description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
This invention relates generally to a device for severing thread in a textile loom and particularly to a device for severing the weft thread of a shuttleless loom.
Heretofore various types of thread severing devices have been known which utilize either scissor action or an anvil and chisel for severing the weft thread of a shuttleless loom. One such device is described in U.S. Pat. No. 3,951,179 to Pfarrwaller. The device described therein has an an object the minimization of wear in such a thread severing device. The disclosure in Pfarrwaller U.S. Pat. No. 3,951,179 is hereby incorporated by reference. The problem pronounced by Pfarrwaller is a persistent problem in all severing devices since such machines tend to severe weft threads at a rate on the order of 200 to 600 severences per minute. It is thus seen that such devices are subjected to considerable wear which was heretofore caused considerable loom down time for maintenance and replacements of worn parts.
SUMMARY OF THE INVENTION
It is thus an object of this invention to provide a severing device for the weft thread of a loom which is not subject to the wear which is brought about with conventional severing mechanisms.
It is a further object of this invention to provide a novel severing device which is operable for periods of time considerable longer than the prior art devices before the need for maintenance arises.
These as well as other object are accomplished by a severing device which comprises two scissor sections which define between them a raceway for placement of ball bearings to thereby eliminate wear between adjacent faces of the scissor sections.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an assembly view in perspective of a severing device in accordance with this invention.
FIG. 2 of the drawings is a plan view of the severing device in accordance with this invention.
FIG. 3 of the drawings illustrates the severing motion of the device in accordance with this invention.
FIG. 4 is a sectional view along the line 4--4 of FIG. 2.
FIG. 5 is an enlarged break away view of the bearing and raceway on the right side of FIG. 4.
FIG. 6 is a view along the line 6--6 of FIG. 1.
DETAILED DESCRIPTION
In accordance with this invention it has been found that a scissor type severing device may be utilized without the wear and down time normally associated with prior art scissor devices. This lack of wear has been surprisingly found to be brought about by the placement of ball bearings between scissor sections together with bearings between the moveable scissor section and axle therefor. Various other advantages and features will become apparent from a reading of the following description with reference to the various figures and drawings.
FIG. 1 of the drawings illustrates the severing device 1 of this invention in a perspective assembly view, while FIG. 2 illustrates in plan view the severing device and generally illustrates its scissor like characteristics.
FIG. 3 of the drawings illustrates the movement associated with the severing device of this invention when the device is installed as a loom component. The severing device is generally utilized on the type of loom described in the above referenced patent to Pfarrwaller which is herewith incorporated by reference. In such instances the axle 3 of the severing device is directly coupled with the machine drive of the loom such that the device 1 as illustrated in FIG. 3 reciprocates vertically from the solid line position of FIG. 3 to the dotted line position indicated at 1' in FIG. 3 whereby followers 5 and 7 ride vertically through slots 9 and 11 such that when the device 1' is at the lowermost position the scissor blades are open and ready to receive thread. Upon movement toward the uppermost vertical extent, the blades begin to close due to the varing distance between slots 9 and 11. Upon reaching the uppermost extent, the scissor blades severe the thread which has crossed between the open scissor blade sections.
Since this device operates in unison with the loom drive mechanism the severing step is carried out at a frequency of approximately 200 to 600 per minute. The potential for wear associated with such movement is apparent but is overcome by the structure to be described with reference to FIG. 1. Other means for initiating scissor action may be provided such as cam action but the frequency of severing action remains at a high level.
The wear minimization within the severence device of this invention comprises a stationary scissor section 15 which is fixedly attached to axle 3 as can best be seen in FIG. 4 by rivoting thereto at 19. Stationary scissor section 15 defines a groove 21 in the inner surface 23 thereof. Groove 21 is generally concentric with the axis 25 of axle 3.
A rotable scissor section 27 is rotable about axis 3 and has a mating groove therein 29 which abuts and mates with the complimentary groove 21 whereby the two grooves form a raceway between the two scissor sections. Ball bearings 31 fill the raceway and thus generally prevent wear by preventing abutting surfaces from rubbing and providing a rolling relationship therebetween. This is best illustrated in FIG. 4.
A highly preferred feature of this invention comprises the formation of grooves 21 and 29 such that each comprises two surfaces such as 41 and 43 which intersect the inner surface such as 23 at differing angles. The utilization of differing angles causes the ball bearing to move in a spiraling manner whereby wear is evenly distributed and does not result in any flattening of surfaces upon the ball bearings.
Additionally a ball bearing casing 51 is provided between rotable scissor section 27 and axle 3. Shims 53 and 55 are illustrated for housing the bearing case within the inner surface 57 of rotable scissor section 27. The utilization of a disc spring 59 is preferred in order to maintain some resiliency between the scissor sections and to thus permit ball bearings 31 to act as thrust bearings between the two surfaces.
In order to give some guidance as to the specifics of the structure, it is preferred that surface 21 intersect the extended intersurface 23 at an angle of 53 degrees while surface 43 intersects at an angle of about 40 degrees to maintain an eighth inch diameter ball bearing therein.
It has been found that the structure above described may be utilized on a shuttleless loom for many hours of operations in excess of that provided by prior art devices without experiencing deleterious wear. As many variations will become apparent to those that are skilled in the art from the reading of the above exemplarily disclosure such modification are included within the spirit and scope of this invention as defined by the following appended claims.
FIG. 6 illustrates the structure of blades 61 and 63 so as to overcome the gap 65 between surface 23 and lower surface of section 27. | A severing device for use on a shuttleless loom comprises scissor sections defining raceways for maintenance of a thrust ball bearings therebetween. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an aqueous spin finish, a process for treating polyamide yarn therewith and to polyamide yarn treated therewith. The spin finish has improved thermal stability which results in lower emissions during treatment of tire cord formed from polyamide yarn treated with the spin finish. Cord to rubber adhesion is also improved.
2. Description of the Prior Art
Many of the known spin finishes for polyamide yarn flash off during high temperature processing of the yarn or cord formed therefrom. Others cause excessive loss of strength during cording operations. Still others fail to have emulsion stability or provide insufficient yarn lubrication.
Representative prior art patents include U.S. Pat. Nos. 3,103,448 to Ross; 3,428,560 to Olsen; and 3,560,382 to Finch. Spin finishes for polyamide yarn which include an oxidized polyethylene are disclosed in U.S. Pat. Nos. 3,917,893 to Marshall et al. and 4,129,507 to Marshall et al. A spin finish for polyamide yarn which includes an effective amount of a biocide, preferably 2[(hydroxymethyl)amino] ethanol, is disclosed in U.S. Pat. No. 4,191,656 to Marshall. Other prior art patents of interest are U.S. Pat. Nos. 3,113,369 to Barrett et al.; 3,470,095 to Pontelandolfo and 3,785,973 to Bernholz et al.
None of the prior art teaches the required combination of ingredients to achieve the specific beneficial results of the spin finish of this invention.
SUMMARY OF THE INVENTION
The present invention provides an aqueous spin finish, (oil in water emulsion), a process for treating polyamide yarn therewith and to polyamide yarn treated therewith.
The oil portion of the spin finish comprises a rearranged glyceride, ethoxylated oleyl alcohol, ethoxylated nonyl phenol, ethoxylated castor oil, an oxidized polyethylene, a non-nitrogen nonionic emulsifier for the oxidized polyethylene, and an alkali hydroxide. The pH of the spin finish ranges from 7 to 12, more preferably from about 7.3 to 9.7. The preferred weight percents of the components of the oil portion are as follows: about 24.7 to 65, more preferably about 39 to 60, weight percent of the rearranged glyceride; about 5 to 30, more preferably about 15 to 25, weight percent of ethoxylated oleyl alcohol wherein the ethoxylated oleyl alcohol contains about 6 to 12, more preferably about 8 to 10, moles of ethylene oxide per mole of oleyl alcohol; about 1 to 10, more preferably about 2.5 to 5, weight percent of ethoxylated nonyl phenol wherein the ethoxylated nonyl phenol contains about 2 to 12, more preferably about 5 to 10, moles of ethylene oxide per mole of nonyl phenol; about 5 to 30, more preferably about 10 to 20, weight percent of ethoxylated castor oil wherein the ethoxylated castor oil contains about 2 to 16, more preferably about 4 to 7, moles of ethylene oxide per mole of castor oil; about 1 to 7.4, more preferably about 2.5 to 6, weight percent of the oxidized polyethylene; about 0.2 to 2.0, more preferably about 0.5 to 1.7, weight percent of the emulsifier for the oxidized polyethylene; and about 0.04 to 0.3, more preferably about 0.08 to 0.15, weight percent of the alkali hydroxide. The oil portion comprises about 10 to 35, more preferably about 18 to 22, weight percent of the spin finish. As will be detailed later, it is preferred that an aqueous emulsion of the oxidized polyethylene, emulsifier and alkali hydroxide be combined with an aqueous emulsion of the other components.
Suitable oxidized polyethylene materials preferably have an acid number of about 14 to 32 and a ring and ball softening point of about 100° to 142° C. The ring and ball softening point is determined according to the procedure described in ASTM E-28 and will be referred to in the accompanying specification and claims as the softening point of the oxidized polyethylene. The most preferred oxidized polyethylene has an acid number of about 14 to 18 and a softening point of about 105° to 110° C. Another suitable oxidized polyethylene has an acid number of about 28 to 32 and a softening point of about 138° to 142° C. The preparation of such oxidized polyethylenes is described in Canadian Pat. No. 854,778, issued Oct. 27, 1970, hereby incorporated by reference. See also U.S. Pat. Nos. 3,060,163 to Erchak, Jr., 3,103,448 to Ross, 3,917,893 to Marshall et al., and 4,129,507 to Marshall et al., hereby incorporated by reference.
The rearranged glyceride is preferably derived from coconut oil, a natural triglyceride rich in C 12 lauric acid chain. The coconut oil is transesterified with glycerol trioleate. This results in a triglyceride rich in C 18 unsaturated oleic acid chain. The iodine value is a maximum of 55, this value being a measure of the extent of unsaturation in an organic compound by reaction of iodine across the double bond. This may also be accomplished by alcoholysis using oleyl alcohol in the presence of an acid catalyst. See U.S. Pat. No. 3,785,973 to Bernholz et al.
In this specification and accompanying claims, the phrase "rearranged glyceride" means a triglyceride rich in the C 18 unsaturated oleic acid chain. This triglyceride can be formed by either of the above-mentioned methods, i.e., alcoholysis using oleyl alcohol in the presence of an acid catalyst or transesterification of coconut oil with glycerol trioleate.
Any suitable non-nitrogen nonionic emulsifying agent may be used in emulsifying the oxidized polyethylene used in the present invention. Mixtures of higher fatty acids, for example C 12 to C 20 saturated aliphatic acids, may be used as emulsifiers as may also the alkyl aryl polyether alcohols. Especially useful are the condensation products of ethylene oxide with hydrophobic material such as a long chain aliphatic alcohol, acid, ester, ether or alkyl phenol. These products are characterized by containing as the hydrophilic portion of the molecule, a plurality of oxyethylene moieties as illustrated in the formulae below.
1. R--O--(CH 2 --CH 2 O) X --CH 2 --CH 2 OH wherein R is an alkyl group having from 12 to 22 carbon atoms or an alkyl phenol residue wherein the alkyl group contains from 6 to 13 carbon atoms inclusive and wherein X is at least 4, especially between about 6 and about 40. Commercial examples of products in this group include "Triton X-100" wherein R is an alkyl phenol residue wherein the alkyl group is isooctyl and wherein X is 7 to 9; "Triton X-102" wherein R is an isooctyl phenol residue and X is 11; "Tergitol NPX" wherein R is ethylhexyl phenol residue and X is 8 to 9; "Neutronic 600" wherein R is nonyl phenol residue and X is 9; "Emulphor ELN" wherein R is dodecyl phenol residue and X is 19.
2. Condensation products of fatty acids and polyethylene glycols having the general formula: RCOO-(CH 2 CH 2 O) X CH 2 CH 2 OH wherein R is a long chain alkyl group having from 12 to 18 carbon atoms inclusive and X is an integer from 8 to 40 inclusive.
3. Polyoxyethylene derivatives of hexitol anhydride or sorbitol fatty acid esters such as "Tween 80".
4. Polyoxyethylene ethers R-O(CH 2 CH 2 O) X CH 2 CH 2 OH wherein R is an alkyl group having from 6 to 18 carbon atoms and X is an integer from 4 to 40 inclusive. The preferred emulsifiers are the alkyl phenols, most especially Triton X-100.
Alkali hydroxides suitable for use in the present invention include sodium hydroxide, potassium hydroxide and ammonium hydroxide, most preferably the former. The alkali hydroxide, preferably in solution, neutralizes the acid function of the polymer, i.e., the oxidized polyethylene, and is critical in making the polyethylene emulsion and consequently, the spin finish.
It is preferred that the spin finish of the present invention further comprises a biocide. Any biocide is satisfactory that does not lower the pH of the spin finish below about 7; at a pH of below about 7, the spin finish becomes unstable and the polyethylene wax plates out or deposits on the processing equipment. The pH of the spin finish which contains the biocide may range from about 8 to 10, more preferably about 9.1 to 9.4. When a biocide is utilized, it may comprise about 0.02 to 0.5, more preferably from about 0.05 to 0.15, weight percent of the spin finish. Various biocides for control of bacteria in spin finish emulsions used on polyamide yarn are disclosed in U.S. Pat. No. 4,191,656 to Marshall, hereby incorporated by reference; the biocide constituting a part of that invention, 2[(hydroxymethyl)amino] ethanol, is the preferred biocide for use in the spin finish of the present invention, if a biocide is to be used.
The present invention further provides a polyamide yarn treated with the spin finish composition as above defined. The present invention also provides, in a process for the production of polyamide yarn, the improvement which comprises treating the yarn during spinning with an aqueous spin finish as above defined. It is preferred that approximately 0.01 to 2.0 weight percent, based on the weight of the yarn, of the oxidized polyethylene be retained on the yarn.
The strip adhesion test utilized in illustrating the present invention is defined in U.S. Pat. No. 3,940,544 to Marshall et al., hereby incorporated by reference.
The test for cord wicking is as follows. A yarn sample about 24 inches (61.0 cms.) in length is tied at one end to a 150 gram weight and is tied at its other end to the bottom of a basin which contains a liquid. The yarn sample is suspended over a pulley intermediate its two ends to provide a measuring surface of about 10 inches (25.4 cms.). The height (in millimeters) reached by the liquid on the yarn in one minute is the cord wicking value. Wicking is a measure of the wetting of the yarn, the higher the value the better.
Breaking strength is defined at ASTM D 885-78, Section 3.4 as "the ability or capacity of a specific material to withstand the ultimate tensile load or force required for rupture". The procedure for testing breaking strength (load) of conditioned yarns and cords is described in ASTM D 885-78, Section 15. The procedure for obtaining the elongation at break (percent) of conditioned yarns and cords is described in ASTM D 885-78, Section 18.
TABLE I______________________________________Finish Compositions - Oil Portion______________________________________ Weight PercentComponent A B C D______________________________________Coconut oil -- -- -- 51.7Rearranged glyceride -- 51.2 51.2 --POE (9).sup.1 oleyl ether -- 23.3 -- --POE (10).sup.1 oleyl ether -- -- 23.3 23.5POE (9).sup.1 nonyl phenol -- 4.6 4.6 4.7POE (5).sup.1 castor oil -- 14.0 14.0 14.1A-C® polyethylene 680.sup.2 6.8 5.4 5.4 4.9A-C® polyethylene 392.sup.3 -- -- -- --Triton X-100.sup.4 -- 1.4 1.4 1.0Sodium hydroxide -- 0.1 0.1 0.1Mineral oil.sup.5 48.2 -- -- --POE (7).sup.1 oleyl phosphate 38.4 -- -- --NEKAL WS-25.sup.6 6.6 -- -- --POE (7).sup.1 cetyl-stearylalcohol phosphate -- -- -- --AEROSOL TR-70.sup.7 -- -- -- --POE (16).sup.1 hydrogenatedcastor oil -- -- -- --______________________________________ Weight PercentComponent E F G H______________________________________Coconut oil 51.7 55 -- --Rearranged glyceride -- -- 50.8 50POE (9).sup.1 oleyl ether -- -- -- --POE (10).sup.1 oleyl ether 23.5 25 23.1 --POE (9).sup.1 nonyl phenol 4.7 5 4.6 --POE (5).sup.1 castor oil 14.1 15 13.8 --A-C® polyethylene 680.sup.2 -- -- -- --A-C® polyethylene 392.sup.3 4.9 -- 5.9 --Triton X-100.sup.4 1.0 -- 1.7 --Sodium hydroxide 0.1 -- 0.1 --Mineral oil.sup.5 -- -- -- --POE (7).sup.1 oleyl phosphate -- -- -- --NEKAL WS-25.sup.6 -- -- -- --POE (7).sup.1 cetyl-stearylalcohol phosphate -- -- -- 30AEROSOL TR-70.sup.7 -- -- -- 3.0POE (16).sup.1 hydrogenatedcastor oil -- -- -- 17______________________________________ Footnotes to Table I .sup.1 Moles of ethylene oxide per mole of base material. .sup.2 Allied Chemical Corporation's trade name for an oxidized polyethylene having an acid number of about 14 to 18 and a softening poin of about 105° to 110° C. .sup.3 Allied Chemical Corporation's trade name for an oxidized polyethylene having an acid number of about 28 to 32 and a softening poin of about 138° to 142° C. .sup.4 Rohm & Haas Company's trade name for polyoxyethylene 9-10 octyl phenol. .sup.5 White mineral oil having a viscosity of about 100 S.U.S. at 100° F. (37.8° C.) and a boiling point of about 297° to 458° C. (568° to 855° F.). .sup.6 GAF's trade name for solution consisting of 75 percent sodium dinonyl sulfosuccinate, 10 percent isopropanol and 15 percent water. .sup.7 American Cyanamid's trade name for a solution consisting of 70 percent sodium di(tridecyl) sulfosuccinate, 20 percent ethanol and 10 percent water.
TABLE II______________________________________ Example Control 1 2 3 4______________________________________Spin Finish - Oil Portion A B C DBiocide - Troysan 174.sup.1 -- 0.1 0.1 0.1Greige Cord.sup.2 :Breaking strength (lbs.) 70.5 70.2 70.2 70.6Elongation at break (%) 29.7 29.8 29.8 29.5Wicking (mm.) - Water 52 47 47 27Wicking (mm.) - ARFL.sup.3 23 21 21 8Wicking (mm.) - MRFL.sup.4 22 22 22 5Treated Cord.sup.5 :Breaking strength (lbs.) 72.2 73.2 73.2 72.1Elongation at break (%) 25.3 25.4 25.4 25.5Adhesion - Pounds pull 37 36 37 31Adhesion - Visual rating 5.0 4.9 5.0 5.0______________________________________ Example 5 6 7 8______________________________________Spin Finish - Oil Portion E F G HBiocide - Troysan 174.sup.1 0.1 0.1 0.1 0.1Greige Cord.sup.2 :Breaking strength (lbs.) -- -- 71.4 68.5Elongation at break (%) -- -- 27.9 27.0Wicking (mm.) - Water 12 14 48 47Wicking (mm.) - ARFL.sup.3 7 6 22 15Wicking (mm.) - MRFL.sup.4 6 7 21 21Treated Cord.sup.5 :Breaking strength (lbs.) -- -- 70.9 68.1Elongation at break (%) -- -- 23.3 22.8Adhesion - Pounds pull -- -- 36 37Adhesion - Visual rating -- -- 5.0 4.8______________________________________Footnotes to Table II.sup.1 Troy Chemical Company's trade name for 2[(hydroxy-methyl)amino]ethanol..sup.2 Twisted cord with no further treatment such asdipping.sup.3 Liquid composition comprising by weight percent:Styrene butadiene vinyl pyridine latex 20.8Resorcinol 2.24Ammonium hydroxide 1.96Formaldehyde 1.16Sodium hydroxide 0.061Water 73.8 100.0These percentages are based on theoretical 100%concentrations of reagents. Allowance should bemade in practice for the strengths commonly met,e.g., ammonium hydroxide 28%..sup.4 Liquid composition similar to that of footnote 3with the substitution of a 50/50 mixture of avinyl pyridine latex (41.8% solids) and syntheticbutyl rubber latex (39.3% solids) for the styrenebutadiene vinyl pyridine latex..sup.5 Twisted cord which has been treated with a standardresorcinol-formaldehyde-latex dip and processed athigh temperature (200°-205° C.) in the conventionalmanner.______________________________________
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of this invention may be briefly stated as follows: A spin finish, particularly for continuous filament polyamide yarn to be processed into tire cord, the finish being an oil in water emulsion of about 18 to 22 percent by weight of the oil portion, the oil portion comprising about 39 to 60 weight percent of a rearranged glyceride; about 15 to 25 weight percent of ethoxylated oleyl alcohol containing about 8 to 10 moles of ethylene oxide per mole of oleyl alcohol; about 2.5 to 5 weight percent of ethoxylated nonyl phenol containing about 5 to 10 moles of ethylene oxide per mole of nonyl phenol; about 10 to 20 weight percent of ethoxylated castor oil containing about 4 to 7 moles of ethylene oxide per mole of castor oil; about 2.5 to 6 weight percent of oxidized polyethylene having an acid number of about 14 to 18 and a softening point of about 105° to 110° C.; about 0.5 to 1.7 weight percent of ethoxylated octyl phenol containing about 9 to 10 moles of ethylene oxide per mole of octyl phenol; about 0.08 to 0.15 weight percent of sodium hydroxide; and about 0.05 to 0.15 weight percent of a biocide, specifically 2[(hydroxymethyl)amino]ethanol; the spin finish having a pH of about 9.1 to 9.4.
Formulation of the spin finish is preferably as follows. An aqueous emulsion of the oxidized polyethylene is prepared having the following composition:
______________________________________ Weight Parts Percent______________________________________Oxidized polyethylene 38 19POE (9-10) octyl phenol 10 520% aqueous NaOH solution 3 1.5Water 149 74.5______________________________________
The wax and the emulsifier are melted together at 125° C. (257° F.) maximum and when completely melted, are cooled to 110° C. (230° F.). With the melt temperature at 110° C. (230° F.), the sodium hydroxide solution is added with stirring to break up the foam which forms. The water is heated to boiling. The melt at 110° C. (230° F.) is slowly added with rapid stirring to the water which has been maintained at a temperature of 95° to 99° C. (203°-210° F.). The emulsion is then allowed to cool to 40°-50° C. (104°-122° F.) with moderate stirring. Water is added to replace water lost due to evaporation.
A 20 percent oil in water emulsion is formed utilizing the other spin finish components (except the biocide).
______________________________________ Weight Parts Percent______________________________________Water 80 80Rearranged glyceride 11 11Ethoxylated oleyl ether 5 5Ethoxylated nonyl phenol 1 1Ethoxylated castor oil 3 3______________________________________
The oil portion and water are both heated to 60° C. (140° F.), and the oil is added to the water with agitation. The emulsion is cooled to room temperature, about 30° to 35° C. (86° to 95° F.)
The polyethylene emulsion is added to the oil in water emulsion at room temperature, about 30° to 35° C. (86° to 95° F.), at a ratio or weight percent of about 5.75 to 94.25. About 0.1 weight percent of the biocide is added to the emulsion. This spin finish has its oil portion identified as B in Table I.
The invention will now be further described in the following specific examples which are to be regarded solely as illustrative and not as restricting the scope of the invention. In the following examples, parts and percentages employed are by weight unless otherwise indicated.
EXAMPLE 1
Polycaproamide pellets having a relative viscosity of about 85 as determined at a concentration of 11 grams of polymer in 100 ml. of 90 percent formic acid at 25° C. (ASTM D-789-62T) and having about 70 total end groups were melt extruded at a temperature of about 275° C. and at a rate of about 50 pounds per hour and under pressure of about 2800 psig. through a 204-orifice spinnerette to produce an undrawn yarn having about 5590 denier. The yarn was quenched utilizing the apparatus of U.S. Pat. No. 3,619,452 to Harrison et al., hereby incorporated by reference. A 20 percent oil in water emulsion was formed utilizing oil portion A of Table I. This finish composition was applied to the yarn as a spin finish in amount to provide about 0.01 to 2.0 weight percent, based on the weight of the yarn, of oxidized polyethylene on the yarn. The yarn was then heated and drawn over a ceramic pin on a conventional drawtwist machine to about 5 times its extruded length to produce a 1260 denier yarn. The drawtwister heater was at a temperature of about 190° C. During the drawing of this control yarn, offensive smoke and fumes were given off.
The control yarn was twisted into three-ply cords and prepared for tire application by treatment with a standard resorcinol-formaldehyde latex dip and processing at high temperature (200° to 205° C.) in the conventional manner. The twisted cord was tested before (greige cord) and after treatment for the properties set forth in Table II.
EXAMPLES 2-8
The procedure of Example 1 was repeated for Examples 2 through 8 except that the oil portions B through H respectively, described in Table I, were utilized in forming the spin finish. Table II sets forth properties for twisted cords made from yarn produced in each example.
The spin finishes utilizing oil portions B and C of Table I were formulated in accordance with the description of the preferred embodiment. Spin finishes utilizing oil portions D and E of Table I were similarly formulated except that the aqueous emulsion of the oxidized polyethylene had the following composition:
______________________________________ Weight Parts Percent______________________________________Oxidized polyethylene 50 25POE (9-10) octyl phenol 10 520% aqueous NaOH solution 3 1.5Water 137 68.5______________________________________
Also, the polyethylene emulsion was added to the oil in water emulsion at a ratio or weight percent of about 4 to 96. The spin finish utilizing oil portion G of Table I was similarly formulated except that the aqueous emulsion of the oxidized polyethylene had the following composition:
______________________________________ Weight Parts Percent______________________________________Oxidized polyethylene 34 17POE (9-10) octyl phenol 10 520% aqueous NaOH solution 3 1.5Water 153 76.5______________________________________
Also, the polyethylene emulsion was added to the oil in water emulsion at a ratio or weight percent of about 7 to 93. The remaining spin finishes, i.e., those utilizing oil portions F and H of Table I (Examples 6 and 8), were 20 percent oil in water emulsions formulated by heating the oil and water separately to 60° C. (140° F.) and adding the oil to the water with agitation.
DISCUSSION
With reference to Table II, the values for the properties set forth for the control (Example 1) were the target values for a superior, nonfuming spin finish. The spin finishes of Examples 4, 5 and 6 had extremely low cord wicking values, apparently independent of the presence or lack of an oxidized polyethylene; note, however, that the oil portions of those spin finishes, i.e., D, E and F respectively, included coconut oil rather than the rearranged glyceride as its lubricant. Also, the spin finish of Example 8, which did not include an oxidized polyethylene, had very low breaking strength values; note, however, that oil portion H of this spin finish included the rearranged glyceride rather than coconut oil as its lubricant. It is apparently important, therefore, that both an oxidized polyethylene and the rearranged glyceride be components of the desired spin finish. Examples 2, 3 and 7 (Table II) are the nonfuming spin finishes forming a part of the present invention. In this regard, the spin finishes of Examples 2 and 3, which include an oxidized polyethylene having an acid number of about 14 to 18 and a softening point of about 105° to 110° C., are preferred to that of Example 7, which includes an oxidized polyethylene having an acid number of about 28 to 32 and a softening point of about 138° to 142° C.; this is due to the fact that on occasion the oxidized polyethylene of the latter spin finish deposits on the processing equipment and plates out. | An aqueous spin finish, a process for treating polyamide yarn therewith and polyamide yarn so treated are all disclosed. The oil portion of the spin finish comprises a rearranged glyceride, ethoxylated oleyl alcohol, ethoxylated nonyl phenol, ethoxylated castor oil, an oxidized polyethylene, a non-nitrogen nonionic emulsifier for the oxidized polyethylene, and an alkali hydroxide. The spin finish has a pH of about 7 to 12. The spin finish has improved thermal stability which results in lower emissions during treatment of tire cord formed from polyamide yarn treated with the spin finish. Cord to rubber adhesion is also improved. | 3 |
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
The present invention relates to illuminative apparatus, more particularly to illuminative apparatus of the type wherein starting means is employed for preheating the electrodes of a fluorescent lamp.
Conventional fluorescent lamps are electric discharge lamps in which gas ionizes and produces radiation which activates fluorescent material inside glass tubing. Generally, a fluorescent lamp includes a phosphor-coated tubular bulb which has electrodes sealed into each end and which contains mercury vapor at low pressure along with an inert starting gas (e.g., argon or an argon-neon mixture). The tubular bulb has been practiced in a variety of shapes but is usually of straight, U-shaped or circular configuration. When the proper voltage is applied across the ends of the tubular bulb, an arc is produced by current flowing between the electrodes through the fill gas. The ultraviolet energy from the arc excites the phosphor coating to emit light; i.e., the phosphor coating transforms some of the ultraviolet energy generated by the electric discharge into light.
The visual sensation of abrupt change in the illumination intensity or brightness of a stationary object is known as "flicker." "Cyclic flicker" is normally inherent in lighting systems which are supplied with alternating current (ac). The light which is emitted from a fluorescent lamp or an incandescent lamp which is operated on ac circuitry typically executes these cyclic pulsations. The cyclic flicker associated with fluorescent lamps is generally of considerably greater magnitude than the cyclic flicker associated with incandescent lamps. Nevertherless, in normal usage the cyclic flicker associated with either fluorescent lamps or incandescent lamps is generally not readily visible.
Sometimes a fluorescent lamp commences another kind of flicker when it is in a malfunctioning mode, often toward the end of its useful life. This abnormal flicker is referred to herein as "blinking." Blinking, as distinguished from cyclic flicker, is an aberrant phenomenon and frequently is visibly appreciable. Blinking generally results from voltage fluctuations caused by sudden variations in load, and may be regular or irregular. Sometimes blinking regularly recurs in accordance with a regular succession of voltage dips; such regular recurrence may be rapid. Other times blinking recurs irregularly, in terms of frequency of occurrence and/or duration, in accordance with corresponding irregularity of voltage dips.
Blinking not only is energy-inefficient but also forewarns a possible fire hazard. The inordinate heating, by excessive voltage, of a component of the fluorescent lamp circuitry represents a potentially combustible situation. Moreover, fluorescent lighting has been known to interfere with proper functioning of digital computers, televisions, radios, remote control devices and other forms of electronic apparatus. See, e.g., "Interfering Fluorescents," Popular Science, September 1994, page 50. Electronic equipment has been observed to be especially vulnerable to such interference when the infrared signal emissions from a fluorescent lamp are erratic due to voltage fluctuations associated with blinking of the lamp. Although circuit-breaking capability has been known to be utilized in connection with fluorescent illumination, in conventional practice the actual breaking of the circuit may not be effectuated in timely enough fashion to have avoided significant deleterious effects of malfunctioning associated with blinking.
A blinking light may be inconspicuously located. Even when a blinking light is noticeable, its impact upon an observer can vary. The degrees of perceptibility and objectionability of observed fluorescent blinking correspond to the change in light output in terms of frequency and magnitude, and are affected by several factors such as lamp size, lamp type, illumination level, voltage dip rate of change, voltage dip duration, surrounding brightness and the observer's physiology/psychology. See, e.g., Davidson, G. E., "Flicker in Lighting Systems (Effect of Sudden Voltage Dips Studied)," Ontario Hydro Research News, October 1952, vol. 4, no. 4, pages 9-11.
Human nature is such that one may need to be externally motivated in order to act in a responsible manner with regard to some occurrence or state of affairs in one's life. When a blinking fluorescent bulb is noticed, it may not, in and of itself, be annoying or bothersome enough to motivate someone to replace the bulb or otherwise correct the underlying problem, or even to simply terminate operation of the bulb. A person may be particularly neglectful when there remain properly functioning fluorescent bulbs which that person views as sufficiently compensating for the light deficiency or as sufficiently alleviating the disturbance.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of the present invention to provide automatically responsive warning apparatus for alerting people to, or heightening people's awareness of, fluorescent lamp malfunctioning which is manifested by blinking.
Another object of this invention is to provide such apparatus which immediately warns of such malfunctioning and thereby affords the opportunity for remedial action which may avoid or ameliorate one or more deleterious consequences of such malfunctioning, such deleterious consequences including energy waste, lamp damage, fire hazard and electronic interference.
Another object of this invention is to provide such apparatus which immediately warns of malfunctioning and thereby affords, significantly prior to automatic ceasing of operation of a fluorescent lamp which has circuit-breaking capability associated therewith, such opportunity for remedial action.
Another object of the present invention is to provide such apparatus which may be manufactured, installed and implemented in a previously manufactured conventional flourescent lamp.
A further object of this invention is to provide such apparatus which may be manufactured and implemented as part of a conventional flourescent lamp.
A further object of the present invention is to provide such apparatus which is economical and efficient and lends itself to widespread use in association with fluorescent illumination.
A fluorescent lamp is generally operated on ac in series with a choke or ballast which serves to limit current to the electrodes of the bulb. One practiced approach to igniting the lamp is to employ a sufficiently high voltage whereby the lamp immediately strikes. According to more common practice, however, the ignition of the lamp is furthered by thermal emission caused by preheating of the electrodes to an appropriate temperature. A starter is generally employed for purposes of carrying out this preheating. The starter usually includes a glow switch which includes an electron tube containing two strips, at least one of which is bimetal, which are closed when heated by the glow discharge.
In normal operation of a typical glow starter, upon application of the transformer voltage a glow discharge commences between the poles of the starter whereby a heating effect warms the bimetal and causes it to bend over into contact with the other pole. This pole-to-pole contact causes a "short circuit" current through the ballast which heats up the electrodes. This short circuit in the starter causes the glow discharge to cease and, consequently, the bimetal to cool down and break contact. Due to the sudden interruption of the short circuit current, a voltage surge is produced by the ballast and applied over the discharge path in the lamp, causing the lamp to ignite; if the lamp does not ignite, the cycle is repeated as many times as necessary to bring about ignition of the lamp.
An easily ionized inert gas is present in the bulb, in addition to mercury, to facilitate starting. The ballast serves as a current-limiting starting resistor which is used, along with the starter, for igniting the arc in the bulb. For ignition to take place, an arc is first struck between the electrode of the starter and the adjacent electrode of the bulb. The resultant heating and additional ionization from this arc permit the main arc to form between the electrodes of the bulb.
Normally, upon ignition a voltage is maintained across the lamp which is approximately half the open voltage and is insufficient to activate the starter. When blinking occurs, this is an indication that the starter cycle is abnormally being repeatedly initiated. Time and again, the lamp is momentarily lit and immediately unlit due to some malfunction. Each time the lamp is de-ignited, the starter is reactivated.
This repetition of starter actuation accompanied by lamp ignition can bring about "flickering overload," which carries and forewarns possible undesirable consequences. The excessive ac current which is produced by the flickering overload generates excessive heat which can eventually damage the circuitry or lead to fire; in particular, the ballast is susceptible to shorting out or melting when extremely heated due to abnormally long duty cycle. Furthermore, energy is wasted and the potential for radio frequency interference is heightened.
The present invention features alarm means which is responsive to current change associated with fluorescent blinking and which automatically signals upon the occurrence of the fluorescent blinking. Depending upon the embodiment, the alarm includes either or both of an auditory alarm (e.g., sounds a beeper) and a visual alarm (e.g., flashes a light).
In accordance with the present invention, the alarm means which electrically engages the starter means may be either structurally separate from the starter means or structurally coupled with the starter means. Thus, for some embodiments of the present invention the alarm means is preferably embodied as a physically separate mechanism which is made to electrically engage the starter mechanism which is found in a conventional, commercially manufactured preheat-starting fluorescent lamp. For most embodiments of this invention, however, the alarm means preferably is physically coupled with the starter means and thus made an integral part of a multi-functional, uni-structural mechanism which is designed to substitute for the starter unit which is found in a conventional, commercially manufactured preheat-starting fluorescent lamp.
According to the present invention, physical coupling of the alarm means and the starter means can be accomplished by any of various approaches. For some such embodiments the alarm mechanism is preferably made to structurally unite with the starter unit which is found in the commercially manufactured fluorescent lamp; hence, the original starter unit is retained, adapted and supplemented. For other such embodiments the multi-functional starter mechanism which comprises starter means and alarm means is preferably manufactured as a unit which entirely replaces the original starter unit; hence, the original starter unit may be discarded. For yet other such embodiments an entire fluorescent lamp unit is preferably manufactured whereby the multi-functional starter mechanism which comprises starter means and alarm means constitutes a subunit which is "built into" the fluorescent lamp unit.
The conventional commercially made starter mechanism is uni-functional or bi-functional. Some conventional starter mechanisms have the sole function of preheating the electrodes. Other conventional starter mechanisms are additionally equipped with a circuit-breaking capability; many commercially manufactured starter mechanisms include a built-in circuit-breaker which stops the flow of current in the circuit when it is abnormally stressed.
Circuit-breaking means such as circuit-breakers and fuses are well known in the art, and the appropriate implementation of such a protective device as a current-stopping "safety valve" for a fluorescent lighting application is well within the skill of the ordinarily skilled artisan. "Thermal" circuit-breakers and "thermal" fuses, for example, act responsively to excessive heat generated by high voltages. Accordingly, it is recommended practice for many embodiments and applications that the alarm means according to the present invention be accompanied by circuit-breaking means which may serve as a subsequently actuated back-up in the event that the initially actuated alarm means fails to motivate an individual or personnel to remedial action.
The multi-functional, uni-structural starter mechanism in accordance with the present invention is a unit which has the function of preheating the electrodes and the additional function of alarming responsively to current change associated with the occurrence of fluorescent blinking. Most embodiments of the present invention preferably further include the function of breaking the circuit and thereby ceasing operation of the fluorescent lamp at an appropriate time subsequent to commencement of the alarming.
Structurally unitary embodiments of the present invention conveniently and efficiently integrate the preheating function and the alarming function (and for many preferred embodiments, the circuit-breaking function) into a single structural unit which supplants the conventional starter unit. Installation in a fluorescent lamp of this invention's alarming circuitry as part of such an integrated structural unit should be more efficient and cost-effective than installation thereof as a separate structural unit. Moreover, this integrated structural configuration advantageously facilitates electrical engagement of its starter-related electronics with its alarm-related electronics, not only whereby its alarm means is responsive to current fluctuations of its starter means, but also whereby the powering of its alarm means is supplied through its starter means.
Other objects, advantages and features of this invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the present invention may be clearly understood, it will now be described by way of example, with reference to the accompanying drawings, wherein like numbers indicate the same or similar components, and wherein:
FIG. 1 is a schematic electronic diagram of an embodiment of a fluorescent lamp which includes a multi-functional starter unit in accordance with the present invention.
FIG. 2 is a diagrammatic elevated view of an embodiment of the multi-functional starter unit shown FIG. 1, with a portion cut away to show some interior detail.
FIG. 3 is a diagrammatic elevated view as in FIG. 2 of another embodiment of the multi-functional starter unit shown FIG. 1.
FIG. 4 is a schematic electronic diagram of an embodiment of the alarming circuitry pertaining to the starter adjunct of the multi-functional starter unit shown FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, fluorescent lamp 8 has fluorescent bulb 10, starter unit 12 and ballast 14. Fluorescent bulb 10 is operated on ac in series with starter unit 12 and ballast 14. Starter unit 12 is multi-functional in accordance with the present invention. Multi-functional starter unit 12 has a starter tube 15 which has fill gas 24s, left pole 16 (which is made of bimetal) and right pole 18. Left pole 16 is connected to left fluorescent lead 20 and right pole 18 is connected to right fluorescent lead 22. Fluorescent bulb 10 has fill gas 24b, left electrode 26, right electrode 28, two left pins 30 and 32 and two right pins 34 and 36.
Upon application of the line voltage a glow discharge through gas 24s commences between bimetal left pole 16 and right pole 18 whereby a heating effect causes left pole 16 to bend into contact with right pole 18; starter relay 17 between left pole 16 and right pole 18 is now closed. The ensuing short circuit current through ballast 14 heats up electrodes 26 and 28. This short circuit in multi-functional starter unit 12 causes the glow discharge in starter tube 15 to cease and, consequently, left pole 16 to cool down and break contact with right pole 18; starter relay 17 between left pole 16 and right pole 18 is now open. Due to the sudden interruption of the short circuit current, a voltage surge is produced by ballast 14 and applied over the discharge path through gas 24b in bulb 10, causing bulb 10 to ignite.
Voltage across starter relay 17 varies between two voltage levels. When starter relay 17 is closed, the voltage across the relay is or approaches zero. When starter relay 17 is open, the voltage across the relay generally is, depending on the nature of bulb 10 and ballast 14, at least the line voltage (e.g., 110 volts) and can reach or exceed 200 volts.
With particular reference to either FIG. 2 or FIG. 3, and still with reference to FIG. 1, starter unit 12 has commercial starter 38 and starter adjunct 40. Commercial starter 38 is the starter mechanism which was found in conventional preheat-starting fluorescent lamp 8 as originally manufactured and commercially obtained. Adjunct 40 is coupled with commercial starter 38 so as to together provide multi-functional, uni-structural starter unit 12, which has replaced commercial starter 38.
Commercial starter 38, for example standard starter number "FS-40" for 40 watt bulb 10, includes two twist connectors 42 and 44, circuit-breaker 46 and overload switch 48. Left connector 42 is for connecting left pole 16 to left fluorescent lead 20; right connector 44 is for connecting right pole 18 to right fluorescent lead 22. Overload switch 48, which for many such commercial starters 38 includes a red-colored push-button, is activated in order to reset commercial starter 20 once circuit-breaker 46 has been actuated.
Adjunct 40 is an electronics package having case 50 which contains electronic components including high-pitched (e.g., approximately 12 kHz) beeper 52, flashing red light-emitting diode (LED) light 54, left alarm lead 56, right alarm lead 58 and sleeve 60. Left alarm lead 56 is connected to left pole 16; right alarm lead 58 is connected to right pole 18. Left alarm lead 56 and right alarm lead 58 pass through sleeve 60.
Coupling of adjunct 40 with commercial starter 38 is accomplished by any of multifarious means known to the ordinarily skilled artisan. For example, in FIG. 2 case 50 slidably clamps over commercial starter 38. Commercial starter 38 has ridges 62, and case 50 has lips 64, for preventing upcoupling of adjunct 40 and commercial starter 38. Case 50 may be slidably moved a slight distance downward or upward with respect to commercial starter 38, as shown by bidirectional arrow d and distance D. When case 50 is moved sufficiently upward relative to commercial starter 38, overload switch 48 is pushed and thereby activated. In FIG. 3, case 50 is fixedly attached to commercial starter 38; protruding lever 66 mechanically engages overload switch 48 and is pivotable a slight distance downward or upward as shown by bidirectional arrow e and distance E, and thus may be pushed upward to activate overload switch 48.
Still referring to FIG. 1, when fluorescent lamp 8 is properly functioning, starter relay 17 remains open while fluorescent bulb 10 is illuminated. Now referring to FIG. 4, g.p. diode 68 (e.g., 600 V.) rectifies approximately 110 V. ac into direct current (dc). Capacitor 70 (e.g., 50 mfd/250 V. dc) filters (smooths) the dc pulses, which then pass through dropping resistor 72 so that zener diode 74 (e.g., 12 V.) rectifies and charges capacitor 76 (e.g., 2,000 mfd/15 V. dc), which holds the 12 V. dc charge as long as fluorescent bulb 10 remains lit. Hence, in the absence of flickering overload, capacitor 76 remains charged with 12 V., and beeper 52 and LED light 54 remain inactivated.
During improper functioning of fluorescent lamp 8 whereby fluorescent bulb 10 is blinking, starter relay 17 opens when fluorescent bulb 10 is lit and closes when fluorescent bulb 10 is unlit. Often the blinking is attributable to a "weakened" condition of fluorescent bulb 10, which fails to maintain illumination. As this "on again, off again" action of the starting load for left pole 16 and right pole 18 persists, the resultant flickering overload escalates and ballast 14 increasingly overworks and overheats.
During blinking, beeper 52 and LED light 54 each actuate intermittently in accordance with the blinking. Beeper 52 sounds and LED light 54 flashes in virtual concurrence with the state of deillumination of fluorescent bulb 10; beeper 52 is silent and LED light 54 is unlit in virtual concurrence with the state of illumination of fluorescent bulb 10.
Resistor 78 is utilized for LED light 54. Upon deillumination of fluorescent bulb 10, there ceases to be a potential difference across starter relay 17, which is closed. There consequently ceases to be a potential difference between beeper 52 and resistor 78 (e.g., 5 kilohm), whereupon g.p. diode 68 is inactivated, thereby blocking the direct current, and g.p. diode 80 (e.g., 600 V.) is activated, thereby allowing return path of voltage stored in capacitor 76, resulting in actuation of beeper 52 and LED light 54. The direct current charge which has been held by capacitor 76 powers operation of beeper 52 and LED light 54. While fluorescent bulb 10 remains lit, the alarm circuit remains fully charged in anticipation of the eventuality that fluorescent bulb 10 becomes unlit and, concomitantly, beeper 52 and LED light 54 actuate.
When fluorescent bulb 10 reilluminates, the potential difference across starter relay 17, now open, is reestablished; g.p. diode 80 is inactivated, thereby blocking the direct current (and, hence, ceasing return path of voltage stored in capacitor 76), and g.p. diode 68 is activated, thereby allowing rectification of ac into dc, resulting in deactuation of beeper 52 and LED light 54. The circuit through capacitor 70, dropping resistor 72, zener diode 74 and capacitor 76, wherein capacitor 76 holds the direct current charge, is reperpetuated for as long as fluorescent bulb 10 remains lit.
Even when fluorescent lamp 8 is functioning normally, for some embodiments the alarm according to this invention may be momentarily triggered upon "turning on" fluorescent lamp 8. Capacitor 76 may hold some direct current charge while fluorescent lamp 8 is "off;" whether alarm beeping/flashing occurs upon starting fluorescent lamp 8 may relate to the amount of direct current charge which remains held by capacitor 76 while fluorescent lamp 8 is "off," which may depend on the amount of time which has elapsed since fluorescent lamp 8 was last "turned off." Such momentary beeping/flashing upon starting fluorescent lamp 8 should be nonexistent or negligible for most embodiments, and may even be desirable for some applications. If desired, the ordinarily skilled artisan is capable of preventing such start-up alarming, e.g., via blocking circuitry or time-delay circuitry.
Other embodiments of this invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention disclosed herein. Various omissions, modifications and changes to the principles described may be made by one skilled in the art without departing from the true scope and spirit of the invention which is indicated by the following claims. | Alarming mechanism, sounding and/or flashing, which signals fluorescent lamp malfunctioning as visibly manifested by flickering. The alarming mechanism according to this invention electrically engages the starter mechanism of a fluorescent lamp and is responsive to current change associated with abnormal flickering. Timely corrective action which is prompted by the alarm may avoid or mitigate one or more deleterious effects of such malfunctioning, such as energy waste, lamp damage, fire hazard and electronic interference. For many embodiments the alarming mechanism and the starter mechanism are advantageously coupled as a single structural unit. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to a process for balancing a component which may rotate around an axis of rotation as well as to a component to be arranged in the drive train of a motor vehicle for rotation around an axis of rotation, in particular a flywheel.
Rotating parts arranged in the drive train of a motor vehicle, such as the flywheel attached to the crankshaft of an internal combustion engine, the pressure plate unit of a friction clutch mounted on the flywheel, its clutch disc or similar components, for example, are usually balanced by attaching an additional balancing body. Hence, it is known in this context to provide a plurality of openings distributed in peripheral direction on the component to be balanced and then secure balancing bodies or weights corresponding to the measured imbalance in one or several of these openings. It is known from DE-A 2 539 491 to use fastening screws already provided for securing the balancing weights to the rotating component. However, in both variations the number of openings or fastening screws provided restricts the accuracy of the balancing process, if the number of different weight values to be used for the balancing body is not too high. In many cases, it becomes necessary to attach several balancing bodies to various fastening points, and the success of the balancing process must be checked subsequently.
SUMMARY OF THE INVENTION
The invention proposes a process for balancing a rotating component which is simple to apply and does not impair the operational reliability of the rotating component. The invention further proposes a component to be arranged in the drive train of a motor vehicle for rotation around an axis of rotation, in particular a flywheel, which may be balanced in a simple manner and without impairing its operational reliability.
The invention is based on a process with the following steps for balancing a component, which is rotatable around an axis of rotation, in particular a component arranged in the drive train of a motor vehicle:
a) measurement of the size and angle position of an imbalance in the component;
b) provision of a balancing mass arrangement provided to compensate the measured imbalance with at least one balancing body to be attached on the component at a predetermined effective distance from the axis of rotation;
c) attachment of each balancing body provided in step b) at the predetermined effective distance from the axis of rotation and in an angle position on the component selected on the basis of the measured imbalance.
The improvement according to the invention is that balancing bodies provided in step b) have an elongated shape and a length which is greater than half the peripheral length and less than the entire peripheral length of a circle around the axis of rotation with a radius determining the predetermined effective distance; that step b) or step c) covers the shaping of the balancing body to a mass ring, which is not closed in peripheral direction and is interrupted by a gap, with a radius corresponding to the effective distance; and that in step c) each balancing body is secured to the component concentrically to the axis of rotation in such a way as to compensate the imbalance of the component through the gap.
The invention works from the consideration that a gap in a circular mass ring concentric to the axis of rotation generates an imbalance which may be determined exactly. The imbalance corresponds to the size of the missing mass for completion of the mass ring to form a closed ring. Where the material cross-section of the mass ring is predetermined and the specific weight of its material is known, the imbalance of the gap may be determined in advance for the effective distance determined by the radius of the mass ring, or the gap in the mass ring required for a desired imbalance may be fixed. Where a single mass ring is used, the dimensions of the gap are such that the magnitude of the imbalance determined by it is equal to the magnitude of the imbalance measured at the component. The mass ring is then attached with its gap on site, i.e. in the angle position of the measured imbalance, so that the measured imbalance is compensated by the gap. It goes without saying that several mass rings may also be provided to balance the component. The gaps of the mass rings may be offset at an angle to one another so that the measured imbalance of the component is compensated by the resulting imbalance of the mass rings. The use of several mass rings is advantageous if mass rings with their gaps having stepped weight values are to be used. However, the invention allows the component to be exactly and infinitely balanced, in particular when a single mass ring is used it is of advantage that simple, and above all simple to attach, balancing bodies may be used for balancing.
Manufacture of the mass ring is particularly inexpensive if it is cut to lengths from rod-shaped or strand-shaped base material to a length, which leaves the desired gap after shaping into a ring. The balancing body cut from the base material may in this case be bent to form the mass ring before the mass ring is secured to the component in step c).
A circular ring contact surface provided on the component to be balanced and concentric to the axis of rotation can in this case be utilised for radial guidance of the mass ring. For expedience, this contact surface is the inside peripheral surface of a recess in the component to be balanced arranged concentric to the axis of rotation. The mass ring is inserted into the recess in step c), and this simplifies central assembly and supports the mass ring at its outer periphery during operation.
Alternatively, the balancing body cut from the base material may be wound in step c) onto a circumferential contact surface concentric to the axis of rotation of the component to be balanced to follow its longitudinal direction, and be secured to the component at least at intervals. For expedience, the balancing body cut into lengths from the base material is wound around an outer peripheral surface of the component to be balanced, which guides the mass ring being formed during winding on its inside diameter. The mass ring can be secured, for example, to the component by some weld points distributed on the periphery. It must be understood that in individual cases mass rings, which have been bent beforehand, may also be attached to outer peripheral surfaces of the component to be balanced.
The pre-shaping of the cut balancing body into an open mass ring is particularly advantageous when the contact surface is easily accessible in axial direction.
A preferred embodiment provides that for axial guidance, the mass ring is additionally supported on an essentially radially extending contact surface of the component to be balanced. This measure facilitates fastening of the mass ring. A further simplified attachment of the mass ring is achieved if the mass ring is inserted into a groove in the component to be balanced, the cross-section of said groove, at least in a part section, being equal to the material cross-section of the mass ring. The groove adapted to the material cross-section of the mass ring allows the mass ring to be secured beforehand to provide a form-fit so that this may then only have to be locked against twisting as a result of one or several weld points or other fastening means.
The mass ring preferably has a round material cross-section. Such material is particularly inexpensive to obtain when made up into long rods or rolls, and can be cut into lengths practically without waste. However, material with a different cross-section may also be used, e.g. material with a rectangular or square cross-section.
The described contact surfaces of the component to be balanced provided for radial or axial guidance of the mass ring may be smooth in the peripheral direction to simplify manufacture. This may be a cylinder surface, for example. Surfaces of this type allow exact alignment of the angle position of the mass ring relative to the component to be balanced. The possibility of infinite adjustment may, however, make alignment of the mass ring difficult in individual cases. In particular, the mass ring may slip unintentionally prior to or during fastening. A preferred embodiment, which simplifies the positioning of the mass ring on the component, provides that on one of the components--component to be balanced and balancing body--to be fastened to one another in step c), a plurality of first indexing members distributed in peripheral direction is provided, and on the other of these components, at least one second indexing member is arranged, which allows the components to be fastened in form-locking manner relative to one another at least in the peripheral direction, and that in step c), each second indexing member is fastened to a first indexing member selected in dependence on the imbalance measured in step a). The first indexing members are preferably essentially axially extending grooves, which are, for example, arranged adjacent to one another on the component to be balanced and distributed in the peripheral direction at equal angle distances from one another, whereas the second indexing members are provided in the form of radially protruding projections, for example, which are moulded onto the longitudinal ends of the elongated balancing body. Grooves of this type may be provided without problem and at a low manufacturing cost in particular, when the component to be balanced has a sheet metal peripheral wall concentric to the axis of rotation, into which a wave structure is moulded radially. Such a wave structure can be a gear tooth system, which is provided for a starter pinion to engage in. The indexing members allow assembly of the mass ring in predetermined angle positions. Since the angle position of the indexing members need not necessarily assume the role of fastening the mass ring to the component for operation--additional fastening means, e.g. weld points or similar, may be provided for this purpose--the angle distance between the indexing members may be relatively small. In this way, a very exact alignment of the mass ring relative to the component is possible in spite of the indexing.
The balancing process described above may be used advantageously in particular in the case of a flywheel to be secured to the crankshaft of an internal combustion engine, since the mass moment of inertia of the flywheel can be additionally increased by the mass ring. This is of particular advantage in the case of dual-mass flywheels, if it is a matter of balancing the primary mass secured directly to the crankshaft of the internal combustion engine. The primary mass of the dual-mass flywheel, which is generally composed of two masses connected torsionally elastically to one another, is frequently provided in the form of a sheet metal moulded part and must be accommodated in a restricted structural space. The open mass ring used for balancing can be accommodated in areas of the structural space which could otherwise be utilised to increase the mass moment of inertia only at a comparatively high construction cost. A special provision may be that a starter tooth system to be moulded onto the primary mass may also be utilised for indexing the mass ring. The indexing possibility also permits those imbalance magnitudes and angle positions which do not match the index positions to be compensated with several mass rings. For standardisation of the mass rings, a set of mass rings with gaps of different sizes may be provided in particular, from which the mass rings necessary to compensate the imbalance are selected independently of the measured imbalance of the component.
The various features of novelty which characterise the invention are pointed out with particularity in the claims annexed to and forming part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an axial longitudinal section through one half of a dual-mass flywheel;
FIG. 2 shows a partial axial view of a primary mass of the dual-mass flywheel from FIG. 1;
FIG. 3 shows a partial representation of a first embodiment of the dual-mass flywheel from FIG. 1;
FIG. 4 shows a partial representation of a second embodiment of the dual-mass flywheel from FIG. 1, and
FIG. 5 shows a front view of the partial representation from FIG. 3.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 shows a schematic view of a dual-mass flywheel, in which the primary mass 1 is secured to a crankshaft 5 of an internal combustion engine of a motor vehicle by means of fasteners, e.g. screws 3. A secondary mass 11 is rotatably mounted equiaxial to the primary mass 1 with a bearing 9 on the primary mass 1, which rotates together with the crankshaft 5 around its axis of rotation 7. The secondary mass 11 is provided with a friction clutch in the conventional manner, the clutch housing being indicated at 13. The secondary mass 11 is coupled via a torsional vibration damper 15 to the primary mass 1 to be torsionally elastic.
In the dual-mass flywheel shown in FIG. 1, the primary mass 1 comprises a disc-shaped component 17, which has an essentially extending peripheral wall 19 on its outer periphery. A ring-disc-shaped cover 21 is connected to the peripheral wall 19 to define together with the disc-shaped component 17 an annular space 23, in which helical springs 25 of the torsional vibration damper 15 are accommodated. The helical springs 25 are coupled to the primary mass 1 via control plates 27 and to the secondary mass 11 via a disc portion 29.
A ring-shaped supplementary mass 33, which is firmly connected to a starter gear 31, is disposed in the area of the outer periphery of the primary mass 1. In the shown embodiment, the starter gear ring 31 together with the supplementary mass 33 are connected to the respective part by a common circumferential weld 34 provided between the disc-shaped component 17 and the cover to join these parts together. The supplementary mass 33 encloses the secondary mass 11 and extends axially beyond the secondary mass 11.
The supplementary mass 33 is provided with an axially accessible, circumferential recess 35 concentric to the axis of rotation 7, which is defined radially outwards by a cylindrical, inside peripheral surface 37 and towards the component 17 by a radially extending shoulder 39. An open mass ring 41, which centrically encloses the axis of rotation 7 over more than 180° and, as FIG. 2 shows, has a gap 45 between its longitudinal ends 3, is inserted into the recess 35. The radial and axial position of the mass ring 41 is determined by the peripheral surface 37 and the shoulder 39 of the recess 35, in which case the peripheral surface 37 fixes the effective distance of the mass ring 41 from the axis of rotation 7, and with it, the mass moment of inertia determined by the specific weight of the ring material and by the material cross-section. Calculated on the basis of the mass moment of inertia of the mass ring 41, the gap 45 in the mass ring 41 generates an imbalance, the magnitude of which is determined by the missing piece of material of the otherwise uniform mass ring 41. The size of the gap 45 is such that its dimensions are equal to the size of any imbalance of the primal mass 1 that may exist prior to installation of the mass ring 41. To compensate the imbalance of the primal mass 1, the mass ring 41 is inserted into the recess 35 and secured there in such a way that the centre of the gap 45 indicated by reference 47 coincides with the angle position of the imbalance of the primary mass 1. In this way, the gap 45 compensates the imbalance of the primary mass 1. It must be understood that the dimensions of the gap 45 of the mass ring 41 may also be such that it compensates the imbalance of the complete dual-mass flywheel, optionally including the clutch.
For balancing the primary mass 1, the magnitude and angle position of the imbalance are measured in the conventional way. Once the effective distance of the mass ring 41 and the specific weight of the material of the mass ring 41 is known, the size of the gap 45 together with the peripheral length of the mass ring 41 between its two longitudinal ends 43 can be calculated. A section with the calculated length may be cut from strand material and plastically moulded into a ring with a radius determined by the recess 35 to form the balancing body of the mass ring 41. The mass ring 41 thus prepared is inserted into the recess 35 at its gap 45 in such a way that the center 47 of the gap 45 matches the measured angle position of the imbalance of the primary mass 1. The mass ring 41 is fastened in this position, for example, by several weld points or similar. In an alternative embodiment of the balancing process, the material section cut from the strand material to correspond to the measured imbalance is not bent beforehand to form the open mass ring 41, but is plastically moulded while being inserted into the recess 35, and as insertion progresses, is fixed in the recess 35 section by section by means of weld points.
