoted with a pivot pin 40 to one end of a fabric thrust arm 39 which serves to thrust and insert a portion of the knitted fabric W between the takeup shafts 20 as will be described in more detail hereinafter. As best shown in FIGS. 16 and 18, the fabric thrust arm 39 has an abutment portion 39a adapted to abut against a shoulder 37a of the supporting lever 37 by its own weight. The fabric thrust arm 39 is permitted to rotate in a counterclockwise direction as viewed in FIG. 16 only during a return as will be described later. As shown in FIG. 15, an actuator 41 such as an air cylinder is mounted horizontally on the leg 1 and its output shaft 41a is connected to the first lever 30 at a position spaced apart by a predetermined distance from the lower end toward the upper end thereof. The levers 30, 31, 34 and 37 constitute a knitted fabric insertion mechanism.
An end portion of the knitted fabric W which has been knitted and is hanging is clamped between the movable abutting member 27 of one takeup shaft 20 and the elastic member 29 of the other takeup shaft 20 in a manner to be described below. When the output shaft 41a of the actuator 41 is extended, the first and second levers 30 and 31, which are drivingly connected to the output shaft 41a are forced to rotate about the pins 32 and 33, respectively, in a clockwise direction in FIG. 15 so that the supporting lever 37 and the web thrust arm 39 on the third lever 34 are forcibly displaced to the right in FIG. 15. As a result, the fabric thrust arm 39 together with an end portion of the knitted fabric W is forced to be inserted between the abutment member 27 and the elastic member 29 of the takeup shafts 20 so that as shown in FIG. 17, a portion Wa of the lower end portion of the knitted fabric W is projected, assuming a form of a triangle. In this manner, the triangular portion Wa of the knitted fabric W is inserted between the abutment member 27 and the elastic member 29 and is frictionally clamped therebetween when the takeup shafts 20 move toward each other.
When the output shaft 41a of the actuator 41 is retracted, the first and second levers 30 and 31, which are drivingly connected to the output shaft 41a, are caused to rotate about their pins 32 and 33, respectively, to their initial positions shown in FIG. 13 so that the third lever 34 is also returned to its initial position. In this case, as shown in FIG. 18, only in the return stroke described above, the fabric thrust arm 39 is permitted to rotate in the counterclockwise direction as shown in FIG. 18 to clear the takeup shaft 20.
The mode of operation of the embodiment with the above-described construction will now be described below.
Both of the stand frames 4 are the same in construction and in the mode of operation and therefore a description of one will suffice for both.
When the knitted fabric W is to be wound or rolled, the actuator 17 shown in FIG. 4 is energized whereby the transmission cable 18 pushes the rocker lever 15 to permit downward movement of the engaging arm 13 so that its engaging portion 13a engages with the flange 20a of each takeup shaft 20.
Then the drive motor 8 is energized to rotate the lead screw 7 through the transmission belt 9 so that the slider 12, which is threadedly carried by the lead screw 7, is displaced from the position indicated by the imaginary lines to the position indicated by the solid lines in FIG. 4. Then, as shown in FIG. 10, the free ends of the takeup shafts 20 move toward each other leaving a gap S therebetween and, as shown in FIGS. 14 through 17, the operation for clamping the lower end portion of the hanging knitted fabric W between the abutting member 27 of one takeup shaft 20 and the elastic member 19 of the other takeup shaft 20 is carried out.
More specifically, when the output shaft 41a of the actuator 41 is extended, the first and second levers 30 and 31, which are drivingly connected to the output shaft 41a, are caused to rotate about the pins 32 and 33, respectively, to the positions shown in FIG. 15 so that the third lever 34 together with a portion Wa of the knitted fabric W is inserted between the abutting member 27 and the elastic member 29 and the portion Wa is frictionally clamped between the members 27 and 29 by the clamping operation of the takeup shafts 20 as best shown in FIG. 17.
The output shaft 41a of the actuator 41 is then extracted to rotate the first and second levers 30 and 31 about the pins 32 and 33, respectively, in the counterclockwise direction so that the third lever 34 is returned to its initial or home position. In this case, as best shown in FIG. 18, the fabric thrust arm 39 is permitted to rotate only when the third lever 34 is returned to its initial position so that even when the fabric thrust arm 39 is brought into contact with the takeup shaft 20, it will not interfere with the return of the third lever 34 to its initial position.
Thereafter, both of the sliders 12, which are threadedly mounted on the lead screws 7, respectively, are displaced inwardly so that both of the takeup shafts 20 are further moved inwardly through the engaging arms 13 on the sliders 12, and consequently the portion Wa of the knitted fabric W is firmly clamped between the abutting member 27 of one takeup shaft 20 and the elastic member of the other takeup shaft 20. And under the condition as shown in FIG. 9, the actuators 26 are deenergized to withdraw their output shafts 26a so that the lock members 23 are caused to move downwardly under the stored forces of the coiled springs 24 and then the edges of the small-diameter holes 25a of the engaging holes 25 of the lock members 23 engage with the takeup shafts 20, respectively, whereby the takeup shafts 20 are securely held and prevented from moving outwardly. Thus, the takeup shafts 20 can be securely held in position and prevented from moving outwardly.
As a knitted fabric W is produced, the takeup shafts 20 are rotated intermittently as is well known to those skilled in the art by a ratchet drive mechanism (not shown) so that the knitted fabric W is gradually wound around the takeup shafts 20 in the form of a roll.
When the knitted fabric W has been rolled up to a full size in the manner described above, the roll thus produced is removed from the takeup shafts 20. To this end the actuators 26 are energized to extend their output shafts 26a as shown in FIG. 6 so that the engaging holes 25 of the lock members 23 are disengaged from the takeup shafts 20 against the force of the coiled springs 24. Then, the takeup shafts 20 are permitted to move outwardly in the axial direction. More specifically, when the actuators 26 are energized, the lock members 23 are caused to move upwardly so that the engaging holes 25 are disengaged from the peripheral grooves 20b (FIG. 7), respectively, of the takeup shafts 20 whereby the shafts are unlocked. Thereafter, the lead screws 7 are reversed in rotation so that the sliders 12, which are threadedly mounted on the lead screws 7, are moved outwardly away from each other. Then the engaging arms 13 of the sliders 12 cause the takeup shafts 20 to outwardly move away from each other so that the roll of knitted fabric W can be released from the takeup shafts 20.
The knitted fabric winding device described above is advantageous in that it is simple in construction so that the operation as well as the inspection and maintenance can be much facilitated. In addition, the rolled knitted fabric W can be reliably pulled from the takeup shafts, and labor saving as well as improvement of the rolled knitted fabric W can be attained without wasting time and labor because an efficient mass production can be carried out. Furthermore, when the knitted fabric is rolled, it is prevented from being contaminated and damaged by the hands of an operator so that the quality of the knitted fabric can be improved.
After the knitted fabric W has been rolled up to a desired size or diameter, the knitted fabric W which has been rolled cannot be taken out unless it is cut from the fabric that follows it. Cutting the fabric is performed by a cutting device. The following is a description of the cutting device.
As shown in FIG. 2, a feed screw 50 is horizontally supported by a pair of bearings 49 which are mounted on a bottom base 1a fixedly secured to the legs described above. The feed screw 50 extends so as to be perpendicular with respect to the takeup shaft 20 described above. To an end portion of the feed screw 50 a motor 51 such as a stepper motor, is linked via a coupling 52. On the base 1a below the feed screw 50 is provided a guide rail 53 parallel to the feed screw 50. As shown in FIGS. 2 and 22, a slider 54 that also acts as a guide is screwed to the feed screw 50, and the leg portions 54a of this slider 54 engage with a guide rail 53 so as to be freely movable. On this slider 54 is provided a lifter device 55 which is movable vertically to receive a roll of the knitted fabric W.
As best shown in FIG. 23, along the full length of the side wall of the upper portion of one of the stand frames 4 is horizontally fixed a guide rail 56 having an angle shape in cross section, and the horizontal web portion of this guide rail 56 supports thereon a lower rack unit 57 that also has an angle shape in cross section and is freely slidable. In addition, this lower rack unit 57 supports thereon an upper rack unit 58 that also has an angle shape in cross section. The upper side unit 58 is also slidable so as not to separate from the lower rack unit 57. To the top surface at about the center of the guide rail 56 is provided a protruding stopper 56a, and to the top surface at about the center of the lower rack unit 57 in the vicinity of the stopper 56a is provided a stop finger 59 which is pivoted by a pin 59b and engages with the stopper 56a. The stop finger 59 is formed so that a protrusion 59a extends in the upward direction. Furthermore, to the lower rack unit 57 in the vicinity of the stop finger 59 is fixedly provided an abutment member 57b which has an angle shape so as to slidably hold the vertical web of the upper rack unit 58. To a tail end portion (the right end portion as seen in FIG. 23) of the upper rack unit 58 is fixed a releasing member 58b that has an angle shape. A stop pin 60 protrudes transversely so that it can contact the abutment member 57b.
As shown in FIG. 23, to the side wall of the upper portion of the stand frame 4 is mounted a drive motor 61 such as a stepper motor for example, and the output shaft of this drive motor 61 supports a pinion 62 which engages the rack 58a of the upper rack unit 58 and then engages the rack 57a of the lower rack unit 57, as described later. As shown in FIG. 20, the width of the pinion 62 in the direction of the shaft is a width that can engage both racks 58a, 57a. The rack 57a terminates in the vicinity of the pinion 62, as shown in FIG. 23. To the forward portion of the upper rack unit 58 is pivotably supported a support lever 63 so as to be swingable about a pin 64. A pulling arm 65 is pivoted by a pin 66 on the support lever 63 in the vicinity of the pin 64. The pulling arm 65 is urged by a coiled spring 67 so that the arm 65 comes into contact with an inner side surface 4a of the stand frame. As shown in FIG. 22, when the knitted fabric W is to be cut, the upper rack unit 58 advances to the left as shown by the chain line in the figure, and the pulling arm 65 is urged by the coil spring 67 so that the support lever 63 rotates in the clockwise direction as viewed in FIG. 21 so as to take an orientation along the vertical web portion of the upper rack unit 58, whereby the support lever 63 is brought in line with the length of the upper rack unit 58. As shown in FIGS. 20, 21 and 22, to the free distal end portion of the support lever 63 is mounted a cutter unit 68.
As shown in FIG. 24, to a bracket 63a fixed to the free distal end portion of the support lever 63 is supported a pair of opposing fabric guide plates 69 and 70, and to the distal end opening portions of these fabric guide plates are formed fabric guide portions 69a and 70a that are cutout portions in the shape of a V, and that can guide the roll of the knitted fabric W. Between cutter 71 so as to be freely rotatable and so as to protrude into the fabric guide cutouts 69a and 70a. The disc cutter 71 is attached to an output shaft 71a of a motor 72 mounted on the bracket 63a. Furthermore, to the outer side of the fabric guide plate 70 is mounted a miscutting detection sensor 73 that has a detector 73a. The miscutting detection sensor 73 stops the operation of the motor 72 when it detects a miscut of the knitted fabric W. As shown in FIG. 21, when the cutter is not being used (that is, when it is stored), the cutter unit 68 is retracted into a recess of the leg 1 so that it does not interfere with other portions of the apparatus.
The following is a description of the operation of the cutting device.
When the knitted fabric W has been wound or rolled to a desired size on the takeup shaft 20, the lifter device 55 operates and raises the knitted fabric receiving platform and supports the roll of the knitted fabric W. Then, as has already been described, when each of the takeup shafts 20 is pulled outwards, the operation of the cutter unit 68 starts.
In FIGS. 22 and 23, first, when the drive motor 61 is operated, the pinion 62 of the drive motor 61 rotates whereby the upper rack unit 58 that engages with the pinion 62, moves toward the knitted fabric W. As a result, the pulling arm 65 is urged by the coil spring 67 so that arm comes into contact with the end surface of the guide rail 56. Because of this, as shown in FIG. 22, at the start of cutting of the knitted fabric W the upper rack unit 58 advances, and the pulling arm 65 is urged by the tensile force of the coil spring 67 so as to abut against the vertical web portion of the upper rack unit 58. When this occurs, the upper rack unit 58 continues to advance with the support lever 63 held in alignment with the length of the upper rack unit 58, and the rotating disc cutter 71 of the cutter unit 68 on the support lever 63 cuts across half of the width of the knitted fabric W.
In FIG. 23, the advancing of the upper rack unit 58 causes the releasing member 58b to press the protrusion 59a of the stop finger 59 and cancels the engagement with the stopper 56a. Simultaneously with this, the stop pin 60 of the upper rack unit 58 contacts the abutment members 57b of the lower rack unit 57. By this, the lower rack unit 57 begins to advance via the abutment member 57b and because of this, the pinion 62 engages with the rack 57a of the lower rack unit 57 so that the lower rack unit 57 also advances further toward the knitted fabric W, and the disc cutter 71 of the cutter unit 68 cuts the remaining half of the width of the knitted fabric W. After cutting, the reverse rotation of the pinion 62 reverses the motion of the lower rack unit 57 and the upper rack unit 58 so that they in effect fold over, and so that the cutter unit 68 is retracted into, and stored in the recess of the leg 1, where it does not interfere with the operation of other portions of the apparatus when it is not being used.
By the use of the cutting device as described above, it is possible to use a single disc cutter to cut the full width of the fabric and it is also possible to fold over the support mechanism of the disc cutter unit so that the cutter unit can be stored when it is not being used.
The following is a detailed description of the lifter device 55 that supports the roll of the knitted fabric W, as shown in FIG. 2.
In FIG. 26, the end portion of the slider 54 that is in screw engagement with the feed screw 50, horizontally supports a support frame 116 that has a square shape, and two sides of this support frame 116 each form a pair of guide plates 116a and 116b. Also, to each of the guide plates 116a, are horizontally screwed a lifting screw shaft 117 so as to extend perpendicular to the feed screw 50, and to a distal end portion of this screw shaft 117 is fixed a pulley 118. Furthermore, this pulley 118 is linked via a drive transmission belt 120 to a motor 119 such as a stepper motor. This motor 119 is supported by a bracket 116c on the support frame 116. A slider 121 is threaded to the screw shaft 117 and is horizontally provided with a pair of pressing rods 121a that are perpendicular with respect to the screw shaft 117, and to each of the distal end portions of these pressing rods 121a is pivoted the lower ends of each of the lifting struts 122. Also, the distal end portion of each of the guide plates 116b in the vicinity of the pressing rods 121a has a support pin 124 that pivots the lower end portion of another lifting strut 123. The lifting struts 122 and 123 intersect midway and the point of intersection is pivoted by means of a pin 125. Furthermore, on each of the upper distal ends of the lifting struts 122 and 123 is supported a fabric receiving platform 126, and as shown in FIG. 28, a receiving plate 127 of a substantially U-shape in cross section is mounted via a shock absorbing spring 128 and a support pin 129 to the fabric receiving platforms 126. Also, on the receiving plate 127 are provided a number of rollers 127a that are supported in parallel. Below the central portion of this receiving plate 127 is provided a knitted fabric detection sensor 130a such as a proximity switch that detects a full roll of the knitted fabric W when the roll is placed on the receiving plate 127. This knitted fabric detection sensor 130a operates to control the motor 119.
As shown in FIG. 26, in the running path of the slider 121 are provided detection switches S 1 and S 2 and these switches S 1 and S 2 detect the topmost position and the bottommost position of the lifting struts 122 and 123 of the lifter device 55, and each of these switches S 1 and S 2 controls the motor 119.
A fabric detection switch 130b is provided on the receiving plate 127, and when the knitted fabric W on the receiving plate 127 that has been moved away from the machine is removed, this switch 130b controls the operation of the motor 51 so that the receiving plate 127 returns to the initial position. The fabric detection switch 130b can be modified so that it can also be used as the fabric detection sensor 130a.
The following is a description of the lifter device 55.
The motor 119 starts operation when the knitted fabric W has formed a full roll on the takeup shaft 20 in the state shown in FIG. 26. When this occurs, the motor 119 rotates the pulley 118 via the transmission belt 120 whereby the lifting screw shaft 117 moves the slider 121 threaded to it. Accordingly, the pressing rods 121a of this slider 121 rotate the lifting struts 122 and 123 about their centers of their pin 125 so that they become more upright, and the fabric receiving platform 126 and the receiving plate 127 are lifted to the upper limit as shown in FIG. 29. The operation of the motor 119 stops when the knitted fabric detection sensor 130b detects abutment with the roll of the knitted fabric W.
Then, the takeup shafts 20 are pulled outward from the machine in the manner already described. As a result, as shown in FIG. 29, the roll of the knitted fabric W is placed gently on the receiving plate 127 on the fabric receiving platform 126. When this occurs, the knitted fabric detection sensor 130a operates, and the motor 119 rotates in reverse so that the motor 119 rotates the pulley 118 in reverse direction via the transmission belt 120 whereby the lifting screw shaft 117 moves the slider 121 back to its original position. Then, the pressing rods 121a of the slider 121 move back with each of the lifting struts 122 so that the receiving plate 127 and the fabric receiving platform 126 that is supported by the lifting struts 122 and 123 are lowered to, and stopped at the lowest position as shown in FIG. 30.
The lifter device 55 moves up and down within a range of raising and lowering operation determined by the switches S 1 and S 2 that are acted upon by the slider 121.
When the fabric receiving platform 126 has been lowered to, and stopped at the lowest position, the switch S 2 is operated so that the motor 51 operates. Because of this, the feed screw 50 that is coupled to the motor 51 rotates, and the lifter device 55 carrying the roll of knitted fabric W thereon together with the slider 54 is transported outward as shown in FIG. 31. Then, as shown in FIG. 32, the transportation stops after the position of the cutter unit 68 has been passed. When this occurs, the cutter unit 68 moves reciprocatingly as has been described, and after the knitted fabric W is cut, the roll of knitted fabric W is conveyed away from the machine to the next process, as shown by W' in FIG. 2.
FIG. 33 is a view of a modification. In this modification, a hydraulic or pneumatic cylinder device 132 is used instead of the pantograph mechanism of the lifter device 55 described above, and the fabric receiving platform 126 and the receiving plate 127 are mounted on the cylinder device 132 so that the configuration is simpler and inspection and maintenance are easier than the specific example described above.
The lifter device 55 described above was a specific example provided on the distal end portion of the slider 54, but it is also possible to have a design modification wherein a pair of lifter devices 55 are provided in a line to the front and rear of the slider 54 for example, so that each lifter device 55 operates alternately to receive each of the full rolls of knitted fabric W.
FIG. 34 through FIG. 41 are views showing a further modification where there are provided first and second lifter devices 55A and 55B having the same configuration as the lifter device 55 shown in FIG. 26. The configurations of the first and a second lifter devices 55A and 55B are the same so that those portions which correspond are indicated with corresponding reference numerals, and the corresponding descriptions of them are omitted. In this further modification, the first and a second lifter devices 55A and 55B are supported on a common slider 54, and a nut member 107 fixed to the bottom surface of this slider 54 is threaded to the feed screw 50 shown in FIGS. 35 and 36.
The following is a description of the operation of this further modification.
The operation of the first lifter device 55A starts as shown in FIG. 35 when the knitted fabric W has formed a full roll on the takeup shaft 20.
More specifically, in FIG. 34, the motor 119 of the first lifter device 55A operates whereby the motor 119 rotates the pulley 118 via the transmission belt 120 so that the lifting screw shaft 117 fixed to the pulley 118 moves the slider 121. As a result, the pressing rods 121a of this slider 121 press the lifting struts 122 and rotate them so that the lifting struts 122 and the other lifting struts 123 stand up around the center of the pin 125. Therefore, the receiving plate 127A and the first fabric receiving platform 126A that is mounted on the upper portion of the lifting struts 122 and 123 are raised to their upper limit positions, and a fabric detection switch 130b detects contact with the roll of the knitted fabric W and the operation of the motor 119 is stopped.
Then, when the takeup shafts 20 are pulled back toward the outside of the machine in the same manner as in the previous embodiment, the roll of knitted fabric W is gently placed on the receiving plate 127A. When this is done, the motor 119 operates in reverse, and via the transmission belt 120, this motor rotates the pulley 118 in reverse, so that the lifting screw shaft 117 of this pulley moves the slider 121 back to the original position. Then, the pressing rods 121a of this slider 121 move back together with the lifting struts 122 whereby the lifting struts 122 and 123 rotate around the center of the pin 125 and the receiving plate 127A and the first fabric receiving platform 126A are lowered to the bottommost position and stop there.
When the first fabric receiving platform 126A is lowered to, and stopped at the bottommost position, the switch S 2 operates the motor 51, and the feed screw 50 coupled to this motor 51 rotates. Consequently, as shown in FIG. 36, the first lifter device 55A on which is placed the first full roll of knitted fabric W, and the slider 54 that is threaded to the feed screw 50 move toward the outside while the second lifter device 55B moves to the initial position of the first lifter device 55A and stops there.
When the first full roll of knitted fabric W passes the above-described position for the cutter, the cutter unit moves reciprocatingly as described above, and cuts the trailing end portion of the knitted fabric W.
Then, the second lifter device 55B operates when the takeup shafts 20 have a second full roll of the knitted fabric W as shown in FIG. 36. More specifically, when the second full roll of the knitted fabric W is to be taken out, the second lifter device 55B is raised and comes into contact with the second full roll of knitted fabric W, and .after the second full roll of knitted fabric W has been transferred to the second fabric receiving plate 127B, the takeup shafts 20 are pulled outward and the second lifter device 55B lowers. After this, the feed screw 50 rotates and the slider 54 is moved to the outside. Then, when the second full roll of knitted fabric W passes the position of the cutter device, the trailing end portion of the second full roll of knitted fabric W is cut by the cutter device. After this, the second full roll of fabric is conveyed to the outside of the machine.
For the external diameter of the roll of knitted fabric W to reach approximately 40 cm it takes about 2.5 hours so that removing the full roll is performed about three times per day. Conveying the full roll to outside the machine can be performed together by placing the full rolls of knitted fabric W on the first lifter device 55A and the second lifter device 55B so that this conveying can involve a labor saving.
Another modification as shown in FIGS. 38 through 40 omits the pantograph mechanism of the first lifter device 55A, and a single cantilevered support 135 fixedly secured to the second lifter device 55B is extended horizontally to mount the first lifter device 55A thereon. The operation of this modification is as follows. When the first fabric receiving platform 126A and the receiving plate 127A are raised and lowered, the pantograph mechanism for the second lifter device 55B is used. Furthermore, also when the second fabric receiving platform 126B and the receiving plate 127B are raised and lowered, the same pantograph mechanism is used. Therefore, there is a simplification of the pantograph mechanism. Inspection and maintenance are therefore simplified when compared to the embodiment described above.
Finally, instead of the pantograph mechanism of the first lifter device 55A and the second lifter device 55B described above; another embodiment shown in FIG. 41 is provided with a first cylinder device 136A and a second cylinder device 136B that are either pneumatic or hydraulic cylinders. These cylinders are provided vertically to each of the sliders 54. To each of the output shafts of the first cylinder device 136A and second cylinder device 136B are respectively mounted a first fabric receiving platform 126A and a receiving plate 127A, and a second fabric receiving platform 126B and a receiving plate 127B. They operate in the same manner as described above.
In the previous embodiments, the first lifter device 55A and the second lifter device 55B are mounted on the upper portion of one of the slider 54, but the slider 54 can be divided into two and independently provided Furthermore, the first lifter device 55A and the second lifter device 55B may be respectively provided on each of these sliders 54, and the first lifter device and the second lifter device may raise and lower alternately so that each roll of knitted fabric W is received and taken out when it is full. | An apparatus for winding into a roll a knitted fabric produced in a circular knitting machine and for conveying the roll to the outside of the knitting machine. A knitted fabric hangs below the knitting machine and is wound around a pair of horizontally aligned takeup shafts that are shiftable away from each other and toward each other until they are thrust against each other. At the start of the winding operation, the takeup shafts are shifted toward each other, and when the shafts approach positions to leave a gap between inner gripping ends of these shafts, a knitted fabric insertion link mechanism provided alongside the takeup shafts is extended toward the gap, and a fabric thrust arm on a distal end of the link mechanism pushes and insert a portion of the lower starting end of the hanging fabric into the gap. Thereafter the gap is closed so that the lower starting end of the fabric is firmly gripped between the gripping ends to enable start of the winding operation. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This is a Continuation of U.S. application Ser. No. 11/686,102, filed on Mar. 14, 2007, allowed on Jun. 12, 2012 and issued as U.S. Pat. No. 8,287,336 B2, which was a Divisional of U.S. application Ser. No. 10/981,021, filed on Nov. 4, 2004, and issued as a U.S. Pat. No. 7,214,874 B2 on May 8, 2007, the subject matters of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a venting device for tamper resistant electronic modules, and more specifically to a venting device for electronic communications encryption modules that comply with Federal information Processing Standards 140-2 (FIPS 140-2), Level 4, security requirements.
2. Background Information
Federal Information Processing Standards 140-2 (FIPS 140-2) is a standard that describes U.S. federal government requirements that IT products should meet for Sensitive, but Unclassified (SBU) use. The Standard was published by the National Institute of Standards and Technology (NIST) in May 2001, and succeeds FIPS 140-1 published by NIST in January 1994. It has been adopted by the Canadian government's Communication Security Establishment (CSE), and is likely to be adopted by the financial community through the American National Standards Institute (ANSI). This technology has become of particular interest in the wake of growing threats to security both at home and abroad.
The standard defines security requirements that must be satisfied by a cryptographic module used in a security system protecting unclassified information within IT systems. There are four levels of security: from Level 1 (lowest) to Level 4 (highest). These levels are intended to cover the wide range of potential applications and environments in which cryptographic modules may be deployed.
Security level 4 provides the highest level of security defined in the standard. At this security level, the physical security mechanisms provide a complete envelope of protection around the cryptographic module with the intent of detecting and responding to all unauthorized attempts at physical access. Penetration of the cryptographic module enclosure from any direction has a very high probability of being detected, resulting in the immediate nullification of all critical security parameters stored in the module. Security level 4 cryptographic modules are useful for operation in physically unprotected environments.
The principal features of a typical electronic communications encryption module designed to meet the requirements of FIPS 140-2, Level 4, are illustrated in the cross-sectional view of FIG. 1 . At the heart of the encryption module is a circuit card 3 on which are mounted a number of integrated circuit chips (not shown) that provide the functionality of the encryption module. The circuit card 3 is enclosed in a copper inner case 2 . Rivets 4 align the circuit card 3 and hold the cover of the inner case in place. The inner case 2 is wrapped in a tamper sensing resistive mesh 5 . To assure complete coverage, the edges of the tamper sensing mesh 5 are overlapped on a portion 7 of the inner case 2 . The inner case 2 wrapped in the mesh 5 is encapsulated with polyurethane 6 , and the encapsulated assembly placed in a copper outer case 1 . The complete enclosure is airtight.
FIG. 2 shows further details of the outside of inner case 2 . Windows 12 are openings provided for flex cables connecting the circuit card 3 to a PCI printed circuit assembly or similar interface. Windows 22 are openings through which the tamper sensing mesh 5 will be connected to the circuit card 3 .
FIG. 3 a shows the encryption module at the stage where flex cables 31 are connected to the circuit board 3 , and the mesh 5 is in the process of being wrapped around the inner case 2 . As noted above, flex cables 31 connect the circuit card 3 to a PCI printed circuit assembly or similar interface through windows 12 . Mesh cables connect the tamper sensing resistive mesh 5 to the circuit card 3 through windows 22 . This connection is illustrated in further detail in FIG. 3 b . Through this connection, the circuit board 3 can sense when an attempt is made to gain access to the communications encryption module. If the tamper sensing resistive mesh 5 is damaged, the hardware on the circuit card 3 is programmed to nullify all of the encryption technology within the module.
The hermetically sealed assembly illustrated in FIGS. 1-3 has exhibited failure when exposed to reliability testing conditions that include temperature cycling, and when used in high temperature applications. FIGS. 4 a - e show the sequence of events leading to mesh damage and failure. As temperature increases in FIG. 4 a over room temperature, pressure of the trapped air 8 on the enclosing mesh 5 increases in accordance with the ideal gas law. This causes the mesh to tent in the vicinity of the window 22 through which the mesh enters the inner case 2 , as shown in FIG. 4 b . Air pressure and polyurethane expansion in the confined space, as shown in FIG. 4 c , cause deformation of the copper outer case 1 . Case deformation allows delamination between the primary layer and the overlap layer of the mesh 5 , as shown in FIG. 4 d . The mesh 5 can fail at this point or when, as shown in FIG. 4 e , the case deformation is large enough that the mesh-to-mesh delamination reaches the mesh-to-polyurethane interface.
The use of a vent to relieve internal air pressure in the communications encryption module has been considered, but the concern is that even a small vent would allow access inside the enclosure and therefore violate FIPS 140-2, Level 4 requirements. Moreover it is believed that the manufacture of a tamper sensing resistive mesh allowing for such a vent would fail independent testing for FIPS compliance due the breach in protection of the package.
SUMMARY OF THE INVENTION
It is, therefore, a principle object of this invention to provide a venting device for tamper resistant electronic modules.
It is another object of the invention to provide a venting device for tamper resistant electronic modules that solves the above-mentioned problems.
These and other objects of the present invention are accomplished by the venting device for tamper resistant electronic modules that is disclosed herein.
In an exemplary aspect of the invention, a tamper resistant enclosure for an electronic circuit, designed to meet FIPS 140-2, Level 4, security requirements, includes an inner case for enclosing the electronic circuit, a tamper sensing mesh wrapped around the inner case in such a manner that edges of the tamper sensing mesh form overlapping layers on a portion of the inner case, an outer case enclosing the inner case and the tamper sensing mesh, and a venting device forming a vent channel from inside the inner case to outside the outer case, the vent channel passing between the overlapping layers of the tamper sensing mesh and having at least one right angle bend along its length. The inner case and the outer case are metallic and preferably made of copper. Further, an encapsulant, preferably made of a urethane material, fills the space between the inner case and the outer case.
In another aspect of the invention, the venting device is comprised of two strips of a thin material laminated together along their length, and a length of yarn sandwiched between the two thin strips and extending from one end of the strips to the other end of the strips to form a vent channel. In a preferred embodiment, the strips are composed of a polyamide coverlay material, and the yarn is a wool yarn. The venting device may also include a third strip of thin material interposed between the first and second thin strips, the third strip having one or more holes along its length through which the length of yarn is laced as it proceeds from one end of the venting device to the other. In an alternative embodiment, the length of yarn follows a zig-zag path between the first and second strips. Preferably, the zig-zag path includes at least one right angle bend.
In a further aspect of the invention, a method of manufacturing the subject venting device includes the steps of placing in a laminating press a sandwich comprising two strips of coverlay material each with a layer of thermally activated adhesive, and a length of wool yarn interposed between the two thin strips and extending from one end of the strips to the other end of the strips to form a vent channel, and laminating the two strips together with the yarn in between at elevated temperature and pressure for a predetermined period of time. For the preferred embodiment, the laminating process is performed at a temperature of approximately 300° F. and a pressure of approximately 75 PSI for a period of approximately 45 minutes. The method may further include layering sponge rubber on both sides of the sandwich before the laminating step, and employing in the laminating press platens having grooves that defines the vent channel. To manufacture the embodiment of the invention in which the vent channel follows a zig-zag path, the method preferably includes the steps of forming matching holes in the two strips of coverlay material and inserting pins through the matching holes to guide the length of yarn interposed between the two strips in a zig-zag path between one end of the strips and the other end of the strips.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified cross-sectional view of a typical electronic communications encryption module designed to meet the requirements of FIPS 140-2, Level 4.