An advantage of the balancing process described above is that no further chip removal is required during the balancing process, i.e. no further metal chips are produced in this production stage. The additional mass ring 41 increases the mass moment of inertia. Since the peripheral surface 35 encloses and guides the mass ring 41 radially from the outside, a few fastening points less are sufficient for an operationally secure, permanent attachment.
As is indicated in FIG. 1 at reference 49, the ring-shaped recess concentric to the axis of rotation 7 provided to accommodate the open mass ring 41 can be arranged in such a way that it is defined by an outer peripheral surface 51 and a shoulder 53 protruding radially outwards. The recess 49 is at the same time axially accessible, but has the advantage that, according to the alternative embodiment of the balancing process explained above, the open mass ring can be wound directly on the cylindrical outside surface 51 and may optionally be secured at intervals by weld points. It is not necessary to shape the section of balancing body cut from the strand material into a ring beforehand. The peripheral length of the mass ring 41 is calculated as explained above with respect to recess 35; however, in this case, the effective distance of the mass ring is determined by the outer peripheral surface 51 of the recess 35 abutting the inside radius of the mass ring.
Variations of the dual-mass flywheel and the mass ring used for balancing it are described below. Components with the same effects are given the same references as in FIGS. 1 and 2 with an added letter to differentiate them therefrom. Reference is made to the description to FIGS. 1 and 2 for explanation of the structure and function of the dual-mass flywheel and of the process provided to balance it.
In the alternative embodiment of the primary mass 1a of the dual-mass flywheel shown in FIG. 3, the peripheral wall 19a of the disc-shaped component 17a to be secured to the crankshaft of an internal combustion engine, of the cover 21a and the starter gear ring 31a is connected to a component by the common circumferential weld 34a. A supplementary mass similar to the supplementary mass 33 in FIG. 1 is not shown, but may be provided. The peripheral wall 19a is provided on its front side axially facing the starter gear ring 31a with a recess or groove 49a, into which an open mass ring 41a is inserted to balance the primary mass 1a. The mass ring 41a, which is dimensioned and positioned as in the balancing process explained above, has a round cross-section. The groove 49a has a cross-section corresponding to the cross-section of the mass ring 41a and covers the mass ring 41a over a portion of the periphery of its material cross-section, i.e. radially from the inside and axially to the side. Since the groove 49a is not necessarily accessible axially for a pre-bent ring because of its position, the mass ring 41a is, for expedience, plastically moulded into the shape of a ring while being inserted into the groove 49a and successively fixed by weld points 55. It must be understood that the mass ring 41a may also have a rectangular or square material cross-section instead of its round cross-section. The mass ring 41 of the embodiment in FIGS. 1 and 2 may accordingly also have a round cross-section.
In the embodiments explained above, the open mass ring may be secured to the primary mass with its angle position infinitely adjusted during balancing. FIGS. 4 and 5 show a variation of the primary mass 1b of the dual-mass flywheel which permits indexed angle alignment of the open mass ring 41b used for the balancing process. The peripheral wall 19b of the disc portion 17b to be secured to the crankshaft centrically to the axis of rotations 7b is extended in axial direction beyond the cover 21b and is provided in this area with axially extending teeth 57 to form the starter gear ring 31b. The teeth 57 are plastically moulded and stamped into the sheet metal material of the peripheral wall 19b and form axially extending grooves 59 on the radially inner side located radially opposite in the angle grid of the teeth 57. The inner periphery of the starter gear ring 31b formed by the extension to the peripheral wall 19b forms an inner peripheral surface, against which the open mass ring 41b abuts radially. The longitudinal ends 43b of the mass ring 41b are provided with lugs 61 protruding radially outwards, each of which is received in one of the grooves 59 formed on the rear of the teeth 57. The lugs 61 assure that the mass ring 41b is indexed and its angle position fixed relative to the primary mass 1b, and may be moulded on, for example, by caulking the longitudinal ends 43b after the balancing body forming the mass ring 41b has been cut from the strand material. As FIG. 5 shows, the mass ring 41b may be secured to the peripheral wall 19b by a few weld points 63, in particular in the area of the longitudinal ends 43b.
To balance the primary mass 1b, its imbalance is firstly measured in order to determine the size of the gap 45b of the mass ring 41b fixed in effective radius by the inner periphery of the starter gear ring 31b. After the section of strand material forming the balancing body has been cut into lengths, the lugs 61 are moulded on the longitudinal ends and the material is bent to form the open mass ring. The mass ring 41b is then indexed, inserted through grooves 59 and, welded or caulked.
The weight steps, which are determined by the grid dimension of the grooves 59, of the gap 45b and of the position of the gap 45b relative to the primary mass 1b are relatively small to thus ensure a sufficiently high degree of balancing precision. As indicated in FIGS. 4 and 5, two or several mass rings 41b' may optionally be used instead of a single mass ring 41b, whereby although their gaps are indexed, they are arranged offset at an angle to one another, so that the resulting number of gaps compensates the imbalance of the primary mass 1b.
In the embodiment in FIG. 5, lugs are moulded onto both longitudinal ends 43b. In this embodiment, the peripheral width of the gap 45b is an integral multiple of the peripheral distance between two adjacent grooves 59. Intermediate lengths of the gaps may be adjusted, if only one lug 61 is provided on one of the longitudinal ends 43b.
Embodiments, in which the open mass ring encloses the peripheral wall 19b from the outside and engages with lugs between adjacent teeth of the starter gear ring at a point not covered by the starter pinion, are not shown in further detail. Moreover, it goes without saying that in place of a mass ring produced from strand material, the mass ring is optionally provided in the form of a shaft ring in its peripheral direction, whereas one or several projections are provided on the primary mass for indexing.
It must be understood that the balancing processes described above are not only applicable to a dual-mass flywheel, but may be applied, in principle, to any component arranged concentrically to the axis of rotation. The balancing process may be used advantageously in particular when no further chip removal may or must be undertaken, or when the increase in the moment of mass inertia is not harmful or is even desirable.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles. | For balancing a rotating component, in particular a component arranged in the drive train of a motor vehicle such as a flywheel, for example, it is proposed that an incomplete mass ring is attached to the component, in which the gap is dimensioned so that it corresponds to the magnitude of the imbalance measured at the component and is arranged in the angle position of the measured imbalance. | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to a warning system that will automatically activate a vehicle's warning lights for alerting a driver of a following vehicle when a leading vehicle is decelerating by way of solely downshifting. This system is adapted to be utilized with conventional vehicle warning lighting systems.
BACKGROUND OF THE INVENTION
[0002] Vehicles are normally equipped with conventional brake lights that are turned on upon activation of the brake pedal when slowing down or stopping the vehicle. A driver in a following vehicle will be alerted accordingly. However, the driver of a following vehicle will generally receive no such warning if the leading vehicle is decelerating by way of solely downshifting.
[0003] The present invention contemplates the automatic activation of the vehicle's warning lights upon deceleration by downshifting. Thus the following vehicle will see the warning lights when the leading vehicle decelerates by downshifting and be able to react more quickly thereby avoiding a collision which might otherwise occur.
[0004] Each year, in the United States alone, there are approximately twelve million auto accidents resulting in more than forty thousand deaths and two million injuries. It is estimated that approximately half are rear-end type collisions. If the invention disclosed herein could reduce these figures by only five percent, the human and financial benefits would be enormous.
[0005] Modern highway systems in or near metropolitan areas are designated to accommodate large volumes of high speed vehicular traffic. It appears, however, that many commuters who use these highways on a regular basis are so familiar with the layout of the roadway that they become complacent and follow too closely or fail to use proper caution under circumstances of reduced visibility. This has resulted in an alarming increase in the frequency and severity of chain reaction collisions both in this country and abroad.
[0006] The Downshifting Warning System according to the present invention, by providing the earliest possible indication of deceleration, would greatly diminish the frequency and severity of such events.
DESCRIPTION OF THE PRIOR ART
[0007] The use of brake lights is known in the prior art. More specifically, brake lights heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements. Known prior art brake lights include U.S. Pat. No. 4,922,225; U.S. Pat. No. 4,107,647; U.S. Pat. No. 4,575,782; U.S. Pat. No. 4,806,782; U.S. Pat. No. 4,034,338; and U.S. Pat. No. Des. 332,234.
[0008] Various systems exist for controlling vehicle brake lights to indicate braking situations to following vehicles. The conventional system is a mechanical switch that closes on brake activation to energize the brake lights. Then, upon release of the brake switch, the switch opens and the lights extinguish.
[0009] U.S. Pat. No. 4,990,887 discloses a brake light arrangement that provides a time delay in the extinguishing of lighted brake lights. Thus, when the lights are energized they will continue to be illuminated for a predetermined period of time.
[0010] U.S. Pat. No. 5,139,115 discloses a system in which the brake lights are lighted in the usual manner under normal braking conditions but flash when the anti-lock braking system of the vehicle is activated.
[0011] U.S. Pat. No. 6,023,221 discloses a system in which the hazard lights are lighted during emergency situations involving hard braking and rapid deceleration of the vehicle.
[0012] U.S. Pat. Nos. 4,105,994; 4,158,833; and 5,852,399 each disclose a system comprising an open switch located on a standard transmissions gear shift module which activates the vehicle's brake lights when the transmission's gear shift lever engages the receiving gear module, thus closing the circuit.
[0013] In these respects, the Downshifting Warning System according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus for alerting a driver of a following vehicle when a leading vehicle is decelerating by way of solely downshifting.
BRIEF DESCRIPTION OF DRAWINGS
[0014] [0014]FIG. 1 is a schematic diagram of the downshifting warning system according to the present invention.
[0015] [0015]FIG. 2 is a schematic diagram of the microcontroller “AND” switch of FIG. 1.
[0016] [0016]FIG. 3 is a schematic diagram of an alternative embodiment of the downshifting warning system according to the present invention.
[0017] [0017]FIG. 4 is a flow diagram illustrating the operation of the electronic unit in accordance with the principles of this invention.
[0018] [0018]FIG. 5 is a flow diagram illustrating the operation of the electronic unit in accordance with the principles of an alternative embodiment of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] Referring now to FIG. 1, the electrical components of the invention are indicated at 10 . The vehicle power source 12 that is available only when the ignition key 1 is on supplies current to a voltage regulator 5 . The power source also continuously supplies voltage to the manual brake pedal switch 15 which is activated when the vehicle's brake pedal is engaged.
[0020] The voltage regulator reduces vehicle electrical system voltage to the required input level for the digital circuitry which is normally +5 volts for commercially available components. In the event that application specific integrated circuitry to operate on the vehicle electrical system voltage is used, the voltage regulator would not be required.
[0021] The digital accelerometer's 40 integrated electronics chip measures changes in capacitance caused by acceleration and converts those changes into a digital pulse output. The digital accelerometer 40 usually consists of a sensing element and an electronic chip assembled in an integrated unit. The sensing element consists of machined microstructures that respond to acceleration by changing their capacitances. In common and conventional accelerometer designs, the vehicle's acceleration produces a moment about an axis which allows a suspended plate to rotate, constrained only by the spring constant of the suspended plate's connection to an axis. The suspended plate and a corresponding fixed plate are positioned to form air-gap variable capacitors with a common connection thus creating a fully active capacitance bridge. The average distance between the suspended plate and the fixed plate decreases due to the moment caused by a change in vehicular acceleration, thus increasing its capacitance. Conversely, the average distance between the suspended plate and the fixed plate increases due to the moment caused by an opposite change in vehicular acceleration, thus decreasing its capacitance. The integrated chip converts the small capacitance changes between the sensing elements into a useful electrical signal. These electronics must be closely coupled to the sensing elements to accurately measure the minuscule acceleration-caused changes in capacitance that occur in the presence of much larger stray capacitances. The digital accelerometer 40 generates a pulse stream whose frequency (or, more precisely, pulse density) is proportional to acceleration. Such digital acceleration units are commercially available devices and may be of the type sold by Silicon Designs, Inc. as Model 1010, Analog Devices ADXL250, Quatech's QTC-350, or Analog Devices ADXL 105. The digital accelerometer's 40 input signal may be derived in any known way providing it has a frequency proportional to the vehicle's acceleration. In the event that the vehicle utilizes an existing digital accelerometer as set out above, the digital accelerometer 40 of the present invention would not be required. The output signal from the existing accelerometer could be coupled with the present invention, thus eliminating the requirement for an additional duplicative unit. Additionally, an analog accelerometer can be utilized with the addition of a digitizer to convert the analog output signal to a digital one. Such analog accelerometer generates a differential voltage output proportional to acceleration whose output could easily be converted with the addition of an in series digitizer.
[0022] A digital tachometer 30 includes a circuit for receiving a pick-up pulse having a frequency related to the rotation speed of the engine and outputting a wave shaped pick-up pulse. The tachometer comprises a circuit means for receiving a pick-up pulse, the frequency of which is related to the rotational speed of the engine and for outputting a wave shaped pick-up value. A multiplier/divider is often an integral component of a tachometer, utilized for receiving the pick-up pulses and divides them by the number of pulses per revolution to provide pulses indicative of engine rotational speed. The multiplier/divider circuit provides a d.c. output reference voltage indicative of speed in addition to the speed pulses which are each of equal duration and voltage but have varying intervals depending upon the speed of the engine. The digital tachometer 30 generates pulses resulting from rotation of the vehicle's shaft, counted over a predetermined time interval established by the microcontroller's clock generator. The larger the number of pulses counted within a time interval, the higher the speed of the shaft. Thus, the count of pulses within the time interval is proportional to the shaft speed.
[0023] The digital tachometer 30 utilized in this invention functions to accurately measure the speed of rotation of the vehicle's crankshaft, providing it is possible to derive a synchronous electrical signal representing a fraction of a revolution, a whole revolution, or a predetermined number of revolutions. Thus the purpose of the digital tachometer 30 of the present invention is for measuring the speed of rotation of a rotating device, which can provide an output signal which has great accuracy due to rapid updating as the speed of rotation of the rotating device changes.
[0024] The speed of rotation of a rotating device may be determined by various means including counting pulses derived from an electrical signal produced by means sensitive to the speed of rotation of the engine's crankshaft the frequency of which sensor signal is a function of the speed of rotation of the engine's crankshaft, characterized by the fact that it comprises means for deriving from the said sensor signal, a first electrical signal, comprising a train of pulses the pulse repetition frequency of which is variable and directly related to the instantaneous frequency of the said sensor signal by a predetermined scale factor, counting means fed with the said first signal, processing means fed with the said first signal and operable to produce a second signal in the form of a train of pulses the frequency of which a predetermined given number of pulses would occur in the immediately preceding interval between two successive pulses of the first signal, interpolation means fed with the said second signal and operative to count the pulses thereof, a time base circuit which generates a signal controlling the operation of the said counting means such that these count the pulses of the said first signal only during successive counting intervals each of predetermined duration, memory means which are fed with a signal representing the content of the counting means accumulated during the last complete counting interval together with the content of the interpolation means accumulated between the last pulse of the said first signal and the end of the counting interval, and output means for generating a signal corresponding to changes in the vehicle's crankshaft change in rate of rotation.
[0025] The digital tachometer's 30 input signal may be derived in any known way providing it has a frequency proportional to the speed of rotation it is required to measure. It is understood that the digital tachometer according to the present invention may operate from a capacitor discharge ignition or other suitable signal source, such as a magnetic pick-up. An electrical signal representing the speed of rotation of an internal combustion engine can be derived simply and directly, by connecting the lead to the contact breaker of the coil ignition: alternatively the signal can be obtained from a detector such as a coil wire wound around a spark-plug lead. Other known means, such as electric, magnetic, or electromagnet detectors may be used, to obtain a periodic input signal on the input lead, with a frequency proportional to the speed of rotation it is desired to measure. Where the speed of rotation of an internal combustion engine is detected by sensing the electrical surge voltages at the contact breaker or in a spark plug high tension lead, due allowance must be made for the relationship between the frequency of the signal and the speed of rotation of the engine.
[0026] Such digital tachometer units are commercially available devices. In the event that the vehicle utilizes an existing digital tachometer as set out above, the digital accelerometer of the present invention would not be required.
[0027] A microcontroller 20 includes a clock generator which is activated upon closure of the ignition key switch 1 . The clock generator comprises a highly stable oscillator, suitably of the quartz type, and a plurality of counting decades which, by means of known output circuits, provides various output signals of different frequencies. The clock signal can also operate to synchronize the tachometer and accelerometer's input signals. The clock generator's signal is fed to the digital tachometer 30 unit which compensates for the relation between the frequency of the signal and the actual number of revolutions per unit time of the rotating device being measured. The clock signal is transmitted to the digital accelerometer 40 and the number of generated per clock cycle represents both the amount and direction of acceleration of the vehicle. That is, based on rated measuring capacity of a single output accelerometer 40 , a zero pulse rate would indicate full scale negative acceleration, and a maximum pulse rate would indicate full scale positive acceleration. A mid-range value would reflect zero acceleration. If utilizing a multiple output accelerometer, a zero pulse rate would reflect zero acceleration and changes in pulse rates would be indicative of changes in acceleration.
[0028] A clock signal is also transmitted to the digital tachometer 30 and the number of pulses generated per clock cycle represents the amount rotation of the vehicle engine crankshaft. The rate of change in the speed of rotation of the vehicle's engine crankshaft per predetermined unit of time is utilized to determine the rate of change or rotations of the crankshaft.
[0029] As shown in FIG. 2, the microcontroller 20 is programmed to transmit an “on” signal when both an accumulated pulse count indicative of a predetermined threshold rate of deceleration is recognized at the same time as an accumulated pulse count exceeding a predetermined threshold rate of change in speed of rotation of the vehicle engine crankshaft is recognized. The microcontroller 20 comprises an “AND” switch 28 requiring both predetermined threshold signals from the tachometer 30 and the accelerometer 40 . Assuming that the tachometer indicated change in pulse rate (+) 24 exceeds a predetermined threshold rate of crankshaft rotations and the accelerometer indicates a pulse rate (−) 22 indicative of deceleration exceeding a predetermined threshold rate of deceleration, then both signals would activate and complete the “AND” switch, thus activating the vehicle's warning lights. It is understood that if a negative analog signal or negative digital signal is generated as an output signal from the accelerometer 22 , a signal inverter 26 positioned in series to reverse the negative signal, thus making it a positive one, to activate the “AND” switch 28 , thus sending a signal to illuminate the vehicle's warning lights. The use of the inverter circuit 26 assumes the accelerometer used has a negative signal for deceleration and a positive signal output for acceleration. If the accelerometer has two positive outputs, one for deceleration and one for acceleration, the inverter can be eliminated.
[0030] As seen in FIG. 3, an alternative embodiment of the present invention eliminates the additional input of a tachometer 30 . Therefore, the microcontroller's 20 clock generator would only generate a clock signal for transmital to the digital accelerometer 40 and the number of pulses generated per clock cycle represents both the amount and direction of acceleration of the vehicle. That is, based on rated measuring capacity of the accelerometer 40 , a zero pulse rate would indicate full scale negative acceleration, and a maximum pulse rate would indicate full scale positive acceleration. A mid-range value would reflect zero acceleration. The digital accelerometer 40 generates a pulse stream whose frequency (or, more precisely, pulse density) is proportional to acceleration.
[0031] [0031]FIG. 4 depicts a flow diagram illustrating the operation of the present invention in accordance with the principles of this invention. As seen in this diagram, the manual brake pedal switch 15 acts independent of the present invention, thus preventing the downshifting warning system from interfering with the driver's manual activation of the brake lights. In this embodiment, the vehicle's acceleration is compared to a predetermined threshold rate of acceleration “A.” If the vehicle's acceleration equals or exceeds this predetermined rate of acceleration, then the vehicle engine's crankshaft rate of rotation will be compared to a predetermined threshold of rate of rotation “R.” If the vehicle's acceleration exceeds the predetermined threshold rate of acceleration “A” and vehicle engine's crankshaft rate of rotation exceeds a predetermined threshold rate of rotation “R” then a signal will be transmitted to activate the vehicle's warning lights. Although the measure of acceleration and crankshaft rotations are in series and the measure of acceleration occurs first, it is understood that the measure of crankshaft rotations per minute can be measured first. Additionally, this circuit or flow diagram can be designed as a parallel circuit without the tachometer and accelerometer in a series configuration.
[0032] [0032]FIG. 5 depicts a flow diagram illustrating the operation of an alternate embodiment of the present invention in accordance with the principles of this invention. As seen in this diagram, the manual brake pedal switch 15 acts independent of the present invention, thus preventing the downshifting warning system from interfering with the driver's manual activation of the brake lights. In this embodiment, the vehicle's acceleration is compared to a predetermined threshold rate of acceleration “A.” If the vehicle's acceleration equals or exceeds this predetermined rate of acceleration then a signal will be transmitted to activate the vehicle's warning lights.
[0033] Specific thresholds of vehicle deceleration and rate of rotation of the vehicle engine crankshaft and activation are predetermined. An automatic cancellation feature may also be programmed into the microcontroller. It is understood that the microcontroller can be manually adjusted according to the particular vehicle and/or driver.
[0034] The manual brake pedal switch allows vehicle electrical system voltage to be connected directly to the brake lights. This arrangement allows the vehicle operator to activated the brake lights manually via the brake pedal regardless of the present invention.
[0035] Although the invention has been described with respect to controlling the standard brake lights on an automobile having a manual transmission, it is understood that it may control any vehicle light system for warning following vehicles. Thus the term brake lights as used herein includes any vehicle mounted lights for alerting or warning other vehicles of deceleration solely from downshifting of a manual transmission.
[0036] The term acceleration as used herein includes negative acceleration or deceleration. The term frequency as used herein pertains to pulses per interval of time.
[0037] Additionally, diodes, resistors and/or other electrical components may be utilized in conjunction with the present invention for improving the routing and/or efficiency of the electrical circuit and regulating electrical system voltage.
[0038] Having thus described the invention with particular reference to the preferred forms thereof it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It should also be noted that while the foregoing description pertains to a digital system, the invention can be constructed on either a digital or analog circuit basis. | The present invention relates to a vehicle warning lighting system having a novel automatic warning light activation system utilized with a conventional vehicle brake lighting system. The downshifting deceleration safety system, including and accelerometer and an optional tachometer, will automatically activate the conventional vehicle brake lighting system under conditions of downshifting causing deceleration. The conventional vehicle brake lighting system includes a battery member being a power source connected through a brake pedal switch to brake light members. Depression of a brake pedal closes the brake pedal switch to energize the brake light members in a conventional manner. | 1 |
BACKGROUND OF THE INVENTION
The present invention generally relates to distortion eliminating circuits for eliminating distortion from signals and particularly to a circuit for eliminating a harmonic distortion from a high frequency information signal reproduced from an information recording disk.
The assignee of the present invention proposed previously in the U.S. Pat. application No. 873,407, U.S. Pat. No. 4,803,677, an information recording disk on which an information signal such as a video signal is recorded by an optical beam in a form of intermittent row of pits along a recording track and a recording and reproducing apparatus for recording and reproducing the information signal on and from such a disk by means of the optical beam. When recording a video signal on the disk, a high frequency video signal comprising a frequency converted carrier chrominance signal and a frequency modulated luminance signal is produced in the recording and reproducing apparatus, and this high frequency video signal is used to drive a laser diode. The laser diode produces a high power optical beam for recording responsive to the driving by the high frequency video signal and the recording of the high frequency video signal is made on the surface of the optical disk as a row of pits by evaporating a portion of the optical disk by the optical beam.
When to reproduce the video signal from the disk, a low power optical beam or optical probe is produced by the laser diode and the optical probe scans the surface of the optical disk. On the basis of the reflection of the optical probe from the optical disk, the high frequency video signal is reproduced, and this high frequency video signal is separated into the frequency converted carrier chrominance signal and the frequency modulated luminance signal by filtering. The frequency converted carrier chrominance signal thus reproduced is processed in a color singal reproducing circuit while the frequency modulated luminance signal is first converted into a series of rectangular pulse signals having a pulse width corresponding to the frequency of the frequency modulated luminance signal and the pulse signals thus produced are then processed in a luminance signal demodulating circuit for recovering the original luminance signal.
As described previously, the information is recorded on the surface of the optical disk by irradiating the high power optical beam so as to evaporate a portion of the optical disk. Thus, the row of pits carrying the information is formed as a result of evaporation. The row of pits defines the track on the disk and the pit has a length in the direction of the track which changes responsive to the waveform of the high frequency video signal to be recorded such that the length of the pit is long when a relatively low frequency video signal is recorded and that the length of the pit is short when a relatively high frequency video signal is recorded. Further, the row of pits is formed with such a format that a length of one pit and a separation between that pit and a neighboring pit are identical. In order to achieve such a pattern of the pits, the high frequency signal which drives the laser diode comprises a series of recording pulse signals each of which consisting of a positive pulse portion and a negative pulse portion wherein the duration of the positive pulse portion and the duration of the negative pulse portion are made identical. In the description hereinafter, a signal having such a waveform will be referred to as a signal having a 50% duty cycle. It should be noted that the duration of the each pulse signal constituting the high frequency video signal is changed but the ratio in the duration of the positive pulse portion and the negative pulse portion in each pulse signal is not changed. In other words, the duty cycle of the high frequency signal which drives the laser diode is maintained at 50%. When the high frequency video signal is reproduced on the basis of the pattern of such pits formed properly on the surface of the disk, the reproduced high frequency signal reproduced by scanning the pits by the optical beam has a sinusoidal wave form. The reproduced high frequency signal having the sinusoidal wave form is then supplied to a wave processing circuit comprising a comparator and the original high frequency video signal comprising the rectangular pulse signals is recovered.
It should be noted, on the other hand, that the length of the pit on the disk is changed responsive to the power of the optical beam. Thus, the length of the pit becomes smaller than the separation between the pits when the recording is made with an optical beam having an insufficient power and the length of the pit becomes larger than the separation between the pits when the recording is made with an optical beam having an excessive power. It should be noted that when the length of the pit and the separation between an adjacent pair of pits including the aforesaid pit in the pair is not identical, the waveform of the reproduced high frequency signal is not sinusoidal but contains a harmonic distortion. Thus, when the frequency modulated luminance signal is separated from the reproduced high frequency video singal containing the harmonic distortion, the harmonic distortion is transferred to the frequency modulated luminance signal in a form of a distortion component and such a distortion component cannot be removed even if the frequency modulated luminance signal is converted to a row of rectangular pulse signals by passing through the wave processing circuit comprising the comparator. In other words, the duty cycle of the frequency modulated luminance signal thus processed is different from 50%. Thus, when the luminance signal is recovered from the row of rectangular signals representing the frequency modulated luminance signal, the luminance signal thus obtained is not identical to the original luminance signal and there occurs a carrier leak in which a high frequency carrier produced as a result of distortion is superposed on the reproduced picture. As a result, fine stripes appear in the reproduced picture and the quality of the reproduced picture is deteriorated. Further, such a reproduced luminance signal reproduced from the frequency modulated luminance signal containing the harmonic distortion affects the operation of a non-linear emphasis circuit used in the recording and reproducing circuit for removal of the noise components and the quality of the reproduced picture is further deteriorated.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to provide a novel and useful distortion eliminating circuit for eliminating distortion form a reproduced frequency modulated signal reproduced from an optical information recording disk wherein the aforementioned problems are eliminated.
Another and more specific object of the present invention is to provide a distortion eliminating circuit comprising wave processing means supplied with an input frequency modulated signal and for producing a series of pulses on the basis of comparison of the frequency modulated signal with a reference voltage, a smoothing means for smoothing the series of pulses from the wave processing means and for obtaining a d.c. (direct current) voltage level indicating an average voltage of the pulses from the comparator means, detection means for detecting a distortion component in the frequency modulated signal and for obtaining a d.c. voltage representing the magnitude of said distortion component, and mixing means for adding said d.c. voltage corresponding to the distortion component to said reproduced frequency modulated signal so as to form a compensated frequency modulated signal having a level adjusted as a result of addition of the distortion components and for feeding the compensated frequency modulated signal back to said comparator means. According to the present invention, the level of the reproduced frequency modulated signal is shifted relative to the reference voltage used in the wave processing means so that effect of the harmonic distortion is eliminated from the series of pulses outputted from the wave processing means. Thus, a series of pulses having a duty cycle of 50% and from which the effect of the harmonic distortion is eliminated can be obtained in correspondence to the input frequency modulated signal even if the input frequency modulated signal contains the harmonic distortion.
Another object of the present invention is to provide a distortion eliminating circuit for eliminating a harmonic distortion from an input high frequency video signal comprising a frequency converted carrier chrominance signal and a frequency modulated luminance signal. According to the present invention, the effect of the harmonic distortion in the frequency modulated luminance signal is eliminated. As a result, the carrier leak on the reproduced picture is suppressed and the deteriorating effect to the non-linear deemphasis circuit used for reproduction of the luminance signal is avoided. Thus, the distortion eliminating circuit of the present invention prevents the deterioration of the quality of the reproduced picture.
Another object of the present invention is to provide a distortion eliminating circuit for eliminating a harmonic distortion from a high frequency video signal reproduced from an information recording disk on which an information is recorded by means of an optical beam in a form of a row of pits. According to the present invention, the effect of the higher order distortion caused as a result of the difference between the length of the pit and the distance between a pair of pits is eliminated and the deterioration in the quality of the reproduced picture is prevented.
Still other object of the present invention is to provide a distortion eliminating circuit comprising comparator means supplied with an input frequency modulated signal and for producing a series of pulses having a predetermined peak to peak level responsive to the result of comparison of the input frequency modulated signal with a predetermined reference voltage, smoothing means for smoothing said series of output pulses and for producing a d.c. voltage representing an average level of the series of pulses, said smoothing means comprising a first reference voltage source for producing a first reference voltage for clamping the base level of the series of pulses, a clamp circuit supplied with said first reference voltage and clamping the base level of the series of pulses outputted from the comparator means at said first reference voltage, and a low pass filter for extracting a d.c. component from output pulses outputted from the clamp circuit, and detection means for producing an output d.c. voltage corresponding to the harmonic distortion, said detection means comprising a second reference voltage source for producing a second reference voltage representing an average voltage level of pulses having a 50% duty cycle, a differential amplifier for subtracting the d.c. component from said smoothing means from said second reference voltage, and an inverter for inverting an output signal from said differential amplifier. According to the present invention, it is possible to obtain an output signal having a 50% duty cycle and from which the effect of the higher order distortion is eliminated.
Still another object of the present invention is to provide a distortion eliminating circuit comprising comparator means supplied with an input frequency modulated signal for producing a series of pulses by comparing the level of input frequency modulated signal with a predetermined threshold voltage and further for producing a series of inverted output pulses which are inversion of said series of pulses, smoothing means including a first low pass filter for smoothing the pulses from the comparator means and a second low pass filter for smoothing the inverted output pulses from the comparator means, and detection means including a differential amplifier for amplifying the difference between output signals from the first and second low pass filters and an amplifier for amplifying the output signal of the differential amplifier. According to the present invention, the number of circuits constituting the distortion eliminating circuit can be reduced.
Still other objects and further features of the present invention will become apparent from the following detailed description for preferred embodiments when read in conjunction with attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a part of an information reproducing apparatus to which the distortion eliminating circuit of the present invention is applicable;
FIG. 2 is a block diagram showing a first embodiment of the distortion eliminating circuit of the present invention;
FIG. 3, consisting of (A)-(D), is a waveform chart showing signal waveforms appearing at various parts of the circuit of FIG. 2; and
FIG. 4 is a block diagram showing a second embodiment of the distortion eliminating circuit of the present invention.
DETAILED DESCRIPTION
FIG. 1 shows a part of a reproducing apparatus for reproducing an information signal recorded on an information recording disk (not shown) to which the distortion eliminating circuit of the present invention is applied. Referring to the drawing, a reproduced high frequency information signal reproduced as a result of reflection of an optical beam at the surface of the information recording disk is applied to an input terminal 10. When the information signal recorded on the recording disk is a video signal, the reproduced high frequency information signal comprises a frequency converted carrier chrominance signal and a frequency modulated luminance signal. This input high frequency video signal applied to the input terminal 10 is then passed through a low pass filter 12 where a reproduced frequency converted carrier chrominance signal is obtained and to a high pass filter 13 where a reproduced frequency modulated luminance signal is separated from the input high frequency video signal. The frequency converted carrier chrominance signal obtained by the low pass filter 12 is supplied to an output terminal 14 for further processing in a color signal processor (not shown) of the reproducing apparatus. On the other hand, the frequency modulated luminance signal obtained by the high pass filter 13 is supplied to a comparator 16 after passing through the distortion eliminating circuit 15 of the present invention. The comparator 16 compares the level of the frequency modulated luminance signal supplied thereto with a predetermined threshold voltage, and produces an output pulse only when the level of the input frequency modulated luminance signal exceeds the threshold voltage. As a result, a series of pulses having a pulse width which changes responsive to the frequency of the frequency modulated luminance signal is produced in correspondence to the waveform of the frequency modulated luminance signal The pulses thus obtained is supplied to an output terminal 17 from which the pulses are supplied to a luminance signal demodulating system (not shown) of the reproducing apparatus. Further, the pulses are looped back to the distortion eliminating circuit 15 of the present invention. As will be described later, the distortion eliminating circuit 15 adjusts the overall level of the pulses looped back from the comparator 16 and produces a compensated pulses having a level adjusted such that the effect of the harmonic distortion is eliminated from the pulses obtained by the comparator 16 when the compensated pulses thus produced by the distortion eliminating circuit 15 are looped back to the comparator 16.
FIG. 2 is a block diagram showing a first embodiment of the distortion eliminating circuit of the present invention. Referring to the drawing, the reproduced frequency modulated luminance signal including a harmonic distortion is supplied from the low pass filter 13 to an input terminal 20. The signal is then supplied to the comparator 16 after passing through a subtractor 21. The comparator 16 compares the supplied frequency modulated luminance signal with a predetermined reference voltage V TH and produces a series of pulses having a peak-to-peak voltage X responsive to the portion of the waveform of the frequency modulated luminance signal having a level which exceeds said predetermined reference voltage V TH . The pulses thus produced is supplied to the output terminal 17 on one hand and to a clamp circuit 23 on the other hand. The clamp circuit 23 adjusts the pulses such that the base level or low level state of the pulses is set to another predetermined fixed reference voltage Y which is supplied thereto from a reference voltage source 24, and supplies a series of output pulses having a base level thus fixed to the reference voltage Y. The pulses thus processed in the clamp circuit 23 is then supplied to a low pass filter 25 where a d.c. component representing the average level of the pulses is extracted from the pulses by filtering. In other words, the low pass filter 25 filters out oscillating component from the pulses. The d.c. component thus obtained has a level corresponding to the average level of the pulses, and this average level is changed depending on the duty cycle of the pulses. In other words, the d.c. component thus obtained contains a d.c. distortion component α corresponding to the harmonic distortion produced as a result of the deviation in the pattern of pits on the surface of the recording disk. Thus, the level of the d.c. component outputted from the low pass filter 25 is represented as Y+X/2+α. The d.c. component obtained by the low pass filter 25 is then supplied to a differential amplifier 26 where it is subtracted from a still another predetermined reference voltage Y+X/2 given by a reference voltage source 27, and the d.c. distortion component α corresponding to the harmonic distortion is extracted from the d.c. component obtained by the low pass filter 25. It should be noted that the d.c. distortion component which is actually obtained by the subtraction is -α and the sign of the component is inverted. This sign of this d.c. distortion component α is inverted in a phase inverting amplifier 28. The phase inverting amplifier 28 further amplifies the magnitude of the d.c. distortion component α such that the effect of the d.c. distortion component is properly cancelled out in the processing in the circuit 15. For this purpose, the amplifier 18 is supplied with a d.c. signal for adjustment of its amplification factor from a rheostat VR. The d.c. distortion component α obtained by the phase inverter 28 is supplied to the subtractor 21 which is mentioned previously where it is subtracted from the frequency modulated luminance signal. Thus, the level of the reproduced frequency modulated luminance signal passed through the subtractor 21 is adjusted and the frequency modulated luminance signal thus processed is supplied to the comparator 16 again. As a result, the average level of the pulses produced by the comparator 16 responsive to the frequency modulated luminance signal thus processed is set to Y+X/2 and the effect of the harmonic distortion in the reproduced frequency modulated luminance signal is eliminated.
Next, the operation of the distortion eliminating circuit of the present invention will be described with reference to FIGS. 3(A)-(D). FIG. 3(A) shows an example of the waveform of a frequency modulated luminance signal corresponding to a pattern of pits on the disk in which the length of the pits is significantly smaller than the separation between the pits. It can be seen that the reproduced frequency modulated luminance signal contains a significant amount of harmonic distortion. The frequency modulated luminance signal in FIG. 3(A) is supplied to the comparator 16 where it is converted to the pulses by comparison of the level of the frequency modulated luminance signal with the aforementioned predetermined threshold voltage V TH . It should be noted that the level of the voltage V TH is fixed. At the beginning, the level of the input frequency modulated luminance signal supplied to the comparator 16 is not adjusted by the subtractor 21. In other words, at the beginning of operation of the distortion eliminating circuit 15, the level V TH used in the comparator 16 is coincident to one half of the peak-to-peak level of the input frequency modulated luminance signal in correspondence to an ideal case shown in FIG. 3(B). It should be noted that the level V TH shown in FIG. 3(A) by a broken line is not the level V TH used in the comparator 16 at the beginning of operation of the distortion eliminating circuit 15 of the present invention. This one half level of the peak-to-peak level of the input frequency modulated luminance signal is indicated in FIGS. 3(A)-(C) by VAV. If the comparator 16 which is operating with the threshold level V TH which in turn is coincident to the level VAV is used for processing of the frequency modulated luminance signal shown in FIG. 3(A), it is obvious that the duty cycle of the obtained pulses becomes significantly smaller than 50%. As the level of the d.c. component obtained by filtering the pulses having such a low duty cycle by the low pass filter 25 is correspondingly smaller as a result of the harmonic distortion as already described, the overall level of the frequency modulated luminance signals outputted from the subtractor 21 is raised by an amount equal to the d.c. distortion component α by the subtractor 21, and the threshold level V TH is lowered relative to the VAV level of the frequency modulated luminance signal. FIG. 3(A) shows the wave form of the frequency modulated luminance signal in a state that the VAV level, and accordingly the overall level, of the frequency modulated luminance signal is raised relative to the level V TH . When such a frequency modulated luminance signal having a raised VAV level is processed in the comparator 16 operating with the fixed threshold level V TH shown in FIG. 3(A), one can obtain the pulses corresponding to the frequency modulated luminance signal having a duty cycle of 50% as shown in FIG. 3(D).
FIG. 3(B) shows the ideal case in which the length of the pits and the separation between the pits are identical. In this case, the level VAV coincides with the level V TH and the d.c. distortion component α is zero. Thus, the level adjustment in the subtractor 21 is not performed. In other words, the frequency modulated luminance signal supplied to the subtractor 21 is fed to the comparator 16 as it is, and a series of pulses having the duty cycle of 50% is obtained as shown in FIG. 3(D).
FIG. 3(C) shows a case in which the length of the individual pits is smaller than the separation between the pits and the frequency modulated luminance signal supplied to the input terminal 20 has the harmonic distortion. In this case, the duty cycle of the output pulses become larger than 50% at the beginning of the operation of the distortion eliminating circuit 15. As a result of the increased duty cycle of the pulses, the level of the frequency modulated luminance signal is decreased by the subtractor 21 and the threshold level V TH used in the comparator 16 is raised relative to the VAV level as shown by a broken line in FIG. 3(C). As a result, the output rectangular wave has a shape as shown in FIG. 3(D) and the 50% duty cycle is achieved.
Thus, the distortion eliminating circuit 15 of the present invention produces a series of pulses responsive to the input frequency modulated luminance signal from which the effect of the harmonic distortion is eliminated. Thus, the deteriorating effect on the reproduced picture due to the carrier leak is eliminated and the quality of the reproduced picture is improved.
FIG. 4 shows a circuit diagram of a second embodiment of the distortion eliminating circuit of the present invention. Referring to the drawing, those parts constructed identically to those corresponding parts in FIG. 1 are given identical reference numerals and the description thereof will be omitted.
Referring to FIG. 4, a comparator 30 which is a comparator similar to the comparator 16 in FIG. 4 produces a series of pulses having a constant peak-to-peak level on the basis of comparison of the input frequency modulated luminance signal with a predetermined reference voltage V TH . These pulses are outputted from a non-inverting output terminal (+) of the comparator 30 as it is and further outputted from an inverting output terminal (-) as inverted pulses having an inverted waveform to the waveform of the output pulses from non-inverting output terminal. The output pulses from the non-inverting output terminal of the comparator 16 and the output inverted pulses from the inverting output terminal of the comparator 16 are supplied to a non-inverting input terminal and an inverting input terminal of a differential amplifier 33 after passing through low pass filters 31 and 32. The differential amplifier 33 amplifies the difference between the d.c. average levels of the input pulses and the inverted pulses respectively supplied to the non-inverting input terminal and the inverting input terminal of the amplifier 33 and produces a d.c. output voltage having a level twice as large as the level of the d.c. distortion component α. This d.c. output voltage is inverted in phase in an amplifier 34 and a d.c. distortion component α is supplied to the subtractor 21. Thus, the effect of the distortion in the frequency modulated luminance signal is removed and the output pulses having the 50% duty cycle is obtained from the terminal 17. It should be noted that the number of circuits used in the distortion eliminating circuit 15 is reduced as compared to the circuit in the first embodiment.
Further, various variations and modifications may be made without departing from the scope of the present invention. | A distortion eliminating circuit for eliminating a harmonic distortion from an input frequency modulated luminance signal comprises a comparator for producing a series of output pulses responsive to the input frequency modulated luminance signal by comparing the level of the frequency modulated luminance signal with a predetermined level, a filtering circuit for extracting a d.c. component from the series of output pulses by filtering out oscillating components from said output pulses, a detecting circuit for extracting a d.c. distortion component corresponding to the harmonic distortion in the input frequency modulated luminance signal by comparing the level of the d.c. component by a reference level, and a level adjusting circuit for adjusting the level of the input frequency modulated luminance signal by adding or subtracting the d.c. distortion component to the input frequency modulated luminance signal and for supplying the input frequency modulated luminance signal having a level now thus adjusted to the comparator. | 7 |
FIELD OF THE INVENTION
[0001] The present invention is directed generally toward floor and wall covering tiles. More particularly, it is directed towards a tile system that does not require a grout compound to be applied to the tiles after installation.
BACKGROUND OF THE INVENTION
[0002] Ceramic tiles are widely used as a floor and wall covering in both residential and commercial applications. Tile is very versatile, and has been in use as a floor and wall covering for centuries. Tiles are available in a nearly unlimited color palette and may be installed in an equally unlimited number of designs. Tile is often a top choice for floor and wall coverings because of its great durability and aesthetic qualities.
[0003] While many tiles are manufactured from ceramic compositions (baked clay), they may be made of a variety of natural or synthetic materials including, but not limited to, granite, quartz, marble, soapstone, plastic, wood, or any other suitable material.
[0004] Tile provides a durable surface and may be coated to be substantially impervious to water and other liquids. When tiles are installed, they are generally laid side by side on a surface such as a floor or wall. Typically, an adhesive compound is used as a base to attach the tiles to a surface and then grout is spread over and between the tiles to further bind the tiles to the surface and to fill spaces between adjacent tiles. While not impervious to water and moisture, the grout provides a barrier to reduce moisture between and behind the tiles. This step of grouting the tiles is labor intensive and represents a significant portion of the labor involved in a typical tile installation.
[0005] Due to the time and labor involved in tile installation, it is typically quite costly to have tile professionally installed. Accordingly, many homeowners desire to install tile in their own homes. Unfortunately, this is an extremely tedious process, and many homeowners do not wish to spend the time necessary for a satisfactory installation.
[0006] In recent years, manufactures have attempted to produce do-it-yourself tile solutions that are easier to install. One such attempt is described in United States published patent application number US 2004/0031226 entitled “Pre-glued Tongue and Groove Flooring” by Miller et al. Miller et al. describes a laminated “tile” that uses a pre-applied glue for fastening the tiles together. While this system is easier to install than traditional tiles, it still requires a separate grout to be applied and uses a laminate material rather than a solid tile. A laminate material, is not likely to be as durable as more traditional materials such as ceramic or stone tiles. Additionally, because the Miller et al. tile system makes use of a laminated structure that is susceptible to moisture damage, the installer is required to apply a messy grout composition to the tiles as part of the installation process.
[0007] A previous attempt to produce an easy to install tile is described in U.S. Pat. No. 2,693,102 entitled “Interlocking Wall Tile” by Luster et al. Luster et al. describes a synthetic wall tile system that snaps together. Unfortunately, the Luster et al. tile is not practicable with substantially ridged materials, such as ceramic, granite, or marble. The Luster et al. tiles are molded into a uniform structure of a single material and rigid materials could not be formed into an operable tab structure as taught in the patent. Such a limitation severely limits the aesthetic qualities available for the tiles and thereby reduces the marketability of the system.
[0008] Accordingly, there is a need in the art for a tile system that is simple to install.
[0009] Additionally, there is a need in the art for a tile system that does not require a grout or sealing compound to be applied to the tiles after installation.
[0010] Further, there is a need in the art for an easy to install tile system that makes use of durable tile materials.
[0011] Also, there is a need in the art for a tile system that primarily utilizes traditional tile materials, but eliminates the need for grout.
SUMMARY OF THE INVENTION
[0012] The present invention is directed toward a covering for a planar surface comprising a first tile having at least a first and second first tile sidewall carrying a first flange along the respective sidewalls, a second tile having at least a first and second tile sidewall carrying a second flange along the respective sidewalls, the first flange being matingly adapted for attachment to the second flange carried by the second tile.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention will be more readily understood from a reading of the following specifications and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein:
[0014] FIG. 1 is a top view illustration of a tile in accordance with an exemplary embodiment of the present invention;
[0015] FIG. 2 is a plan view illustration of a tile in accordance with an exemplary embodiment of the present invention;
[0016] FIG. 3 is a plan view illustration of two adjacent tiles in accordance with an exemplary embodiment of the present invention;
[0017] FIG. 4 is a plan view illustration of two adjacent tiles in accordance with an exemplary embodiment of the present invention; and
[0018] FIG. 5 is a top view illustration of a tile in accordance with an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Referring now to the drawings, in which like numerals refer to like parts throughout the several views, FIG. 1 is a top view illustration of a tile 100 in accordance with an exemplary embodiment of the present invention.
[0020] The present invention is directed toward a tile system that does not require the use of a separate grout compound during installation of the tiles. Rather, the tile system incorporates tiles having a flange 110 attached to the perimeter of each tile 100 and is attached to an adjacent tile 100 during installation. In accordance with an exemplary embodiment of the present invention, a tile 100 comprises a primary tile component 115 and a flange 110 . Typically, the primary tile component 115 may be a ceramic compound. Alternatively, the tile substrate 115 may be, but is not limited to, plastic, wood, stone, granite, marble, or any other suitable natural or synthetic material. Generically, the primary tile component 115 refers to an outer visible layer of the tile.
[0021] Typically, the primary tile component 115 has a substantially planar outer surface with depending sidewalls. Flange 110 may be a single cut out piece which is positioned around the tile perimeter abutting the tile's sidewalls. Preferably flange 110 in an exemplary embodiment of the present invention is applied to the primary tile component 115 using a rapid injection mold die. Alternatively, any suitable method for adhering the flange 110 to the primary tile component 115 may be employed. For instance flange 110 may comprise distinct components which are separately adhered to the perimeter of the primary tile component. Preferably, the sidewalls have a predetermined height and the flange abuts the sidewalls at a height at least up to the mid-point of the sidewalls. Also, the flange may abut the entire perimeter of the tile.
[0022] In an exemplary embodiment of the present invention, the flange 110 , may be of polymeric material and preferably is a polyurethane material, such as ELASTOCASTr70654 by BASF®. ELASTOCASTr70654 is an unpigmented, 77 to 79 Shore D urethane elastomer designed for cross-sections up to three inches which has some inherent tackiness. This system is based on the ELASTOCAST7073 system.
[0023] The following data may be helpful in producing the material used in a flange 110 in accordance with an exemplary embodiment of the present invention. This data is provided for example only, and is not intended to limited the scope of the invention. Other compositions may be used to fabricate the flange 110 .
Mix Ratio @ 105 index: 100 parts of ELASTOCASTr7065R Resin 771. parts of WUC 3192T ISOCYANATE Specific Gravity: Resin 1/048 f/cc, 8.72 lbs./gal. @ 77° F. Iso 1.22 g/cc, 10.2 lbs./gal. @ 77° F. Viscosity: Resin 1120 cps @ 77° F. Iso 200 cps @ 77° F. Typical Reactivity: Hand mixed at 86° F. at 105 index Gel time: 180 to 240 seconds Recommended Component Resin 75-95° F. processing conditions: temperatures: Iso 75-95° F. Mold temperature: 130-160° F. Demold time: 10-20 minutes
[0024] Alternatively, other polymer variations, such as polyamides, vinyl polymers and polyoletins may be used. Preferably, the flange 110 may be made, but is not so limited, from a material that is chemical resistant, stain resistant, non-porous, and formable to within sufficient precision. Additionally, it may be desirable for the flange 110 to have sealing qualities so as to impede the intrusion of moisture between and behind the tiles and adherence qualities so as to minimize or present movement or displacement of the tiles.
[0025] The flange 110 may take a variety of forms. In an exemplary embodiment of the present invention, the flange 110 may be a dovetail configuration for matably engaging a correlated dovetail pattern on a second tile 100 . In such an arrangement, the two tiles 100 lock together to form a lock-joint. In addition to dovetail joints, any alternative locking joint may be used such as, but not limited to a tongue and groove joint. In another exemplary embodiment of the present invention, the flange 110 may lock two tiles 100 together using adhesive properties in the flange material. In such an arrangement, the flange 110 may be designed to provide sufficient tack so as to lock the tiles together through adhesion. In such an arrangement, it may be desirable to provide a removable backing strip on the exposed tacky surfaces of the flange 110 so that it will not collect dust and other particles prior to installation. Accordingly, the removable strip may be removed at the time of tile installation.
[0026] The tile 100 may also include a base substrate 105 . The base substrate 105 may provide a base upon which the remainder of the tile elements are constructed. The base substrate 105 may also provide additional strength for the tile 100 . Because the base substrate 105 is covered by the primary tile component 115 , the appearance of the base substrate 105 may not be critical. Thus, it may be desirable to use a scrap tile material, or other inexpensive material, for the base substrate 105 to minimize costs. In an exemplary embodiment of the present invention, the primary tile component 115 is attached above the base substrate 105 using an adhesive component 112 . The adhesive component 112 may be the same polyurethane used for the flange 110 . Alternatively, the adhesive component 112 may be any adhesive suitable for binding the primary tile component 115 to the base substrate 105 .
[0027] The primary tile component 115 may be disposed in an offset configuration as shown in FIGS. 1 and 2 . FIG. 2 illustrates a plan view of a tile 100 in accordance with an exemplary embodiment of the present invention. In such a configuration, a portion of the top surface of the base substrate 105 adjacent two of its side edges 106 , 107 is exposed adjacent two side edges 116 , 117 of the primary tile component. Additionally, two side edges 118 , 119 of the primary tile component 115 hang over two of the side edges 108 , 109 of the base substrate 105 . This configuration allows adjacent tiles 100 to overlap partially when installed on a floor or wall in a typical abutting arrangement.
[0028] As shown in FIG. 2 , adhesive 112 may be integral and of the same material as flange 110 . Adhesive 112 may be partially exposed on the upper surface of base substrate 105 enabling attachment of a second tile 100 as shown in FIG. 3 .
[0029] For some installations, it may be desirable to include an underlayment 205 that acts as a moisture or sound barrier. Additionally, the underlayment 205 may serve a surface leveling function. Further, the underlayment 205 may serve as an adhesive for attaching the tiles to an installation surface, such as a floor or a wall.
[0030] FIG. 3 shows an excerpt of a plan view of two adjacent tiles 100 in accordance with an exemplary embodiment of the present invention. As shown in FIG. 3 , two adjacent tiles (tile A and tile B) overlap when installed beside each other. The leading edge of the primary tile component 115 a of tile A extends over the base substrate 105 b of tile B. As shown in this figure, flange 110 b which is attached to primary tile component 115 b is utilized for abutting a sidewall of primary tile component 115 a. This illustrates that while the preferred embodiment utilizes flange 110 around the entire perimeter of primary tile component 115 , some configurations may be had wherein, flange 110 is selectively located on certain predetermined sidewalls of primary tile component 115 such as only three sides or two sides.
[0031] Alternatively, the base substrate 105 and the primary tile component 115 may be manufactured as a single piece. This combined piece may have a profile such that the overlapping configuration shown in FIGS. 1-3 is duplicated without the use of separate base substrates 105 and primary tile components 115 . Further, the primary tile component 115 may be used alone without a base substrate 110 . In such an embodiment, adjacent tiles 100 would not overlap and the flange 110 of a first tile 100 would abut the flange 110 of a second tile 100 .
[0032] FIG. 4 shows an excerpt of a plan view of two adjacent tiles 100 (tile A and tile B) in accordance with an exemplary embodiment of the present invention, wherein the primary tile component 415 is not disposed above a base substrate 105 . As is shown in FIG. 4 , two primary tile components 415 a and 415 b lie adjacent one another and the flange 410 a of tile A abuts the flange 410 b of tile B. In such an arrangement, it may be desirable for the two flanges 410 a and 410 b to attach adhesively. Alternatively, the two flanges 410 may interlock as described above in a dovetail or other locking arrangement.
[0033] FIG. 5 shows a top view of a tile 100 in accordance with an exemplary embodiment of the present invention. As shown in FIG. 5 , the flange 110 may be formed with a plurality of dovetail connections to allow a locking joint with adjacent tiles. In such a configuration, a male dovetail member 505 may be inserted into a female dovetail member 510 during installation. Preferably, the dovetail components 505 , 510 provide a tight fit so that minimal movement is allowed between tiles.
[0034] Although various embodiments of the present invention have been described herein in detail, it will be appreciated by those skilled in the art, that variations may be made thereto without departing from the spirit of the invention or the scope of the appended claims. | The present invention is a tile system that does not require a grout or other material to be spread over the tiles during the installation process. Accordingly, the tile system includes tiles that carry a flange that attaches to adjacent tiles upon installation. The flange serves the function of the grout and eliminates the need for a separate grout compound. A tile in accordance with the present invention includes a primary tile component and a flange for attaching for other tiles. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
[0003] Not applicable
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The present invention relates to printers. More particularly, the present invention relates to ink jet printers.
[0006] 2. General Background of the Invention
[0007] High quality ink jet printing is usually done in one direction (unidirectional) and in multiple passes to hide repetitive defects in dot placement. For each firing of an ink jet nozzle there may be more than one drop, a main drop and one or more accompanying satellite droplets. These satellite droplets are generally smaller than the main drop and are at varying distance and direction from the main drop.
[0008] Prior art has attempted to reduce or eliminate satellite drops with varying degrees of success. This is usually done by controlling the drive signal to the resistive heater element or piezo-electric element. There is also some prior art for edge-feed thermal ink jet to compensate for topography of the nozzle plate near the edge of the silicon substrate. This prior art typically does not mention controlling satellites, but is concerned with the main drop misdirection.
[0009] One of ordinary skill in this art should be able to find details of the invention not specifically disclosed herein in, for example, patents and other references and prior art products mentioned herein.
[0010] The following patents are believed to be related to the first embodiment of the present invention: U.S. patent Document Nos.:
U.S. Pat. Nos. 4,282,533; 5,406,318; 5,867,189; 6,126,282; 6,247,794; 6,264,850; 6,293,644; 6,299,281; 6,336,710; 6,491,833; 6,505,912; 6,527,354.
[0012] The following patent documents are believed to be related to the second embodiment of the present invention: U.S. patent Document Nos.:
U.S. Pat. Nos. 5,896,154; 6,250,739; 6,367,908; 2002/0054187; 2003/0025749; U.S. Pat Nos. 6,491,377; 6,505,905 (same application as 2003/0025749); U.S. Pat. No. 6,527,376
[0014] The following patent documents are believed to be related to the third embodiment of the present invention: U.S. patent Document Nos.:
U.S. Pat. Nos. 5,859,653; 5,870,117; 6,053,598; 6,302,505; 6,302,506; 6,464,330; 6,497,467; 6,523,926; 6,530,635; 6,536,869
[0016] The following patent documents are believed to be related to the fourth embodiment of the present invention: U.S. patent Document Nos.:
U.S. Pat. Nos. 3,976,756; 4,048,639; 4,246,589; 4,380,017; 4,384,296; 5,142,296; 5,638,101; 6,220,693; 6,491,377.
Japanese patent document no. JP358217372A.
[0018] The following patent documents are believed to be related to the fifth embodiment of the present invention: U.S. patent Document Nos.:
U.S. Pat. Nos. 3,928,855; 4,613,875; 5,337,071; 6,220,693; 6,276,783; 6,293,644; 6,338,545; 6,364,447
[0020] The following patent documents are believed to be related to the sixth embodiment of the present invention: U.S. patent Document Nos.:
U.S. Pat. Nos. 3,981,019; 4,220,958; 4,238,804; 4,393,385; 4,555,712; 4,638,337; 4,827,280; 5,396,273; 5,422,664.
[0022] U.S. Pat. Nos. 5 , 049 , 899 and 6 , 474 , 763 are also believed to be of interest.
BRIEF SUMMARY OF THE INVENTION
[0023] The apparatus of the present invention comprises an inkjet printer, a system for printing, and a method of printing using an inkjet printhead having specially shaped and/or directed nozzle bores to control the distribution of main and/or satellite ink drops.
[0024] The method of printing of the present invention includes intentional directional shifting of satellites for uniform density control.
[0025] The apparatus of the present invention includes a printhead for an inkjet printer, the printhead comprising an ink reservoir and nozzles for ejecting ink from the ink reservoir onto print media, the nozzles being formed in the ink jet printer printhead in a predetermined fashion with bores purposefully shaped and/or directed to determine the formation and placement of satellite droplets when ink is ejected from the ink reservoir when the printhead is part of an inkjet printer.
[0026] In some embodiments: (a) each of the nozzles produces a main drop and a satellite droplet when ink is ejected through the nozzles, (b) each nozzle includes a bore, (c) the bore of each nozzle is shaped such that, when ink is ejected through the nozzles, satellite droplets and main drops are balanced—the combined area of satellite droplet and main drop in a first printing direction is as nearly equal as possible to the combined area of the satellite droplet and main drop in a second printing direction opposite to the first printing direction; this can be achieved, for example, by forming the bores as truncated vertical cones, with each bore including two concentric circles, a larger one at the top, a smaller one at the bottom with the two concentric circles connected by a conical section, and the vertical axis through the conical section being substantially normal to the surface of the nozzle plate; (d) the printhead is used in a printer which prints in two directions, and (e) when ink is ejected through the nozzles, satellite droplets and main drops are balanced—the combined area of satellite droplet and main drop in a first printing direction is as nearly equal as possible to the combined area of the satellite droplet and main drop in a second printing direction opposite to the first printing direction; when ink is ejected through the nozzles, satellite droplets ejected through the nozzles can at least partially overlap the main drops in each direction of printing.
[0027] In some embodiments:
(a) each of the nozzles produces a main drop and a satellite droplet when ink is ejected through the nozzles, (b) each nozzle includes a bore, (c) each bore has an axis, (d) a first plurality of the nozzles have the axes of their bores aligned in a first direction, (e) a second plurality of the nozzles have the axes of their bores aligned in a second direction, and (f) when ink is ejected through the nozzles, satellite droplets ejected through the first plurality of the nozzles are offset from the main drops ejected through the first plurality of the nozzles in a different direction from which satellite droplets ejected through the second plurality of the nozzles are offset from the main drops ejected through the second plurality of the nozzles. This produces dots with nearly equal areas in both printing directions, however, in order to produce a straight line, the firing of nozzles directed in one direction must be corrected to nozzles directed in the other direction, since both main drop and satellite drop are directed.
[0034] In some embodiments:
(a) each of the nozzles produces a main drop and a satellite droplet when ink is ejected through the nozzles, (b) each nozzle includes a bore, (c) each bore has an axis, (d) a first plurality of the nozzles have the axes of their bores aligned in a first direction, (e) when ink is ejected through the nozzles, each of the satellite droplets ejected through the first plurality of the nozzles is offset from the main drop ejected through the first plurality of the nozzles in substantially the same direction and at substantially the same distance; each of the satellite droplets ejected can for example fall within the area of a main drop, thus producing no additional satellite droplets on the media; the inkjet print head can for example travel laterally while printing, and the satellite droplets can for example be laterally offset from the main drops, or the satellite droplets can for example be vertically offset from the main drops. When the satellite droplets are vertically offset from the main drops, the satellite droplets can for example be directed vertically enough to be separated from the main drop on the media; printing laterally in either direction can for example produce main drops and satellite droplets with nearly equal combined areas on the media. Since nozzles are all directed in the same direction, no electronic firing compensation is needed to produce a line. This causes improved uniform density in both bi-directional and unidirectional print modes.
[0040] In some embodiments:
(e) a second plurality of the nozzles have their axes of their bores aligned in a second direction, (f) when ink is ejected through the nozzles, satellite droplets ejected through the first plurality of the nozzles are offset from the main drops ejected through the first plurality of the nozzles in a different direction from which satellite droplets ejected through the second plurality of the nozzles are offset from the main drops ejected through the second plurality of the nozzles.
[0043] In some embodiments the inkjet printer includes means for printing in a single lateral direction so that the main drop and satellite droplet at least partially overlap.
[0044] In some embodiments the bores are aligned so that the main drop and satellite droplet ejected from substantially all of the nozzles at least partially overlap when the printer prints.
[0045] In some embodiments:
(a) each of the nozzles produces a main drop and a satellite droplet when ink is ejected through each nozzle at a fire point, (b) each nozzle includes a bore, (c) each bore has an axis, (d) a first plurality of the nozzles have the axes of their bores aligned in a first direction, (e) a second plurality of the nozzles have the axes of their bores aligned in a second direction, (f) when ink is ejected through the nozzles, the main drops ejected through the first plurality of the nozzles are offset in a different direction from the fire point from which main drops ejected through the second plurality of the nozzles are offset from the fire point.
[0052] In some embodiments:
(a) each of the nozzles produces a main drop and a satellite droplet when ink is ejected through the nozzles, (b) each nozzle includes a bore, (c) each bore has an axis, (d) a first plurality of the nozzles have the axes of their bores aligned in a first direction, (e) a second plurality of the nozzles have the axes of their bores aligned in a second direction, (f) a heater is used to eject ink through the nozzles, and each heater ejects ink through a first nozzle from the first plurality of nozzles and a second nozzle from the second plurality of nozzles, (g) the nozzles are aligned and directed such that when ink is ejected through the nozzles, satellite droplets ejected through the first plurality of the nozzles are offset from the main drops ejected through the first plurality of the nozzles in a different direction from which satellite droplets ejected through the second plurality of the nozzles are offset from the main drops ejected through the second plurality of the nozzles, such that:
in a first direction of printing, the main drop from the first nozzle associated with a heater at least partially overlaps the satellite droplet from that nozzle and at least partially overlaps the satellite droplet from the second nozzle associated with that heater, and in a second direction of printing, the main drop from the second nozzle associated with a heater at least partially overlaps the satellite droplet from that nozzle and at least partially overlaps the satellite droplet from the first nozzle associated with that heater.
[0062] The nozzle bores can for example be oriented such that they eject ink opposite the direction of travel of the print head when the print head is moving and printing.
[0063] The present invention includes an inkjet print head comprising the inkjet print head chip, and an ink jet printer comprising the inkjet print head.
[0064] The nozzle bores can for example be formed in polyimide film; the nozzle bores can for example be cut with an eximer laser.
[0065] The present invention includes a method of controlling the formation and placement of satellite droplets ejected from an ink jet printer printhead comprising the steps of:
providing an ink jet printer printhead having an ink reservoir; forming nozzles in the ink jet printer printhead; installing the printhead in an ink jet printer; ejecting ink from the reservoir through the nozzles in the form of main drops and satellite droplets in a manner to achieve uniform density control by controlling the formation and placement of satellite droplets when ink is ejected from the reservoir of the ink jet printer printhead when the printhead is part of an inkjet printer. The method of the present invention can advantageously use the apparatus of the present invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0067] 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:
[0068] FIG. 1A-1C are schematic views of an inkjet nozzle bore which is angled to the left ( FIG. 1C ), causing satellite droplets to be spaced from the main drop when the print head is moving in the right to left direction ( FIG. 1A ), and causing satellite droplets to at least partially overlap the main drop when the print head is moving in the left to right direction ( FIG. 1B );
[0069] FIGS. 2A-2C are schematic views of an inkjet nozzle bore which is angled to the right ( FIG. 2C ), causing satellite droplets to at least partially overlap the main drop when the print head is moving in the right to left direction ( FIG. 2A ), and causing satellite droplets to be spaced from the main drop when the print head is moving in the left to right direction ( FIG. 2B );
[0070] FIGS. 3A-3C are schematic views of an inkjet nozzle which has a balanced bore ( FIG. 3C ), causing satellite droplets to at least partially overlap the main drop when the print head is moving in the right to left direction ( FIG. 3A ), and also causing satellite droplets to at least partially overlap the main drop when the print head is moving in the left to right direction ( FIG. 3B ); the overlapping of drops is not essential to this embodiment of the present invention—it is sufficient that the bore be balanced enough to cause satellite droplets to be spaced from the main drop when the print head is moving in the right to left direction at approximately the same distance as satellite droplets are spaced from the main drop when the print head is moving in the left to right direction;
[0071] FIG. 4 shows calculations to determine offset of the satellite droplet from the main drop in the balanced nozzle bore shown in FIGS. 3A-3C , shows the calculated placement of the main drops and satellite droplets, and shows that actual placement of the main drops and satellite droplets in the left to right direction and in the right to left direction when fired from the balanced nozzle bore shown in FIGS. 3A-3C ;
[0072] FIG. 5 shows actual placement of the main drops and satellite droplets in the left to right direction when fired from the nozzle bore shown in FIGS. 2A-2C and in the right to left direction when fired from the nozzle bore shown in FIGS. 1A-1C ;
[0073] FIG. 6 shows calculations to determine offset of the satellite from the main drop in the nozzle bore shown in FIGS. 1A-1C , and shows the calculated placement of the main and satellite drops in the right to left direction and in the left to right direction when fired from the nozzle bore shown in FIGS. 1A-1C ;
[0074] FIG. 7 shows calculations to determine offset of the satellite from the main drop in the nozzle bore shown in FIGS. 2A-2C , and shows the calculated placement of the main and satellite droplets in the right to left direction and in the left to right direction when fired from the nozzle bore shown in FIGS. 2A-2C ;
[0075] FIG. 8 shows actual placement of the main and satellite droplets when fired from multiple nozzles, where four nozzles are aligned vertically, the top two nozzles have a bore as shown in FIGS. 2A-2C , and the bottom two nozzles have a bore as shown in FIGS. 1A-1C ;
[0076] FIG. 9 shows calculations to determine offset of the satellite from the main drop in the nozzle bore shown in FIGS. 1A-1C , shows the calculated placement of the main and satellite droplets, and shows that actual placement of the main and satellite droplets in the left to right direction and in the right to left direction when fired from the nozzle bore shown in FIGS. 1A-1C ;
[0077] FIG. 10 shows calculations to determine offset of the satellite from the main drop in the nozzle bore shown in FIGS. 2A-2C , shows the calculated placement of the main and satellite droplets, and shows that actual placement of the main and satellite droplets in the left to right direction and in the right to left direction when fired from the nozzle bore shown in FIGS. 2A-2C ;
[0078] FIG. 11 shows a plot of experimental results with a cyan nozzle offset from the heater in the x-direction, showing the means of x error in a left-to-right direction (circles) and right-to-left direction (triangles);
[0079] FIG. 12 shows a plot of experimental results with a cyan nozzle offset from the heater in the x-direction, for a printhead with two nozzle sizes showing the means of x error for large nozzles (circles) and small nozzles (triangles) when ejected from a printhead having large and small nozzles, such as for example the Lexmark Part No. 18L0042 printhead (sometimes also called the Lexmark No. 83 printhead);
[0080] FIG. 13 shows a plot of experimental results with a yellow nozzle offset from the heater in the x-direction, showing the means of x error in a left-to-right direction (circles) and right-to-left direction (triangles);
[0081] FIG. 14 shows a plot of experimental results with a yellow nozzle offset from the heater in the x-direction, for a printhead with two nozzle sizes showing the means of x error for large nozzles (circles) and small nozzles (triangles);
[0082] FIG. 15 shows a plot of experimental results of main drops with a nozzle offset from the heater in the y-direction, showing the means of y error;
[0083] FIG. 16 shows a plot of experimental results of satellite droplets with a nozzle offset from the heater in the x-direction, showing the means of delta y;
[0084] FIG. 17 shows calculations to determine offset of the satellite from the main drop in the nozzle bore similar to that shown in FIGS. 1A-1C , but where the nozzle bore is formed to offset both the main drop and the satellite droplet, and shows the calculated placement of the main and satellite droplets in the right to left direction and in the left to right direction when fired from that nozzle bore;
[0085] FIG. 18 shows calculations to determine offset of the satellite from the main drop and to determine the nozzle bore characteristics similar to that shown in FIGS. 2A-2C , but where the nozzle bore is formed to offset both the main drop and the satellite droplet, and shows the calculated placement of the main and satellite droplets in the right to left direction and in the left to right direction when fired from that nozzle bore;
[0086] FIG. 19 shows calculations to determine offset of the satellite from the main drop fired from a nozzle bore (not shown) which is offset downward in the y-direction, shows the calculated placement of the main and satellite droplets, and shows that actual placement of the main and satellite droplets in the left to right direction and in the right to left direction when fired from that nozzle bore; FIG. 20 shows calculations to determine offset of the satellite from the main drop fired from a nozzle bore (not shown) which is offset upward in the y-direction, shows the calculated placement of the main and satellite droplets, and shows that actual placement of the main and satellite droplets in the left to right direction and in the right to left direction when fired from that nozzle bore;
[0087] FIG. 21 shows calculations to determine offset of the satellites from the main drops fired from two nozzle bores per heater laterally offset from one another, one of the bores being similar to that shown in FIGS. 1A-1C , the other being similar to that shown in FIGS. 2A-2C , such that in each printing direction one main drop both touches its main satellite droplet and overlaps the other main satellite droplet from the other main drop, and it shows the calculated placement of the main and satellite droplets;
[0088] FIG. 22 shows that actual placement of the main and satellite droplets in the right to left direction and in the left to right direction when fired from the nozzle bores of FIG. 21 ;
[0089] FIG. 23 shows calculations to determine offset of the satellites from the main drops fired from two nozzle bores per heater vertically offset from one another, the bores being similar to that shown in FIGS. 3A-3C , and it shows the calculated placement of the main and satellite droplets;
[0090] FIG. 24 shows that actual placement of the main and satellite droplets in the right to left direction and in the left to right direction when fired from the nozzle bores of FIG. 23 ;
[0091] FIG. 25 is a perspective view of an exemplary embodiment of an inkjet print head of the present invention; and
[0092] FIG. 26 is a perspective view of an exemplary embodiment of the inkjet printer of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0000] Balanced Satellite Distributions
[0093] In the first embodiment of the present invention the nozzle openings are formed with a balanced bore (see FIG. 3C ) to cause satellite droplets to be spaced from the main drop when the print head is moving in the right to left direction at approximately the same distance as satellite droplets are spaced from the main drop when the print head is moving in the left to right direction; in FIGS. 3A, 3B , and 3 C, the nozzle bores are formed such that the satellite ink drops touch the main drops in both directions of printing (see FIGS. 3A and 3B ).
[0094] It is the distance and direction of the satellite droplet from the main drop that the first embodiment of the present invention proposes to control. By controlling this distance and direction one can reduce the repetitive differences between printing right-to-left and printing left-to-right. High quality ink jet printing in two directions (bi-directionally) reduces the printing time by half.
[0095] Satellite steering is caused by the bore angle of the nozzle hole with respect to the silicon substrate surface (see FIGS. 1A-3C ).
[0096] A bore angled to the left causes satellite predominance in the R2L direction (see FIGS. 1A-1C , 5 , and 6 ). A bore angle to the right causes L2R satellite predominance (see FIGS. 2A-2C , 5 , and 7 ). Satellite location with respect to the main dot depends on a number of factors that will be detailed below. Maximum allowable angle for a balanced satellite distribution depends on the drop velocity, carrier velocity, and paper gap. Gravity and air turbulence are ignored and have been found to be negligible in practice.
[0097] Once the printhead gap and drop velocities are known along with the associated tolerances for each, one can calculate the angular tolerance needed to maintain a balanced satellite pattern.
[0098] Balanced satellite distributions R2L and L2R create print swaths of uniform color and density (see FIGS. 3A-3C and FIG. 4 ). High quality printing in both directions (bi-directional) can be achieved when satellite distributions are balanced. This achievement allows doubling the print speed of the printer.
[0000] Alternating High Frequency Satellite Direction
[0099] In the second embodiment of the present invention the nozzle openings are formed with all bores in one pair of rows facing to the left, then all bores in the next pair of rows facing to the right, to cause the printing pattern in one direction (e.g, left to right) to be a vertically offset mirror image of the printing pattern in the other direction (i.e, the satellite ink drops are spaced from the main drops in one pair of rows in one direction at approximately the same distance as the satellite ink drops are spaced from the main drops in the next pair of rows in the other direction (see FIG. 8 )); in FIG. 8 , the satellite ink drops touch the main drops in every other pair of rows in both directions of printing.
[0100] It is the distance and direction of the satellite droplet from the main drop that the second embodiment of the present invention proposes to control. By controlling this distance and direction one can reduce the repetitive differences between printing right-to-left and printing left-to-right.
[0101] Here it is the intent to purposefully change the satellite direction at some high frequency in the y-direction (printhead swath width). This means that every pair of nozzles or every (1 . . . n) nozzles, have satellites directed in one print direction only. The next pair of nozzles or set of (1 . . . n) nozzles has satellites directed in the opposite direction.
[0102] By directing multiples of satellites in opposite directions, one can achieve the same effect as balancing satellites R2L and L2R. High quality bi-directional printing can be achieved with a 2× increase in speed.
[0103] Once the printhead gap and drop velocities are known along with the associated tolerances for each, one can calculate the angular tolerance needed to maintain the directed satellite pattern.
[0104] Directed satellite distributions R2L and L2R create print swaths of uniform color and density. High quality printing in both directions (bi-directional) can be achieved when satellite distributions are directed at some high frequency (1 . . . n)/dpi. This achievement allows doubling the print speed of the printer.
[0000] Elimination of Satellites in One Printing Direction
[0105] In the third embodiment of the present invention (see FIGS. 9 and 10 ) the nozzle openings are formed such that all bores face to the left ( FIG. 9 ) or to the right ( FIG. 10 ), so that in one direction there are no satellites (as all the satellites will overlap the main drops). This allows high quality printing if one is willing to print in one direction only (thus doubling the print time).
[0106] It is the distance and direction of the satellite droplet from the main drop that the third embodiment of the present invention proposes to control. By controlling this distance and direction one can produce printing in a single direction that is free of satellites. This allows very uniform controlled printing in one direction.
[0107] Once the printhead gap and drop velocities are known along with the associated tolerances for each, one can calculate the angular tolerance needed to maintain a predominantly L2R or R2L satellite pattern.
[0108] Unidirectional high quality printing can be achieved when satellite distributions are altered using bore angle. This achievement allows excellent control over dot placement and print uniformity.
[0000] Steering Main Drops
[0109] In the fourth embodiment of the present invention the nozzle openings are formed with all bores in one pair of rows facing to the left, then all bores in the next pair of rows facing to the right, to cause the printing pattern in one direction (e.g, left to right) to be a vertically offset mirror image of the printing pattern in the other direction (i.e, the satellite ink drops are spaced from the main drops in one pair of rows in one direction at approximately the same distance as the satellite ink drops are spaced from the main drops in the next pair of rows in the other direction (very similar to the second embodiment, but in this one the main drops are primarily the ones being directed, while in the second embodiment it is the satellite drops which are primarily the ones being directed).
[0110] By controlling the direction of the main drop relative to the desired line of dots one can create a pattern with high frequency or random pattern that will exhibit less defects. This allows very uniform controlled printing in both directions.
[0111] Controlling the main drop position relative to the desired in-line firing of nozzles involves offsetting the inkjet nozzle relative to the heater. Change in the main drop position in the x-direction can be accomplished by offsetting the nozzle in the x-direction (see FIGS. 11 - 14 —the reference point was different between the cyan graph ( FIGS. 11 and 12 ) and the yellow graph ( FIGS. 13 and 14 ), consequently the slope is reversed). A change in the main drop position in the y-direction can be accomplished by offsetting the nozzle in the y-direction (see FIGS. 15 and 16 ).
[0112] In addition to nozzle hole offset, a bore angled to the left causes main drop movement to the left ( FIG. 17 ). A bore angle to the right causes main drop movement to the right ( FIG. 18 ). Main drop location with respect to the fire point depends on a number of factors that will be detailed below. Desired tolerance on bore angle for main drop deflection depends on the drop velocity, carrier velocity, and paper gap. Gravity and air turbulence are ignored and have been found to be negligible in practice.
[0113] Once the printhead gap and drop velocities are known along with the associated tolerances for each, one can calculate the angular tolerance needed to maintain main drop deflection to the right or to the left (see FIGS. 17 and 18 ).
[0114] Here it is the intent to purposefully change the main drop direction at some high frequency in the y-direction (printhead swath width). This means that every pair of nozzles or every (1 . . . n) nozzles are directed say to the right. The next pair of nozzles or set of (1 . . . n) nozzles is directed in the opposite direction.
[0000] Using Satellites to Fill Swath and Improve Uniformity
[0115] In the fifth embodiment of the present invention the nozzle openings are formed with an upwardly or downwardly directed bore to cause the satellite ink drops to be offset in the y direction so one can increase the space between the main drops and still have full coverage.
[0116] By controlling the direction of the satellite droplet relative to the main dot one can use the satellite droplets to fill white space between lines of main drops.
[0117] In this embodiment reduced print density variation can for example be achieved by directing the satellites in the vertical axis far enough to be separated from the main dot on the print media. This placement ensures that as the carrier moves in either direction the satellite will fall outside the main dot. The result is a consistent ink print coverage and equal density in either direction. This technique is also of benefit to unidirectional printing. Variation in satellite trajectory within the nozzle array can cause some of the satellites to fall within the main dot area and others to fall outside the main dot area. This results in density bands within the printed swath. By directing the satellites sufficiently vertically, the satellites fall outside the main dot area in spite of these trajectory variations and the density of the swath is more uniform. In this method, all nozzles can for example have the same vertical satellite directing applied; thus, if the main drop is affected by the satellite positioning technique, all drops are affected equally thereby requiring no electrical timing compensation for re-alignment. The same effect can be achieved by either directing nozzles up or directing nozzles down.
[0118] A nozzle hole bore angled to the left causes main drop movement to the left. A bore angle to the right causes main drop movement to the right. Likewise a bore angled up causes the satellite droplets to land above the main drop (see FIG. 20 ), just as a bore angled down causes the satellite droplets to land below the main drop (see FIG. 19 ). Satellite location with respect to the main drop depends on a number of factors that will be detailed below. Desired tolerance on bore angle for satellite droplet deflection depends on the drop velocity, carrier velocity, and paper gap. Gravity and air turbulence are ignored and have been found to be negligible in practice.
[0119] Once the printhead gap and drop velocities are known along with the associated tolerances for each, one can calculate the angular tolerance needed to maintain satellite droplet deflection up or down to fill in white space between main dots (see FIGS. 19 and 20 ).
[0120] Here it is the intent to purposefully change the satellite droplet location in the y-direction (printhead swath width) and to be able to increase the space between main drop and still have full coverage. Full coverage is achieved by filling in the white space between main drops using satellites deflected above or below the main drop on the printed page. Creating consistent doublets of equal or near equal mass instead of main drop and satellites with differing mass
[0121] In the sixth embodiment of the present invention the nozzle openings are formed with two nozzles per heater and the bore angle is controlled to cause two droplets of approximately equal size and mass (see FIGS. 21-24 ), instead of a main drop and a smaller satellite.
[0122] By controlling the nozzle shape and the direction of the satellite drops relative to the main dot one can create doublets of equal or near equal mass. This allows very uniform controlled printing in both directions. This also allows one to control the effective aspect ratio of the drop, and can be used to increase resolution in one direction. This can be done in either the horizontal (x-direction— FIGS. 21 and 22 ) or the vertical (y-direction— FIGS. 23 and 24 ). It is done by constructing two nozzles per heater and by controlling bore angle of those nozzles.
[0123] A nozzle hole bore angled to the left causes main drop movement to the left. A bore angle to the right causes main drop movement to the right. Likewise a bore angled up causes the satellite droplets to land above the main drop, just as a bore angled down causes the satellite droplets to land below the main drop. Satellite droplet location with respect to the main drop depends on a number of factors that will be detailed below. Desired tolerance on bore angle for satellite droplet deflection depends on the drop velocity, carrier velocity, and paper gap. Gravity and air turbulence are ignored and have been found to be negligible in practice.
[0124] Once the printhead gap and drop velocities are known along with the associated tolerances for each, one can calculate the angular tolerance needed to maintain satellite droplet deflection desired.
[0125] Here it is the intent to purposefully change the satellite droplet location in the x-direction or the y-direction to change the aspect ratio of the drops deposited on the print. By doing this one can accommodate different resolution in x and y directions and still maintain high quality bi-directional printing.
[0126] Inkjet print head 120 ( FIG. 25 ) can include any of the nozzle bore layouts of any of the embodiments disclosed herein. Inkjet printer 130 ( FIG. 26 ) includes inkjet print head 120 . Other than the novel nozzle bore layouts of the present invention, inkjet printer 130 could be the same as, for example, Lexmark® Model Z51, Lexmark® Model Z31, and Lexmark® Model Z11, Lexmark® Photo Jetprinter 5770, or Kodak® PPM200 ink jet printers.
[0000] Processes for Manufacture of Directed Nozzles
[0127] There are several ways to manufacture directed nozzles. An exemplary current process is to use an eximer laser (such as Lambda Physik brand eximer laser, model NovaLine or LPX, commercially available from Lambda Physik) to ablate nozzle hole features in polyimide film. A chrome mask can for example be used to provide the ablation patterns. The nozzle plates can then be die-cut from the film. Other nozzle-plate films could be, for example, polyethersulfone, liquid crystal polymer, polyimide ether, or polyether ether ketone, though polyimide is preferred. These other films can for example be about 10-75 microns thick. A mask other than chrome could be used, such as any material that would block the laser beam and not be degraded by the beam energy). The mask can for example be about 0.5-3.0 millimeters thick.
[0128] In order to produce balanced satellites (as in the first embodiment), laser beam perpendicularity at the object surface should be within about 0.5 degrees, more preferably within about 0.3 degrees, and most preferably within about 0.1 degrees from normal to the nozzle plate film. Hole concentricity can be verified by ablation of a material (such as polyethersulfone, liquid crystal polymer, polyimide ether, polyether ether ketone, or polyimide ) that is thicker (typically about 25-125 microns thick) than the normal nozzle plate material.
[0129] If the nozzles are to be directed all in one direction (as in the third and fifth embodiments), the laser beam can for example be angled (typically about 1-10 degrees from normal, preferably about 1-5 degrees from normal, and more preferably about 1-3 degrees from normal) by adjusting the laser optics and verifying beam angle by ablation of a material (such as polyethersulfone, liquid crystal polymer, polyimide ether, polyether ether ketone, or polyimide) that is thicker (typically about 25-125 microns thick) than the normal nozzle plate material.
[0130] If nozzles are to be directed in multiple directions (as in the second, fourth, and sixth embodiments), the laser beam can for example be adjusted to be normal to the ablated material. An ablation mask can for example be used that has greyscale (uniform small geometric or non geometric shapes that reduce beam transmission, but do not image) to reduce the beam power in a portion of the ablated hole features. Examples of ablation mask material include chrome on glass, where chrome is the patterned material. These masks can for example be drawn with a CAD package, and chrome can for example be the patterned material.
[0131] By using a greyscale mask the wall angle of a portion of the circumference of the ablated holes can be varied to produce the desired non-concentric holes for directing the droplets of ink from the printhead. This is done in the following manner: The greyscale mask is designed to reduce the laser beam energy on one side of each nozzle hole gradually outward radially to the edge of the hole. This produces a nozzle hole with more wall taper on one side than the other. The hole concentricity is shifted in the desired direction. The tangent of the angle produced is the difference between the centroid of the laser entrance hole and the centroid of the laser exit hole divided by the thickness of the ablated material.
[0132] U.S. Pat. Nos. 5378137; 5417897; 5467115; 5948289; 6361145; and 6454393 disclose various methods for making nozzles which could be used to make the nozzles of the present invention.
[0000] Parts List:
[0133] The following is a list of parts and materials suitable for use in the present invention:
120 inkjet print head of the present invention 130 inkjet printer including print head 120
[0136] All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise.
[0137] 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. | A printhead for an inkjet printer includes an ink reservoir and a plurality of nozzles for ejecting ink from the ink reservoir onto print media, the nozzles being formed in the ink jet printer printhead in a predetermined fashion with bores purposefully shaped and directed to determine the formation and placement of main drops and/or satellite droplets when ink is ejected from the ink reservoir when the printhead is part of an inkjet printer. | 1 |
CROSS REFERENCES TO RELATED APPLICATIONS
This patent application is a divisional of U.S. patent application Ser. No. 13/313,658, entitled “System and Method for Collaborative Communications and Information Sharing,” filed Dec. 7, 2011, which is a divisional of U.S. patent application Ser. No. 09/312,740, entitled “Processing Management Information,” filed May 14, 1999, now U.S. Pat. No. 8,095,413, issued Jan. 10, 2012, which claims priority from U.S. Provisional Patent Application 60/133,152, now expired, having the same title as U.S. patent application Ser. No. 09/312,740, and having a filing date of May 7, 1999. This patent application contains the entire Detailed Descriptions of U.S. patent application Ser. Nos. 13/313,658 and 09/312,740.
BACKGROUND
The Web and Internet technology allow far-flung people to be linked and share information as never before, fostering new alliances and revolutionizing business. However, the tools developed so far are primarily intended to enable people to communicate at the individual and team level.
SUMMARY
A computer-implemented system facilitates collaborative communications and information sharing in a network defined by a model. The model of the network is accessible by a user through at least one terminal having a processor. At least a portion of the system, and the model, are stored on a storage component coupled to the terminal. The system includes a context component for capturing context information and user-defined data, the user-defined data provided during user interaction of the user in a first domain of the network, the context component dynamically storing the context information as metadata associated with the user-defined data, the user-defined data and the metadata stored on the storage component of the system; a tracking component for tracking a change of the user from the first domain to a second domain of the network and dynamically updating the stored metadata based on the change, where the user accesses the user-defined data from the second domain; and an interface component for providing an interface to the system accessible by the user at the terminal, the interface permitting the user to create and view the user-defined data according to the model of the network.
DESCRIPTION OF THE DRAWINGS
FIGS. 1 , 2 , and 4 are block diagrams of software systems;
FIGS. 3 , 6 - 10 , and 12 - 40 are illustrations of computer display screens produced by the software systems;
FIG. 5 is an illustration of principles underlying the software systems; and
FIG. 11 is a spider diagram produced by the software systems.
DETAILED DESCRIPTION
The Agile Management Portal program includes Intranet/Internet based software integrated in a process to help organizations such as companies, enterprises, and businesses, to be more agile. The program allows management teams, wherever located, to quickly plan, design, and work on a common portfolio of strategic goals and initiatives the teams believe will make the business grow and prosper, and to gain access to pre-populated external sources of knowledge, expertise and tools via the Internet.
Agility management: In at least some circumstances, Agility means being able to consistently grow and perform better than competitors in the marketplace over time, and Agility management means linking strategic planning, project management, and high performance organizational principles into an integrated set of management tools, templates and services that enable organizations to be more agile.
The Agile Manager can serve as a “management portal” through which people can view both internal organizational goals and external information available to help achieve these goals. The Portal's functional architecture is called The Agile Manager, and has four modules that can be used in a planning and management process: the Agile Manager, the Agile Company, the Agile Baseline, and Agile Know-how,
The Agile Manager Includes:
(1) a business domain structure to which strategic goals and contributing initiatives can be linked. This structure creates a stem-to stern view of how the business works, including customer, value chain, organization and economic domains. This structure allows the user to enter and subsequently explore strategic goals and initiatives germane to either the organization as a whole or to a particular domain. Once the user picks an area of interest, the user is effectively “one click” away from several context sensitive views about investments the organization is making to grow and improve performance.
(2) a gap analysis facility that a management team can use to assess performance gaps and to design how any aspect of the domain structure would have to change to close these gaps.
(3) the ability to create a portfolio of strategic goals and their contributing initiatives using either top down brainstorming or bottom-up association techniques. As a result, teams can effectively start with a clean sheet of paper and reinvent the business from scratch. Or the teams can review an inventory of already on-going activities and relate these activities to each other and to overall strategic goals. Having this portfolio available on-line—subject to permissioning controls—for all to see, keeps members of the organization aware of where they need to go, what it will take to get there, and what actions should be taken to stay on track.
(4) a facility to draw people's attention immediately to changes in the portfolio and its contents that are important to the people in view of their particular roles or interests. This facility gives various common and individualized views of different goals and initiatives that will help diverse groups of people to work together effectively. A history of these changes and related dates is also maintained.
(5) a common attribute structure that provides information (e.g., costs, payback, priority, risks, due dates) for any goal and contributing initiative so the goals and initiatives can be sorted against a piece of information to facilitate ongoing decision making. For example, if resources are limited, the user can sort initiatives by cost, payback, and priority, or if the user wants to see how the portfolio will affect any part of the organization, the user can sort by domain.
(6) the ability to follow a context sensitive link to any goal or initiative and its relevant internal and external sources of knowledge deemed helpful to successful implementation.
(7) a management action plan/agenda utility that managers can use to keep track of pending issues and actions for each strategic goal or initiative. As a result, users can learn about outstanding issues, upcoming agenda items, and the responsible parties. As a result, items are easily found and a user is allowed to see progress related issues before meetings, so that less time is needed to focus management meetings on substantive issues.
The Agile Company:
(8) The Agile Manager also supports the Agile Company program, which includes content that executives can use to assess how well their organization matches high performance criteria and to suggest base-case template programs that can be adapted to accelerate developing agility. Behind the Agile Company is content reflecting 20 traits and characteristics that capture fundamental principles underlying agile, high performing organizations
The Agile Baseline:
(9) The Agile Baseline includes an accessible assessment tool that displays performance criteria that respondents then evaluate in terms of their organization's competency relative to each criterion. The result of this input is displayed as a “spider” diagram that visually helps to convey the extent of any gaps that should be closed to improve competitiveness. The spider diagram helps people focus on opportunities for improvement and makes the rationale for change readily accessible to members of the organization.
Agile Know-How:
(10) Agile Know-how includes a subscription service that provides links to specific knowledge sources and tools that can be helpful to people working on different initiatives. This subscription service fits together with the Agile Manager so the knowledge is accessible in the context in which it is needed.
When the Agile Manager and its modules are used in conjunction with the Agility Management Process, people are better able to work together in a way demonstrated to be correlated with high performance:
Fosters a more adaptive culture (e.g., to relish change and fight inertia): linking goals, projects and their attributes and being able to sort the portfolio to focus on a particular aspect facilitates adapting to changes when they occur. Helps align users behind strategic goals and contributing projects: getting users to “see” in simple outline form where the organization wants to go to grow and prosper, and what it's going to take to get there, which enables users to understand the strategy and to keep their own projects in alignment. Helps employees act and be treated like owners: when people can see a model of the organization and understand how it works they are better able to make decisions about what is important, much as if they owned the organization. Helps make decisions based on benefits and risks to the business: linking proposed initiatives to the model of the organization, and to costs, paybacks, and priorities makes it easier to understand the benefits and risks that could result. Provides well managed structure that encourages teamwork across boundaries: the ability to understand and be informed of changes elsewhere in the organization enhances the ability to work across different disciplines and locations. Encourages people to continuously look for ways to improve the business: enabling management team members to review a table of contents of their business, and to assess gaps between how good they need to be and where they are currently, and to set goals for closing these gaps; this ability of individuals or teams to step back and to “see” the table of contents and to reflect on what changes need to be made to be different in the marketplace and to improve performance is a key ingredient in creating a culture that continually looks for ways to improve the business. Helps people understand better how the pieces of the business work together: the model of the business gives viewers an integrated view of how the business works and how they relate, which provides a valuable context for understanding why something that does not entirely make sense locally could be proper for the business as a whole. Keeps users focused on successfully implementing strategic priorities: The ability to constantly view and be aware of what is in the approved strategic goals and initiatives portfolio keeps members of the organization aligned around common strategic priorities. Makes the management process more cost effective by having information and knowledge available when it is needed: the linking of plans, goals, resources, people and projects into a relational database accessible via the Internet makes valuable information available almost immediately.
The Computing Environment:
To use Agility Manager effectively, an organization may use an intranet with widespread email and Web browser usage. Agility Manager is compatible with modern email systems and with Microsoft and Netscape Web browsers. Typically, no other client-side software is required.
Agility Manager combines sophisticated application code with powerful, industry standard server components. The Agility Manager server includes a database server, a Web application server, and application code written in server-side Java. Agility Manager can use a Microsoft or Oracle database server. For example, Agility Manager may be run on an IBM Websphere application server, or may run on other Java-based application servers. The Agility Manager may run on Windows NT or Solaris or other operating environments.
Agility Manager may be installed on an internal server, or may be hosted on a server such as a Web server and connected via Internet or Virtual Private Net.
Example of an on-Site Installation:
Browsers: MS Internet Explorer 3+, Netscape Navigator/Communicator 3+
Mailers: Email client with click-through URL linking, such as Notes, Outlook, Outlook Express, Eudora, Communicator.
Server OS: Windows NT 4 Solaris 2.5+
Database Server: MS SQL 6.5 Oracle 8 Database administration capability is typically required.
Application Server: IBM WebSphere 1.1 or 2.0
Web Server: MS IIS, Apache, or Netscape
Mail System: SMTP compatible, such as Notes, Exchange, Sendmail, Small, Postoffice.
Example of an Off-Site Installation:
Browsers: MS Internet Explorer 3+, Netscape Navigator/Communicator 3+
Mailers: Email client with click-through URL linking, such as Notes, Outlook, Outlook Express, Eudora, Communicator. Integration and Source Code
The Agile Manager is based on a relational data model.
Screen Map for Agile Manager:
FIG. 1 is a map of the basic structure of the suite of software that shows key functions performed by the Agile Manager and ways in which users can get access to other modules of the suite. The sequence of the map illustrates logical paths users take as different aspects of the goal hierarchy are considered, from deciding what belongs and why, designing and modifying goals and contributing projects, monitoring and pursuing issues related to implementation progress, and getting to specific knowledge found helpful to the context of any particular initiative. A screen by screen description is provided below.
Overview of Corporate Processes Affected by the Agility Management Program
The Agility Management Program helps leaders, managers, and staff conduct normal management practices in everyday corporate life while quickly and effectively using the power of the Internet to gain access to knowledge needed to make decisions. Thus, the program helps leaders and managers to execute daily operations successfully, to continually improve the way they do business to keep abreast of changing competitive conditions and to deliver increasing value to their customers and owners.
The Planning/Execution Cycle (Process)
Technology is transforming virtually every aspect of commerce, and globalization and deregulation are making competition more complex. These forces are causing organizations to go through planning and execution cycles to launch multiple new initiatives to cope. To do this, organizations routinely make assessments of their performance—they consider best practices, they survey customer opinions, they examine market and competitive trends and practices; they create task forces and hire consultants who generate findings and conclusions. To handle these conclusions, organizations conduct planning to establish goals and design initiatives to improve their performance—they hold retreats to develop these visions and they decide on priorities and allocate resources to fund initiatives to bring these visions to fruition. To execute these initiatives, organizations assign staff and hire outside expertise and know-how to get the results they want. To get the results to stick, organizations undertake change management programs to bring people and organizational behaviors into line with what the new initiatives require.
The Agility Management Program software enables people to get organized and communicate much easier and faster as they go through these planning and execution cycles, and to gain access to knowledge and tools that will help them understand how to implement their initiatives more successfully. FIG. 2 illustrates the relationship between the Agile Manager and common planning practices.
Managing a Portfolio of Initiatives
The planning/execution process is repeated again and again across organizations in different departments, functional areas, and lines of business. It is not uncommon for literally hundreds of initiatives to be underway in units across an organization. Some of the initiatives are local initiatives to improve a specific operation and typically do not need to be coordinated with other initiatives. Many initiatives, however, have multiple components that should be coordinated so that they contribute to the accomplishment of a single overarching goal. For instance, a new product requires that processes across the organization from sales and marketing, through operations and manufacturing, and technology to human resources be integrated and aligned so that the product will be introduced in time to exploit an opportunity in the marketplace. Similarly, introduction of new technology, such as a new workstation, often requires coordination of units from information technology, sales and marketing, human resource training, and administration before the new technology can be put into beneficial use.
The Agile Manager not only facilitates the planning/execution cycle for any particular goal or initiative, but also allows the user to put all the priority goals and each priority goal's contributing initiatives into a strategic implementation portfolio or hierarchy ( FIG. 3 .).
The portfolio view relates contributing initiatives or projects to their overarching goals and to each other, and allows the user to sort these initiatives, projects, or goals in a variety of ways. For example, the user can sort the initiatives in terms of their impact on the domain structure of the organization, by strategic factors such as cost, payback, and priority, or according to the status and stage the goals and initiatives are in to allow better management.
Helping Leaders, Managers and Staff Play their Different Roles
People throughout an organization have distinct roles to play in the formulation and implementation of plans. Traditionally, these roles have been substantially formalized, with senior levels likely to do the planning and lower levels likely to do the implementation. Modern email and voice communication have flattened organizational structures by allowing ordinary employees to get access to information on their own without depending on senior levels as the source of knowledge.
The Agile Manager allows effectively everyone to see the goals and projects important to the company and, as shown on FIG. 4 , helps people to play specific roles with a clear picture of the initiatives involved and allows people to contribute ideas.
Overview of how the Software Integrates with a Process in the Agility Management Program
As shown in FIG. 5 , the Agility Management Program reflects principles of effective management of high performing organizations.
The following describes a typical sequence of how a management user/team might use the Agile Manager. The particular example is drawn from an actual implementation of the Agile Manager linking strategic corporate goals and Information Technology initiatives. The Agile Manager structure allows many different business applications, and a key problem it helps solve is bridging a communication gap between business users and their technical counterparts so both sides work off the same page.
Planning:
The first sequence, for planning, starts with users viewing their domain structure ( FIG. 6 ) and deciding where they want to set a new goal (see FIG. 7 ). Users can view the domain structure at different levels of depth from the highest level (shown in FIG. 6 ) to lower levels showing sub-components within each domain (see FIG. 8 ). If they wish, users can display already existing goals (see FIG. 9 ), which helps them to understand what's in the current hierarchy, which can help address issues such as whether particular domains are sufficiently active and whether some existing goals may no longer be appropriate.
Once users have reviewed current activity and debated where the company needs to devote attention to improve future performance, they can select any domain and select an Agile Baseline Mode (“Baseline”). Baseline allows users to critique the selected domain in terms of criteria that The Agile Manager suggests (see FIG. 10 ), or that they provide or modify themselves. Once the users have agreed on the criteria and reached consensus about both how good the criteria need to be and how good the criteria currently are, the results are displayed in a spider diagram (see FIG. 11 ). The spider diagram helps to capture the users' assessment of the current situation and to explain why the domain has been selected for developing new goals to be included in the hierarchy. Subsequently, users can return to Baseline to reassess whether improvement goals and projects that have been undertaken have in fact been successful. This reassessment can suggest new gap areas where new initiatives may be appropriate, or indicate that not enough has been accomplished to sufficiently improve the situation.
After exercising Baseline, users may establish a new goal (by a “new goal” button on the domain screens) (see FIG. 7 for the screen that appears when the button is pushed) to improve performance. Once established, the new goal takes its place in the goal hierarchy and management can decide what should happen next.
For example, even if a goal “expand business with the most profitable customers” has been entered, ideas related to the goal have not been entirely fleshed out, resources have not been allocated, plans have not been formulated, and accountability has not been assigned. The goal is without projects necessary to bring about the desired results. To begin to put these projects together, users can use the gap analysis feature to view each domain and sub-domain in terms of how each domain or sub-domain would have to change if the goal is to be achieved. As users identify these changes, they create in effect a vision of a different company that would achieve the goal (see FIG. 12 ). In this example, two projects or goals to expand business with profitable customers are: to deepen relationships with high net worth clients, and to have profitable products for every segment. Each of these two projects or goals may also in turn be analyzed in the gap analysis process to create other projects or goals that will make them a reality.
As these projects or goals are defined, they are added to the Goals Hierarchy (see FIG. 3 ) that provides access to the strategic hierarchy of goals and contributing projects or goals that the company is working on to improve performance. If the user wants to get more information about the new goal or any goal listed in the hierarchy, the user clicks on the goal of interest to get to summary information as shown in FIG. 13 for the goal “expand business with most profitable customers.”
In summary, the planning sequence allows the user to update company plans either by starting with a clean sheet of paper and brainstorming a new goal and the projects that would bring it about, or by reviewing the existing hierarchy of goals and projects and deciding whether something is missing; Thus, the hierarchy typically includes a combination of new ideas being considered and maturing goals and projects that are in the process of implementation.
Managing the Hierarchy:
The Agile Manager allows managers to keep the hierarchy of goals and contributing goals in constant view and up-to-date with changing circumstances. The hierarchy can be viewed as a totality of goals and contributing goals affecting the enterprise (see FIG. 3 ), or can be viewed by top goals (see FIG. 14 ), depending on the user's interest, or by specific top goal (see FIG. 15 ).
In addition, the user can view the hierarchy against certain types of information that help inform the user about the impact of goals on the business domains (see FIG. 16 ) or the priority (see FIG. 17 ) or impact of each of the goals, or about its status, stage of development, or ownership accountability (see FIG. 18 ). Because these different views are a click away, the Agile Manager supports a dynamic decision making process where discussion can move quickly from strategic to tactical considerations. For example, if the topic is budgets, the user can sort by goal or project cost (see FIG. 17 ), or by priority or return on investment (“payback”) (see FIG. 19 ) and can be provided with information that can help the user decide where to commit resources based on factors such as benefit and risk. In another example, when managers meet and want to focus on key implementation issues, they can opt to switch to viewing “status” factors and can view goals or projects by status (e.g., on track or in need of attention) (see FIG. 18 ), which stage each is in (see FIG. 20 ), risks, or who is responsible. Without the Agile Manager, each view would likely require a special study or report; the Agile Manager makes these different views available at a moment's notice. In addition, managers who want to explore any goal or project in more detail can click on the goal or project of interest and get more information. Similarly, managers who see something missing while reviewing the overall hierarchy can select “new goal” from the menu and enter a new goal or project (see FIG. 21 ).
In at least some embodiments, an especially important view managers can use to manage the hierarchy is a view in which the goals and projects are sorted by domain. This view can be produced for any of a number of levels, e.g., for the entire hierarchy (see FIG. 16 ) or for a selected goal in isolation (see FIG. 24 ). A purpose of this view is to allow managers to understand quickly what initiatives are underway or will affect an aspect of the business. For instance, if a question arises regarding what is being done about market trends, managers can click on any topic on the domain structure (e.g. customer relationships) (see FIG. 23 ) and see immediately what initiatives are underway related to this topic (see FIG. 24 ). Users can also execute searches by name or word in the title of a goal or project (see FIG. 25 ), and can put Alerts in place (see FIG. 26 ) that will flag changes that occur in goals or projects previously indicated as being of particular interest (see FIG. 26 ).
Executing Goals and Projects:
A major purpose of the Agile Manager, in addition to planning and managing the overall portfolio of goals and projects (i.e. the hierarchy), is to help managers accelerate implementation progress related to a goal and its contributing projects. A user has an array of choices to view when reviewing the progress of a selected goal. (The choices available depend on the permission that is granted by the Owner of a Goal to different types of users (see FIG. 27 )).
A “summary” page (see FIG. 13 ) contains information about the goal itself that can be edited (see FIG. 28 ). Other main views for helping to manage include “progress” (see FIG. 29 ) that displays the contributing projects or goals that must be finished or achieved before the parent goal can be fully accomplished. The “progress” view allows managers to view progress for the contributing projects side-by-side to determine whether the projects are properly synchronized or are out of phase with each other.
Other features are useful for managers and teams executing goals and contributing projects. A “discussion” feature (see FIG. 30 ) allows a user on the system to communicate directly about, and in the context of, the goal or project of interest. The owner of a goal can also select a particularly important part of the discussion and put it on an agenda (see FIG. 31 ). Another useful feature includes an ability to link to internal and external sources of information that goal or project teams believe are important to make accessible to users involved (see FIGS. 32 and 33 ). The links provide a practical application of knowledge management because the links allow teams to place information effectively or actually one click away so users can get at the information without excessively disturbing the state of the software. For example, users can hot-link to and open a detailed Microsoft Project plan if the plan is useful to the discussions. Users can place Word documents related to the goal where the documents can be found, and open the documents when needed. Similarly, users can link to Web sites of outside consultants or suppliers that may be related to the goal at hand. In this way, users can start using the software through the domain structure, find out the relevant issues, and access relevant knowledge context sensitively along the way.
The above sections have laid out a description of Agile Manager and the Agile Baseline module In addition, the Agile Manager includes the Agile Company and Agile Know-How modules.
The Agile Company can be added to or made accessible from the Agile Manager and provides a survey that employees can take to assess how well the company or organization is managed in view of high performance criteria. The Agile Company software can be downloaded onto the client's server and a user on the network can complete a questionnaire of multiple pages, such as 20 pages, (exemplified in FIG. 34 ) and then the software can tabulate results to show strengths and weaknesses for sample analysis. The Agile Company also has templates that can be made available to help clients get started with a change program designed to improve specific high performance traits. The goal “expand business with most profitable customers’ shown in FIG. 36 is set up with such a template.
Agile Know-How links users to excerpts of publications about topics relevant to the goals and projects in which they're involved. For instance, the user can stipulate concepts, such as leadership, and specific aspects of the concept, such as senior leadership, and the kind of information needed, such as understanding the concepts, or how to be a good leader, and then get excerpts that match the needed information. In this regard, the Agile Manager enables an organization to use the Agile Manager as a single source for not only information about strategic initiatives but also knowledge available inside and outside the organization that can help make the organization more agile.
The Input Screen and Process Flows Include:
The Goal Hierarchy Screen is the default screen (see FIG. 3 ) and an important navigational screen for accessing details about any single goal or initiative, or accessing various views. Once the goals and contributing projects have been loaded, the default screen presents a goal hierarchy and can be used as follows:
Hierarchy: the left side of the screen presents an outline the top section of which represents the organization's strategic implementation plan, i.e., in which the top level statements represent strategic goals that are the highest level organization goals, and the next indented level statements represent contributing initiatives that are indicated as having to be completed for the strategic goals to be achieved. A user authorized to see the portfolio view can see where the organization wants to go and what it will take to get there, with the goals and projects associated together in one spot. Unassociated Goals: the goals and initiatives under this heading are indicated as being either no longer relevant strategically or not yet placed in the hierarchy. Functions from this screen: If a user is unhappy with the placement of a goal or initiative or wants to adjust attributes of the goal or initiative, the user has only to click on a goal or initiative listed to retrieve its related information. For example, a click on the initiative takes the user to a summary screen (see FIG. 13 for example) for this initiative. The following information fields are available for any goal or initiative: Heading: the entry shows the name of the goal or initiative for which basic information is displayed on this screen. Owner: this entry lists the name of the person responsible for implementation of the goal or initiative and authorized to edit its related information. Parent Goal: this entry lists the name of the goal or initiative immediately above or superior to the initiative that is active. An advantage of showing the parent goal is that a user working on the initiative is instructed that the initiative is contributing to the parent goal. Objective: this entry shows the objective of the initiative so a user is instructed as to what the initiative is specifically to accomplish. History: the entry maintains a running log of changes made to the initiative, and indicated by whom and when. Here is recorded when the project was created and when delegated to the current owner. The changes are monitored by the computer so that the user can identify which changes the user wants to have flagged automatically when they are made (see View Alerts below). Status: this entry identifies the category such as “on-time,” chosen to summarize the status of the goal or initiative's progress, so that the user can determine at a glance whether the goal or initiative is in need of attention. The categories listed here can be modified to fit each client situation when an edit mode is selected. Due Date: this entry indicates the date by which the initiative is to be achieved. Priority: the benefit entry presents a numerical score from 1 (lowest) to 5 (highest) based on user judgment about the relative value of the initiative or goal in terms of improving the business results. For example, the goal may be rated 3 of 5, i.e., average. An advantage of a simple rating is that users can quickly understand the rating scale and then discuss specifically the reasons behind the rating. Risk: this field presents a 1 to 5 numerical score that indicates a risk level for the goal or initiative, such as that the team is new, that the technology is untested, or that the market is new. By keeping track of risk, managers can work proactively to reduce risk and thus increase the probability of a successful implementation. In addition, when there are resource constraints, decisions about which initiatives to continue to pursue may depend on a combination of benefit scores and risk scores to indicate how much managers can count on achieving the initiative and having a positive impact on the business. For example, with a priority score of 3 that is lower than a risk score of 4, a question might be raised about whether to continue to fund the initiative if there are other initiatives that have better benefit/risk characteristics. Project Code: (not shown) this field allows an alphanumeric identifier to be assigned for administrative purposes. Stage: the stage field shows where in the project life cycle the goal or initiative is so that a user can keep track of how the goal or initiative is progressing and what remains to be done. For example, the initiative shown is in the “start up” stage. In the edit mode, several stages are displayed from which the owner can pick one that is descriptive of the status of the initiative. Investment: this field captures the cost of or investment in each particular goal or initiative so the user can readily access financial information related to decision making and priorities. Payback: the payback field refers to the economic return anticipated for achievement of the particular goal or initiative. In conjunction with the investment field, the payback field can allow a ratio of return on investment to be produced, which ratio may play a key decision making role in an assessment of the relative value of one initiative versus another. Rank: (not shown) this field is available for formulas developed for each client for calculating the ranking of each goal and initiative, including the combined values of initiatives contributing to a particular strategic goal. Score: (not shown) the score field relates to a unique calculation of the cumulative value of each goal and initiative based on weighting techniques appropriate to the user (e.g., alignment with corporate values, brand, payback, competitive position, management attitudes). Both the rank and score fields are provided to help users prioritize goals and initiatives in the portfolio. Edit button: when a user clicks on the edit button, the user is taken immediately to the Basic Goal Edit screen (see FIG. 28 ) which allows the authorized owner to modify the basic information about the particular goal or initiative that has been selected. The Project Name and Description fields are for text, the Due Date is for calendar completion date information, and the other fields such as domain, status, benefit and risk priority, and stage present pop-up menus. When changes are submitted, the changes are automatically accessible to whoever uses the system and are captured in the history log. Delegate button: this button allows the user to designate or redesignate the individual who is the owner of the goal or initiative by going to the Delegate Screen (see FIG. 35 ) and searching through names of candidates to whom responsibility can be delegated. Delete button: when this button is selected, the user is automatically asked whether the goal or initiative is to be deleted and, if so, the goal or initiative is deleted and archived in case subsequent retrieval becomes necessary. Project Menu: this pop-up menu lists the choices of views the user can access from the Basic Goal Info Screen as regards the active goal or initiative that has been selected. The view choices include the following: Control Panel: when this choice is made the user is presented with the Control Panel view (see FIG. 27 ) and can review the permissioning rules. If the rules are satisfactory, the user can retreat and proceed along another path. If the rules need to be changed, the user clicks the edit button and is presented with another version of the Control Panel that can be edited and submitted. Only the authorized owner is able to make changes. Project Briefing: if the user wants to understand better how the active goal or initiative relates to the parent goal, the user can click on this choice and will be presented with the Project Briefing screen (see FIG. 36 ). Here salient information is displayed from the Objective field in the basic information related to the selected goal (see FIG. 37 ). In addition, sources of knowledge that may be helpful to access are listed so that the user can hot-link to them if need be. In a typical embodiment, this screen cannot be edited and is just a view. Goal Components: when the user makes this choice, the user is presented with a Goal Components screen (see FIG. 38 ) and, in a typical embodiment, views only the contributing goals that are related to the parent goal. From this screen the user can access different functions including: Select Parent: when the user wants to change the position of an initiative in the hierarchy, the user clicks on this button and is taken to the Select New Parent screen (see FIG. 39 ). On this screen the user can either search for the new parent goal or initiative if the user knows its name, or click on “Select from Project Hierarchy” and be presented with another screen that lists the hierarchy. The user then selects a goal or initiative as the new parent, and when the user clicks on this selection, the original initiative is associated with the new parent and shows up so associated in the hierarchy. Add SubProject: when the user, wants to add a new subordinate initiative with which the user is working, the user can use the “add” button to view New Goal screen (see FIG. 7 ) and enter information about the new initiative using the standard template. When the information is entered, the new initiative is placed appropriately in the hierarchy. Add Milestone: this button allows the user to flag and define major milestones in the initiative, which can be useful for adding more detail if appropriate for monitoring significant targets. The Create Milestone screen allows the user to name and define the milestone and to set a finish date and status. Project History: this button takes the user to a display of project history (see FIG. 40 ) that shows when changes were made, from creation of the initiative to modifications to any of its attributes. This history can be very valuable for tracking key events in the life of a goal or initiative for analytic or other reasons. From this screen the user can also add comments to explain particular events, or add new events. Links: this button takes the user to a view (see FIG. 33 ) of the links to any knowledge sources that the initiative team has chosen to put here so that the knowledge sources will be accessible to any members when necessary. An advantage of this facility is that with the domain structure linked to goals and initiatives and with knowledge linked to the goals and initiatives, the organization is provided with a clear and natural organization for placing and locating critical information when needed. From this screen the user can add links (see FIG. 32 ). Gaps Analysis: this button takes the user to the list of contributing goals/projects (with actual and desired weightings) by domain—screen (see FIG. 12 ). From this list the user can determine whether the changes for each key domain have been identified. If the user is dissatisfied, the user can either select the edit button and change specific information about one or more of the existing contributing goals/projects or click on “Add” to get to the Edit Contributing Goal screen (see FIG. 7 ) In the latter case, the user can select a domain and enter the name of a new initiative, its actual achievement weighting (based on current status) and desired achievement weighting (based on the importance of this initiative to achieving the parent goal). When the new initiative idea is submitted, the software displays the Gap Analysis view with the new initiative added. The user can continue to add new contributing goals/projects by domain. When the user is comfortable that the domains have been covered, the user can click on a listed goal name and proceed directly to its summary screen to begin to flesh out more information about its characteristics such as its owner and objective. In at least some cases, the value of the Gap Analysis is substantial, because it allows users to brainstorm what changes in the domain structure need to be made if a particular goal or initiative is to be implemented successfully. In this regard, the combination of domain structure and gap analysis keeps members of the organization focused on how the organization works and where improvements need to be made for strategic or tactical reasons. View Menu: the menu at the top of the Goal Hierarchy screen (see FIG. 22 ) give the user access to hierarchical views that facilitate decision making related to creating the hierarchy itself, reviewing status, or flagging changes particularly interesting to the user. A description of each of the buttons is set forth in the following sections: Select Domain: When this is selected the domain structure screen is presented (see FIG. 23 ). All Goals View: when this button is clicked, the user is presented with screen (see FIG. 16 ) which repeats the hierarchy on the left and adds relevant information on the right in five categories useful to users when the users want to assess the validity of the current goal hierarchy, including cost, payback priority, domain, and due date (expressed as time remaining before expected completion). From this screen, the user can select other views where the hierarchy is sorted by category represented by the column heading, e.g., is sorted in descending order of costs, screen (see FIG. 17 ), thereby helping people decide whether the level of investment required can be afforded. Likewise, using column headings as buttons, the user can sort the hierarchy into various views according to payback (see FIG. 19 ), priority (see FIG. 19 ), domain (see FIG. 16 ), or due date. These views facilitate meetings and deliberations where users need to quickly produce a variety of sorted views to achieve the variety of perspectives needed to reach informed decisions. For example, a view sorted by payback, with cost information also visible, helps users decide whether the return on investment will be sufficient to justify financially. Sorting by priority allows users to view the relative weightings that have been given to the goals and initiatives based on factors deemed important from a prioritization perspective. In a typical case, from a strategic perspective, the view sort by domain is highly desirable because this view shows how the goals and initiatives affect different aspects of the organization, e.g., from dealing with customers, to processes, organization, and economics. As a result, users can make common sense decisions about, for example, whether all the needed changes in all the domains have been accounted for. Status View: this button takes the user to various views of the portfolio sorted by information fields that indicate how well the goal or initiative is progressing. When the button is clicked, the Projects by Status screen (see FIG. 18 ) is presented, sorted by status categories and showing other column headings that can be clicked on to get Projects by Stage (see FIG. 20 ) or by Owner, Projects by Risk, and Projects by Due Date. Armed with these views, users can decide where to focus their attention to keep projects on track. Alerts View: this button takes the user to the Project Alerts View (see FIG. 26 ) which shows changes a particular user has identified as being of particular interest. From this view, the user can access the Set Alerts and Set AlertsEdit screens and modify the goals and types of changes the computer is to monitor and flag on the user's behalf
In a typical embodiment, the Agile Manager is accessible from every desktop, with appropriate security clearances, for individual or team use on-line, with print out ability for manual use, and for electronic projection to facilitate team meetings. The software is flexible and is arranged to allow the user to make non-structural changes in, for example, the specifics contained. The user changes the “base case” to reflect the desired language and sub-domain elements. As a result, the more the tool is used, the more the tool comes to reflect the user and the user tends to become proficient with the tool.