FIG. 2 is a perspective view showing details of the outside of the inner case of the encryption module of FIG. 1 .
FIG. 3 a is a perspective view showing the inner case of the encryption module being wrapped in a tamper sensing resistive mesh.
FIG. 3 b is a simplified cross-sectional view showing the connection of the tamper sensing resistive mesh to the circuit card located within the inner case of the encryption module.
FIGS. 4 a - 4 e are a series of simplified cross-sectional views illustrating a failure mechanism of the tamper sensing resistive mesh at elevated temperatures due to air trapped within the inner case of the encryption module.
FIG. 5 is a cross-sectional view of an electronic communication encryption module illustrating the placement of a venting device according to the present invention.
FIG. 6 shows a first embodiment of a venting device for an electronic communication encryption module according to the present invention.
FIG. 7 shows a second embodiment of a venting device for an electronic communication encryption module according to the present invention.
FIG. 8 shows a third embodiment of a venting device for an electronic communication encryption module according to the present invention.
FIG. 9 shows a fourth embodiment of a venting device for an electronic communication encryption module according to the present invention.
FIG. 10 is a chart showing internal temperature and pressure versus time of sealed encryption modules with differing degrees of venting.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention will now be described in more detail by way of example with reference to the embodiments shown in the accompanying figures. It should be kept in mind that the following described embodiments are only presented by way of example and should not be construed as limiting the inventive concept to any particular physical configuration.
Further, if used and unless otherwise stated, the terms “upper,” “lower,” “front,” “back,” “over,” “under,” and similar such terms are not to be construed as limiting the invention to a particular orientation. Instead, these terms are used only on a relative basis.
The present invention is directed to a venting device suitable for tamper resistant electronic module that must meet FIPS 140-2 standards for communications encryption equipment. As discussed above, the tamper resistant encryption module typically consists of a circuit card with several integrated circuit devices and is mounted inside an inner metallic case with openings for flexcables. The flexcables are used to connect the card to a PCI printed circuit assembly or other suitable interface. To make the card tamperproof, an electronic shield in the form of a resistive mesh is wrapped around the inner can. The inner can is enclosed in an outer metallic can with the required polyurethane encapsulant filling the space between them. The whole assembly is heated to 80° C. using a specific temperature profile in order for the polyurethane to cure. During this manufacturing operation air gets entrapped in the inner case and has no way to escape. During operation of the card, the pressure developed by the trapped air is high enough to cause shear delamination and failure of the electronic shield over the flexcable opening in the inner case.
FIG. 5 shows by way of example how a venting device can be added to the communications encryption module of FIG. 1 in a manner compliant with the FIPS 140-2, Level 4, standard. The venting device 10 passes through an opening in the inner case 2 where there are overlapping layers 5 a , 5 b of the tamper sensing mesh 5 . The venting device 10 passes between the inner layer 5 a , which is in contact with the inner case 2 , and the outer layer 5 b , which is wrapped over the venting device. In the example shown, there is a 90° bend in the venting device as it exits the inner case, in order to comply with a FIPS 140-2, Level 4, requirement that a standard vent tube have at least one 90° bend between the interior of the package and the exterior.
FIGS. 6 a - b show side and top views of a first embodiment of a venting device that employs no moving parts. In this embodiment, the vent consists of a channel formed between two strips 61 , 62 of a thin material that are laminated together along their length. The vent channel itself is defined by a length of yarn 63 sandwiched between the thin strips 61 , 62 .
In this embodiment, the thin strips are made of a coverlay material, which is typically a polyimide or polyester material commonly used as a film applied to flexible printed circuits to protect and insulate the copper wiring. Other materials having similar properties can be substituted.
The yarn acts as a gas-permeable “semisolid” to prevent access to the inside of the module while allowing the passage of air so as to equalize the pressure in the interior of the inner case to the pressure on the exterior of the outer case. In this embodiment, the yarn consists of two lengths of four-ply wool yarn twisted together. Other types of yarn, such as glass yarn, can be substituted.
To make the venting device shown in this embodiment, the two strips of coverlay material, each 0.001 inch thick and each with a 0.001 inch layer of thermally activated adhesive, are laminated together in a standard flex circuit laminating press at approximately 300° F. and 70 PSI for a period of approximately 45 minutes. The yarn adheres to the coverlay due to the thermally activated adhesive. Sponge rubber or similar material is laid on both sides of the coverlay sandwich during the laminating process so as not to crush the yarn that forms the vent channel. To aid in the definition of the vent, the platens of the press could be made with a channel for the yarn.
As shown in FIG. 5 , the venting device according to the first embodiment is inserted through an opening in the inner case 2 , and passes between the overlapping layers of tamper sensing mesh 5 and through the polyurethane 6 between the inner and outer cases. A pressure sensitive adhesive is used to adhere the venting device to the first layer of mesh. In use, it is observed that a pressure differential of between 0 and 0.1 atmospheres must exist between the inside of the inner case and the outside of the outer case before air begins to flow between through the venting device. This threshold effect is attributed to the pressure that the cured urethane foam exerts on the sides of venting device.
A second embodiment of the venting device is illustrated in the side and top views of FIGS. 7 a - b . In this alternate embodiment, another layer 71 of thin material, e.g., a 0.001-inch thick polyimide layer, is placed in the middle of the coverlay/yarn sandwich. A hole 72 is drilled in the polyimide layer and the yarn passes through the hole, passing from one side of the polyimide to the other side. By passing from one side of the polyimide the other side, two 90° of bends are formed in the vent channel. This satisfies the FIPS 140-2, Level 4, requirement for at least one 90° bend between the interior of the package and the exterior.
A third embodiment is shown in the side and top views of FIGS. 8 a - b , where a third layer 81 of thin material is also used. However, in this case, two holes 82 , 83 are drilled in the third layer side-by-side, and the yarn is first through one hole and then back through the other, to emerge on the same side. In this manner, six 90° bends are formed. Further alternative versions of the third embodiment are possible using different patterns of holes in the third layer of coverlay material.
Moreover, it is possible to form the yarn vent channel in a zigzag pattern with any number of 90° bends, without using the third layer as a pattern. FIGS. 9 a - 9 c illustrate side, top and transverse views, respectively, of a fourth embodiment in which small holes 91 , 92 are formed in the coverlay strips 93 , 94 and pins (not shown) inserted in the holes to act as guides that cause the yarn material to change direction. Once the venting device is formed the pins are removed and the holes covered, such as with a thin acrylate label material (not shown), to prevent air from leaking out.
In the venting device of the foregoing embodiments, the coverlay adhesive not only holds the package together hut also serves to hold the yarn in place so that it cannot be pushed out of the way. Because of the many layers of fiber within the yarn, the adhesive also serves to keep the yarn together as a unit. The coverlay itself is fragile and any attempts to follow the vent channel through the yarn will damage the coverlay. When the coverlay is damaged, it gives direct access to damage of the tamper sensitive resistive mesh. If the tamper sensitive resistive mesh is damaged, the circuitry inside the package is programmed to nullify all the encryption technology within the module. Fragile tamper circuitry can be added to the coverlay itself around the vent channel and this can also be monitored by the module to detect any attempts to gain access to the encryption technology. As another alternative, the vent can be made an integral part of the flex cables 31 shown in FIG. 3 .
As can be seen in FIG. 5 , the venting device has a primary 90° bend in the mesh. FIGS. 7-9 show how further 90° bends can be added as desired to make access into the package more difficult. These extra 90° bends should be made between the layers of mesh for the most optimum function. By being between the layers of mesh, they increase the level of tamper resistance and tamper detection by the module. If required, multiple vents can be added to the module, or multiple channels can be made in one venting device.
Because of the air resistance of the vent channel, the venting process will take a period of time. The optimum venting time is either much less than or somewhat more than one-quarter the period of the thermal cycle to which the module is exposed. As shown in FIG. 10 , the worst case occurs when the venting time is equal to one-quarter of the cycling time. This creates higher peak pressures at high temperatures and lower low pressures at low temperatures. Accordingly, the vent time needs to be optimized to avoid this condition.
Some embodiments of the present invention may further include a check valve or the like, either in the vent channel or in a separate duct. The check valve in these embodiments should both actuate at a relatively low pressure (e.g., around 0.01 atm) and be sufficiently limited in valve travel so as to prevent introduction, either intentional or accidental, of foreign materials. These embodiments may be desirable where a high flow rate through the vent channel is required.
It should be understood that the invention is not necessarily limited to the specific process, arrangement, materials and components shown and described above, but may be susceptible to numerous variations within the scope of the invention. For example, although the above-described exemplary aspects of the invention are believed to be particularly well suited for tamper resistant communications encryption modules, it is contemplated that the concepts of the present invention can be utilized whenever it is desired to vent any tamper resistant electronic assembly.
It will be apparent to one skilled in the art that the manner of making and using the claimed invention has been adequately disclosed in the above-written description of the preferred embodiments taken together with the drawings.
It will be understood that the above description of the preferred embodiments of the present invention are susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | A tamper resistant enclosure for an electronic circuit includes an inner copper case, a tamper sensing mesh wrapped around the inner case, an outer copper case enclosing the inner case and the tamper sensing mesh, and a venting device forming a vent channel from inside the inner case to outside the outer case, the vent channel passing between overlapping layers of the tamper sensing mesh and having at least one right angle bend along its length. The venting device consists of two strips of a thin polyamide coverlay material laminated together along their length, and a length of wool yarn sandwiched between the two thin strips and extending from one end of the strips to the other end of the strips to form the vent channel. The length of yarn follows a zig-zag path between the first and second strips, the zig-zag path including at least one right angle bend. | 8 |
FIELD OF THE INVENTION
The present invention relates to a method for continuous production of carbon fibers and a vertical carbonizing apparatus for conducting the method. More particularly, the invention relates to a method using a vertical carbonizing furnace through which a fiber stock is guided downwardly and which is provided in the carbonizing chamber with at least one inert gas injection hole for forming a curtain of inert gas, as well as another hole made in the vicinity of said injection hole through which to draw a gas out of the carbonizing chamber, and to an apparatus for producing carbon fibers in such a manner.
BACKGROUND OF THE INVENTION
The production of carbon fibers generally consists of preoxidizing organic fibers (e.g. polyacrylonitrile fibers or cellulose fibers) in an oxidizing atmosphere to render them flame-retardant, and feeding the preoxidized fibers into a carbonizing furnace where they are carbonized in an inert gas atmosphere or a non-oxidizing atmosphere at a temperature of 300° C. or higher. In this carbonizing step, the preoxidized organic fibers are thermally decomposed into carbon fibers. The carbonization is usually effected at a temperature between 300° and 1,500° C., sometimes higher than 1,500° C., and if necessary, at the graphitization temperature of 2,000° C. or more (see U.S. Pat. Nos. 4,073,870 and 4,321,446).
The carbon fibers produced by the above described conventional method has very low strength and ductility due not only to internal defects from microvoids but also to surface defects such as cracks. Therefore, to produce carbon fibers of high performance, the presence of surface defects must be minimized. In the carbonizing step, the preoxidized fibers release various decomposition products as they are carbonized at increasing temperatures, and the release of most decomposition products is known to occur in a temperature range of 300° to 900° C. The decomposition products formed in this temperature range, for example, HCN, NH 3 , CO, H 2 , H 2 O, CH 4 , CO 2 and higher molecular weight saturated and unsaturated hydrocarbons having 3 to 7 carbon atoms are gaseous under the temperature conditions where they are produced. However, in a vertical carbonizing furnace where preoxidized fibers are guided down through a heating chamber in which the temperature increases from the top to bottom, the gaseous decomposition products (hereunder decomposition gases) are carried by the ascending gas stream into the low-temperature zone of the furnace where the higher molecular weight hydrocarbons are cooled to form a tar mist. Part of the decomposition products now in the form of a tar mist is deposited on the inner surface of the furnace wall or the fiber surfaces. The sticky tar mist on the wall surfaces catches fiber fuzz adrift in the furnace and grows during continuous furnace operation. Ultimately it contacts and damages the surface of the fiber passing through the furnace or partially obstructs the passage of the fibers to upset the uniform flow of the gas stream. If the contact between the fibers and the tar mist is extreme, the individual filaments stick to each other, and the buildup of tar mist at elevated temperatures causes surface defects that greatly reduce the strength and ductility of the carbon fiber product. Furthermore, decomposition gases such as H 2 O, CO 2 and CO lower the fiber strength appreciably when they contact the fibers in the high-temperature zone of the furnace.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method for continuous production of carbon fibers having high performance.
Another object of the present invention is to provide an apparatus capable of continuous production of carbon fibers having high performance.
The present invention has been accomplished as a result of studies to develop an effective method and apparatus of removing decomposition gases (that have been produced at between about 300° and 900° C.) from a vertical carbonizing furnace of the type described above wherein preoxidized filaments are fed from above and are carbonized as they are guided substantially vertically through the furnace.
The object of the present invention can be attained by a method which comprises using a vertical carbonizing furance having a heating chamber, heating the chamber in such a manner that the temperature gradually increases from the upper end toward a lower end of the heating chamber, introducing a fiber to be carbonized from a fiber inlet provided at the upper end of the chamber, introducing an inert gas from the gas inlet provided at lower end of the chamber to maintain the atmosphere in the chamber non-oxidizing atmosphere, injecting an inert gas from at least one portion between the fiber inlet and the gas inlet to form a curtain of the inert gas across the heating chamber to prevent decomposition gases formed in the heating chamber to ascend, discharging the decomposition gases with the inert gas from at least one gas outlet each being provided at a lower portion of each inert gas injection portion, and recovering carbonized fiber from a fiber outlet provided at the lower portion of the heating chamber.
The method of the present invention can be carried out by using an apparatus which comprises:
A vertical carbonizing furnace having a heating chamber therein for carbonizing fibers, the furnace including,
(i) a fiber inlet at the upper end of the chamber,
(ii) an air tight sealed fiber outlet at the lower end of the furnace,
(iii) an inert gas inlet provided on the wall of the chamber and above the fiber outlet,
(iv) at least one inert gas injection portion, formed on the wall of the chamber, each capable of forming a curtain of inert gas across the heating chamber, each injection portion being provided between the gas inlet and the fiber inlet,
(v) at least one gas outlet each being provided at a lower portion of each inert gas injection portion, and
(vi) a heating member capable of controlling the temperature in the heating chamber in such a manner that the temperature gradually increases from the upper end toward a lower end of the heating chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross section of one embodiment of the apparatus of the present invention;
FIG. 2 is an enlarged schematic view showing the inert gas injection portions, gas outlets and the nearby area of an apparatus according to another embodiment of the present invention; and
FIG. 3 is a schematic cross section of an apparatus according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
When preoxidized fibers are carbonized by the method of the present invention or carbonized in the apparatus of the present invention, the flowing of the decomposition gases produced in the higher-temperature zone into the lower-temperature zone can be prevented or reduced, thereby tar mist deposition on the inner wall surface or fiber surfaces can also be prevented or reduced. Furthermore, it is also possible to prevent or reduce the decomposition gases from contacting the surface of the fibers being carbonized. Thus, carbon fibers of consistently good quality can be produced over an extended period. The apparatus of the present invention is effectively used for carbonizing preoxidized fibers in a temperature range of about 300° to 900° C. where the formation of thermal decomposition gases is particularly noticeable.
Illustrative fibers that can be effectively treated by the method or by the apparatus of the present invention include preoxidized fibers obtained from acrylic or cellulose fibers that generate thermal decomposition gases when they are subjected to the ordinary carbonization step. These fibers are fed to the heating chamber usually in the form of a strand or two made up of about 100 to 500,000 filaments, or in a fabric or nonwoven cloth form. Any number of strands or tows may be guided through a single heating furnace at the same time. When fibers are supplied as strands, the apparatus of the present invention is able to increase the strand spacing to about twice as large as that permissible with an apparatus having neither inert gas injecting portion nor gas outlet provided below the gas injection portion.
The method and the apparatus of the present invention is hereunder described in greater detail by reference to the accompanying drawings. FIG. 1 is a schematic cross section of one embodiment of the apparatus. In this figure, fibers 1 to be treated are introduced into a heating chamber 2 for carbonizing the fibers. The inner space of the heating chamber 2 serves both as a carbonizing chamber and as the passage way for the fibers. The upper end of the heating chamber is provided with a fiber inlet 3 and is open to air. The lower end of the heating chamber is provided with a fiber outlet 7 which communicates with a sealing mechanism (not shown). The heating chamber 2 is surrounded by heating elements 4a, 4b and 4c.
At the upper end of the heating chamber, an ascending gas stream establishes a seal to prevent the entrance of the atmosphere into the chamber. It is preferred to provide a gas outlet 5 below the fiber inlet 3 at the upper portion of the chamber. The function of this gas outlet 5 is to maintain an inert gas atmosphere in the interior of the heating chamber 2 by displacing external gases (e.g. air and water vapor that have entered the chamber through the fiber inlet together with the fibers) with the ascending flow of the gas that has been introduced into the chamber from below. When the ascending flow of gas introduced into the furnace from below is drawn out of the system through the fiber inlet 3, the gas in the furnace is quenched at the inlet 3 and its nearby area, whereupon the decomposition gases in the furnace gas form a tar mist which builds up on the surface of the fibers or the fiber inlet to cause various defects such as the breakage of the fibers or the adhesion between filmanets. This can be effectively prevented by disposing the gas outlet 5 between the fiber inlet 3 and the first heating element 4a positioned below it. The gas outlet 5 is provided at such a position (i.e. distance from the fiber inlet 3) that the above-stated two objects are achieved: (1) the greatest portion of the decomposition gases in the heating chamber is drawn out of the system through the outlet 5, and (2) the air in the bundle of fibers introduced into the heating chamber is substantially completely replaced by an inert gas by the time the fibers have travelled from the fiber inlet 3 and the gas outlet 5. If necessary, the fiber inlet 3 may be heated to prevent the buildup of tar mist in that area.
The lower end of the heating chamber is provided with a fiber outlet 7 which communicates with a sealing mechanism (not shown). Above the fiber outlet 7 is positioned an inert gas inlet 6. An inert gas is usually supplied in the rate from 0.02-0.50 Nm/sec (calculated to the rate at the normal state). Preoxidized fiber is supplied to the heating chamber having the construction described above, where it is carbonized in the inner space (carbonizing chamber) and subsequently recovered through the sealing mechanism at the lower end. The sealing mechanism may be in any suitable form such as a liquid seal, roller seal or an inert gas curtain seal. The fibers coming out of the carbonizing chamber are either wound on a take-up roll or continuously supplied to another furnace held at higher temperatures. The heating elements 4a, 4b and 4c are so designed that the temperature within the heating chamber increases gradually in the travelling direction of the fibers. The stream of inert gas (which was not drawn out of the chamber) flows in the heating chamber in the direction opposite the travelling direction of the fibers.
In this embodiment of the apparatus of the present invention, inert gas injecting portions 8a and 8b are provided between the inert gas inlet 6 at the bottom of the heating chamber and the gas outlet 5 at the upper portion. Each of the inert gas injecting portions may be composed of a single hole (usually in the form of a horizontally elongated slit) or it may comprise a plurality of slit-like openings arranged side by side horizontally as shown in FIG. 2. The inert gas injecting portion may be formed on only one of the two opposing faces of the heating chamber wall, or it may be formed on both walls as shown in FIGS. 1 and 2. More effective removal of decomposition gases and the displacement of the furnace gas with an inert gas may be accomplished by disposing another injecting portion 8c above and in close proximity with the gas outlet 5 as shown in FIG. 1. FIG. 2 is an enlarged schematic view of inert gas injecting portions 8 and 8', gas outlets 10 and 10', and the nearby area.
Suitable inert gases are, for example, nitrogen, argon, helium and mixtures thereof.
The inert gas is injected through 8a and 8b after having heated by preheating elements 9a and 9b (and 9c if injecting portion 8c is also provided) to the temperature in the furnace or a higher temperature but not higher than the temperature in the furnace by more than 200° C. The inert gas injected into the heating chamber through the inert gas injecting portions traverses the heating chamber to form a curtain of inert gas around each fiber thus providing a shield from the gas stream coming up from the lower part of the heating chamber. The ascending internal gas obstructed by the curtain of inert gas is drawn from the system through gas outlets 10a and 10b (and 5 when 8c is provided). The interior of the heating chamber is usually held at a pressure of approximately 2 to 100 mmH 2 O, so by connecting the gas outlets 10a, 10b and 5 to pressure regulating valves 11a, 11b and 11c, the pressure within the heating chamber can be held constant as the gas is ejected from these outlets. Accordingly, no air will be drawn into the chamber through the fiber inlet 3. Like the inert gas injecting portion(s), the gas outlet(s) may be provided in one of the opposing faces of the chamber wall (as in FIG. 1) or in both walls (as in FIG. 2). In the former case, the outlet(s) may be formed below and in close proximity with the inert gas injecting portion or they may be formed in an area of the chamber wall which is the opposite side to the wall where the injection holes are formed and which is below and in close proximity with the injection holes. The gas outlets are preferably provided at a position as close as possible to the injection holes. If the fibers to be carbonized are in the form having a very great density (strand spacing in the case of strand) in the heating chamber, the hole arrangement shown in FIG. 2 is suitable, and if the density is small, any arrangement may be used.
Referring to FIG. 2, the inert gas injected through the injecting portions 8, 8' toward the fibers 1 forms a gaseous curtain around each fiber to obstruct the flow of the ascending gas, which is drawn out of the furnace through, outlets 10 and 10'. At least one layer (usually more than one layer) of inert gas injecting portion is formed within the heating chamber, and a number of gaseous curtains equal to number of layer of the injecting portions are formed. One layer of injecting portion is usually formed between each of heating elements 4a, 4b and 4c in the furnace, and at least two layers of injecting portions preferably formed. The purpose of the present invention is satisfactorily achieved by not more than five layers of injecting portions.
Usually, fibers arranged into one vertical plane are supplied to the chamber. When fibers are supplied to the chamber as strands the strand spacing (number of strands per meter of width of the fiber plane) is usually from 50 to 400 strands/m (provided strands of 1,000-50,000 filaments/strand are used) and when fibers are supplied as tows they are usually spread to 2,000,000 to 10,000,000 denier/m. When fibers are supplied as fabric or non-woven cloth of not more than 500 g/m 2 can be effectively treated in the apparatus of the present invention. The fibers travel through the heating chamber under a tension which is at least sufficient to prevent them from contacting the wall of the chamber. The tension generally ranges from 1 to 600 mg/d, preferably from 50 to 300 mg/d. The travelling speed of the fibers depends on the length of the heating chamber and the temperature within that chamber. The speed usually ranges from 0.02 to 0.20 m/sec. The inert gas is injected at a flow rate sufficient to permit the ascending gas to be drawn out of the furnace through the gas outlets so that the concentration of the decomposition products in the ascending gas is preferably reduced to less than about 50%. For this purpose, when the inert gas is injected from the both sides of wallss of the chamber wherein strands are arranged side by side, the flow rate of the inert gas in the direction vertical to the fiber surface generally ranges from 0.3 to 3 Nm/sec, preferably from 0.5 to 1.5 Nm/sec. The inert gas is preferably injected in such a direction that a horizontal gaseous curtain is formed within the heating chamber; therefore, it is directed into the heating chamber either horizontally or slightly downwardly. Part of the inert gas introduced is drawn out of the furnace together with the decomposition gases and the remainder ascends the furnace. In the apparatus of the present invention, the fibers are carbonized by being heated in a temperature which is gradually raised from about 300° C. to a temperature of not more than about 950° C., usually, about 900° C.
When the apparatus of the present invention is used to produce carbon fibers, the decomposition gases formed within the heating chamber can be discharged from the furnace with reduced chance of contacting the fibers being carbonized or the gas in the upper part of the furnace which is in the lower temperature zone. As a result, the amount of the decomposition gases that build up on the surface of the fibers or the wall of the furnace as a tar mist is reduced to such an extent that carbon fibers of good quality can be consistently produced over an extended period.
One embodiment of the present invention where carbon fibers are produced from acrylonitrile fibers with the apparatus of FIG. 1 is hereunder described. A strand or tow of preoxidized acrylonitrile fibers having a bonded oxygen content of 6-15 wt%, preferably 8 to 12 wt% is fed to the furnace through inlet 3, which is preferably preheated to 250°-350° C. to prevent tar deposition. The fibers pass through the upper part of the heating chamber that is being heated usually at approximately a temperature having an incline of from 300° to 500° C. by heating element 4a, and by the time when they reach the gas outlet 5, the gas, particularly air, contained in the bundle of fibers is replaced by the internal gas that has been present in the heating chamber, and is then discharged from the system through outlet 5. The replacement of the confined air by the internal gas must be thorough for the fibers which are usually supplied in the form of the bundle comprising 100 to 500,000 filaments. The fibers then pass through a zone where a curtain of an inert gas such as nitrogen, argon or helium is formed. Thereafter, they enter a second hot zone which is usually heated to have an incline of a temperature from about 500° to 700° C. by heating element 4b. The inert gas is preheated to the temperature of the zone below the gas inlet or a higher temperature that does not exceed that temperature by more than 200° C. The purpose of this preheating is to prevent the decomposition gases from being quenched by the introduced inert gas to form a mist and for minimizing the fluctuation of the temperature in the furnace. The inert gas should be blown against the fibers gently to prevent the formation of fiber fuzz or fluffs.
In the second hot zone, the fibers are subjected to a heat treatment at about 500°-700° C. for a period of about 10 to 60 seconds. Thereafter, they are passed through another curtain of inert gas, then to a third hot zone which is usually heated to a temperature having an incline of from about 750° to a temperature of 900° C. or more than 900° C. but not more than 950° C. by heating element 4c. The fibers are retained in this zone for about 5 to 40 seconds. The temperatures provided by heating elements 4a, 4b and 4c vary stepwise but the temperature within the heating tube gradually increases from top to bottom. Finally, the fibers are recovered from the system through fiber outlet 7 and a sealing mechanism. A preferred sealing mechanism is the combination of a curtain of nitrogen gas and a roller seal. The recovered fibers that have been carbonized to a small extent (so called pre-carbonized) are then fed to a furnace which is held at a higher temperature of about 900° to 1,500° C. in an inert gas atmosphere, and by holding them in that furnace for a period of about 35 to 200 seconds, carbon fibers having the following properties are obtained.
______________________________________Fineness: 790-810 texTensile modulus of elasticity 23,900-25,000 kg/mm.sup.2Ultimate tensile strength 415-450 kg/mm.sup.2, co- efficient of variation (CV) = 4% or lessElongation at failure 1.72-1.86%______________________________________
The apparatus of the present invention can be operated continuously, for example, for 480 hours, with 300 bundles of 12,000 preoxidized filaments being fed simultaneously. The resulting carbon fibers have high quality in that they have few fluffs and cohering filmanets and have uniform strength properties. As another advantage, decomposition gases formed in the apparatus can be recovered in high concentration, so the emission gas from the apparatus can be easily disposed in an incinerator.
When the same apparatus was operated continuously for about 320 hours without injecting an inert gas into the heating chamber and without drawing the internal gas from the furnace through several outlets, the furnace was partly obstructed by the fiber fluffs and tar mist deposited on the wall of the zone heated at temperatures between 300° and 700° C. The resulting product was fluffy, had a tensile strength of less than 350 kg/mm 2 (CV=9% or more) and was not uniform in its strength.
FIG. 3 shows an apparatus of another embodiment of the present invention. This apparatus is the same as that shown in FIG. 1 except that the apparatus of FIG. 3 has an additional heating chamber 12 which is provided downwardly in contact with the heating chamber 2. In the heating chamber 12 further carbonization of the fiber is conducted. In the heating chamber 12 the temperature is kept at a higher temperature than that of the heating chamber 2. The fibers which have been heated in the heating chamber 2 to a temperature up to 900°-950° C. are continuously path through the heating chamber 12. In the heating chamber 12 the fibers are heated in an inert gas atmosphere and at a temperature having a incline of from a temperature higher than the temperature of the heating chamber 2 to a temperature of not more than 1500° C. The thus carbonized fibers are recovered from the outlet 7.
EXAMPLE 1
A strand (comprising 12,000 filaments) of fibers prepared from a copolymer consisting of 98% by weight of acrylonitrile and 2% by weight of methylacrylate, and having an individual fineness of 0.9 denier was preoxidized in the air at 265° C. for 0.38 hour, at 275° C. for 0.20 hour and at 283° C. for 0.15 hour under a tension so that shrinkage of the fiber reached 50% of the free shrinkage at that temperature. The thus obtained preoxidized fibers had bonded-oxygen of 9.8% by weight.
The tow of preoxidized fibers was carbonized using the apparatus shown in FIG. 1. The strand was fed to the furnace through inlet 3, which was preheated to 350° C. The strand spacing was 140 strands/m. The temperature of the upper zone was heated to have an incline of a temperature of from 300° to 500° C. by the heating element 4a, in the same manner the middle zone was heated to 500°-700° C. by the heating element 4b and the lower zone was heated to 700°-900° C. by the heating element 4c. Nitrogen gas was used as the inert gas. The gas which introduced from the gas inlet 6 was heated to 600° C., the gases which were injected from 8c, 8a and 8b were heated to 400° C., 600° C. and 750° C., respectively. The flow rate of the gas in the chamber 2 was 0.15 Nm/sec. Flow rates at fiber surfaces at 8c, 8a and 8b were 1.00 Nm/sec, 0.75 Nm/sec and 0.50 Nm/sec., respectively. The carbonization of the fiber was conducted under a tension of 80 mg/d. The speed of the fiber was 0.11 m/sec and the residence time was 66 sec.
The interior pressure of the heating chamber was maintained at 3-7 mmH 2 O and decomposition gases were discharged from gas outlets 10a, 10b and 5. The recovered fibers that have been carbonized (pre-carbonized) were than fed to a furnace which was heated to a temperature having an incline of from 900° to 1420° C. and which was kept under N 2 gas atmosphere, and the fibers were held in that furnace for 60 seconds.
For comparison the same experiment was conducted except that the inert gas was not injected from 8a, 8b and 8c and the decomposition gas was not discharged from 10a and 10b.
The thus obtained carbon fibers had the following properties as shown in the following table.
______________________________________ The Present Invention Comparison______________________________________Tensile Strength 450 kg/mm.sup.2 350 kg/mm.sup.2(kg/mm.sup.2)Tensile Modulus of 24.0 × 10.sup.3 kg/mm.sup.2 24.0 × 10.sup.3Elasticity (kg/mm.sup.2) kg/mm.sup.2Elongation at Failure 1.88 1.46Continuous Stable more than about 200 hoursManufacturing Period 480 hours(Period during whichcontinuous manufacturingcarbon fibers can beconducted without causingfuzzy strands or breakageof fibers)______________________________________
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | A method for producing carbon fibers in a vertical carbonizing furnace and an apparatus for producing carbon fibers using such a method are disclosed. The furnace includes a heating chamber for carbonizing fibers, the furnace including,
(i) a fiber inlet at the upper end of the chamber
(ii) an air tight sealed fiber outlet at the lower end of the furnace,
(iii) an inert gas inlet provided on the wall of the chamber and above the fiber outlet,
(iv) at least one inert gas injection portion, formed on the wall of the chamber, each capable of forming a curtain of inert gas across the heating chamber, each injection portion being provided between the gas inlet and the fiber inlet,
(v) at least one outlet each being provided below each inert gas injection portion, and
(vi) a heating member capable of controlling the temperature in the heating chamber in such a manner that the temperature gradually increases from the upper end toward a lower end of the heating chamber. The carbon fibers produced by this method or apparatus are excellent in that they have few fluffs and cohering filaments and improved strength and ductility. | 3 |
[0001] The present application claims priority to Chinese Patent Application No. 201310440458.4, filed on Sep. 24, 2013.