The technique (i.e., at least a portion of one or more of the procedures described above) may be implemented in hardware or software, or a combination of both. In some cases, it is advantageous if the method is implemented in computer programs executing on programmable computers that each include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device such as a keyboard, and at least one output device. Program code is applied to data entered using the input device to perform the procedure described above and to generate output information. The output information is applied to one or more output devices.
In some cases, it is advantageous if each program is implemented in a high level procedural or object-oriented programming language such as Microsoft C or C++ to communicate with a computer system. The programs can be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language. In some cases, it is advantageous if each such computer program is stored on a storage medium or device (e.g., ROM or magnetic diskette) that is readable by a general or special purpose programmable computer for configuring and operating the computer when the storage medium or device is read by the computer to perform the procedures described in this document. The system may also be considered to be implemented as a computer-readable storage medium that has been configured with a computer program, where the storage medium as configured with the program causes a computer to operate in a specific and predefined manner. | A system facilitates collaborative communications and information sharing in a network defined by a model. The model and a portion of the system are stored on a storage component coupled to a terminal. The system captures context information and user-defined data, the user-defined data provided during user interaction of the user in a first domain of the network, and dynamically stores the context information as metadata associated with the user-defined data, the user-defined data and the metadata stored on the storage component; a tracking component for tracking a change of the user from the first domain to a second domain of the network and dynamically updating the stored metadata based on the change, where the user accesses the user-defined data from the second domain; and an interface to the system that permits the user to create and view the user-defined data according to the model of the network. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention concerns a high current coaxial connection of the type formed by two plug elements that can be connected with one another, in particular for connection of a current-carrying coaxial line to a gradient coil of a magnetic resonance apparatus, as well as a gradient coil with a connected high current coaxial line.
[0003] 2. Description of the Prior Art
[0004] In addition to other apparatuses, magnetic resonance apparatuses (for example) in which the examination subject is exposed to a strong magnetic field for generation of image exposures are known from medical technology. This leads to an alignment of the nuclear spins of the atoms located in the magnetic field, and the measurement signal for the imaging is obtained by the excitation of oscillations by radio-frequency energy. In order to produce a spatial coding of the signals, magnetic gradient fields are used that are generated along the three spatial directions using coils known as gradient coils. The coils for the individual spatial directions are combined into a gradient coil system that, under the circumstances, include a number of individual coils associated with the three spatial directions and is often also designated as a “gradient coil” for short. This gradient coil is spatially fixed in a sealing compound in which it is cast.
[0005] A high current must be supplied to the gradient coil for generation of the gradient fields. The currents employed lie at a few 100 A. For instance, 500-900 A is a typical value.
[0006] Presently it is frequently the case that, since no suitable high current coaxial connections are available for connection of such a gradient coil, the coaxial lines must be split into two individual conductors before the connection to the coil, with the individual conductors in turn being screwed down at the coil. The high current that must be fed to the gradient coil thus no longer flows coaxially. This leads to high alternating forces in the scatter field of the magnet due to the individual conductors, and thus to a high dynamic material load. This presents the danger of a breakage or a loosening of the contact, and burning or carbonizing can arise due to the high energy at the general purpose amplifier (GPA).
[0007] To address this problem, attempts have already been made to make the connection of the gradient coil by means of a high current coaxial connection that includes a plug and a counter-plug that can be detachably connected therewith, the plug exhibiting a contact bolt (housed in an insulation bushing) that can be axially displaced in a direction counter to a reset force. The insulation bushing is housed in a contact bushing that is overlapped by a coupling mounting, while the counter-plug includes a central counter-contact bolt that is held in an insulation bushing that is in turn housed in a counter-contact bushing that interacts with the coupling mounting for connection of the plug with the counter plug. Upon connection of the plug with the counter-plug, the contact bushing as well as the insulation bushing are then moved relative to a contact bolt abutting the counter-contact bolt to establish a reset force, and the contact bushing is moved against the counter-contact bushing. The reset force for such a high current coaxial connection can be generated, for example, by a spring element or a spring element contact.
[0008] However, the contact surfaces via which the electrical contact is established lie transverse or perpendicular to the axis of the plug connection, such that a relatively rigid mounting is required to ensure a permanent electrical connection (in particular with regard to forces that act in the axial direction).
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide a high current coaxial connection as well as a gradient coil with a connected high current coaxial line that are improved with regard to the aforementioned features.
[0010] This object is achieved in accordance with the invention by a high current coaxial connection of the aforementioned type that has two spring contact elements arranged coaxially to one another to establish the electrical contact between the two plug elements.
[0011] The connection is thus fashioned such that the electrical contact for the inner and outer conductors is established by two spring contact elements of the plug elements, which spring contact elements are arranged coaxially to one another.
[0012] In contrast to the conventional practice, the coaxial lines for the gradient coils (which coaxial lines have an inner conductor and an outer conductor) are thus not split into two individual conductors and screwed down at the coil and, moreover, no electrical contacting transverse to the axis direction occurs with contact bolts or bushings. Instead, the electrical contact is established by two coaxial spring elements. In the inventive connection the spring contact elements thus do not serve for generation of an axial reset force but rather are arranged coaxially to one another and establish the electrical contact for the two polarities, namely between the outer and inner conductors of the coaxial line. The spring contact elements can be fashioned exclusively from springs or can include further components that serve directly or indirectly for generation of a spring force, for example in order to connect individual springs with one another.
[0013] Since the currents are coaxially conducted into the sealing compound of the gradient coil, the electromagnetic forces are kept low. One half of the plug (thus one plug element) is, for example, firmly connected with the gradient coil or is cast therewith in the sealing compound, thereby permitting the connection of the other plug element without problems. The counterpart (thus the second plug element) is connected with the gradient coil feed line.
[0014] In the inventive high current coaxial connection, two spring contacts are thus respectively inter-nested and merged in a simple manner into a connection for both polarities for the outer and inner conductor of the coaxial connection or the coaxial line to be connected. The contact principle for the plug is the connection with the aid of spring contact elements that are arranged around the axis of the coaxial connection. The springs or spring elements can even be arranged in part on the one or other plug element or on various plug elements. In particular, an arrangement of the springs or spring elements of the respective spring contact at the gradient coil-side plug element is appropriate. The deforming effect ensues in the radial direction. The springs or spring contact elements are constructed from an electrically-conductive material, thus in particular from a metal or a metal alloy.
[0015] At least one spring contact element can be arranged directly between contact surfaces (in particular between coaxially aligned contact surfaces) of the two plug elements that are to be brought into contact with one another (which contact surfaces proceed into the plug connection) to establish the electrical contact for a respective conductor of the coaxial line of the high current coaxial connection. In this case the electrical contact for the outer or inner conductors that proceed into the plug connection (thus the connection for both polarities) is directly produced by the spring, which thus in the invention serves not only for bringing the contact surfaces together without being directly placed on or between the contact surfaces, but also for enabling the contacting itself.
[0016] For example, the spring contact elements are can be flat springs with a radial effective direction on likewise coaxial contact surfaces that are thus brought into contact with one another by the springs. In this form of the contacting, a certain clearance for the connection exists transverse to the axis direction with the aid of the coaxial spring contact elements. Moreover, a certain axial tolerance compensation is achieved by the contact surfaces being fashioned longer in the axis direction.
[0017] When forces (such as, for example, separation or compression or forces in the axial direction) thus act on the two plug elements, a displacement in the axial direction does not represent a problem for the securing or ensuring of a contact insofar as the contact moves within certain limits that are predetermined by the axial length of the spring contact elements. In contrast to contacting with perpendicular contact surfaces that must lie directly on one another for a secure contacting, a certain longitudinal displacement of the plug elements counter to one another can be tolerated without further measures in the contacting aligned in the axis direction. This tolerance compensation in the axial direction is very advantageous, not least due to the rigidity of the current feed lines employed.
[0018] At least portions of surfaces of bolts and/or bushing elements arranged in the axial direction of the high current coaxial connection can be used to establish the electrical contact of the contact surfaces. Furthermore, contact bolts or contact bushings can be used wherein the actual electrical contact is mediated by the spring contact elements. The bolts or bushings are thus arranged in the axial direction. Preferably, all surfaces provided for establishment of the contact or the elements that carry these surfaces, are aligned axially, with the springs or spring contact elements either being directly applied on the contact surfaces or being brought into contact therewith upon plugging of the two plug elements together.
[0019] Other contact surfaces or contact surfaces of elements fashioned differently can naturally be used. It is only necessary that the contact surfaces are matched to the coaxial alignment of the spring contacts so that a secure contact is ensured.
[0020] According to the invention, the surface closest to the axis can be the contact surface of a bolt element and the further contact surfaces can be surfaces of bushing elements. A bolt element on whose surface (which has the shape of a cylinder shell) the contact face is fashioned for the establishment of the electrical contact with the aid of the spring contact elements is thus provided (for the inner conductor) centrally with regard to the axis of the connection. The connection to a further axially distal contact surface at the other plug element is established by the coaxially inner spring contact element, this axially distal contact surface being a contact surface of a bushing, thus an element that is fashioned as a hollow cylinder. The further axially distal contacting for the outer conductor is achieved by the interlocking (mediated with the aid of the second spring contact element) of two bushing elements of the two plug elements with their respective hollow cylindrical contact surfaces.
[0021] At least one spring contact element can form a cylinder shell. The spring or the contact element with further components is thus fashioned such that, overall, a cylinder shape arises, but naturally certain interstices can remain, for example between individual spring elements. The spring contact element can be formed by a number of individual springs in the formation of the cylinder shell. These can be arranged, for example, at certain intervals (spacings) on a contact surface of a bushing element such that overall the cylindrical design results. It is normally advantageous when the two spring contact elements have an identical design to the effect that both form an identical shape (thus for example a cylinder shell). The difference then merely lies in the radius of the cylinder shell since different radii must be present due to the coaxial arrangement of the spring contact elements around the common axis of the plug connection.
[0022] Furthermore, at least one spring contact element can be fashioned as a lamella (plate or fin). It is thus a spring composed of a number of lamellar individual springs or a spring or a spring element that has transverse connections between the individual lamellae, wherein the lamellae are arranged at a specific distance along a surface (thus a contact surface for the establishment of an electrical contact). A large surface and high stability can be achieved by a suitable connection of the lamellae spacing. In particular given a larger spacing and a suitable elastic strength, it is possible to enable radial tolerance compensation with regard to radially acting forces.
[0023] The lamellae of the spring contact element can be arranged in the direction of the longitudinal axis of the high current coaxial connection. The lamellae are then curved or elastically deformed, for example somewhat to the side. The lamellae thus extend parallel to the axis corresponding to the overall coaxial design of the contacting with the coaxial spring contact elements. The axis-parallel arrangement of the lamellae is the most straightforward and represents a relatively simple design. This arrangement offers the advantage that the elastic forces that act upon loading of the spring elements are comparable in the axis direction. However, an angled arrangement of the lamellae or an arrangement of the lamellae transverse to the axis of the coaxial connection is likewise possible. However, the arrangement in the direction of the longitudinal axis is particularly suitable with regard to the tolerance compensation in the axis direction, since in such an arrangement each lamella is still involved in the contacting even given a small displacement along the axis. The lamellae can be fashioned directly on associated contact bushings and the like, for example welded or soldered. Gluing is also possible, likewise a screwed or riveted mounting, for which the individual lamellae advantageously have extending transverse connections such as webs that offer attachment possibilities.
[0024] As noted above, it is particularly advantageous when the plug elements can be displaced counter to one another within a specific range without interrupting the electrical contact in the axial direction of the high current coaxial connection. Tolerance compensation in the axis direction (thus along the longitudinal axis of the coaxial connection) is thereby achieved. Due to this axial tolerance compensation, the electrical contacting can be ensured even given vibrations that can occur, for example, in the environment of the gradient coils upon operation of the magnetic resonance tomography apparatus. Furthermore, such an axial tolerance compensation is advantageous in view of the high weight (for example, 800 kg) of the coils used in magnetic resonance tomography. Tearing away of the contact and damage to components can be effectively avoided due to the tolerance compensation. The magnitude of the axial tolerance compensation depends on (in addition to the field of use) the dimensions that the springs (which are, for example, fashioned like lamellae) exhibit with regard to the contact region in the longitudinal direction of the coaxial connection. Depending on the application, compensation in the sub-millimeter or millimeter range up to the centimeter range is possible.
[0025] The electrical contact for the conductors of the coaxial line associated with the high current coaxial connection are appropriately separated from one another by at least one insulator element. The electrical contacts that are associated with the outer conductor or the inner conductor extending into the coaxial connection are thus insulated from one another. The insulator material is selected such that the desired dielectric loss factor results. In the general case the insulator element or insulator elements separate not only the electrical contacts but also overall the inner or outer conductor of the coaxial connection in the region of the plug connection or in the region of the coaxial cable. In the inventive high current coaxial connection, the insulator elements for a particular contact can be fashioned in multiple parts and can be present at both plug elements in order to fashion overall a uniform, sealed insulator part upon inter-plugging.
[0026] At least one pin element (in particular made from a glass fiber-reinforced plastic) and/or a collar with a nut for fixing the relative position of the two regions of the plug element arranged coaxial to one another and carrying the contact surfaces, can be provided at least one plug element. Such a pin made from a glass fiber-reinforced plastic or another suitable material can be used in order to secure the different regions of an individual plug element in their position relative to one another. This can likewise or additionally be achieved by arrangements with threaded nuts. The pin element or the pin elements can likewise appropriately directed through insulator elements, such that overall a stabilization of the plug element is achieved.
[0027] Moreover, the invention concerns a gradient coil with connected high current coaxial line as a part of a magnetic resonance apparatus in which the high current coaxial line is connected with a high current coaxial connection as described above. The gradient coil is thus connected by means of the connection to the high current coaxial line supplying the current, the high current coaxial line supplying a current of several of 100 A. This connection is produced by two coaxial spring contact elements as described above. Each spring contact element thereby establishes the connection for one of the two conductors of the coaxial line. A secure contacting that is tolerant with regard to longitudinal displacements in the direction of the coaxial axis is thereby achieved. The occurrence of high alternating forces in the scatter field of the magnet of the magnetic resonance apparatus and the high dynamic material loading associated with this can be avoided. The contact is securely ensured, for example by springs fashioned like lamellae.
[0028] One plug element with the high current coaxial line can be connected according to the invention while the other plug element is arranged at the gradient coil. Only one insertion of the plug element connected with the high current coaxial line is thus required for supply of the current.
[0029] A plug element can advantageously be cast or laminated on the gradient coil. In this case a fixed or non-detachable contact to the gradient coil results. The contact to the gradient coil thus must only be established once before the casting procedure or the lamination occurs. By a positive and non-positive fixing of the one plug element by casting or lamination, it is ensured that no disruptive movements or loosenings of the connection to the gradient coil can occur in the connection region. A current connection that is more secure and largely insusceptible to interruption can thus be realized overall during the operating time of the magnetic resonance apparatus.
[0030] The cast and/or laminated plug element can include at least one wire ring. The contact to the coil and the mechanical connection thereto can be established and ensured with this ring or with the assistance of other connection elements.
[0031] The employed high current coaxial connection is appropriately designed to carry a current of at least 500 A, in particular of at least 600 A. These are the type of currents that are required for gradient coils in magnetic resonance tomography and that the employed high current coaxial connection must accordingly be able to carry. For safety reasons it is preferred when the high current coaxial connection is also designed for higher currents, for example for currents of 700 A or more.
[0032] According to the invention, a connection of high current coaxial lines to gradient coils that is more vibration-insensitive, exhibits lower Lorentz forces and is more secure is achieved by the high current coaxial connection with the two coaxial spring contact elements and by the inventive gradient coil. The connection provides a tolerance compensation in the axis direction (thus in the longitudinal direction of the connection) without splitting the coaxial line into two individual conductors being necessary.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 illustrates the basic contacting principle of the inventive high current coaxial connection in a partially sectional view.
[0034] FIG. 2 shows the plug elements of an embodiment of an inventive high current coaxial connection in longitudinal section.
[0035] FIGS. 3A and 3B show two plug elements of an inventive high current coaxial connection.
[0036] FIG. 4 schematically illustrates an inventive gradient coil with connected high current coaxial line.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The contacting principle of an inventive high current coaxial connection 1 is shown in FIG. 1 . A first plug element (not shown in more detail here and which is the plug element further removed from the gradient coil) has a central contact pin 2 with which the inner conductor of a coaxial line (not shown) connected with the plug element is in electrical contact. A bushing element 3 arranged radially further outwardly is electrically connected with the outer conductor of the coaxial line, for example by a welded or soldered connection.
[0038] The second plug element arranged at the gradient coil has a bushing element 4 situated radially further inwardly as well as a bushing element 5 arranged radially further outward. The surfaces of the contact pin 2 or of the bushing elements 3 - 5 (which are contact bushings) form electrical contact surfaces 6 a and 6 b , and 7 a and 7 b , for the connection of the inner conductor with the outer conductor, thus a complete connection possibility for both polarities. Two spring contact elements 8 and 9 are arranged between the respective contact surfaces 6 a , 6 b and 7 a , 7 b , via which spring contact elements 8 and 9 the electrical contact is established between the two plug elements, namely between the contact surfaces 6 a , 6 b and 7 a , 7 b . The contact surfaces 6 a , 6 b as well as 7 a and 7 b , like the spring contact elements 8 and 9 , exhibit an axial alignment, thus an alignment parallel to the axis of the high current coaxial connection.
[0039] The inner region with the contact pins 2 , the spring contact element 8 as well as the bushing element 4 is separated from the outer region with the bushing elements 3 and 5 and the spring contact element 9 via an insulator element 10 . The spring contact elements 8 and 9 form cylindrical shells from composed of lamellae arranged in the axial direction (thus longitudinally). A certain tolerance range in the axial direction is thereby produced for the electrical contacting, such that a longitudinal displacement of the two plug elements counter to one another can be tolerated without interruption of the electrical contact.
[0040] The plug elements 11 and 12 of an inventive high current coaxial connection 13 are shown in longitudinal section in FIG. 2 . The plug element 11 is located partially in a sealing (potting) compound 14 in which it is cast together with the module to which current should be supplied via the plug element 11 . Wire rings 15 are provided for strengthening the connection.
[0041] Relative to the axis of the coaxial connection the plug element 11 , has a more axis-proximal contact bushing 16 as well as a more axis-distal contact bushing 17 . An insulator element 17 is arranged between the two contact bushings 16 and 17 .
[0042] The contact surfaces 19 and 20 of the contact bushings 16 and 17 , via which the electrical contact to the corresponding contact surfaces of the other plug element 12 is established, are fashioned in the form of the cylinder shells. Spring contact elements 21 and 22 that serve for the direct electrical contacting between the two plug elements 11 and 12 are arranged on these contact surfaces 19 and 20 .
[0043] The individual components of the plug element 11 are fixed in their position relative to one another by the pin element 23 .
[0044] The second plug element 12 , into which the coaxial line with the inner conductor 24 as well as the outer conductor 25 is inserted, has an inner bolt element 26 as well as an outer bushing element 27 , the surfaces of which respectively exhibit contact faces 28 and 29 to establish the electrical contact in the overlapping region of the plugged connection. When the plug elements 11 and 12 are brought together, the respective contact faces 19 and 28 as well as 20 and 29 are brought into contact with one another via the spring contact elements 21 and 22 , such that the electrical contact between the plug elements 11 and 12 of the coaxial connection is established for the two polarities via the spring contact element 21 and 22 associated with the conductors of the coaxial line. Due to the axial orientation of the spring contact elements 21 and 22 , this contact is tolerant with regard to a certain longitudinal displacement; the contact thus remains unrestricted within certain limits even given forces acting in the longitudinal direction via which the two plug elements 11 and 12 are moved counter to one another.
[0045] The second plug element 12 also has a pin element 20 in order to fix the position of the components of the plug element 12 opposite to one another. The pin element 26 as well as the bushing element 27 are separated from one another by an insulator element 31 .
[0046] Without further measures a coaxial connection that is in the position to bear even very high currents (for example the currents to supply a gradient coil) can thus be established with the two plug elements 11 and 12 . A more secure contact is ensured by the two spring contact elements 21 and 22 (thus the two spring elements that are fashioned circumferentially around the axis of the coaxial connection) arranged coaxial to one another.
[0047] FIGS. 3A and 3B show views of the two plug elements 32 and 33 of an inventive high current coaxial connection. The plug element 32 of FIG. 3A has two bushings 34 and 35 between which an insulator element 36 is arranged. Spring contact elements 37 and 38 that surround the longitudinal axis of the plug element and are aligned coaxially to one another, the spring contact elements 37 and 38 respectively extending in the axial direction, are shown on the inner surfaces of the bushings 34 and 35 . These spring contact elements 37 and 38 are respectively composed of individual lamellae that extend in the axial direction.
[0048] The plug element 33 of FIG. 3B forms the counterpart to the plug element 32 of FIG. 3A and correspondingly comprises an inner bolt 39 as well as an outer bushing 40 . If the plug elements 32 and 33 are plugged into one another, the contact between the surface of the bolt 39 and the bushing 34 is established via the spring contact element 37 with its lamellae structure while the contact between the bushing 40 and the bushing 35 is mediated via the spring contact element 38 . The contacts or connections for the different polarities are thus secured by the coaxial spring contact elements 37 and 38 , wherein the lamellae structure of the spring contact elements 37 , 38 particularly advantageously ensures a secure contact given a simultaneous axial tolerance.
[0049] A stop is provided via the cylindrical elements 41 and 42 upon plugging the plug elements 32 and 33 together. The cylindrical element 42 , like the cylindrical element 43 of FIG. 3A , exhibits an outer threading that provides fixing capability. Furthermore, the elements can be fashioned as nuts via which the arrangement of the individual components of the plug element 32 and 33 are fixed relative to one another in cooperation with a collar.
[0050] FIG. 4 shows the basic principle of an inventive gradient coil 44 with a connected high current coaxial line 49 . The gradient coil 44 is shown only schematically, with individual windings 45 being shown. The gradient coil 44 is cast in a sealing compound 46 , wherein it is securely fixed in terms of position. The connection for the two polarities between the gradient coil 44 and the coaxial line 49 is achieved by two plug elements 47 and 48 in which the respective contacting with regard to the outer conductor and the inner conductor fed into the plug element 47 is established by a spring contact element that is arranged between contact surfaces of bushings and pins of the plug elements 47 and 48 .
[0051] The contacting by means of the spring contact elements that are arranged coaxially to one another with regard to the axis of the coaxial connection enables a connection of the gradient coil 44 that is simultaneously vibration-insensitive, exhibits low Lorentz forces, and is secure.
[0052] Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of their contribution to the art. | A high current coaxial connection with two plug elements that can be connected with one another, in particular to connect a current-carrying coaxial line to a gradient coil of a magnetic resonance apparatus, has two spring contact elements arranged coaxially to one another to establish the electrical contact between the two plug elements. | 7 |
This application is a continuation in part of my copending application Ser. No. 11,948, filed on Feb. 13, 1979, now abandoned.
FIELD OF THE INVENTION
The present invention relates to methods and apparatus for commutation in rectifiers and inverters. It is particularly adapted for regulation of electric alternating current machines.
BACKGROUND AND PRIOR ART
A rectifier is a converter which rectifies alternating current from alternating m-phase line current into direct current, with smoothing inductances on the D.C. side or generally with such impedance conditions, that this rectifier operates as a constant current source. An inverter is a converter which transforms direct current from a current source into alternating current, for the loads such as alternating current machines or network represented by a combination of RLC elements. The main difference between a rectifier and an inverter is the fundamental direction of flow of electric power. In a rectifier power flows from the alternating current side to the direct current side. In an inverter it is from the direct current side to the alternating current load. It is possible and in practice quite frequent, that at certain conditions of operation, the flow of power is reversed.
Where rectifiers and inverters are connected to a network, the fundamental method of control of the output is phase control and the fundamental process in the course of operation of an inverter is external commutation. The passage of current from one main branch of a converter to the following--the commutation--is controlled by external voltage. The commutation time, i.e. the time of transfer of current is determined by the angle of phase control, by the magnitude of current and by impedance conditions at the source and load. Semiconductor converters are mostly used as rectifiers with external commutation and the operation of external commutation and the other properties of these converters are commonly known and described in detail in technical papers.
Rectifiers and inverters with internal commutation have the same fundamental properties as similar converters with external commutation. The current commutation, however, does not proceed spontaneously by action of external voltage, but is forced by auxiliary circuits of the converter. The cause thereof is, for instance, a passive load on the alternating side of the inverter, or such a phase position of the alternating voltage at the moment of commutation, that the alternating voltage cannot cause an external commutation. This is rather linked to the direction of flow of idle power. It can be generally said that external commutation is possible where the alternating side is capable of furnishing idle power, for instance with a supply network. Internal commutation is possible in all other cases, for example with passive load, an electric motor or a supply network. Internal commutation can be introduced with all types of loads. It is above all a consequence of how complicated the converter is and how high the respective costs are, that at present rectifiers or inverters with external commutation prevail.
The most significant practical application of rectifiers or inverters with internal commutation are inverters for driving asynchronous motors. It can be supposed that a further important application will be a rectifier or an inverter on a network for power factor compensation, possibly also D.C. drives with improved energy parameters.
Known rectifiers or inverters, without regard to different alternatives of auxiliary commutation circuits, have one common property. It is the characteristic course of the commutation process, which has practically the same properties in entirely different commutation circuits. It is therefore necessary for simplicity to introduce the term "degree of commutation". The degree of commutation is the number of transitions between branches, between main and auxiliary branches, of the converter, which is required for execution of the complete commutation. A complete commutation in rectifiers and inverters involves the complete transfer of current from one main branch to the following main branch. In practice it means the transfer of current from one phase of the alternating side to the following one.
Direct commutation, where electric current passes directly from one main branch to the following, for instance common external commutation, is, from this point of view, a single stage commutation.
Indirect commutation, where electric current in a transfer from one main branch to the following one commutates at first to an auxiliary branch of the converter is at least a two stage commutation. For voltage inverters and also for other types of converters with internal commutation, for instance in pulse converters, the internal commutation proceeds mostly in two stages, and is therefore a two stage commutation.
Thus, the first stage of a two stage commutation is commutation from the main branch to the auxiliary one and generally includes a commutation capacitor, reactors and auxiliary thyristors. The second stage of the two stage commutation is a commutation from the auxiliary branch to the following branch, or main branch, for instance to a return diode of a voltage inverter and to a pulse converter or to a main thyristor of the following phase of a current inverter.
Current inverters with internal commutation are at present used predominantly for speed regulation of asynchronous motors. In known power circuits with thyristors the commutation process proceeds in two stages. The first stage commutation is from the main thyristor to the auxiliary circuit of the commutation capacitor without change in the load current of the phase. In the second stage, commutation is from the auxiliary circuit of the commutation capacitor to the following phase. The transfer of load current between phases proceeds only during the second stage.
To clarify the concept of two stage commutation, the operation of a known two stage commutation system will be discussed with reference to FIGS. 1 and 2. In FIG. 1, a three-phase load L r , L s , and L t is shown. A DC current, I d , is supplied to the system. A first main input terminal of the circuit is connected to the anodes of the main thyristors V1, V3, V5 and auxiliary thyristors V11, V13 and V15. The cathodes of thyristors V1, V3 and V5 are connected to one terminal of loads L r , L s , and L t , respectively, the other terminals of the loads being connected in common. The cathodes of thyristors V1, V3 and V5 are also connected respectively to the anodes of thyristors V4, V6 and V2, whose cathodes are connected in common to the second main terminal. Commutating capacitors C1, C2 and C3 are connected from the cathodes of thyristors V11, V13 and V15 to the cathodes of thyristors V1, V3 and V5, respectively. The cathodes of auxiliary thyristors V11, V13 and V15 are connected to the second main input terminal through thyristors V14, V16 and V12, respectively.
Let it first be supposed that current flows via V1 to phase R of the load, and returns via phase T of the load and V2. At time t0, auxiliary thyristor V11 and thyristor V3 are switched to the conductive state. Capacitor C1 is charged to the polarity indicated in FIG. 1. After thyristor V11 has been switched to the conductive state, the current passes from the path including V1 to the path including V11 and C1. This process has finished at time t 1 . Capacitor C1 is charged up to time t 2 by the load current, cutoff voltage being applied to thyristors V1 from time t 1 to time t 2 (see FIG. 2).
From time t 2 to time t 3 the capacitor charges in the opposite direction, i.e. to a polarity opposite that shown in FIG. 1. At time t 3 , the voltage across capacitor C1 is equal to a value U sr , that is, it is equal to the instantaneous voltage between terminals R and S of the load. At this point, thyristor V3 begins to conduct and commutation takes place from the path including V11, and C1 of phase R to the path including V3, phase S of the load. Thus, the commutation of current in the load takes place within the time interval t 3 to t 4 . During this time, the capacitor C1 is charged to a value such that the voltage across it exceeds voltage U sr by a voltage ΔU given by the following equation: ##EQU1## which--under the condition of L R =L S =L--can be put as ##EQU2##
Thus the final voltage value on the capacitor is
u.sub.C =U.sub.SR +Δu
It will be noted that the above described two-stage commutation has the following disadvantages:
Since the commutation circuits are used both for disconnecting the thyristors and for accumulating power from the inductance of the load, the capacitors must fulfill two rather different functions with partly opposing requirements. Specifically, it is desirable that the time interval t 1 to t 2 in FIG. 2 correspond to the blocking time of thyristors, namely approximately 50 μsec. This leads to a relatively small capacitance value. The low capacitance value would then lead to such high overvoltage on the capacitor and on the thyristors that voltage damage could occur. Thus, while reduction of the capacity of the capacitor optimizes the blocking of the thyristors, for purposes of accumulation of energy, a larger capacitance value would be preferable.
Secondly, the commutation capacitor must be matched to the load, that is changes in the commutation circuit and, in particular, in the commutation capacitor would be required for different motor loads. This, of course, is a great disadvantage.
SUMMARY OF THE INVENTION
It is an object of the present invention to furnish an inverter which does not have the above described drawbacks.
In the three-stage commutation according to the method and system of the present invention, the function of blocking the main valve (thyristor) and the function of securing accumulation of power from the inductances of the load onto auxiliary capacitors are separated. By separating these functions, the following advantages are obtained:
An auxiliary circuit for securing the disconnection of thyristors is proposed which is capable of blocking the current in the thyristor, thereby reducing current to zero at a defined rate and renewing the thyristor's blocking properties without regard to the accumulation of power and the inductance of the load. An auxiliary circuit securing accumulation of power from the inductance of the load is proposed so that power from the load may be accumulated without dangerous overloads.
It is obvious that by separating the two functions it is no longer necessary to be concerned about a direct connection of the motor to the inverter, as the commutation circuits securing the disconnection of the thyristor are designed for the maximum electric current of the load, or nominal load of the converter, and to parameters of the thyristors. The auxiliary accumulation circuits must, however, be adjusted to the respective parameters of different motors. In practice this is reduced particularly to the adjustment of regulation loops. Inverters with three stage commutation are therefore also suitable for driving different motors.
The change from two stage commutation to three stage commutation has some common results for the circuit design of auxiliary commutation branches of the inverter. They can be described as follows: Relative to inverters which operate with two stage commutation, the commutation capacitors C K are reduced so that the interval t 1 to t 2 in FIG. 1 corresponds to the blocking time of thyristors, approximately to 50 microseconds. Thus the condenser is reduced in practice up to 10%. Without further arrangements this would lead to such a high overvoltage on the capacitor and thus also on the thyristors, that voltage damage could occur. By reduction of the capacity it has been made possible to optimize the first function of auxiliary circuits of the inverter, namely the disconnection of thyristors. The second function, accumulation, is best carried out by another auxiliary converter. In practice this is reduced to a rectifier, most frequently to a diode rectifier in a bridge connection, which is suitably connected to the inverter.
A cyclically operable converter system according to the present invention has AC circuits having at least a first and second circuit associated, respectively, with a first and second AC phase. It further has a DC circuit, a load, and controllable main switch means connected in said first and second circuit for controlling the current flow therein. The apparatus of the present invention is an apparatus for carrying out a three stage commutation transferring current from the first to the second circuit. It comprises auxiliary disconnect circuit means operative independently of said controllable main switch means for generating a blocking signal, applying said blocking signal to said controllable switch means of said first circuit, and taking over said current from said first circuit starting at a first predetermined time instant in said cyclical operation. Auxiliary accumulation circuit means is also provided. This is connected to the auxiliary disconnect circuit means for receiving current therefrom starting at a second predetermined time instant following said first predetermined time instant, and for transferring said current to said second phase. The auxiliary accumulation circuit means comprises an accumulating capacitor for storing commutation energy.
The novel features, which are considered as characteristics of the invention, are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof will best be understood from the following description of specific embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a simplified circuit diagram illustrating the prior art two stage commutation;
FIG. 2 is a timing diagram associated with the circuit of FIG. 1;
FIG. 3a is a simplified diagram illustrating three stage commutation;
FIG. 3b is a timing diagram associated with the circuit of FIG. 3a;
FIG. 4 is a schematic diagram of a three stage commutation circuit according to the present invention;
FIGS. 5 and 6 are pulse converters suitable for use in the current source of FIG. 4; and
FIG. 7 is a timing diagram associated with the circuit of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The basic idea of three stage commutation will be illustrated referring to FIGS. 3a and 3b.
Three stage commutation proceeds in the following stages:
I. stage--interval t 0 to t 1 --commutation from the main thyristor T 1 to auxiliary tyristors, inductances and commutation capacitor C K . The inductances L v in FIG. 3a represent the internal inductances of branches and inductances for limiting rapid current fluctuations.
II. stage--interval t 2 to t 3 --commutation from the branch of capacitor C K to the auxiliary branch of the accumulation capacitor C d . The capacitor C d is a D.C. capacitor situated behind the rectifier.
III. stage--interval t 3 to t 4 --commutation from the auxiliary capacitor C d to the main branch of thyristor T 2 , and load current commutation from phase R to phase S.
In some types of inverters with three stage commutation intervals t 2 to t 3 and t 3 to t 4 can overlap, that is thyristor T 2 may be switched on at time t 2 (see FIG. 7). Since time interval t 2 -t 3 is much smaller than time interval t 3 -t 4 (20 microseconds and about 1,000 microseconds, respectively) this timing is insignificant. However, full load current is not switched to phase S and carried by T 2 until time t 4 .
It is obvious that, in comparison with two stage commutation, the transfer of current between phases, i.e. accumulation of load energy in auxiliary capacitors, is accomplished in the third stage when the auxiliary disconnecting circuit is already disconnected. Thus the disconnecting circuit acts independently of any accumulation of load energy. Specific disconnecting circuits are illustrated in FIG. 4 and will be discussed with reference to this figure, although, of course, many variations thereof are possible. As also illustrated in FIG. 4 and discussed in connection therewith, the rectifiers (V31-V36) which are part of the accumulation circuit can also be part of the disconnecting circuit.
The important thing to remember about the accumulation circuit is that, in the third commutation stage, it is connected in series with the above mentioned rectifier on the DC side of the latter. The voltage across the capacitor opposes the direction of current flow in the phase in which the current is decreasing and therefore causes the proper commutation to the new phase. In the limiting case, accumulation capacitor C d becomes infinitesimal and can be considered equivalent to a counter voltage which is introduced into the commuting phase. This counter voltage can be considered an additional commutation voltage which causes the commutation of current between two phases, regardless of whether or not the load is capable of external commutation. During each commutation, a certain amount of energy is accumulated in capacitor C d , the energy being proportional to the magnitude of the current and to the duration of commutation. This energy must then be removed from capacitor C d so that an equilibrium is established. For low energies, it is possible to discharge the capacitor into a resistor or to remove energy by way of a controlled converter to the supply network. The amount of energy accumulated in capacitor C d is a function of the energy accumulated in the inductance of the load. The amount of energy removed from the accumulation capacitor relative to the output of the main converter is an important parameter of the inverter or current rectifier having three stage commutation.
For an asynchronous motor and for a synchronous motor as well as for a load represented by a network, the magnitude of removed energy is for the most part the amount of energy in the inductances connected in series with the internal induced voltages in FIG. 3a. When a network is connected to an inverter with three stage commutation, a very small commutation angle and small accumulated energy results due to small stray inductances. For instance, two to six electrical degrees are typical. The amplitude of the commutation angle can be controlled by the amplitude of voltage on accumulation capacitor C d and thus influence the commutation process.
For asynchronous motors, due to larger stray inductances, the commutation angle amounts to from five to twenty electrical degrees. A larger accumulation of power results, and may constitute from about four to about 15 percent of the nominal output of the motor.
The overall circuit of the present invention is shown in FIG. 4. If an AC network supply is used, the current source 1 in FIG. 4 may consist of six thyristors, V11-V16 connected to form a three-phase fully controlled bridge circuit. Alternatively, DC current can be supplied by means of the pulse converter circuit shown in FIG. 6. The output current of the current source 1 is applied to an inverter block 2 to whose output terminals 2.3, 2.4, 2.5 is connected a load 4. Load 4 is indicated in FIG. 4 as a three phase load, each phase including an inductance (L41, L42, L43) in series with an internal induced emf (U11, U12, U13). Block 2 consists of thyristors V21 and V24 connected in series from an input terminal 2.1 to an input terminal 2.2 and thyristors V22, V25 and V23, V26 similarly connected from terminal 2.1 to terminal 2.2. Output terminals 2.3, 2.4, and 2.5 are connected to the common points of thyristors V23, V26; V22, V25; and V21, V24, respectively.
A rectifier block 3 has input terminals 3.1 and 3.2 and output terminals 3.3, 3.4, and 3.5, the output terminals being connected to output terminals 2.3, 2.4 and 2.5, respectively. Rectifiers V31, V32 and V33 are connected from terminal 3.1 to terminals 3.5, 3.4 and 3.3, respectively, while rectifiers V34, V35 and V36 are connected from terminals 3.5, 3.4 and 3.3, respectively to terminal 3.2. Block 3 has a two-fold function. On the one hand, it serves to withdraw idle power from load 4 to an accumulating capacitor block 5 and, secondly, it supplies a commuting voltage from a commutation block 6 to the thyristors of block 2.
Accumulating capacitor C51 is connected in parallel with block 3, as is a resistor R51. The power transferred from load 4 to accumulating capacitor block 5 can either be dissipated on the discharge resistor R51 or applied to a DC circuit by means of a circuit block 15 having input terminals 15.1 and 15.2 connected to terminals 5.1 and 5.2 of capacitor block 5, and output terminals 15.3 and 15.4 connected to output terminals 1.1 and 1.2 of current source 1. A resistor R151 is connected from terminal 15.1 to terminal 15.4, while a resistor R152 is connected from terminal 15.2 to terminal 15.3. The power stored on capacitor C51 can also be dissipated through application to an AC network by means of a controlled rectifier circuit in a block 14. Also shown in FIG. 4 is a commutating circuit 6 comprising four auxiliary commutating thyristors V61-V64, two overswing rectifiers V65 and V66, two overswing impedances Z62, Z63 and a commutating impedance Z61.
Since the commutating system of the present invention differs considerably from that of the known art, it will be described first, and in detail. The commutating impedance Z61 consists of suitably arranged series, parallel, or series-parallel combinations of capacitors, chokes, resistors, supersaturated coils, or other elements of achieving the desired commutation current pulse. The simplest embodiment is a series LC circuit. For high power applications, more complicated commutating impedances are used, so that the active commutating elements can be used to better advantage. The most advantageous overswing shape is a trapezoidal form, the leading edges of the trapezoid being determined by the allowable steepness of current increase di/dt for the particular valves used, while the amplitude is determined by the maximum load current. The time at which the trapezoidal current pulse occurs determines the switch off instant of the thyristor in block 2. In the beginning phase, the capacitor or group of capacitors in the commutating impedance Z61 is charged to the appropriate polarity, e.g. the positive pole being on the anode of V63. For these initial conditions, a half-sinusoidal or trapezoidal overswing takes place after thyristors V61 and V63 are switched to the conductive state. The voltage across the overswing impedance Z62, connected in series with the overswing rectifier V65, will become more positive at terminal 6.3 and more negative at terminal 6.1. The positive voltage is applied to terminals 2.3, 2.4 and 2.5 through rectifiers V31, V32 and V33, respectively, while the negative voltage is applied to terminal 2.1, i.e. to the anodes of thyristors V21-V23. Thyristors V21-V23 are thus blocked.
The overswing impedances Z62, Z63 can consist of resistors, choke coils, a supersaturated coil, a secondary winding of a transformer which creates a counter emf, or a suitable combination of the aforementioned elements. Depending upon what types of elements constitute the overswing impedance, the cutoff voltage is applied to the main thyristors V21-V23 within a period of from not entirely one-half up to the complete overswing interval. During this time, the polarity of voltage across the overswing capacitor is reversed so that the capacitor (or group of capacitors) has the opposite polarity and is ready to extinguish the lower group of thyristors V24-V26 at the start of the next phase. However, the voltage across the capacitor cannot re-attain its original amplitude, due to losses in the overswing circuit and in the commutating impedance Z61 itself. This is why the capacitors in the commutating impedance Z61 have to be charged. The charging can be achieved by delaying the switching on of the next subsequent main thyristor, so that the current flows into the load via the auxiliary valves, the commutating impedance Z61, and valves 31-36 of block 3. This, however, causes the initial condition on the capacitor and therefore the amplitude of the overswing current to depend considerably on the load current. Therefore, it is preferable to charge the capacitors in the commutating impedance Z61 from an auxiliary source by means of charging valves. Thus, for instance, it is possible to connect a source 9 and charging thyristors V101 and V102 to a charging impedance Z101, whereupon the supply terminals 2.1 and 2.2 of inverter block 2 are to be separated from source 9 by buffer circuits 7, 8. Alternatively, the commutating capacitor may be charged from capacitor C51 through a charging circuit 11, or charging sources can be connected in series with the overswing impedance (12, 13). The charging of commutation impedance Z61 will be discussed in greater detail below.
In the last paragraph, the operation of commutation block 6 has been described in detail. However, in order that the function of the inverter with three stage commutation be correctly understood it is felt advisable to additionally clarify the interaction of the individual blocks during the current commutation between the two main valves of valves V21 through V26 of the inverter block 2.
Let it be assumed that the current from the source 1 flows from the terminal 1.1 via terminal 2.1, valve V21 to the terminal 4.1 of load 4, and returns via L41, U41, U43 and L43 through the valve V26 back to the current source 1. The capacitors in the commutating impedance Z61 are ready to extinguish the upper half of the inverter 2, as e.g. by the positive polarity on the anode of valve V63. At the instant t0 (see FIG. 7) the switching-on of the auxiliary commutating valves takes place and the trapezoidal overswing begins; this means that, in the first phase, the current in the commutating circuit 6 begins to increase with a particular di/dt. Since the current from source 1 is constant, the current flowing through the valve V21 of inverter 2 must proportionally decrease as the commutating circuit current increases. However, as regards the load 4--as apparent from FIG. 7--the current keeps flowing to the terminal 4.1 but, on the one hand, via valve V21 and, on the other hand, through the path 7, V61, Z61, V63 and V31. At the instant t1 the complete current follows the new path and valve V21 is blocked. The overswing amplitude is always greater than the local current so that an excess current is drawn through overswing valve V65 and the overswing impedance Z62. The voltage drop across this reactance is applied via buffer circuit 7 and V31 in the cut-off direction to V21. If using a plain ohmic impedance Z62 (or a recuperating transformer operating to countervoltage) the blocking interval of the valve V21 is given by the period t2 minus t1. At the instant t2 the overswing dies out; its current just attains the load current magnitude. If the voltage on the capacitors in the commutating impedance Z61, which already has the opposite polarity at the instant t0, is higher, as to amplitude, than the voltage on the accumulating capacitor C51, the commutation of the load current changes its path from 7, V61, Z61, V63 to the path V22, V35, C51, V31, provided that the valve V22 already has, or is being given, an ignition pulse. Such commutation takes place up to the instant t3 at which the auxiliary valves are blocked and the entire current flows into the load 4 via V22, V35, C51 and V31. However, at the instant t2, there commences also the commutation of current in the individual phases of the load 4 which means that the current of phase 4.2 begins to increase and the current of phase 4.1 begins to decrease. The commutation power contained in L41 is transferred to the accumulating capacitor C51. The entire process is ended at the instant t4 at which the current of phase 4.1 completely dies out. Simultaneously, or within an interval before the next commutation, the commutating capacitor is charged in any of the afore-mentioned ways.
The above described commutation process constitutes a typical example of the situation occurring when the commutating capacitor is charged from auxiliary sources. When the commutation capacitor is charged by the load current it is possible to postpone the switch-on instant of the valve 22 so that then, within the interval between the instant t2 and the application of the ignition pulse to valve V22, the capacitor in the impedance Z61 is charged by the load current.
For charging the capacitors in the commutating impedance Z61 it is possible to choose one of several variants of the charging source. It is possible to connect the charging source 9 to the terminals 6.1 and 6.2, and to interconnect, between said terminals and the terminal 6.5, a charging circuit 10 comprising a charging impedance Z101 and charging valves thyristors V101 and V102. Ignition pulses for V101 or V102 are then applied simultaneously with those for V62, V64 or V61, V63, provided the impedance Z101 has a sufficiently high inductance or is an appropriately chosen supersaturated coil. Alternatively, it is also possible to retard pulses for V101, V102 and to prolong or double correspondingly the pulses for V61 and V62.
Another charging method consists in a parallel-connection of voltage sources 12, 13 to the overswing circuits V65, Z62 or V66, Z63. In this case either simultaneously with the overswing or with a delay, a part of the current flows via the charging circuit whereby it causes the transfer of power from the charging source to the capacitors in the commutating impedance Z61 or the charging takes place from the accumulating capacitor C51 via valves V111, V112 and charging impedance Z111, similarly as with charging from the auxiliary source 9.
While the invention has been illustrated in preferred embodiments, it is not to be limited to the circuits and structures shown, since many variations thereof will be evident to one skilled in the art and are intended to be encompassed in the present invention as set forth in the following claims. | A three phase current inverter has a commutation circuit wherein a blocking voltage is generated which is applied from the anode to the cathode of the main control thyristors. The load current from the then-conductive phase is simultaneously transferred to the commutating or disconnect circuit. A separate accumulation circuit including a capacitor then takes over the load current, the energy stored in the load inductance being transferred to the capacitance in the accumulation circuit. The control thyristor for the next phase is switched to the conductive state, current is transferred from the accumulation circuit to the subsequent output phase and from the load of the first phase to the load of the second phase. The capacitor in the disconnect circuit is smaller than that in the accumulation circuit so that optimum characteristics for both circuits are obtained. | 7 |
PRIORITY CLAIM
[0001] The present application claims the benefit of copending U.S. Provisional Patent Application Ser. No. 61/127,943, filed May 15, 2008, which application is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to rotary couplers. The present invention more specifically relates to a capacitively coupled rotary coupler for use in a minimally invasive imaging catheter and system.
[0003] Intravascular catheters such as intravascular ultrasonic (IVUS) catheters enable imaging of internal structures in the body. In particular, coronary IVUS catheters are used in small arteries of the heart to visualize coronary artery disease. An IVUS catheter will, in general, employ at least one high frequency (20 MHz-45 MHz) ultrasonic transducer that creates pressure waves for visualization. At least one transducer is typically housed within a surrounding sheath or catheter member and mechanically rotated for 360° visualization.
[0004] The highest frequencies at which commercially available coronary imaging catheters operate are 40 MHz and 45 MHz. These high frequency probes have an axial resolution of approximately 200 microns. An axial resolution of 200 microns is insufficient to resolve structures with size features smaller than 200 microns. For example, thin-cap fibroatheromas having a thin fibrous cap of 65 microns or less in thickness cannot currently be resolved. The concern regarding thin-cap fibroatheromas is that they are prone to rupture. Plaque rupture can lead to thrombus formation and critical blockages in the coronary artery. The ability to reliably identify thin-cap fibroatheromas can aid interventional cardiologists to develop and evaluate clinical treatment strategies in order to reduce post percutaneous coronary intervention morbidity rates. Therefore, IVUS catheters and systems having improved axial resolution capable of more clearly visualizing micron sized features such as vulnerable plaques are needed in the art. The ability for such systems to operate at high transducer frequencies will be important in that effort.
[0005] One of the challenges of these minimally invasive imaging systems is coupling the stationary ultrasound transceiver (transmitter/receiver) to the mechanically rotating transducer. Rotary inductive couplers are used in commercially available IVUS systems. However, rotary inductive couplers are non-ideal for very high frequency (30 MHz-300 MHz) operation because of their relatively high series inductance. At such high frequencies, series inductance will result in an insertion loss into a transmission line of the IVUS catheter. Furthermore, the insertion loss increases with increasing ultrasound imaging frequency which degrades system performance. Rotating inductive couplers also exhibit electrical impedance that can vary with rotational position. The variation of impedance with rotational position causes output signal amplitudes to vary with angular positions and further degrades system performance. The present invention addresses these and other issues towards providing imaging catheters having improved resolution and more constant level output.
SUMMARY
[0006] In one embodiment, an imaging system comprises a catheter having a lumen, a rotatable imaging probe within the catheter lumen including a distal transducer and first and second conductors coupled to the transducer. The system further includes a coupler that couples the rotatable first and second conductors to non-rotatable third and fourth conductors. The coupler includes a rotary capacitive coupler.
[0007] The coupler may comprise a parallel plate capacitor. The coupler may comprise a first parallel plate capacitor that couples the first conductor to the third conductor and a second parallel plate capacitor that couples the second conductor to the fourth conductor or a parallel plate capacitor that couples the first conductor to the third conductor and a cylindrical surface concentric capacitor that couples the second conductor to the fourth conductor.
[0008] The coupler may comprise a cylindrical surface concentric capacitor. The coupler may comprise a first cylindrical surface concentric capacitor that couples the first conductor to the third conductor and a second cylindrical surface concentric capacitor that couples the second conductor to the fourth conductor.
[0009] The coupler may comprise a conical surface concentric capacitor. The coupler comprises a conical surface concentric capacitor that couples the first conductor to the third conductor and a parallel plate capacitor that couples the second conductor to the fourth conductor, a conical surface concentric capacitor that couples the first conductor to the third conductor and a cylindrical surface concentric capacitor that couples the second conductor to the fourth conductor, or a first conical surface concentric capacitor that couples the first conductor to the third conductor and a second conical surface concentric capacitor that couples the second conductor to the fourth conductor.
[0010] The coupler may be within the catheter or outside of the catheter.
[0011] In another embodiment, an imaging system comprises a catheter having a lumen and a distal rotatable imaging probe within the catheter lumen including a first transducer, first and second conductors coupled to the first transducer, a second transducer, and third and fourth conductors coupled to the second transducer. The system further includes a rotary capacitive coupler that couples the rotatable first and second conductors to non-rotatable fifth and sixth conductors, respectively, and a rotary inductive coupler that couples the rotatable third and fourth conductors to non-rotatable seventh and eighth conductors, respectively.
[0012] The coupler may comprise a parallel plate capacitor. The coupler may comprise a first parallel plate capacitor that couples the first conductor to the third conductor and a second parallel plate capacitor that couples the second conductor to the fourth conductor or a parallel plate capacitor that couples the first conductor to the third conductor and a cylindrical surface concentric capacitor that couples the second conductor to the fourth conductor.
[0013] The coupler may comprise a cylindrical surface concentric capacitor. The coupler may comprise a first cylindrical surface concentric capacitor that couples the first conductor to the third conductor and a second cylindrical surface concentric capacitor that couples the second conductor to the fourth conductor.
[0014] The coupler may comprise a conical surface concentric capacitor. The coupler comprises a conical surface concentric capacitor that couples the first conductor to the third conductor and a parallel plate capacitor that couples the second conductor to the fourth conductor, a conical surface concentric capacitor that couples the first conductor to the third conductor and a cylindrical surface concentric capacitor that couples the second conductor to the fourth conductor, or a first conical surface concentric capacitor that couples the first conductor to the third conductor and a second conical surface concentric capacitor that couples the second conductor to the fourth conductor.
[0015] In a further embodiment, an imaging system comprises a catheter having a lumen, a rotatable imaging probe within the catheter lumen including a distal transducer, and a coupler including a rotary capacitive coupler that couples the rotatable transducer to non-rotatable first and second conductors and a rotary inductive coupler that couples the rotatable transducer to third and fourth non-rotatable conductors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further features and advantages thereof, may best be understood by making reference to the following descriptions taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify identical elements, and wherein:
[0017] FIG. 1 is a high-level diagram of a catheter-based imaging system comprising a rotary coupler as part of a catheter interface module;
[0018] FIG. 2 is a schematic representation of electrical signal paths of a catheter-based imaging system comprising a rotary coupler as part of a catheter interface module;
[0019] FIG. 3 is a high-level diagram of a catheter-based imaging system comprising a rotary coupler as part of a catheter;
[0020] FIG. 4 is a schematic representation of electrical signal paths of a catheter-based imaging system comprising a rotary coupler as part of a catheter;
[0021] FIG. 5 is a side perspective view of a parallel plate capacitor;
[0022] FIG. 6 is a side perspective view of a cylindrical surface concentric capacitor;
[0023] FIG. 7 is a side perspective view of a conical surface concentric capacitor;
[0024] FIG. 8 is a diagram of a rotary capacitive coupler located in a catheter interface module and comprised of a cylindrical surface concentric capacitor and a parallel plate capacitor;
[0025] FIG. 9 is a diagram of a rotary capacitive coupler located in a catheter and comprised of a cylindrical surface concentric capacitor and a parallel plate capacitor;
[0026] FIG. 10 is a diagram of a rotary capacitive coupler comprised of a conical surface concentric capacitor and a parallel plate capacitor;
[0027] FIG. 11 is a diagram of a rotary capacitive coupler comprised of cylindrical surface concentric capacitors;
[0028] FIG. 12 is a diagram of a rotary capacitive coupler comprised of conical surface concentric capacitors;
[0029] FIG. 13 is a diagram of a rotary capacitive coupler comprised of parallel plate capacitors; and
[0030] FIG. 14 is a schematic representation of electrical signal paths for a two channel system comprised of a rotary inductive coupler and a rotary capacitive coupler.
DETAILED DESCRIPTION OF THE INVENTION
[0031] A high-level diagram of the components of a catheter-based imaging system is shown in FIG. 1 . A catheter 1000 A is coupled mechanically and electrically to a catheter interface module 2000 A comprised of a rotary coupler 100 . An imaging engine 3000 is in electrical communication with the catheter interface module. Following the imaging engine 3000 is a display engine 4000 and a display 5000 .
[0032] FIG. 2 shows an electrical schematic representation of the transmit and receive signal paths of a catheter interface module 2000 A and catheter 1000 A having a primary purpose of coupling a signal from a stationary electrical conduit to a rotating electrical conduit. Diagrams for a rotary capacitive coupler 100 and ultrasonic transducer 220 are shown. In accordance with this embodiment, the rotary capacitive coupler 100 is located outside of the catheter 1000 A and within the catheter interface module 2000 A.
[0033] FIG. 3 shows a high-level diagram of the components of another catheter-based imaging system. The components 1000 B, 2000 B, 3000 , 4000 , 5000 of the catheter-based based imaging system in FIG. 3 are substantially the same as the components 1000 A, 2000 A, 3000 , 4000 , 5000 of the catheter-based imaging system in FIG. 1 and hence, reference characters for like elements are repeated in FIG. 3 . However, in this embodiment, a rotary coupler 100 is located in the catheter 1000 B.
[0034] FIG. 4 is an electrical schematic representation of the system signal paths of the system of FIG. 3 and to the extent that it is the same as the electrical schematic representation in FIG. 2 , reference characters for like elements are repeated. However, as may be noted in FIG. 4 , the rotary capacitive coupler 100 is located in the catheter 1000 B.
[0035] FIGS. 5-7 show illustrations of parallel plate and concentric capacitors which may be employed in the various embodiments described hereinafter. FIG. 5 shows a side perspective view of a parallel plate capacitor. The capacitance of the parallel plate capacitor depends on the cross-sectional area A plate and separation distance d plate of two parallel plates Plate 1 ,Plate 2 and is closely approximated by
[0000]
C
=
ɛ
0
ɛ
r
A
plate
d
plate
[0000] where C is the capacitance in Farads (F), A plate is the area of each plate in square meters (m 2 ), ε r is the relative static permittivity or dielectric constant, ε 0 is the permittivity of free space (i.e., 8.854×10 −12 F/m), and d plate is the separation distance between the plates in meters (m).
[0036] FIG. 6 shows a side perspective view of a concentric capacitor compiised of cylindrical surfaces. The capacitance per unit length of the cylindrical surface concentric capacitor depends on the radii r 1 , r 2 of the drums (or cylinders) Drum 1 , Drum 2 and is approximately
[0000]
2
π
?
?
ln
(
r
1
r
2
)
.
?
indicates text missing or illegible when filed
[0000] The reactive impedance experienced by a signal of frequency f across the capacitor is |Xc|=(2πfC −1 .
[0037] FIG. 7 shows a side perspective view of a concentric capacitor comprised of conical surfaces. The capacitance of the conical surface concentric capacitor is similar to the capacitance of the cylindrical surface concentric capacitor. The cone separation distance d cone can be varied by adjusting the relative axial position of the cones Cone 1 , Cone 2 . The ability to adjust the separation distance enables variation of the capacitance.
[0038] For a given capacitance C of the capacitors of FIGS. 5-7 , the reactive impedance |Xc| decreases as frequency f increases. Insertion loss for a rotary capacitive coupler decreases with increasing frequency and increasing capacitance. Capacitance can be increased by increasing the relative static permittivity of the capacitor gap filler material, increasing the surface area of the capacitor surfaces, or decreasing the gap between capacitor surfaces. The gap filler material can be a variety of materials including air, polyethylene, quartz, or glass. The benefit of decreased insertion loss to imaging performance is improved axial resolution of the imaging system due to use of higher transducer frequencies.
[0039] FIGS. 8 and 9 illustrate separate embodiments of an IVUS system and catheter wherein a rotary capacitive coupler can either be located in a catheter interface module ( FIG. 8 ) or a catheter ( FIG. 9 ). FIG. 8 shows a diagram of a catheter interface module 2000 A and catheter 1000 A wherein a rotary capacitive coupler 100 A is located in the catheter interface module. The rotary capacitive coupler comprises a cylindrical surface concentric capacitor 110 including concentric drums 110 A, 112 A and a parallel plate capacitor 120 including plates 120 A, 122 A, respectively. The advantage of this design is that the fixed non-rotatable drum 120 A acts as a shield to electrical noise for the parallel plate capacitor.
[0040] A high frequency (>40 MHz) signal travels from a send path 2 to the center conductor 212 of a catheter transmission line 210 in the catheter imaging core, through an ultrasound transducer 220 , back through a transmission line shield 214 , and finally back to the return path conductor 4 . The imaging core 200 components 212 , 214 , 220 rotate inside a catheter sheath by means of a drive motor 30 . The imaging core conductors 212 , 214 are electrically loaded by a transducer 220 . The rotary coupler 100 A comprising the cylindrical surface concentric capacitor 110 and the parallel plate capacitor 120 is used to electrically couple the fixed and rotating components. A drive shaft 32 is mechanically coupled to the rotating drum 112 A and rotating plate 122 A.
[0041] When operating in a send mode the send signal along conductor 2 passes through a transmit/receive (T/R) switch 10 to the conductor 12 leading to an input transmission line 20 . The outputs of the input transmission line 20 are a send signal conductor 22 and a return signal conductor 24 . The conductors 22 , 24 are the inputs to the rotational coupler. The rotary coupler transfers (or couples) electrical signals between the send signal conductor 22 and the proximal end of the catheter transmission line 210 center conductor 202 . The rotary coupler also transfers electrical signals between the return signal conductor 24 and the proximal end of the catheter transmission line shield 204 . This is achieved with two capacitors.
[0042] The send coupling capacitor 110 comprises concentric drums 110 A, 112 A. The return coupling capacitor 120 comprises parallel plates 120 A, 122 A. Regarding the two capacitors, fixed components 110 A, 120 A remain stationary while rotating components 112 A, 122 A rotate with the motor 30 , drive shaft 32 , and catheter imaging core 200 . Input transmission line center conductor 22 electrically connects to drum 110 A, and the send signal on conductor 22 is coupled to drum 112 A which is electrically connected to catheter transmission line center conductor 212 . The input transmission line shield 24 electrically connects to the fixed plate 120 A, and the signal on conductor 24 gets coupled to rotating plate 122 A which is electrically connected to catheter transmission line shield conductor 214 . A radiofrequency (RF) connector (not shown) is used to connect conductors 102 , 104 of the catheter interface module and conductors 202 , 204 of the catheter. Any RF connector can generally be used, but a subminiature RF connector such as an SMB connector is typically used. Consequently, signals on stationary input transmission line conductors 22 , 24 get coupled to the rotating catheter transmission line conductors 202 , 204 .
[0043] The same rotational coupler serves to couple high frequency (>40 MHz) signals generated by the transducer 220 (from ultrasound reflections) back in the reverse (or return) direction. In the return case, signals generated from the transducer 220 are sent to the receiver 8 through the imaging core conductors 202 , 204 and input transmission line input-side conductors 12 , 14 . The rotary coupler capacitively couples the signals on the imaging core proximal conductors 202 , 204 to input transmission line output-side conductors 22 , 24 . The input transmission line 20 outputs the receive signals on input-side conductors 12 , 14 . The signal on conductor 12 is sent to conductor 4 via the T/R switch 10 which would be set for the receive path. Note that the send and receive cases are never allowed to occur simultaneously. A transmit signal is sent to the transducer 220 (with the T/R switch 10 set to send) before the T/R switch 10 is set to receive.
[0044] The diagram of a catheter interface module 2000 B and catheter 1000 B in FIG. 9 is substantially the same as the diagram of the catheter interface module 2000 A and catheter 1000 A in FIG. 8 and hence, reference characters for like elements are repeated in FIG. 9 . A rotary capacitive coupler 100 A comprises a cylindrical surface concentric capacitor 110 having concentric drums 110 A, 112 A and a parallel plate capacitor 120 having parallel plates 120 A, 122 A and is located in the catheter. An RF connector (not shown) is used to connect conductors 22 , 24 of the catheter interface module and conductors 106 , 108 of the catheter. A subminiature RF connector such as an SMB connector is typically used. Signals on stationary input transmission line conductors 22 , 24 are coupled to the rotating catheter transmission line conductors 202 , 204 .
[0045] FIGS. 10-13 show various embodiments of rotary capacitive couplers that may be employed in practicing the present invention. The diagrams of the rotary capacitive couplers, drive motor, and drive shaft in FIGS. 10-13 are substantially the same as the diagram of the the rotary capacitive couplers, drive motor, and drive shaft in FIG. 8 and hence, reference characters for like elements are repeated in FIGS. 10-13 .
[0046] The rotary capacitive coupler 100 B illustrated in FIG. 10 comprises a conical surface concentric capacitor 111 having concentric conical surfaces 110 B, 112 B and a parallel plate capacitor 120 having plates 120 B, 122 B. The output-side input transmission line conductors 22 , 24 are electrically connected to the rigidly fixed conical surface 110 B and parallel plate 120 B. The rotatable conical surface 112 B is electrically connected to conductor 102 and mechanically connected to the drive shaft 32 . The rotatable parallel plate 122 B is electrically connected to conductor 104 and mechanically connected to the drive shaft 32 .
[0047] FIG. 11 shows a rotary capacitive coupler 100 C comprised of two cylindrical surface concentric capacitors 113 and 115 having concentric drums 110 C, 112 C and 120 C, 122 C, respectively. The output-side input transmission line conductors 22 , 24 are electrically connected to the rigidly fixed cylindrical surfaces 110 C, 120 C. The rotatable cylindrical surface 112 C is electrically connected to conductor 102 and mechanically connected to the drive shaft 32 . The rotatable cylindrical surface 122 C is electrically connected to conductor 104 and mechanically connected to the drive shaft 32 .
[0048] FIG. 12 shows a rotary capacitive coupler 100 D comprised of two conical surface concentric capacitors 117 and 119 having concentric surfaces 110 D, 112 D and 120 D, 122 D, respectively. The output-side input transmission line conductors 22 , 24 are electrically connected to the rigidly fixed conical surfaces 110 D, 120 D. The rotatable conical surface 112 D is electrically connected to conductor 102 and mechanically connected to the drive shaft 32 . The rotatable conical surface 122 D is electrically connected to conductor 104 and mechanically connected to the drive shaft 32 .
[0049] FIG. 13 shows a rotary capacitive coupler 100 E comprised of two parallel plate capacitors 121 and 123 having plate pairs 110 E, 112 E and 120 E, 122 E, respectively. The output-side input transmission line conductors 22 , 24 are electrically connected to the rigidly fixed parallel plates 110 E, 120 E. The rotatable parallel plate 112 E is electrically connected to conductor 102 and mechanically connected to the drive shaft 32 . The rotatable parallel plate 122 E is electrically connected to conductor 104 and mechanically connected to the drive shaft 32 .
[0050] FIG. 14 illustrates still another embodiment wherein an IVUS system comprises a rotary capacitive coupler 100 and a rotary inductive coupler 100 -HF. A catheter interface module 2000 C comprises the rotary inductive coupler 100 -HF and the rotary capacitive coupler 100 on a single rotating shaft with two sets of independent electrical connections. The catheter 1000 C comprises a high frequency (less than approximately 30 MHz) transducer 220 -HF and very high frequency (greater than approximately 30 MHz) transducer 220 .
[0051] This invention overcomes drawbacks associated with rotary inductive couplers used in minimally invasive, high-frequency IVUS imaging systems and catheters. In particular, rotary capacitive couplers improve system performance by reducing insertion loss and impedance variation with angular position. The rotary capacitive couplers disclosed heretofore comprise parallel plate capacitors, cylindrical surface concentric capacitors, and conical surface concentric capacitors. A parallel plate capacitor comprises a first rigidly fixed plate and a second rotatable plate. A cylindrical surface concentric capacitor comprises a first rigidly fixed cylindrical surface and a second rotatable cylindrical surface. A conical surface concentric capacitor comprises a first rigidly fixed conical surface and a second rotatable conical surface. The exemplary rotary capacitive couplers can be combined for system performance advantages. Furthermore, a rotary inductive coupler and a rotary capacitive coupler can be used in a two channel IVUS system and catheter for high frequency and very high frequency operation.
[0052] While particular embodiments of the present invention have been shown and described, modifications may be made, and it is therefore intended to cover in the appended claims, all such changes and modifications which fall within the true spirit and scope of the invention as defined by those claims. | An imaging system comprises a catheter having a lumen, a rotatable imaging probe within the catheter lumen including a distal transducer and first and second conductors coupled to the transducer, and a coupler that couples the rotatable first and second conductors to non-rotatable third and fourth conductors, respectively. The coupler includes a rotary capacitive coupler. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/636,785, which was filed on Dec. 16, 2004 of common inventorship and title and which provisional application is hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to surface mounted resistors and more particularly to high power dissipating surface mounted resistors.
[0004] 2. Background Information
[0005] The use of power resistors in electronic circuits is well known. Such products are produced by dozens of vendors, with ratings of a few watts up to thousands of watts, involving hundreds of physical configurations. Over the past 15-20 years there has been significant growth in the use of surface mount components, with power resistors not immune to that trend. Driving this trend has been the desire for manufacturers and consumers to have functionality in ever-decreasing equipment size or, conversely, more functionality in the same size.
[0006] The pressure to lower cost has been an additional impetus since surface mount manufacturing techniques, being highly automated in nature, are particularly conducive to high throughput and high repeatability. Electronic assembly has steadily progressed to where more and more components, previously used only in their through-hole (components mounted with their leads extending through the printed circuit board) version, are becoming available as surface mountable versions.
[0007] This is another way of saying that surface-mount assembly, originally associated with low-power circuits, is increasingly being expected to accommodate higher-power functions. Viewed from a circuit designer's standpoint, surface mount only requires a major space consideration on one side of a printed circuit board while a through-hole part has an impact on available space on both sides of the PC board: on one side for the component itself and on the other for the protrusion of leads. That is to say. a surface-mount component, aside from its many other size and reliability advantages, minimizes the need for what is called “mixed technology: that is, the use of one manufacturing process for one side of the PC board and a different process for components affixed to the other side of the PC board.
[0008] The continued acceleration of such trends in compactness and automation has led to the introduction of surface-mount power resistors by many firms. In the simplest case, the device is a standard resistor chip, with perhaps a larger size, so that it can handle up to a watt. Above that power level, many firms have adapted a mainstay of more traditional through-hole power resistor technology; that is, a winding of resistive wire, to create wire-wound surface mount types.
[0009] U.S. Pat. No. 4,672,358 owned by Ohmite discloses a power resistor with its core of traditional design but with its leads arranged for surface mounting. Similar products are offered by many firms, e.g. Vishay, IRC, KOA, Panasonic. These power resistor s are offered with dissipation up to 5 watts.
[0010] Typically, even though wire wound power resistors are wound “non-inductively,” there is some unwanted residual inductance. In high frequency applications, such inductance is a limitation. The present invention inherently minimizes the inductance.
[0011] In the U.S. Pat. No. 4,672,358 patent, the power resistor is placed down flush with the PC board surface. This is a limitation of the patent and limits the power resistor to about 50% of its stated rating. If the power resistor transmits too much heat to a circuit board, that circuit board will not pass safety-agency rating criteria. For example, a power resistor rated for a maximum temperature of 250 degrees C. (Celsius) might be operating safely at 200 degrees, but the PC board below it, being at perhaps 175 degrees C., is far above its safety-agency rating, which is typically about 100 degrees C. and 150 degrees C. for some types of fire resistant boards. U.S. Pat. No. 5,291,175 describes these considerations.
[0012] Another thermal consideration involves certain types of power resistors used in “dynamic-braking” applications. In such applications, the resistor can be subject to high current for a short period of time. U.S. Pat. No. 5,710,494 describes such applications and the principles involved. In a typical continuous-mode operation, the maximum temperature rating determines the power dissipated. If the temperature rises above that maximum, the resistor may fail. Such a rating can be influenced by the resistor surface area, the ambient temperature and cooling effects of air turbulence in the immediate vicinity of the resistor.
[0013] In a short-duration, high-current mode, however, the power dissipated in a resistor may be much higher that the listed rating and the maximum temperature not reached. This is because other parameters, namely, the mass and specific heat of the resistor control the temperature rise for short duration events. The mass acts like a shock absorber to short bursts of power. Therefore, in short-duration, high-current applications, such as dynamic braking, capacitive-discharge circuits, power supply inrush limiters etc., it is possible to have a small resistor do the job of a much larger one if the relationship of surface area, ambient temperature, air turbulence, pulse-current duration and material mass are understood wherein the temperature rise remains below the resistors rating.
[0014] In cases where it is possible to have the mass, as just referenced, in the form of a thermally conductive metal, such as aluminum or copper, it is possible to obtain substantially higher dissipation in a relatively small resistor assembly. Such higher dissipation is achieved by making use of the very low value of what is called transient thermal impedance, a term long associated with power semi-conductors. International Rectifier Corp. Application Note 949 , entitled “Current Ratings of a Power Semiconductor,” 1999; and a paper by Chan Su Yun, entitled, “Static and Dynamic thermal Behavior of IGBT Power Modules,” dated Jun. 9, 2000 and available on the Internet at: wWw.iis.ee.ethz.ch/csyun/papers/thesis/node71.html are incorporated herein by reference. These references describe the principles involved.
[0015] A paper by the present inventor entitled, “Cooling a High Density DC-DC Converter Impacts Performance and Reliability,” published in PCIM Magazine (now Power electronics magazine), November 1999, pages 60-66 describes in detail heat removal from a power semiconductor chip whereby that heat travels from the chip through a series of barriers on its way to an ultimate cooling medium. This reference is also incorporated herein by reference. The carefully configured heat removal system described in this paper is used in preferred embodiments of the present invention to maximize power handling in both continuous and high-power transient modes.
SUMMARY OF INVENTION
[0016] In light of the limitations of prior art and other advantages described herein associated with surface-mount power resistors, the present invention provides reduced inductance, minimum heat transfer to mounting circuit boards, increased power-to-surface mount footprint ratio, increased short-duration overload rating, improved reliability and reduced cost.
[0017] In preferred embodiments, the resistive element has, not a wire or metal foil strip typical of conventional power resistors, but rather of a silk-screened layer of resistive film (called thick film) on a thin (typically under 025′) aluminum oxide (alumina) substrate, with solderable termination pads at either end of the resistor film. The use of such technology for individual, commercial surface mount chips has been common for over 25 years.
[0018] For the sake of clarity, in deposited film resistor technology there are two principle methods: thick film and thin film. They are both “thin” but one is much thinner than the other. In the resistor industry, thick film typically refers to a process in which a resistive film paste, generally no more than 0.001-0.003″(25-75 microns) in thickness, is silk screened onto a substrate, after which it is fired, in a controlled but not vacuum environment, into a rigid, glass-like coating. Basic thick-film resistor technology is very well known, having been used for over 40 years.
[0019] With thin-film technology, a very thin film (typically no more than a few microns) is deposited, under vacuum conditions, onto a substrate. Thin-film processes are generally associated with much finer tolerances and more specialized materials. Thin film technology, employing such techniques as metal-vapor vacuum deposition and sputtering, has been in use with increasingly sophisticated processes, for over 50 years.
[0020] The termination connections may or may not be brought over the edge of the resistor onto the back-side of the chip depending on manufacturing preferences. If it is brought around to the back-side, the chip is know as having “wrap-around” metallization. Well over 95% of such chips today employ such wrap-around metallization, a technique for best compatibility with solder mounting onto a PC board.
[0021] With one of the larger versions of a conventional thick film resistor chip, measuring 0.250″ by 0.125″ (called a 2512 chip), operating under load and generating some heat, that heat removal is mostly through a) the end terminations, which are soldered to the PC board, and to a lesser degree by b) the surface area of the chip exposed to the ambient air (a combination of radiation and convective cooling).
[0022] With the chip size as noted, it is difficult to operate at much more than a watt before the maximum rating of the resistive film, about 150 degrees C., is exceeded, or before the solder terminations approach their melting point. It should be emphasized that there would no fundamental power limitation of such a chip if the heat were appropriately removed with 100% efficiency. It is simply that there is not enough surface area exposed to the surrounding air or enough heat conduit area through the solder pads. Heat leaves the chip just like water in a drain-pipe. If the pipe is too small, the water cannot be quickly removed.
[0023] Therefore, for an easier understanding of the principles involved, the chip can be thought not to have a fundamental limitation, An objective of the present invention is to maximize the transfer of heat to the ultimate cooling medium, the surrounding air. The first step is to lessen the first heat removal barrier. It has been noted that with the standard wraparound resistor, the heat removal is to the PC board through the solder pads at either end and, then, from the surface of the PC board to the air. In a preferred embodiment of the invention, the standard wraparound approach is replaced by one which consists of metallizing the back-side of the chip opposite to the resistive film and then soldering that metallized surface to a thermally conductive metal such as copper or aluminum.
[0024] In this manner, there is an extremely effective heat removal path, only about 0.020″ long, from the heat-generating resistive film to the metal surface. Furthermore, all portions of the resistive film are only 0.020″ away from the metal surface, unlike with a wraparound configuration in its traditional method of usage, where most of the heat has to travel from the center out to the edge before it can exit. In other words, the best heat transfer comes from metal-to-metal, molecularly bonded contact.
[0025] The metal surface to which the chip is soldered is actually part of an extruded aluminum structure, which has an overall surface area much greater than the chip itself. Consequently, it acts as a surface area “amplifier.” The heat from the chip is rapidly transferred to a metallic area, which can typically be over 50 times greater than the chip.
[0026] As a result, when air is passed over the aluminum structure, the air can remove far more heat than if only passing over only the small surface area of a 2512 chip. This is the basic theory of a cooling fin. In preferred embodiments, the present structure with the mounted chip has through slots or holes that provide added surface for dissipating heat to cooling air, especially air that is flowing through the slots or holes. Also, in a preferred embodiment of the present invention the structure is designed with added mass that enhances the resistor's short-duration power handling.
[0027] As earlier noted, the practical power-handling capability of the resistor chip is directly related to its capacity to effectively remove heat from the chip and prevent the resistive film or its contact terminations from reaching temperatures where undesirable electrical or metallurgical changes occur. That heat removal effectiveness is directly related to the surface area (the cooling fin) of the resistive film and inversely proportional to the thickness of the alumina substrate (internal heat takes time to reach the surface for cooling). The heat removal effectiveness is further influenced by the method of bonding the alumina to the metallic heat sink and the subsequent method of transferring heat from the heat sink to the surrounding air.
[0028] The heat removal from the metallic termination areas is important due to possible thermal fatigue of the terminations. This heat removal is influenced by the method of making connections to those terminations. For example, if the resistor is soldered to a PC board, there is, because of the larger cross-section of the thermal interface, a better metallic heat-removal path than if there were simply semiconductor-type wire bonds to the chip. With wire bonds, a connection can be made, which is excellent from an electrical standpoint, but under most conditions, the cross-section of the wire is insufficient to contribute meaningfully to heat removal.
[0029] The paper, “Cooling a High Density DC-DC Converter Impacts Performance and Reliability,” noted earlier, describes in detail a) the process of heat transfer from a dissipative source such as the resistive thick film, through multiple materials and interfaces, and then ultimately to the surrounding air, and b) how that heat travel path can be modeled as a cone, with the apex of the cone being the source of dissipation. U.S. Pat. No. 6,515,858 describes methods for implementing the principles involved in the conical path of heat removal from a dissipative point source to surrounding air.
[0030] In as preferred embodiment, the resistor chip is soldered to the non-anodized but solderable surface areas of an extrusion. The heat travels from the soldered interfaces throughout the volume of the extrusion metal, after which the surfaces of the extrusions pass heat to the surrounding air, which may be static or moving. The extrusions also have integral details which serve both as a conductive path to a printed circuit board and as an extra heat-removal mechanism for the chip terminations to ensure that those terminations remain at a lower temperature than the resistive film. In an embodiment there is an interference fit between the chip and the extrusion structure that promotes heat removal.
[0031] In a preferred embodiment, the extrusion is made up of a pair of mirror-image parts which are electrically isolated from one another to ensure that, electrically, there is only the resistor value between one termination and the other. As part of this embodiment, the back-side metallization of the chip, as well as the final position of the extrusion pair, exhibit a narrow stripe where there is no electrical conductivity. This insulated area is controlled to guarantee a voltage or dielectric strength rating which might typically be in the hundreds of volts.
[0032] It has been noted that the extrusion parts are such that contact is made to the chip in a way which also serves to remove some heat. It is known among resistor chip manufacturers that in a typical surface-mount application, the center of the chip is usually much hotter than the ends near the terminations, with the elevated-temperature point being known as the “hot spot.” When the back-side of the chip is appropriately bonded to a heat sink surface, that hot-spot effect can be lessened because all portions of the resistive film have essentially the same distance to travel to the heat sink. Theoretically, this would mean that the chip could be operated at higher power, likely up to more than the normal 150 degrees C rating, since 175 degree C. operation would still be well below the original processing temperatures for the chip.
[0033] An important reason for not letting the terminations overheat is that the terminations could be weakened. That is, in the presence of repeated extreme temperature cycling, there could be thermal fatigue of the solder on those terminations. The presence of substantial metallic mass in the contacts to those chip solder pads terminations removes heat in those specific areas so that just like a PC board mounted chip, the ends are cooler than the center. Nevertheless, the presence of the hot spot is not an issue as long as it is taken into account in the rating of the resistor assembly. An important objective of the present invention is to prevent the termination temperatures from becoming the limiting factor in the power rating of the assembly. In other words, it is an objective of the present invention for the terminations and the resistive film to have comparable safety margins.
[0034] The extrusion pair also has integral details such that there are electrically connective terminations comparable to those referred to in the industry as J-lead terminations. The final power rating of the assembly is determined by the thermal resistance (the total as combined for all heat paths) from the resistive film to the surrounding air. The principles of thermal resistance analysis are very familiar to those skilled in the use of power semiconductors and similar dissipative components requiring heatsinks or air cooling and need not be discussed in detail here.
[0035] Suffice it to say that thermal resistance is measured in degrees C. per watt. That is, for every waft of power in the chip/extrusion assembly within a given static or moving air environment, the resistive film temperature will increase by a specified number of degrees in accordance with the design.
[0036] In preferred embodiments, the total thermal resistance is most influenced by a) the individual thermal resistance from the resistive film, through the alumina, to the extrusion metal, b) the surface area of the resistive film and c) the surface area of the extrusion metallic area exposed to the surrounding air. Having one be superior while another is poor would be of no benefit since they are additive. Therefore, it is an objective of the present invention to reflect the point of diminishing return in optimizing (minimizing) any given contributor to thermal resistance relative to the overall size, power and cost objectives.
[0037] While the three largest contributors to thermal resistance have just been noted, there are others as well, although individually they are less influential. Nevertheless, as a collective contributor they cannot be ignored. They include the cross-sectional thickness of the extrusion, the thickness of the alumina, characteristics of the chip-to-extrusion thermal interface, the extent to which the extrusion profile restricts air velocity through it, the air velocity and direction and, finally, metallic distance from the bottom side of the resistor chip to the distal points of the extrusion.
[0038] The extrusions are initially fabricated as thin wall aluminum components and are selectively tin plated so as to be compatible with a solder process. While aluminum is not normally solderable, there are well-established techniques in the plating industry for preparing the aluminum to accept a conventional solder process.
[0039] In the assembly process, an extrusion piece is pushed onto each side of the resistor chip making an interference contact that holds the chip in place. Before or after mounting the chip, solder paste, for the first proposed embodiment, can be applied to the extrusion areas where the chip is to be positioned and soldered. It is possible, with appropriate solder pre-plating of the extrusion, to eliminate this solder paste step. After mounting, the extrusion fingers are forced against the pair of resistor chip contacts while the back-side of the chip is pressed against the pair of extrusion surfaces. It will be clear to those skilled in such design of small assemblies that a variety of similar methods can be applied to position the extruded contact members close enough for soldering to the chip terminations.
[0040] When this chip/extrusion assembly is passed through an appropriate belt furnace or comparable elevated temperature environment, the solder paste (or pre-applied solder coating) or other appropriate solder locations melt and the chip metallized area becomes bonded to the combined flat surfaces of the extrusions. Similarly, the contact fingers become bonded to the chip terminations.
[0041] After assembly, an adhesively backed rectangular label or comparable flat, thin material is affixed to the top of the extrusion pair so that the surface becomes compatible with the vacuum pickup mechanism typical of surface mount pick and place equipment. Although the original chip had its own pair of contacts, that electrical connection method is now transferred down to the lower curved portion of the extrusion which is designed to serve as the J-lead surface mount contacts, a standard industry surface mount component technique.
[0042] The addition of the extruded pieces can decrease the overall thermal resistance from the chip to the convective air-flow ambient by typically a factor of 10 from what the chip would exhibit by itself. Furthermore, as earlier noted, the extruded pieces provide not just increased surface area for cooling but also a thermally conductive mass which can significantly decrease what is called transient thermal impedance, the determinant of short duration overload capability.
[0043] In other words, for short durations, such as a few seconds, it is mass rather than surface area which can most significantly determine power capability. For a fraction of a second or even a few seconds, a tiny heat sink can act like a heat sink 10 times its size. This means that an assembly containing a pair of paralleled 2512 resistor chips, which might only handle one watt in a standard surface mount configuration, might handle up to 10 watts or more with the proposed embodiment on a continuous basis and, for a second or two, as much as 30 to 50 watts before the extruded pieces heat sufficiently for the resistor film and the terminations to reach their temperature limit.
[0044] Because the complete product is assembled essentially in one pass through a reflow oven of established temperature profile, it is expected that the approach will provide improved repeatability and reliability lower cost and compatibility with visual inspection. With the final configuration, it is anticipated that a power density of more than 50 watts per square inch of PC board footprint is achievable, while still maintaining a height under 0.5 inch, a de facto standard height limit for many surface mount PC boards, even those involving substantial amounts of power.
[0045] In another preferred embodiment, the resistor chip, rather than having electrically separate back-side metallization, may be a standard wraparound type. In such a typical resistor, the top-side pads are normally only used to make connection to the resistor film. The metallization is continued from those connective points, over the side of the chip, and around onto the back-side, so as to transfer the pair of top side resistor contacts to the bottom side. Typically, the final connective metallized pads on the bottom side are slightly larger than the top-side pads to more readily facilitate subsequent surface mounting onto a PC board. However, they need not cover most of the bottom of the chip as in the first proposed embodiment since the back-side in this embodiment does not depend on a soldered interface for heat transfer.
[0046] In this embodiment, the solder which would have been the thermal interface between the chip and heat sink, as in other embodiments, is replaced by a thin layer of phase change material, a specialized paraffin material filled with thermally conductive microscopic particles. The material, normally existing as a solid, melts at a predetermined temperature and fills the microscopic voids which invariably exist between two mated surfaces.
[0047] Such voids, which might be no greater than 0.0001″ (one ten-thousandths of an inch) in size, can significantly affect heat transfer if not substantially eliminated.
[0048] The material essentially memorizes the voids and when cooling, retains, on its surfaces, the shapes of those voids, regardless of how many subsequent power cycles occur.
[0049] Until the 1990's, metallurgical bonding, such as soldering, was widely accepted as the best method of reducing thermal resistance. Where soldering was not practical, thermal grease has been generally considered the next best method, although the use of such a material has a number of process related difficulties. While thermal grease is indeed an excellent interface material, it can exhibit poor results if not applied in the thinnest possible void-free manner.
[0050] For power semiconductor applications there has for some time been increased usage of fixed-thickness elastomer-based materials as a grease replacement option. While not as good as grease, they are more repeatable in their result and easier to implement, but again they can exhibit poor results if not applied with appropriate pressure. More recently, however, the phase change materials have in many instances shown superior heat transfer, less vulnerability to manufacturing control variations and, when used without a plastic tape to achieve electrical insulation, can begin to approach the thermal conductivity of a solder interface.
[0051] U.S. Pat. Nos. 6,620,515 and 6,764,759 describe the principles and general applications associated with the use of phase changes materials for heat removal in electronic components. Prior preferred embodiments illustrate three differences. First, the chip is of the standard wraparound type instead of having electrically isolated top and bottom surfaces. Secondly, the extrusion pair surfaces intended for most heat transfer, which had been selectively absent of anodizing and plated for solderability, are maintained as anodized surfaces. The anodic coating provides substantial electrical isolation so that even when the bottom side wraparound metal of the chip touches the heat sink surface, the chip is electrically isolated by the anodic film, which actually is a very hard aluminum oxide film with typical thickness of 0.001-0.003 in this application. Thirdly, the solder is replaced by the phase change material.
[0052] The phase change material is superior to conventional adhesive bonding of the chip in that it is less prone to separation during temperature cycling. It is superior to a filled-elastomer interface (having such trade names as Silpad) because, in conjunction with the anodic oxide coating, can be an electrically insulative heat-transfer medium less than a tenth as thick.
[0053] It is far superior to thin, coated thermoplastic insulators (having such trade names as Isostrate) because the anodic oxide coating is more than 10 times as thermally conductive as the thermo plastic materials for any given thickness. Also, this material is in a viscous state when warm, due to applied power, and there is always some compressive force created by intimate contact of the chip to the structure in the assembly, that results in a chip-extrusion thermal interface that approaches the molecular-bond performance of a soldered interface.
[0054] The option represented by the second embodiment provides the ability to take advantage of the off-the-shelf availability and wide variety of chip types associated with wraparound types. While not thermally equivalent to a soldered interface, the second embodiment nevertheless provides a very cost effective option when appropriately employed and in some cases some offers actual mitigation against thermal fatigue effects.
[0055] It will be apparent to those skilled in the use of adhesives in thermal management of microelectronic components that certain epoxy type adhesives, if filled with thermally conductive ceramic powder, having appropriate viscosities, can, if applied judiciously, approach the thermal conductivity of the phase changes materials. The choice of material is likely to be influenced by the power level and extent to which already existing process techniques favor one over the other.
[0056] It will be appreciated by those skilled in the art that although the following Detailed Description will proceed with reference being made to illustrative embodiments, the drawings, and methods of use, the present invention is not intended to be limited to these embodiments and methods of use. Rather, the present invention is of broad scope and is intended to be defined as only set forth in the accompanying claims.
DESCRIPTION OF DRAWINGS
[0057] FIG. 1 is an exploded assembly drawing illustrating the piece parts for the complete assembly;
[0058] FIG. 2 is an isometric drawing illustrating a pair of resistor chips as installed on the assembly of FIG. 1 ;
[0059] FIGS. 3A and 3B are perspective views showing the complete assembly as mounted on a circuit board; and
[0060] FIG. 4 is an assembly drawing of a complete assembly, mounted on a circuit board, and positioned for best use of convective air flow cooling;
DESCRIPTION
[0061] In FIG. 1 is shown a resistor chip 1 , typically 0.025″ thick, having a resistive film 40 , topside solderable terminations 2 . On the reverse side is a solderable metallization pattern 3 which covers the entire surface except for a narrow strip 4 which breaks the metallization into two distinct areas. The thickness of the narrow isolation between the metallizations 2 and 3 could typically be 0.030-0.050″, or a distance sufficient to safely provide several hundred volts of dielectric isolation.
[0062] Each of the top-side metallizations 2 wrap around 42 the side and connects with the back-side 3 below it. In addition, the pair of bottom side metallized areas 3 need not be as large since they would play no role in heat transfer or solder attachment. Consequently, the space 4 between them, rather than being a narrow space as noted, can occupy most of the area on that surface, in a manner common to most commercial wraparound chip designs.
[0063] In other embodiments the space 4 may contain a resistive film that would be in parallel to the resistive film 40 . In yet another embodiment there may be no wrap around where the metallization areas 2 and 3 would be electrically isolated.
[0064] Also shown are a pair of thin-wall aluminum extrusion sections 6 and 5 , each of which is a mirror image of the other. This pair of extruded pieces is designed to hold one or more chips. The extruded pieces 5 and 6 are pushed 30 onto each side of a resistor chip 1 such that the flat sections 22 of the extrusions 5 and 6 are against the backside metallizations 3 of the chip and curved contact fingers 7 are pressed against the chip terminations 2 . When the assembly is passed though a reflow oven the metallizations 2 and 3 on the chip becomes soldered to the extrusion surfaces and the surfaces 11 , as described below will be soldered to a printed circuit board. In this way the electrical contacts of the resistor or resistors will make electrical contacts with runs on the printed circuit board.
[0065] The present invention is described in detail around a mounted film resistor, but, virtually any chip arranged for surface mounting could be used to advantage with the present invention. Certain dimensions of the extrusions 5 and 6 may be altered to accommodate any such chip.
[0066] In the second embodiment the soldering of the extrusion surfaces 11 to the printed circuit board is the same. However, the chip is not soldered to the extrusion surfaces. Instead, the two extrusion pieces to the chip, the extrusion surfaces meant for contact with the chip are coated with phase change material. During reflow soldering, the phase change material melts and the moderate compressive force of the extrusion surfaces to the chip retains the chip in place. The fact that the phase change material is in a liquid state at that time allows even more intimate contact than if their were a thermal grease interface. The liquid material fills in the microscopic inter-surface voids and that void-free condition remains after the unit cools.
[0067] Each extruded section has a ridge 8 to set alignment as to how far the extrusion can be pushed onto the chip, thereby ensuring that the two extrusions, after being pushed onto either side of the chip, are not in mechanical or electrical contact but yet are close enough to ensure the majority of the back-side of the chip is in contact with extrusion surfaces for heat transfer. Because miniature extrusions and resistor chips can be routinely manufactured with dimensional tolerances of only a few thousandths of an inch, the proposed embodiment can be assembled with a high degree of precision and repeatability.
[0068] Being of appropriately anodized aluminum, the extrusions 5 and 6 have surfaces which are not electrically conductive except for solderable areas. It is known to those skilled in the art that the thin aluminum oxide coating of an anodized aluminum surface has a diamond-like hardness and can exhibit well over 500 volts of dielectric isolation, and, with a special process called “hard anodizing” (thicker than conventional anodizing), provide several thousand volts of electrical isolation.
[0069] A label or similarly thin adhesive-backed material 9 is placed on top of the extrusion pair 5 and 6 after final assembly. It is meant to bridge the gap between the two extrusions and result in a complete surface without the discontinuity which would otherwise exist because of the air gap between the two extruded sections. The complete surface is desirable so that the vacuum pickup apparatus associated with surface mount assembly can maintain that vacuum during pickup of the component. With a discontinuity, the vacuum would not be maintained and alternate methods of component pickup would be required. Such alternate methods are available but would be a significant reduction in the options available to a manufacturing process.
[0070] The lower edge 11 of the extruded sections is plated for solderability so as to function as the surface-mountable contacts for the component. This configuration provides such contacts while still ensuring there is air transport space for cooling purposes under most of the components, particularly under the chip area.
[0071] FIG. 2 depicts a simplified curaway view of a) the final assembly with two chips 1 and 1 ′ installed and without the material 9 . The chips 1 and 1 ′ are intsalled from one end of the extrusions, but the extrusions may be long enough to accept many chips.
[0072] FIG. 3A shows a printed circuit board 12 with solderable pads 13 to receive the surface mountable component assembly 52 with the material 9 covering the extrusions. FIG. 3B shows the component 52 after surface mounting. A resistor chip 1 is shown mounted.
[0073] FIG. 4 shows a surface-mounted assembly 52 in relation to airflow direction 14 to achieve best cooling performance. In this direction air passes over but also though the unit. If air were to be at a right angle to this direction, or perpendicular to the top surface, there would still be substantial cooling but there would be negligible air passing through the unit, with a potential 10% 20% reduction in cooling effect, accompanied by a corresponding reduction in maximum power capability.
[0074] With very small surface-mount components, there are very clear industry guidelines for component orientation for surface-mount reflow soldering so as to prevent process anomalies.
[0075] However, with the preferred embodiment shown, the potential spacing, outgassing, or solder bridging factors (common in most soldering processes) do not exist. Consequently, the PC board can be designed at the outset with the component in the best orientation relative to airflow, with far less concern about manufacturing process nuances.
[0076] It should be understood that above-described embodiments are being presented herein as examples and that many variations and alternatives thereof are possible. Accordingly, the present invention should be viewed broadly as being defined only as set forth in the hereinafter appended claims. | A surface mountable resistor chip assembly, containing an integral heat sink, convective cooling provision exhibits higher continuous-mode power ratings than prior art surface mount resistors having comparable printed circuit board footprints. The preferred embodiments are also configured so as to reduce transient thermal impedance in a manner to exhibit increased power rating under short duration overload conditions. The assembly includes a housing with passages, holes or slotted openings, for the chip assembly and for air flow therethrough, and electrically conductive paths to bring the chip electrical connections out to pads on the housing arranged to make electrical connections to a printed circuit board. | 7 |
FIELD OF THE INVENTION
The present invention relates to water management systems for collecting, storing and distributing runoff water for comprehensive use.
BACKGROUND OF THE INVENTION
Water collection systems for storing runoff water from roofs have been proposed for varying usages. Such systems permit the storage during periods of heavy precipitation for use to supplement water utility usage during dryer periods. Both potable water and agricultural uses have been proposed and the systems tailored to the specific needs. Generally, the water is collected at the gutters from the roof runoff and directed through downspouts and conduits to an underground storage tank. The collected water may be purified and used for potable water as disclosed in U.S. Pat. No. 6,663,769 to Hosoya, or used for irrigation as disclosed in U.S. Pat. No. 5,234,286 to Wagner.
There are many areas, however, where the rainfall is rather steady throughout the year and where the need for singular use collection systems is not compelling, but where in the interests of conservation utilitarian uses are desirable. The average homeowner has ongoing and seasonal yard care needs for lawns, gardens, shrubbery and other discrete areas having intermittent water needs. In addition to watering, these require periodic attention with fertilizers and other additives that vary throughout the course of the year. U.S. Pat. No. 4,934,404 to DeStefano discloses a water collection system wherein a port in a downspout is used for the addition of fertilizers and nutrients for an irrigation field. Inasmuch as such additives are often granular and generally concentrated, there is no assurance when and if they will transit the connecting conduit to the reservoir thereby rendering the concentration uncertain. Further, there is no assurance of uniform mixing inasmuch as the additives are deposited on the reservoir water without mixing. Further, only modest screening of the runoff water is provided by a screen at the eaves, and accordingly finer sediment is transferred to the reservoir where it will accumulate and contaminate the contents. The construction of the reservoir makes removal of the accumulations difficult with no solution proposed. As a result, other than providing watering capability, the ability of the system to provide reliable landscape additives is problematic.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a comprehensive water runoff collection system having a controlled addition and mixing of soluble additives enabling through multiple formats the reliable distribution to select portions of the landscape. Therein, the runoff water from the roof of a structure is initially routed to an accessible premix catch basin whereat any debris and sediment is settled for convenient periodic removal. The premix catch basin is connected with a main buried reservoir by a connecting conduit including an inline filter for removing remaining suspended sediment, thus ensuring that only filtered water is transferred thereto. Water from the reservoir is transferred by a submersed pump to a pressure manifold having plural valved outlets enabling use in varying modes, including fixed sprinkling systems, mobile hose outlets, and local structure water applications. The manifold further includes an outlet connected to a mixing head in the premix catch basin for the preliminary mixing of additive solutions, without requiring runoff water from the roof. This outlet also assists in the cleaning of accumulations from the premix catch basin. The manifold further includes mixing jets in the main reservoir for providing agitation for a uniform additive solution. Throughout the change of seasons, the desired additives can be added for all aspects of landscape care. Seasonal changes in the additives can be added to the residual contents compatibly. To prevent dilution, a bypass line is provided at the premix chamber to divert runoff water after an additive solution has been prepared.
DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the invention will become apparent upon reading the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic diagram of a water collection and distribution system in accordance with an embodiment of the invention;
FIG. 2 is a schematic diagram for the distribution manifold of FIG. 1 ;
FIG. 3 is a schematic diagram of the control system for the pumps in the collection and distribution system; and
FIG. 4 is a top view of the catch basin of the collection and distribution system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, FIG. 1 illustrates a water collection and distribution system 10 providing water and additive solutions for use in maintenance activities around a yard 12 surrounding a structure 14 . The system 10 collects water running from the roof 15 of the structure 14 into a gutter system 16 discharging into one or more downspouts 18 . A preliminary filter screen may be placed at the top of the downspout for partially eliminating debris from the system. The system may be used in connection with pitched or non-pitched roofing systems for commercial and residential structures using conventional components.
Water flowing through the downspout 18 is routed at coupling 19 to supply conduit 20 below the surface of the surrounding ground level 22 of the yard and having an outlet at a buried premix catch basin 24 . The catch basin 24 has a bottom upwardly opening cavity covered with a removable hatch 28 . Runoff water from the roof may contain debris that is settled at the bottom catch basin. The hatch 28 may be opened for the periodic removal of the settled debris. The hatch 28 may be solid and generally flush with the surrounding ground or grated for accepting ground runoff water. Catch basins suitable for use are commercially available.
The catch basin 24 has an outlet fluidly connected with a collection reservoir 30 buried below ground level by connecting conduit 32 . Referring additionally to FIG. 4 , a filter 34 is connected to the inlet of the connecting conduit 32 for the filtering of remaining particulates in the water. The filter 34 is located in the catch basin 24 at the inlet of the connecting conduit 32 for facilitating the servicing thereof. A branch or bypass conduit 36 has an inlet located in the catch basin. A plug 38 is insertable into either the inlet of the connecting conduit or the bypass conduit to selectively block flow therethrough. When it is desired to route the runoff into reservoir 30 for filling, the plug 38 is removed from conduit 32 and inserted at the bypass conduit 36 . When it is desired to block flow to the reservoir when a prepared mixture is being held, the plug is switched to the conduit 32 and the runoff is directed to the bypass conduit 36 . The bypass conduit 36 has an outlet connected to a drainage conduit 40 . The drainage conduit 40 has an entrance at the top of the reservoir 30 and an exit 42 on a grade 44 at a level below the top of the reservoir 30 .
The reservoir 30 is buried below ground level 22 . The reservoir 30 is formed of a suitable water resistant material, such as fiberglass or plastic, having a capacity suitable for handling the anticipated roof runoff. The reservoir includes a pair of manholes or hatches 46 , 48 below ground level. Personnel can enter the reservoir through the hatches for installation and maintenance. A main submersible pump 50 is installed in the reservoir and vertically positioned, by suitable means, adjacent the base of the reservoir 30 . The pump 50 includes an outlet connected to a check valve 52 and through supply conduit 54 to a pressurized distribution manifold 56 . A secondary overflow pump 60 is installed in the reservoir and vertically positioned by suitable means, adjacent the upper portion of the reservoir. The overflow pump 60 is connected by distribution conduit 64 to a distribution head 66 and is operative to distribute excess water to the ground. The pump 60 may function in parallel with the drainage conduit 40 to limit fluid level in the reservoir under high runoff conditions or to function in lieu of the drainage conduit when an appropriate grade is not available.
A hand pump 68 is provided for manually pumping water from the reservoir for intermittent needs. The hand pump 68 is connected by hand pump conduit 69 to a foot valve strainer 70 and check valve 72 adjacent the base of the reservoir 30 .
A mixing head 74 is disposed in the catch basin 24 and connected with the distribution manifold 56 by branch line 76 . The mixing head 74 supplies water for cleaning and mixing as described below. A jet mixer 78 is disposed in the reservoir 30 and connected to the distribution manifold 56 by branch line 79 for supplying water for agitation and mixing, also as described below.
Referring to additionally to FIG. 2 , the distribution manifold 56 is fluidly connected with supply conduit 54 at coupling 80 . The distribution manifold 56 may be located interior or exterior of the structure 14 . For control of fluid pressure, the main line 81 of the manifold 56 includes a pressure tank 82 , pressure relief valve 84 , automatic on/off and low-pressure cutoff switch 86 and pressure gage 88 . Branch lines 90 , 92 , 94 , 96 , and 98 are connected in parallel with the main line 81 . Each branch line includes a manual control valve. Branch line 90 is connected with line 76 to the mixing head 74 . Branch line 92 is connected with line 79 to the jet mixer 78 . Branch line 94 is connected to an outlet 110 for “mobile” use in connection with a hose for variable location watering. Branch line 96 is connected to a “fixed” location application, such as a sprinkler on irrigation system 112 . Branch line 98 is connected to an outlet 114 for “local” use at the structure 14 .
Referring additionally to FIG. 3 , the pump 50 is connected to a 220 volt power supply 120 . The pump 50 is controlled by pressure switch 86 for operation between high and low line pressures and cutoff if the pressure drops below a determined level. The pump 60 is connected to a 110 volt power supply 121 and controlled by float switch 122 associated with the float 62 . A manual cutoff switch 124 is provided for disabling pump operation.
The present invention thus provides a system for comprehensively utilizing runoff water. The system may be used for the collection of filtered water in the main reservoir for delivering water from the manifold 56 for “local” use through line 98 at outlet 114 , “mobile” use 110 through hose line 94 , and “fixed” watering systems 112 through line 96 . If during such accumulation excessive water is presented to the reservoir, the excess is removed by pump 60 and/or drainage line 40 thereby eliminating hydrostatic conditions leading to leakage or reservoir rupture. When fertilization or other additive treatment for landscape maintenance is desired, the desired additive is deposited in the premix catch basin 24 , and the premix line opened to solubilize the additives for transfer to the reservoir and the mixing jets 78 opened to uniformly mix the solution. To maintain the desired concentration, the plug in the catch basin is opened for transferring any incoming water to the discharge line 36 . The additive solution may thereafter be dispensed according to the desired application form, using the spigot, hose or irrigation system. When a revised formulation is desired, the mixing is repeated with the new formulation generally being compatible with the residual solution in the reservoir. To ensure high purity in the reservoir, the catch basin may be cleaned periodically and the mixing head used for flushing. The filter screen may be serviced or replaced as necessary.
Having thus described a presently preferred embodiment of the present invention, it will now be appreciated that the objects of the invention have been fully achieved, and it will be understood by those skilled in the art that many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the sprit and scope of the present invention. The disclosures and description herein are intended to be illustrative and are not in any sense limiting of the invention, which is defined solely in accordance with the following claims. | A water collection and distribution system for yard maintenance includes a buried reservoir for collecting water from the roof of a structure and a submersed pump in the reservoir for supplying contained water to a pressurized manifold having outlets available for yard maintenance activities. One of the outlets is connected with a premix catch basin upstream of the reservoir in which additives may be mixed for storage in and dispensing from the reservoir. Another outlet is connected to spray nozzles in the reservoir for agitating the additive mixture. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of international application PCT/EP2003/013263, filed 26 Nov. 2003, and which designates the U.S. The disclosure of the referenced application is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a closing member for compressed air carrying polygonal tubes of the type used as a mounting rod for the drafting system in a yarn spinning machine.
[0003] In such spinning machines, pneumatically loadable top roller support and weighting arms are used, which are secured by means of brackets to a mounting rod of the machine. The mounting rod is hollow and serves at the same time as a compressed air delivery line. A drafting system of this type is described, for example, in DE 198 29 403 A1.
[0004] DE 198 30 048 A1 discloses a mounting rod that is formed from polygonal tube sections, with each tube section being provided at its ends with closing members. A mounting rod that is composed of individual tube sections permits a modular construction of the mounting rod and compressed air supply for spinning machines of different lengths. The closing members are inserted in a sealing manner into the ends of the polygonal tube sections. Between the polygonal tube sections, the compressed air is conducted through a connecting tube section which interconnects the closing members of two adjacent sections.
[0005] Sealing of non-circular hollow sections with elastic sealing elements, such as O-rings with a circular cross section, or with special section rings, presents problems, inasmuch as irregularities of the special section of the sealing element causes in the latter only a certain equalization of internal tension, without the sealing element filling all zones of the hollow section in a uniform and sealing manner. It is therefore preferred to use in the case of polygonal hollow sections, pasty sealing substances of a suitable viscosity, which must completely fill a sealing channel that is formed by the hollow section and an inserted sealing element. It is however difficult to fill the sealing channel evenly and completely, as well as in a process safe manner in the case of series production. This requires a great expenditure for production and testing. The sealing effect is often not stable for a long duration because of the aging behavior of the sealing substance and because of operational stress, for example, as a result of pressure changes. Thus a reliable, lasting sealing is not ensured.
[0006] If leakages occur in operation, sealing elements of the described type are hard to disassemble and cannot be reused. It is therefore often necessary to exchange the entire special section tube length. Likewise, the sealing substance is able to only a very limited extent retain the sealing element in the required position against the inner pressure in the special section tube. This requires additional special measures, for example, the installation of pins for securing the sealing element against axial displacement.
[0007] If an adhesive is used as sealing substance to increase the hold of the sealing element in its position at the end of the polygonal tube, it will be difficult and costly to disassemble the closing member. In this case, the closing members and, possibly, even the polygonal tube will no longer be suited for immediate reuse.
[0008] At their ends, the polygonal tubes are supported in recesses of brackets that are also known as stands, and secured in position by means of screw connections. To this end, a mounting screw extends through the special-section tube in its end region, which also mounts the respective closing member. By tightening the mounting screw, the polygonal hollow section may undergo elastic or plastic deformations, whereby the sealing effect is additionally put at risk.
[0009] Based on the foregoing state of the art, it is an object of the invention to overcome the above limitations and deficiencies of the known closing members.
SUMMARY OF THE INVENTION
[0010] The above and other objects and advantages of the invention are achieved by the provision of a closing member which is configured for being inserted in an end of a compressed air carrying polygonal tube on a yarn spinning machine, and which comprises an elastic sealing element, and with the closing member being configured such that it axially biases in its inserted state the sealing element, whereby the sealing element expands so as to seal the closing member relative to the polygonal tube.
[0011] The closing member of the invention seals the polygonal tube in a reliable and stable manner for a long duration. It is no longer necessary to secure it in addition, for example, by means of formfitting retaining pins against displacement by the air pressure that builds up in the interior of the polygonal tube, since the closing member is adequately secured in a force-locking engagement, when its sealing function is activated. In comparison with closing members of the known prior art, assembly and disassembly of the closing members are facilitated. The closing members and polygonal tubes are reusable, without having to perform additional labor, such as, for example, cleaning.
[0012] A closing member is constructed such that compressed air is allowed to flow from the polygonal tube through the closing member and into the closing member of an adjacent tube. This permits applying axial pressure to the sealing element in a uniform manner, and achieving a reliable sealing effect.
[0013] The closing member preferably comprises an end piece and a counterpart with the sealing element being constructed and arranged between the end piece and the counterpart. This permits sealing and securing at the same time, after the closing member has been inserted into the polygonal tube. It is also easy and simple to release the closing member from its secured position and to remove it from the polygonal tube.
[0014] The end piece and the counterpart are interconnected by a threaded member that extends through the sealing element, and by tightening the threaded member the end piece and the counterpart move toward each other and bias the sealing element with axial pressure. This also provides adequate space for the compressed air channel, which ensures the necessary passage of the compressed air, and it permits in addition the threaded member to engage the counterpart in the center, which counteracts a tilting of the counterpart when the threaded member is tightened. In addition, the configuration of the end piece and counterpart in the region of the compressed air channel makes it possible to prevent the parts of the closing member from being joined in an incorrect position.
[0015] The insertion of a connecting tube into the opening of the closing member, which is formed in its end face by the compressed air channel, ensures the passage of compressed air between two polygonal tubes in a simple manner.
[0016] To insure adequate and reliable sealing effect, the length of the sealing element preferably amounts to at least 1.5 times its wall thickness. Also, the sealing element is preferably formed of rubber which provides desirable elastic properties.
[0017] The end piece of the closing member may include a recess which is sized to receive differently sized mounting screws. A supporting contour provided on both sides of the recess of the end piece counteracts a deformation of the hollow tube even in the case of an excessive torque applied to the mounting screws.
[0018] The closing member is constructed such that it seals the interior of the polygonal tube toward the recess. As a result, the mounting points of the polygonal tube section are arranged in a region of the closing member, which does not carry compressed air. The openings in the polygonal tube, through which the mounting screws of a screw connection extend between the polygonal tube and the machine, need not be sealed. The shape and the position of the recess ensure an adequate staying of the end of the polygonal tube.
[0019] The closing member of the invention seals the interior of the polygonal tube in a reliable and stable manner for a long duration. Simultaneously with the sealing effect, it is possible to secure the closing member in its position against the air pressure prevailing in the interior of the polygonal tube without additional auxiliary means. A possibly needed repair of the polygonal tube that forms the mounting rod, is easily possible and requires little labor for disassembly and assembly also when the polygonal tube is installed as a part of a mounting rod between other polygonal tubes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Further details of the invention will become apparent from the embodiment that is described in greater detail below, with reference to the Figures, in which:
[0021] FIG. 1 is a perspective view of the individual parts of a closing member which embodies the invention before its assembly;
[0022] FIG. 2 is a partially sectioned view of the parts of the closing member shown in FIG. 1 ; and
[0023] FIG. 3 is a sectional view of the end region of two polygonal tubes, each with a closing member and a connecting tube and taken along the line A-A of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] Referring more particularly to the drawings, there is illustrated a preferred embodiment of a closing member at 1 which embodies the invention. The member 1 comprises an end piece 2 , a sealing element 3 , and a counterpart 4 , which are aligned along a central axis which is shown by the dashed line in FIG. 1 . The member 1 also includes a threaded member 5 , and a sealing washer 6 , which are also positioned along the central axis.
[0025] The end piece 2 comprises a guide section 7 , whose outer contour is adapted to the inner contour of a polygonal tube 8 shown in phantom lines in FIG. 1 . The polygonal tube 8 is made square or of some other rectangular configuration. Adjacent the guide section 7 is a sealing section 9 with an outer contour of the same shape. The width and height of the outer contour of sealing section 9 are made somewhat smaller than the width and height of the guide section 7 .
[0026] At the end of the end piece 2 that faces the sealing section 9 , a stop 10 is formed, which interacts with an end face 11 of the polygonal tube 8 , and prevents the closing member 1 from being pulled or pushed into the polygonal tube 8 beyond a desired position. The guide section 7 includes a transverse recess 12 . Through this recess 12 and bore holes 13 , a mounting screw extends, which is not shown for reasons of simplification, and which is used to secure the polygonal tube to a bracket or stand. On both axially separated sides of the recess 12 , a supporting contour 14 , 15 is formed, which counteracts a deformation of the hollow polygonal tube 8 . The recess 12 in end piece 2 is dimensioned adequately large for the mounting screw, so as to be universally suited and usable for different screw sizes and screw positions that are dependent on the design of the stands. Along the central axis, the stop 10 includes an axial opening of a feed channel 16 for the threaded member 5 , and in off-center relationship, an outlet of a connecting channel 17 for carrying the compressed air.
[0027] The contoured shape of the sealing element 3 corresponds to the polygonal tube 8 and sealing section 9 , with the inner contour of the sealing element 3 being adapted to the outer contour of the sealing section 9 , and the outer contour of the sealing element 3 to the inner contour of the polygonal tube 8 . The sealing element 3 preferably consists of elastically deformable rubber. The wall thickness T of the sealing element 3 is somewhat smaller than the spacing that is present between the inner side of the polygonal tube 8 and the outer side of the guide section 7 , when the closing member 1 is inserted into the polygonal tube 8 . The length L of the sealing element 3 amounts to a multiple of the wall thickness T, and is dimensioned such that the counterpart 4 can adequately bias the sealing element 3 with axial pressure.
[0028] The counterpart 4 comprises a hollow section 18 of the same contoured shape as the sealing element 3 , and is closed at one end by a rear wall 19 as best seen in FIG. 2 . The rear wall 19 includes in inwardly directed relationship a support element 20 and a channel element 21 . With its edge 22 , the hollow section 18 projects beyond the support element 20 . The channel element 21 projects even beyond the edge 22 . The counterpart 4 can be joined in mating relationship with the end piece 2 , only when the somewhat projecting channel element 21 assumes its correct position. In the embodiment shown in FIG. 1 , the correct position of the channel element 21 is on the top left in the counterpart 4 . This ensures the necessary flow of the compressed air. Through the center of the rear wall 19 and support element 20 , a bore 23 extends, into which a screw thread is cut. Both the end piece 2 and the counterpart 4 preferably consist of a suitable metal, such as die-cast zinc.
[0029] The sectional view of FIG. 2 shows further details of the configuration of closing member 1 . In the interior of end piece 2 , the feed channel 16 changes to a smaller diameter. The transition to the smaller diameter of the feed channel 16 is shaped as a shoulder 24 . The connection channel 17 changes to a compressed air channel 25 , which has a smaller operative cross section than the connection channel 17 .
[0030] In the counterpart 4 , one can note a passageway opening 26 for the compressed air. The channel element 21 forms a part of the extension of compressed air channel 25 .
[0031] When assembling the closing member 1 , one begins with sliding the sealing element 3 onto the sealing section 9 of the end piece 2 as far as the guide section 7 . Subsequently, one inserts the threaded member 5 together with the sealing washer 6 into the feed channel 16 , with the sealing washer 6 being placed on the shoulder 24 . The end of threaded member 5 is turned into threaded bore 23 of the counterpart 4 only so far that it engages the screw thread, and that the counterpart 4 does not yet exert an axial pressure on the sealing element 3 .
[0032] The thus preassembled closing member 1 is inserted into the end of the polygonal tube 8 as far as the stop 10 . Subsequently, one tightens the threaded member 5 , whose head includes a hexagon socket 27 , so that the end piece 2 axially exerts with its edge 22 a pressure on the sealing element 3 . This causes the sealing element 3 to expand against the inner side of the polygonal tube 8 , to secure the position of the closing member 1 against the air pressure developing in the interior of the polygonal tube 8 , and to form a seal in an airtight manner between the polygonal tube 8 and the end piece 2 .
[0033] A closing member 1 in this state is shown in FIG. 3 . The compressed air is allowed to flow through the closing member 1 from the passageway opening 26 , via the compressed air channel 25 to the connection channel 17 , or in the opposite direction. Adjacent at a small distance from the polygonal tube 8 is a second polygonal tube 28 . A closing member 29 inserted into the polygonal tube 28 is made mirror-inverted with closing member 1 . The closing member 1 and closing member 29 are interconnected by a connection tube 30 , which is inserted with its ends into the connection channel 17 and connection channel 31 . With that, compressed air is allowed to flow unimpeded between the polygonal tube 8 and polygonal tube 28 through compressed air channels 25 and 33 . The connection tube 30 is sealed by means of O-ring seals 32 as disclosed in DE 198 30 048 A1.
[0034] The invention is not limited to the described embodiments. Within the scope of the invention, alternative configurations are possible, in particular of the end piece and the counterpart. | A closing member 1 for compressed air carrying polygonal tubes, which is inserted in a sealing manner into the polygonal tube at one end thereof. The closing member 1 includes an elastic sealing element 3 , and the closing member is constructed such that it biases in its inserted state the sealing element 3 in such a manner that it seals and secures the closing member 1 relative to the polygonal tube 8 . Closing members of this type are used to seal mounting tubes in yarn spinning machines with pneumatically loaded top roller support and weighting arms. | 3 |
This application is a continuation in part of Application PCT/CA2012/050407 filed Jun. 19, 2012 and claims the benefit under 35 USC 119 (e) of Provisional Application 61/499,351 filed Jun. 2, 2011.
This invention relates to an apparatus and method for embryo transfer from one female mammal to another. The description hereinafter primarily relates to mares where the commercial operation of transfer methods is desirable, but ineffective; but can relate to any female mammal.
BACKGROUND OF THE INVENTION
Embryo transfer (ET) is the process of harvesting an embryo or embryos from a donor and transferring it to a recipient. The process can be done surgically or non-surgically with the latter being the preferred method in bovine and equine species and the former being the preferred technique in smaller species such as porcine, ovine, caprine and canine.
Application for ET in the mare is commercially done for three main reasons; a donor mare in competition can produce and transfer an embryo and still compete while a recipient mare carries her genetics to a term pregnancy, to produce multiple pregnancies in one year, to transfer to a recipient mare when the donor mare is considered a high risk for pregnancy complications.