BACKGROUND OF THE INVENTION
[0002] Cabazitaxel belongs to the taxane class and is closely related in both chemical structure and mode of action to the anticancer drugs paclitaxel and docetaxel. Cabazitaxel, chemically known as (2α, 5β7β, 10β, 13α)-4-acetoxy-13({2,3S)-3-[(tert-butoxycarbonyl)amino]-2-hydroxy -3 -phenylpropanoyl}oxy)-1-hydroxy-7,10-dimethoxy-9-oxo-5,20-epoxy-tax -11-en-2-yl benzoate, is represented by formula (I).
[0000]
[0003] Cabazitaxel is microtuble inhibitor, which can promote the formation of tubulin by combined with tubulin protein, while cabazitaxel also an prevent the mierotubule assembled to disassemble.
[0004] Crystalline form is one of the important factors to affect the drug quality, drug efficacy and performance of pharmaceutic preparation. In view of the good effect of cabazitaxel, the people have made a lot of research on it and developed many crystalline form. Finally, crystalline acetone solvate form of (2α, 5β, 7β, 10β, 13α)-4-acetoxy -13-({2,3 S)-3-[(tert-butoxycarbonyl)amino]-2-hydroxy-3phenylpropanoyl}oxy)-1-hydroxy-7,10-dimethoxy-9-oxo-5,20-epoxy-tax-11-en-2-yl benzoate is known and described in WO2005028462, which is named crystalline form A. Followed crystalline forms B, C, D, E, F are known and described in Chinese patent CN101918385, which are all converted from form A. While crystalline form B, D, E, F ethanol solvates are also known and described in patent CN101918385.
[0005] In summary, as we know, the preparation of crystalline forms of cabazitaxel needs specific environment to realize, which is had to industrialize. Further more, in the process of the preparation of crystalline form, we can find high temperature has been used to remove the solvent which makes the purity of the product to decrease. It is also known that the ability of a substance to exist in more than one crystal form is defined as polymorphism and its different crystal forms are called polymorphs. Polymorphs will affect the solubility, stability and bioavailability of drug, furthermore it will affect the quality, safety, effectiveness and application of drug.
BRIEF SUMMARY OF THE INVENTION
[0006] In one aspect, the present invention provides a crystalline form of cabazitaxel. The novel form have chemically characterized by 1 HNMR (nuclear magnetic resonance) spectroscopy, XRPD, FTIR (Fourier transform infrared) spectroscopy (also abbreviated to IR spectroscopy), TGA (theramgravimetric analysis) DSC (differential scanning calorimetry).
[0007] In second aspect, the present invention provides the method of preparations for the novel crystal line form.
[0008] In third aspect, the present invention provides process for the preparation of the crystalline form W of cabazitaxel. In some embodiments, the inventive process includes:
[0009] a) any kind of crystalline form of cabazitaxel dissolves in appropriate organic solvent, appropriate ionized water is added slowly, after finished dropwise the solution is kept at 20-25° C. for 16 hours, then colorless crystal formed;
[0010] b) filtering the solid and washed the solid with methanol (50%);
[0011] c) drying the isolated and washed solid resulting from step b) under vacuum, at 40-50° C.;
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows the XRPD pattern for cabazitaxel Form W.
[0013] FIG. 2 shows the DCS trace of cabazitaxel Form W.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The present invention provides novel crystalline form W of cabazitaxel. The crystalline forms can be produced by method described herein in substantially pure form, i.e., at least with 80% purity or higher. Form W can be produced with a purity of at least 90%, preferably at least 95% and more preferably at least 98% and the most preferably at least 99%.
[0015] In one aspect, the present invention provides a crystalline form of (2α, 5β, 7β, 10β, 13α)-4-acetoxy-13-({(2,3 S)-3-[(tert,butoxycarbonyl)amino]-2-hydroxy-3-phenylpropanoyl}oxy)-1-hydroxy-7, 10-dimethoxy-9-oxo-5,20-epoxy-tax-11-en-2-yl benzoate.
[0016] The crystalline compound of the present invention can be characterized by a number of techniques including X-ray power diffraction (XRPD), infrared spectroscopy (IR), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and crystallography.
[0017] In some embodiments, the present invention provides the crystalline form of the compound characterized by an XRPD pattern substantially in accordance with that of FIG. 1 .
[0018] In other embodiments, the crystalline form of the compound is Form W. characterized by XRPD pattern that includes one or more peaks at 4.4, 7.8, 8.5, 11.4, 12.8 15.3, 17.0, 20.4, 21.4, 22.5, 23.4, 27.8, 29.7, 29.9, 33.3 and 34.3 degrees 2θ (±0.2 degrees 2θ). Wherein said XRPD patter is made using CuKα 1 radiation. Preferably, the XRPD pattern shall have at least the following peaks 4.4, 8.5, 17.0 and 21.4 degrees.
[0019] Crystalline Form W of the present invention is also characterized by a DSC substantially in accordance with FIG. 2 .
[0020] In a related aspect, the present invention provides a process for preparing crystalline Form W of cabazitaxel including:
[0021] a.) any kind of crystalline form of cabazitaxel dissolves in appropriate organic solvent, appropriate ionized water is added slowly, after finished drop wise the solution is kept at 20-25° C. for 16 hours, then colorless crystal formed;
[0022] b) filtering the solid and washed the solid with methanol (50% aqueous);
[0023] c) drying the isolated and washed solid resulting from step b) under at 40-50° C.
[0024] The organic solvent above-mentioned include methanol, ethanol, isopropanol and acetonitrile etc. Appropriate ionized water is added slowly, while keep the volume radio of organic solvent and water at the range of 55:45-85:15. The temperature of the solution must be kept at 15-25° C. during the crystallizing. The drying time should be kept below 24 hours and the temperature should be kept at 40-50° C.
[0025] The present invention will be described more fully by means a the following examples which should not be considered to limit the invention.
[0000] Experimental analysis conditions:
Differential scanning calorimetry (DSC):
[0026] The measurements were carried out on a T.A. The sample is subjected to temperature programming from 30° C. to 300° C. with a heating rate of 5° C./min. The product was placed in a crimped aluminum capsule and the amount of product analyzed is between 2 and 5 mg.
Power X-ray Diffraction (PXRD)
[0027] The analyses were carried out on a Panalytical X'Pert Pro diffractometer with a reflection-mode Braff-Brentano focusing geometry (θ-2θ) assembly. The product analyzed is deposited as a thin layer on a silicon single crystal. A copper anticathode tube (45 kV/40 mA) supplies an incident radiation Cu-Kα 1 ) (λ=1.54056). The beam is collimated using Sollers slits which improve the parallelism and variable slits which limit scattering. An X'celerator detector completes the device. The diagram recording characteristics are the following: sweeping from 2 to 40 degree, 0.01°/1sec.
EXAMPLES
[0028] The following examples are provided to further illustrate, but not to limit this invention.
Example 1
[0029] Cabazitaxel (500 mg) was dissolved in 10 mL of methanol, and then ionized water (5 mL) was dropwised into it with stirring. Then the solution was kept at 15-25° C. for 16 hours. Then the mixture was filtered, and the collected solids were washed with methanol (50% aqueous) and dried in vacuum at 40° C. for 24 hours to give cabazitaxel Form W (490 mg, purity: 99.6%) as colorless solid (melting point 153.78 ° C).
Example 2
[0030] Cabazitaxel (500 mg) was dissolved in 10 mL of ethanol, and then ionized water (5 mL) was dropwised into it with stirring. Then the solution was kept at 15-25° C. for 16 hours. Then the mixture was filtered, and the collected solids were washed with ethanol (50% aqueous) and dried in vacuum at 40° C. for 24 hours to give cabazitaxel Form W (492 mg, purity: 99.2%) as colorless solid.
Example 3
[0031] Cabazitaxel (500 mg) was dissolved in 10 mL of IPA, and then ionized water (5 mL) was dropwised into it with stirring. Then the solution was kept at 15-25° C. for 16 hours. Then the mixture was filtered, and the collected solids were washed with IPA (50% aqueous) and dried in vacuum at 40° C. for 24 hours to give cabazitaxel Form W (460 mg, purity: 99.3%) as colorless solid.
Example 4
[0032] Cabazitaxel (500 mg) was dissolved in 10 mL of acetonitrile, and then ionized water (5 mL) was dropwised into it with stirring. Then the solution was kept at 15-25° C. for 16 hours. Then the mixture was filtered, and the collected solids were washed with acetonitrile (50% aqueous) and dried in vacuum at 40-50° C. for 24 hours to give cabazitaxel Form W (482 mg, purity: 98.9%) as colorless solid.
[0033] powder X-ray diffraction and DSC data on form W is summarized in the following Table 1 and compared with existing polymorphs:
[0000]
TABLE 1
Form
Patent
Characteristic peak
mp (° C.)
Anhydrous B
CN101918385A
7.3, 8.1, 9.8, 10.4, 11.1, 12.7, 13.1, 14.3, 15.4
150
Anhydrous C
CN101918385A
4.3, 6.8, 7.4, 8.7, 10.1, 11.1, 11.9, 12.3, 12.6,
146
13.1
Anhydrous D
CN101918385A
3.9, 7.7, 7.8, 7.9, 8.6, 9.7, 10.6, 10.8, 11.1,
175
12.3
Anhydrous E
CN101918385A
7.1, 8.1, 8.9, 10.2, 10.8, 12.5, 12.7, 13.2, 13.4,
157
13.9
Anhydrous F
CN101918385A
4.4, 7.2, 8.2, 8.3, 8.8, 9.6, 10.2, 10.9, 11.2, 12.1
148
12.3
Ethanol
CN101918385A
7.3, 7.8, 8.8, 10.2, 12.6, 12.9, 13.4, 14.2, 14.7,
N/A
solvate B
15.1
Ethanol
CN101918385A
3.8, 7.5, 7.7, 8.4, 9.4, 10.3, 10.5, 11.1, 11.5,
N/A
solvate D
11.9
Ethanol
CN101918385A
7.1, 8.1, 8.8, 10.2, 10.7, 12.5, 13.2, 13.4, 13.9,
N/A
solvate E
14.2
Ethanol water
CN101918385A
4.4, 7.2, 8.2, 8.3, 8.8, 9.6, 10.3, 10.9, 11.2,
N/A
F
12.2
Monohydrate
CN101918385A
4.3, 6.8, 7.4, 8.6, 10.1, 11.1, 11.9, 12.2, 12.6,
N/A
C
13.3
Dihydrate C
CN101918385A
4.2, 6.9, 7.5, 8.4, 9.9, 10.9, 11.7, 12.3, 12.6,
N/A
13.2
Anhydrous
CN102675257A
4.3, 7.1, 8.7, 10.2, 10.9, 12.2, 13.8, 15.2, 16.4,
N/A
solvate
17.0, 17.6, 18.3, 19.2, 19.6, 20.3
Ester solvate
CN102746258A
7.9, 8.5, 10.1, 12.6, 14.0, 15.0, 15.8, 17.3,
N/A
J
19.4, 20.1
Hydrate G
CN102746258A
4.5, 8.5, 8.9, 11.1, 12.4, 13.9, 15.4, 17.7, 19.3
N/A
Form 1
CN102746258A
7.4, 7.8, 8.9, 10.1, 14.4, 15.0, 15.7, 17.7, 19.6,
N/A
23.5
IPA solvate
WO2013069027
7.4, 7.9, 8.9, 10.3, 12.6, 13.3, 14.4, 15.2, 16.5,
156.98
A1
17.0, 17.7, 18.3, 19.5, 20.5
Form 1
WO2013080217
7.3, 8.1, 8.9, 9.8, 10.4, 11.1, 12.7, 14.3, 15.3,
134.01,
A2
15.8
159.58
Form 2
WO2013080217
3.9, 6.9, 7.8, 10.2, 10.7, 11.6, 12.2, 12.8, 13.6,
68.5,
A2
14.0, 15.1, 17.2, 18.1
114.9,
174
Form 3
WO2013080217
4.2, 6.9, 7.5, 8.5, 8.6, 10.1. 11.0, 11.8, 12.3,
71.59
A2
12.6, 13.3, 13.4, 13.8, 14.3, 35.1, 15.6
Form 4
WO2013080217
6.9, 7.9, 10.2, 10.7, 12.2, 13.9, 15.1, 17.2,
45.35,
A2
18.1, 19.8
124.92
Form 5
WO2013080217
7.5, 7.9, 8.6, 10.0, 12.6, 13.3, 14.1. 14.8, 15.0,
56.29,
A2
15.8, 16.7, 17.4, 18.0, 18.8, 19.4, 20.1
145.27
Form 6
WO2013080217
7.5, 7.9, 8.6, 9.0, 10.0, 12.5, 13.2, 13.8, 14.1,
157.26
A2
15.0, 15.5, 15.8, 16.6, 17.3, 17.8, 18.8, 19.6,
20.1
Form 7
WO2013080217
5.2, 6.0, 7.5, 8.9, 9.5, 10.1, 10.7, 11.7, 12.1,
162
A2
12.8, 13.3, 14.1, 15.3, 16.1, 17.1, 17.6, 18.1,
18.9, 19.6
Form 8
W02013080217
7.5, 7.9, 8.6, 10.0, 12.6, 13.3, 14.1, 14.8, 15.8,
151.84,
A2
16.7, 17.0, 17.5, 18.0, 18.9, 19.4
159.08
Form 9
WO2013080217
7.5, 7.9, 15.0, 15.8, 18.1, 19.4, 20.1, 22.6
156.51
A2
Form 10
WO2013080217
7.4, 7.7, 8.8, 10.1, 12.2, 12.7, 13.2, 14.4, 15.3,
163.24
A2
16.2, 16.9, 17.6, 18.0, 18.7, 19.4
Form 11
WO2013080217
7.4, 7.7, 8.8, 10.1, 12.2, 12.7, 13.2, 14.4, 14.8,
162.26
A2
15.3, 15.6, 16.2, 16.9, 17.6, 18.0, 18.4, 19.4
Form 12
WO2013080217
7.2, 7.7, 8.1, 8.9, 9.8, 10.3, 11.0, 12.6, 13.2,
150.47
A2
14.2, 14.8, 15.1, 15.7, 16.3, 17.1, 17.5, 18.5,
19.4, 19.8
Form 13
WO2013080217
7.6, 8.2, 8.9, 9.7, 10.2, 10.9, 11.7, 12.6, 13.1,
119.57
13.6, 14.5, 15.1, 15.8, 16.2, 17.0, 17.8, 18.3,
19.2, 19.9
Ethyl acetate
WO2013088335
7.5, 7.9, 8.7, 10.1, 10.2, 12.6, 12.9, 13.8,
N/A
solvate
A1
14.1, 14.8
Form W
Present invention
4.4, 7.8, 8.5, 11.4, 12.8, 15.3, 17.0, 20.4, 21.4
153.78
22.5, 23.4, 27.8, 29.7, 29.9, 33.3, 34.3 | The present invention relates to a novel crystalline polymorph form W of cabazitaxel and to method for the preparation thereof. | 2 |
This invention relates to a bank of sleeper moulds for the moulding of a concrete sleeper in an in-line moulding installation.
BACKGROUND OF THE INVENTION
In an in-line moulding installation, shoulders are positioned through apertures in the bases of the moulds so that the shoulder stems project upwardly and the portions of the shoulders, which will, in use, accept the rail retaining clips, depend from the moulds (the sleepers being moulded upside down), reinforcing wires are run along the length of the line of moulds and are tensioned, the concrete is poured to embody the upstanding shoulder stems, the concrete is allowed to at least partly cure and spacers between adjacent sets of moulds are withdrawn, and after sufficient additional curing has taken place, the reinforcing wires are severed between the sleepers of adjacent moulds. The moulds are then inverted, and the completed sleepers discharged onto a fork-lift truck or other handling means.
One difficulty which is encountered with certain types of shoulders is that they must be accurately located, and to this end the apertures in the mould bases must be a close enough fit for the shoulders that there is little movement. If the clearance space between the shoulder edges and the walls defining the apertures is too small, removal of the moulded sleepers from the moulds is rendered difficult, while if they are too large, there is a flow-through of slurry from the concrete mix and this will deposit upon locating means and retention means carried beneath the sleeper moulds, and if this occurs a great deal of time needs to be spent in maintenance and cleaning between pours of concrete in the installation.
This invention is particularly directed to use with a concrete sleeper shoulder of the type having a stem to be embodied within the concrete, and an upwardly directed recess defined by a front (datum) wall and side wings, and wherein the side wings contain wing side recesses which face one another. Such shoulders are known in the art and will accept plate-like clips.
BRIEF SUMMARY OF THE INVENTION
An object of this invention is to provide improvements whereby the build-up of slurry beneath moulds on locating bars or fingers is substantially reduced. Another object of this invention is to provide improvements which allow a more accurate positioning of the shoulder in the aperture provided in the mould. Briefly, according to this invention therefore, there are provided improvements in a bank of sleeper moulds wherein the moulds lie side by side and contain shoulder receiving apertures which locate shoulders during pouring, the improvements including a rocker shaft journalled for rotation with respect to the moulds and having retaining members thereon which retain the shoulders and urge them into engagement with locating means.
More specifically, in an embodiment of this invention, the improvements comprise a rocker shaft for rotation about its longitudinal axis, a plurality of retaining members carried on the rocker shaft, the shape, size and location of each said retaining member being such that it releasably retains a shoulder when engaged thereby, and locating means also located below the moulds and so positioned as to locate the shoulders with respect to the moulds when the retaining members urge the shoulders into engagement with the locating means.
One of the difficulties which is encountered in the moulding of concrete sleepers is that although steel and concrete normally have about the same coefficient of expansion, when the mould is heated for curing the concrete there is a temperature differential between the concrete and its steel mould and this results in relative movement between the steel moulds and the concrete sleepers. Such movement makes removal of shoulder locating means very difficult, but in this invention the locating means can comprise a withdrawable locating pin which can be withdrawn immediately after pouring, and before the concrete sets, simultaneously wiping any wet slurry from its outer surface and providing clearance for relative movement between the moulds and shoulders which are themselves embedded in the concrete.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention is described hereunder in some detail with reference to, and is illustrated in, the accompanying drawings, in which
FIG. 1 is a plan view of a bank of moulds in which five sleepers can be moulded side-by-side,
FIG. 2 is a side elevation of FIG. 1,
FIG. 3 is an end elevation of FIG. 2,
FIG. 4 is a fragmentary sectional side elevation drawn to a larger scale, illustrating two rocker shafts each with retaining members thereon for retaining shoulders against locating means beneath the moulds,
FIG. 5 is a sectional end elevation taken on line 5--5 of FIG. 4, and
FIG. 6 is a fragmentary perspective view which illustrates the retention and location of a shoulder.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In this embodiment an in-line sleeper installation is provided with a plurality of banks 10 of moulds 11 arranged end to end but spaced from one another by spacers, only one bank being shown. The moulds 11 are arranged in their banks 10 side by side across the bed between sides 12, and each mould is provided with four rectangular apertures 13 which receive portions of cast iron shoulders 14 (shown in chain dot), the shoulders extending through the apertures 13 to have upstanding stems 15 which become embedded in concrete as it is poured into the moulds.
In this embodiment use is made of a type of shoulder 14 which has a depending portion 16 below the mould which comprises a front (datum) wall 17 arranged (in use) to locate against the edge of a rail foot for the maintaining of gauge of a rail line, and this is flanked by two outwardly projecting side wings 18 spaced from one another which, together with the front datum wall, define an underside recess 19. Each of the side wings 18 itself contains a respective inwardly directed shallow plate retaining recess 20 which, in use, will accept portion of a plate type of rail retaining clip (not shown). Such shoulder/retaining clip combinations are well-known.
The aperture walls which define each respective rectangular aperture 13 for receiving the depending portion 16 of its shoulder 14 are only slightly larger than that shoulder portion 16 so that the required tolerance is maintained, and beneath but slightly to one side of each aperture there is located a long circular locating pin 25 with a handle 26 at one end, and this pin is fed into the space beneath the bank of moulds, through an aperture in a first guide block 27 on one side wall and projects out through an aperture in a second guide block 27 on the other side wall (FIGS. 2 and 5), and when so positioned its surface provides a location point P (FIG. 4) against which datum wall 27 of each of a plurality of shoulders 14 bear. There are also provided guide plates 28 on the outer surfaces of the mould sides intermediate the guide blocks 27, also containing pin apertures. All the pin apertures are designated 29.
There is also provided a rocker shaft 30 parallel to the withdrawable locating pin 25, the rocker shaft 30 having bosses 31 thereon which constrain it against axial movement and having a plurality of retaining members 32 thereon, in this embodiment each retaining member 32 being of spring steel rod formed to a loop shape, which is a `U` shape both in plan and in end elevation, the sides 33 of the loop entering the wing side recesses 20 and the bridge 34 bridging across them, one rocker shaft 30 being rotatable at one end by means of a transverse bar 36 pivoted on a projecting end of the rocker shaft 30 (FIG. 6). An adjacent rocker shaft 30 (for an adjacent shoulder), parallel to the first, is similarly rotatable, by a spanner, and in the reverse direction for retention purposes. Spanner engagement flats are provided on the boss 31 of the adjacent rocker shaft 30 for this purpose. Each rocker shaft 30 is journalled in the blocks 27. An end of each rocker shaft contains a slot 37, the pivoted end of bar 36 being in one slot and its swinging end being engageable in the other, but only when both rocker shafts 30 are rotated so that the slots are aligned, and that is when there is sufficient resilient deformation that the retaining members 32 on the rocker shafts 30 to urge all transversely aligned shoulders 14 in one direction so that the front datum walls 17 are placed into firm engagement with a surface on one or other of the relevant locating pins 25. A spring/ball detent 38 releasably retains bar 36 in this position. It should be noted that tolerance can be lost if the deformation is excessive.
After the concrete has been poured but before it has set, the withdrawable locating pins 25 are withdrawn through their apertures in guide blocks 27, and this performs a function of wiping off any wet slurry which may otherwise adhere to the locating pins. After the concrete has set, (or after it has cured), the rocker shafts 30 are rotated so as to release the retaining members 32 from their respective shoulder wing recesses 20. The locating pins are withdrawn before any heat is applied to the moulds, and there is almost no likelihood of "binding" of the shoulders in the moulds which carry them against any locating surface beneath the moulds. The amount of cleaning is reduced to almost nothing because of cleaning by the edges of the apertures of each guide block 27 which supports the withdrawable locating pins, whereby the pin surfaces are scraped clean. Even if slurry build up does take place, it is unlikely to build up on the locating surfaces which are the cleaned surfaces of the locating pins.
A consideration of the above embodiment will indicate that the invention provides means whereby the location of the shoulders can be effected in a fast operation, and there is a considerable saving for maintenance and cleaning with respect to other known mould locating means.
Various modifications in structure and/or function may be made to the disclosed embodiments by one skilled in the art without departing from the scope of the invention as defined by the claims. | In a bank of sleeper moulds wherein the moulds lie side by side and contain shoulder receiving apertures which locate shoulders during pouring, the improvements including a rocker shaft journalled for rotation with respect to the moulds and having retaining members thereon which retain the shoulders and urge them into engagement with locating means. | 1 |
This is a divisional of U.S. patent application Ser. No. 700,191, filed June 28, 1976.
BACKGROUND OF THE INVENTION
This invention relates to an improved magnetic record member for use in magnetic recording devices such as a magnetic disc and a magnetic drum and a process for manufacturing same.
A magnetic recording device basically consists of magnetic heads for recording and reproducing (referred to simply as "head" hereinafter) and magnetic record members.
In general, recording and reproducing systems for the magnetic recording device may be classified into two types. In one system, upon the initiation of operation, a head is brought into contact with the surface of a magnetic record member and then, the record member is rotated at a given speed in a manner to provide a spacing between the head and the magnetic record member surface, thereby enabling the recording and reproducing operations. According to this system, upon completion of operation, rotation of the record member is stopped in a state where the head and record member are maintained in frictional contact with each other as is the case with the starting of operation.
In another system, after a magnetic record member is rotated at a given speed beforehand, a head is suddenly urged against the record member surface to provide a spacing due to an air layer created between the head and the record member so as to perform the recording and reproducing operations. As a result, the latter system brings the head and record member into frictional contact with each other when the head is urged against the record member surface.
Such frictional contact tends to harm the head and the magnetic record member so that satisfactory recording and reproducing operations become impossible. In addition, there is a case where the head unexpectedly contacts the record member surface so that the head and record member may both be damaged. Also, even if the head and record members are not damaged, a load is increasingly imposed on a spring for supporting the head as the contacting frequency of the head and record member is increased. For this reason, the spacing between the head and the recording surface of the member is varied. Besides these, a magnetic metal thin film medium used as the record member is possibly subjected to a high temperature and high humidity environment so that the record member surfaces experiences corrosion. This affects the magnetic characteristics of the member, and as a result, deteriorates the recording and reproducing characteristics thereof. Consequently, this requires the provision of a protective film or an over-layer on the surface of the magnetic metal thin film medium serving as one magnetic memory medium of the magnetic recording device.
The following characteristics must be required for the aforesaid protective film.
(1) A protective film medium should withstand an unexpected or inadvertent contact of a head with a magnetic record member during recording and reproducing operations (Resistance to head-crushing).
(2) The load imposed on a spring should be small, which is caused by a frictional force for supporting the head exerted by frictional contact of the head with the record member at a plurality of contacting cycles (lubricity).
(3) Even due to such frictional contacts at a plurality of contacting cycles, the protective film medium should be maintained in a state which is free of damage and peeling (Anti-abrasion characteristic).
(4) Even at high temperature and high humidity conditions, the protective film medium should protect the magnetic metal thin film medium so as to insure desired recording and reproducing characteristics (Resistance to environmental conditions).
(5) The protective film medium should not impair the magnetic characteristics of a metal substrate including the magnetic memory medium. U.S. Pat. No. 3,466,156 teaches the use of a polymer film and a wax lubricant film as a protective film formed by coating polyamide resins and ceresin wax. However, the use of this protective film has several disadvantages. In other words, the polymer film and the wax lubricant (film) are easily flaked off by frictional contact of a head against a magnetic record member at a plurality of contacting cycles. In this manner, this protective film fails to meet the characteristics (2) and (3).
Moreover, it is known that SiO 2 is coated using a spattering process on a magnetic record member as a protective film. However, the film formed by spattering SiO 2 fails to meet the characteristics (1) and (2). Also, a successful attempt to meet the characteristics (1) to (5) is known in the technique for coating glass through a spattering process as a protective film. However, the use of the spattering process unavoidably brings about the difficulty in the manufacture on a mass-production basis, and hence, the cost increase in the manufacture. Also, there is another disadvantage in that the size increase in the magnetic record member is accompanied with that of the target for spattering. For this reason, technical difficulty is encountered, with an unavoidable increase in the total cost of the apparatus.
It is an object of the present invention to provide a magnetic record member and a process for manufacturing the same free of the aforesaid shortcomings in the prior art magnetic record members.
BRIEF DESCRIPTION OF THE INVENTION
The present magnetic record member comprises an alloy disc, a non-magnetic alloy layer coated on the alloy disc and polished to a mirror surface, a magnetic metal thin film medium coated on the polished non-magnetic alloy layer and a polysilicate film coated on the magnetic metal thin film medium.
The present manufacturing process for the magnetic record member comprises the steps of: forming a film of a non-magnetic alloy on the surface of an alloy disc; polishing the non-magnetic alloy layer thus formed to a mirror surface; forming a magnetic metal thin film medium on the surface of the highly polished non-magnetic alloy layer; applying a solution of tetrahydroxy silane derived by hydrolysis of tetraalkoxy silane onto said thin film medium; baking the disc after having thus prepared the composite layers at a temperature of more than one hundred degrees centigrade in such a manner that variation in the magnetic property of the thin film medium will not adversely effect the recording and reproducing characteristics of the magnetic record member whereby a polysilicate film is formed on the thin film medium.
Also, the present magnetic record member comprises a mirror-polished alloy disc, a magnetic metal thin film medium coated directly on the alloy disc and a polysilicate film medium coated on the magnetic metal thin film is thus provided.
The present manufacturing process for the last described magnetic record member comprises the steps of: forming a magnetic metal thin film medium directly on the surface of the alloy disc polished to a mirror surface; applying a solution of tetrahydroxy silane derived by hydrolysis of tetraalcoxy silane onto said thin film medium; baking the disc after having thus prepared the layer at a temperature greater than one hundred degrees centigrade in such a manner that the variation in the magnetic property of the thin film medium will not give adverse effects on the recording and reproducing characteristics of the magnetic record member whereby a polysilicate film is formed on the thin film medium.
BRIEF DESCRIPTION OF THE FIGURE
The objects and other features of the present invention will be described more in detail in conjunction with the accompanying FIGURE which shows an end view of one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In the drawing, a magnetic record member 5 of the present invention comprises an alloy disc 1, a non-magnetic alloy layer 2 coated on the surface of the alloy disc 1, a magnetic metal thin film medium 3 coated on the highly-polished surface or mirror surface of the non-magnetic alloy layer 2 and a protective film 4 made of polysilicate and formed on the thin film medium 3.
The present record member 5 is manufactured by the steps of: plating a non-magnetic alloy on the surface of the alloy disc 1; forming a magnetic metal thin film medium on the polished surface of the thus formed alloy layer 2 by a plating process; applying a solution of tetrahydroxy silane derived by hydrolysis of tetraalkoxy silane on the surface of the thin film medium 3; baking the disc after having thus prepared the composite layers at a temperature greater than 100° C. (one hundred degrees centigrade) in a manner that variation in the magnetic property of the thin film medium 3 will not adversely affect the recording and reproducing characteristics of the magnetic record member; and thereby forming the polysilicate film 4, which is a polymer of tetrahydroxy silane, on the surface of the thin film medium 3.
The alloy disc 1 must be finished to a slightly topographic surface (no more than 50 μm (fifty microns) in the circumferential direction and no more than 10 μm (ten microns) in the radial direction of the disc.
This is because an increase in topograph leads to a failure of a head to satisfactorily float or fly above the magnetic record member surface upon recording or reproducing with the result of variation in spacing of the head from the record member. This varies the recording and reproducing characteristics of the record member, either in cases where the head makes contact with the record member surface or in cases where the head is spaced from the member surface.
The surface of the non-magnetic alloy layer 2 plated on the surface of the alloy disc 1 is highly polished to a surface roughness less than 0.04 μm by mechanical polishing. It is to be noted that if a metal which may be polished to a mirror surface is used as the alloy disc 1, the alloy layer 2 is unnecessary. The thin film medium 3 adaptable for high-density recording is placed on the surface of the alloy layer 2. The protective film 4 made of polysilicate protects the medium 3 from experiencing any frictional contact and chemical attack caused by prevailing temperature and humidity. The protective film 4 may be readily formed by applying a solution of tetrahydroxy silane derived by hydrolysis of tetraalkoxy silane onto the medium 3 which is rotated with the disc 1 and the layer 2, followed by drying and baking processes.