In cattle superovulation is a successful procedure where with hormone therapy multiple (average 6 but numbers as high as 40 reported) embryos can be harvested (flushed) in any one procedure. Unfortunately mares do not respond successfully to superovulation so a single procedure yields at best only one embryo. The exception is when a mare naturally double ovulates and thus two potential embryos might be retrieved. The average success of achieving a pregnancy through embryo transfer in the mare is 25%. The average cost per attempt is from $7000 to $12000 and the industry reports embryo transfer in mares to be approximately $250 000 000 annually worldwide. This means that $187 500 000 is spent with no results. This poor success has hindered the process of embryo transfer in mares from becoming a more main stream procedure.
The traditional method for transferring an embryo in mares is to aseptically pass a catheter through the vulva, vagina and cervix and into the uterine body. A cuff is inflated to seal the cervical uterine junction. The uterus is flushed with approximately 4 liters of specialized solution. The solution is filtered through a 20 micron filter. The filter is emptied into petri dishes and then the dishes are searched with microscopy to find an embryo. If found the embryo is isolated and washed in another specialized solution and then loaded into a transfer pipette. The recipient mare is aseptically prepared for transfer and the transfer pipette is passed through the vulva, vagina and cervix and into the uterine body where the embryo is deposited.
Special concern for timing is required for a successful pregnancy from an ET procedure. The procedure is considered to start at day 0 which is when the mare is observed to have ovulated. The sperm must be present in the fallopian tubes prior to ovulation. Fertilization takes place in the fallopian tubes shortly after ovulation and the embryo remains there for 5 days after which time it moves into the uterus. Flushing or retrieving the embryo is normally done at day 7 which allows for adequate time for the embryo to reach the uterus for it cannot be retrieved from the fallopian tube. After day 8 the embryo hatches from its protective shell called the zona pellucita which then makes the embryo more fragile to handle. So 7 days post ovulation achieves the highest success rates thus far. A uterus is dynamic and changes through the female cycle. For this reason a recipient mare must be synchronized with the donor mare and her uterus must be close to 7 days post ovulation which adds another level of difficulty to the procedure. At the time a flush is performed it is unknown whether there is a viable embryo present or not.
Attempts have been made to transfer embryos at later stages of development such as 11 to 14 days post ovulation. At 11 days post ovulation the embryo is visible to a highly trained practitioner using ultra-sonography. This would seem to be ideal as retrieval would only be attempted if there was a pregnancy visualized. Unfortunately no success has been achieved at this stage. It is hypothesised that the embryos were too fragile and didn't survive the procedure.
SUMMARY OF THE INVENTION
It is one object of the invention to provide an improved method and/or apparatus for use in embryo transfer.
According to one aspect of the invention there is provided a method for transfer of an embryo from a female animal comprising:
determining presence of an embryo in the uterus of a donor animal by ultra-sonic imaging;
inserting an endoscope vaginally into the uterus to a location adjacent the embryo;
operating a tool of the endoscope to extract the embryo into a container of the tool;
closing the container of the tool to enclose the embryo and extracting the endoscope to remove the embryo for transfer to a recipient animal.
Preferably the container includes two parts which move to a fully closed position.
This is preferably done by providing two hemi-spherical parts which rotate, or one of which rotates relative to the other from a first open position with one cupped inside the other to a closed spherical position sealing around the edges of the two parts. Other closure systems can be used for example a sliding sleeve arrangement around an inner tube which has a hole to collect the embryo.
Optionally there is provided a fluid supply duct for supplying fluid to the tool where the fluid supply duct opens into the closed container. In this case, there can be provided a pressure sensor for controlling pressure of the fluid inside the container to match that in the uterus. Pressure control may or may not be necessary within the closed scoop.
Preferably the container has a transverse dimension of at least 1.0 cm and preferably of the order of 1.5 cm.
Preferably the presence of the embryo is detected at a time period of the order of 11 days after insemination.
Preferably the endoscope is guided to a position within the uterus by passing through a separate guide tube inserted into the uterus through the vagina.
Preferably the guide tube is held against bending during operation of the tool so as to locate an end of the guide tube at a fixed position within the uterus. That is the guide tube is either rigid so that it cannot bend at all, or is semi-rigid so that it is adjustable in shape by bending at one or more points along its length but that it maintains that shape when in use, that is as it is inserted into the uterus through the vulva, vagina and cervix and during insertion and operation of the endoscope and tool.
It will be appreciated that the guide tube is typically inserted and guided manually by the veterinarian in many cases by feeling the position of the guide tube within the vagina of the animal by a hand inserted through the rectum. That is the end of the guide tube can be carefully guided and moved to its position within the uterus by the veterinarian feeling exactly where that end is in relation to the cervix.
The shape and arrangement of the guide tube is arranged so that the guide tube is held fixed relative to the uterus during operation of the tool so as to locate an end of the guide tube at a fixed position within the uterus. This provides a fixed point or basis for the functioning of the operating components of the endoscope for moving an end of the endoscope relative to an end of the guide tube with the end of the guide tube held in fixed position relative to the uterus. In this way the skilled veterinarian can operate the conventional operating components of bend, orientation and displacement of the end of the endoscope to accurately locate the end of the endoscope at a required position relative to the wall of the uterus.
Preferably the guide tube is held fixed relative to the uterus by locating the guide tube at the cervix.
Preferably the guide tube is located at the cervix by first and second inflating balloons with one inside the uterus at the cervix and the other outside the cervix in the vagina.
According to a second aspect of the invention there is provided a method for transfer of an embryo from a female animal comprising:
inserting an endoscope vaginally into the uterus to a location adjacent the embryo;
operating a tool of the endoscope to extract the embryo into a container of the tool;
guiding the endoscope to a position within the uterus by a guide tube inserted into the uterus through the vagina;
holding the guide tube fixed relative to the uterus during operation of the tool so as to locate an end of the guide tube at a fixed position within the uterus;
and operating components the endoscope for moving an end of the endoscope relative to an end of the guide tube.
Preferably the guide tube is held against bending during operation of the tool so as to locate an end of the guide tube at a fixed position within the uterus.
Preferably the guide tube is held fixed relative to the uterus by locating the guide tube at the cervix.
Preferably the guide tube is located at the cervix by first and second inflating balloons with one inside the uterus at the cervix and the other outside the cervix in the vagina.
Preferably the endoscope and the tool are inserted into the guide tube when the guide tube is in fixed position with the end of the guide tube within the uterus.
Based on the augmentation and refinement to the method of embryo described herein, retrieval at 9 to 13 days and more preferably 11 or 12 days can achieve success rates in excess of 80%.
In the equine uterus a cascade of events begins in which, if no embryo is present, the uterus undergoes changes and the reproductive system starts the process toward ovulation. If a viable embryo is present in the uterus it blocks the hormone and chemical pathways that initiate the cascade to ovulation thus pregnancy is maintained. At the time of transfer on day 11 or 12 the recipient's reproductive track is already undergoing changes that may make it unable to maintain a pregnancy.
In the present method, the recipient and the donor both are bred at the same time and an embryo is removed from the recipient mare and exchanged for an embryo from the donor mare. The delicate nature of the embryo is a very important consideration for success of this procedure so highly specialized equipment has been designed to overcome this.
Using this modified embryo transfer technique the procedure is cost effective and is a more attractive method of breeding in the equine industry.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:
FIG. 1 is a vertical cross sectional view through a tool for use in an endoscope for extraction of an embryo, showing the tool in an initial open position.
FIG. 2 is a cross-sectional view along the lines 2 - 2 of FIG. 1 .
FIG. 2A is a cross-sectional view along the lines 2 - 2 of FIG. 1 showing the tool in the closed position after collection of an embryo.
FIGS. 3 and 4 show the operation of the tool in a method of extraction.
FIG. 5 is a vertical cross sectional view through a second embodiment of tool for use in an endoscope for extraction of an embryo, showing the tool in an initial open position for insertion through the tube of the endoscope.
FIG. 6 is a top plan view through of the tool of FIG. 5 in the closed position after insertion through the tube of the endoscope and collection of the embryo.
FIG. 7 is a vertical cross sectional view through a tube for locating within the uterus of the animal the endoscope and tool of FIG. 1 for extraction of an embryo.
FIG. 8 is a vertical cross sectional view on an enlarged scale through the remote end of the tube of FIG. 1 showing the insertion and operation of the endoscope.
FIG. 9 is a vertical cross sectional view on an enlarged scale through the proximal end of the tube of FIG. 1 showing the control system of the endoscope.
FIG. 10 is a vertical cross sectional view on a reduced scale the tube of FIG. 1 together with the endoscope and the tool of FIG. 1 showing the components in position inserted through the vulva, vagina and cervix of the animal into the uterus.
In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
Endoscopes are a well known device widely used in surgery and other procedures and comprise a tube with a camera and illumination which can be passed through an opening into the interior of the body and which can be manipulated to different positions. A central bore allows a tool to be passed through the tube for acting on the interior, many different tools are available. Typically a collar is provided which can be inflated to locate the tube at a required portion and to seal the opening relative to the tube. Arrangements of this type are widely used and well known to persons skilled in the art so that further details are not required.
FIG. 1 shows a recovery tool for use as part of a modified endoscope 40 including a tube 10 with a camera lens 11 and an illumination source 12 carried on the tube and including fiber optic communication from a distal end 10 A of the tube 10 to control systems of the endoscope and the near end for operation by the user. The tube 10 is arranged so that it can be passed through an opening, in this case the vagina into the interior of the body. The tube includes components (not shown) which allow the end 10 A to be manipulated to different positions. One or more central bores 13 or ports allow a tool 14 to be passed through the tube. Typically a collar 15 is provided which can be inflated to locate the tube at a required portion and to seal the opening, in this case the uterus, relative to the tube.
Through one of the working ports 13 of the endoscope is inserted a grasping tool 30 . The grasping tool is small globe 20 , approximately 1.5 cm in diameter. The globe has two hemispherical halves 21 and 22 one of which rotates by sliding slides inside the other. The components are made out of surgical grade stainless steel.
When closed as shown in FIG. 2 the two parts 21 and 22 form a sealed unit or globe 20 with a sealing edge 23 . The inner part 22 is rotated around the axis of the sphere by an operating element 24 at the end of the tube 10 which is operated by a control at the near end of the tube from the open position where the inner part is wholly within the outer part to form a hemi-spherical scoop to a closed position in which the globe is closed and sealed. This globe also has a fluid port 25 within it so fluid can be added or withdrawn from the globe 20 . The fluid supply system 26 A of a control unit 26 for supply to the port 25 passes through the tube 14 and includes an inline pressure sensor 27 sensitive to the internal pressure in the line and therefore within the closed globe 20 . The supply 26 A of the control unit 26 can be operated so that holding fluid can be supplied or removed to adjust the internal pressure in the globe 20 to match the same pressure as that of a normal uterine environment for that stage of embryo. The pressure within the uterus can be measured in situ or can be predetermined from historical measurements.
The special tool described above can in some embodiments be used with a stock endoscope. The tool can alternatively be a permanent “biopsy tool” which is manufactured by assembly into place in an endoscope from a typical supplier, but where the tool is not be able to be removed after it is manufactured into the scope. This is due to the fact that the typical globe is too large for the portal through the tube of a typical endoscope.
The tool operates in a similar manner to an ice cream scoop. In the open position one half of the globe 20 is rotated inside the other half as shown in FIG. 2A . The neck 29 of the tool that passes through the endoscope portal 13 is formed from two flexible tubes 25 and 24 one inside the other. The outer tube 25 is fixed to the bottom half 21 of the globe and the inner tube 24 is fixed to the top half of the globe. At the operator end the user operates the device 26 by activating a turning movement to the inner tube 24 so that it rotates the top half of the globe to close it. The inner tube 24 also provides the fluid port which is optional.
When the tool is first inserted as shown in FIG. 4 in the open position and the collar 15 inflated to hold the tool in place, once the tool is passed into visual proximity of the embryo it can be used to pick up the embryo.
Endoscopes have the ability to pass fluid through the port 13 or through a separate special port (not shown) to dilate the inside of the tube 14 or open the lumen of the uterus.
Thus most endoscopes have a small port adjacent to the lens. This port typically has a very small metal deflector that directs water across the lens to clean it should it become obscured with mucus or other debris. The air required in the present method can also be passed through this port. There is a pump on the power unit that works the scope. At the operator end there is a two stage valve that is normally worked by the index finger. With light depression air is pumped through the port adjacent to the lens that is normally used for insufflation to allow for dilation which enhances passage of an endoscope. If the valve is fully depressed fluid is pumped through to clean the lens.
This fluid supply through the endoscope is used to open the uterus and to infuse a small amount of fluid into the uterus to float the embryo away from the tissue of the uterus wall so that it can be simply picked up with the scoop. Air or air and fluid may be used to insufflate the uterus to allow for better visualization and pull the majority of the endometrium away from the embryo. Fluid may then be used to completely free the embryo or the tool can be used to pick up the embryo at that point, if its positioning is good and endometrial contact is minimal.
Once the embryo is in view the cuff 15 will be inflated so that if further fluid is infused the embryo will not float away. When insufflation is normally done there is constant loss of air along the outside of the scope but once the embryo is in view, the cuff 15 is inflated so constant insufflation is no longer needed and dilation of the uterus can be static.
It is necessary to control the supply and volume of fluid to prevent the embryo from floating too far away. In normal instances, because the pressure in the inflation collar 15 is kept low, the natural closure/collapse of the tissue of the uterus around the collar and the tool keeps a partial seal around the instrument and provides a slope running away from the collar 15 to prevent the embryo from falling into the area of the collar 15 where it become impossible to retrieve. The injection of fluid through the endoscope typically is required because of the fragile and movable nature of the embryo. In FIG. 4 , the inflation collar 15 is close to the end of the endoscope at the location of the tool since this better locates the tube 14 and allows better control over movement of the tool. The third fluid supply tube 25 is optional but when provided acts to bathe the embryo.
When the embryo has been picked up, the tool is retracted from the donor animal and moved to the recipient. Once the embryo is placed in the recipient and the globe re-opened to release the embryo, fluid can be infused into the bottom of the globe and the embryo floated out.
The complete procedure is as follows:
1. The donor mare is synchronized in her estrous cycle with recipient mare sufficiently that they are in synchronism; or the recipient can be as much as 24 hours ahead or 72 hours but preferably not more than 48 hours behind the donor mare in her ovulation.
2. Both mares are bred on their synchronized ovulation as per normal breeding methods.
3. At earliest possible time post ovulation an embryo is searched for via ultrasonography in both the donor and recipient mares. Currently this is carried out at day 11 post ovulation when the embryo is sufficiently large to be determined by this method.
4. Once pregnancy is confirmed by the ultra-sound image in both the donor and recipient the embryo transfer and exchanged is commenced.
5. The donor and recipient mares are prepared pre-embryo recovery for a normal aseptic embryo recovery technique. Ideally the recipient mare is pregnant but that is not absolutely necessary. This transfer can still be attempted if the recipient is not pregnant but still in synchrony with the donor.
6. The procedure starts with the recipient where the recipient is sedated for ease of recovery and transfer.
7. In the recipient, a first technician operates the ultrasound imaging system to locate and document where the embryo is residing.
8. A second technician passes the recovery scope vaginally using normal aseptic palmed delivery to the cervix and the cervix is digitally enlarged and the scope is then advanced through the cervix and the operators hand is removed. The scope is then advanced until it appears on the ultrasound adjacent to the embryo. The ultrasonographer may or may not stop at this time. One the embryo is found via ultrasound the ultrasound is removed and the perineum washed thoroughly and the scope is passed into position.
9. Once the scope is in view with the embryo, the uterine horn is insufflated by air or air and fluid supply enough to free the majority of endometrial contact with the embryo. The uterus is infused with the fluid through the supply tube 25 with a fluid, such as a commercially available embryo recovery medium, to float the embryo. The inflation cuff 15 on the end of the recovery scope is arranged to prevent washing the embryo away. The embryo is captured with the grasping tool 20 on the recovery scope. The grasping tool 20 on the working end 10 A of the recovery scope 10 is now a closed and is infused with the commercially available embryo holding fluid. The recovery scope is withdrawn from the uterus. From the recipient animal, the embryo is discarded or kept for other purposes.
10. The step 9 is repeated with the donor mare.
11. The recovery scope is washed with warmed alcohol and then 1 liter of warmed saline
12. The recipient mare is sedated again if necessary and her perineum washed again.
13. The recovery scope, now containing the donor's embryo is passed using normal aseptic palmed delivery to the cervix and the cervix is digitally enlarged
14. The recovery scope is then advanced to the location from where recipients own embryo was removed. The embryo is deposited in the uterus at the bifurcation of the uterine horns. The grasping tool 20 is opened and the embryo is either dumped by turning the whole tool by the base tube 29 to invert the cup or expelled with fluid. The recovery scope is withdrawn and the procedure is complete.
The mare is checked via ultra sound immediately after the procedure for embryo placement. The mare is checked by ultrasound imaging at 6 and 24 and 48 hours post-transplant for embryo viability and procedure success.
Turning now to FIGS. 5 and 6 , a second embodiment of the tool 50 is shown which is formed of an outer sleeve 51 slideable on the outer surface of a tube 52 inside the sleeve 51 . The tube 52 has an end portion 52 A projecting beyond an end of the sleeve 51 which connects to a cylindrical stainless steel tip member 54 . The tip member is typically 2 to 3 cms long and has an elongate slot 53 in one side leading to a hollow interior 53 A. The tip member includes a portion 53 B which is necked down to a reduced diameter onto which the end portion 52 A of the tube 52 is engaged. The hollow interior 53 A of the tip member 54 communicates with the interior of the tube 52 allowing access to the interior of the tube 52 . The tube 52 and the sleeve 51 are both formed of a medical grade plastics material allowing some flexibility. The stainless steel tip member 54 has an end closure portion 54 A which closes the front end of the tip member. The metal tip member thus has a hole in the hollow interior that communicates with the slot 53 so that fluid can be passed from the inner tube 52 into the slot 53 . The outer face 54 B of the closure portion 54 A is domed or hemi-spherical to provide a smooth rounded surface of a transverse diameter or the order of 1.0 cms. The diameter of the tip member is lightly larger than that of the outer surface of the cylindrical portion of the tip member 54 to provide a shoulder 55 surrounding the end of the tube to provide an abutment for the end of the sleeve. In operation the endoscope is maneuvered to the required position and the tool 50 inserted through the bore 13 to the location of the embryo. As described previously, fluid can be supplied through the tube 52 through the opening 53 to the uterus to wash out the embryo from its position. When exposed, the embryo is scooped by rotating the tool so that the opening 53 is moved to the embryo to allow it to enter into the interior of the metal tip within the slot and not enter the tube. When the embryo is captured, the sleeve is moved longitudinally to close the hole by covering the tip portion 52 A up to the tip member 54 allowing the tool and captured embryo to be extracted. The fluid control systems previously described are used to ensure the protection of the captured embryo.
Turning now to FIGS. 7 to 10 , there is shown the tool 14 inserted through the endoscope 40 which is guided to a position within the uterus 62 by a guide tube 50 inserted into the uterus 62 through the vulva 60 , the vagina 61 and the cervix 63 .
The guide tube is rigid during insertion and during operation of the endoscope 40 and tool 14 so as to locate an end 51 of the guide tube 50 at a fixed position within the uterus 62 . Guiding to the required position is controlled by the veterinarian by holding the proximal end 52 and by feeling the location of the distal end 51 relative to the cervix through the bowel wall.
After insertion, the guide tube 50 is held fixed relative to the uterus during operation of the tool so as to locate an end of the guide tube at a fixed position within the uterus by locating the guide tube at the cervix. The guide tube is located at the cervix by first and second inflating balloons 53 , 54 on an exterior surface of the tube 50 with one 54 inside the uterus at the cervix and the other 53 outside the cervix in the vagina. Thus the cervix is located between the two balloons to prevent longitudinal movement of the tube when the balloons are inflated. Also the cervix is relatively stiff and positioned at a fixed location relative to the interior wall of the uterus so that the tube is held at a fixed location to allow the veterinarian to operate the endoscope to locate its end at a required position adjacent the wall of the uterus.
The endoscope 40 includes operating components for moving an end of the endoscope relative to an end of the guide tube with the end of the guide tube held in fixed position relative to the uterus.
The balloons 53 , 54 are defined on an outside of the body of the tube 50 by a layer of a resilient material 55 covering the body of the tube 50 which is cast in place or applied to define a passage 56 from the end 52 to the first of the balloons which then communicates with a passage 56 A to the end balloon. The balloons are formed by thinner annular sections of the covering 55 so that the annular sections inflate preferentially relative to the remainder of the covering to form annular balloons surrounding the tube body and extending over a limited extent longitudinally of the tube. The spacing between the balloons is designed to match approximately the thickness of the cervix to hold the cervix between them. In this way the balloons are inflated by an inflation pump 57 when the veterinarian has determined that the tube is at the required location to hold the tube at fixed position longitudinally and radially.
The balloons can be inflated independently by separate passages if required which can be used to locate the tube more effectively by locating it from one side of the cervix before the second balloon is inflated.
The endoscope is then inserted into the guide tube when the guide tube is in fixed position with the end of the guide tube within the uterus.
The endoscope 40 includes a conventional control system 45 operable by the veterinarian including operating components of the endoscope. These include a fluid supply 41 A for supply of a fluid to the end of the endoscope at a nozzle 41 ; a gas supply 42 A for supply of a gas to the end of the endoscope at a nozzle 42 ; a camera control 11 A for operating the camera 11 and a light control 10 A for operating eh illumination 10 . The endoscope also includes a manually operable control 43 A for operating bending elements (not shown) for bending the end of the endoscope to sides of an axis of the tube 50 . Typically this is effected by a wire pulling system which pulls on the end differentially to effect bending to one side. In addition the control system can be manually moved longitudinally as indicated at 47 A to push the end in and out of the tube 50 longitudinally as indicated at 47 . Also the control system can be manually rotated angularly around the axis of the tube 50 as indicated at 48 A to rotate the end as indicated at 48 . These controls thus allow movement of the end of the endoscope to required positions within the uterus relative to the fixed or stable end of the guide tube which is held in fixed position relative to the uterus. The tool 14 can be inserted after the required adjustment movement or can be in place while that movement is being effected.
The ultrasound system for guiding the extraction of the embryo by the veterinarian is schematically illustrated in FIG. 10 at 80 and includes a probe 81 and a display 82 . This enables the veterinarian to view the position of the embryo and to use the tool to extract the embryo as previously described. | An embryo from a female animal is transferred to another animal by determining presence of an embryo in the uterus of a donor animal by ultra-sonic imaging and inserting an endoscope vaginally into the uterus to a location adjacent the embryo. A tool of the endoscope projects to a position to extract the embryo washed into a container of the tool which is then closed by moving a closure part to enclose the embryo and extracting the endoscope to remove the embryo for transfer to a recipient animal. The fluid into the container can be controlled in pressure to maintain a required pressure generally matching that inside the uterus. | 0 |
This application claims priority to U.S. provisional application Ser. No. 61/287,956, filed Dec. 18, 2009, which along with all other references concurrently filed are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
The field of the invention is modular construction of process facilities, with particular examples given with respect to modular oil sand processing facilities.
BACKGROUND
Building large-scale processing facilities can be extraordinarily challenging in remote locations, or under adverse conditions. One particular geography that is both remote and suffers from severe adverse conditions includes the land comprising the western provinces of Canada, where several companies are now trying to establish processing plants for removing oil from oil sands.
Given the difficulties of building a facility entirely on-site, there has been considerable interest in what we shall call 2nd Generation Modular Construction. In that technology, a facility is logically segmented into truckable modules, the modules are constructed in an established industrial area, trucked or airlifted to the plant site, and then coupled together at the plant site. Several 2nd Generation Modular Construction facilities are in place in the tar sands of Alberta, Canada, and they have been proved to provide numerous advantages in terms of speed of deployment, construction work quality, reduction in safety risks, and overall project cost. There is even an example of a Modular Helium Reactor (MHR), described in a paper by Dr. Arkal Shenoy and Dr. Alexander Telengator, General Atomics, 3550 General Atomics Court, San Diego, Calif. 92121.
2nd Generation Modular facilities have also been described in the patent literatures, An example of a large capacity oil refinery composed of multiple, self-contained, interconnected, modular refining units is described in WO 03/031012 to Shumway. A generic 2nd Generation Modular facility is described in US20080127662 to Stanfield.
Unless otherwise expressly indicated herein, Shumway and all other extrinsic materials discussed herein, and in the priority specification and attachments, are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent with or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
There are very significant cost savings in using 2nd Generation Modular. It is contemplated, for example, that building of a process module costs US$4 in the field for every US$1 spent building an equivalent module in a construction facility. Nevertheless, despite the many advantages of 2nd Generation Modular, there are still problems. Possibly the most serious problems arise from the ways in which the various modules are inter-connected. In the prior art 2nd Generation Modular units, the fluid, power and control lines between modules are carried by external piperacks. This can be seen clearly in FIGS. 1 and 2 of WO 03/031012. In facilities using multiple, self-contained, substantially identical production units, it is logically simple to operate those units in parallel, and to provide in feed (inflow) and product (outflow) lines along an external piperack. But where small production units are impractical or uneconomical, the use of external piperacks is a hindrance.)
What is needed is a new modular paradigm, in which the various processes of a plant are segmented in process blocks comprising multiple modules. We refer to such designs and implementations as 3rd Generation Modular Construction.
SUMMARY OF THE INVENTION
The inventive subject matter provides apparatus, systems and methods in which the various processes of a plant are segmented in process blocks, each comprising multiple modules, wherein at least some of the modules within at least some of the blocks are fluidly and electrically coupled to at least another of the modules using direct-module to-module connections.
In preferred embodiments, a processing facility is constructed at least in part by coupling together three or more process blocks. Each of at least two of the blocks comprises at least two truckable modules, and more preferably three, four five or even more such modules. Contemplated embodiments can be rather large, and can have four, five, ten or even twenty or more process blocks, which collectively comprise up to a hundred, two hundred, or even a higher number of truckable modules. All manner of industrial processing facilities are contemplated, including nuclear, gas-fired, coal-fired, or other energy producing facilities, chemical plants, and mechanical plants.
Unless the context dictates the contrary, all ranges set forth herein should be interpreted as being inclusive of their endpoints, and open-ended ranges should be interpreted to include only commercially practical values. Similarly, all lists of values should be considered as inclusive of intermediate values unless the context indicates the contrary.
As used herein the term “process block” means a part of a processing facility that has several process systems within a distinct geographical boundary. By way of example, a facility might have process blocks for generation or electricity or steam, for distillation, scrubbing or otherwise separating one material from another, for crushing, grinding, or performing other mechanical operations, for performing chemical reactions with or without the use of catalysts, for cooling, and so forth.
As used herein the term “truckable module” means a section of a process block that includes multiple pieces of equipment, and has a transportation weight between 20,000 Kg and 200,000 Kg. The concept is that a commercially viable subset of truckable modules would be large enough to practically carry the needed equipment and support structures, but would also be suitable for transportation on commercially used roadways in a relevant geographic area, for a particular time of year. It is contemplated that a typical truckable module for the Western Canada tar sands areas would be between 30,000 Kg and 180,000 Kg, and more preferably between 40,000 Kg and 160,000 Kg. From a dimensions perspective, such modules would typically measure between 15 and 30 meters long, and at least 3 meters high and 3 meters wide, but no more than 35 meters long, 8 meters wide, and 8 meters high.
Truckable modules may be closed on all sides, and on the top and bottom, but more typically such modules would have at least one open side, and possibly all four open sides, as well as an open top. The open sides allows modules to be positioned adjacent one another at the open sides, thus creating a large open space, comprising 2, 3, 4, 5 or even more modules, through which an engineer could walk from one module to another within a process block.
A typical truckable module might well include equipment from multiples disciplines, as for example, process and staging equipment, platforms, wiring, instrumentation, and lighting.
One very significant advantage of 3rd Generation Modular Construction is that process blocks are designed to have only a relatively small number of external couplings. In preferred embodiments, for example, there are at least two process blocks that are fluidly coupled by no more than three, four or five fluid lines, excluding utility lines. It is contemplated, however, that there could be two or more process blocks that are coupled by six, seven, eight, nine, ten or more fluid lines, excluding utility lines. The same is contemplated with respect to power lines, and the same is contemplated with respect to control (i.e. wired communications) lines. In each of these cases, fluid, power, and control lines, it is contemplated that a given line coming into a process block will “fan out” to various modules within the process block. The term “fan out” is not meant in a narrow literal sense, but in a broader sense to include situations where, for example, a given fluid line splits into smaller lines that carry a fluid to different parts of the process block through orthogonal, parallel, and other line orientations.
Process blocks can be assembled in any suitable manner. It is contemplated, for example, that process blocks can be positioned end-to-end and/or side-to-side and/or above/below one another. Contemplated facilities include those arranged in a matrix of x by y blocks, in which x is at least 2 and y is at least 3. Within each process block, the modules can also be arranged in any suitable manner, although since modules are likely much longer than they are wide, preferred process blocks have 3 or 4 modules arranged in a side-by-side fashion, and abutted at one or both of their collective ends by the sides of one or more other modules. Individual process blocks can certainly have different numbers of modules, and for example a first process block could have five modules, another process block could have two modules, and a third process block could have another two modules. In other embodiments, a first process block could have at least five modules, another process block could have at least another five modules, and a third process block could have at least another five modules.
In some contemplated embodiments, 3rd Generation Modular Construction facilities are those in which the process blocks collectively include equipment configured to extract oil from oil sands. Facilities are also contemplated in which at least one of the process blocks produces power used by at least another one of the process blocks, and independently wherein at least one of the process blocks produces steam used by at least another one of the process blocks, and independently wherein at least one of the process blocks includes an at least two story cooling tower. It is also contemplated that at least one of the process blocks includes a personnel control area, which is controllably coupled to at least another one of the process blocks using fiber optics. In general, but not necessarily in all cases, the process blocks of a 3rd Generation Modular facility would collectively include at least one of a vessel, a compressor, a heat exchanger, a pump, a filter.
Although a 3rd Generation Modular facility might have one or more piperacks to inter-connect modules within a process block, it is not necessary to do so. Thus, it is contemplated that a modular building system could comprise A, B, and C modules juxtaposed in a side-to-side fashion, each of the modules having (a) a height greater than 4 meters and a width greater than 4 meters, and (b) at least one open side; and a first fluid line coupling the A and B modules; a second fluid line coupling the B and C modules; and wherein the first and second fluid lines pass do not pass through a common interconnecting piperack.
Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following description of exemplary embodiments and accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a flowchart showing some of the steps involved in 3 rd Generation Construction process.
FIG. 2 is an example of a 3rd Generation Construction process block showing a first level grid and equipment arrangement.
FIG. 3 is a simple 3rd Generation Construction “block” layout.
FIG. 4 is a schematic of three exemplary process blocks (# 1 , # 2 and # 3 ) in an oil separation facility designed for the oil sands region of western Canada.
FIG. 5 is a schematic of a process block module layout elevation view, in which modules C, B and A are on one level, most likely ground level, with a fourth module D disposed atop module C.
FIG. 6 is a schematic of an alternative embodiment of a portion of an oil separation facility in which there are again three process blocks (# 1 , # 2 and # 3 ).
FIG. 7 is a schematic of the oil treating process block # 1 of FIG. 3 , showing the three modules described above, plus two additional modules disposed in a second story.
FIG. 8 is a schematic of a 3rd Generation Modular facility having four process blocks, each of which has five modules.
DETAILED DESCRIPTION
In one aspect of preferred embodiments, the modular building system would further comprise a first command line coupling the A and B modules; a second command line coupling the B and C modules; and wherein the first and second command lines do not pass through the common piperack. In more preferred embodiments, the A, B, and C modules comprise at least, 5, at least 8, at least 12, or at least 15 modules. Preferably, at least two of the A, B and C process blocks are fluidly coupled by no more than five fluid lines, excluding utility lines. In still other preferred embodiments, a D module could be is stacked upon the C module, and a third fluid line could directly couple C and D modules.
Methods of laying out a 2nd Generation Modular facility are different in many respects from those used for laying out a 3rd Generation Modular facility. Whereas the former generally merely involves dividing up equipment for a given process among various modules, the latter preferably takes place in a five-step process as described below. It is contemplated that while traditional 2nd Generation Modular Construction can prefab about 50-60% of the work of a complex, multi-process facility, 3rd Generation Modular Construction can prefab up to about 90-95% of the work
Additional information for designing 3rd Generation Modular Construction facilities is included in the 3rd Generation Modular Execution Design Guide, which is included in this application. The Design Guide should be interpreted as exemplary of one or more preferred embodiments, and language indicating specifics (e.g. “shall be” or “must be”) should therefore be viewed merely as suggestive of one or more preferred embodiments. Where the Design Guide refers to confidential software, data or other design tools that are not included in this application, such software, data or other design tools are not deemed to be incorporated by reference. In the event there is a discrepancy between the Design Guide and this specification, the specification shall control.
FIG. 1 is a flow chart 100 showing steps in production of a 3rd Generation Construction process facility. In general there are three steps, as discussed below.
Step 101 is to identify the 3rd Generation Construction process facility configuration using process blocks. In this step the process lead typically separates the facilities into process “blocks”. This is best accomplished by developing a process block flow diagram. Each process block contains a distinct set of process systems. A process block will have one or more feed streams and one or more product streams. The process block will process the feed into different products as shown in.
Step 102 is to allocate a plot space for each 3rd Generation Construction process block. The plot space allocation requires the piping layout specialist to distribute the relevant equipment within each 3rd Generation Construction process block. At this phase of the project, only equipment estimated sizes and weights as provided by process/mechanical need be used to prepare each “block”. A 3rd Generation Construction process block equipment layout requires attention to location to assure effective integration with the piping, electrical and control distribution. In order to provide guidance to the layout specialist the following steps should be followed:
Step 102 A is to obtain necessary equipment types, sizes and weights. It is important that equipment be sized so that it can fit effectively onto a module. Any equipment that has been sized and which can not fit effectively onto the module envelop needs to be evaluated by the process lead for possible resizing for effective module installation.
Step 102 B is to establish an overall geometric area for the process block using a combination of transportable module dimensions. A first and second level should be identified using a grid layout where the grid identifies each module boundary within the process block.
Step 102 C is to allocate space for the electrical and control distribution panels on the first level. FIG. 2 is an example of a 3rd Generation Construction process block first level grid and equipment arrangement. The E&I panels are sized to include the motor control centers and distributed instrument controllers and I/O necessary to energize and control the equipment, instrumentation, lighting and electrical heat tracing within the process block. The module which contains the E&I panels is designated the 3rd Generation primary process block module. Refer to E&I installation details for 3rd Generation module designs.
Step 102 D is to group the equipment and instruments by primary systems using the process block PFDs.
Step 102 E is to lay out each grouping of equipment by system onto the process block layout assuring that equipment does not cross module boundaries. The layout should focus on keeping the pumps located on the same module grid and level as the E&I distribution panels. This will assist with keeping the electrical power home run cables together. If it is not practical, the second best layout would be to have the pumps or any other motor close to the module with the E&I distribution panels. In addition, equipment should be spaced to assure effective operability, maintainability and safe access and egress.
The use of Fluor's Optimeyes™ is an effective tool at this stage of the project to assist with process block layouts.
Step 103 is to prepare a detailed equipment layout within Process Blocks to produce an integrated 3rd Generation facility. Each process block identified from step 2 is laid out onto a plot space assuring interconnects required between blocks are minimized. The primary interconnects are identified from the Process Flow Block diagram. Traditional interconnecting piperacks are preferably no longer needed or used. Pipeways are integrated into the module. A simple, typical 3rd Generation “block” layout is illustrated in FIG. 3 .
Step 104 is to develop a 3rd Generation Module Configuration Table and power and control distribution plan, which combines process blocks for the overall facility to eliminate traditional interconnecting piperacks and reduce number of interconnects. A 3rd Generation module configuration table is developed using the above data. Templates can be used, and for example, a 3rd Generation power and control distribution plan can advantageously be prepared using the 3rd Generation power and control distribution architectural template.
Step 105 is to develop a 3rd Generation Modular Construction plan, which includes fully detailed process block modules on integrated multi-discipline basis. The final step for this phase of a project is to prepare an overall modular 3rd Generation Modular Execution plan, which can be used for setting the baseline to proceed to the next phase. It is contemplated that a 3rd Generation Modular Execution will require a different schedule than traditionally executed modular projects.
Many of the differences between the traditional 1st Generation and 2nd Generation Modular Construction and the 3rd Generation Modular Construction are set forth in Table 1 below, with references to the 3rd Generation Modular Execution Design Guide, which was filed with the parent provisional application:
TABLE 1
Traditional Truckable Modular
Activities
Execution
3 rd Gen Modular Execution
Layout &
Steps are:
Utilize structured work process to
Module
1. Develop Plot Plan using
develop plot layout based on
Definition
equipment dimensions and
development of Process Blocks with
Process Flow Diagrams
fully integrated equipment, piping,
(PFDs). Optimize
electrical and instrumentation/
interconnects between
controls, including the following
equipment.
steps:
2. Develop module boundaries
1. Identify the 3rd Generation
using Plot Plan and Module
process facility configuration
Transportation Envelop.
using process blocks using PFDs.
3. Develop detailed module
2. Allocate plot space for each 3rd
layouts and interconnects
Generation process block.
between modules and stick-
3. Detailed equipment layout within
built portions of facilities
Process Blocks using 3 rd
utilizing a network of
Generation methodology to
piperack/sleeperways and
eliminate traditional
misc. supports.
interconnecting piperack and
4. Route electrical and controls
minimize or reduce interconnects
cabling through
within Process Block modules.
interconnecting racks and misc.
The layout builds up the Process
supports to connect various
Block based on module blocks
loads and instruments with
that conform to the
satellite substation and racks.
transportation envelop.
Note: This results in a combination
4. Combine Process Blocks for
of 1 st generation (piperack) and 2 nd
overall facility to eliminate
generation (piperack with selected
traditional interconnecting
equipment) modules that fit the
piperacks and reduce number of
transportation envelop.
interconnects.
Ref.: Section 1.4 A
5. Develop a 3rd Generation
Modular Construction plan,
which includes fully detailed
process block modules on
integrated multi-discipline basis
Note: This results in an integrated
overall plot layout fully built up
from Module blocks that conform to
the transportation envelop.
Ref.: Section 2.2 thru 2.4
Piperacks/
Modularized piperacks and
Eliminates the traditional
Sleeperways
sleeperways, including cable tray
modularized piperacks and
for field installation of
sleeperways. Interconnects are
interconnects and home-run
integrated into Process Block
cables.
modules for shop installation.
Ref.: Section 2.5
Ref.: Section 2.2
Buildings
Multiple standalone pre-
Buildings are integrated into Process
engineered and stick built
Block modules.
buildings based on discrete
Ref: Section 3.3D
equipment housing.
Power
Centralized switchgear and
Decentralized MCC &
Distribution
MCC at main and satellite
switchgear integrated into
Architecture
substations.
Process Blocks located in
Individual home run feeders
Primary Process Block module.
run from satellite substations to
Feeders to loads are directly
drivers and loads via
from decentralized MCCs and
interconnecting piperacks.
switchgears located in the
Power cabling installed and
Process Block without the need
terminated at site.
for interconnecting piperack.
Power distribution cabling is
installed and terminated in
module shop for Process Block
interconnects with pre-
terminated cable connectors, or
coiled at module boundary for
site interconnection of cross
module feeders to loads within
Process Blocks using pre-
terminated cable connectors.
Ref.: Section 3.3E
Instrument
Control cabinets are either
Control cabinets are
and control
centralized in satellite
decentralized and integrated into
systems
substations or randomly
the Primary Process Block
distributed throughout process
module.
facility.
Close coupling of instruments to
Instrument locations are fallout
locate all instruments for a
of piping and mechanical
system on a single Process Block
layout.
module to maximum extent
Vast majority of instrument
practical.
cabling and termination is done
Instrumentation cabling installed
in field for multiple cross
and terminated in module shop.
module boundaries and stick-
Process Block module
built portions via cable tray or
interconnects utilize pre-installed
misc. supports installed on
cabling pre-coiled at module
interconnecting piperacks.
boundary for site connection
using pre-terminated cable
connectors.
Ref.: Section 3.3F
FIG. 4 is a schematic of three exemplary process blocks (# 1 , # 2 and # 3 ) in an oil separation facility designed for the oil sands region of western Canada. Here, process block # 1 has two modules (# 1 and # 2 ), process block # 2 has two modules (# 3 and # 4 ), and process block # 3 has only one module (# 5 ). The dotted lines between modules indicate open sides of adjacent modules, whereas the solid lines around the modules indicate walls. The arrows show fluid and electrical couplings between modules. Thus, Drawing 1 shows only two one electrical line connection and one fluid line connection between modules # 1 and # 2 . Similarly, Drawing 1 shows no electrical line connections between process blocks # 1 and 2 , and only a single fluid line connection between those process blocks.
FIG. 5 is a schematic of a process block module layout elevation view, in which modules C, B and A are on one level, most likely ground level, with a fourth module D disposed atop module C. Although only two fluid couplings are shown, the Drawing should be understood to potentially include one or more additional fluid couplings, and one or more electrical and control couplings.
FIG. 6 is a schematic of an alternative embodiment of a portion of an oil separation facility in which there are again three process blocks (# 1 , # 2 and # 3 ). But here, process block # 1 has three modules (# 1 , # 2 , and # 3 ), process block # 2 has two modules (# 1 and # 2 ), and process block # 3 has two additional modules (# 1 and # 2 ).
FIG. 7 is a schematic of the oil treating process block # 1 of FIG. 3 , showing the three modules described above, plus two additional modules disposed in a second story.
FIG. 8 is a schematic of a 3rd Generation Modular facility having four process blocks, each of which has five modules. Although dimensions are not shown, each of the modules should be interpreted as having (a) a length of at least 15 meters, (b) a height greater than 4 meters, (c) a width greater than 4 meters, and (d) having open sides and/or ends where the modules within a given process block are positioned adjacent one another. In this particular example, the first and second process blocks are fluidly coupled by no more four fluid lines, excluding utility lines, four electrical lines, and two control lines. The first and third process blocks are connected by six fluid lines, excluding utility lines, and by one electrical and one control line.
Also in FIG. 8 , a primary electrical supply from process block 1 fans out to three of the four modules of process block 3 , and a control line from process block 1 fans out to all four of the modules of process block 3 .
It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C . . . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc. | The various processes of a plant are segmented into separate process blocks that are connected to one another using fluid conduits or electrical connections. Each process block is specialized to perform specific tasks in an assembly line manner to achieve an overall goal. For example, multiple distillation process blocks could be daisy-chained to create fuel from crude oil. Each process block is generally small enough to be mounted on a truck or a flatbed for easy transport, allowing for an assembly line of process blocks to be transported anywhere in the world with ease. | 4 |
This application is a division of application Ser. No. 121,916, filed Nov. 17, 1987, now U.S. Pat. No. 4,960,701.
BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to novel N-acetylmannosamine dehydrogenase (hereinafter referred to as N-AMDH) which acts upon N-acetylmannosamine (hereinafter referred to as N-AM) to convert it into N-acetylmannosaminolactone and, at the same time, reduces nicotinamide adenine dinucleotide (NAD) into reduced nicotinamide adenine dinucleotide (NADH), as well as to a process for producing N-AMDH, an enzymatic method for quantitatively analyzing N-AM or sialic acid (hereinafter referred to as SA), and a kit for the quantitative analysis. 2. Description of the Prior Art
In the current clinical tests, SA in serum is measured, and this plays an important role in the diagnoses of acute and chronic inflammations, shocks, trauma, myocardial infarction, diabetes mellitus, liver diseases, cancers, etc.
The measurements of SA are roughly classified into chemical method and enzymatic method.
The chemical method is being gradually replaced by the enzymatic method of higher accuracy, because chemical method is inferior in various points such as specificity, workability, dangerousness of the agents used in its, etc.
Until today, method A and method B have been proposed as the enzymatic method, according to a rough classification.
Methods A and B are identical in that neuraminic acid aldolase is reacted upon SA to decompose the latter into N-AM and pyruvic acid. However, they are different from each other in that according to method A, N-AM is treated with acylglucosamine-2-epimerase and N-acetylhexosamine oxidase to form hydrogen peroxide and the latter is analyzed, while according to method B, pyruvic acid is treated with pyruvic acid oxidase or lactic acid dehydrogenase (LDH) to form hydrogen peroxide or NADH, respectively, and they are analyzed.
Method A is disadvantageous in that the existence of acylglucosamine-2-epimerase complicates the system, and method B is disadvantageous in that it is influenced by the endogenous pyruvic acid.
SUMMARY OF THE INVENTION
The present inventors studied a measurement of SA which is easy to operate and has a high accuracy. As the result, it was found that a bacterial strain belonging to Genus Flavobacterium isolated from the soil produces a novel enzyme which, when reacted with N-AM, converts the latter into N-acetylmannosaminolactone and, at the same time, reduces NAD into NADH, and this enzyme is effectively utilizable in the measurement of SA. Based on this finding, the present invention was accomplished.
Thus, the present invention provides a novel enzyme N-AMDH which, when reacted with N-AM, converts the latter into N-acetylmannosaminolactone and, at the same time, reduces NAD into NADH. Further, the invention also provides a process for producing N-AMDH which comprises culturing a strain belonging to Genus Flavobacterium and having an ability to produce N-AMDH in a medium and collecting N-AMDH from the cultured product. Further, the invention also provides a method for quantitatively analyzing N-AM which comprises treating an N-AM-containing sample with N-AMDH and determining the resulting NADH. Further, the invention also provides a method for quantitatively analyzing SA which comprises treating an SA-containing sample successively or simultaneously with N-acetylneuraminic acid aldolase and N-AMDH and determining the resulting NADH. Further, the invention also provides a quantitative analysis kit comprising at least N-AMDH, NAD and a buffer solution.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, FIG. 1 is a graph illustrating the optimum pH value of this enzyme; FIG. 2 is a graph illustrating its stable pH range; FIG. 3 is a graph illustrating the temperature range suitable for the action of this enzyme; FIG. 4 is a graph illustrating the heat stability of this enzyme; FIG. 5 is a diagram illustrating the electrophoretic band; FIG. 6 is calibration curve in Example 3; and FIG. 7 is calibration curve in Example 7; provided that the buffer solutions used in FIG. 1 and FIG. 2 were potassium phosphate buffer (-), trishydrochloric acid buffer (Δ-Δ) and glycine-sodium hydroxide buffer ( - ).
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be explained below more concretely.
Physico-chemical properties of the novel enzyme N-AMDH used in the present invention are as follows.
(1) Action and substrate-specificity
As shown in the following reaction scheme, N-AMDH oxidizes N-AM into N-acetylmannoaminolactone and, at the same time, reduces NAD into NADH in the presence of N-AM and NAD. ##STR1##
In the presence of water, N-acetylmannosaminolactone is spontaneously hydrolyzed to form N-acetylmannosaminic acid. Accordingly, the reaction is substantially irreversible. N-AMDH hardly acts or does not act at all upon other neutral sugars, hexosamine, N-acetylglucosamine and N-acetylgalactosamine, except that is acts upon N-glycolylmannosamine in the same manner as above. It hardly utilizes nicotinamide adenine dinucleotide phosphate (NADP), 2,6-dichlorophenol indophenol and the like as electron acceptor.
(2) Optimum pH and stable pH range
Its optimum pH is 8.0 to 9.0, when trishydrochloric acid buffer is used.
FIG. 1 illustrates the results of enzymatic activity measurement using potassium phosphate buffer, tris-hydrochloric acid buffer and glucine-sodium hydroxide buffer.
As shown in FIG. 2, its stable pH range is 8.5 to 9.5.
The buffer solutions used there are potassium phosphate buffer, tris-hydrochloric acid buffer and glycine-sodium hydroxide buffer.
(3) Temperature range suitable for its action As shown in FIG. 3, it is 35° C. to 50° C.
(4) Conditions (pH, temperature) of inactivation
As shown in FIG. 4, it keeps activity at stable up to a temperature of 45° C., when heat treated for minutes. At temperatures exceeding 45° C., it rapidly loses its activity. When heat treated at 45° C. for 10 minutes, it is stable at a pH of 8.5-9.5, while it is particularly instable at a pH value of 7 or below.
(5) Influence of inhibitor and stabilization
______________________________________Inhibitor Residual activity (%)______________________________________None 100HgCl.sub.2 6NiSO.sub.4 69ZnSO.sub.4 71CuSO.sub.4 79NaN.sub.3 83SDS 18KCN 101EDTA 89BSA 96PCMB 95Iodoacetamide 878-Hydroxyquinoline 95o-Phenanthroline 87α,α'-Dipyridyl 975'-AMP 76______________________________________
The table presented above illustrates the enzymatic activity of N-AMDH measured in solutions containing various metallic ions and inhibitors at a concentration of 2 mM. There is known no substance making a particular contribution to its activation and stabilization.
(6) Method of purification
This enzyme can be isolated and purified according to usual purifying means such as column chromatography using DEAE-cellulose, precipitation using ammonium sulfate, column chromatography using DEAE-Sephadex, column chromatography using 5'-AMP-Sepharose, gel filtration using Sephadex, and the like, or combinations thereof.
(7) Molecular weight
As measured by gel filtration method using 0.05M tris-hydrochloric acid buffer (containing 0.1M NaCl) and Sephadex G-200 column, its molecular weight is about 110,000 to 120,000.
(8) Electrophoresis using polyacrylamide gel
As shown in FIG. 5, acrylamide disk electrophoresis using 7.5% polyacrylamide gel gives a nearly single band. The migration distance after 80 minutes at 4 mA is 28 mm.
(9) Isoelectric point
As measured by acrylamide gel isoelectric focusing, its isoelectric point is 4.9.
(10) Activity measurement
To 1.8 ml of 0.05M tris-hydrochloric acid buffer (pH 8.2) is added 0.1 ml of 60 mM NAD solution. After keeping the mixture at 37° C. for 10 minutes, 10 microliters of enzyme solution is added, and then 0.1 ml of 0.3M N-AM is added. By homogenizing the mixture, the reaction is started. The reaction mixture is immediately transferred into a light absorbance measurement cell (light path 1 cm) kept at 37° C., and absorbance is measured over a period of 5 minutes (if necessary, over a longer period of time) at intervals of one minute at a wavelength of 340 nm. A quantity of enzyme capable of forming 1 micromole of NADH in one minute is taken as one unit.
As above, the enzyme of this invention is a novel enzyme which is entirely hitherto unknown in action and substrate-specificity.
Next, the production process of the novel N-AMDH according to the present invention will be explained.
The microbial strain used belongs to Genus Flavobacterium and has an N-AMDH-producing ability. One concrete example of such strain is Flavobacterium sp. No. 141-8; and varieties and mutant strains thereof are also usable. Flavobacterium sp. No. 141-8 is a strain which has been isolated by the present inventors firstly from the soil, and its bacteriological properties are as follows.
(a) Morphology
Microscopic observation (cultured in sugar-bouillon medium at 30° C. for 16 hours)
(1) Size of cell: Rod having a size of 0.45-0.5×0.5-11 microns.
(2) Polymorphism of the cell: The shape ranges from a nearly spherical form to longer rod-like form, with contamination by short chain-like conjunction at terminals.
(3) Motility: Non-motile.
(4) Spore: None.
(5) Gram-stain: Negative.
(6) Acid-fast: Negative.
(b) State of Growth in Various Media
(1) Bouillon-agar plate culture (2 days at 30° C.)
Circular colonies are smooth and translucent; 0.5 mm diameter; relatively bad growth.
(2) Sugar-bouillon-agar plate culture (2 days at 30° C.)
Circular colonies are smooth and translucent; 0.8 mm in diameter; milky white mucous colonies are formed in 5 days; no pigment produced.
(3) Sugar-bouillon-agar slant culture (2 days at 30° C.)
Milky turbid mucous liquid; in 3 days, the liquid flows down and gathers at bottom.
(4) Sugar-bouillon liquid culture (2 days at 30° C.)
A slight growth
(5) Bouillon-gelatin stab culture (3 days at 30° C.)
A slight growth without liquefaction.
(6) Litmus milk: No change, nor coagulation.
(c) Physiological Properties
(1) Reduction of nitrates: Positive.
(2) Denitrification: Negative.
(3) MR test: Negative, provided that positive in aerobic culture.
(4) VP test: Negative.
(5) Formation of indole: Negative.
(6) Formation of hydrogen sulfide: Negative.
(7) Hydrolysis of starch: Negative.
(8) Utilization of citric acid: Negative.
(9) Utilization of inorganic nitrogen source: Ammonia is utilized, while nitric acid is not utilized.
(10) Formation of pigment: Negative.
(11) Urease: Positive.
(12) Oxidase: Positive.
(13) Catalase: Positive.
(14) Growing condition range: 15° C.-41° C. (optimum temperature 30° C.), pH 4.5-8.5 (optimum pH ca. 6.5)
(15) Behavior to oxygen: aerobic; a slight growth under anaerobic condition, too.
(16) O-F test: No change, or a very weak fermentation.
(17) Formation of acid and gas from sugars: * means aerobic culture:
______________________________________ *Formation of acid Formation of gas______________________________________(i) L-Arabinose + -(ii) D-Xylose + -(iii)D-Glucose + -(iv) D-Mannose + -(v) D-Fructose + -(vi) D-Galactose + -(vii)Maltose + -(viii)Sucrose + -(ix) Lactose + -(x) Trehalose + -(xi) D-Sorbit + -(xii)D-Mannit + -(xiii)Inosit + -(xiv)Glycerin + -(xv) Starch - -______________________________________
(d) Other Characteristics
(1) Penicillin resistance: Growth even at 100 units/ml.
(2) Sodium chloride resistance: No growth above 2%.
(3) Motility of colony rim: No fluidity observed.
(4) Decomposition of Tween 80: Negative.
(5) Decomposition of esculin: Negative.
By comparing the above-mentioned characteristic properties of the above-mentioned novel N-AMDH-producing strain with the classification mentioned in "Bergey's Mannual of Systematic Bacteriology (1984) Vol. 1", it is considered that this strain belongs to Genus Flavobacterium because it is a gram-negative, aerobic, non-sporeforming bacillus having no motility, and it is catalase-positive and oxidase-positive and forms acid from many sugars under aerobic conditions, and it is resistant to Penicillin.
Since it forms acid from sugars under aerobic conditions, it is considered analogous to Flavobacterium spiritivorum. However, it is different from the latter in the decomposition of esculin, reduction of nitrate and decomposition of Tween 80. Thus, it can be regarded as a novel strain unknown so far.
For the reasons mentioned above, this strain has been named Flavobacterium sp. No. 141-8. Flavobacterium sp. No. 141-8 has been deposited in Fermentation Research Institute, Agency of Industrial Science and Technology, Ministry of International Trade and Industry, Japan, as FERM BP-1222 under the Budapest Treaty on the International Recognition of the Deposit of Microorganisms for the Purpose of Patent Procedure.
The medium used in the present invention may be any of synthetic and natural media, so far as it appropriately contains carbon source, nitrogen source, inorganics and other nutrients. As the carbon source, glucose, galactose, fructose, xylose, glycerin and the like can be used. As the nitrogen source, not only ammonium salts but also nitrogen-containing organic compounds such as peptone, digested casein, sodium glutaminate, yeast extract and the like are successfully usable. As the inorganics, salts of sodium, potassium, magnesium, manganese, calcium, iron and the like can be used.
In the present invention, N-AMDH is obtained in a high yield when a strain having N-AMDH-producing ability is cultured or dipped in a medium containing N-AM or N-acetylglucosamine. As a preferable example of said medium, a medium comprising 0.5% of N-AM, 0.1% of meat extract, 0.5% of polypeptone, 0.2% of yeast extract, 0.14% of sodium chloride and 0.1% of monopotassium hydrogen phosphate and having a pH value of 6.8 can be referred to. When the strain is subjected to aeration-agitation culture in this medium at 30° C. for 36 hours, the production titer is 10 to 100 times as high as that obtained in a culture using other carbon source in place of N-AM.
Temperature of the culture is usually 20° to 40° C. and preferably 30° to 33° C. Starting pH of the culture is usually 6 to 8 and preferably about 7. Under such conditions, a shaking culture or a submerged agitation culture is carried out for 20 to 40 hours. Otherwise, the bacterial cells which have been grown in other medium suitable for its growth and not containing A-AM or N-acetylglucosamine are dispersed in the above-mentioned medium at a high concentration aerobically for 1-10 hours in the presence of N-AM and N-acetylglucosamine. Thus, N-AMDH is accumulated in the cultured product or cell suspension.
Since N-AMDH is usually present in bacterial cells, it is preferable to separate bacterial cells by centrifugation or filtration. By destructing the cells in an appropriate amount of buffer, the enzyme is solubilized and released into the solution.
As the means for destructing bacterial cells, physical means such as Dynomill, French press, ultrasonic wave and the like, chemical means such as Triton X-100, sodium lauryl sulfate, EDTA and the like, or enzymatic means such as lysozyme and the like is used either alone or in combination. After destructing bacterial cells, nucleic acid is removed in the usual manner and insoluble matter is removed by filtration or centrifugation, whereby N-AMDH is obtained.
If desired, N-AMDH thus obtained is further purified according to the conventional means for isolation and purification of enzymes such as (1) column chromatography using DEAE-cellulose column, (2) fractionating precipitation using ammonium sulfate, (3) column chromatography using DEAE-Sephadex column, (4) column chromatography using 5'-AMP-Sepharose column, (5) gel filtration using Sephadex, and the like, or their appropriate combination, whereby a purified N-AMDH can be obtained.
Next, the method for quantitatively analyzing N-AM or SA and the quantative analysis kit of the present invention will be concretely illustrated.
The principle of the measurement of the invention is as shown below: ##STR2##
That is, N-AMDH is reacted with N-AM in a sample, and the formed NADH is measured according to well known method of measurement, such as measurement of absorbance at 340 nm (ultraviolet region).
Otherwise, it is also possible to measure the formed NADH by contacting sample with various enzymes fixed on a solid. If necessary for preventing the influence of coexisting LDH, an inhibitor such as oxamic acid, oxalic acid or the like may be added in an appropriate amount.
The N-AMDH used in the invention may be of any origin. Preferably, the N-AMDH obtained by culturing a microorganism, particularly a strain selected from the bacteria belonging to Genus Flavobacterium, is used.
As the above-mentioned enzyme-producing strain belonging to Genus Flavobacterium, Flavobacterium sp. No. 141-8 (FERM BP-1222) can be referred to, for example.
In reacting N-AMDH with N-AM in a sample, the reaction is carried out at a pH value of 7-10 at a temperature of 50° C. or below, preferably at a pH value of 8-9.5 at a temperature of 30°-45° C., and usually for a period of about 2 to 20 minutes. For regulating pH value, any buffer solution may be used, so far as it can maintain the above-mentioned pH range and does not disturb the enzymatic reaction. For example, potassium phosphate buffer, tris-hydrochloric acid buffer, glycine-sodium hydroxide buffer, sodium carbonate buffer and the like are successfully usable for this purpose.
Though the quantitative analysis of NADH formed by the action of N-AMDH may be carried out by any methods, the most generally used method is measurement of absorbance at 340 nm (ultraviolet region). Apart from above, there are a few methods which comprise converting NADH into a dye having absorption in the visible region and then determining the dye, such as the method which comprises reacting NADH with phenazine methosulfate and Nitrobluetetrazolium and measuring the absorption of the resulting diformazan at 570 nm, and the method which comprises reacting NADH with NADH-oxidase (J. Biochem. 98, 1433 (1985)), phenazine methosulfate or an electron transferring substance or metallic ion exhibiting a similar behavior to form hydrogen peroxide, developing a color therefrom in the presence of peroxidase and various chromogens, and measuring absorbance at appropriate wavelengths. When NADH is derived into hydrogen peroxide, it is also possible to analyze it by developing a luminescence from it in the presence of luminol. It is also possible to analyze NADH semi-quantitatively by adding appropriately selected plural redox indicators and electron transferring substances and observing the color tone. All these method of detection may be selected in accordance with their characteristic features.
In quantitatively analyzing SA, an SA-containing sample is reacted with N-acetylneuraminic acid aldolase to decompose SA into N-AM and pyruvic acid, followed by treating the decomposant solution with N-AMDH and making measurement in the same manner as above.
In analyzing SA, the SA in a sample must be in the liberated state. When SA is combined with protein or glycolipid as in serum, plasma and some tissues, the SA is once liberated by the action of neuraminidase and then analyzed. Though the neuraminidase used in this case may be of any origin, those produced by microorganisms belonging to Genus Clostridium, Genus Arthrobacter, Genus Corynebacterium, Genus Streptococcus, etc. are preferable.
Next, the kit of the invention for quantative analysis of N-AM or SA is composed of N-AMDH or N-AMDH and N-acetylneuraminic acid aldolase, NAD, enzymes and reagents for quantatively analyzing the formed NADH, and buffering reagent for smoothly advancing the reaction. These reagents and enzymes are used in the form of liquid, solid or freeze-dried material, and they are dissolved and mixed into buffer solution before use in accordance with requirement to make a measuring reagent.
In determining N-AM, the kit is directly acted upon N-AM-containing sample to form NADH. The NADH is measured either directly or after addition of NADH-analyzing reagents.
In determining SA, N-acetylneuraminic acid aldolase is firstly reacted upon sample to form N-AM. Next, N-AMDH is reacted to form NADH. The NADH is determined either directly or after addition of NADH-measuring reagents. The system for the measurement may be any of single reagent system, double reagent system and multi reagent system.
When the novel N-AMDH of the present invention is used, N-AM can be quantitatively analyzed with a high accuracy and based on it the quantity of SA can be known. As its result, various diseases can be diagnosed effectively. Further, according to the invention, N-AM can be exactly analyzed quantitatively without influence of coexisting N-acetylhexosamine, which is quite meaningful in the studies of complex sugars. Similarly, the present invention enables to quantitatively analyze SA with a high exactness without influence of endogenous pyruvic acid, which is quite meaningful in the diagnosis based on clinical tests of SA.
Next, the present invention will be illustrated with reference to the Examples.
EXAMPLE 1
300 ml Erlenmeyer flask containing 50 ml of a seed culture medium (pH 8.0) containing 0.75% of glucose, 0.2% of yeast extract, 0.5% of polypeptone, 0.1% of meat extract, 0.14% of sodium chloride and 0.1% of monopotassium hydrogen phosphate was inoculated with Flavobacterium sp. No. 141-8 (FERM BP-1222). After a shaking culture at 30° C. for 24 hours, the seed culture fluid was transplanted into a jar fermenter (manufactured by Iwashiya Seibutsu Kagaku K. K.) containing 2 liters of the same medium as above and subjected to an aeration (2 liters/minute) agitation (400 rpm) culture at 30° C. for 36 hours. The culture fluid was centrifuged at 8,000 rpm for 20 minutes to collect the bacterial cells.
The cells were transferred into the same jar fermenter as above containing 2 liters of a medium containing 0.2% of N-AM, 0.1% of meat extract, 0.5% of polypeptone, 0.2% of yeast extract, 0.14% of sodium chloride and 0.1% of monopotassium hydrogen phosphate and having a pH value of 6.8, and culture was continued under the same conditions as above. Six hours after, activity of N-AMDH reached the maximum.
To 1.7 kg of alive bacterial cell obtained, 10 liters of 0.02M tris-hydrochloric acid buffer (pH 8.0, hereinafter this is referred to as "standard buffer") was added, and then Triton X-100 and EDTA were added so that their concentration came to 0.5% and 2 mM, respectively. The mixture was stirred overnight in a cold room to obtain a uniform suspension. It was milled by means of Dynomill (manufactured by SHINMARU Enterprise Co., Sweden) at 3,000 rpm and centrifuged at 8,000 rpm for 20 minutes to obtain 7.3 liters of a supernatant liquid.
Then, 1.4 kg of DEAE-cellulose in wetness was added to the supernatant liquid, and the mixture was adjusted to pH 8.0 and stirred for 30 minutes to have the enzyme adsorbed on the DEAE-cellulose. After transferring it to Buchner's funnel and filtering it, it was washed with 4 liters of standard buffer and then with 5 liters of standard buffer containing 0.3M of sodium chloride. The fractions eluted with the last washing were combined and concentrated to one liter by means of hollow fiber ultrafiltrater (manufactured by Asahi Kasei Kogyo K. K.).
Into the concentrate was added and dissolved 125 g of ammonium sulfate. After thoroughly stirring the mixture and allowing it to stand for 2 hours, it was centrifuged at 9,000 rpm for 20 minutes to obtain 850 ml of supernatant liquid. After adding an additional 166 g of ammonium sulfate and thoroughly dissolving it, the mixture was left standing overnight in a cold room.
Then it was centrifuged at 12,000 rpm for 20 minutes to collect the resulting precipitate, and the latter was dissolved into 850 ml of standard buffer. After dissolving 35 g of ammonium sulfate thereinto, the resulting solution was passed through a column (5 cm in diameter and 34 cm in height) of Phenyl-Sepharose CL-4B (manufactured by Pharmacia Fine Chemicals, Sweden) previously equilibrated with standard buffer containing 4% of ammonium sulfate to have the enzyme adsorbed on the column. The enzyme was eluted with 10 liters of standard buffer having a concentration gradient of ethylene glycol (0 to 30%) and a reverse concentration gradient of ammonium sulfate (4 to 0%) at the same time.
The eluate was concentrated by ultrafiltration and dialyzed against standard buffer containing 0.1M sodium chloride. Then it was passed through a DEAE-Sephadex A-50 column (5 cm in diameter and 52 cm in height) previously equilibrated with standard buffer containing 0.1M sodium chloride for the sake of adsorption, and then the adsorbed matter was eluted with 10 liters of standard buffer having a sodium chloride concentration gradient ranging from 0.1M to 0.28M.
The active fraction was concentrated by ultrafiltration and then dialyzed against 0.01M potassium phosphate buffer (pH 6.5). Then it was passed through a column (4 cm in diameter and 16 cm in height) of 5'-AMP-Sepharose CL-4B (manufactured by Pharmacia Fine Chemicals, Sweden) previously equilibrated with 0.01M potassium phosphate buffer (pH 6.0) for the sake of adsorption, and the adsorbed matter was eluted with a buffer having sodium chloride concentration gradient (0-0.5M) and pH gradient (6.0-8.0) at the same time, by the use of 4 liters of 0.01M phosphate buffer (pH 6.0) and 4 liters of 0.01M phosphate buffer containing 0.5M sodium chloride (pH 8.0).
The active fraction was adjusted to pH 8.0 and then concentrated to 1 ml by means of ultra filter and collodion bag concentration apparatus, and the concentrate was dialyzed against standard buffer containing 0.1M sodium chloride. The dialyzed solution was subjected to gel filtration through a Sephadex G-200 column (2.5 cm in diameter and 95 cm in height) previously equilibrated with standard buffer containing 0.1M sodium chloride.
The active fractions were combined and concentrated to obtain 2200 units of purified N-AMDH. As shown in FIG. 5, it was an enzyme sample exhibiting a nearly single band in disk electrophoresis.
EXAMPLE 2
In the same manner as in Example 1, Flavobacterium sp. No. 141-8 was transplanted into 50 ml of a seed culture medium (pH 6.8) containing 0.5% of N-AM, 0.8% of polypeptone, 0.1% of meat extract, 0.2% of yeast extract and monopotassium hydrogen phosphate and subjected to a shaking culture at 30° C. for 24 hours.
The culture fluid was transplanted into a miniature jar fermenter containing the same medium as above, and subjected to aeration (2 liters/minute) agitation (400 rpm) culture at 30° C. for 40 hours. N-AMDH was accumulated in the bacterial cells. The bacterial cells thus obtained were treated in the same manner as in Example 1 to obtain an N-AMDH sample.
EXAMPLE 3
Concentration of N-AM in the solution was determined with the following reagents.
______________________________________1. Reagents0.1M phosphate buffer (pH 8.0) 880 microlitersNAD (60 mM) 50 microlitersN-AMDH (123 units/ml) 30 microlitersSample solution 20 microliters2. Method of determination______________________________________
Predetermined quantities of the reagents were taken into a test tube and reacted at 37° C. for 10 minutes, after which absorbance was measured at 340 nm. In a blank test, the above-mentioned procedure was repeated, except that the sample solution was replaced with an identical quantity of water. Absorbance of the blank run was subtracted from that of the sample run, and the remainder was taken as absorbance of sample solution. Apart from above, N-AM solutions having known concentrations were treated in the same manner as above, from which a calibration curve was prepared. From the calibration curve, a concentration of N-AM in unknown sample was determined. FIG. 6 is the calibration curve.
EXAMPLE 4
Concentration of N-AM in solution was determined by the following method by the use of the following reagents.
______________________________________1. Reagents0.1M Phosphate buffer (pH 8.0) 140 microliters(containing 0.1% Triton X-100)Phenazine methosulfate (1 mg/ml) 5 microlitersNitroblue tetrazolium (10 mg/ml) 5 microlitersNAD (40 mg/ml) 20 microlitersN-AMDH (123 units/ml) 10 microlitersSample solution 10 microliters2. Method of determination______________________________________
Predetermined quantities of the above-mentioned reagents were taken into a test tube and reacted at 37° C. for 15 minutes. Then, 2.0 ml of 0.3N hydrochloric acid was added and thoroughly stirred. Absorbance of the formed color was measured at 570 nm. In a blank test, the reaction was repeated, except that the sample solution was replaced with identical quantity of water. Absorbance of blank solution was subtracted from that of the sample solution, and the remainder was taken as absorbance of sample. Apart from above, a calibration curve was prepared from solutions having known N-AM concentrations. From the calibration curve, N-AM concentration in sample solution was determined.
EXAMPLE 5
Quantity of SA in serum was determined by the following procedure with the following reagents.
______________________________________1. ReagentsA. 10mM Phosphate buffer (pH 6.6) 1 ml Neuraminidase (5 units/ml) 1 ml N-Acetylneuraminic acid aldolase 1 ml (10 units/ml)B. 0.1M Phosphate buffer (pH 8.0) 5.7 ml N-AMDH (123 units/ml) 0.6 ml NAD (60 mM) 0.5 ml Oxamic acid 4.4 mg2. Method of determination______________________________________
Twenty microliters of serum was taken into a test tube, to which was added 300 microliters of reagent A. After reacting them at 37° C. for 15 minutes, 680 microliters of reagent B was added and reacted for an additional 10 minutes. Absorbance of the reaction mixture was measured at 340 nm. In blank test, the above-mentioned procedure was repeated except that reagent A was replaced with water. Absorbance of blank run was subtracted from that of the sample run. A calibration curve was prepared from solutions containing known concentrations of N-acetylneuraminyllactose. From the calibration curve, SA concentration in sample was determined.
EXAMPLE 6
Activity of N-acylglucosamine-2-epimerase extracted from hog kidney was determined by the following procedure with the following reagents.
______________________________________1. ReagentsA. 0.5M Tris-hydrochloric acid buffer 25 microliters (pH 7.4) 0.1M MgCl.sub.2 25 microliters 0.1M Acetylglucosamine 100 microliters 0.1M ATP (adjusted to pH 7.6) 10 microlitersB. 0.1M Tris-hydrochloric acid buffer 700 microliters (pH 8.2) N-AMDH (123 units/ml) 30 microliters NAD (60 mM) 100 microliters2. Method of Determination______________________________________
An enzyme solution extracted from hog kidney (Biochemistry, 9, 3363) was dissolved into 20 mM potassium phosphate buffer (pH 7.6), and 10 microliters of the resulting solution was reacted with reagent A at 37° C. for 20 minutes. It was heated at 100° C. for 2 minutes and then cooled to 37° C., after which a predetermined amount of reagent B was added and reacted for 5 minutes. Absorbance of the reaction mixture was measured at 340 nm. In blank test, the above-mentioned procedure was repeated, except that the enzyme solution was replaced with water. Absorbance of the blank run was subtracted as control from that of sample run, and the remainder was taken as the increase of absorbance attributable to the formed N-AM. Based on the fact that 1 mM of N-AM corresponded to an absorbance of 6.27 in the reaction mixture, concentration of N-AM was calculated, and it was taken as the amount of N-AM formed during 20 minutes. By converting it into "formation per one hour" and multiplying the latter by 100, enzyme activity per 1 ml of enzyme solution was determined.
EXAMPLE 7
Concentration of SA in a solution was determined by the following procedure with the following reagents.
______________________________________1. Reagents0.1M Phosphate buffer (pH 8.0) 610 microlitersN-Acetylneuraminic acid aldolase(manufactured by Nakarai KagakuK. K.) (10 units/ml) 300 microlitersNAD (60 mM) 53 microlitersN-AMDH (123 units/ml) 60 microlitersSample solution 20 microliters2. Method of determination______________________________________
Predetermined quantities of the reagents were taken into a test tube and reacted at 37° C. for 10 minutes, after which absorbance of the reaction mixture was measured at 340 nm. In blank test, the above-mentioned procedure was repeated, except that N-acetylneuraminic acid aldolase was replaced with identical quantity of water. Absorbance of the blank run was subtracted from that of sample run, and the remainder was taken as an absorbance of sample solution. Apart from the above, a calibration curve was prepared by treating SA solutions of known concentrations in the same manner as above. From the calibration curve, SA concentration in sample solution was determined. FIG. 7 is the calibration curve.
EXAMPLE 8
Concentration of SA in solution was determined by the following procedure with the following reagents.
______________________________________1. Reagents0.1M Phosphate buffer (pH 8.0) 100 microliters(containing 0.1% Triton X-100)Phenazine methosulfate (1 mg/ml) 5 microlitersNitroblue-tetrazolium (10 mg/ml) 5 microlitersNAD (40 mg/ml) 20 microlitersN-Acetylneuraminic acid aldolase 40 microliters(manufactured by Nakarai KagakuK.K.) (10 units/ml)N-AMDH (123 units/ml) 10 microlitersSample solution 10 microliters2. Method of determination______________________________________
Predetermined quantities of the above-mentioned reagents were taken into a test tube and reacted at 37° C. for 15 minutes. After adding 2.0 ml of 0.3N hydrochloric acid, it was thoroughly stirred. Absorbance of the formed color was measured at 570 nm. In blank test, the above-mentioned treatment was repeated, except that N-acetylneuraminic acid aldolase was replaced with identical quantity of water. Absorbance of the blank run was subtracted as control from that of the sample run, and the remainder was taken as an absorbance of sample. Apart from above, a calibration curve was prepared by treating SA solutions of known concentrations in the same manner as above. From the calibration curve, SA concentration in sample solution was determined. | N-Acetylmannosamine dehydrogenase which takes off hydrogen from N-acetylmannosamine to convert it into N-acetylmannosaminolactone and, at the same time, reduces coenzyme NAD into NADH. This enzyme can be obtained by culturing, in a medium, a strain belonging to Genus Flavobacterium and having an ability to produce N-acetylmannosamine dehydrogenase producing activity, and then collecting it. This enzyme is usable in the quantitative analysis of N-acetylmannosamine or sialic acid. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a divisional patent application of previously copending U.S. Ser. No. 583,130, filed on Feb. 24, 1984, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a bed for baby carriages and particularly it relates to a bed for baby carriages which is collapsible, wherein a portion for supporting a baby is basically in the form of a bed capable of taking the form of a chair when desired.
2. Description of the Prior Art
Originally or at least when the baby carriage was first proposed, it was of the so-called "box-type" in which a baby is comfortably laid in the baby carriage. For babies, therefore, the box type is preferable from the standpoint of their growth and is superior in baby carriage livableness or comfortableness. However, the change of times has gradually taken the edge off such baby-centered construction concept and placed more importance on the convenience of baby carriages as a means for conveying babies. For example, the chair type has predominated in baby carriages and, further, because of the use of means of transportation, collapsible small-sized baby carriages are most popular. This is an inevitable consequence of various changes in life style and is one of the needs of the times.
The convenience of baby carriages as a means for conveying babies, as described above, is an important consideration in developing a new baby carriage. However, it seems necessary to go back to the starting point to think over what construction a baby carriage should have which does not hamper a baby's growth and does not reduce the comfortableness of a baby carriage and which is convenient to use.
SUMMARY OF THE INVENTION
An object of this invention is to provide a bed for a baby's carriages which does not hamper baby growth or degrade the comfort provided by a baby carriage, as described above. According to this invention, the bed is adapted to change its shape into chair form.
This invention provides a bed for baby carriages which is of the so-called "box-type" and is basically in the form of a box as a whole comprising a bottom wall, a front wall, a back wall, and right-hand and left-hand side walls. In such box-shaped bed, when the walls disposed in the front are displaced to another place and when particularly in the bottom wall its rear portion alone is left to form the seat of a chair, the bed takes the form of a chair. For this purpose the present construction comprises a pair of draw links longitudinally slidably installed on opposite sides under the bottom wall, so that said draw links, when forwardly withdrawn, hold the front portions of the bottom wall and left-hand and right-hand side walls, and the front wall. The front portions of the left-hand and right-hand side walls are constructed to be separable from their rear portions. Further, the front portion of the bottom wall is constructed to be displaceable as by sliding or turning relative to its rear portion. When the draw links are rearwardly retracted, the front portions of the bottom wall and left-hand and right-hand side walls and the front wall are displaced to open the front of the baby carriage bed, enabling the bed to be used as a chair.
According to this invention, there is provided a bed for baby carriages which is in the form of a box which is desirable from the standpoint of a baby's growth and comfort. The change of such basic bed form into the chair form does not require any addition of separately prepared new members or removal of any of the members initially provided as part of the bed. It is only necessary to deform or displace some of the members provided in the bed while they are associated with the others. That is, when the pair of draw links are slid and thereby forwardly withdrawn, they assume the state of holding the members forming the front portion of the bed, while when they are rearwardly, retracted, the front portion of the bottom wall is displaced from the predetermined position and other walls are deformed, whereby the front of the bed is opened to enable the bed to be used as a chair. Therefore, there is no danger whatsoever of losing parts which is liable to occur where separable members are provided.
These objects and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a right-hand side view of a baby carriage embodiment of this invention with a bed shown in its original bed form;
FIG. 2 is a perspective view showing the bed portion of FIG. 1;
FIG. 3 shows a state in which the bed of FIG. 2 is changed into a chair form;
FIG. 4 is a perspective view showing the draw links of FIG. 1 and the related arrangement;
FIG. 5 is a right-hand side view of a baby carriage showing another embodiment of this invention, with the bed shown in its original bed form;
FIG. 6 is a perspective view of the bed of FIG. 5, showing an intermediate state of the change into a chair form;
FIG. 7 is an enlarged perspective view showing a draw link of FIGS. 5 and 6 and the related arrangement;
FIG. 8 is a front view, partly in section, showing the relation between the draw link and a tubular member of FIG. 7;
FIG. 9 shows the bed of the baby carriage of FIG. 5 changed into a chair form;
FIG. 10 is a perspective view of a modified bed form;
FIG. 11 is a perspective view of the bed of FIG. 10 changed into chair form; and
FIG. 12 is a sectional view taken along the line XII--XII in FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1, 2, and 3, the baby carriage bed 1 is in the form of a box comprising a bottom wall 2, a front wall 3, a back wall 4, and left-hand and right-hand side walls 5 and 6. These walls are formed of suitable fabric or the like, and in some portions the flexibility of the fabric or the like is utilized and in other portions hard cores are incorporated to provide a suitable degree of strength or "stiffness."
In FIG. 1, the bed 1 is shown with its right-hand side wall 6 removed. The bottom wall 2 has hard cores incorporated therein which are separated as front and rear portions 2a and 2b. That is, a front core 7 is incorporated in the front portion 2a of the bottom wall 2. In the illustrated embodiment, the rear portion 2b of the bottom wall 2 is divided into two regions, forward and backward, and the forward half region has a rear forward half core 8 incorporated therein and the backward half region has a rear backward half core 9 incorporated therein. The front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 have hard cores likewise incorporated therein. Although the front wall 3 has no such hard core incorporated therein, its shape is maintained by the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6. Further, since the rear portions 5b and 6b of the left-hand and right-hand side walls 5 and 6 and the back wall 4 are also held by handrails 10 of the baby carriage body and by frames 11 extending rearwardly of said handrails 10, there is no need to incorporate a hard core therein.
In addition, the front wall 3 has been described as requiring no hard core, but preferably, an elongated core extending along the upper edge of the front wall 3 may be incorporated therein to provide an increased strength.
Two draw links 12 are slidably installed on opposite sides below the bottom wall 2. In FIG. 1, the draw links 12 are shown as forwardly withdrawn.
Referring to FIG. 4, the draw links 12 are inserted in a pair of longitudinally extending tubular members 13 installed on the baby carriage body and are thereby slidably held. A widthwise extending connecting bar 14 and a first widthwise extending connecting belt 15 are connected between the tube members 13. Further, a second widthwise extending connecting belt 16 is connected between the front ends of the draw links 12. A wide belt 17 is installed intermediate between the tube members 13 to extend parallel to the tube members 13 so as to connect the widthwise extending connecting bar 14, first widthwise extending belt 15, and second widthwise extending connecting belt 16. The widthwise extending connecting bar 14, widthwise extending connecting belts 15 and 16, and wide belt 17 contact the lower surface of the bottom wall 2 of the bed 1 to perform the function of auxiliarily supporting the bottom wall 2. The state shown in solid lines in FIG. 4 is one in which the draw links 12 are retracted, with a slack 18 formed in the wide belt 17. When the draw links 12 are forwardly withdrawn as shown in phantom lines in FIG. 4, the slack 18 disappears and the terminal end of the forward withdrawal of the draw links 12 is defined.
The front portions 5a and 6a and the left-hand and right-hand side walls 5 and 6 are constructed so that they are separable from the rear portions 5b and 6a, and separate joint means are provided therefor. For example, zippers 19 are attached along the boundary lines between the front portions 5a, 6a and the rear portions 5b, 6b. Further, the front wall 3 is constructed so that it is separable from the left-hand and right-hand side walls 5 and 6. Zippers 20 are provided along the boundary lines between the front wall 3 and the left-hand and right-hand side walls 5 and 6. The zippers 19 and 20 are fixed in position so that they can be opened from the top.
In addition, as shown in phantom lines in FIG. 1, a hood 21 may be installed to cover a relatively rear region of the bed 1.
In FIG. 1, the draw links 12 are forwardly withdrawn to support the front portions 2a, 5a and 6a of the bottom wall 2 and left-hand and right-hand side walls 5 and 6, and the front wall 3, with the bed 1 assuming its original bed form. That is, the front and rear portions 2a and 2b of the bottom wall 2 are in a substantially horizontal plane.
To change the aforesaid bed form into chair form, the draw links 12 will be rearwardly retracted. The zippers 19 and 20 are then opened. In response thereto, the front portion 2a of the bottom wall 2 is turned downwardly and the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 overlie the downwardly turned front portion 2a of the bottom wall 2. Since the front wall 3 is flexible it may be rolled up as shown in FIG. 3. In addition, to hold the front wall 3 in this rolled state, suitable strings or the like (not shown) may be used. Thus, the front of the bed 1 is opened to enable the bed to be used as a chair. That is, the baby is allowed to project his legs forwardly of the bed 1. At this time, the front portion 2a of the bottom wall 2 and the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 extend along the back sides of the legs for protecting the legs.
In addition, when the bed is changed into a chair form, the backward half region of the rear portion 2b of the bottom wall 2 may be utilized to form a backrest. For example, the arrangement may be such that the rear backward half core 9 rises from the bottom wall 2 and is supported by a support member 22 for forming a backrest.
To restore the bed 1 to its original bed form, the draw links 12 are forwardly withdrawn and then the zippers 19 and 20 are closed.
Referring to the embodiment of FIGS. 5 to 9, the front and rear portions 1a and 1b of the bed 1 are of separable construction. To this end, the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 are arranged to be separable from each other. The front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 are connected to the rear portions 5b and 6b by zippers 23. Further, the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 are connected to the front wall 3 by zippers 24. Further, the front portion 2a of the bottom wall 2 is disposed on a level different from that of the rear portion 2b; for example, in this embodiment, the front portion 2a underlies the rear portion 2b.
More particularly, the front portion 2a of the bottom wall 2 is attached to the upper sides of the draw links 12. The tube members 13, adapted to slidably receive the draw links 12, have slits 25 for receiving, during the slide movement of the draw links 12, the front portion 2a and the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 which are folded to overlie said front portion 2a as will be later described. The rear portion 2b of the bottom wall 2 is fixedly placed on the tube members 13. In addition, to minimize the clearance between the front and rear portions 2a and 2b of the bottom wall 2 which are on different levels, the size of the front portion 2a is such that even when it is forwardly withdrawn to the limit, the rear end of the front portion 2a overlaps with the front end of the rear portion 2b.
When the draw links 12 are forwardly withdrawn and the zippers 23 and 24 are closed, the bed 1 is in its original bed form. To change the bed 1 from this form into chair form, the following operation is involved.
First, as shown in FIG. 6, the zippers 23 and 24 are opened and the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 are folded on the front portion 2a of the bottom wall 2. The front wall 3 is allowed to hang down. In this state, the draw links 12 are rearwardly pushed in. In response thereto, the front portion 2a of the bottom wall 2 and the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 are passed through the slits 25 and received under the rear portion 2b of the bottom wall 2, whereby the state shown in FIG. 9 is obtained in which the front of the bed 1 is opened to enable the bed to be used as a chair.
In addition, when it is desired to restore the chair form to the original bed form, the reverse of the operation described above will be performed.
FIGS. 5 and 9 also show another example of an arrangement for forming a backrest having a back core 26 as the hard core to be incorporated in the back wall 4. Main levers 27 are turnably supported in the rear ends of handrails 10 which are part of the baby carriage body. Below the main levers 27, auxiliary levers 28 are turnably supported in the rear ends of the handrails 10. Rear bed portion support members 29 are held by the main and auxiliary levers 27 and 28 and directly support the rear end of the rear portion 1b of the bed 1. Reclining adjusting links 31 are connected between the main levers 27 and pusher bars 30, the arrangement being such that a change of the bent state of the reclining adjusting links 31 causes a change of the inclined state of the main levers 27. When the main levers 27 are in the horizontal state as shown in FIG. 5, the bottom wall 2 in the rear end portion of the bed 1 supported by the rear bed portion support member 29 is also held horizontal, with the bed assuming its original bed form. When the main levers 27 stand up as shown in FIG. 9, the rear bed portion support members 29 are displaced upwardly and the back wall 4 is raised and so is the portion of the bottom wall 2 having the rear backward half core 9 incorporated therein. As a result, a backrest is formed by the portion having the rear backward half core 9 and by the back wall 4. The auxiliary levers 28 control the attitude of the rear bed portion support members 29; for example, in the FIG. 9 state, they force the rear bed support members 29 to abut against the back of the bottom wall 2 so that the back wall 4 is aligned with the portion having the rear backward half core 9.
The hood 32 mau be installed in position by making use of the rear bed portion support member 29.
In the modification of FIGS. 10, 11, and 12, the front and rear portions 1a and 1b and the bed 1 are formed of separate members. The front portion 1a is held by a pair of draw links 12. The front portion 1a of the bed 1 is made up of the front portions 2a, 5a, and 6a of the bottom wall 2 and left-hand and right-hand side walls 5 and 6 and the front wall 3. The rear portion 1b of the bed 1 is made up of the rear portions 2b, 5b, and 6b of the bottom wall 2 and left-hand and right-hand side walls 5 and 6 and the back wall 4. The front portions 1a of the bed 1 is arranged to overlie the rear portion 1b. Engaging rails 33 are formed along the upper edges of the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6 and engage the upper edges of the rear portions 5b and 6b of the left-hand and right-hand side walls 5 and 6, as best shown in FIG. 12. The front wall 3 is constructed so that it is separable from the front portions 5a and 6a of the left-hand and right-hand side walls 5 and 6, with zippers 34 attached along the boundary lines therebetween. The zippers 34 are adapted to be opened from the top.
In the state shown in FIG. 10, the draw links 12 are forwardly withdrawn to hold the front portion 1a of the bed 1. In this manner, the bed 1 assumes its original bed form.
For changing the bed into a chair form as shown in FIG. 11, the user operates the draw links 12 to retract them rearwardly. In response thereto, the front portion 1a of the bed 1 is rearwardly displaced as guided by the engaging rails 33. In addition, to avoid interference of the region where the draw links 12 are attached to the front portion 2a of the bottom wall 2 with the rear portion 2b of the bottom wall 2 during this operation, the draw links 12 are attached only at their front ends to the front portion 2a of the bottom wall 2. Further, if necessary, a suitable cut may be formed in the front end of the rear portion 2b of the bottom wall 2. To remove the front wall 3 from the front of the bed 1, the zippers 34 are downwardly slid for opening. As a result, the front wall 3 changes down, with the front of the bed 1 being opened to enable the bed to be used as a chair.
While the invention has been described so far with reference to some embodiments thereof, modifications are possible. For example, while the front wall 2 has been treated by being rolled as shown in FIG. 3, it may be allowed to hang down or it may be placed on the front portion 2a of the bottom wall 2. Further, while the front wall 3 has been allowed to hang down as shown in FIG. 6, it may be rolled as shown in FIG. 3 or it may be placed on the front portion 2a of the bottom wall 2. Further, as shown in FIGS. 10 through 12, the front portion 1a of the bed 1 has been constructed to be positioned inside the rear portion 1b, but this arrangement may be reversed. Further, the zippers used in these embodiments may be replaced by other separable joint means such as hooks, buttons, and velvet fasteners.
While the foregoing description has made no mention of the collapsing of the baby carriage, it is possible to obtain a bed which satisfactorily follows the collapsing operation of the baby carriage by selecting suitable materials forming the baby carriage of suitably designing the connections between the materials, such bed being applicable to both collapsible and uncollapsible baby carriages.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | This invention is a baby carriage bed (1) of the so-called "box type" which is basically in the form of a box as a whole comprising a bottom wall (2), a front wall (3), a back wall (4), and left-hand and right-hand side walls (5, 6). In such box-shaped bed (1), when the forwardly disposed walls (2a, 3, 5a, 6a) are displaced to another place and when particularly in the bottom wall (2) its rear portion (2b) alone is left to form the seat of a chair, a chair form is established. To provide the necessary arrangement therefor, a pair of longitudinally slidable draw links (12) are installed on both sides under the bottom wall (2), so that when the draw links (12) are forwardly withdrawn, they hold the front portions (2a, 5a, 6a) of the bottom wall (2) and left-hand and right-hand side walls (5, 6) and the front wall (3). The front portions (5a, 6a) of the left-hand and right-hand side walls (5, 6) are constructed to be separable from the rear portions (5b, 6b). The front portion (2a) of the bottom (2) is constructed so that it can be displaced with respect to the rear portion (2b) for example by sliding or turning. When the draw links (12) are rearwardly retracted, the front portions (2a, 5a, 6a) of the bottom wall (2) and left-hand and right-hand side walls (5, 6) are displaced in such a manner as to open the front of the baby carriage bed to enable the bed to be used as a chair. | 1 |
This application is a continuation of application Ser. No. 796,313 filed Nov. 8, 1985, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for measuring a distance, and more particularly to a method and apparatus for optically measuring a distance to an object.
2. Description of the Prior Art
Measurement of a distance from a measuring device to an object is used for various purposes. For example, in a self-running robot, the distance is measured to recognize a surrounding environment. The robot can run while it avoids confrontation with an article based on the measured information.
The distance may be optically measured. One method thereof is a so-called stereoscopic method. This method is briefly explained below.
FIG. 1B illustrates a principle of the stereoscopic method. Numerals 101 and 102 denote lenses having the same focal distance, and numerals 101A and 102A denote optical axes thereof. The lenses 101 and 102 are arranged such that the optical axes 101A and 102A are parallel to each other and a line (base line) connecting centers of the lenses is orthogonal to the optical axes 101A and 102A. Measuring means 103 is arranged behind the lens 101 at a position spaced by the focal distance F of the lens 101, and measuring means 104 is arranged behind the lens 102 at a position spaced by the focal distance F. The measurement means 103 and 104 are arranged on a line which is parallel to the base line of the lenses 101 and 102.
In FIG. 1A, an object 105 to be measured is at an infinite point on the optical axis 101A. In this case, an image 106 of the object 105 on the measurement means 103 by the lens 101 exists on the optical axis 101A, and an image 107 of the object 105 on the measurement means 104 by the lens 102 exists on the optical axis 102A.
In FIG. 1B, the object 105 is at a point on the optical axis 101A spaced from lens 101 by a definite distance X. In this case, the image 106 of the object 105 on the measurement means 103 by the lens 101 exists on the optical axis 101A but the image 107 of the object 105 on the measurement means 104 by the lens 102 exists at a point spaced from the optical axis 102A.
Accordingly, by detecting a deviation D of the image 107 from the optical axis 102A by the measurement means, the distance X to be measured can be calculated in accordance with the following formula based on a distance F between the lenses 101 and 102 and the measurement means 103 respectively and 104, and the base line length L. ##EQU1##
Since the object to be measured usually has an extension, or finite depth, an image is formed over a certain range on the measurement means. As a result, it is difficult to specify the image at the same point on the same object. In the above stereoscopic method, in order to determine the positions of the images 106 and 107 by the measurement means 103 and 104, an illumination distribution in one measurement means 103 is correlated to an illumination distribution in the other measurement means 104.
FIGS. 2A, 2B and 2C illustrate a principle of the correlation method.
The measurement means 103 and 104 may be CCD arrays which are self-scan type sensors. As is well known, the CCD array comprises a number of finely segmented photo-sensing elements of approximately 10 μm, and can produce an electrical signal representing a degree of illumination of the image detected by the photo-sensing elements, as a time-serial signal in a predetermined sequence.
In FIG. 2A, a CCD array 103 which is the measurement means for the lens 101 has n photo-sensing elements, and a CCD array 104 which is the measurement means for the lens 102 has m photo-sensing elements (m>n). When a distance to the object on the optical axis 101A is to be measured, the image 106 formed by the lens 101 exists on the optical axis 101A regardless of the distance to the object but the image 107 formed by the lens 102 changes its position depending on the distance to the object. Accordingly, the CCD array 104 has more photo-sensing elements than the CCD array 103. In this arrangement, the CCD array 103 is called a standard view field and the CCD array 104 is called a reference view field.
In the arrangement of FIG. 2A, illumination distributions of the standard view field and the reference view field are shown in FIG. 2B. Since a focusing relationship of the object 105 and the image 106 in the optical axis direction to the lens 101 is equal to a focusing relationship of the object 105 and the image 107 on the optical axis direction to the lens 102 (magnifications are equal), the illumination distribution of the image 106 and the illumination distribution of the image 107 are different from each other only in the displacement D.
Accordingly, the CCD arrays 103 and 104 time-serially produce outputs of the photo-sensing elements as shown in FIG. 2C.
In order to correlate the outputs of the two CCD arrays, differences between outputs S 1 -S n of first to n-th photo-sensing elements in the standard view field and corresponding outputs R 1 ˜R n of first to n-th photo-sensing elements in the reference view field are determined. ##EQU2## Similarly, differences between the outputs S 1 ˜S n of the first to n-th photo-sensing elements in the standard view field and corresponding outputs R 2 ˜R n+1 of the second to (n+1)th photo-sensing elements in the reference view field are determined. ##EQU3## Similarly, ##EQU4## is determined.
Of the (m-n+1) values thus determined, the COR number of the smallest value (theoretically zero) is selected and it is multiplied by the width of one photo-sensing element of the CCD array to determine the distance D.
In the determination of the distance D by the correlation method, the standard view field of a certain size and the reference view field larger than the standard view field are necessary.
As seen from the above description, when the distance measurement is to be done over a wide range from an infinite to a near distance, the CCD array for the reference view field is large and requires a large number of photo-sensing elements because the distance D is large in the near distance measurement. This makes the signal processing complex in the correlation method.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method and apparatus for measuring a distance, which resolve the problems encountered in the prior art.
It is another object of the present invention to provide a method of measuring the distance to an object, using an apparatus having two optical systems which have optical axes parallel with each other, and detecting means on which images are respectively formed by said two optical systems comprising; the steps of;
(a) obtaining correlation between illumination distributions of object images formed on said two detecting means;
(b) changing the positional relationships between the respective optical systems and corresponding detecting means on the basis of the correlation obtained in the step (a);
(c) obtaining a positional relationship between said two optical systems and said two detecting means when a desired correlation is obtained in the steps (a) and (b) and
(d) obtaining the distance between an object and said apparatus on the basis of the desired positional relationship obtained in the step (c).
It is another object of the present invention to provide an apparatus for measuring a distance, comprising:
a first optical system;
a second optical system having an optical axis parallel with an optical axis of said first optical system;
first detecting means on which an object image is formed by said first optical system;
second detecting means on which an object image is formed by said second optical system;
first means for changing the positional relationships between said first and second optical systems and said first and second detecting means, respectively to obtain correlation between illumination distributions of said object images formed on said first and second detecting means and to obtain the positional relationships between said first and second optical systems and said first and second detecting means when a desired correlation is obtained; and
second means for obtaining a distance between said object and said apparatus on the basis of the positional-relations obtained by said first means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A, 1B, 2A, 2B and 2C illustrate a principle of distance measurement in a so-called stereoscopic method,
FIGS. 3A and 3B show a distance measurement method of the present invention,
FIG. 4, is a block diagram of an apparatus used in the measurement method of the present invention, and
FIGS. 5, 6 and 7 show the measurement method of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 3A and 3B show one embodiment of the measurement method of the present invention. Numerals 1 and 2 denote lenses having the same focal distance, and numerals 1A and 2A denote the optical axes thereof. The lenses 1 and 2 are arranged such that the optical axes 1A and 2A are parallel to each other and a base line is orthogonal to the optical axes 1A and 2A. Numerals 3 and 4 denote illumination distribution measurement means such as CCD arrays for the lenses 1 and 2, respectively, each of which comprises N photo-sensing elements. The CCD arrays 3 and 4 are spaced from the lenses 1 and 2 by the focal distance F of the lenses 1 and 2, respectively, and arranged on a line parallel to the base line of the lenses.
FIG. 3A shows an original arrangement. An object 5 to be measured is at an infinite point on the optical axis 1A. Images 6 and 7 of the object 5 on the CCD arrays 3 and 4 by the lenses 1 and 2 exist on the optical axes 1A and 2A, respectively. In the arrangement of FIG. 3A, the center photo-sensing elements, that is, the (N/2)th photo-sensing elements from the left ends of the CCD arrays 3 and 4 are on the optical axes 1A and 2A, respectively. In this arrangement, the illumination distributions of the two CCD arrays 3 and 4 are identical.
In FIG. 3B, the object 5 is spaced by a definite distance X on the optical axis 1A. For the arrangement of the lenses 1 and 2 and the CCD arrays 3 and 4 shown in FIG. 3A, the illumination distributions of the CCD arrays 3 and 4 would not be identical. Therefore, in FIG. 3B, the CCD array 4 is moved in a direction normal the optical axis 2A little by little and the matching of the illumination distributions of the two CCD arrays 3 and 4 is detected during the movement. As shown in FIG. 3B, the illumination distributions of the CCD arrays 3 and 4 match each other when the image 7 of the object 5 is focused on the (N/2)th photo-sensing element from the left end of the CCD array 4.
Accordingly, by measuring the displacement D of the CCD array 4 from the initial position to the position at which the illumination distributions match each other, the distance X can be calculated based on the displacement D because the displacement D is proportional to the deviation of the images 6 and 7 from the optical axes 1A and 2A.
FIG. 4 is a block diagram of a signal processor used to practice the present distance measurement method. Numerals 3 and 4 denote the CCD arrays having the same number of photo-sensing elements. Numerals 1A and 2A denote the optical axes of the lenses, not shown. One CCD array 3 is fixed in position while the other CCD array 4 is movable in a direction normal to the optical axis 2A by a drive unit 11. Data readout of the CCD arrays 3 and 4 is driven by a clock control circuit 12 and a drive circuit 13, and the analog data from the CCD arrays 3 and 4 are time-serially supplied to a differential circuit 14 where a time-serial differential signal of the corresponding photo-sensing elements of the CCD arrays 3 and 4 is formed. This differential signal is supplied to an integrator 15.
After the data have been read out while the CCD arrays 3 and 4 are fixed, the drive unit 11 is activated by the clock control circuit 12 and a CCD movement drive circuit 16 so that the CCD array 4 is moved in a direction normal to the optical axis 2A to the right by a small distance ΔD (for example, a distance corresponding to the width of a photo-sensing element of the CCD array). The integrator 15 produces the integrated output as the CCD array is moved, and then the integrator 15 is cleared. The integrator 15 has been initially cleared. The output from the integrator 15 is supplied to an A/D converter 17 where it is converted to a digital signal. The output of the A/D converter 17 is counted by a counter 18 and the count thereof is latched in a latch 19. The latch 19 has been initially cleared.
After the movement of the CCD array 4, the data of the CCD arrays 3 and 4 are read out in similar manner, and the above operation is repeated.
Numeral 20 denotes a comparator which compares an input data A from the counter 18 with a data B from the latch 19, and only if A<B, it updates the data B of the latch by the data A so that the latch 19 holds the data A as the new data B. A matching position detection circuit 21 counts the number of times of movement of the CCD 4. When and only when the comparison result is A<B, the comparator 20 supplies an output to the matching position detection circuit 21. Thus, the detection circuit 21 latches the number of times of movement each time it receives the output from the comparator 20. Finally, the number of times of movement at which the output of the A/D converter 17 is minimum, that is, the integrated output of the integrator 15 is minimum is obtained.
The incremental distance ΔD of the CCD array 4 is supplied to the matching position detection circuit 21, and the number of times for the minimum integrated output, multiplied by ΔD represents the distance (D in FIG. 3B) which the CCD array 4 has been moved before the highest matching of the illumination distribution in the CCD arrays 3 and 4 is reached.
The distance D outputted by the matching position detection circuit 21 is supplied to a distance information signal output circuit 22, which calculates the distance X to the object in accordance with the formula (1). The distance information is supplied to a CPU 23 and stored in a memory 24.
In the present embodiment, only one of the two CCD arrays is moved in a direction normal to the optical axis. Alternatively, the two CCD arrays may be moved. In such case, a formula for calculating the distance is different from that of the present embodiment.
FIG. 5 shows another embodiment of the measurement method of the present invention. Like elements to those shown in FIG. 3 are designated by like numerals. In the present embodiment, the CCD array 3 is moved along the optical axis 1A and the CCD array 4 is moved obliquely to the optical axis 2A. The CCD arrays 3 and 4 are moved such that the CCD arrays 3 and 4 are always spaced from the lenses 1 and 2 in the optical axis direction by the same distance. In FIG. 5, the CCD arrays 3 and 4 which are in the same state as those in FIG. 3A are shown by broken lines. They represent the initial state. In the initial state, if the object is at an infinite point, the illumination distributions of the two CCD arrays completely match to each other.
The CCD arrays 3 and 4 are moved such that a relation
(F+f)/(L+D)=constant
is met between the distances of movement f and D in FIG. 5. In this case, when the illumination distributions on the CCD arrays 3 and 4 completely match each other, the images 6 and 7 of the object 5 are focused onto the CCD arrays 3 and 4, as is derived from a lens formula.
In the present embodiment, by using (F+f) instead of F in the embodiment of FIG. 3, the distance X can be calculated in the same manner.
FIG. 6 shows another embodiment of the measurement method of the present invention. In the present embodiment, instead of moving the CCD array 4, the lens 2 is moved in a direction normal to the optical axis 2A to the left. In this case, (L-D) is used instead of L in the formula (1) to calculate the distance X.
FIG. 7 shows another embodiment of the measurement method of the present invention. In the present embodiment, as the lens 2 is moved, the CCD arrays 3 and 4 are moved along the optical axes 1A and 2A. The lens 2 and the CCD array 3 and 4 are moved such that the relation
(F+f)×(L-D)=constant
is met between the distances of movement f and D of FIG. 7. In the embodiment, when the illumination distributions on the CCD arrays 3 and 4 completely match each other, the object is focused onto the CCD arrays 3 and 4 as is derived from the lens formula.
In the present embodiment, (F+f) is used instead of F in the embodiment of FIG. 6 to calculate the distance X.
In the embodiments of FIGS. 5 and 7, the images are focused onto the CCD arrays. Therefore, the contrast is high and the precision of detection of the matching of the illumination distribution is high. Accordingly, the precision of the distance measurement is improved.
In the above embodiment, the object is on the optical axis of one of the lenses. However, the present invention is also applicable when the object is off the optical axis of the lens. In this case, the distance in the optical axis direction is first calculated in the same manner as that of the above embodiments, and then a distance from the lens to the object is calculated based on an angle made between the direction of the object as viewed from the lens and the optical axis direction. Thus, the present invention allows the distance measurement in a single direction as well as multiple directions.
In the distance measurement method of the present invention, the optical axes of the two lenses are kept in parallel and at least one lens or at least one measurement means is moved, because the magnifications of the two images of one object on the line parallel to the base line of the two lenses are always equal only in such an arrangement.
In accordance with the distance measurement method of the present invention, the measurement of a wide range of distances can be attained with CCD arrays having a small number of photo-sensing elements, and the signal processing is relatively simple. Although, in the above embodiments, the focal length of lens 2 is the same as that of lens 1, the case wherein the focal lengths of lens 1 and 2 may be different from each other the same effect can be obtained. | There is disclosed a method for measuring the distance to an object, using an apparatus having two optical systems which have optical axes parallel with each other, and detecting means on which images are respectively formed by the two optical systems, comprising the steps of:
(a) obtaining correlation between illumination distributions of object images formed on the two detecting means;
(b) changing the positional relationships between the respective optical systems and detecting means on the basis of the correlation obtained in the step (a);
(c) obtaining positional relationship between the two optical systems and the two detecting means when a desired correlation is obtained in steps (a) and (b); and
(d) obtaining the distance between an object and said apparatus on the basis of the desired positional relationship obtained in the step (c). | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit, pursuant to 35 U.S.C. 119(e), of U.S. Provisional Application No. 61/051,280, filed on May 7, 2008, and said provisional application is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to apparatus for handling pipe used in well drilling and servicing operations, particularly in association with inclined or “slant” wells.
BACKGROUND OF THE INVENTION
[0003] Oil and gas wells are typically drilled by rotating a drill bit mounted to the bottom of a “drill string” made up of sections of pipe (also referred to as “joints” or “tubulars”) joined together by means of threaded connections at the ends of each pipe section. After a well has been drilled, the drill string is removed and typically a string of tubular casing sections is installed to line the wellbore, and then a string of production tubing is inserted into the well to carry oil and gas from a subsurface formation up to ground surface. The term “tripping” is commonly used to describe the procedure of adding a tubular to the drill string or production string (“tripping in”) or removing a tubular from the string (“tripping out”). Well drilling and well servicing involve both tripping in and tripping out, for various purposes well known in the field. During tripping operations, tubulars removed from a drill string or production string must be transported to a pipe storage rack of some sort, and/or from the storage rack to the wellbore for connection to the string already in the wellbore.
[0004] There are many known types of apparatus well-suited for carrying out these pipe-handling tasks in association with vertical or near-vertical wells. However, pipe handling is more complicated for tripping operations relating to slant wells, in which the drill string or production string may enter the wellbore at up to 45 degrees or more from vertical.
[0005] U.S. Pat. No. 4,951,759 (Richardson) illustrates some of the challenges associated with tripping pipe oil a slant well, including safety issues associated with the handling of heavy joints of pipe. In accordance with conventional methods, handling tubulars usually requires a person to work on an elevated platform in the mast of the drilling rig or service rig, and to connect a winch line to each tubular as it is tripped out of the well so that it can be moved to a vertical suspended position and then swung away from the mast and into a storage rack. Richardson addresses these requirements with a mast-mounted device that can grasp a tubular while inclined parallel to the mast, and then rotate it away from the mast and deposit in on a horizontal storage rack. The mast-mounted pipe-handling device of Richardson must be either installed on a purpose-built rig where the device is accommodated into the design, or retrofitted to an existing rig, which would entail extensive and expensive modifications.
[0006] Accordingly, there remains a need for improved pipe handling apparatus, particularly for use in drilling and servicing slant wells. More particularly, there is a need for such improved apparatus that is readily usable with conventional drilling rigs and service rigs, without need for significant or any modification to the rigs. The present invention is directed to these needs.
SUMMARY OF THE INVENTION
[0007] In general terms, the apparatus of the present invention is a pipe handling unit comprising a pipe manipulation mechanism mounted to a mobile pipe storage rack, which can be parked adjacent to a drilling rig or service rig and which can pick up tubulars from the rig mast and position them in selected positions in a horizontal storage rack. The pipe manipulation mechanism provides for variable and selective pipe travel paths between the rig mast and the storage rack, such that precise positioning relative to the rig is not critical, thus providing greater flexibility in field-positioning of the pipe handling unit to avoid interference with wellhead equipment, flow lines, shacks, and other wellsite appurtenances. The pipe handling unit does not require an elevated work platform, and thus eliminates safety risks associated with such platforms.
[0008] The pipe manipulation mechanism incorporates grapple means for grasping a section of pipe, with actuation means whereby the mechanism can transport a section of pipe from a vertical or inclined rig mast to the pipe storage rack (i.e., tripping out), or from the storage rack to the rig (i.e., tripping in). The mobile storage rack preferably will accommodate storage of pipe sections in a horizontal or near-horizontal position, with vertical “finger racks” to facilitate pipe placement in desired locations within the rack. Racking the pipes horizontally rather than vertically eliminates the need to guy the rig mast in many situations, thus leading to much faster rig-up and rig-down times. However, horizontal pipe storage is not essential to the invention; the apparatus could also be adapted for use with non-horizontal pipe storage racks.
[0009] The mobile storage rack preferably has adjustable downriggers or stabilizing legs which may be extended to bear on the ground surface and carry up to the full weight of the unit as necessary to level and stabilize the storage rack and thus facilitate accurate positioning of pipe within the rack. Downriggers may be of any suitable type, such as those commonly used in association with mobile cranes. Although the present invention does not require the use of downriggers of any particular type (or at all), preferred embodiments comprise a downrigger stabilizer system incorporating means for laterally shifting or slewing the pipe manipulation mechanism relative to the rig mast and wellhead after the unit has been parked, thus minimizing or eliminating the need for comparatively precise positioning of the pipe handling unit relative to the rig.
[0010] The pipe handling unit preferably includes a self-contained hydraulic power unit to actuate the pipe manipulation mechanism so as to manipulate pipe joints with optimal speed and efficiency to achieve pipe-handling cycle times that are at least as fast as those achieved using conventional methods and equipment. In alternative embodiments, however, power for actuating the pipe manipulation mechanism may be provided from a suitable auxiliary power unit, which may be but is not limited to a hydraulic power unit.
[0011] The pipe handling unit of the present invention is readily adaptable to automated control and operation, using known technologies such as but not limited to microprocessors and programmable logic controllers (PLCs), which are well known in the art. Automated operation is particularly advantageous for embodiments having vertical finger racks, as a computerized control system can readily determine and store in memory the positions of individual pipes within the storage rack and actuate the pipe manipulation mechanism to retrieve pipes from the storage rack in an automatic mode, thereby facilitating pipe handling without the pipes needing to be manually handled or manipulated.
[0012] Control of the pipe handling unit may be from a simple control panel that could be remotely mounted near the rig operator's control panel. The control system may include a set-up mode and an operational mode, with control of the unit being handled primarily by a PLC or other suitable programmable device to enable semi- or fully-automated tripping operations, depending on the desired level of operational integration with the rig.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Embodiments of the invention will now be described with reference to the accompanying figures; in which numerical references denote like parts, and in which:
[0014] FIG. 1 is an isometric view of a pipe handling unit in accordance with the present invention, shown parked alongside a conventional service rig.
[0015] FIG. 2 is a rear view of a pipe handling unit positioned beside a service rig as shown in FIG. 1 .
[0016] FIG. 3A is a side view illustrating the pipe handling unit of FIGS. 1 and 2 , shown alongside a service rig with its mast in the vertical position.
[0017] FIG. 3B is a side view illustrating the pipe handling unit of FIGS. 1 and 2 , shown alongside a service rig with its mast in an inclined position.
[0018] FIG. 4 is a partial plan of the pipe handling unit as in FIG. 3A , showing various possible positions of the unit's pipe manipulation mechanism as it transports a pipe section to or from the service rig mast.
[0019] FIG. 5A is a side view of the pipe handling unit, showing various possible positions of the pipe manipulation mechanism as it moves a pipe section to or from the unit's pipe storage rack.
[0020] FIG. 5B is a side view illustrating mechanisms for actuating the pipe manipulation mechanism in accordance with one embodiment of the invention.
[0021] FIG. 6 is a partial rear view of the pipe handling unit showing representative positions of the pipe manipulation mechanism as it places or retrieves a pipe section in or from the pipe storage rack.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] In preferred embodiments as illustrated in the Figures, the pipe handling unit 100 of the present invention comprises a pipe manipulation mechanism (generally indicated by reference numeral 50 ) mounted to a mobile pipe storage rack which may be positioned as required adjacent to a drilling rig or service rig 1 having a mast 2 . Rig 1 does not form part of the broadest embodiments of the present invention. In the illustrated embodiments, the mobile storage rack is provided in the form of a trailer 10 , adapted to be transported and maneuvered as required by a suitable tractor unit (not shown). In alternative embodiments, mobile pipe storage rack may be a self-propelled unit with its own motor and drive train. Trailer 10 is preferably provided with front downrigger stabilizer legs 11 and rear downrigger stabilizer legs 12 which may be deployed to lift trailer 10 off of its tires 13 , whereupon stabilizer extension slides (not shown) may be used to position trailer 10 as appropriate adjacent to service rig 1 and then trailer 10 is levelled.
[0023] Trailer 10 has a flat deck 10 A which serves as a pipe storage area or storage rack 60 . In preferred embodiments, one or more sets of vertical dividers or “finger racks” 14 extend upward from deck 10 A, preferably with one set of finger racks 14 F near the front end of trailer 10 and a second set of finger racks 14 R near the rear end of trailer 10 as shown in FIG. 1 , to facilitate orderly storage of pipe sections 15 as they are tripped out of the well and stored pending their return to the well (“tripping in”) in accordance with typical well-servicing operations. The space between adjacent finger racks will be sized to receive a single pipe section, and finger racks 14 preferably will be adjustable to accommodate different pipe diameters. Preferably, the space between adjacent finger racks will be in the range of 1.5 to 1.8 times the pipe diameter, or less. To minimize weight trailer 10 will typically be designed only to carry racked pipe sections 15 while trailer 10 is supported in a stationary position on stabilizer legs 11 and 12 . However, alternative embodiments may be designed for highway transport of racked pipe sections 15 .
[0024] FIG. 1 shows pipe handling unit 100 positioned adjacent to a service rig 1 which has been configured to service a slant well having a wellhead 3 protruding from the ground (conceptually indicated by reference character G). In a typical application, service rig 1 uses a travelling block 5 , which is longitudinally movable along mast 2 , to lift a string of jointed pipe 4 (e.g., a production string) out of the well using an elevator (not shown) of well-known type. When the elevator and travelling block 5 are not supporting the weight of pipe string 4 , the weight is carried by slips 7 associated with wellhead 3 (in accordance with well-known technologies). In FIG. 1 , a pipe section 15 has been disconnected from pipe string 4 , and is being grasped by grapple means 30 associated with pipe manipulation mechanism 50 , with pipe string 4 being supported by slips 7 .
[0025] In preferred embodiments, pipe handling unit 100 incorporates an engine-driven hydraulic power unit (conceptually indicated by reference numeral 32 ) mounted to trailer 10 , to provide pressurized hydraulic fluid for actuation of pipe manipulation mechanism 50 . Preferred embodiments also incorporate a control system for pipe manipulation mechanism 50 , also mounted on trailer 10 as conceptually indicated by reference numeral 33 . However, alternative power means and control systems, including non-trailer-mounted and remotely-operated alternatives, may be used without departing from the concept and scope of the present invention.
[0026] FIG. 2 illustrates service pipe handling unit 100 positioned adjacent to rig 1 as in FIG. 1 , but viewed from the rear. In the embodiment shown in FIG. 2 , pipe manipulation mechanism 50 comprises a main boom 19 which is rotatably mounted to trailer 10 as described in greater detail below. Main boom 19 will typically be mounted to the rear end of trailer 10 , and preferably offset from the trailer's longitudinal centerline as shown in FIG. 2 , for optimal accessibility to an adjacent rig 1 . A boom extension 21 is slidably or telescopically mounted to main boom 19 for increased access to upper regions of mast 2 of rig 1 .
[0027] As best appreciated with reference to FIGS. 2 , 5 , and 6 , pipe manipulation mechanism 50 further includes an inner swivel arm 23 having an inner end 23 A and an outer end 23 B, with inner arm 23 being mounted along its inner end 23 A to boom extension 21 so as to be swivellable about a first swivel axis X- 1 parallel to main boom 19 . An inner arm actuator 24 is provided for swivelling inner arm 23 about first swivel axis X- 1 as necessary. Pipe manipulation mechanism 50 further comprises an outer swivel arm 25 having an inner-end 25 B and an outer end 25 C, with outer swivel arm 25 being mounted along its inner end 25 B to outer end 23 B of inner swivel arm 23 so as to be swivellable about a second swivel axis X- 2 parallel to first swivel axis X- 1 (and, therefore, parallel to main boom 19 ). An outer swivel arm actuator 26 is provided for swivelling outer swivel arm 25 about second swivel axis X- 2 as necessary.
[0028] As indicated in the Figures, inner swivel arm 23 and outer swivel arm 25 may be of substantial width in the direction parallel to axes X- 1 and X- 2 , and in preferred embodiments may be provided in the form of trussed frames as shown. However, this is only one of many possible configurations for inner swivel arm 23 and outer swivel arm 25 , and the present invention is not limited to any particular form or structure for these components.