The higher the flying height of the head (i.e. the spacing between the head and the protective film surface, upon recording and reproducing of the magnetic record member), the more stable will be the record member against head-crushing. However, for the sake of recording and reproducing of the record member, a smaller spacing (spacing between the head and the surface of the record member, upon recording and reproducing) is more advantageous. For this reason, it is essential to minimize the thickness of the protective film 4. In this respect, a thickness of the order of 0.1 μm is preferable, considering the strength of the protective film 4. The range of the thickness of the protective film 4 can be taken up to 0.3 μm because the thickness exceeding the aforesaid limit of 0.3 μm causes cracking in the protective film due to stress created upon polymerization of tetrahydroxy silane. As will be described hereinafter, it is indispensable to bake the protective film 4 on the magnetic record member at a temperature more than 100° C., while the upper limit of the baking temperature depends on a thermally changing temperature of characteristics of the film medium 3. With the medium 3, uniformity of a coercive force is lost at temperatures over 300° C., thereby impairing the recording and reproducing characteristics of the record member. For this reason, the range of the baking temperatures must be set from 150° C. to 300° C. Temperatures higher than 250° C. cause magnetization in the non-magnetic alloy layer 2, resulting in a decrease in the reproduced output. However, temperatures above 250° C. will not vitally affect the above-mentioned characteristics of the magnetic record member. Also, temperatures exceeding 350° C., however, cause cracking in the record member due to a difference in thermal expansion coefficients between the alloy disc 1 and the alloy layer 2.
An amorphous inorganic material having a structure approximating that of SiO 2 glass is coated on the surface of the record member 5 as the protective film 4. The amorphous material as used herein is a kind of an inorganic high molecular compound of a net structural formula shown below in which each Si-O bond consisting of covalent bonds and Si-OH . . . O bonds consisting of hydrogen bonds are linked together three-dimensionally (This material will be referred to as polysilicate, hereinafter.): ##STR1##
The solid lines represent the covalent bonds while the broken lines represent the hydrogen bonds in the above net structural formula.
The above-mentioned polysilicate is produced by a dehydrating-condensation-polymerization of tetrahydroxy silane derived by hydrolysis of tetraalkoxy silane. The starting material for tetraalkoxy silane, i.e., tetraalkoxy silane is given in the formula of Si(OR) 4 , wherein R represents an alkyl radical, i.e. any one of methyl, ethyl, propyl and butyl radicals.
The tetraalkoxy silane is soluble in a low grade alcohol and is readily hydrolized by carboxylic acid to give the tetrahydroxy silane. This tetrahydroxy silane is highly activated so that it is difficult to isolate this from others, and is relatively highly stable in alcohol, particularly in methyl alcohol, ethyl alcohol, propyl alcohol or butyl alcohol. Upon application of an alcohol solution of tetrahydroxy silane to the surface of the magnetic metal medium 3 and upon evaporation of a solvent thereof, the polymer of the three dimensional net structural formula, i.e., polysilicate is formed as the film 4 on the surface of the medium 3 by the dehydrating condensation-polymerization of the silanol radicals Si-OH as follows: ##STR2##
In this case, unreacted silanol-radical Si-OH remains in polysilicate, thereby enhancing the adsorption and occlusion effects thereof, and the unreacted silanol radical may be reduced in amount by baking the polysilicate at a high temperature. Thus, the density of the polysilicate will be further increased. As a result, polysilicate with strong covalent bonds of Si-O may be obtained rather than with weak hydrogen bonds of a silanol radical so that the hard protective film 4 may be produced. It is desirable from the viewpoint of hardness required for the film 4 that the polysilicate is heated at temperatures greater than 100° C. On the other hand, in order to obtain a surface characteristic with a lower frictional coefficient brought about by the adsorption and occlusion effects of water or oil due to the unreacted silanol radical, it is desirable to heat the polysilicate at temperatures less than 750° C. at which level the unreacted silanol radical disappears. The infrared-absorption-spectrum analysis of this unreacted silanol radical reveals that an absorption-spectrum of the silanol radical Si-OH appears at a frequency of 3400 cm -1 , and suggests that the unreacted silanol radical is contained in the polysilicate. However, in the case where the polysilicate is baked at temperatures greater than 750° C., the infrared absorption spectrum of the silanol radical Si-OH disappears.
As will be described later, the prior-art protective film consisting of SiO 2 film prepared by the spattering process has a tendency to readily cause head-crushing compared with the protective film 4 consisting of polysilicate prepared through the process of the invention, and has a degraded surface-characteristic.
In contrast thereto, in the protective film 4 formed through the present process, the unreacted silanol radical confirmed by the infrared-absorption-spectrum analysis is included. So, film 4 has an improved surface-characteristic with a smaller frictional coefficient due to the adsorption and occlusion of water or oil into the silanol radical remaining in the film. For this reason, resistance to head-crushing, anti-abrasion property and lubricity for the magnetic record member 5 are consequently improved by using the film 4. Since an adsorbing force of water or oil into the silanol radical is so great that even if the record member 5 is heated to 200° C., there results no change in its resistance to head-crushing as well as in the anti-abrasion property.
The following examples illustrate the features of the processes for manufacturing the present magnetic record member 5, and descriptions therefor will be given in comparison with prior-art examples.
PRIOR-ART EXAMPLE 1
A disc-type aluminum alloy substrate was finished to a surface having a slight topograph using turning and heat-flattening processes. The topograph in this case should be less than 50 μm in the circumferential direction and 10 μm in the radial direction. Then a nickel-phosphorus (Ni-P) non-magnetic alloy was plated on the aluminum alloy substrate to about 50 micron-thickness. The Ni-P-plated film was then finished to a mirror surface having a surface roughness of less than 0.04 μm and a thickness of about 30 μm using a mechanical polishing process. Next, a cobalt-nickel-phosphorus (Co-Ni-P) magnetic metal alloy was plated as a magnetic memory medium on the surface of the Ni-P plated film to about 0.05 micron-thickness. SiO 2 was then coated on the surface of the Co-Ni-P magnetic metal alloy film as a protective film to a thickness of about 0.1 microns using a spattering process. Thus, a magnetic record member was obtained for a magnetic disc device.
PRIOR-ART EXAMPLE 2
A Ni-P non-magnetic alloy was plated on the surface of a disc-type aluminum alloy in a manner similar to that adopted in the prior-art Example 1. Then, a cobalt-nickel-phosphorus (Co-Ni-P) alloy was plated on the surface of the (Ni-P) non-magnetic alloy layer. Borosilicate glass of a composition shown below was then coated as a protective film on the surface of the Co-Ni-P alloy layer thus plated to 0.1 millimeter-thickness with the use of the spattering process, thereby providing a magnetic record member serving as a magnetic disc device:
SiO 2 : 50.2%
BaO: 25.1%
B 2 O 3 : 13.0%
Al 2 O 3 : 10.7%
As 2 O 3 : 0.4%
EXAMPLES OF THE PRESENT INVENTION
Example 1
A disc-type aluminum alloy was finished to obtain a surface having a slight topograph by turning and heat-flattening processes so that an alloy disc 1 of desired finish may be made. Then, a nickel-phosphorus (Ni-P) non-magnetic alloy was plated on the aluminum alloy surface to form a non-magnetic alloy layer 2 having about 50 micron-thickness. The surface of the Ni-P-plated film was polished to form a mirror finish surface, i.e., to obtain a surface roughness less than 0.04 μm and of about 30 micron-thickness using a mechanical polishing process. Then, a cobalt-nickel phosphorus (Co-Ni-P) magnetic metal alloy was plated thereon to provide a magnetic metal thin film medium 3 having about 0.05 micron-thickness. Next, a solution of a composition shown below was thoroughly mixed and filtered through a filtering film to remove precipitated SiO 2 or dust. The solution was applied onto the surface of the Co-Ni-P magnetic metal alloy layer through a spin coating process. More particularly, the disc-type aluminum alloy substrate on which the Ni-P and the Co-Ni-P film were plated in this order, was rotated at a speed greater than 200 r.p.m. (revolutions per minute) in a horizontal plane, while said solution having the above-mentioned composition was being discharged from its reservoir to the disc surface. The discharged solution was thus spread over the disc surface toward its outer periphery due to the centrifugal force. When a solvent (ethyl and butyl alcohols) of the solution discharged on the disc surface was evaporated, a polysilicate film was formed on the disc surface as the protective film 4. The disc having the protective film 4 of polysilicate of 0.1 micron-thickness was then placed at a room temperature (about 25° C.) for a while so as to evaporate the solvent of ethyl and butyl alcohols remaining in the polysilicate film. In this manner, a protective film was formed on the disc surface for the magnetic disc device.
COMPOSITION (referred to above)
Ethyl alcohol solution including tetrahydroxy
silane of eleven weight percent . . . twenty weight percent
n-butyl alcohol . . . . eighty weight percent
EXAMPLE 2
In a similar process to Example 1 of the present invention, a Ni-P film and a Co-Ni-P film were plated in this order on an aluminum alloy disc surface. Then, a polysilicate film was formed to 0.1 micron-thickness on the disc surface using the spin coating process. The disc having the polysilicate film was then baked in an electric furnace at a temperature of 100° C. for eight hours.
EXAMPLE 3
After a polysilicate film was prepared on the disc surface similarly to Example 2 of the present invention, the disc was baked in an electric furnace at a temperature of 150° C. for five hours.
EXAMPLE 4
A polysilicate film was formed on the disc surface according to a similar process to Example 2 of the present invention, and then, the disc was baked in the electric furnace at a temperature of 200° C. for three hours.
EXAMPLE 5
Similar to Example 2 of the present invention, a polysilicate film was formed on the disc surface and then, the disc was baked in the electric furnace at a temperature of 250° C. for three hours.
EXAMPLE 6
Likewise, a polysilicate film was formed on the disc surface in a process similar to Example 2 of the present invention, and next, the disc was baked in the electric furnace at a temperature of 300° C. for one hour.
EXAMPLE 7
Similar to Example 2 of the present invention, a polysilicate film was formed on the disc surface, and next, the disc was baked in the electric furnace at a temperature of 350° C. for one hour.
EXAMPLE 8
According to a process similar to Example 1 of the present invention, a Ni-P film and a Co-Ni-P film were plated in this order on an aluminum alloy disc surface. Then, a Ni-P non-magnetic alloy film of 0.4 micron-thickness was formed by the plating on the disc surface, and after this, a polysilicate film was formed thereon to 0.1 micron-thickness by means of the spin coating process. Finally, the disc was baked in an electric furnace at a temperature of 200° C. for three hours.
As has been described previously, film thickness of polysilicate of more than 0.3 μm can not be adopted because of cracking in the film.
As a result, as described in Example 8 of the present invention, the Ni-P non-magnetic alloy was plated on the surface of the Co-Ni-P magnetic thin film to a thickness of 0.4 microns. Then, polysilicate was applied onto the surface of the Ni-P non-magnetic alloy layer to a thickness of 0.1 micron so as to form a protective film of a total of 0.5 micron-thickness i.e., the total thickness of the aforesaid Ni-P non-magnetic alloy layer and the polysilicate film formed on the surface of the Co-Ni-P magnetic metal thin film.
Operation tests were given to the respective magnetic discs made according to the prior-art Examples 1 and 2 and Examples 1 to 8 of the present invention by repeating the start and stop operations during the recording and reproducing states in which each head is brought into frictional contact with the magnetic disc surface whenever the above-mentioned start and stop operations are performed. In these tests, the following observations were measured:
(1) frequencies of the occurrence of head-crushing during the repeated operation tests.
(2) variation in the reproduced output through the head due to a plurality of frictionally contacting cycles of the head and magnetic disc, and
(3) observation of the protective film-peeling due to a plurality of frictional contact cycles of the head against the magnetic disc.
In addition, measurements were made of each magnetic disc produced according to the prior-art Examples 1 and 2 and the present Examples 1 to 8 so as to check the following:
(4) variation in both reproduced output through the head and surface condition of the protective film, and
(5) uniformity of the reproduced output.
Table 1 shows the above-mentioned test results.
Table 1__________________________________________________________________________prior-art characteristicsExamples and (3) (4)Examples (1) (2) peeled environ- (5)of the present head- variation area mental variationinvention crushing in output (ratio) test in output__________________________________________________________________________prior-art once per 10% 5% no change <30%Example 1 100 cycles noticedprior-art none none none " "Example 2PresentExample 1 " " 10% -- <30%InventionExample 2 " " none no change " noticedExample 3 " " " " "Example 4 " " " " "Example 5 " " " " "Example 6 " " " " "Example 7 " " " " >30%Example 8 " " " " <30%__________________________________________________________________________
DESCRIPTION OF TEST RESULTS
Regarding characteristic (1), thirty thousand frictional contact tests of the heads against the magnetic discs given in all the examples were performed. In the course of the tests, flakes of the protective film were removed from the magnetic disc surface which caused head-crushing, and then, the tests were continued for another track of the same disc surface. However, since the magnetic disc completed by the prior-art Example 1 caused head-crushing frequently, the tests were withheld after one thousand frictional contact tests. As a result, it was found that the head of the magnetic disc in the prior-art Example 1 bit the disc surface, and continuous recording and reproducing operations become impossible at one hundred-repeated frictional contact tests of the head against the magnetic disc.
In contrast thereto, in the cases of the prior-art Example 2 and Examples 1 to 8 of the present invention, there occurred no biting of the head into the magnetic disc surface to an extent where the Co-Ni-P magnetic metal thin film medium was reached. Therefore, the recording and reproducing operations were continued normally.
Concerning the characteristic (2), a reproduced output voltage through an amplifier was observed with an oscilloscope during flying or floating movement of the head placed above the magnetic disc. Then, the comparison of an initial output with an output after thirty thousand-repeated frictional contact tests of the head against the magnetic disc was performed. The test results revealed that the magnetic discs produced according to the prior-art Example 2 and the present Examples 1 to 8 are free of any decrease in output within an accurate range of measurements. In contrast, the disc obtained by the prior-art Example 1 caused head-crushing with the result that the frictional contact tests of the head against the magnetic disc were interrupted before reaching an intended 30,000 cycles. In other words, the aforesaid operation tests were repeated to 1,000 cycles with the result of ten percent-output decrease.
As regards the characteristic (3), the frictional contact test of the head against the magnetic disc was repeated to 30,000 cycles. Next, head traces on a track on the magnetic disc surface were observed with a microscope for the measurement of peeled area of the magnetic disc surface, but no peeling was observed on the magnetic disc surface prepared by the prior-art Example 2 and the present Examples 2 to 8.
On the other hand, the magnetic disc obtained in the present invention, Example 1 had a peeled area equal to ten percent of the head contacting area on its track. However, in the case of the prior-art Example 1, the frictional contact test could not be carried out up to 30,000 cycles due to head-crushing so that the test was stopped at 1,000 cycles. The resultant peeled area was found to be about 5% of the head contacting area on its track.
As for the characteristic (4), the environmental test was carried out as follows: The environmental test consisting of two cycles of test performed at a temperature of 65° C. and at a relative humidity of 90% for four hours and of one cycle at a temperature of -40° C. (minus forty degrees centigrade) for three hours was repeated ten times. The test results revealed no change in magnetic disc surfaces prepared according to the prior-art Example 1 and the present invention, Examples 2 to 8.
It is to be noted that the environmental test was not performed for the magnetic disc prepared in the present invention, Example 1, because the disc is subjected to heating to 65° C.
For the characteristic (5), variation in reproduced output (ratio of the difference between the maximum and the minimum head-reproducing outputs obtained from the same track to the maximum output thereof) was checked. As a result, variation in the reproduced output more than thirty percent was not found in the magnetic discs of the prior-art Examples 1, 2 and Examples 1 to 6 of the present invention while variation in the reproduced output over thirty percent was found in the magnetic discs of the present invention, Example 7. This is due to the fact that the baking of the magnetic disc at a high temperature caused the lack of uniformity in characteristics of the magnetic record member.
As is apparent from the foregoing, the magnetic discs having protective films of SiO 2 formed by the spattering process as in the prior-art examples are not suitable for the magnetic record member requiring high reliability.
It was found that magnetic discs having the protective films of polysilicate given in the present examples would have high reliability within a baking temperature range of 100° C. to 300° C. as well as excellent recording and reproducing characteristics.
In addition, magnetic discs having the protective films prepared by the glass-spattering process used in the prior-art Example 2 can provide sufficiently high reliability as well as excellent recording and reproducing characteristics. However, the manufacturing yield of the conventional discs per unit hour is 1/10th that of the present magnetic discs having the polysilicate protective films produced on a mass-production basis. Also, the spattering process is accompanied with the use of a complicated vacuum system which requires the expenditure of much time and effort, and is accompanied with the use of a costly spattering apparatus for preparing a protective film on a large-size magnetic disc.
On the other hand, the polysilicate films may be formed at a low cost in such a simple manner that an alcohol solution of tetrahydroxy silane may be applied to the base disc surface using the above mentioned spin coating method, alcohol in the alcohol solution may be evaporated, and the thus obtained discs may be baked in the atmosphere. For this reason, the protective films consisting of polysilicate are excellent in characteristics required for the protective films and mass-producibility, and advantageous in manufacturing cost and freedom of size restriction on a magnetic record member.
In the aforesaid respective Examples of the present invention, the aluminum alloy disc, the Ni-P alloy layer, and the Co-Ni-P were used as the alloy disc 1, the non-magnetic alloy layer 2 and the magnetic metal thin film medium 3, respectively, with the result that the baking temperature of the protective film 4 was restricted to a temperature no greater than 300° C. However, it is apparent that by a combination use of an alloy disc having less thermal change, a non-magnetic alloy layer and a magnetic thin film medium, such a temperature restriction can be removed.
In the above-mentioned present Examples, in place of the aluminum alloy disc prepared for the disc 1, a titanium alloy may be used, which is allowed to be polished to a surface. Consequently, the non-magnetic alloy layer 2 can be omitted. Next, a magnetic metal thin film medium may be formed on the thus prepared alloy disc by the plating process, and then, a protective film of polysilicate may be formed thereon.
Moreover, in the present invention, Example 8, the Ni-P non-magnetic alloy was plated on the aluminum alloy disc surface, and then the Co-Ni-P magnetic metal thin film medium was plated on the Ni-P non-magnetic alloy polished to a desired surface finish. The Ni-P non-magnetic alloy was then plated thereon followed by the coating of a polysilicate film. Although the protective film was coated on the surface of the Co-Ni-P magnetic metal thin film medium, it is possible to form a protective film of a thickness greater than 0.3 microns by forming the polysilicate coating on the surface of the Ni-P non-magnetic alloy. More particularly, a polysilicate film of more than 0.3 micron-thickness can not be formed because of cracking, while the Ni-P non-magnetic alloy may be plated to the uniform thickness of several tens of microns. In addition, even in the case of Example 1 of the present invention in which the polysilicate film can not be sufficiently hardened, the Ni-P non-magnetic alloy and the polysilicate may be plated in this order on the surface of the Co-Ni-P magnetic metal thin film medium so as to protect the Co-Ni-P magnetic metal medium. More specifically, if a part of the polysilicate film is peeled off, the Ni-P non-magnetic alloy protects the above-mentioned thin film medium. Namely, the use of the Ni-P non-magnetic alloy alone may not adequately protect the Co-Ni-P magnetic metal thin film medium because of head-crushing caused by the Ni-P non-magnetic alloy layer. However, the Ni-P non-magnetic alloy has a close relationship with the Co-Ni-P magnetic metal thin film medium in composition and position in the periodic table. For this reason, the former may be firmly plated on the surface of the latter. Thus, if the polysilicate film which reluctantly causes head-crushing is coated on the surface of the Ni-P magnetic alloy layer, the Co-Ni-P magnetic metal thin film medium may be well protected thereby, even if a part of the polysilicate film is peeled off.
Although the present invention has been described above in conjunction with a number of Examples, various modifications and alternatives may be made within the scope of the present invention and the scope of the invention is defined by the claims and not by the examples recited hereinabove. | The thin film magnetic medium of a magnetic disc, and the read/record head employed with the disc are both protected from abusive use and physical damage as well as chemical damage (including damage due to heat and/or humidity) by a polysilicate layer, formed upon the magnetic medium. Inexpensive methods of forming the protective film (which methods lend themselves to mass production) are described. These methods are a small fraction of the cost of present day techniques. | 8 |
BACKGROUND OF THE INVENTION
This invention discloses a method and related apparatus for saving a tooth which has been exarticulated, or knocked out.
Exarticulation of a tooth, also known as an avulsion, occurs when the entire tooth is forcefully and completely knocked out of its socket. Tooth exarticulation is quite common, especially among children. Exarticulation can result from falls, violence, or other causes. It is possible to save an exarticulated tooth, but only if the proper procedures are followed. Due to public ignorance, these procedures are seldom followed. When the exarticulated tooth is brought to a dentist, it is often too late to save the tooth.
All teeth have two main components, namely the crown and the root. The crown is the portion of the tooth that protrudes from the gum, and is normally the only visible part of the tooth. The root is the portion of the tooth embedded in the gum. The entire tooth root is surrounded by the periodontal membrane, also known as the periodontal ligament. The periodontal membrane is a soft, ligamentous material which connects the tooth to its bony socket. The periodontal membrane surrounds the entire root, but does not extend onto the crown.
If the periodontal membrane of an exarticulated tooth has not been substantially damaged, and if its cells are still alive, the tooth can be successfully reimplanted in its socket. After several days, the tooth will become naturally reaffixed to the socket. But if the cells of the membrane have died, the tooth is lost.
It has been known that, if an exarticulated tooth is stored in a proper medium, its periodontal membrane can be preserved, and the tooth can be saved. Various experiments have been done to determine which media are best for storing an exarticulated tooth. One article describing such experiments is "Milk and Saliva as Possible Storage Media for Traumatically Exarticulated Teeth Prior to Replantation", by L. Blomlof, Swedish Dental Journal, vol. 5, Supp. No. 8, pages 1-26 (1981). As indicated by the title, the article describes experiments which tested the effectiveness of milk and saliva as storage media for exarticulated monkey teeth. Both of these naturally-occurring media were found to be effective in promoting the vitality of the cells of the periodontal membrane.
The above-cited article also reports the results of experiments with artificial storage media. The medium that performed best in most of the experiments is the solution known as "Eagle's medium". Eagle's medium was first described in the article by M. Eagle, entitled "Amino acid metabolism in mammalian cell cultures", in Science, vol. 130, pages 432-437 (1959). Eagle's medium has been modified by others, and is available commercially from various sources.
The other artificial medium which has been shown effective in preserving an exarticulated tooth is the Hanks Balanced Salt Solution. This solution was also used successfully in the experiments reported in the above-cited article.
Other experiments on the preservation of monkey teeth in Eagle's medium have been reported in "Periodontal and Pulpal Healing of Monkey Incisors Preserved in Tissue Culture Before Replantation", by J. O. Andreasen et al, in the International Journal of Oral Surgery, vol. 7, pages 104-112 (1978). And the Hanks solution has been further tested, and found to be effective, in experiments reported in the article by L. Blomlof et al, entitled "Effect of Storage in Media with Different Ion Strength and Osmolalities on Human Periodontal Ligament Cells", in the Scandinavian Journal of Dental Research, vol. 89, pages 180-7 (1981).
In theory, it is thus comparatively easy to preserve an exarticulated tooth, and then to reimplant it. Unfortunately, exarticulation of a tooth is a traumatic experience for the victim. If the victim is a child, the trauma can be equally severe for the parent as well. Neither parents nor children are usually well-informed about how to preserve a tooth in this kind of emergency. Very often, by the time the tooth has been carried to a dentist, the cells of the periodontal membrane have died, and it is too late to save the tooth.
The present invention provides a simple method for saving an exarticulated tooth, and also provides an apparatus which is especially useful in practicing the method. The invention makes it possible for the general public to apply the above-described scientific findings for practical benefit.
SUMMARY OF THE INVENTION
According to the invention, an exarticulated tooth is picked up by its crown, so as not to harm the periodontal membrane. The tooth is then dropped into a net, the net being attached to a rigid, or semi-rigid, basket. The basket rests in a container of a modified saline solution which tends to enhance the vitality of the cells of the periodontal membrane.
The lid of the container has a sponge means on its interior surface. The lid is screwed onto the container, and the tooth and patient are transported to the nearest dentist. The dentist opens the container, and places the lid on a working surface, so that the sponge means faces upward. The dentist then lifts the basket, with the net, from the solution, and inverts the net so that the tooth falls out onto the sponge means. The tooth is then gripped with a forceps, or other suitable tool, and reimplanted into its socket.
The basket can be constructed of metal or plastic, and is preferably equipped with a pair of handles which facilitate the lifting of the basket out of the solution. The solution is preferably a modified saline solution, such as a Hanks' Balanced Salt Solution or an Eagle's medium.
It is therefore an object to provide a method for saving an exarticulated tooth.
It is another object of the invention to provide a method for storing the exarticulated tooth, and transporting it to a dentist.
It is another object of the invention to provide apparatus which facilitates the practice of the method described above.
It is another object to provide a basket and net structure which is especially adapted for use in storing and transporting an exarticulated tooth.
It is another object to provide apparatus which can be used with commercially available media for storing and transporting exarticulated teeth.
Other objects and advantages of the invention will be apparent to those skilled in the art, from a reading of the following brief description of the drawings, the detailed description of the invention, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of the container for storing a tooth, having a basket and net, constructed according to the present invention.
FIG. 2 is an exploded perspective view showing both the basket, and the net attached to the basket.
FIG. 3 is a fragmentary cross-sectional view, showing the structure of the handles by which the basket can be lifted from the container.
FIG. 4 is a diagram of the components of a tooth.
FIG. 5 is a diagram illustrating the reimplantation of a tooth into a patient's mouth.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a simple method and apparatus for saving a tooth that has been exarticulated, or suddenly and completely knocked out of the patient's mouth.
In order to understand the invention, it is helpful to review the anatomy of a tooth. FIG. 4 is a diagram showing, in cross-section, the principal components of a single-rooted tooth. The tooth has a crown portion, designated generally by reference numeral 1, and a root portion, designated generally by reference numeral 3. The crown is the portion of the tooth which protrudes from the gingiva (or gum) 5.
The crown portion has a coating of enamel 7, under which is located a layer of dentin 9, a tubular structure which supports the enamel and provides a sensory mechanism. Pulp chamber 11 contains the nerve of the tooth. The outer covering of the root of the tooth is known as the cementum, and is designated by reference numeral 13. The periodontal membrane 15, also known as the periodontal ligament or PDL, is disposed between the cementum 13 and the bony socket 17 in which the tooth rests.
The location at which the enamel 7 abuts the cementum 13 is known as the cemento-enamel junction, and is designated by reference numeral 18. Roughly speaking, the cemento-enamel junction is the portion of the tooth where the tooth crown meets the tooth root.
The tooth shown in FIG. 4 is a single-rooted tooth. Other teeth, such as molars, have two roots, which are connected to each other. The structure of single-rooted and double-rooted teeth is otherwise the same as shown in FIG. 4.
When a tooth is exarticulated, or knocked out, the periodontal membrane generally remains with the tooth. If this membrane is undamaged, it is possible to reimplant the tooth in its socket, and, after a few days, the tooth will become firmly and naturally reattached.
The present invention includes an apparatus, illustrated in FIGS. 1-3, for facilitating the storage and transportation of an exarticulated tooth. The device comprises container 21, which can be a jar or bottle. Disposed within container 21 is basket 25 which rests on feet 23. Feet 23 can be integrally formed with the container, as shown, or they can be made part of the basket. The basket can be of wire mesh construction, or can be formed of plastic. Attached to basket 25 is net 27, which can be made of nylon, or other flexible material. The size of the net is such that it encloses a volume less than that of the container. FIG. 1 shows tooth 29 resting within net 27. For the sake of clarity, no fluid is shown in the container, in FIG. 1, but it is understood that, when the container is used to store a tooth, the interior of the container will be filled with a solution which tends to promote the vitality of the cells of the periodontal membrane.
Container 21 is closed off with lid 31. Mounted on the interior surface of lid 31 is sponge 33. The "interior surface" means the surface which is inside the container when the lid is attached to the container. The sponge helps to seal the contents of the container, although this seal need not be especially tight. The sponge has a more specific function, in the invention, as will be described below. Lid 31 is screwed onto the container, by threads 35.
A pair of handles 37, more plainly visible in the exploded perspective view of FIG. 2, are attached to the basket 25. The handles are used to lift the basket from the container. The handles shown in the figures are of the form of generally circular rings, and are pivotably attached to the periphery of the basket. The rings can be folded over each other while the lid is screwed onto the container. FIG. 1 shows handles 37 in this fully folded-down position. The view of FIG. 3 shows the movement of handles 37, as they are being opened, so as to lift the basket.
The method of the present invention can now be described. First, the exarticulated tooth is picked up from the ground. In grasping the tooth, it is important to touch only the crown portion (reference numeral 7 in FIG. 4), and not the periodontal membrane 15.
Lid 31 of container 21 is then unscrewed. The container is filled with a modified saline solution, as described below. It is possible to store the solution separately from the container, and to pour the solution into the container when needed. It may be more convenient to store the solution permanently in the container.
The tooth is dropped into the net, and into the solution. The container lid is reaffixed to the container. The container and the patient are then brought to a dentist as quickly as possible. The tooth remains gently suspended in the solution. Because the volume of the net is smaller than that of the basket, the tooth is unlikely to collide with the walls of the basket during transportation.
When the patient arrives at the dentist's office, with the container and the tooth, the dentist unscrews the lid, and places it on a flat working surface, so that the sponge faces upward. The dentist then lifts the basket, by its handles, out of the container and the solution. The basket, with the net still attached, is then gently inverted, so that the tooth falls out onto the sponge. The dentist takes a tooth extraction forceps, as illustrated by reference numeral 30 in FIG. 5, or any other equivalent implement, and gently grips the tooth 32 by its crown portion so that the tips of the forceps extend no further than the level of the cemento-enamel junction, with the apex of the root facing away from the forceps. The dentist carries the tooth, in the forceps, to the patient, who has been anesthetized, and reimplants the tooth in its socket.
FIG. 5 shows the tooth 32 being reimplanted, between teeth 33 and 34, by forceps 30. If the periodontal membrane has not been damaged during storage and transportation, it will reattach itself naturally to the socket in about 2-3 days, and the healing process is usually complete in about two weeks.
In practice, one needs a retaining means (not shown in the drawings) for holding the reimplanted tooth in place. There are many well-known ways of retaining the tooth. One way is to attach brackets to the teeth, which hold the reimplanted tooth while allowing the tooth some movement. Another method is to use a bonding material, of the type commonly used to fill chipped teeth and the like, to connect the reimplanted tooth to its neighbors. The bonding material allows the tooth to move somewhat. After the healing process is complete, the bonding material can be removed.
The only unacceptable means of retaining the reimplanted tooth is the use of a rigid bar which prevents any movement of the reimplanted tooth. Such a rigid retaining means can cause ankylosis, a condition in which the bone around the tooth becomes connected directly to the dentin, and the periodontal membrane is entirely lost.
As stated above, two preferred solutions for use in the container are the so-called Hanks' Balanced Salt Solutions, and Eagle's medium. Both of these media are are commercially available from Gibco Laboratories, of Grand Island, N.Y., and from other sources.
The Hanks solutions contain a mixture of various inorganic salts, plus certain other components. The salts found in several variations of the Hanks solutions are shown in the following table.
______________________________________Concentration in g/l Solution No.:Component: 1 2 3 4 5______________________________________CaCl.sub.2 (anhyd.) 0.14 0 1.40 0 0.14KCl 0.40 0.40 4.00 4.00 0.40KH.sub.2 PO.sub.4 0.06 0.06 0.60 0.60 0.06MgCl.sub.2 · 6H.sub.2 O 0.10 0 1.00 0 0MgSO.sub.4 (anhyd.) 0 0 0 0 0.0977MgSO.sub.4 · 7H.sub.2 O 0.10 0 1.00 0 0NaCl 8.00 8.00 80.00 80.00 8.00NaHCO.sub.3 0.35 0.35 0 0 0Na.sub.2 HPO.sub.4 0 0 0 0 0.048Na.sub.2 HPO.sub.4 · 7H.sub.2 O 0.09 0.09 0.90 0.90 0______________________________________
The Hanks solutions also contain a certain amount of glucose, for purposes of providing nutrition for the cells stored in the solution, and may also contain a coloring agent.
Solutions Nos. 3 and 4 can be characterized as more concentrated versions of Solutions Nos. 1 and 2.
Eagle's medium, in its modified forms, includes inorganic salts of the types shown in the above table, plus vitamins, amino acids, and antibiotics. More specifically, the amino acids which are used in the Eagle's medium available from Gibco Laboratories include L-Arginine, L-Cystine, L-Glutamine, L-Histidine, L-Isoleucine, L-Leucine, L-Lysine, L-Methionine, L-Phenylalanine, L-Threonine, L-Tryptophane, L-Tryosine, and L-Valine. The vitamins used in the Eagle's medium sold by Gibco include biotin, D-Ca pantothenate, choline chloride, folic acid, I-inositol, nicotinamide, pyridoxal HCl, riboflavin, and thiamine HCl. In the experiments reported in the article by Blomlof in the Swedish Dental Journal, cited above, the Eagle's medium was augmented by calf serum.
A major purpose of the Hanks solution, or Eagle's medium, or any other type of artificial solution used to store a tooth, is to provide a composition which most nearly duplicates that of the fluid in the cells being preserved. If the tooth is stored in a solution which does not match the composition of the cell contents, there will be a net inflow or outflow of ions across the boundary of the cell. This ion transport can destroy the cell. In fact, if the tooth is placed in pure water, the difference in ion concentration between the interior and exterior of the outer cells on the periodontal membrane will cause those cells to explode, thereby killing them.
Because water can kill the cells of the periodontal membrane, it is not recommended that the tooth be rinsed with water before reimplantation. Moreover, the tooth will be rinsed automatically when it is stored and transported in one of the solutions described above.
The Hanks solutions and Eagle's medium have been shown to be particularly effective in preserving the vitality of the cells of the periodontal membrane. Indeed, the experiments with Eagle's medium suggest that it is possible to store exarticulated teeth in that medium for several days without damage to the membrane. The Hanks solution appears to be effective for several hours, but it may have the advantage of having a longer shelf life than Eagle's medium.
It is quite possible that other artificial solutions can be used as well. There are many other such solutions, which are commercially available, and which have been developed for use by research laboratories for the purpose of preservation of various natural tissues. Examples include the so-called Gey's Balanced Salt Solution and Puck's Saline. However, the latter solutions are not believed to have been tested with exarticulated teeth.
The specific embodiment described above should be considered exemplary, and not limiting. The invention can be modified in many ways, within the scope of the disclosure. For example, the structure of the container can be varied, and the basket and net can assume different forms. Different types of sponge materials, and different types of closures for the container, can be employed. The basket can be made without handles, or the handles can be formed in other shapes. As described above, various balanced solutions could be used to preserve the tooth. Both the Hanks solutions and Eagle's medium represent entire families of solutions, and it is possible that other cellpreserving solutions could be substituted. These and other similar modification should be considered within the spirit and scope of the following claims. | A method and apparatus are disclosed for saving an exarticulated tooth. The tooth is grasped by its crown, so as not to harm the periodontal membrane. The tooth is then placed in a net which is attached to a basket. The net and basket are immersed in a modified saline solution which preserves the cells of the periodontal membrane. The solution is held in a container which accommodates the net and basket. The lid of the container has a sponge attached to its interior surface. The container is closed, and the tooth and patient are taken to a dentist. The dentist removes the container lid, and lays the lid on a table or other surface, so that the sponge faces upward. The dentist then lifts the basket, with the tooth, out of the solution, and inverts the net so that the tooth falls out onto the sponge. The dentist grasps the tooth with a forceps and reimplants it in the patient's mouth. | 0 |
This application is a divisional of U.S. Ser. No. 09/202,229, filed Jul. 26, 1999 now abandoned, which is a 371 of International Application No. PCT/JP97/01962, filed Jun. 9, 1997, which claims priority to Japanese Patent Application No. 8-147574, filed Jun. 10, 1996.
FIELD OF THE INVENTION
This invention relates to a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers, which is used for the work of measuring, separating, pipetting, clarifying, concentrating, diluting, observing, extracting, recovering, isolating and so on by transferring or capturing micro-substances suspended in a liquid, gas or solid, for examples, which are useful substances such as medical supplies, gene substances such as DNA etc. and immune substances such as antibody.
BACKGROUND OF THE INVENTION
So far, in such various fields as medical treatment, medicine, chemistry, physiological hygiene, sanitary, biology, food, or material and so on, it is necessary for control of a position in order to separate a target substance of assays etc. and capture the pure target substance.
For example, in the field of the medical treatment, there are such various methods of assay as chemiluminescence methods (CL method) such as an enzyme immunoassay (EIA) that utilizes an antigen-antibody reaction, a chemiluminesence immunoassay (CLIA) in a narrow sense in which a chemical illuminescent compound is used for marking as a tracer for immunoassay, and a chemilluminescent enzyme immunoassay (CLEIA) which detects enzyme activity with high sensitivity by using a chemical luminescent compound in a detection system.
As an inspection method, using any of the techniques as described above, there have been known the magnetic particles method using magnetic particles each having a surface coated with an antigen or an antibody, the latex method using latex having a surface coated with an antigen or an antibody, the beads method using spherical beads (non-magnetic) each having a surface coated with an antigen or an antibody, or the so-called tubecoating method using cells each having an inner wall coated with an antigen or an antibody. When taking into account efficiency of capturing an antigen or an antibody as well as production cost and running cost, however, methods using magnetic bodies such as magnetic particles or beads are far more advantageous.
Incidentally, when the magnetic particles per se hold micro-substances, the less the size of each magnetic particle is formed, the more the quantity of the micro-substances can be captured by whole the magnetic particles, on the condition that the total mass or volume of whole the magnetic particles is fixed. Because, reduced size of magnetic particle results in increase in the ratio of surface to volume. As a magnetic charge per a magnetic particle is reduced and an influence of the magnetic field on each magnetic particle is reduced certainly in this case, however, there has been a problem that an attraction becomes weaker and the control of magnetic field becomes more difficult.
On the other hand, if a volume of each magnetic particle increases, the influence of the magnetic field to each magnetic particle enhances, the attraction becomes stronger, and a control of magnetic field becomes easier. On the condition that the total mass of the magnetic particles is equal, however, there has been a problem that the magnetic particle is hard to capture micro-substances and the efficiency in capturing micro-substances decreases.
Furthermore, capturing substances on magnetic particles per se requires such treating as coating and so on. Particularly, there has been a problem that to treat the surface of magnetic particle per se optionally so as to enhance the efficiency in capturing micro-substance is technically and costly difficult.
It is a first object of the present invention to provide an improved carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers, therefore.
It is a second object of the present invention to provide a general-purpose carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can hold various substances that can not directly affected by remote forces, and that can not directly be bonded to magnetic particles, and can hold various remote-acting bodies, so that diverse inspections and so on can be executed for various target substances.
It is a third object of the present invention to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which combines a low-cost carrier which is superior in capturing target substances and is easily treated but has not a remote operating character, with remote-acting bodies which are superior in remote operating and controlling, without necessity of depending upon magnetic particles having an extraordinary particular surface or substance for capturing target substances, and, which needs not treat the magnetic particles per se, is produced at low cost, is easy to operate remotely, has a super capturing-ability, can efficiently and promptly process with high precision in determining quantity, and is easy to be dealt with.
It is a forth object to provide a carrier holding micro-substance, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can execute various actions and precision and complex controls by reliable remote operating.
It is a fifth object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling the positions of such carriers which is chemically stable, has not bad-influence upon target substances of inspections for living things, and is reliable.
It is a sixth object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can easily separate a target substance from the remote-acting bodies such as magnetic particles, collect and recover only the pure target substance, and change concentration.
It is a seventh object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can treat plural suspension systems without mixing these systems, can establish a uniform state, and can transfer and carry the useful substances (such as antibiotic and so on) to destination without contamination.
It is an eighth object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can effectively be available to easy and rapid process of test-analysis for useful substances, extraction-analysis for gene substances (DNA and so on), and detection-analysis for immune substances, and, can contribute to automatizing a clinical test.
It is a ninth object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can prevent from clog and so on and improve the efficiency of filtration and absorption by using the carriers as auxiliary chemicals of filter and absorption, controlling the density of carriers with disposition and direction of magnetic field.
It is a tenth object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can safely, easily, and automatically transfer a target substance between reaction vessels in order, in the case of a multistage chemical reaction.
It is an eleventh object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can easily, rapidly, and automatically inspect the efficient concentration of antibiotic by easy and rapid test with absorbing the biological active substance (such as antibiotic) or test bacterium (such as antibiotic test bacterium: a colon bacillus) to the carriers, or cultivating them in the carriers.
It is an twelfth object to provide a carrier holding micro-substances, system suspending such carriers, apparatus for manipulating such carriers and method of controlling positions of such carriers which can cultivate, recover, concentrate, or analyze substances (such as iron filings, dust, environmental pollution, food pollution, addition), microorganisms or cells of plants and animals.
SUMMARY OF THE INVENTION
According to a first aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances comprises a carrier holding one or more remote-acting bodies capable of being manipulated for positions thereof by a remote force, and one or more micro-substances containing a target substance of an assay and so on in the surfaces of the carrier, wherein positions of micro-substances are controlled by a remote manipulation of the remote-acting bodies which are held together with micro-substances in the surfaces of the carrier.
Here, the micro-substances include a target substance for an assay, a test, multiplication, or extraction and so on. The micro-substances are not limited to the target substance, but can include other substances such as marker substances or intervene substances and so on.
The target substance, the intervene substance or the other substance is not always limited to a single kind. A size of the micro-substance is not always limited to a fixed one. But, for example, it may be about 0.1 μm to 1 mm. Furthermore, the micro-substances include living bodies, namely, such micro-organisms as bacteria, or viruses.
The “remote-acting body” is the one whose position can be manipulated by such remote force generated by a magnetic field, an electronic field, light, temperature gradient, and pressure gradient, sonic wave and so on. For example, as the remote-acting bodies, magnetic particles are used for the magnetic field, charge particles or dielectric substances are used for the electric field, particles having an air bubble or an endothermic element capable of rising by a buoyant force generated in volume heated and expanded by ray or heat are used for light or temperature field, or moving bodies by vibration with applying super sonic wave or pressure wave, are used. The remote-acting body is not always manipulated by a single kind of force. Such a remote-acting body as a charged magnetic substance can be manipulated by various kinds of remote forces. Micro-organisms may be used as the remote-acting bodies.
The “carrier” is capable of holding remote-acting bodies and micro-substances in the surfaces thereof. They are held by fixing, adsorption, adhesion, or reaction with a reaction substance coated thereon.
The size of the remote-acting body or the carrier is not necessarily fixed. It is the same orders as the micro-substance, for example, about 0.1 μm (100 nm) to about 1000 μm(10 6 nm=1 mm).
“Control of position” includes in addition to control of transferring, control of collecting, oscillating, rotating, capturing, speed, separating, suspending, or cleaning. The present invention satisfies both superior remote-acting ability and superior capturing ability, by holding a remote-acting body or bodies such as magnetic particles etc. and micro-substances in the carrier. Hence, the present invention can enhance efficiency of assay and so on, and can quickly execute a processing with high precision in deciding quantity, at low cost, without trouble. Various movements, and precision and complex controls are executed by remote-acting operation of the present invention. The present invention provides the carrier holding micro-substances, which can transfer and carry such useful substances as medical supplies (immune substance and so on) to the destination, without contamination.
According to a second aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the carrier holds the remote-acting bodies and micro-substances by fixing a plurality of holes, cavities, concavities or convexities, adsorption or adhesion in the surface per se, reaction by a prescribed reaction substance coated thereon, or combination therewith.
Here, “holes, cavities” include in addition to dips-like in surfaces, the ones penetrating the carrier such as porous cavities which include the one such as fiber or gel. Also, “holes, cavities, concavities or convexities”, coating and so on may be not always formed in the carriers. Fixing, adsorption, adhesion, or, reaction may be done not only in the surfaces or the carrier, but also in the surfaces of the micro-substance or remote-acting substance. For instance, the carrier may be held in holes formed in a bigger remote-acting body, and the micro-substances are held in the carrier further.
“Fixing” means to hold mainly by a mechanical force such as a friction. For example, it includes the meaning to hold by inserting or slipping into holes and so on. To be able to capture micro-substances and so on by fixing, an affinity between the carrier and micro-substances and so on in fixing is necessary. The affinity can mainly be determined by the size of micro-substance, remote-acting ability, size of remote-acting bodies, or size of holes, cavities, concavities or convexities.
“Adsorption” means the phenomena that substances in gas phase or liquid phase reach to an equilibrium at different concentration from that of the inside phase, on the surface between one phase and the other contacting phase. The word, adsorption includes physical adsorption and chemical adsorption. Here, it is used in such a broad meaning as adsorption by various reactions or electromagnetic forces. Further, adsorption by reaction or electromagnetic force includes various modes such as absorption by electrostatic force (Coulomn force), magnetic force or intermolecular force as van der Waals' force, hydrogen bond, ionic bond, or covalent bond.
“Reaction” includes agglutination (reaction of solidification). Reaction can bond only solidified target substance and can remind non-solidified substances in liquid without bonding. “Adhesion” means to hold by using an adhesive power of adhesives and so on. “Reaction by a prescribed reaction substance coated thereon” includes, for example, antigen-antibody reaction. In this case, a target substance is an antigen that is captured by this reaction, and the carrier is coated by an antibody reacting with the antigen.
In the case that DNA substance is a target substance, the DNA substance can be captured with the reaction of hydrogen bond, by the carrier coated by basic ingredients (adenin←→thymine, guanine←→cytosine) which is complementary to the basic ingredients of the DNA. Coating may be formed on micro-substances or remote-acting bodies, instead of the carrier. Furthermore, whole the surfaces are not always covered with coating. It follows from “combination therewith” that fixing and absorption can exist together and that the absorption can be done on the surfaces of micro-substances fixed to the carrier, for instance.
In FIG. 1 ( a ) ( b ), enlarged micro-substances-holding-carriers are imitatively exemplified, which are of various shapes or of indefinite shapes and are held by remote-acting bodies and micro-substances. FIG. 1 ( a ) shows a micro-substances-holding-carrier 5 , which holds remote-acting bodies 3 and micro-substances 4 in a plurality of holes 2 of the fibrous carrier 1 . FIG. 1 ( b ) shows a micro-substances-holding-carrier 10 , which holds remote-acting bodies 13 and micro-substances 14 in a plurality of holes 12 of the spherical carrier 11 . The shape of the carrier may include torus and so on, in addition to these shown shapes. Thus, as remote-acting body and micro-substance can be held in the carrier in various way, inspections for various substances can be executed.
According to a third aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the carrier is formed by organic substances such as high molecular compounds, inorganic substances such as ceramics or metals or, living bodies.
Here, “high molecular compounds” include fibrous substances and synthetic resins. The present invention is capable of executing various controls or inspections and so on, because various carriers can be selected according to the purpose of inspections etc. or used kinds of substances.
According to a fourth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the carrier is made of fibrous substance such as cellulose.
Here, “fibrous substance” includes a synthetic fibrous such as nylon etc. in addition to the cellulose. As the surfaces of fibrous substance such as cellulose have a plurality of cavities, concavities, convexities or holes, the surfaces can capture various substances. The present invention has not only above-mentioned effect, but also the effect that is capable of using for various purposes. Because the fibrous substance such as cellulose and so on is chemically stable, and can be used for suspension of various substances. Also, the fibrous substance is easy to be treated, and can be treated at low cost. The fibrous substance is light, and can easily be controlled. Cellulose may be formed to be torus-like or fibrous-like as well as spherical-like.
Furthermore, since the surfaces of fibrous substance such as cellulose etc. have holes or cavities and so on, fibrous substance needs not be treated by coating of predetermined substance etc. on the carrier, so as to capture target substances. Fibrous substances can easily capture these substances by agitating or suspending with the remote-acting bodies and micro-substances, can easily construct the carriers holding micro-substances, and can satisfy both ability of capture and remote-acting ability.
Consequently, the reliable carriers holding micro-substances are promptly provided at low cost, without requiring much labor. As the fibrous substance like cellulose is easy to be treated, treatment for improving capturing efficiency can easily be done at low cost.
Further, in the present invention, micro-substances can be separated from the carriers once held by remote-acting bodies and micro-substances. For example, when the carrier is cellulose, the carrier can be excluded by dissolving the cellulose with making use of enzyme in a concentration process of micro-substances.
According to a fifth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein micro-substances include one or more kinds of intervene substances through which said target substances or the remote-acting bodies are held in the carrier.
The present invention is capable of holding the substances that can not directly be bonded to the carrier, in the carrier. For example, if the carrier is apt to bond the antigen and is hard to bond the antibody, it is appropriate that the carrier can capture antigen through the antibody held on the carrier. Therefore, the present invention can apply to the various substances.
According to a sixth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substance, wherein the micro-substances include auxiliary substances such as marker substances and so on.
The present invention facilitates to analyze inspections and so on, and is capable of accelerating or delaying reactions in inspections and executing various processing. “Auxiliary substances” include catalyst substances for accelerating inspections and so on, in addition to said marker substances. Furthermore, the auxiliary substances may indirectly be held in the carrier through target substances and so on, without bonding the carrier directly.
According to a seventh aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the remote-acting bodies are made of magnetic substances. Hence, the present invention can easily execute a reliable and precision control superior in remote-acting operation, at low cost.
Here, “magnetic substance” includes para-magnetic substance or ferro-magnetic substance, which receives a virtue of a magnetic field. The magnetic substances include the one having spherical shape of big diameter or micro-particles like a grain, and the diameter is not necessarily fixed. The shape is not limited to the spherical one. These shapes can be applicable to the case of the charged body, dielectric body or transparent body and so on as mentioned below. Thus, the present invention can faithfully and reliably control positions at low cost, with excellent remote-acting ability.
According to an eighth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the remote-acting bodies are made of charged bodies or substances having a different dielectricity from that of the surrounding suspended system. “Charged body” means the one having charge. For example, it includes a ferro-dielectric body having a spontaneous dielectric polarization without an electric field. The dielectricity of the remote-acting bodies is different from the suspension system around them and is higher or lower than that of the systems. As the charge body of lower dielectricity has an opposite polarity from the higher one, it moves in opposite direction to the electric field. Consequently, the present invention can execute easy, reliable and precision control of remote-acting operations. Furthermore, the present invention is capable of various and easy controls by combining with various remote-acting bodies.
According to a ninth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the remote-acting bodies are micro-organisms having such taxis as lumino-taxis or magno-taxis. Here, for example, “magno-taxis micro-organisms” include micro-organisms such as cells or bacteria etc. in which magnetic substances are artificially or naturally contained. When micro-organisms are used, it is necessary that the other substances do not affect a bad influence to the micro-organisms, or, the micro-organisms do not affect the other substances conversely. The present invention can easily use micro-organisms without treating substances, and can have the micro-organisms move complicatedly.
According to a tenth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substance, wherein the remote-acting bodies are expandable particles whose volume changes in accordance with temperature or pressure. For example, a substance having a high thermal expansion coefficient can easily transfer upward or downward by expansion or contraction according to rising temperature or pressure of whole the suspension system, at low cost. The expandable particles are the one enclosed a gas susceptible to expand and contract compared with the surrounding liquid therein.
According to an eleventh aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substance, wherein the remote-acting bodies are made of transparent substances or opaque substances. The carrier holding the remote-acting particles and so on in one united body can cause to be moved or trapped (laser trap) by irradiating a laser to transparent particles used as remote-action particles, for example, such as polystyrene latex, or silica micro-particles. Or, the carrier in one united body can cause to be moved upwardly or downwardly by irradiating the laser to opaque particles or not, so as to expand or concentrate by heat.
According to a twelfth aspect of the invention, the above mentioned objects are achieved by providing a carrier holding micro-substances, wherein the remote-acting bodies are magnetic particles and the carriers are made of cellulose.
The size of the carrier is determined according to the purpose of the assay etc., the kinds or sizes of a target substance, magnetic particles to be held and suspension systems. As the present invention can provide the carrier holding micro-substances which has both superior remote-acting ability and superior capturing ability, the present invention can efficiently, rapidly and reliably execute inspection at low cost.
According to a thirteenth aspect of the invention, the above mentioned objects are achieved by providing a system suspending carriers holding micro-substances is suspension of remote-acting bodies, micro-substances and the carriers which are described in the first to the twelfth aspects of the invention in a liquid, a gas or a solid. “Solid” includes, for example, such gel-like substance as alginic acid, paste, agaragar-like substance and so on. As the present invention can provide the carrier holding micro-substances which has both superior remote-acting ability and superior capturing ability, the present invention can efficiently, rapidly and reliably execute the assay, at low cost.
Furthermore, in the present invention, the carriers holding micro-substances are capable of various movements and precision and complicated controls by sure remote-acting operation. And the present invention provides the carrier holding micro-substances which can move and carry such useful substances as medical supplies (antibody and so on) to the destination, without contamination.
The present invention can analyze and test the useful substances, and can extract and analyze the gene substance (DNA and so on), and detect the immune substance (antibody etc.) and so on.
According to a fourteenth aspect of the invention, the above mentioned objects are achieved by providing a system suspending carriers holding micro-substances, wherein the carrier is a sterilized cellulose-carrier having a plurality of cavities or holes, the remote-acting bodies are sterilized magnetic particles, micro-substances contain micro-organisms being target of an assay and sterilized reductive enzyme used as a marker substance, and the liquid is a sterilized liquid culture medium.
Here, the size of the cavities or hole is large enough to be able to perform orientation of magnetic particles and be able to control positions of carrier holding micro-substances by magnetic field. For example, diameter of the hole is about 10 μm in the case of the cellulose carrier of about 150 μm. Thus, even if a magnetic particle is small, the positions of carrier can be controlled as long as holes with size being large enough to perform orientation to accept the influence of the magnetic field and bond the magnetic particles. “Cellulose carrier” includes the one made of cellulose or the one such as cellulose acetate made from cellulose.
The present invention provides with the carrier holding micro-substances, which satisfies both remote-acting ability and capturing ability, is chemically stable, does not affect target substances such as living things for assays and so on, is reliable, and is capable of being selected diversely according to target substances. Furthermore, the carrier holding micro-substances can transfer and carry a useful substance such as medical supplies (antibiotic and so on) to the destination without contamination.
The present invention can effectively utilize for easy and rapid processing of inspection and analyze of useful substances, extraction and analyze of gene substance (DNA and so on), and inspection and analyze of immune substance (antibody) and so on, and can contribute to the automatic performance of the clinical inspection and so on.
Furthermore, such substances and cells that can be adsorbed to the carriers can be recovered and concentrated by making use of orientation in magnetic field.
According to a fifteenth aspect of the invention, the above mentioned objects are achieved by providing a system suspending carriers holding micro-substances, wherein the carrier is a cellulose-carrier having a plurality of cavities or holes, the remote-acting bodies are magnetic particles, and micro-substances are antibiotics or anticancer substances.
Here, the size of each substance is various according to kinds of the suspension systems. For example, the carrier is the sphere having a diameter of about 100 μm, the cavities or holes have a dimension of about 10 μm, the magnetic particles are about 1 μm, and the concentration of the carriers in liquid is about 1000 sphere/cc. If kanamycin is used as an immune substance, the concentration of the carriers is about 1000 sphere/cc.
The present invention has not only the above mentioned effects, but also has effects being chemically stable, affecting no bad influence to target substances for inspection etc., being reliable, and enabling to select appropriate substances variously according to target substances and so on.
Furthermore, the carrier holding micro-substances can transfer and carry useful substances such as medical supplies (antibiotic and so on) to the destination, without contamination.
The present invention can effectively utilize for easy and rapid processing of inspection and analyze of useful substances, extraction and analyze of gene substance (DNA and so on), and inspection and analyze of immune substances (antibody) and so on, and can contribute to the automatic performance of the clinical inspection and so on. Furthermore, such substances and cells that can be adsorbed to the carriers, can be recovered and concentrated by making use of orientation in magnetic field.
According to a sixteenth aspect of the invention, the above mentioned objects are achieved by providing a suspension system for carriers holding micro-substances, wherein the remote-acting bodies and the carriers are used as filtering auxiliary chemicals for filtering so that micro-substances being hard to filter can be filtrated.
The present invention makes filtrating separation be more reliable, less contaminated, and less laborious than a filter. The present invention causes micro-substances that are hard to be filtrated, to facilitate to be filtrated surely by suspending the remote-acting bodies and carriers. The present invention can improve the efficiency of adsorbing and filtrating by using the carrier as auxiliary chemicals for adsorbing and filtering, by utilizing orientation by magnetic field, by controlling the density of carriers, and by avoiding clog and so on. Furthermore, the present invention can execute multi-stage chemical reactions by transferring the carriers between containers in order, safely, automatically and easily.
According to a seventeenth aspect of the invention, the above mentioned objects are achieved by providing an apparatus for manipulating carriers holding micro-substances comprises a container accommodating the suspension system or a liquid passage passing the suspension, and remote-manipulating means mounted out of the container or the liquid passage to manipulate the remote-acting bodies in the container or the liquid passage remotely.
Here, “the liquid passage” is the one which a liquid passes through, and “container” is the one which accommodating a liquid. The carrier holding micro-substances combines the remote-acting bodies having superior remote-acting ability with the carriers having superior capturing-ability, can satisfy the characteristics of superior remote-acting ability and superior capturing-ability, and can efficiently and rapidly treat assay and so on, with high precision in quantity.
Furthermore, the present invention enables various movements and precision and complicated controls by sure remote-acting operation. Also, the present invention provides the carriers holding micro-substances that can transfer and carry such useful substances as medical supplies (immune substances and so on) to the destination, without contamination. The present invention can effectively be utilized for easy and rapid processing of inspection and analyze of useful substances, extraction and analyze of gene substance (DNA and so on), and inspection and analyze of immune substances (antibody) and so on.
According to an eighth aspect of the invention, the above mentioned objects are achieved by providing an apparatus for manipulating carriers holding micro-substances, wherein the remote-manipulating means is a magnetic source such as a permanent magnet or a solenoid generating magnetic field to be applied to the remote-acting bodies. The apparatus can faithfully, surely, and efficiently control, and can not only transfer, separate or collect the carrier, but also agitate or clean.
According to a nineteenth aspect of the invention, the above mentioned objects are achieved by providing an apparatus for manipulating carriers holding micro-substances, wherein the remote-manipulating means is one or more electrodes which alternative current or direct current voltage is supplied when the remote-acting bodies are made of charge bodies or dielectric bodies, and is a controllable heat source or a pressure control means when the remote-acting bodies are expandable particles whose volume change, in accordance with temperature or pressure.
In the present invention, the apparatus can not only transfer or collect the carriers, but also can surely and efficiently agitate or clean by driving the remote-manipulating means. “Alternating current voltage” which has a fixed high frequency, prevents from generating electrode reaction (electrolysis).
In the present invention, the apparatus can be used for electrophores from one electrode to another electrode. Here, two electrodes are oppositely arranged so that the container is put between the electrodes, and the one electrode is formed to be sharp. Besides, the direction for movement of carriers in electrophores depends upon whether the dielectricity of the dielectric body is lower or higher than the surrounding liquid or gas.
Furthermore, the present invention can make the carriers move mainly up and down by the expandable particles. Consequently, the present invention can easily control the movement of the remote-acting bodies at low cost. Also, the present invention enables various controls by combining various kinds of remote-acting bodies.
According to a twentieth aspect of the invention, the above mentioned objects are achieved by providing an apparatus for manipulating carriers holding micro-substances, wherein the remote-manipulating means is an optical source such as a laser ray or an infra-red ray and so on when the remote-acting bodies are micro-organisms having lumino-taxis, or transparent or opaque substances.
The present invention, the apparatus can draw the carriers close near focal points having high energy density by irradiating a ray such as laser to the transparent substance and can transfer the carriers by moving the irradiation of the ray. Besides, in the present invention, the apparatus can easily control positions of the carriers by irradiation the laser and so on to the opaque substance, and giving heat to expand the volume. Furthermore, the present invention can easily execute complicated controls of the position of carriers by using micro-substances, without labor for treating.
According to a twenty-first aspect of the invention, the above mentioned objects are achieved by providing an apparatus for manipulating carriers holding micro-substances, wherein plural kinds of remote-manipulating means are mounted. The present invention can execute various and complicated controls according to the used substances or purpose, for instance, by combining magnetic field with electric field and so on.
According to a twenty-second aspect of the invention, the above mentioned objects are achieved by providing a method of controlling a position of carrier holding micro-substances comprises the steps of: pouring remote-acting bodies for. positions thereof to be manipulated by a remote force, micro-substances including target substances of an assay and so on, the carriers capable of holding micro-substances and the remote-acting bodies, into a liquid, a gas or a solid in accordance with a predetermined order, agitating the suspension to hold micro-substances and the remote-acting bodies in the carriers, controlling positions of the carriers holding micro-substances and the remote-acting bodies in the surfaces thereof by applying a remote force to the remote-acting bodies.
Here, “a predetermined order” is variously determined according to the remote-acting bodies, micro-substances or carriers to be used or the purpose of the kinds of the inspections. For example, in the first embodiment, the magnetic particles are poured into lastly, because bonding between magnetic particles and the carrier may prevent from bonding between bacteria and the carrier. Besides, “agitating” increases the opportunity of encounter among carriers, remote-acting bodies and micro-substances, and contributes to insertion of the micro-substances and so on into the holes and so on of the carriers and promotion of construction of the carriers holding micro-substances.
The present invention can easily, reliably and rapidly execute assays and so on without manpower, at low cost, because carriers holding micro-substances can be constructed in the suspension during process, and need not be treated for the constructions beforehand.
In the present invention, the carriers holding micro-substances can satisfy both superior remote-acting ability and superior capturing ability by combining the remote-acting bodies having superior remote-acting ability with the carriers having superior capturing ability, and can efficiently and rapidly execute assays and so on, with high precision in determination on the quantity.
Furthermore, in the present invention, the carriers holding micro-substances are capable of various movements, and precision and complicated controls. The present invention provides with the carrier holding micro-substances that can carry and transfer such useful substances (immune substances and so on) as medical supplies to the destinations without contamination. The present invention can effectively utilize for processing of, inspection and analyze of useful substances, extraction and analyze of gene substances (DNA and so on), and inspection of immune substances (antibodies) and so on.
According to a twenty-third aspect of the invention, the above mentioned objects are achieved by providing a method of controlling positions of carrier holding micro-substances, wherein the remote-acting bodies, micro-substances and carriers are described in the second to the twelfth aspects. The present invention can execute inspections and so on with respect to various substances, in various modes.
According to a twenty-fourth aspect of the invention, the above mentioned objects are achieved by providing a method of controlling positions of carriers holding micro-substances, comprises the steps of: pouring a sterilized reductive enzyme, such micro-organisms such as bacteria or viruses being a target substance of an assay and so on, and sterilized cellulose-carriers in a sterilized liquid culture medium, pouring magnetic particles in the liquid culture medium, agitating the liquid suspended by them, controlling positions of the micro-organisms and so on by applying or removing a magnetic field.
Here, the present invention uses the sterilized liquid culture medium, the sterilized reductive enzyme, and the sterilized magnetic particles, in order to inspect existence of micro-organisms, measure the quantity of micro-organisms, and extract DNA/RNA from micro-organisms. The reductive enzyme is used for detection of the existence of micro-organisms. For example, T.T.C. that is used as a reductive enzyme, makes insoluble coloring matter by reduction.
According to a twenty-fifth aspect of the invention, the above mentioned objects are achieved by providing a method of controlling positions of carriers holding micro-substances, comprises the steps of: pouring cellulose-carriers having a plurality of cavities or holes, magnetic particles, and micro-substances such as antibiotin or anticancer substance, agitating the liquid suspended by them, controlling positions of the carriers holding micro-substances and the remote-acting bodies in the surfaces thereof by applying or removing a magnetic field to or from the remote-acting bodies.
The present invention has in addition to the above effect, such merits that it is chemically stable, it affects no bad influence to the target substances for assay etc., it is reliable, and it is capable of being selected variously according to the target substances and so on.
Furthermore, the carrier holding micro-substances can transfer and carry the useful substances such as medical supplies (antibiotic and so on) to the destination, without contamination. The present invention can effectively utilize for easy and rapid processing of inspections and analyze of useful substances, extraction and analyze of gene substances (DNA and so on), and inspections and analyze of immune substances (antibody) and so on, and can contribute to the automatic performance of the clinical inspection and so on.
Furthermore, such substances and cells that can be adsorbed to the carriers, can be recovered and concentrated by making use of orientation in a magnetic field.
According to a twenty-sixth aspect of the invention, the above mentioned objects are achieved by providing a method of controlling positions of carriers holding micro-substances, comprises the steps of: pouring micro-substances being hard to be filtered, remote-acting bodies, and carriers into a liquid, agitating the liquid suspended by them, controlling so as to use the remote-acting bodies and carriers as auxiliary chemicals for filtration by applying or removing a magnetic field to of from the liquid.
The present invention makes a filtrating separation be more reliable, less contaminated, and less laborious than a filter. The present invention enables micro-substances that are hard to be filtrated, to be filtrated easily and surely by suspending the remote-acting bodies and carriers.
The present invention can improve the efficiency of adsorbing and filtrating by using the carrier as auxiliary chemicals for adsorbing and filtering, utilizing orientation by magnetic field, controlling the density of carriers, and avoiding clog and so on. Furthermore, the present invention can safely, automatically and easily execute multi-stage chemical reactions by transferring the carriers between containers in order,.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an enlarged schematic illustration of the carrier holding micro-substances of the first embodiment of the invention.
FIG. 2 is an enlarged fragmentary schematic illustration of the carrier holding micro-substances of the first embodiment of the invention.
FIG. 3 is a flowchart of the first embodiment of the invention.
FIG. 4 is a flowchart of the second embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the invention will be described below.
The first embodiment relates to an example of Rapid Minimum Inhibitory Concentration Measure.
As shown in FIG. 2 , this embodiment uses a magnetic particle 33 as a kind of remote-acting bodies whose positions can be manipulated by a remote-acting magnetic field, bacteria 34 as a target substance of an assay, and a sterilized C.C. (cellulose carrier) 31 capable of holding said magnetic particles 33 and bacteria 34 in the surface thereof as the carrier.
The bacteria of more than about 100 CFU (colony forming unit)/ml are prepared, in consideration of accuracy in measuring. Those substances are separately prepared beforehand, then suspended in a liquid. A sterilized liquid culture medium 30 is prepared as a liquid for suspension, and the magnetic particles 33 , bacteria 34 and C.C. 31 are poured in and suspended.
Furthermore, in this suspended liquid, sterilized T.T.C. (tetrazolium chloride, or tetrazolium bromide and so on) 35 whose quantity is 0.05% of the liquid culture medium is suspended therein. In the present embodiment, the liquid culture medium, for example, a sterilized (or bioclean) culture medium (sterile medium), for example, Müller Hinton (M.H.), nutrient, heart-infusion (H.I.), and so on, is prepared in a container.
In the present embodiment, the assay is executed by a sample distributor comprises, for example, as shown in FIG. 2 , one or more well-plates 21 accommodating a liquid, a pipette tip P having a front end portion 25 tapered off toward the front end, a reservoir portion 22 with a greater diameter than the front end portion 25 , a liquid passing portion 23 slightly narrower than the reservoir portion 22 , and a separation region 23 a in the liquid passing portion 23 subjected to an action of a magnetic field; a sample distribution unit (not shown) having a nozzle N removably fitted into an cavities of the reservoir portion 22 to apply a negative or positive pressure into the pipette tip P to draw or discharge a liquid into or from the pipette tip P; a magnet (M) 24 arranged so that it can be brought close to or away from the liquid passing portion 23 ; and a control device (it is not shown in drawings) for controlling the operation and movement of the sample distribution unit, the attaching and detaching of the pipette tip P to and from the nozzle N, and the bringing of the magnet 24 close to or away from the pipette tip P.
Besides, in FIG. 2 , reference numeral 26 shows an edge part to have hardness to the opening of the reservoir portion 22 . Said sample distribution unit is detachably mounted at the upper end of pipette tip P, is connected with pipette tip P, and is such a mechanism for drawing and discharging liquid as a cylinder. It is needless to say that the shape of the pipette tip P is not limited to the one shown in drawing. As far as the micro-substances-holding carriers 40 are surely collected by magnet 24 , any shapes may be used. In order to collect by the magnet completely, it is preferable that the diameter of the section the magnet attached or detached is formed to be thinner and the speed of drawing or discharging is controlled so as to increase attracting-efficiency.
The magnetic field generated by the magnet 24 is strong enough to attract and maintain C.C. 31 holding the magnetic substances 33 and bacteria 34 on the wall of the liquid passing portion 23 of the pipette tip P, and does not affect C.C. 31 holding magnetic particles 33 in the case that the magnet 24 is farthest away from the pipette tip P. Further, in FIG. 2 , micro-substances-holding-carriers 40 and so on in the well-plate 21 is enlarged for convenience's sake.
Next, the processing of the present embodiment is described.
In FIG. 3 , at step S 1 , the liquid culture medium, for example, the sterilized culture medium (Sterile Medium), for example, Müller Hinton (M.H.), nutrient and so on is accommodated in the well-plate 21 . Sterilization is performed by an autoclave for about twenty minutes at temperature of 120° C.
At step S 2 , said T.T.C. 35 which is the reduced substance sterilized by Milipore-filter is poured into the liquid culture medium 30 , as a marker substance, so as to be 0.05% (ratio of capacity).
The T.T.C. 35 sticks on bacteria. If the bacteria stuck by T.T.C. 35 take oxygen in, Formazan which is an insoluble red coloring matter is generated by reductive power of bacteria. Therefore, the quantity of bacteria can be detected by measuring that of the red coloring matter. Thus, as T.T.C. 35 is apt to turn red by heat, T.T.C. 35 is sterilized by Milipore filter without heat.
At step S 3 , the bacteria (or micro-organisms including viruses and so on) of 100 CFU (Colony Forming Unit)/ml of bacteria 34 are poured into the liquid culture medium 30 . This quantity of bacteria is determined so as to be necessary for keeping measuring accuracy above a fixed level.
At step S 4 , furthermore, said cellulose carriers (C.C.) sterilized by using ethylene oxide gas, are distributed by the pipette tip P. Here, said cellulose carrier (C.C.) 31 has a sphere whose diameter is about 150 μm and has a plurality of holes 32 whose diameter is about 10 μm, in the sphere. The hole is large enough for the magnetic particles held therein so as to be able to cause the orientation by the magnetic field from the magnet 24 . Also, the cellulose carrier 31 has a charge of 1.16 meq./g. Namely, in the present embodiment, the carriers are capable of holding micro-substances and so on by both fixing in holes 32 and Coulomb force of the charge. Also, for example, the number of the C.C. 31 is determined to be 100 sphere/ml, so that the bacteria of 1 CFU can be held in each C.C. 31 .
At step S 5 , a plural solutions of antibiotics used as samples, whose concentration is each 200, 100, 50, 25, 12, 5, 3, 0 γ/ml, is prepared in different containers (micro-plate). The suspended liquid obtained at step S 4 is distributed into each container by the pipette tip P.
At step S 5 a , the suspended liquid accommodated in each container is cultivated at temperature of 37° C. for 6–8 hours. This cultivation is executed in order to increase the number of the bacteria up to being enough to measure. If the sufficient quantity of bacteria is prepared beforehand, this step is not necessary. The cultivation is executed in the state that Milipore filter that passes Oxygen but does not pass vapor, is put on the container, in order to prevent from invading various kinds of germs.
At this stage, a mixer is driven to rotate and agitate bacteria 34 for two minutes. The agitation may be executed by applying super-sonic wave or repeating to draw and discharge by the pipette device. In this case, agitation of the distributed suspension, namely the culture medium 30 is performed at angular velocity of 200–300 rpm and amplitude of 2 mm.
At step S 6 , the magnetic particles 33 are distributed by the pipette tip P. Here, DYNA Beads: M-450/CD3 (a brand name) (4×10 8 beads/ml) is used. About this particles of 10 5 /ml are poured into. In this case, magnetic particles of 10 3 /sphere are contained per a carrier. As the diameter of the magnetic particles is about 500 Å–1000 Å and the size of holes of C.C. is about 10 μm, the quantity of magnetic particles is large enough to make the magnetic particles execute orientation and receive the influence of magnetic field.
At this stage, a mixer is driven for two minutes in order to blend the bacteria 34 . The agitation may be executed by applying super-sonic wave. In the case of the mixer, the culture medium 30 that is a suspended liquid distributed, is agitated by oscillation of angular velocity of 200–300 rpm and amplitude of 2 mm, for two minutes. The magnetic particles are distributed after that the bacteria 34 are poured into at step S 6 . Because, the magnetic particles are apt to stick to carriers, and bacteria 34 can be desired to be held in carriers as much as possible. Further, because the magnetic particles should not much influence bacteria and the magnetic particles are only used for collecting bacteria.
By the agitation, the carriers, C.C. 31 encounter magnetic particles 33 and bacteria 34 which are target substances, and the carrier holding micro-substances are constructed by fixing or absorbing.
At step S 7 a , the incubation is continued. Before long, the liquid culture medium 30 that is a suspended liquid, becomes more red.
At step S 7 b , the magnetic field is applied to the separation region 23 a in the liquid passing portion 23 by bringing the magnet 24 close to the liquid passing portion 23 of the pipette tip P. In order to attract the C.C. 31 holding the magnetic particles 33 and bacteria 34 by the magnet 24 , three times of pumping are executed so as to pass the liquid through separation region 23 a.
At step S 7 b - 1 , extracting the coloring matter and cleaning are executed by acetone of 80%. In this case, the coloring matter which is insoluble to water can be extracted by dissolving in acetone and three times of pumping, while the magnet 24 is close to the liquid passing portion 23 . Besides, when the T.T.C. that is soluble in water, is used, the coloring matter can be extracted not by acetone, but by cleaning.
At step S 7 b - 2 , the degree of transmission T % is measured by irradiating the ray with 550 nm wavelength into the extracted liquid.
At step S 8 , the increase in the quantity of bacteria is detected for each concentration of antibiotics. The minimum concentration at which the increase in the quantity of the bacteria is not observed, is the threshold of concentration which can inhibit the increase of the bacteria. The quantity of bacteria at the early state, can be measured by detecting the threshold. Conversely, this method can specify a kind, a concentration, and an antibacterial effect of antibiotics that are effective for bacteria.
The other example of the embodiment is described. In this example, instead of said T.T.C. of marker substance, fluorescence is adhered to the bacteria. The minimum concentration for inhibiting the increase in the quantity of bacteria may be detected by direct measurement of number of the bacteria. This measurement is performed by observing the excited light whose wavelength is different from a predetermined wavelength of incidence irradiated to the bacteria adhered by fluorescence. In this case, measurement can be performed rapidly.
Furthermore, chemical luminescent substances used as a marker substance may be adhered to the captured bacteria, instead of fluorescence. In this case, chemical luminescence (acridinium) can be measured without irradiating light, by using aqueous solution of hydrogen peroxide.
The micro-substances are not limited to the bacteria or viruses, and the marker substances are not always necessary, in the above-mentioned examples. Further, the suspended systems are not always limited to the above-mentioned liquid. Also, each quantity and number is not limited to the above-described case. The carrier is not limited to the above-mentioned C.C.
The present embodiment can easily and rapidly execute the automatic performance of inspection for effective concentration of antibiotics, as easy and rapid inspection is possible by adhering and holding the bio-active-substances (antibiotics and so on) and assay-test-micro-organisms (assay-test-micro-organisms for antibiotics: colon bacilli and so on) and cultivating.
Next, the second embodiment is described.
The present embodiment shows the case of extracting DNA or/and RNA from bacteria, for example. The present embodiment comprises steps S 1 –S 6 except step S 5 for cultivating bacteria and so on, step S 6 for distributing and agitating the magnetic particles, and step S 7 b for capturing the carriers, in such a manner as the first embodiment.
The steps of the present embodiment thereafter are different from the first embodiment. At the step S 7 b - 1 of the present embodiment, the protein bonded to DNA is denatured by SDS or proteinase K so as to facilitate to resolve. Thereafter, DNA is dissolved and extracted by three times pumping and cleaning in the phenol solution. After adding EtBr (Ethidium Bromide), the extracted DNA is irradiated by ultra-violet ray, and DNA or RNA can be detected by receiving fluorescence. Also, DNA can be detected by observing fluorescence by Fluoro-Flow method. Furthermore, chemiluminescence method can be used. DNA can be detected or extracted by using a single strand of DNA as probe, whose base sequence is known, hybridizing complementarily, and forming a double helix.
The third embodiment is described below.
The third embodiment uses a carrier which is formed to be a ball made of cellulose (for example, cellulose acetate) having about 150 μm diameter. The ball having a plurality of cavities or holes of about 10 μm in the surface thereof is used. Also, the magnetic particles having about 1 μm diameter are used as a remote-acting body. The C.C. of about 1000/ml and the magnetic particles are suspended in a liquid that includes kanamycin of about 1 g/ml used as micro-substances. Thereafter, a suspended liquid is generated by agitation with mixer or applying super-sonic wave. This suspended liquid is drawn into the pipette as mentioned above. On the occasion of drawing the liquid, the magnetic field is applied by the magnet used as a magnetic source, brought close to the liquid passing portion.
The cellulose spheres holding magnetic particles are attracted and settled. The supernatant liquid is abandoned, and then a physiological salt solution is poured in, to generate the suspended liquid again.
At the next step, said suspended liquid including cellulose spheres holding magnetic particles and kanamycin is injected to a vein of a tail of mouse. Then the magnetic particles held in carriers can be attracted, transferred, and collected to the root part of the tail by approaching a magnet thereto.
As transfer and orientation of the carrier holding the specified substances and magnetic particles can be performed in human beings and animals, this method can be used for collecting the medicine at the point of disease in order to treat such disease as infection and so on, and can avoid the secondary effect (an effect at different places from the point) (Drug Delivery System; DDS). Also, a cancer can effectively be treated by transferring and collecting the carriers holding antitumor-agent (such as Cis-Platin and so on) with a magnet.
The fourth embodiment is explained on the basis of flow chart of FIG. 4 . The present embodiment shows an example that the carrier holding the magnetic particles, micro-substances including a target substance of the assay etc. is applied to the immunoassay. Said sample distributor of FIG. 2 , and, pipette or disposable pipette tip attached to the distributor, are used for the control of this embodiment.
In this case, as shown in FIG. 4 , the container is formed to be cassette-like. The container has plural vessels, in which samples or reagents necessary for reaction or processing are distributed beforehand. The liquid passing portion having the separation region of the pipette tip P attached to a nozzle of liquid suction line having at least one nozzle, is formed so as to be capable of transferring the carriers holding magnetic particles maintained on the inner wall thereof. The cassette-like container may have one row of the vessels or micro-plate-like plural rows. In the case of micro-plate, the liquid suction line can be arranged so as to be multi-channel, corresponding to the vessels.
In FIG. 4 , reference mark P shows the pipette tip which distributes a predetermined quantity of a sample which is a target substance, from a parent container accommodating a blood sample and so on (not shown in drawings) to an ample reaction container 51 , and draws or discharges insoluble magnetic particles suspended liquid 53 , a cleaning liquid 55 , a marker liquid 56 , a substrate liquid 57 , a cellulose carriers (C.C.) suspended liquid 58 and so on,
Here, the carrier holding magnetic particles means the carrier holding magnetic particles, micro-substances including a target substance of the assay etc. in the surface thereof.
Also, the sample reaction container 51 has plural vessels 51 A– 51 I arranged to be column-like, in a series, loop-like, or zigzag-like. In vessel 51 A, the sample is roughly distributed beforehand. In vessel 51 B, the cellulose-carriers suspended liquid 58 is accommodated beforehand. In vessel 51 C, a predetermined quantity of the insoluble magnetic particles suspended liquid 53 is accommodated beforehand. In vessels 51 D and 51 E, a predetermined quantity of the cleaning liquid 55 is accommodated beforehand. In vessel 51 F, a predetermined quantity of the marker liquid 56 is accommodated beforehand. In vessels 51 G and 51 h , a predetermined quantity of the cleaning liquid 55 is accommodated beforehand. Furthermore, in vessel 51 I, the substrate liquid 57 is distributed, and the vessel 51 I is constructed so as to be able to measure the luminescence.
Further, in the case of assay of CLIA and CLEIA, the sample reaction container 51 is made of opaque materials that do not give the influence of luminescence one another. In the case of assay of EIA, at least the bottom of the container 51 is made of transparent material.
When the immunoassy is executed by using said sample reaction containers 51 and the pipette tip P, at step S 11 , the predetermined quantity of the sample which is distributed to vessel 51 A roughly, is drawn into the pipette tip P to quantitatize.
At step S 12 , the pipette tip P which draws this sample is transferred in order to discharge the entire quantity of the sample drawn into the vessel 51 B accommodating the C.C. suspended liquid 58 . Thereafter, the mixture of the sample liquid and the C.C. suspended liquid is repeatedly drawn and discharged and the entire or predetermined quantity of suspended liquid is drawn into the pipette tip P.
At step S 13 , the entire suspended liquid drawn in the pipette tip P is transferred and discharged into the vessel 51 C accommodating the magnetic particles suspended liquid 53 . Thereafter, the mixture of the sample, the C.C. and the insoluble magnetic particles are repeatedly drawn and discharged to generate the uniformly agitated mixture of the sample, C.C. and the magnetic particles.
Thus, samples and magnetic substance 53 are held in the surface of the C.C.. After elapse of time required, the entire or predetermined quantity of the incubated mixture incubated are drawn in the pipette tip P. Then, the carriers 52 holding the magnetic substances and samples suspended in the mixture are attracted on the inner wall of the liquid passing portion 23 by the magnetic force of the magnet 24 fitted outside of the pipette tip P. Also, a lower level of the drawn liquid is controlled to be near or higher than the lowest part of the magnet 24 , in order to be capable of arresting whole the carriers holding the magnetic substances.
Here, the strength of the magnetic field of the magnet should fall within the range that the carriers holding magnetic substances can be attracted and maintained and can be released by two or three times of repeats of drawing and discharging. The strength of the magnetic field is determined by the position of the magnet, diameter of the liquid passing portion 23 , a kind of the suspension liquid, and, size, mass, and materials and so on of the carrier and so on. Thus, after that the carriers 52 holding magnetic substances 53 are collected again, the mixture excluding the carriers 52 holding magnetic substances, is discharged into the vessel 51 C to be eliminated, and only the carrier holding magnetic substances remains in the pipette tip P. Then, as the carriers holding magnetic substances are wet, the carriers are arrested and maintained on the inner wall of the liquid after the mixture is discharged. Therefore, even if the pipette tip P is transferred, the carriers do not fall off easily.
Next, at step S 14 , the pipette tip P is transferred to the next vessel 51 D together with the carriers 52 being collected, and draws the cleaning liquid 55 in the vessel 51 D. In this case, the magnet 24 is moved away from the pipette tip P, and carriers 52 are released from the arrested state.
Then the carriers 52 holding magnetic substances can effectively be cleaned by drawing and discharging the cleaning liquid 55 . After completion of drawing and discharging the liquid 55 , the entire cleaning liquid 55 in vessel 51 D is slowly drawn into the pipette tip P. Then the magnet 24 is brought close to the pipette tip P again, and collects whole the carriers holding magnetic substances 53 suspended in the drawn cleaning liquid 5 . The cleaning liquid 55 excluding the carriers 52 holding magnetic substances are discharged into vessel 51 D and eliminated, and only carriers 52 remain in said pipette tip P.
At step S 15 , said pipette tip P is transferred to the next vessel 51 E together with the collected carriers 52 . Then, the cleaning liquid 55 in vessel 51 E is drawn, and the cleaning work and collecting work are executed in such a manner that executed in vessel 51 D.
At step S 16 , said pipette tip P attracted by carrier 52 is transferred to the next vessel 51 F. The marker liquid 56 in the vessel 51 F is drawn into the pipette tip P.
Then the magnet 24 is brought away from the pipette tip P, and releases the carriers 52 holding magnetic substances from the arrested state. Consequently, reaction between the carriers 52 holding magnetic substances and the marker liquid 56 can be executed uniformly.
Then, at step S 17 , after completing to drawing and discharging, the liquid is incubated for a required time. Thereafter, the entire marker liquid 56 in vessel 51 F is slowly drawn. Then, the magnet 24 is brought close to the pipette tip P again, and whole the carriers suspended in the drawn marker liquid 56 are arrested. The marker liquid 56 except the carriers 52 are discharged into vessel 51 F and is eliminated, and only the carriers remain in the pipette tip P.
Thereafter, at step S 18 , the above pipette tip P in which the carriers holding magnetic substances are collected, is transferred to the next vessel 51 G. The cleaning liquid in vessel 51 G is drawn into the pipette tip P. After cleaning and collecting carriers 52 holding magnetic substances in such a manner that is executed in vessel 51 D, 51 E, the cleaning liquid 55 in vessel 51 H is drawn, in such a manner that is executed in vessel 51 G, and the carriers 52 holding magnetic substances are cleaned and collected.
Thereafter, at step S 19 , the pipette tip P is transferred to the vessel 51 I. In the case of a method such as assay of CLEIA, that continues luminescence after mixing with the substrate liquid and needs a fixed time for stabilizing the quantity of luminescence. The pipette tip P draws the substrate liquid 57 accommodated beforehand in vessel 51 I. Then, the magnet 24 moves apart from the pipette tip P, and the carriers 52 holding magnetic substances are released from the collected state. Therefore, reaction between whole the carriers 52 holding magnetic substances and the substrate liquid 57 can be uniformly executed by drawing and discharging the substrate liquid 57 .
Then, after completion of drawing and discharging and incubation for a required time, the quantity of luminescence is measured by an optical measuring unit.
The present embodiment can apply to the other method of assay.
For example, the present embodiment can apply to EIA method and so on.
Also, the present embodiment can apply to such a method of assay or an apparatus for clinical inspection that uses immune substances, biological substances or molecular substances such as antigen, antibody, protein, enzyme, DNA, vector-DNA, m-RNA or plasmid, or, marker substance necessary for determining the quantity or property such as isotope, enzyme, chemiluminescence, fluo-luminescence, electro-chemical-luminescence.
Furthermore, for example, the present embodiment can apply to immunoassay, inspection for chemical reaction, or, the unit for extraction, recovery, or isolation of DNA and so on.
The present embodiment can safely (without cross-contamination) and easily execute multi-stage chemical reactions by transferring between reaction containers one by one.
The fifth embodiment is described below.
The present embodiment is the one which uses the carriers holding the dielectric bodies used as remote-acting bodies, having dielectricity being higher or lower than that of liquid, micro-substances or the carriers, instead of magnetic particles.
For example, it is well known that there is alumina, silicon gum, or acetone etc. as substances having high specific dielectricity. Further, there is ferro-electricity. Electric field generated between electrodes mounted outside of the container, are applied to the substances, in order to manipulate the carriers remotely by using dielectric substances or charged substances,.
Usually, in the case of supplying big voltage between electrodes, alternating high-frequency wave of electric field can be applied in order to avoid the generation of reaction between electrodes (electrolysis). Thus, the carrier holding the dielectric substances and micro-substances can be moved by using the interaction between the alternating electric field and electro-dipole induced in the objection,.
In this case, if one of electrodes is formed to be sharp, carriers holding micro-substance can be transferred toward this electrode, because the electric field of electrode formed to be sharp is stronger than the other electrode. Also, if the polarity of voltage supplied to the electrodes reverses, the direction of polarization induced in carriers holding micro-substances is revered. Therefore, the direction of power on the carriers does not vary by the reversing, and the electrophoresis is possible. The polarity induced is changed according to whether the dielectricity of dielectric substances used as a remote-acting body is lower or higher. In the case of the lower dielectricity, as the power directing the carriers to the electrode having weak electric field is stronger than the other electrode, the carriers can move in reverse direction to the above case. The size of holes of the carrier is large enough to perform the orientation of the magnetic particles.
In the case of utilizing electric field in the suspended liquid, the electric conductivity of the solution should be lower to a certain extent, to avoid excess Joule's heat. Furthermore, the present embodiment is capable of controlling plural pairs of electrodes as well as a pair of electrodes, synchronously so as to execute the complicated movement such as rotation.
The sixth embodiment is described below.
The present embodiment is the one that carriers hold both charged substances and magnetic substances used as remote-acting bodies. The present embodiment can control complicated movement such as transferring, rotation, or stationary by applying electric field and/or magnetic field.
Oscillating or rotating the remote-acting bodies by applying or oscillating the magnetic field by solenoid used as a remote-manipulating means, or by movement of charged substances such as synchrotron movement, can remove the remote-acting bodies from the carriers, make the remote-acting bodies hold in the carriers, or agitate the carriers.
The seventh embodiment is described below.
The present embodiment can trap the remote-acting bodies such as high molecular micro-particles suspended in liquid so as to be sandwiched between two opposite rays of laser. Furthermore, the present embodiment can generate a change of the momentum of light between before and after the incidence by irradiation to the transparent bodies, remote-acting bodies, having refractive index different from the surrounding medium.
The change of the momentum is given to the micro particles according to the law of conservation of momentum. As a result, radiation pressure is generated. In the case when the refractive index of the micro-particles is higher than surrounding medium, these total powers face the direction of the focal points of laser, and restrain Brownian motion, and can trap the micro-particles in the position balanced with the external force such as gravity.
The trapped micro-particles follow the movement of the focal points of the laser. Thus, the present embodiment can execute observation and so on with respect to a single micro-particle, by trapping the micro-particles at the focal points of the optical unit. Furthermore, various movements are possible by making the carriers hold magnetic particles and so on.
The eighth embodiment is described below.
As the present embodiment, it is explained that the substance having a higher expansion coefficient than the surrounding suspended liquid is used in the carrier. When the substance is used, the carriers can rise by raising temperature, and can fall by lowering temperature. Such substance is for example, body having a gas wrapped by elastic film. Also, the same control is possible by irradiating the light such as laser and so on to the opaque substances.
Besides, in the above-mentioned description, only the case when the carrier is C.C. is shown. But, the present invention is not limited to the case. Furthermore, as the magnetic source, the electromagnetic or superconducting electromagnet as well as magnet can be used. Furthermore, the carrier can hold two or more kinds of substances used as remote-acting bodies and be controlled by two or more remote-acting means. | Carriers hold remote-acting bodies which can be manipulated by a remote force, and also hold a micro-substance which is a target substance of an assay. The remote-acting bodies are manipulated in order to control the positions of the micro-substances, so as to execute assays for various target substances efficiently, at low cost, easily, and reliably. Various aspects of interest include the carriers which hold the micro-substances, a system suspending the carriers, an apparatus for manipulating the carriers, and a method of controlling the position of the carriers. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to chains, including but not limited to those used to transmit torque between sprocket wheels, and more particularly to an adjustable segmented chain, having a plurality of substantially similar modular links, or pairs of links, capable of interconnecting to form a closed loop chain, such as is commonly used to transmit pedal or motor generated power to one or more drive axles, wheels, or accessories in bicycles, motorcycles, pedal boats, automobiles, household appliances (such as washing machines and driers), and in industrial, military, space, and extreme environment applications. The chain of the present invention may also have applications as a tow chain, as an anchor chain, as a chain used for jewelry bracelets and necklaces, for strap handles of suitcases or purses, as clothing belts, etc.
2. Description of Related Art
Chains are commonly used to transmit torque between rotating devices: for example, bicycle chains transmit torque between sprocket wheels. Conventional bicycle chains, as have been used for one hundred years, consist of a closed oval or circular loop made of a plurality of multi-pan metal modules or links, narrow links alternating and hinged together with wide ones, each link being fitted at its interior to receive the teeth of sprocket wheels, and each link interleaving end-to-end with its adjoining neighbor, joined together by a shared metal pin set perpendicular to the length of the joined links and which pin acts as a fulcrum or axle allowing pivoting between each of the chain's pairs of links to occur substantially in one single plane around that axle. The chains for bicycles which use a derailleur shifting arrangement must allow adjoining links to pivot two directions to accommodate primary and reverse curves (around the derailleur) in one plane; also, for the chain to be derailed from one sprocket wheel to another in the same concentric cluster, a certain small amount of lateral slip or pivot is allowed to occur at the pivoting connection between chain links.
Chains must provide tensile strength to withstand and transmit torque. The perpendicular structure of each link which meshes with the teeth of sprocket wheels must provide both impact and tensile strength. In addition, chain links must pivot with respect to one another to permit the chain to conform and bend either direction in one plane around sprocket wheels without excessive friction and wear. To provide the required strength, conventional chains are made of metal. To permit pivoting, the links of conventional chains are hinged with and connected by metal pins which function as axles, relative to which are attached and turn the two separated side pieces of one module before and those of another behind.
Like the spacing of their sidewalls, conventional chain links are alternatively wide and narrow. The pin is riveted or splayed at each end to sandwich, and prevent the escape of various skewered metal parts: e.g. a more widely spaced side piece from the left module but which extends some distance above, below and beyond the pin connection; then, rubbing against it, a side piece from the right module and its extension; then a wide washer; then the other side piece from the right module, including its extensions; then the other side piece from the (more wide-sided) left module, including extensions; then the rivet or splayed other end of the pin. The spacing "washer" at the middle of each such pin sandwich holds the left and right sidewalls of each module separate from each other to permit entry of sprocket teeth but allows friction to occur between the two left sides of adjoining modules and the two corresponding fight sides. There is friction also between the washer ends and the module sidewalls which touch it, and between the pin and all the components it penetrates. By its bulk this washer also protects the modules' interconnecting metal hinge pins from the wear they would experience if they were struck repeatedly and directly by the teeth as sprocket wheel and chain engaged or if the pedal or motor power applied between sprocket tooth and chain were carried directly by and to the narrow pin in contact with the working edges of sprocket wheel teeth across the direction of their work. Lubricants such as oil typically are used to reduce friction at the points where module side walls and washers turn against one another, the teeth, and pins.
Conventional chain designs, as described above and in common use to transmit power to bicycle drive wheels, have changed little for decades. U.S. Pat. No. 1,130,582 J. M. Dodge, Mar. 2, 1915, is not fundamentally different from the more recent patents reviewed, which reflect mere modifications and improvements. For example, U.S. Pat. No. 4,596,539 K. Yamasaki, May 7, 1985, to facilitate the chain being derailed from one sprocket wheel to another, introduces cutouts or hollows on the inward-facing marginal edges of the wider links. U.S. Pat. No. 4,960,403 M. Nagano, Jul. 28, 1989, proposes deforming the metal of the wider links outward to accomplish the same purpose. U.S. Pat. No. 5,226,857 T. Ono, May 13, 1992, blends the improvements of the Yamasaki and Nagano patents and asserts that the metal deformation and hollowing need occur on one side of the chain only, since the shifting problem noted is significant primarily when the chain goes from a smaller to a larger sprocket wheel (and not vice versa) and since a bicycle's rear sprocket cluster typically has more narrowly spaced and more stages than does its front sprocket cluster.
U.S. Pat. No. 5,288,278 M. Nagano, Dec. 30, 1991, modifies the standard bicycle chain link by adding a flexion limiting device intended to prevent chain tangling during bumpy mountain bike rides. This patent too is limited to conventional chains which employ alternating narrower and wider links rotatably coupled by pins.
All of the conventional chains reviewed tend to be made of steel or other metal. They tend not to slip against the wheels they turn, as belts may against smooth pulleys, because they make a strong mechanical connection, link against sprocket, perpendicular to the direction of chain movement. However, chains so designed have several drawbacks, the relative importance of which in the bicycle application are roughly as follows: (1) they are relative heavy; (2) they rust; (3) they consist of multiple pans; (4) they are complex to manufacture, (5) they present much surface area to dirt and contamination; (6) they require repeated applications of messy, dirt-collecting oil for lubrication; (7) they are hindered by friction between links during rotation; (8) they wear out and/or stretch; (9) they are noisy; and (10) they can be difficult to install and replace.
As a result of the foregoing drawbacks, conventional chains tend to be used only in applications where power transmission is paramount, giving way to belts in other applications. In addition, conventional chains leave something to be desired, at least for certain applications, in other respects. (11) Their high mass and inertia make them somewhat difficult to accelerate and decelerate. (12) They are not particularly aerodynamic. (13) They are wider than is strictly functional, due to their alternatingly wide and narrow sidewalls. (14) They require a specially designed link pin where breakage, if any, tends to occur. (15) Like a baseball bat they are inflexible, and thus they cannot store and release power like a golf club. (16) Their length is not easily varied.
The present invention is a different kind of chain, as strong and powerful as needed, yet designed to minimize each of the disfunctionalities associated with conventional type chains. (1) The modules and chain of the present invention are light weight, being formed typically of injection molded plastics the specific gravities of which may be a fraction (often less than one-sixth) that of their conventional metal counterparts. Sprocket clusters too can be made of lightweight plastic once chains are. This further increases the weight savings. The dimensions of the modules also can be reduced to further reduce weight, if appropriate in terms of the balance of other characteristics desired. In the cycling world, light weight is particularly important for racing and hill climbing applications.
(2) Because it is made of plastic the present invention does not rust. Rust is a major problem for the chains of many amateur cyclists.
(3) The present design involves many fewer parts than the conventional one. Each standard module is of one piece only (typically consisting of two injection-molded pieces bonded or otherwise joined to one another during assembly). Some, but not all, embodiments also require a second type of module for closing and unclosing the loop, which again may be formed of only two pieces removably connected. (4) Fewer parts should mean simpler manufacturing and assembly processes. (5) Unibody modules present a minimal surface area to dirt and contamination.
(6) A number of the plastics which could be used, such as nylon with fiberglass, are or can be considered to be, self-lubricating; thus, the use of oil lubricants can be reduced or eliminated, in turn reducing mess and the adhesion of dirt. Anti-static properties can be given the plastic also to minimize dust and dirt collection, and the rotating joint between modules can itself be shaped so that it will tend to expel contaminants. (7) The present design reduces friction, not only by reducing dirt and contaminants. With the present design, unlike the conventional one, there is little or no friction between the sidewalls of different links when they rotate with respect to one another, nor between sidewalls and the "washer" or other bulk surrounding the pin. Thus a reduced surface area bears friction when the links pivot.
(8) Reducing dirt and friction reduces chain wear. The wear and/or stretch associated with the present invention also will depend on the characteristics of the plastics and additives (e.g. carbon fiber or glass) used, with tradeoffs perhaps necessary at this stage in plastics engineering between strength (impact and/or tensile), on the one hand, and optimal weight and lubricity characteristics, on the other. (9) Plastic links are relatively quiet. (10) The chain of the present invention is relatively simple to install and replace. In a preferred embodiment, it requires the use of no tools to assemble and no tools, or a cutting tool only, to disassemble. It is feasible to replace individual links, not just the entire chain. And it is unnecessary to remove the bicycle's wheels to remove or install the chain.
(11) The chain of the present invention has low mass and inertia. Thus a bicycle using it will be relatively easy to pedal. (12) The links of this chain have smooth, rounded edges and are identical to one another in shape and size, not angular and alternatingly wide and narrow like the conventional chain; hence the chain is aerodynamic, and (13) its overall width may be reduced, if desired, thus permitting more tightly clustered, hence more, sprockets. (14) This chain requires no specially designed, breakage-prone link pin, thus it can be engineered without points more liable to break than the others. (15) The present invention can be made of flexible materials, if desired. In conjunction with oval sprocket wheels or the like, such chain flexibility could be useful to store and release pedal power so as to smooth or otherwise optimize the power curve. (16) The present invention permits ready changes in chain length and tension since the number of links to be used is variable and can be modified from time to time with relative ease.
OBJECTS
An object of this invention is to provide an improved bicycle chain which will work on existing conventional bicycles in replacement of a conventional bicycle chain.
Another object of this invention is to provide an improved racing bicycle chain which will work on existing racing bicycles in replacement of existing racing bicycle chains.
Another object of this invention is to provide an improved mountain bicycle chain which will work on existing mountain bicycles in replacement of existing mountain bicycle chains.
Another object of this invention is to provide a light weight bicycle chain, optimally lighter than existing alternatives.
Another object of this invention is to provide a bicycle chain not susceptible to rust.
Another object of this invention is to provide a bicycle chain with relatively few parts.
Another object of this invention is to provide a bicycle chain which is simple to manufacture.
Another object of this invention is to provide a bicycle chain which stays relatively free of dirt and dust contamination.
Another object of this invention is to provide a bicycle chain which requires little or no oil lubrication and thus tends to remain, and to keep its rider and those who service it, clean of messy oil and dirt associated with oil.
Another object of this invention is to provide a bicycle chain the links of which pivot with respect to one another with relatively little friction.
Another object of this invention is to provide a bicycle chain the longevity of which compares favorably to existing alternatives.
Another object of this invention is to provide a bicycle chain which can be built narrower than existing alternatives.
Another object of this invention is to provide a bicycle capable of achieving more, and more subtle, gear changes, as permitted because a narrower chain means that the bicycle's concentric sprocket wheels can be spaced more closely together than is possible given today's relatively unnarrowable multi-part metal bicycle chains.
Another object of this invention is to provide a bicycle chain which is relatively quiet in operation.
Another object of this invention is to provide a bicycle chain which is relatively easy to install and replace.
Another object of this invention is to provide a bicycle chain which has low mass and inertia and is thus relatively easy to pedal and disinclined to tangle regardless of bumpy terrain.
Another object of this invention is to provide a bicycle chain which has improved aerodynamic characteristics.
Another object of this invention is to provide a bicycle chain which requires no specially designed, breakage-prone link pin.
Another object of this invention is to provide a bicycle chain, the links of which can themselves be flexible to store and release pedal power should this be desired to optimize the pedal power curve in certain applications, for example, in conjunction with oval sprocket wheels.
Another object of this invention is to provide a bicycle chain, the length and tension of which may be modified from time to time with relative ease.
An object of this invention is to provide an improved motorcycle chain which will work on existing conventional motorcycles in replacement of a conventional motorcycle chain.
Another object of this invention is to provide a light weight motorcycle chain, optimally lighter than existing alternatives.
Another object of this invention is to provide a motorcycle chain not susceptible to rust.
Another object of this invention is to provide a motorcycle chain with relatively few parts.
Another object of this invention is to provide a motorcycle chain which is simple to manufacture.
Another object of this invention is to provide a motorcycle chain which stays relatively free of dirt and dust contamination.
Another object of this invention is to provide a motorcycle chain which requires little or no oil lubrication and thus tends to remain, and to keep its rider and those who service it, clean of messy oil and dirt associated with oil.
Another object of this invention is to provide a motorcycle chain the links of which pivot with respect to one another with relatively little friction.
Another object of this invention is to provide a motorcycle chain and sprocket system the longevity of which compares favorably to existing alternatives.
Another object of this invention is to provide a motorcycle chain which is relatively quiet in operation.
Another object of this invention is to provide a motorcycle chain which is relatively easy to install and replace.
Another object of this invention is to provide a motorcycle chain which has low mass and inertia.
Another object of this invention is to provide a motorcycle chain which has improved aerodynamic characteristics.
Another object of this invention is to provide a motorcycle chain which requires no specially designed, breakage-prone link pin.
Another object of this invention is to provide a motorcycle chain, the links of which can themselves be flexible should this be desired to optimize the pedal power curve in certain applications, for example, in conjunction with oval sprocket wheels.
Another object of this invention is to provide a motorcycle chain, the length and tension of which may be modified from time to time with relative ease.
Another object is to provide an improved endless type chain with superior durability and useful life due to superior design, the advantages of which include: strength, uniformity, and range of choices of component material; the maximal and equal sizing of all stress-bearing pans of each module so as to avoid weak points; and the confinement movement between surfaces to chain pivot points designed for minimum friction, thereby minimizing deformity, wear and need for lubricants.
Another object is to provide an endless type chain of linked rigid segments of such material and so joined that the joints are, or can be, self-lubricating without need of din-collecting oil.
Another object is to provide an endless type chain of linked rigid segments which may be antistatically treated so that it and they tend to remain dirt-free and relatively free of din-induced friction.
Another object is to provide an endless chain of linked rigid segments which are so joined that the areas where friction occurs at the pivot points between links is relatively enclosed and isolated from contaminating and friction-causing dust and din.
Another object is to provide an endless chain of linked rigid segments which are so joined that centrifugal and other mechanical forces would tend to expel friction-causing dust and dirt from the pivot points between links.
Another object is to provide an endless chain of linked rigid segments which can be simply and inexpensively manufactured, because each of its modules consists of one piece only, such modules also being typically all identical, or of two types only, and capable of being snapped, locked, glued, ultrasonically bonded, or otherwise bonded together.
Another object is to provide an endless chain of linked rigid segments which do not rust.
Another object is to provide an endless chain of linked rigid segments of relatively light-weight material.
Another object is to provide a bicycle or motorcycle chain in color or colors, including varied and vivid colors and rearrangeable patterns of color to appeal to different classes of consumers, to allow differentiation in marketing, and to allow consumers to artistically personalize their own chains.
Another object is to provide a bicycle or motorcycle or other chain in a variety of materials, including materials with varying tensile strengths, impact strengths, hardness, flexibility, lubricity, temperature tolerances, and ultraviolet tolerances to appeal to different classes of consumers and uses and to allow differentiation in marketing.
Another object of this invention is to provide a bicycle or motorcycle chain which appeals to persons who commute to school or work in good clothing and want to stay clean of messy oil and dirt associated with oil.
Another object is to provide an endless chain of linked rigid segments with a minimum of moving parts, as each of its modules consists of one part only (or two joined parts only), and movement occurring between such pans is concentrated at a relatively frictionless area.
Another object of this invention is to provide an endless chain of linked segments which has low mass and inertia and is thus relatively easy to power.
Another object of this invention is to provide an endless chain of linked segments which has low mass and inertia and is thus unlikely to become tangled in use.
Another object of this invention is to provide an endless chain of linked segments which has improved aerodynamic characteristics.
Another object of this invention is to provide an endless chain of linked segments which requires no specially designed, breakage-prone link pin.
Another object of this invention is to provide a chain, the links of which can themselves be flexible to store and release power should this be desired.
Another object of this invention is to provide an endless chain of linked segments, the length and tension of which may be modified from time to time with relative ease.
Another object is to provide a high performance racing bicycle chain which is extra lightweight, requires little or no oil, cleans up easily, does not rust, and which may be utilized with existing racing bicycles without necessarily making adaptations to other parts of the bicycle.
Another object is to provide a chain for mountain bicycles which is extra light-weight, requires little or no oil, cleans up easily, does not rust, and which may be utilized with existing mountain bicycles without necessarily making adaptations to other parts of the bicycle.
Another object is to provide a superior bicycle chain for use with conventional, or similarly styled, bicycle gear sprocket wheels.
Another object is to provide a superior timing-style chain for automotive and other machine timing chain and/or belt applications.
Another object is to provide a superior chain for outer space and other extreme environmental conditions.
Another object is to provide a superior motorcycle chain, modular, oilfree, rustfree, lightweight, durable, easily assembled, easily installed, easily tensioned, and easily changed.
Another object of this invention is to reduce wear to and improve the longevity of bicycle sprocket wheels by minimizing damage done to their teeth by metal chains, especially by metal chains which have become stretched by use.
Another object is to save additional bicycle weight by providing a light weight plastic bicycle sprocket wheel, and cluster of such sprocket wheels, and derailleur gears, to work with the light weight plastic bicycle chain.
Another object is to improve bicycle gear shifting performance and versatility by adding more concentric sprocket wheels closer together within clusters as permitted because the chain's design permits a narrow chain, hence closely spaced sprocket wheels.
Another object is to save additional motorcycle weight by providing a light weight plastic motorcycle sprocket wheel to work with the light weight plastic motorcycle chain.
Another object of this invention is to provide a colorful plastic jewelry chain.
Another object of this invention is to provide a colorful plastic garment belt.
Another object of this invention is to provide a wenchable plastic tow chain.
Another object of this invention is to provide a wenchable no-rust anchor chain for marine applications.
Another object of this invention is to provide an endless type chain which can be conveniently closed into a loop and reopened again for removal and replacement.
Another object of this invention is to provide an endless type chain which for many applications is superior in performance and durability to alternative products presently available.
SUMMARY OF THE INVENTION
The chain of this invention is constructed of plastic modules connected in end to end relationship. It is conceived for use as a drive chain primarily. It is claimed also for jewelry, clothing, towing, anchor, and assorted other applications. Each individual module is without moving parts and has a cavity between its front and rear ends for receiving a tooth of a sprocket wheel. Each pair of adjacent modules has a transverse pin or pins extending from one module into a transverse pin-receiving socket or sockets of the other module so as to form a rotatable joint between the modules. Various means of constructing and joining the modules are disclosed. The plastic sprocket wheel cluster which the plastic chain permits consists of stair-stepped multiple concentric rings of teeth each of which can be wider than a conventional bicycle chain now allows and which together can support each other by means of a common plastic infrastructure. The chain and cluster are light-weight and non-rusting; they can be also self-lubricating and colorful.
In a preferred "male-female" module embodiment, the present invention comprises a series of end-to-end interconnectable, essentially identical modules for constructing a chain for use with sprocket wheels as on various types of bicycles and motorcycles. Each module is made of two or more pieces joined together, generally herein to be called "halves," although they may be unequal in size. Each module as so completed forms a single body portion with no moving parts and which may be substantially rigid or to some extent flexible. The body portion of each module has two opposed interconnecting ends, and it is in the direction of one (or either) of these ends that the modules travel. In the preferred embodiment, one end of each module, which typically will be the front end, is female and contains one or more symmetrically rotatable (e.g. conical or cylindrical) "sockets" or cavities which is or are oriented transversely to the module's front-rear axis. At the opposing, typically rear or trailing, end of each module is a male end which consists of one or more solid cylinders or other such rotatably symmetrical masses ("pins" in the terminology to be used) whose diameter is slightly smaller than is the diameter of the corresponding position of the female end's socket, and such pin or pins likewise is or are oriented sideways in the same plane as the female end's socket.
In another preferred, "double-male, double-female," embodiment, there are alternating modules of two types. Half the modules are "double females" and have sideways female "sockets" at both their leading and trailing ends. The alternating "double male" modules in this embodiment have sideways male "pins" at both their fronts and rears. There is no need that both types of modules be non-unitary. For example, if the "double female" type of module is assembled from two (e.g. upper and lower) pieces, the neighboring "double male" module can be formed of a single piece. Similarly, if the "double male" modules are assembled from two (e.g. left and right) pieces, then the neighboring "double female" modules can be of unitary construction.
To fashion a chain of such modules of either preferred embodiment one assembles the two or more pieces of each divided module by snapping, locking, gluing, bonding, or otherwise assembling them together so that the female end of one assembled module embraces the assembled male end of its neighbor, allowing it perhaps 90 or more degrees of rotation (45 degrees in either direction from straight) in the plane of the hinge so formed. This process is continued until a suitable length chain has been created, then the ends are looped back to become neighbors, and then they are joined together in the same manner. The two-piece modules can be assembled removeably or permanently, though it may be desirable (and necessary in some applications) that at least one module per closed loop chain be assembled in place or non-permanently for ease of installation and removal. The structure of the end-to-end joint so formed between neighboring modules permits rotation between modules in one plane to accommodate the chain's curving travel around sprocket wheels, including travel around reverse curves. In derailleur application, enough lateral slack can be built into this joint to permit the modular chain to be shifted from one sprocket wheel to another parallel sprocket wheel in the same cluster.
There are various patterns into which the identical-looking finished "male-female" modules can be halved or otherwise divided which will permit their pieces to be so rejoined: e.g. (1) upper and lower true halves; (2) upper-rear (or front) one-quarters and other-three-quarter pieces; (3) right and left halves; (4) fight-front (or rear) one-quarters and other-three-quarter pieces; (5) top to bottom across female end bisecting the socket lengthwise; (6) right-left split female ends with upper-lower split male ends; etc. Note is made here that throughout this application the term "half," whether used as a noun or a verb, is to be interpreted to include not only identical halves but also pairs of pans, or the creation of pairs of parts, which are non-identical, asymmetrical, and/or unequal in size. Patterns (1) and (3) will work for "double female" and "double male" modules. Not all of these methods of dividing the module will work for the perhaps special "loop-closer" module needed to close the two ends and make a continuous loop of the modular chain. Of the six numbered examples described, (1), (2), (5) and (6) are forms of standard modules which would work also as loop closers. Of these, (5) is perhaps the least strongly connected and most difficult to assemble. Type (6) is a particularly preferred embodiment since the two halves of each module can be held together by a lock and key design, rather than by glue or bonding, and this permits them to be readily assembled and disassembled. It is this embodiment which is depicted in the first five drawings which follow.
So that the modular chain can turn and be turned by a sprocket wheel there must be, at or near the center of each module's body, a vertical cavity shaped to receive then release a single tooth of a revolving sprocket wheel. Some curve or scoop to the front, back and sides of this cavity opening may be desirable to facilitate reception and release of a sprocket wheel tooth, particularly during shifting or when the teeth are tapered. The vertical cavity should go all the way through the module's body, top to bottom, or there should be both a top and a bottom indentation type of cavity, in applications where, as with typical derailleur-fitted bicycles, the chain must travel reverse curves. The vertical cavity should receive the tooth deeply, and its walls should be steep at least part of the way down, so that the tooth's work edge and the cavity wall make a strong contact perpendicular to the sprocket wheel's radius, the better to transmit torque.
In one preferred embodiment the modules, and half-modules, are each integrally formed of a suitable plastic material, such as a nylon-fiberglass or nylon-carbon fiber mix, or other elastomer or acetal plastic, providing for a very low friction or substantially frictionless rotatable joint between modules. (The tensile strength, impact strength, friction, lubrication, weight, color, and other properties of the plastic can be modified and balanced for various applications by the mix of ingredients and additives used.) In such an embodiment, the rotatable joint can be considered to be self lubricating and is positioned internally to the module where it is not apt to become dirty; also, it can be antistatically treated and shaped to expel dirt.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 generally illustrates a perspective view of two separated, and poised to be joined, identical half modules, or links, of the chain in a preferred key-lock, male-female embodiment. The module is divided so that its barrel, or female end, is split into right-left halves. At the same time, its pin, or male, end is a stepped diameter cylinder, the large-diameter ends of which are split left-right as are the barrel-halves and the smaller diameter extremities of which are divided into generally upper-lower halves, each of which is fitted with an outward-facing key at its unattached extremity. The socket of each barrel half is stepped to correspond to the two differing pin diameters. The socket's narrow diameter mid-section is fitted with one or more channels to permit passage of the keys during assembly, at an angle not encountered in normal use. Once the module is assembled (typically in chain fashion), each key fits into a slot provided in the opposing larger diameter pin half.
FIG. 2 generally illustrates one symmetrical half of a single module, or link, of the chain in a preferred FIG. 1 type embodiment viewed from above.
FIG. 3 generally illustrates one symmetrical half of a single module, or link, of the chain in a preferred FIG. 1 type embodiment viewed from the side.
FIG. 4 generally illustrates one symmetrical half of a single module, or link, of the chain in a preferred FIG. 1 type embodiment viewed from the female end.
FIG. 5 illustrates from an angle two FIG. 1 type modules of the chain. The two halves of one are pressed together. At right angle assembly position with respect to the first, the second module's two halves are shown as yet separate but poised to be slipped past one another through the key and inside the socket of the first so that the inward planar surfaces of the second module's split cylinder male ends will lie together within and through the two adjoining half-barrels of the first module while the outward-facing keys of the second module's split cylinder male ends will fit into notches provided in the wider-diameter portion of the opposing pin half.
FIG. 6 generally illustrates a single half-module, or link, of the chain in a preferred male-female embodiment viewed from one side where the module is divided into two symmetrical halves, a true upper half and a true lower half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together and where, for illustration, the pin is given a narrow-waisted double truncated cone shape.
FIG. 7 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 6 type embodiment viewed from above.
FIG. 8 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 6 type embodiment viewed from the female end.
FIG. 9 generally illustrates a single half-module, or link, of the chain in a preferred male-female embodiment viewed from one side where the module is divided into two symmetrical halves, a true left and a true right half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together and where, for illustration, a variant straight cylindrical shape is given the pin and socket.
FIG. 10 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 9 type embodiment viewed from above.
FIG. 11 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 9 type embodiment viewed from the female end.
FIG. 12 illustrates generally illustrates a side view of a completed loop of rotatably joined FIG. 1 type "male-female" modules, forming an endless chain, and set to turn around and be turned by a plurality of toothed sprocket wheels (as in a derailleur bicycle application, thus illustrating, by the reverse curve, use of what might ordinarily be thought of as the chain's reverse side). Also illustrated is a cluster of multi-stage concentric sprocket rings (not necessarily circular) fashioned of a light weight plastic and positioned on a plastic cone or series of wheels.
FIG. 13 generally illustrates an end view of a completed loop of rotatably joined FIG. 1 type "male-female" modules, forming an endless chain, and set to turn around and be turned by a one sprocket ring of a multi-stage sprocket ring cluster. Also illustrated is a multi-stage set of concentric sprocket tings fashioned of a light weight plastic, the teeth of which are, or may be, somewhat wider than are those of conventional clustered metal sprocket wheels.
FIG. 14 generally illustrates a top view of another type of variant single module, or link, of the chain in a preferred split-pin embodiment (where the line of division between the unitary module's two joined halves or pans is not shown).
FIG. 15 generally illustrates an angle view of a "double female" type module disassembled into upper and lower halves.
FIG. 16 generally illustrates an angle view of a single piece "double male" type module, designed for use in alternation with the FIG. 15 type module.
EIG. 17 generally illustrates an angle view of a "double female" type module manufactured in one single piece.
FIG. 18 generally illustrates an angle view of a "double male" type module which is split into right/and left halves and is designed for use in alternation with the FIG. 17 type module.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 generally illustrates a perspective view of two separated, and poised to be joined, identical half modules, or links, of the chain in a preferred key-lock, male-female embodiment. The module is divided so that its barrel, or female end, is split into right-left halves. At the same time, its pin, or male, end is a stepped diameter cylinder, the large-diameter ends of which are split left-right as are the barrel-halves and the smaller diameter extremities of which are divided into generally upper-lower halves, each of which is fitted with an outward-facing key at its unattached extremity. The socket of each barrel half is stepped to correspond to the two differing pin diameters. The socket's narrow diameter mid-section is fitted with one or more channels to permit passage of the keys during assembly, at an angle not encountered in normal use. Once the module is assembled (typically in chain fashion), each key fits into a slot provided in the opposing larger diameter pin half.
Plastic composition permits the module to be lightweight, integrally molded for strength and simplicity, and, to some degree, self-lubricating. Rigidity, or at least the ability to resume prior dimension after stretching or flexing, is required to the extent that the chain will not permanently stretch and cease to fit the sprocket wheels for which it is designed. Different facets of the module are identified as follows: "1" is the narrow diameter portion of the pin; "2" is the wide diameter portion of the pin; "3" is the key; "4" are the sidewalls; "5" is the scoop in the interior sidewall; "6" is the barrel; "7" is the narrow diameter portion of the socket within the barrel; "8" is the wide diameter portion of the socket within the barrel; "9" is the keyhole; "10" is the lock; "11" is the mold-assist; and "12" is the sprocket-holder.
The module is halved or otherwise divided so that it can be reassembled with another similar module interconnectedly end-to-end, the pin of one module inside the barrel of its neighbor. See FIG. 5.
The pin end, "1/2/3," may be considered the rear of the module, as the chain will perform and wear best if the chain is oriented with this pin end traveling last and horizontal, as it passes over the top of a vertically oriented sprocket wheel.
The bearing surfaces of the pin, "2," and socket, "8," which meet one another must be very smooth to minimize friction and should fit one another loosely enough to permit rotation, tightly enough to prevent undue slack. To achieve such smoothness requires well polished molds and care. The pin must be strong to withstand stress, especially shearing stress (and some twisting stress during gear shifts) where narrow pin "1" joins wider pin "2," where "2" joins the sidewall "4," and where key "3" joins lock "10." Rounded comers and integral formation, as by injection molded plastic, will lend strength to these connecting areas of the module.
The dual diameter pin design shown in this Figure is strong at the pin's sidewall connections because its diameter is greatest there. Also, this pin design will cause the pin to be self-centering within the socket of its neighbor's barrel and thus reduce or eliminate friction between one module's interior sidewall "4" and the exterior wall of the neighboring module's barrel "6." In addition this pin design permits the barrel, "6," and the connection between its two halves, to be most massive and strong toward the pin's center, where it takes the greatest beating from and does most of its work against the teeth of sprocket wheels.
The two parallel sidewalls, "4," are integrally formed with and connected strongly at their rear end to the perpendicularly set pin, "1/2," and at their other end to a larger perpendicular barrel, "6," here shaped like a larger cylinder through which extends a void, or socket, "7/8," shaped to fit the pin, here like a dual diameter cylinder, thinnest at the center, and set perpendicularly to the sidewalls like the pin which it parallels, and sized to a diameter, along each point of its length, just slightly larger than that of the pin, "1/2," which forms the body's other end. The interiors of the parallel sidewalls, "4," are shown bevelled with a scoop, "5," to facilitate the receipt of the sprocket teeth by the sprocket holding cavity, "12," important particularly during lateral gear changes. The width of the sidewalls, "4," can be as narrow (and hence lightweight) as the strength of the plastic used will allow. The sidewalls, "4," must be fashioned narrow enough so that when the chain formed by these modules is in use on one of the smaller sprocket wheels within a cluster its exterior sidewall will not contact and be interfered with by an adjoining larger sprocket wheel.
The barrel, "6," is shown cylindrical in exterior aspect. This shape best accommodates the teeth of most bicycle and motorcycle sprocket wheels, easing the tooth's entrance and holding it secure once well inserted. The exterior walls of the barrel must be of strong material and design to stand up over time against repetitive entry hits from sprocket teeth and to transmit force from sprocket to chain to sprocket. The barrel walls cannot compress unduly under such forces for otherwise they would pinch the pin, "1/2," contained in the barrel's socket, "7/8," causing an unacceptable amount off fiction at the rotating joint between modules.
The pin/socket joint ("1/7 and 2/8" ) must rotate with a minimum of friction, optimally assisted by self-lubricating characteristics of the plastics or other materials used and the ultrasmooth surfaces of the parts in contact. These parts must be strong enough to take the stress of pulling action as well as of rotating between modules, especially at their respective bearing edges where pressure is applied to their contact when the chain is stretched. Also, the barrel-sidewall ("6-4" ) connection must be a strong one; that the two are rounded at contact and integrally injection molded lends strength to this stress point, as does the slight bulking up and rounding of the top and bottom cylinder sidewall joint.
The sprocket-holder, "12," is a generally rectangle-shaped socket or void at the center of the module, extending from bottom of the module (through to its top in the embodiment this Figure illustrates) and fitted to receive one tooth at a time of a sprocket wheel. The cylindrical shape of the barrel exterior makes for a generously sized opening and sloping wall at the sprocket-holder's front and rear and helps it to receive and release sprocket teeth. This shape also provides maximum strength at its center, where the work edges of the seated tooth and the barrel's exterior meet each other at the perpendicular when torque is applied and transmitted between sprocket wheels. Even so, since the sprocket teeth typically have rounded corners, the joint between the sidewall and barrel can be strengthened, if desired, by bulking up and rounding the corners of this joint slightly, especially at the otherwise most weakly connected tops and bottoms. In applications where the chain must run through reverse curves, such as with a bicycle derailleur, it is essential that both the top and the bottom of the module have either a separate or a shared sprocket-holder. The rectangular top to bottom hole clear through the module in this Figure is a shared sprocket holder, and will accept sprocket teeth from either sides, working thus for standard and for reverse curves.
In this embodiment, each narrow half-pin, "1," is fitted with an outward-facing key, "3," at or near its unattached extremity. No glue or permanent bonding is required in this embodiment of the invention because the module halves are held together by the keys, "3," rotated keyholes, "9," and locks "10." The socket of each barrel half is stepped to correspond to the two differing pin diameters, and at the narrow mid-section is fitted with one or more keyhole channels "9" to permit passage of the keys during assembly, at an angle not encountered in normal use. Once the module is assembled (at right angles to its neighbor) in chain fashion, one module's socket embracing its neighbor's pin, each key fits into a slot or lock provided in its opposite halls larger diameter pin, and its withdrawal is impeded by "7," the narrow diameter portion of the neighboring module's socket, when the links are positioned in normal use.
Two features shown in this Figure, the two-sided keyhole, "9," and the mold-assist, "11," are inessential to the chain's function but merely facilitate manufacturing economies. A single sided keyhole could also be employed, which would further reduce the remote chance of accidental disassembly, since the two keys could not pass simultaneously. The mold-assist is unnecessary if one is willing to have the module pieces be asymmetrical or to use advanced (and more expensive) molding techniques.
FIG. 2 generally illustrates one symmetrical half of a single module, or link, of the chain in a preferred FIG. 1 type embodiment viewed from above. Different facets of the module are identified as follows: "13" is the narrow diameter portion of the pin; "14" is the wide diameter portion of the pin; "15" is the key; "16" are the sidewalls; "17" is the scoop in the interior sidewall; "18" is the barrel; "19" is the narrow diameter portion of the socket within the barrel; 20" is the wide diameter portion of the socket within the barrel; "21" is the keyhole; "22" is the lock; and "23" is the mold-assist.
FIG. 3 generally illustrates one symmetrical half of a single module, or link, of the chain in a preferred FIG. 1 type embodiment viewed from the side. Different facets of the module are identified as follows: "13" is the narrow diameter portion of the pin; "14" is the wide diameter portion of the pin; "15" is the key; "16" are the sidewalls; "17" is the scoop in the interior sidewall; "18" is the barrel; "19" is the narrow diameter portion of the socket within the barrel; 20 is the wide diameter portion of the socket within the barrel; "21" is the keyhole; "22" is the lock; and "23" is the mold-assist.
FIG. 4 generally illustrates one symmetrical half of a single module, or link, of the chain in a preferred FIG. 1 type embodiment viewed from the female end. Different facets of the module are identified as follows: "13" is the narrow diameter portion of the pin; "14" is the wide diameter portion of the pin; "15" is the key; "16" are the sidewalls; "17" is the scoop in the interior sidewall; "18" is the barrel; "19" is the narrow diameter portion of the socket within the barrel; "20" is the wide diameter portion of the socket within the barrel; "21" is the keyhole; "22" is the lock; and "23" is the mold-assist.
FIG. 5 illustrates from an angle two FIG. 1 type modules of the chain. The two halves of one are pressed together. At fight angle assembly position with respect to the first, the second module's two halves are shown as yet separate but poised to be slipped past one another inside the socket of the first so that the inward planar surfaces of the second module's split cylinder male ends will lie together within and through the two adjoining half-barrels of the first module while the outward-facing keys of the second module's split cylinder male ends will fit into notches provided in the wider-diameter portion of the opposing pin half. Different facets of the module are identified as follows: "24" is the narrow diameter portion of the pin; "25" is the wide diameter portion of the pin; "26" is the key; "27" are the sidewalls; "28" is the scoop in the interior sidewall; "29" is the barrel; "30" is the narrow diameter portion of the socket within the barrel; "31" is the wide diameter portion of the socket within the barrel; "32" is the keyhole; "33" is the lock; "34" is the mold-assist; and "35" is the sprocket holder.
The right angle position is necessary to assemble and to disassemble the modules due to the design of the keyhole and lock mechanism. When the chain is placed in normal use such a position between adjoining links is not attained, thus unintended disassembly is prevented.
FIG. 6 generally illustrates a single half-module, or link, of the chain in a preferred male-female embodiment viewed from one side where the module's division is into two symmetrical halves, a true upper half and a true lower half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together and where, for illustration, the pin is given a narrow-waisted double truncated cone shape. Different facets of the module are identified as follows: "36" is the pin; "37" are the sidewalls; "38" are the male and "39" are the female connectors; "40" is the scoop in the interior sidewall; "41" is the barrel; "42" is the socket within the barrel; and "43" is the sprocket holder.
FIG. 7 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 6 type embodiment viewed from above where the module is divided into two symmetrical halves, a true upper half and a true lower half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together. Different facets of the module are identified as follows: "36" is the pin; "37" are the sidewalls; "38" are the male and "39" are the female connectors; "40" is the scoop in the interior sidewall; "41" is the barrel; "42" is the socket within the barrel; and "43" is the sprocket holder.
FIG. 8 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 6 type embodiment viewed from the female end where the module is divided into two symmetrical halves, a true upper half and a true lower half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together. Different facets of the module are identified as follows: "36" is the pin; "37" are the sidewalls; "38" are the male and "39" are the female connectors; "40" is the scoop in the interior sidewall; "41" is the barrel; "42" is the socket within the barrel; and "43" is the sprocket holder.
FIG. 9 generally illustrates a single half-module, or link, of the chain in a preferred male-female embodiment viewed from one side where the module is divided into two symmetrical halves, a true left and a true right half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together and where, for illustration, a variant straight cylindrical shape is given the pin and socket. Different facets of the module are identified as follows: "44" is the pin; "45" are the sidewalls; "46" is the scoop in the interior sidewall; "47" is the barrel; "48" is the socket within the barrel; "49" is the sprocket holder; and "50" are the connectors.
FIG. 10 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 9 type embodiment viewed from above where the module is divided into two symmetrical halves, a true left and a true right, with opposing connectors capable of being snapped, glued or ultrasonically bonded together. Different facets of the module are identified as follows: "44" is the pin; "45" are the sidewalls; "46" is the scoop in the interior sidewall; "47" is the barrel; "48" is the socket within the barrel; "49" is the sprocket holder; and "50" are the connectors.
FIG. 11 generally illustrates a single half-module, or link, of the chain in a preferred FIG. 9 type embodiment viewed from the female end where the module is divided into two symmetrical halves, a true left and a true right half, with opposing connectors capable of being snapped, glued or ultrasonically bonded together. Different facets of the module are identified as follows: "44" is the pin; "45" are the sidewalls; "46" is the scoop in the interior sidewall; "47" is the barrel; "48" is the socket within the barrel; "49" is the sprocket holder; and "50" are the connectors.
FIG. 12 illustrates generally illustrates a side view of a completed loop of rotatably joined FIG. 1 type "male-female" modules, forming an endless chain, and set to turn around and be turned by a plurality of toothed sprocket wheels (as in a derailleur bicycle application, thus illustrating, by the reverse curve, use of what might ordinarily be thought of as the chain's reverse side). Also illustrated is a cluster of multi-stage concentric sprocket tings (not necessarily circular) fashioned of a light weight plastic and positioned on a plastic cone or series of wheels
Different facets of the chain module are identified as follows: "51" is the pin; "52" are the sidewalls; "53" is the barrel; "54" is the socket within the barrel; and "55" is the sprocket holder.
The derailleur reverse curve wheel is "56" and its teeth are "57. " Different facets of the sprocket wheel cluster are identified as follows: "58" is smallest of concentric sprocket wheel ringss; "59" is a somewhat larger sprocket ring; "60" is a medium sized sprocket ring; "61" is a larger sprocket ting; "62" is a large sprocket ring; "63" are the teeth of sprocket ring cluster.
The sprocket holder, "55," is a cavity which goes through from top to bottom of each link of the chain and thus receives equally well the teeth of the derailleur's reverse curve, "56," and the teeth of the cluster, "63."
FIG. 13 illustrates generally illustrates an end view of a completed loop of rotatably joined FIG. 1 type "male-female" modules, forming an endless chain, and set to turn around and be turned by one toothed ting of a multi-stage sprocket ring cluster. Also illustrated is a multi-stage set of concentric sprocket rings fashioned of a light weight plastic, the teeth of which are, or may be, somewhat wider than are those of conventional metal sprocket wheels. These sprocket rings may be circular, oval, or any other closed planar shape.
Different facets of the chain module are identified as follows: "51" is the pin; "52" are the sidewalls; "53" is the barrel; "54" is the socket within the barrel; and "55" is the sprocket holder.
Different facets of the sprocket ring cluster are identified as follows: "58" is smallest of concentric sprocket rings; "59" is a somewhat larger sprocket ring; "60" is a medium sized sprocket ring; "61" is a larger sprocket ring; "62" is a large sprocket wheel; "63" are the sprocket wheel cluster's teeth.
The multi-stage sprocket ring cluster ("58-63") is fashioned of a light weight plastic of similar hardness to that of the plastic modular chain. The toothed rings of the cluster need not be solid stand-alone disks but, to reduce weight, can be mounted together on a cone or other common supporting structure and connected to an axle by spokes or other infrastructure. As shown by the unlabeled straight diagonal lines in this drawing, which represent the edges of an internally braced plastic cone on which the rings are mounted, the rings can and usually would be connected to one another integrally and/or through a common infrastructure. The teeth, "63," of these sprocket rings are, or may be, somewhat wider than are those of conventional metal sprocket wheels. This is done to provide extra strength and durability to the teeth, "63." To do so is possible because all sprocket holding cavities of the chain of the present invention, "55," are equally wide, not alternatingly wide and narrow as in conventional chains.
Alternatively, one could narrow the chain and cluster the sprocket rings more closely together. Such a solution would make sense where the ability to add more gears was of paramount importance and, particularly, where the weight of metal sprocket wheels was acceptable.
FIG. 14 generally illustrates a top view of another type of variant single module, or link, of the chain in a preferred dual or split-pin embodiment (where the line of division between the unitary module's two joined halves or parts is not shown). Different facets of the module are identified as follows: "64" are the pins; "65" are the sidewalls; "66" is the scoop in the interior sidewall; "67" is the barrel; "68" is the socket within the barrel; and "69" is the sprocket holder.
FIG. 15 generally illustrates an angle view of a "double female" type module disassembled into upper and lower halves. Different facets of the chain module are identified as follows: "70" are the sidewalls; "71" is the scoop in the interior sidewall; "72" are the barrels; "73" are the sockets within the barrels; and "74" is the sprocket holder. Connecting fasteners, "75," are shown to snap the two halves of the module together, or to help them remain together once they have been joined mechanically or by glue, ultrasonic bonding, or the like. The "73" socket-side seams of the barrel, "72," are shown beveled back slightly to reduce the change of protrusions which could cause friction between it and a contained neighboring module's male pin to occur in use. This module is for use in alternation with the "double male" module shown in FIG. 16. It makes a good loop closer but may have a tendency to come apart when the chain is under tension.
FIG. 16 generally illustrates an angle view of a "double male" type module designed for use in alternation with the FIG. 15 type module. Different facets of the module are identified as follows: "76" are the pins; "77" are the sidewalls; "78" are the scoops in the interior sidewalls; and "79" is the sprocket holder. This module can be manufactured in one single part. This is advantageous in terms of manufacturing and assembly cost and also in terms of reducing friction which could result from uneven seams where module halves are joined together.
FIG. 17 generally illustrates an angle view of a "double female" type module (alternate to that of FIG. 18) manufactured in one single piece. Different facets of the module are identified as follows: "80" are the sidewalls; "81" is the scoop in the interior sidewall; "82" are the barrels; "83" are the sockets within the barrels; and "84" is the sprocket holder.
FIG. 18 generally illustrates an angle view of a "double male" type module which is split into right and left halves and is designed for use in alternation with the FIG. 17 type module. Different facets of the module are identified as follows: "85" are the pins; "86" are the sidewalls; "87" are the scoops in the interior sidewalls; and "88" is the sprocket holder.
It is to be understood that the above description is intended to be illustrative and not restrictive. The bicycle chain applications are those which have been emphasized in the above specifications but are no means exclusive. Among the many other contemplated applications are included the following: tow chains, jewelry bracelets and necklaces, garment belts, purse straps, valise handles, washing machine and drier belt or chains, automotive drive and timing belts and chains, etc. The scope of the invention should, therefore, be considered not as limited by the above description, but instead with reference to the appended claims, along with the full scope of equivalents to which they are entitled. | The chain is constructed of plastic modules connected in end to end relationship. It is claimed for all chain uses, including but not limited to use as a drive chain. Each individual module is without moving parts and, in most drive chain applications, has a cavity between its front and rear ends for receiving a tooth of a sprocket wheel. Each pair of adjacent modules has a transverse pin or pins extending from one module into a transverse pin-receiving socket or sockets of the other module so as to form a rotatable joint between the modules. Various means of constructing and joining the modules are disclosed. The plastic bicycle sprocket ring cluster which the plastic chain permits consists of stair-stepped multiple concentric rings of teeth which can be wider than a conventional bicycle chain now allows and which together can support each other by means of a common plastic infrastructure. The chain and cluster are light-weight and non-rusting; they can be also self-lubricating and colorful. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates generally to displaying information on a graphic user interface (“GUI”) and more specifically to displaying information in such a way as to quickly and easily communicate information to a user.
DESCRIPTION OF RELATED ART
[0002] Computers and other electronic devices with GUI's are used to communicate information. A part of this communication process involves displaying information on a GUI in an efficient manner. In many retrieval and browsing user interfaces, documents are represented by scaled-down images. For example, if the document contains multiple pages, each page may be represented by a separate icon. If each page of a document is represented by an icon, many icons are needed to display a large document. This approach is generally too cumbersome to use. In an alternative approach, a single icon may be used to represent the entire document. Generally, the first page of the document is arbitrarily chosen to represent the document regardless of whether the visual appearance of the first page provides a visual cue for association with that particular document. It is therefore desirable to have a system to represent documents or other items such that information about a document or item is easily relayed to and understandable by a user.
SUMMARY OF THE INVENTION
[0003] A computer system is disclosed that comprises a display, a processor coupled to the display, and a memory coupled to the processor. Stored in the memory is a routine, which when executed by the processor, causes the processor to generate display data. The routine includes extracting at least one visual feature from a document having a plurality of pages, ranking the pages in the document according to the at least one visual feature, selecting a page for representing a document according to a rank, and displaying the selected page as the display data. Additional features, embodiments, and benefits will be evident in view of the figures and detailed description presented herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The features, aspects, and advantages of the invention will become more thoroughly apparent from the following detailed description, appended claims, and accompanying drawings in which:
[0005] FIG. 1A illustrates thumbnails of all the pages in a document.
[0006] FIG. 1B illustrates the first three pages.
[0007] FIG. 2A illustrates a first row of icons corresponding to the three most visually significant pages of a document;
[0008] FIG. 2B illustrates pages that contain distinctly different visual differences;
[0009] FIG. 3 illustrates a more compact representation of all the pages in a document; and
[0010] FIG. 4 illustrates one embodiment of a computer system.
DETAILED DESCRIPTION OF THE INVENTION
[0011] A method and apparatus for generating and displaying a visual summarization of a document is described. In one embodiment, a technique described herein extracts visual features from the document and ranks multiple pages of a document based upon at least one or more visual features of the page. The pages may be presented on a graphical user interface (GUI) to a user with features being displayed that are ranked higher.
[0012] Some portions of the detailed descriptions which follow are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.
[0013] It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussion, it is appreciated that throughout the description, discussions utilizing terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
[0014] The present invention also relates to apparatus for performing the operations herein. This apparatus may be specially constructed for the required purposes, or it may comprise a general purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CDROMs, and magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.
[0015] The algorithms and displays presented herein are not inherently related to any particular computer or other apparatus. Various general purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform the required method steps. The required structure for a variety of these systems will appear from the description below. In addition, the present invention is not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the invention as described herein.
[0016] A machine-readable medium includes any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer). For example, a machine-readable medium includes read only memory (“ROM”); random access memory (“RAM”); magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.); etc.
[0000] Overview
[0017] Techniques described herein provide a scheme to rank page icons (e.g., thumbnails) according to their visual saliency. The rankings may be used to select certain pages, preferably those with more salient features, for display. This solution may result in increasing the ease of document recall as opposed to display only the first set of pages of a document with reduced sized images to provide a visual clue as to the contents of a document. Additionally, techniques described herein also provide for various effective representations of document content in applications with limited display size.
[0018] FIG. 1A illustrates thumbnails of all the pages in a document. FIG. 1B illustrates the first three pages, arbitrarily chosen, does not help recall the document. By showing pages with the most salient features, as shown in FIG. 2A , or pages with distinctly different visual appearances, as shown in FIG. 2B , a user is provided, generally, with more information to recall a particular document. Utilizing visual saliency and distinctive features, a more compact representation of all pages in a document may be obtained as illustrated in FIG. 3 .
[0019] The representations in FIGS. 2A, 2B , and 3 , and other suitable representations, are possible using a combination of components such as, for example, features that describe visual characteristics of a document image, feature extraction and representation scheme, and a measure of visual saliency. Each of these features are described below.
[0020] A set of features capable of describing the visual characteristics of a document image include textural and layout feature information. Textural features may include one or more of position, size, ink density, line spacing, color and contrast. Layout features may include one or more of configuration of blocks (e.g., column, header, etc.) or types of blocks (e.g., picture, line art, text, etc.). Features that are known to play a significant role in human perception and memory, such as, for example, surrounding space, letter height, bold, bullets, indentation, all capitalization, italics, underlining and other suitable features.
[0021] The features extraction/representation scheme component involves the use of document analysis systems that are capable of segmenting blocks, detecting font sizes within blocks, and extracting other relevant information, such as, for example, the textural and layout features described above. Although visual information is naturally conveyed by a description language, in one embodiment a vector representation is used instead to facilitate applications of various techniques developed for information retrieval.
[0022] The measure of visual saliency may be based upon a variety of factors such as, for example, psychological experiments that provide some guidelines for designing this component. For instance, it has been determined that pictures tend to draw more attention than text blocks and character size is more significant than character style. The presence of attractive features contributes to the total visual saliency of the page. Optionally, this visual saliency component can also be normalized using schemes similar to term weighting for text retrieval to account for features common to all documents in a database.
[0023] Utilizing these components, visual features are first extracted for all pages in a database using methods known in the art. Pages in a document are then ranked according to their visual significance and uniqueness. The user or system designer may determine which visual features are significant or unique. Since the number of different visual features may be quite large, the visual features chosen by a user or a system designer may also be quite large. The ranking serves as the basis for the selection of representing icons in FIG. 2A .
[0024] In addition to ranking pages, visual features may also be used to provide a distance measure between documents. If the visual features are represented in vector form, as is typically done in image-based retrieval techniques, conventional information retrieval techniques as developed for a vector space model may be applied to produce effective iconic document representations. For example, clustering of the pages may reveal distinct page types as shown in FIG. 2B . While clustering of images is commonly performed as a navigation aid to find similar documents, clustering is used within a document having multiple pages. This is analogous to finding “keyframes” in a video.
[0025] Treating pages in a document as frames in a sequence may also lead to compact representations. “Scene changes” can be detected by comparing the visual distance between two consecutive pages to a threshold, by looking for transitions to different page types subsequent to custering as described above, or by other variations such as, for example, combining visual saliency scores. When the distance between consecutive pages is very small, only one of the two needs to be selected. Sequence of visually similar or uninteresting pages may be stacked to reduce space required as illustrated in FIG. 3 . It will be appreciated that these components may be utilized independently or in combination with one another to create other novel usages.
[0000] An Exemplary Algorithm
[0026] The visual summarization system described herein uses a source document as input. In the first phase of the process, a number of, for example, color bitmaps are generated. Each bitmap represents a separate page of the source document. Visual features are then extracted from these bitmaps using document analysis techniques. Two functions Saliency and VisualDist defined over these features enable the effects shown in FIGS. 2A, 2B , 3 .
[0027] The techniques described herein may operate on a variety of document types by using the feature extraction process that is assumed to utilize common commercial optical character recognition (OCR) systems and operates on the most common denominator for document representation: image bitmaps. The bitmap generation process is described for several common document formats, such as, for example, paper documents, postscript, portable document format (PDF), hypertext markup language (HTML) and Word documents. Although it is also possible to develop feature extraction modules designed specifically for each document type, using a common representation simplifies the algorithm description. Generalization to other document media may also be similarly derived.
[0000] Bitmap Generation
[0028] Generating a bitmap can be used for any type of computer-generated source document. However, on occasion it may be more efficient or convenient to use a specific method based on a particular type of source document. The following description provides a general method and several type-specific methods.
[0029] On an operating system (“OS”) such as Microsoft Windows, a printer driver is a software application that translates rendering commands from some controlling application into a printable representation of a document. A user typically has installed one printer driver for each different type of printer in which access is granted.
[0030] Given a source document S generated by application A, the general methodology operates as follows. The user runs application A, loads document S, and selects the “print” function. The user then selects a printer driver that, instead of sending its output to a printer, creates a number of color bitmap images. The document is paginated just as if it was to be printed. The user optionally has control of font sizes and target paper size, depending on the application A.
[0031] Techniques for creating such a printer driver are known in the art since it does not differ significantly from any other printer driver. It is assumed that a bitmap corresponds to a page intended for a printer according to a default dots-per-inch factor. Therefore, an 8.5×11″ page corresponds to, for example, a 612×792 bitmap with a 72 dpi factor.
[0032] In an alternative embodiment, the user selects an existing printer driver that generates Postscript™ output (such drivers are commonly available as part of an OS or through suppliers such as Adobe Inc), and selects the “Print to File” option. In this way, a postscript file can be generated from an arbitrary source document. This postscript file, in turn, can be transformed into a number of bitmap images.
[0033] Tools for using HTML to create bitmap images are known in the art. Such tools are available from Sun such as Hotjava™, Microsoft such as Internet Explorer ActiveX™ control and AOL such as Netscape Mozilla™ project. Such a tool can further use Dynamic HTML, XML, Style Sheets and further markup languages.
[0034] In using HTML, there are two choices that determine the size of the final output: target page width and font size. One page width to select is the screen resolution width of an average user, for instance 800 pixels. An alternative is to assume the width of a standard letter-size page, 8.5 inches. Similarly, font size can be chosen to match the default setting on a standard Web browser, e.g., 12 point Times Roman font for variable-width characters.
[0035] Tools for rendering PDF files are known in the art. Since PDF includes information about page size, orientation, and font size, no further information is required.
[0036] Tools for rendering Postcript™ files are known in the art. Since Postcript™ includes information about page size, orientation, and font size, no further information is required.
[0037] In addition to the methods above that relate to computer-generated documents, any paper document can also be used as input. A scanning device which is known in the art can turn the paper document directly into a color bitmap per page.
[0000] Feature Extraction
[0038] After image bitmaps are obtained for individual document pages, conventional document analysis techniques may be applied to extract visual features. Commercial OCR systems such as Xerox ScanWorX commonly provide basic layout information and character interpretations. A single document page is often decomposed into blocks of text, pictures, or figures. For text blocks, word bounding boxes and font size are estimated. Since most commercial systems operate on binary or gray scale images, color images can be converted to a monochrome version first for block analysis. Color constituents can be subsequently extracted by superimposing the color image with segmented block information.
[0039] The end result of document analysis is a set of feature descriptions for each document page. More specifically, for each page, a list of segmented blocks is obtained. Each segmented block is categorized as text, a picture, or line art. The location and color composition of each block are also known. In order to proceed to use the algorithm described above, a suitable representation should be chosen. Therefore, it is assumed that a simple statistical representation is used, although other representations, even symbolic, are also possible.
[0040] A document image is divided into m×n grids. For each uniquely numbered square in the grid, g i ,1≦i≦m·n, five features are recorded. The first three features, t i , p i , and f i , indicate portions of the grid area which overlap with a text, picture or line art block, respectively. For example, if entire area under the grid belongs to a text block, t i =1, p i =f i =0. If the left one third area overlaps a text block, the right one third overlaps a picture, and the middle one third contains white background, then t i =p i =0.33 and f i =0. The next two features, b i and c i , contain the color information of grid content. Colors may be represented by their brightness, hue, and saturation attributes. The brightness attribute represents the observed luminance and is monochromatic. The hue attribute indicates the degree of “redness” or “greenness”. The saturation attribute reflects the pureness of the hue. Although human perception is more sensitive to certain color tone than others, it is assumed that visual significance is independent of the hue in the simplified representation and only the “average brightness” and “average color pureness” is recorded. Feature b i measures the average “blackness” inside a grid. More precisely, it is the average brightness value for pixels in the grid in reverse and normalized such that if all pixels inside a grid are pure black, b i =1. This feature is equivalent to the “ink density” feature frequently used in conventional document analysis of bitonal images. Feature c i is the average saturation value for pixels in the grid, also normalized between 0 and 1. Therefore, a grayscale image has only a brightness value but no saturation attribute. In contrast, a grid containing color pixels will have a non-zero c i value.
[0041] Consequently, the visual information in a given page is represented by a vector with dimension 5*m*n, which can be considered as a concatenation of 5 vectors , , , , each of m*n dimensions. A document consisting of k pages will be represented by k vectors 1 . . . k . Elements in these vectors all have values between 0 and 1. However, they do not have to sum to 1.
[0000] Visual Saliency Evaluation
[0042] The simplest form of visual saliency is evaluated on a per-page basis independent of other pages in the same document or database. This is achieved by assigning a weight to each visual features. For example, since colors are more noticeable than grays, and pictures are more visually significant than line arts and text, a reasonable weighting for the 5 features is w t =0.1, w f =0.4. w p =1, w b =0.8, w c =2. The saliency score for a page is then computed as
Saliency ( v ) > = w t · ∑ i t i + w f · ∑ i f i + w p · ∑ i p i + w b · ∑ i b i + w c · ∑ i c i
[0043] Although, in this example, the weights are applied uniformly across the page, the weights may be made to reflect the positional variance in human perception. For instance, different weights may be assigned to w c (i) depending on the location of (i) to emphasize the significance of colors when occurring in the middle of a page versus on the top or bottom of a page. Therefore, a more general equation for saliency is
Saliency ( v ) > = ∑ i w t ( i ) · t i + ∑ i w f ( i ) · f i + ∑ w p ( i ) · i p i + ∑ i w b ( i ) · b i + ∑ i w c ( i ) · c i
[0044] Using the function Saliency, pages in a document can thus be ranked according to visual distinctiveness, and selected to represent the document, as shown in FIG. 2A .
[0000] Relative Saliency
[0045] Since one purpose of using visually salient icons is to aid the retrieval of documents, in one embodiment, the icon selection criterion considers common characteristics of other documents in the collection of documents. For example, the significance of a page containing a red picture in one comer is diminished if all pages in the database have the same characteristic. This situation is quite possible in special collections where all documents contain the same logo or other types of marking. This problem is known in information retrieval and is typically dealt with by incorporating a database norm into the equation. By using a centroid subtraction method, similar types of correction mechanisms may be applied to the techniques described herein.
[0046] Given a collection of documents, the centroid is the average visual feature vector of all pages. To discount properties common to all documents in the database, the centroid is subtracted from individual feature vectors before saliency calculation. In other words,
RelSaliency( )=Saliency(| − |)
where {right arrow over (u)} is the centroid vector. Thus, in one embodiment, saliency is evaluated based on features that are “out-of-normal” in the database. Using the example presented above, if all pages in the database contain a red picture at grid position i, then the average value of c i will be fairly high. Therefore, a page that does not have a red picture in the comer should be more noticeable. In this case, if c i =0 in this page, which a high value will result after subtracting the average c i in the centroid. In this example, since we are ignoring hue, a page that has a picture in that position, regardless of color, will have a high c i value. In contrast, a page that does not have any color in that position will stand out.
Visual Distance
[0047] To measure the visual difference between two pages, the Saliency function may be applied to the absolute values of the differences between corresponding features.
VisualDist( 1 , 2 )=Saliency(| 1 − 2 |)
[0048] VisualDist takes a grid by grid accounting of the discrepancies in texture and color between at least two pages and then assesses the visual saliency of the total difference. The portion | 1 − 2 | generates a vector whose elements are all between 0 and 1. While the L 2 norm is most frequently used (or rnisused) to measure the distance between two vectors regardless whether a uniform numeric scale applies to all components, this measure appears to be more suitable to describing what a visual difference is and how visually significant that difference may be.
[0049] One application of the visual distance is to produce a condensed representation of a multi-page document, as shown in FIG. 3 . The visual difference between every two consecutive pages determines the amount of overlapping that exists; therefore, only significantly different-looking pages are shown in full. Since VisualDist is a distance metric, it can be used to cluster all pages in a document, or pages in a collection of documents. Pages are first grouped by their visual similarities. Thereafter, an exemplar page for each cluster is selected by picking the page whose feature vector is closest to the duster center. This produces the exemplar pages of a document as seen in FIG. 2B .
[0000] Icon Display
[0050] It will be appreciated that although FIGS. 2A, 2B , 3 illustrate example of displays of icons created using the techniques of the invention, other arrangements are possible. The scheme may adapt to the amount of space available by picking out a smaller or a larger number of page icons. The amount of space can be specified by an external constraint (e.g., physical display size), by a system designer, or by a user (e.g., if the icon is displayed within a resizable box), the amount of space can also be a variable. For example, the number of page icons that are shown may depend on the number of clusters found within the document, the length of the document, the number of pages whose visual saliency is above some predetermined threshold, or the connection bandwidth.
[0051] The scheme of icons may adapt to the shape of the space available. FIG. 3 shows a linear display. The same information may be shown as a sequence of lines of page icons, for a square or rectangular shape, or as stacks of distinct-looking pages. Alternatively, the icons may be arranged around a circle or oval. In general, an ordered set of icons may follow any arbitrary path.
[0052] The generated icons are suitable for use in a graphical user interface, where they can be generated on-the-fly, for printed use, where they are generated ahead of time, or for use on the Web or in multimedia presentation formats.
[0053] FIG. 4 illustrates one embodiment of a computer system 10 which implements the principles of the present invention. Computer system 10 comprises a processor 17 , a memory 18 , and interconnect 15 such as a bus or a point-to-point link. Processor 17 is coupled to memory 18 by interconnect 15 . In addition, a number of user input/output devices, such as a keyboard 20 and display 25 , are coupled to a chip set (not shown) which is then connected to processor 17 . The chipset (not shown) is typically connected to processor 17 using an interconnect that is separate from interconnect 15 .
[0054] Processor 17 represents a central processing unit of any type of architecture (e.g., the Intel architecture, Hewlett Packard architecture, Sun Microsystems architecture, IBM architecture, etc.), or hybrid architecture. In addition, processor 17 could be implemented on one or more chips. Memory 18 represents one or more mechanisms for storing data such as the number of times the code is checked and the results of checking the code. Memory 18 may include read only memory (“ROM”), random access memory (“RAM”), magnetic disk storage mediums, optical storage mediums, flash memory devices, and/or other machine-readable mediums. In one embodiment, interconnect 15 represents one or more buses (e.g., accelerated graphics port bus, peripheral component interconnect bus, industry standard architecture bus, X-Bus, video electronics standards association related to buses, etc.) and bridges (also termed bus controllers).
[0055] While this embodiment is described in relation to a single processor computer system, the invention could be implemented in a multi-processor computer system or environment. In addition to other devices, one or more of network 30 may be present. Network 30 represents one or more network connections for transmitting data over a machine readable media. The invention could also be implemented on multiple computers connected via such a network.
[0056] FIG. 4 also illustrates that memory 18 has stored therein data 35 and program instructions (e.g. software, computer program, etc.) 36 . Data 35 represents data stored in one or more of the formats described herein. Program instructions 36 represent the necessary code for performing any and/or all of the techniques described with reference to FIGS. 2A, 2B and 3 do. Program instructions may be stored in a computer readable storage medium, such as any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, ROMs, RAMs, erasable programmable read only memories (“EPROM”s), electrically erasable programmable memories (“EEPROM”s), magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus. It will be recognized by one of ordinary skill in the art that memory 18 preferably contains additional software (not shown), which is not necessary to understanding the invention.
[0057] FIG. 4 additionally illustrates that processor 17 includes decoder 40 . Decoder 40 is used for decoding instructions received by processor 17 into control signals and/or microcode entry points. In response to these control signals and/or microcode entry points, decoder 40 performs the appropriate operations.
[0058] In the preceding detailed description, the invention is described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. | A system and a method for visually summarizing a document comprising a display, a processor coupled to the display, and a memory coupled to the processor. Stored in the memory is a routine, which when executed by the processor, causes the processor to generate display data. The routine causes the processor to generate data through extracting at least one visual feature from a document having a plurality of pages, ranking the pages in a document, selecting a page for representing a document according to the visual feature, and displaying the selected page as display data. | 8 |
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