[0029] As perhaps best seen in FIGS. 3A , 3 B, and 5 A, an elongate axial slide member 28 is mounted to outer swivel arm 25 along outer end 25 C thereof, so as to be selectively movable along and relative to outer swivel arm 25 in a direction parallel to second swivel axis X- 2 (and, therefore, parallel to main boom 19 ), to facilitate even greater access to upper regions of mast 2 of rig 1 . This functionality can be appreciated from FIGS. 3A and 3B , in which slide member 28 is in it lowermost axial position relative to outer swivel arm 25 , and from FIG. 5A in which slide member 28 is in its uppermost axial position relative to outer swivel arm 25 . Provided near each end of slide member 28 are grapples of any type suitable for grasping a section of pipe, whether from mast 2 or from pipe storage rack 60 . An additional function of slide member 28 is to position grapples 30 so that they do not interfere with finger racks 14 when pipe manipulation mechanism 50 is depositing a pipe section 15 into storage rack 60 .
[0030] As shown in FIG. 5A , main boom 19 is rotatably mounted to trailer 10 such that it can be rotated from a lowered position in which it is substantially parallel to deck 10 A of trailer 10 , to a fully-raised position (which typically but not necessarily will be the vertical position shown in FIG. 3A ), with the ability to stop at any intermediate position between these extremes so as to be substantially parallel to mast 2 of a drilling rig or service rig with which pipe handling unit 100 is being used. In the preferred but non-limiting embodiment shown in FIG. 5B , this functionality is enabled by a providing a lower boom member 19 the lower end 19 L of which is mounted to trailer 10 so as to be rotatable about a first horizontal axis X- 3 transverse to the longitudinal axis of trailer 10 , and mounting the lower end 17 L of main boom 17 to the upper end 19 U of lower boom member 19 so as to be rotatable about a second horizontal axis X- 4 parallel to first horizontal axis X- 3 . The rotational position of lower boom member 19 relative to trailer 10 is controlled by a lower boom actuator 18 (shown in FIG. 5B in the exemplary form of a hydraulic cylinder), and the rotational position of main boom 17 is controlled by an upper boom actuator 20 (shown in FIG. 5B in the exemplary form of a hydraulic cylinder with an associated mechanical linkage 22 ). Persons skilled in the art of the invention will appreciate that various other mechanisms may be devised to effect the desired functionality of main boom 17 , with or without a lower boom member 19 , and using hydraulic cylinders or other known types of actuators, without departing from the scope of the present invention.
[0031] Field operation of a pipe handling unit 100 in accordance with the present invention may be readily understood having regard to the Figures and the foregoing description. With trailer 10 positioned substantially parallel to a drilling rig or service rig 1 (as the case may be), with mast 2 of rig 1 being angularly oriented as required (i.e., vertical or inclined), main boom 17 is rotated upward until it is substantially parallel to tie axis of mast 2 . Inner and outer swivel arm actuators 24 and 26 may then be operated as required to rotate slide member 28 to a position allowing grapples 30 to engage and grasp a pipe section 15 disposed within mast 2 (after removal from a drill string or production string), in conjunction with any appropriate adjustment of the axial position of slide member 28 relative to outer swivel arm 25 . This process can then be reversed to rotate pipe section 15 out of mast 2 (as may be particularly well understood with reference to FIGS. 4 and 5A ), for deposition into storage rack 60 as shown in FIG. 6 (again, adjusting the axial position of slide member 28 as appropriate for optimal positioning of pipe section 15 in storage rack 60 ).
[0032] It will be appreciated from FIG. 4 in particular that boom extension 21 can start moving downward along main boom 17 as soon as pipe section 15 has begun rotating out of and away from mast 2 . This feature reduces pipe-handling cycle time compared to prior art pipe-handling equipment which due to structural constraints requires the pipe to be rotated fully out of the mast before rotation to a lower position can begin.
[0033] The foregoing describes the tripping-out procedure; for tripping-in operations, the process is simply reversed. During tripping-in operations, slide member 28 may be actuated to facilitate “stabbing” each added pipe section 15 into the upper end of pipe string 4 for thread makeup, thus minimizing or eliminating the need to use the rig's travelling block and elevator, and reducing the tripping-in cycle time as a result.
[0034] FIG. 6 further illustrates how pipe sections 15 may be deposited on storage rack 60 , guided by finger racks 14 which facilitate orderly arrangement of pipe sections 15 and optimal pipe storage capacity. Grapples 30 are preferably adapted to release and pick up pipe sections from storage rack 60 one at a time without colliding with other pipe sections already in the rack. In order to do this most efficiently, pipe sections 15 can be laid down in and retrieved from horizontal layers, laying the pipe sections down from right to left (as viewed in FIG. 6 ) and picking them up from left to right. In order to move pipe sections 15 in and out of the fingers of finger rack 14 , pipe manipulation mechanism 50 must lift and lower the pipe sections 15 in a vertical movement. However, this movement can be readily achieved by coordinated operation of inner swivel arm actuator 24 and outer swivel arm actuator 26 , preferably in association with a programmed control mechanism, to manipulate inner swivel arm 23 and outer swivel arm 25 so as to produce the required vertical movement of slide member 28 and, in turn, a pipe section 15 held in grapples 30 .
[0035] In preferred embodiments, the various actuators required to operate pipe manipulation mechanism 50 are hydraulically actuated and hydraulically controlled by use of suitable valves, which are in turn controlled by one or more PLCs or other programmable controllers or computers, based on control algorithms using control inputs from one or more sensors (not shown) of known types and applicability. Such sensors may include, but are not limited to, linear and rotational absolute position transducers, hydraulic fluid pressure transducers, proximity sensors, and other position-sensing technologies.
[0036] Preferred embodiments of pipe manipulation mechanism 50 may further comprise grapple extension means (not shown) for facilitating alignment of grapples 30 with a pipe section 15 disposed within the mast of a drilling rig or service rig. Such grapple extension means would be adapted to selectively extend one or both grapples (in concert, independently, or differentially) in a radial direction relative to slide member 28 , so as to bring grapples 30 into optimal alignment with pipe section 15 , even though the axis of slide member 28 might not be precisely parallel to the axis of the well (and pipe section 15 ). Accordingly, the apparatus can be adapted such that if grapples 30 are not optimally aligned with pipe section 15 , the first grapple 30 to contact pipe sections 15 will not push it out of position, or if the pipe is constrained, it will not pull on outer swivel arm 25 . Preferably, the control system of the apparatus will be programmed such that the first grapple contacting the pipe will sense, the contact and stop, allowing (and triggering) the other grapple to move into contact with pipe. Once both grapples 30 are in contact with the pipe, the gripping pressure applied by both grapples may be increased to an appropriate level before lifting the pipe. Persons of ordinary skill in the art will readily appreciate that the above-described functionality of the grapple extension means can be provided in a variety of ways using well-known technologies, such as (but not limited to) limit switches, linear potentiometer detection of position coupled with pressure or force transducer-generated inputs to PLC, or microprocessor-based automated control systems.
[0037] While preferred embodiments have been shown and described herein, modifications thereof can be made by one skilled in the art without departing from the scope and teaching of the present invention, including modifications which may use equivalent structures or materials hereafter conceived or developed.
[0038] The described and illustrated embodiments are exemplary only and are not limiting. For example, the illustrated embodiment of pipe manipulation mechanism 50 features two swivel arms (inner swivel arm 23 and outer swivel arm 25 ) with associated actuators 24 and 26 . However, it will be readily appreciated by persons skilled in the art that alternative embodiments may include three or more swivel arms and corresponding actuators without departing from the concept and scope of the present invention.
[0039] It is to be especially understood that the substitution of a variant of a claimed element or feature, without any substantial resultant change in the working of the invention, will not constitute a departure from the scope of the invention. It is to also be fully appreciated that the different teachings of the embodiments described and discussed herein may be employed separately or in any suitable combination to produce desired results.
[0040] In this patent document, any form of the word “comprise” is to be understood in its non-limiting sense to mean that any item following such word is included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one such element. Any use of any form of the terms “connect”, “engage”, “couple”, “attach”, or any other term describing an interaction between elements is not meant to limit the interaction to direct interaction between the subject elements, and may also include indirect interaction between the elements such as through secondary or intermediary structure. Relational terms such as “parallel”, “perpendicular”, “coincident”, “intersecting”, and “equidistant” are not intended to denote or require absolute mathematical or geometrical precision. Accordingly, such terms are to be understood as denoting or requiring substantial precision (e.g., “substantially parallel”) unless the context clearly requires otherwise. | A pipe handling unit particularly adaptable for use in association with slant wells includes a pipe manipulation mechanism mounted to a mobile pipe storage rack, which when sited adjacent to a drilling rig or service rig can transport pipe sections to or from the rig mast regardless of the angular orientation of the rig mast. The pipe manipulation mechanism includes a boom rotatably mounted to the storage rack, with two or more swivel arms mounted to the mast, with pipe grapple means connected to the outboard end of the swivel arms may be swivelled outward, about axes parallel to the boom, to a position in which the grapple means can grasp a pipe section held in the rig mast. The swivel arms may then be swivelled in the opposite rotation to rotate the pipe away from the mast. The boom and swivel arms are then manipulated in coordinated fashion to deposit the pipe section in the storage rack. | 4 |
This is a continuation of application Ser. No. 08/181,818, filed Jan. 18, 1994 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to handles, and specifically to handles or grips which are attachable to keys to facilitate their use.
2. Description of Prior Developments
Keys of the type widely used for operating locks found in the doors of homes, offices, vehicles and other applications are generally planar or laminal in form. Such keys typically include a base, which is often perforated and which provides a surface for gripping and turning the key, and an integrally formed shaft projecting from the base. Integrally formed on the shaft is a series of irregularities, such as teeth, which are configured to correspond to the mating elements of the lock when inserted therein.
The act of gripping and turning the key base requires the pads of several fingers to be placed together in close proximity in a pincer-like or pinching fashion. The planar form of the key and key base is not chosen primarily for ease of use but to enable inexpensive manufacture, coding and compact storage of several keys as on a single key ring.
In general, prior key holders included various key attachments for containing one or more keys and for aiding in identifying and selecting individual keys. These prior attachments take advantage of the compact planar form of the typical key by making the key cases and holders substantially planar as well.
Prior key cases and holders are typically made laminal as suggested by the flat keys with which they are used. Also transferred from the key to the key holder is the requirement that the key user's fingers assume a pincer-like position to grip and twist the device holding the key. Arthritis and other debilitating medical conditions can impair digital dexterity and cause such a pinching, twisting action to be painful, awkward or even impossible to perform.
Many devices, such as eating utensils and writing instruments, have been specifically designed to minimize discomfort and enable their usage by persons afflicted as mentioned above. However, there yet appears to be a need for a device to allow the easier use of a common key.
The act of pinching a planar object often causes longer fingernails to come into contact with one another, the key, the lock or an adjacent object. This contact can damage or ruin any cosmetic treatment which has been applied to the fingernails or cuticles.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a key grip with which the required grasping and turning action can be accomplished with the hand in a more relaxed and comfortable position and which allows the action to be performed using a greater area of the fingers as well as the palm of the hand, thereby reducing the required gripping effort.
A further object of the invention is the reduction of the tangential or twisting forces required to turn a key by virtue of increasing the turning radius upon which the fingers and palm act.
Still another object of the invention is to preclude the necessity or minimize the possibility of bringing the fingertips and fingernails into close proximity with one another and with other objects which, if touched, would damage the surface or edge of the fingernail.
Yet another object of the invention is to allow a plurality of attachment positions to accommodate different key sizes, hole locations and lock configurations.
A further object of the invention is to allow the pivotable mounting of the key with respect to the handle.
Still another object of the invention is to provide surface discontinuities to enable still easier grasping and turning of the handle.
An additional object of the invention is to provide a hole or ring to allow attachment of the invention to a conventional keyring or keychain.
The aforementioned objects, features and advantages of the invention will, in part, be pointed out with particularity, and will, in part, become obvious from the following more detailed description of the invention, taken in conjunction with the accompanying drawings, which form an integral part thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of a unitary handle embodiment of the invention.
FIG. 1A is a sectional view of FIG. 1 taken along line 1A--1A of FIG. 1.
FIG. 1B is a sectional view of the slot of a second unitary embodiment of the invention.
FIG. 1C is a third unitary embodiment of the invention.
FIG. 2 is an exploded view of a two-piece embodiment of the invention.
FIG. 2A is a sectional view of a second two-piece embodiment.
FIG. 2B is a perspective view of a hinged, one-piece embodiment of the invention.
FIG. 3 is a sectional view of a polyhedral embodiment of the invention showing concave and convex polyhedral surfaces.
FIGS. 4, 4A, 4B and 4C are views of embodiments of the invention employing surface discontinuities.
FIG. 5 is a side view showing an embodiment of the invention with adjustable attachment positions.
FIG. 6 is a side view of a pivotally mounted handle.
FIG. 7 is a side view showing a truncated embodiment with adjustable attachment positions.
In the various figures of the drawings, like reference characters designate like parts.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a basic version of a substantially completely spheroidal key handle or grip constructed in accordance with the present invention. The handle is illustrated as a sphere or spheroid 1 composed of a solid, preferably resilient material such as plastic or rubber. The handle may be symmetric about its axis of rotation or may be asymmetric, as the user may find ergonomically desirable. The material may vary in hardness to the preference of the user, but a high coefficient of friction to enable easy grasping of the handle is usually desirable.
As shown in FIG. 1, oriented along a meridian of spheroid 1 is a slot 2 designed to accommodate the base of a key 3 to be attached to the handle. The slot, which is formed as a recess in a front portion of the spheroid body may be oriented toward the center of the handle or offset from it. If a sufficiently compliant material is used, the walls 4 adjacent to the slot 2, as shown in FIG. 1A, may be partially or entirely in contact or tangent to one another before the insertion of the key base into the slot. This wall contact results in the resilient, biased gripping of the key base as the key resiliently separates the walls 4 as the key is forced between the walls of the slot. Additionally, as shown in FIG. 2, the walls which extend along the slot provide a torque transmitting key attachment structure and may be coated or lined with an adhesive or yielding substance 5, such as double-sided adhesive foam tape, to improve retention and stability of the key base within the key slot. The rear hemispherical portion of the spheroid body opposite the slotted front portion provides a hand engagement surface.
Also, a thermoexpansive material or arrangement of materials may be used in the slot area or for the entire handle, this allowing easier insertion of a key when the handle is cooled as in the freezer compartment of a common refrigerator, but providing increased clamping or retention force when the handle assembly is allowed to return to room temperature.
As shown in FIG. 1B, a series of resilient directional or nondirectional ridges 6, teeth or the like can be inwardly oriented from each wall to allow easy insertion of the key base into the slot, yet provide firm hook-like key retention and require significantly higher force and/or deformation of the slot to remove the key.
Although such an interference retention of the key base within the slot may alone be sufficient, additional gripping or retention may be desirable. For example, in FIGS. 1 and 1C, screw 7 may be inserted through hole 10 which runs perpendicular to the plane of slot 2. Key base 3 is then inserted into slot 2 so that a perforation 11 is axially aligned with hole 10. Hole 10 may be elongated as shown to allow for a plurality of attachment locations. The screw 7 is then passed through perforation 11 and continues through hole 10 until it emerges on an exposed surface of or groove in spheroid 1 where a nut 9 may be applied and tightened to provide a clamping force for retention of the key. Hole 10 could also be tapped to receive screw 7 or a self-tapping screw may be used as in FIG. 1A. Such embodiments also allow the pivoting of the key base 3 about screw 7. Of course, many different types of fasteners may be used.
FIG. 2 shows an exploded view of a two-part embodiment in which two hemispheric sections 12,13 enclose the base of the key 3 when fastened together over it. Barbed projections 14 extending from the symmetric hemispheric sections can be used to retain the section together by mating with corresponding holes 15, as could conventional fasteners. The hemispheric sections can be hinged as well, as shown in FIG. 2B.
FIG. 3 shows a sectional view of a handle 16 in the form of a polyhedron displaying six or more sides. Embodiments with concave 23 and convex 24 meniscus faces are also shown in phantom.
FIGS. 4, 4A, 4B and 4C show two configurations of surface irregularities. FIG. 4 shows meridional fins of varying depths. FIG. 4A shows an array of nubs or projections located on the surface of the handle. FIG. 4B shows a series of depressions. FIG. 4C shows a series of convex projections.
FIGS. 5 and 7 show two additional embodiments of the invention which allow for variable positioning of the attachment point of the fastener and, thus, attachment of the key with respect to the handle. FIG. 7 includes a planar surface portion or truncation 25 with a slot formed in the planar surface portion of the handle in which slot 21 is straight. FIG. 7A shows a top plan view of the handle of FIG. 7, including slot 2 in planar surface portion 25. Slot 22 in FIG. 5 is angled with respect to the centerline of slot 2, shown in phantom, to provide a yet higher degree of variability in positioning.
FIG. 6 shows a pivotable embodiment of the invention. As the handle is turned, with the center of the handle pivoted away, it can orbit about the center of rotation of the lock, further increasing the effective moment arm and turning radius.
As can now be appreciated, the bulbous handle of the invention provides a much more easily used and desirable method and apparatus for turning a key than the direct grasping of either the key itself or of a key held by a substantially flat or planar holding device. Although generally spheroidal handles have been disclosed which define hand-engaging surfaces having substantially arcuate surfaces in three dimensions, it is of course possible to modify the handles to other similar shapes such as oblate spheroids and the like. It is preferable, however, to maintain a generally bulbous shape, such as that of a common doorknob or discus, wherein the aspect ratio of the length of the handle along the axis of key turning rotation, i.e. an axis extending centrally through the handle, with respect to the maximum width of the handle perpendicular to that axis is within a range of about 0.1 to 1.8 and preferably 0.5 to 1.5. This ensures an adequate turning radius and provides substantial engagement with the user's hand while separating the finger nails and protecting them from damage.
Obviously, numerous modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A bulbous hand grip facilitates the turning of a key within a lock by increasing the turning radius through which the key is turned, as well as providing finger and hand surfaces which may be utilized during turning. The hand grip may include a substantially arcuate or spheroidal surface contour. The key may be secured within the hand grip by elastic deformation forces and/or by conventional fasteners. | 4 |
FIELD OF THE INVENTION
The present invention relates to an improved cushioning member and method of making the same, and more particularly to a fluid filled bladder having controlled flex tensile members which allows for the formation of complex-curved contours and shapes while minimizing the amount of surrounding foam material. The present invention also relates to footwear wherein the bladder with controlled flex tensile members is used as a cushioning device within a sole.
BACKGROUND OF THE INVENTION
Considerable work has been done to improve the construction of cushioning members which utilize fluid filled bladders such as those used in shoe soles. Although with the recent developments in materials and manufacturing methods, fluid filled bladder members have greatly improved in versatility, there remain problems associated with obtaining optimum performance and durability. Fluid filled bladder members are commonly referred to as “air bladders,” and the fluid is generally a gas which is commonly referred to as “air” without intending any limitation as to the actual gas composition used.
Closed-celled foam is often used as a cushioning material in shoe soles and ethylene-vinyl acetate copolymer (EVA) foam is a common material. In many athletic shoes, the entire midsole is comprised of EVA. While EVA foam can easily be cut into desired shapes and contours, its cushioning characteristics are limited. One of the advantages of gas filled bladders is that gas as a cushioning compound is generally more energy efficient than closed-cell foam. This means that a shoe sole comprising a gas filled bladder provides superior cushioning response to loads than a shoe sole comprising only foam. Cushioning generally is improved when the cushioning component, for a given impact force, spreads the impact force over a longer period of time, resulting in a smaller impact force being transmitted to the wearer's body. Even shoe soles comprising gas filled bladders include some foam, and a reduction in the amount of foam will generally afford better cushioning characteristics.
Some major engineering problems associated with the design of air bladders formed of perimeter barrier layers include: (I) obtaining complex-curved, contoured shapes without the formation of deep peaks and valleys in the cross section which require filling in or moderating with foams or plates; (ii) ensuring that the means employed to give the air bladder its complex-curved, contoured shape does not significantly compromise the cushioning benefits of air; and (iii) reducing fatigue failure of the bladders caused by cyclic folding of portions of the bladder.
The prior art is replete with attempts to address these difficulties, but often presenting new obstacles in the process of addressing these problems. Most of the prior art discloses some type of tensile member. A tensile member is an element associated with the bladder which ensures a fixed, resting relation between the top and bottom barrier layers when the air bladder is fully inflated, and which often is in a state of tension while acting as a restraining means to maintain the general form of the bladder.
Some prior art constructions are composite structures of air bladders containing foam or fabric tensile members. One type of such composite construction prior art concerns air bladders employing an open-celled foam core as disclosed U.S. Pat. Nos. 4,874,640 and 5,235,715 to Donzis. These cushioning elements do provide latitude in their design in that the open-celled foam cores allow for complex-curved and contoured shapes of the bladder without deep peaks and valleys. However, bladders with foam core tensile members have the disadvantage of unreliable bonding of the core to the barrier layers. FIGS. 1 and 2 illustrate a cross section of a prior art bladder 10 employing an open-celled foam core 12 as a tensile member. FIG. 2 illustrates the loaded condition of bladder 10 with load arrows 14 . One of the main disadvantages of bladder 10 is that foam core 12 gives the bladder its shape and thus must necessarily function as a cushioning member which detracts from the superior cushioning properties of air alone. One reason for this is that in order to withstand the high inflation pressures associated with air bladders, the foam core must be of a high strength which requires the use of a higher density foam. The higher the density of the foam, the less the amount of available volume in the bladder for gas. Consequently, the reduction in the amount of gas in the bladder decreases the benefits of gas cushioning.
Even if a lower density foam is used, a significant amount of available volume is sacrificed which means that the deflection height of the bladder is reduced due to the presence of the foam, thus accelerating the effect of “bottoming out.” Bottoming out refers to the premature failure of a cushioning device to adequately decelerate an impact load. Most cushioning devices used in footwear are non-linear compression based systems, increasing in stiffness as they are loaded. Bottoming out is the point where the cushioning system is unable to compress any further. Also, the elastic foam performs a significant portion of the cushioning function and is subject to compression set. Compression set refers to the permanent compression of foam after repeated loads which greatly diminishes its cushioning aspects. In foam core bladders, compression set occurs due to the internal breakdown of cell walls under heavy cyclic compression loads such as walking or running. The walls of individual cells constituting the foam structure abrade and tear as they move against one another and fail. The breakdown of the foam exposes the wearer to greater shock forces.
Another type of composite construction prior art concerns air bladders which employ three dimensional fabric as tensile members such as those disclosed in U.S. Pat. Nos. 4,906,502 and 5,083,361 to Rudy, which are hereby incorporated by reference. The bladders described in the Rudy patents have enjoyed considerable commercial success in NIKE, Inc. brand footwear under the name Tensile-Air® and Zoom™. Bladders using fabric tensile members virtually eliminate deep peaks and valleys, and the methods described in the Rudy patents have proven to provide an excellent bond between the tensile fibers and barrier layers. In addition, the individual tensile fibers are small and deflect easily under load so that the fabric does not interfere with the cushioning properties of air.
One shortcoming of these bladders is that currently there is no known manufacturing method for making complex-curved, contoured shaped bladders using these fabric fiber tensile members. The bladders may have different heights, but the top and bottom surfaces remain flat with no contours and curves. FIGS. 3 and 4 illustrate a cross section of a prior art bladder 20 employing a three dimensional fabric 22 as a tensile member. FIG. 4 illustrates the loaded condition of bladder 20 with load arrows 24 . As can be seen in FIGS. 3 and 4, the surfaces of bladder 20 are flat with no contours or slopes.
Another disadvantage is the possibility of bottoming out. Although the fabric fibers easily deflect under load and are individually quite small, the sheer number of them necessary to maintain the shape of the bladder means that under high loads, a significant amount of the total deflection capability of the air bladder is reduced by the volume of fibers inside the bladder and the bladder can bottom out.
One of the primary problems experienced with the fabric fibers is that these bladders are initially stiffer during initial loading than conventional gas filled bladders. This results in a firmer feel at low impact loads and a stiffer “point of purchase” feel than belies their actual cushioning ability. This is because the fabric fibers have a relatively low elongation to properly hold the shape of the bladder in tension, so that the cumulative effect of thousands of these relatively inelastic fibers is a stiff effect. The tension of the outer surface caused by the low elongation or inelastic properties of the tensile member results in initial greater stiffness in the air bladder until the tension in the fibers is broken and the solitary effect of the gas in the bladder can come into play which can affect the point of purchase feel of footwear incorporating bladder 20 . The Peak G curve, Peak G v. time in milliseconds, shown in FIG. 5 reflects the response of bladder 20 to an impact. The portion of the curve labeled 26 corresponds to the initial stiffness of the bladder due to the fibers under tension, and the point labeled 28 indicates the transition point in which the tension in the fibers of fabric 22 are “broken” and give way to more of the cushioning effects of the air. The area of the curve labeled 30 corresponds to loads which are cushioned with more compliant gas. The Peak G curve is a plot generated by an impact test such as those described in the Sport Research Review, Physical Tests, published by NIKE, Inc. as a special advertising section, January/February 1990, the contents of which is hereby incorporated by reference.
Another category of prior art concerns air bladders which are injection molded, blow-molded or vacuum-molded such as those disclosed in U.S. Pat. No. 4,670,995 to Huang and U.S. Pat. No. 4,845,861 to Moumdjian, which are incorporated herein by reference. These manufacturing techniques can produce bladders of any desired contour and shape while reducing deep peaks and valleys. The main drawback of these air bladders is in the formation of stiff, vertically aligned columns of elastomeric material which form interior columns and interfere with the cushioning benefits of the air. These bladders are designed to support the weight of the wearer. FIGS. 6 and 7 illustrate cross sections of a prior art bladder 40 which is made by injection molding, blow-molding or vacuum-forming with vertical columns 42 . FIG. 7 illustrates bladder 40 in the loaded condition with load arrows 44 . Since these interior columns are formed or molded in the vertical position, there is significant resistance to compression upon loading which can severely impede the cushioning properties of the air.
In Huang '995 it is taught to form strong vertical columns so that they form a substantially rectilinear cavity in cross section. This is intended to give substantial vertical support to the cushion so that the cushion can substantially support the weight of the wearer with no inflation. Huang '995 also teaches the formation of circular columns using blow-molding. In this prior art method, two symmetrical rod-like protrusions of the same width, shape and length extend from the two opposite mold halves to meet in the middle and thus form a thin web in the center of a circular column. These columns are formed of a wall thickness and dimension sufficient to substantially support the weight of a wearer in the uninflated condition. Further, no means are provided to cause the columns to flex in a predetermined fashion which would reduce fatigue failures. Huang's columns are also prone to fatigue failure due to compression loads which force the columns to buckle and fold unpredictably. Under cyclic compression loads, the buckling can lead to fatigue failure of the columns.
FIG. 8 shows a close-up view of a prior art column similar to those shown in Huang with a thin web in the middle of the column halves formed by a center weld W and a slight draft angle θ to the column halves. While Huang's columns do not appear to have a draft angle, the commercial embodiments of the bladder taught by Huang have shown a draft angle similar to that shown in FIG. 8 .
Included in this prior art category of molded bladders are bladders having inwardly directed indentations as disclosed in U.S. Pat. No. 5,572,804 to Skaja et al, which is hereby incorporated by reference. Skaja et al. disclose a shoe sole component comprising inwardly directed indentations in the top and bottom members of the sole components. Support members or inserts provide some controlled collapse of the material to create areas of cushioning and stability in the component. The inserts are configured to extend into the outwardly open surfaces of the indentations. The indentations can be formed in one or both of the top and bottom members. The indented portions are proximate to one another and can be engaged with one another in a fixed or non-fixed relation. In the Skaja patent, indentations that are generally hemispherical in shape and symmetrical about a central orthogonal axis are taught. The outside shape of the indentation, that is, the shape outlined at the surface of the bladder component is circular. The inserts have the same shape as the indentations. The hemispherical indentations and mating support members or inserts respond to compression by collapsing symmetrically about a center point. While the hemispherical indentations and inserts of Skaja provide for some variation in cushioning characteristics by placement, size and material, there is no provision for biasing or controlling the compression or collapse in a desired direction upon loading. The indentations and the mating inserts contribute to the cushioning response of the bladder which is opposed to the goal of the present invention in which the controlled collapse members are engineered specifically to not interfere with the cushioning response of gas or air.
Yet another prior art category concerns bladders using a corrugated middle film as an internal member as disclosed in U.S. Pat. No. 2,677,906 to Reed which describes an insole of top and bottom sheets connected by lateral connection lines to a corrugated third sheet placed between them. The top and bottom sheets are heat sealed around the perimeter and the middle third sheet is connected to the top and bottom sheets by lateral connection lines which extend across the width of the insole. An insole with a sloping shape is thus produced, however, because only a single middle sheet is used, the contours obtained must be uniform across the width of the insole. By use of the attachment lines, only the height of the insole from front to back may be controlled and no complex-curved, contoured shapes are possible. Another disadvantage of Reed is that because the third, middle sheet is a continuous sheet, all the various chambers are independent of one another and must be inflated individually which is impractical for mass production.
The alternative embodiment disclosed in the Reed patent uses just two sheets with the top sheet folded upon itself and attached to the bottom sheet at selected locations to provide rib portions and parallel pockets. The main disadvantage of this construction is that the ribs are vertically oriented and similar to the columns described in the patents to Huang and Moumdjian, and would resist compression and interfere with and decrease the cushioning benefits of air. As with the first embodiment of Reed, each parallel pocket thus formed must be separately inflated.
A prior bladder and method of construction using flat films is disclosed in U.S. Pat. No. 5,755,001 to Potter et al, which is hereby incorporated by reference. The interior film layers are bonded to the envelope film layers of the bladder which defines a single pressure chamber. The interior film layers act as tensile members which are biased to compress upon loading. The biased construction reduces fatigue failures and resistance to compression. The bladder comprises a single chamber inflated to a single pressure with the tensile member interposed to give the bladder a complex-contoured profile. There is, however, no provision for multiple layers of fluid in the bladder which could be inflated to different pressures providing improved cushioning characteristics and point of purchase feel.
Another well known type of bladder is formed using blow molding techniques such as those discussed in U.S. Pat. No. 5,353,459 to Potter et al, which is hereby incorporated by reference. These bladders are formed by placing a liquefied elastomeric material in a mold having the desired overall shape and configuration of the bladder. The mold has an opening at one location through which pressurized gas is introduced. The pressurized gas forces the liquefied elastomeric material against the inner surfaces of the mold and causes the material to harden in the mold to form a bladder having the preferred shape and configuration.
There exists a need for an air bladder with a suitable tensile member which solves all of the problems listed above: complex-curved, contoured shapes; elimination of deep peaks and valleys; no interference with the cushioning benefits of air alone; and the provision of a reliable bond between tensile member and outer barrier layers. As discussed above, while the prior art has been successful in addressing some of these problems, they each have their disadvantages and fall short of a complete solution.
SUMMARY OF THE INVENTION
The present invention pertains to a bladder with controlled flex connecting members extending between the top and bottom outer layers of bladder. The bladder of the present invention may be incorporated into a sole assembly of an article of footwear to provide cushioning. When pressurized, the outer layers are placed under tension, and the connecting members function as tension members. The bladder provides a reliable bond between the tensile members and the outer barrier layers, and can be constructed to have complex-curved, contoured shapes without interfering with the cushioning properties of air. A complex-contoured shape refers to varying the surface of the bladder in more than one direction. The present invention overcomes the enumerated problems with the prior art while avoiding the design trade-offs associated with the prior art attempts.
In accordance with one aspect of the present invention, a bladder is formed by blow-molding or rotational molding. Both of these methods create internal connection/tensile members which are integral with the outer perimeter layer. Since the outer perimeter and the internal tensile members are formed at the same time and of the same material, bonding problems between layers is eliminated and manufacturing is simplified. By utilizing pins in the blow-molded or rotational mold, tensile column members are formed which can provide a finely contoured shape, but which do not significantly interfere with the cushioning properties of the air, when the bladder contains air or another fluid. It is desirable that the tensile members compress easily under relatively low loads, those exceeding ½ body weight (35 kg) and preferably below 25 kg. In order to prevent fatigue stress on the members, a predetermined flex point is molded into at least a portion of each column. This assures that the members will flex under relatively low loads and that the flexure will occur in a predictable manner, eliminating the prior art problem of fatigue failure in the vertical columns.
To ensure that the tensile members do not interfere with the cushioning properties of air they are configured to be sufficiently flexible to receive compressive loads but are durable even under repeated loading. Broadly, there are two configurations: one in which the tensile member is constructed to collapse upon compressive loading, and one in which the tensile member is constructed to bend or fold like a hinge upon compressive loading in a predetermined location.
In another aspect of the present invention the shape of the flexible tensile column members and the interface at the flex point are manipulated to assist in finely tuning the cushioning properties of the final bladder. Differently shaped cross-sections of columns, e.g. circles, ovals, squares, rectangles, triangles, spirals, half-moons, helices, etc., impart different amounts of resistance to compression and exhibit varying flex properties. Also, the placement, thickness and number of flex points can significantly effect the bending, collapsing, or folding properties of the tensile members. For example, multiple accordion-like pleats molded into the columns impart more flexibility than a single notch or pleat of the same thickness. Additionally, the columns need not be arranged perpendicular to the plane of the bladder surface. By forming the tensile members at various angles, the direction that the tensile member bends or folds can be further controlled.
Yet another aspect of the invention is to vary the lengths of the opposing ends of the tensile columns by utilizing pin or rod-like protrusions of different lengths in the mold, the joint or hinge in the tensile members can be formed off-center. The longer of the two pin or rod-like protrusions forms a column portion of longer length than the shorter pin or rod-like protrusion. This variation in the tensile column's length can be manipulated to direct the flexing of the column under compression.
In another embodiment, the flex point of the tensile column is manipulated by altering the cross-section size of the pin or rod-like protrusions in the mold, whereby the pins or rod-like protrusions in one mold half are larger in cross-section than the ones in the opposing half. This produces a tensile column with one portion larger than the other which allows the smaller portion of the column to telescope or nest into the larger portion upon loading. In such a construction, the larger portion collapses around the smaller portion, rather than acting as a hinge.
In yet another embodiment, spring elements such as elastomeric sheets, may be insert-molded during the blow-molding process to direct the flex properties of the columns. For example, a thin strip of thermoplastic urethane of the same type used to form the main bladder can be located in the mold in such a way that it spans the gap between two of the columns forming pins or rod-like protrusions located in the same half of the mold. The resulting columns formed would be tied together horizontally in the center web portion by the strip. This would prevent columns from flexing easily in any direction except inwardly toward the shared strip.
Another method of manipulating the flex properties of the tensile columns is to vary the draft angle of the pins or rod-like protrusions in the mold which form the columns. A draft angle of zero degrees would produce a column with essentially vertical walls. A draft angle of 5° to 45° is needed in order to cause the column to flex in a predictable manner. In general an increased draft angle in combination with another structural difference such as asymmetry will provide the desired predicted location of collapse. Engineering the location of collapse or flexure in this manner prevents the failures noted with prior art devices. By manipulating some or all of the above factors in various combinations, cross-sectional size, length, shape, hinges, thickness, draft angles and symmetry, it is possible to finely tune the cushioning properties of the bladder and select the most appropriate flex characteristic to prevent fatigue failures and prevent the tensile columns from significantly detracting or interfering with the cushioning benefits and feel of the air.
The present invention provides a bladder with tensile members of complex-curved, contoured shapes without deep peaks and valleys, which facilitates utilization of the cushioning properties of air and which provides a reliable bond between the tensile members and the outer barrier layers of the bladder. The tensile members are columns formed integrally with the barrier layer and are formed with predetermined flex points which are constructed to flex upon compression by collapsing, bending, or rolling so that the tensile members do not substantially interfere with the cushioning effects of the air. The tensile members are less susceptible to fatigue failures when they are not required to perform a significant supportive function and the flex point is constructed for taking repeated compressive loads. This configuration ensures that the tensile members will not compromise the cushioning properties of air.
These and other features and advantages of the invention may be more completely understood from the following detailed description of the preferred embodiment of the invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross section of a prior art bladder using an open-celled foam core as a tensile member.
FIG. 2 is a cross section of the prior art bladder of FIG. 1 shown in the loaded condition.
FIG. 3 is a cross section of a prior art bladder using fabric fibers as tensile members.
FIG. 4 is a cross section of the prior art bladder of FIG. 3 shown in the loaded condition.
FIG. 5 is a Peak G response curve of the prior art bladder of FIG. 3 .
FIG. 6 is a cross section of a prior art bladder using vertical columns as tensile members formed by injection molding, blow-molding or vacuum-forming.
FIG. 7 is a cross section of the prior art bladder of FIG. 6 shown in the loaded condition.
FIG. 8 is a close-up view of a portion of a prior art bladder similar to that shown in FIG. 6, illustrating a vertical column tensile member.
FIG. 9 is a plan view of a bladder in accordance with a preferred embodiment of the present invention.
FIG. 10 is a detailed elevational view of a column tensile member taken along line 10 — 10 of FIG. 9, shown in the unloaded state.
FIG. 11 is a detailed elevational view of a column tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 12 is a detailed elevational view of a column tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 13 is a detailed elevational view of a column tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 14 is a detailed elevational view of a column tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 15 is a detailed elevational view of the tensile member of FIG. 14 shown in a loaded state.
FIG. 16 is a detailed elevational view of a tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 17 a detailed elevational view of tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 18 is a detailed elevational view of a tensile member in accordance with another preferred embodiment of the present invention, shown in an unloaded state.
FIG. 19 is a top plan view of the tensile member illustrated in FIG. 18 .
FIG. 20A is a top plan view of a bladder with pillar shaped controlled flex members in accordance with the present invention.
FIG. 20B is a side elevational view of the bladder of FIG. 20 A.
FIG. 20C is cross section of the bladder taken along line 20 C— 20 C in FIG. 20 A.
FIG. 21A is a top plan view of another bladder with pillar shaped controlled flex members in accordance with the present invention.
FIG. 21B is a side elevational view of the bladder of FIG. 21 A.
FIG. 21C is a cross section of the bladder taken along line 21 C— 21 C of FIG. 21 A.
FIG. 22 is a perspective view of a bladder with drumhead shaped controlled flex members in accordance with the present invention.
FIG. 23 is a top plan view of the bladder of FIG. 22 .
FIG. 24 is a detailed cross section taken through line 24 — 24 of FIG. 23 .
FIG. 25 is a perspective view of a bladder with notched pillar controlled flex members in accordance with the present invention.
FIG. 26 is a top plan view of the bladder of FIG. 25 .
FIG. 27 is a detailed cross section taken through line 27 — 27 of FIG. 26 .
FIG. 28 is a perspective view of a first side of a bladder with chalice shaped controlled flex members in accordance with the present invention.
FIG. 29 is a perspective view of a second side of the bladder of FIG. 28 .
FIG. 30 is a plan view of the second side of the bladder of FIG. 28 .
FIG. 31 is a cross section of the bladder taken through line 31 — 31 of FIG. 30 .
FIG. 32 is a schematic cross section of a chalice shaped controlled flex member shown in an unloaded state.
FIG. 33 is a schematic cross section of the controlled flex member of FIG. 32 shown during compressive loading.
FIG. 34 is a schematic cross section of the controlled flex member of FIGS. 32 and 33 shown in the fully loaded state.
FIG. 35 is a schematic cross section of a chalice shaped controlled flex member of a bladder mounted in a sole assembly shown in an unloaded state.
FIG. 36 is a schematic cross section of a chalice shaped controlled flex member of a bladder mounted in a sole assembly shown in a loaded state.
FIG. 37 is an exploded perspective view of an article of footwear incorporating the bladder of FIG. 28 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In general, the controlled flex connecting members depicted in the figures are schematic representations of variously configured connecting members that can be provided in bladders. When the bladders are sealed and inflated with a fluid, the connecting members are placed under tension and act as tensile members. Since, in a preferred embodiment, the bladder is inflated, the connecting members will be referred to as tensile members; however, it should be understood that when the bladders are in an uninflated state, these members act as controlled flex connecting members. A plurality of one type of these tensile members or a combination of two or more types of tensile members can be provided in a bladder to lend the bladder a desired shape, contour and cushioning characteristics. The tensile members are integral with the top and bottom outer perimeter of the bladder and are created by positioning small diameter pins or forms in correspondence on both of the facing halves of a mold so that tensile members are formed of the barrier material wherever the pins or forms were placed when the bladder is molded. The following detailed description describes a number of possible tensile member structures, and then describes an exemplary number of inflatable bladders having controlled flex tensile members provided therein. The bladders described below embody some exemplary possibilities given the technique of the present invention. It is noted that a multitude of configurations other than those specifically described herein are contemplated to be within the scope of this invention. Bladders with controlled flex tensile members are particularly useful as cushioning devices within soles of footwear.
The preferred method of manufacturing is blow-molding. Blow-molding is a well known technique which is well suited to economically produce large quantities of consistent articles. The use of one, homogenous material provides the articles with inherently good adhesion between the perimeter and interior tensile members due to the fact that they are contiguous with each other. Blow-molding produces clean, cosmetically appealing articles with small inconspicuous seams. Many other prior art bladder manufacturing methods require multiple manufacturing steps, components and materials which makes them difficult and costly to produce. Some prior art methods form conspicuously large seams around their perimeters which can be cosmetically unappealing. Two other known manufacturing methods that can produce good results are rotational molding and injection molding.
Referring now to FIG. 9, a preferred embodiment of a heel bladder 50 is shown having vertical tensile members of varying diameter distributed across the bladder. Heel bladder 50 includes a first, or top, barrier layer 53 and a second, or bottom, barrier layer 55 . The top and bottom barrier layers 53 , 55 are joined to one another along a perimeter 57 to form a sealed chamber. An inlet tube 59 is provided as one way of supplying an inflatent fluid to the sealed chamber. The tensile members of bladder 50 are columnar in shape, with the most slender ones 52 arranged in the rear strike area, medium diameter columns 54 in the central region and larger diameter columns 56 in the forwardmost area. The larger the diameter of the column, the more stiffness it will exhibit upon compressive loading. The area in need of most cushioning in this bladder, the rear strike area, has relatively slender columns to provide a more cushioned response. A detail of a column 56 is shown in FIG. 10 in which controlled flex point 58 is positioned generally in the center of the length of the column. A first portion 61 of column 56 is formed integral with first layer 53 and extends into the sealed chamber of bladder 50 . Similarly, a second portion 63 of column 56 is formed integral with second layer 55 and also extends into the sealed chamber. Such integral formation of first and second column portions is a preferred technique for all tensile members discussed herein. Flex point 58 is formed at the juncture of first and second portions 61 , 63 that make up column 56 , and compressive loading will tend to buckle the column at that predetermined and reinforced flex point.
Flex point 58 provides a predetermined location of flexure for tensile column 56 in response to a compression load. The flexing of column 56 about flex point 58 occurs like a mechanical hinge, so that a hinge area is located about flex point 58 . This selected flex point acts to prevent buckling and bending about random points of the column and the potential for fatigue failure associated with such uncontrolled or undirected flexion.
In general, factors such as wall thickness, column height, and diameter must be taken into account in designing controlled flex tensile members. A shorter column with a thicker wall section and greater diameter will require a greater draft angle to flex under the same load as a taller column with a thinner wall section and a smaller diameter. When one or more of these parameters is adjusted, they yield bladders with different cushioning characteristics due to the differences in the tensile members.
Column 56 illustrates a column with generally equal portions joined together in axial alignment. The portions of a controlled flex member however, can be different in length, diameter, shape and alignment as shown in the following alternative embodiments.
Bladder 50 may be made of a resilient, thermoplastic elastomeric barrier film, such as polyester polyurethane, polyether polyurethane, such as a cast or extruded ester based polyurethane film having a shore “A” hardness of 80-95, e.g., Tetra Plastics TPW-250. Other suitable materials can be used such as those disclosed in U.S. Pat. No. 4,183,156 to Rudy, which is incorporated by reference. Among the numerous thermoplastic urethanes which are particularly useful in forming the film layers are urethanes such as Pellethane™, (a trademarked product of the Dow Chemical Company of Midland, Mich.), Elastollan® (a registered trademark of the BASF Corporation) and ESTANE® (a registered trademark of the B. F. Goodrich Co.), all of which are either ester or ether based and have proven to be particularly useful. Thermoplastic urethanes based on polyesters, polyethers, polycaprolactone and polycarbonate macrogels can also be employed. Further suitable materials could include thermoplastic films containing crystalline material, such as disclosed in U.S. Pat. Nos. 4,936,029 and 5,042,176 to Rudy, which are incorporated by reference; polyurethane including a polyester polyol, such as disclosed in U.S. Pat. No. 6,013,340 to Bonk et al., which is incorporated by reference; or multi-layer film formed of at least one elastomeric thermoplastic material layer and a barrier material layer formed of a copolymer of ethylene and vinyl alcohol, such as disclosed in U.S. Pat. No. 5,952,065 to Mitchell et al., which is incorporated by reference.
Bladder 50 can be sealed to hold air or other fluid at ambient pressure, or can be pressurized with an appropriate fluid, for example, hexafluorethane, sulfur hexafluoroide, nitrogen, air, or other gases such as those disclosed in the aforementioned '156, '029, or '176 patents to Rudy, or the '065 patent to Mitchell et al. If pressurized, the fluid or gas can be placed in bladder 50 through inflation tube 59 in a conventional manner by means of a needle or hollow welding tool. After inflation, the bladder can be sealed at the juncture of the body of bladder 50 and inflation tube 59 , and the remainder of tube 59 can be cut off. Alternatively, tube 59 can be sealed by the hollow welding tool around the inflation point.
Column tensile member 60 is shown in FIG. 11 and depicts another preferred embodiment. The top portion 62 of column 60 is slightly longer than bottom portion 64 , and is also diagonally appointed with respect to the straight vertical bottom portion. A flex point 66 is defined between the top and bottom portions of column 60 . In this particular column, diagonal top portion 62 slants to the right thereby biasing column 60 to bend at flex point 66 to the left, that is, in the direction of arrow 68 , in response to a compressive load. This is accomplished by placing the pin for the top portion of the column at an angle with respect to the vertical in the mold for the bladder.
By this configuration, not only is the point of flexion controlled, but the direction of flexion as well. This type of controlled direction column would be a particularly advantageous tensile member to place at the periphery of a bladder, for example, where the column would be oriented such that flex point 66 would move inward in response to a compressive load. An inward deflection of flex point 66 would ensure that column 60 would not contact or interfere with the side wall of the bladder. A controlled direction column like column 60 would be advantageous to use anywhere that contact with other elements during flexion must be avoided. The length of the diagonal top portion with respect to the vertical bottom portion can be modulated to control the amount of deflection of joint 66 . The relationship of the top and bottom portions can be switched so that the top portion is vertical and the bottom portion is diagonal. Of course, the direction can be altered by varying the direction of the diagonal slant to the diagonal portion, and the draft angle of the diagonal slant can also be adjusted as desired.
As shown in FIG. 12, a tensile member formed of two diagonal portions configured in a sideways “V” shape is also contemplated to be within the scope of the invention. Such a tensile member would flex more easily in response to lower compressive loads. The choice of placement, configuration and relative lengths of the top and bottom portions of a tensile member are all variables and changing these properties results in an array of different cushioning and contour possibilities.
FIG. 13 illustrates another preferred embodiment of a tensile member in which column 70 is depicted. Top portion 72 and bottom portion 74 of column 70 are both diagonally appointed such that their longitudinal axes are aligned. A flex point 76 is defined between the top and bottom portions of column 70 at a midway point. Bottom portion 74 is shown slanted toward the right and top portion 72 also slants toward the right as it extends to the top barrier layer. Column 70 would tend to flex more easily in response to a compressive load than a straight vertical column, and can be used wherever a more sensitive response is needed.
This configuration can be accomplished by placing the pins for the top and bottom portions at appropriate angles with respect to the vertical in the mold for the bladder. As with all of the columns heretofore described, the relative lengths of the top and bottom portions can be altered to further tune the compressive response. Of course depending upon the particular geometry of a bladder, a column which is appointed to slant in the opposite direction may be used when no bias direction is desired. Such a column is depicted in broken lines in FIG. 13 .
Yet another preferred embodiment of a controlled flex tensile member, column 78 , is depicted in FIGS. 14 and 15 in the unloaded and loaded conditions respectively. The flex point is manipulated in this embodiment by altering the diameters of the pins or rod-like protrusions in the mold for the bladder, such that, as seen in FIG. 14, top portion 80 has a greater diameter than bottom portion 82 . A junction 84 is defined between the two. This produces a column having one half wider than the other half so that upon compressive loading, the narrower portion of the column telescopes into the wider portion relative to the junction instead of the junction acting as a simple hinge. FIG. 15 illustrates column 78 in a loaded condition with bottom portion 82 telescoped into top portion 80 with respect to junction 84 . Of course the wider portion may be provided as the bottom portion of the column as well.
In this particular embodiment, the top and bottom portions are formed with a number of differences to enable telescoping flexion: (i) the length of top portion 80 , labeled as α, is longer than the length of bottom portion 82 , labeled as β; (ii) the top draft angle, labeled as δ, is greater than the bottom draft angle, labeled as φ; and (iii) the barrier perimeter thickness is 3 mm in all locations except the portions that make up top portion 80 where the thickness is 2 mm. All of these variations in the parameters enable the bottom portion to telescope into the top portion more easily. As seen in FIG. 15, the thinner wall thickness of top portion 80 enables it to more easily deform upon compression. In addition, the shorter length of bottom portion 82 makes it more resistant to deformation, so it is the portion that remains relatively undeformed and telescopes into a deformable portion of the column. The same can be said of the differences in the draft angles, that an increased draft angle makes that portion of the column more readily collapsible. All of these slight differences add up to customize the column and its behavior upon compressive load, and these parameters can all be adjusted to obtain the desired cushioning characteristics.
FIG. 16 illustrates a variation of the invention in which tensile members are tied together horizontally to further control the direction of flexion of the columns. This preferred embodiment of a tensile member has columns 86 tied together by spring elements 88 such as thin strips of thermoplastic urethane. The strips may be insert-molded during the blow-molding process so that spring element 88 preferably spans the gap between adjacent columns 86 formed by pins or rod-like protrusions located in the same half of the mold for the bladder. The adjacent columns 86 that are tied together horizontally in this manner will tend to flex most easily toward one another and spring element 88 as indicated by arrows 90 . This is because spring element 88 would prevent the columns from flexing away from one another due to the resultant tensioning of the spring element. Of course, spring elements such as element 88 may be used with any tensile member configuration where control of the direction of flexion is desired. This may be particularly advantageous near the periphery of a bladder, or in combination with other tensile members which also tend to flex in a specified direction.
FIGS. 17, 18 , and 19 illustrate further preferred embodiments of the invention in which the draft angles of a column are varied by adjusting the draft angles of the pins or rod-like protrusions in the mold for the bladder when forming the columns. In general, a draft angle of between 5° and 45° is needed in order to cause a column to flex in a predictable manner. The draft angle at the base of the pins or rod-like protrusions which form the columns can also effect the flex properties. The base of the pins or rod-like protrusions form the base of the tensile columns, and is the portion closest to the top and bottom surfaces of barrier layer of the bladder. Therefore, increasing or decreasing the draft angle at the base of the pins increases or decreases the wall thickness at the base of the column, thus effecting where and under what load the column will flex. The preferred draft angle range for the base of a column is 5° to 20°.
Specifically, FIG. 17 illustrates a preferred embodiment of the present invention in which a column 92 is depicted in an unloaded condition. The draft angle at the base of the column is labeled σ, and the draft angle of the mid-portion of the column is labeled ψ. In this particular embodiment angle a is preferably 7° and angle ψ is preferably 5°. The “elbows” formed by draft angles σ and ψ would tend to flex in response to a compressive load thereby controlling the placement of the flexion and preventing unexpected buckling or bending elsewhere along the column.
FIGS. 18 and 19 illustrate another preferred embodiment of the present invention in which a column 94 is formed with draft angles which tend to direct flexion in a specific direction. The base of column 94 is circular, as seen in FIG. 19 . Base draft angles σ are provided on both sides of the column, but mid-portion draft angles ψ are only provided on one side of the column. In response to a compressive load, column 94 would tend to flex in the direction of arrows 96 since the “elbows” formed by mid-portion angles ψ would tend to flex more easily. In this particular embodiment angle σ is preferably 7° and angle ψ is preferably 5°. Thus, the direction of flexion as well as the location is controlled.
In the manner described herein, it is possible to finely tune the cushioning properties of the air bladder, and it is also possible to tune the flex properties of each individual column to match the impact requirements and anticipated sheer loads for a specific portion of the air bladder. Different athletic activities would benefit from air bladders designed to flex and sheer in manners that enhance the natural movements of the athlete performing the activity. For example, less flexible tensile members on the medial side of an air bladder used in a running shoe would provide increased resistance to compression and thus contribute to a reduced rate of pronation. Another example would be for activities that require quick cutting movements such as basketball and tennis. It may be beneficial to have the tensile members exhibit increased flexibility when loaded during a lateral cutting motion if it is shown that the tensile members experience fatigue failures due to the high loading conditions in these portions of the air bladder. Of course, other means would then need to be employed to increase the stability in these areas.
FIGS. 20A-20C illustrate a heel bladder 100 having tensile members 102 which are formed in the side peripheral areas of greatest height, and other tensile members 104 , 106 in the transition areas and central area. As can be seen in FIGS. 20B and 20C, bladder 100 forms a tapered well for a heel with raised side and rear peripheral edges. The tallest areas have a height labeled l 1 in FIG. 20 C and the lowest areas such as the central region have a height labeled l 2. Tensile members formed in the raised edges, columns 102 , and in the transition areas, columns 104 , in which the top barrier layer slopes downward into the lower central region, are taller than the tensile members, columns 106 . The sloping and contouring are best seen in FIGS. 20B and 20C. Tensile member 102 of total length l 1 is shown in cross-section in FIG. 19C, and it can be seen that the top and bottom portions are of unequal length. The shortest columns 106 will be of length l 2 . All of the columns of bladder 100 are of equal diameter, and the combination of these columns lend bladder 100 its contoured shape. The contoured shape of bladder 100 allows it to be inserted into a sole assembly of a shoe without encasing it in foam. Eliminating as much foam as possible from the sole assembly eliminates interference with the cushioning properties of air.
FIGS. 21A-21C illustrate another embodiment of a contoured, tapered heel bladder 110 having formed therein partial columns or pillars 112 . Then, immediately inside of the partial pillars are large pillars 114 which are of relatively large diameter extending along the sides, and intermediate pillars 116 which are of a smaller diameter in the rear portion of the bladder. The central portion of bladder 110 has formed therein a multitude of thin pillars 118 which are least resistant to compression. Since bladder 110 is tapered, partial pillars 112 are placed in the periphery and therefore are the tallest. Large pillars 114 and intermediate pillars 116 are in the transition area where the top of the bladder slopes downward. Thin pillars 118 are in the central area and are the shortest. Using larger diameter pillars in the peripheral areas provides “stiffer” cushioning characteristics to the edges.
FIGS. 22-24 illustrate another preferred embodiment in which a bladder 120 is provided with drumhead tensile members or pillars 122 . Each drumhead pillar 122 comprises a larger diameter portion 124 and a smaller diameter portion 126 in vertical and axial alignment with one another and joined at interface or juncture 128 . These pillars are called drumhead pillars due to the similarity in shape of larger diameter portion 124 to a drum. In this particular bladder, the pillars are arranged in alternating fashion so that adjacent pillars are in inverted relation to one another. From either side of the bladder, larger diameter portions 124 alternate with smaller diameter portions 126 . Smaller diameter portion 126 is designed to collapse into larger diameter portion 124 upon full compressive loading. As can be seen in FIG. 24, larger diameter portions 124 are designed to have a curvature onto which is joined smaller diameter portions 126 . This interface 128 allows for the smaller diameter portions to flex by rolling slightly with respect to the drumhead or larger diameter portions when the bladder is compressed slightly. To enable the smaller diameter portion of the pillar to collapse into the drumhead, compressive loading must be sufficient to overcome the curvature of the drumhead. As a result, this type of controlled flex tensile member provides a relatively stiff response to compressive loading.
FIGS. 25-27 illustrate another preferred embodiment in which a bladder 130 is provided with notched tensile members or pillars 132 . Each notched pillar 132 comprises opposed portions having trapezoidal cross sections 134 and 136 joined at a junction 138 , with notches formed at the junctures of the sides of the trapezoid. The junction 138 has a minor axis, labeled α in FIG. 26, and a major axis, labeled β. The surface area of the junction will be a factor in determining the controlled flex direction of the pillar. Unless the surface area is a perfect square, a notched pillar will tend to flex in a direction parallel to the minor axis α. Of course since the direction is flexion is preferably controlled, the surface area of the juncture of notched pillar portions should generally be rectangular to take advantage of this material property. As seen in FIG. 27, notched pillars 132 will tend to flex in the direction of arrow 139 upon compressive loading of the bladder. Notched pillars provide a relatively stiff response to a compressive load similar to drumhead pillars.
FIGS. 28-36 illustrate yet another preferred embodiment in which a bladder 140 is provided with collapsible tensile members 142 . These tensile members, in cross section, have a shape that is reminiscent of a chalice shape, and are referred to as chalice shaped tensile members. Each chalice shaped tensile member is comprised of a cup portion 144 opening to one side of the bladder, and a base portion 146 opening to the opposite side of the bladder. FIGS. 28 and 29 illustrate the two sides of bladder 140 , FIG. 28 showing the side with the bases up, and FIG. 29 showing the side with the cups up. As best seen in FIG. 30, junctions 148 between cup portions 144 and base portions 146 are circular. The cross sections of FIGS. 31-36 are schematic and do not fully illustrate that interface which actually has a slight depression in the underside of the cup portion where the base portion is attached. This ensures that upon compressive loading, there is no rolling of the portions with respect to one another, but that tensile member 142 collapses as it is designed to collapse.
Tensile members 142 are designed to collapse into one another by base portion 146 collapsing into the bottom of cup portion 144 . FIG. 31 is shown with the cup portions facing upward to illustrate the shapes of the tensile members. In a sole assembly of a shoe, however, the cup portion would generally be facing downward toward the ground or ground engaging element. FIGS. 32-34 illustrate schematically a tensile member 142 in the unloaded state, during load and upon full compressive load respectively. Base portion 146 pushes into cup portion 144 providing predetermined collapse of the tensile member. In general, tensile members 142 provide a relatively soft response to a compressive load and are suitable for a strike area.
In an alternative configuration, a bladder 140 ′ with tensile members 142 ′ can be used with an outsole with openings that allow the collapsed underside of the tensile members to extend downward, even beyond the outsole and engage the ground. FIGS. 35 and 36 illustrate such a configuration schematically in the unloaded and fully loaded conditions respectively. Outsole 150 is attached to bladder 140 ′ and is adapted to engage the ground. Outsole 150 has perforations or other openings so that cup portion 144 ′ opens to the ground. When bladder 140 ′ is compressively loaded, base portion 146 ′ collapses into cup portion 144 ′, and the point of juncture 148 ′ extends beyond the outsole 150 and engages the ground. This configuration may be especially suitable for enhancing the traction of footwear designed for soft surfaces such as grass, clay or dirt. Also, since it would take a full compressive load for the point to extend through the outsole and contact the ground, this type of tensile member and outsole combination is likely most useful for strike areas of the foot such as the heel area or under the ball of the foot. In other words, areas where a fill compressive load occurs frequently.
A bladder 140 is illustrated in FIG. 37 as part of a midsole assembly for a shoe S. The shoe comprises an upper U, an insole I, a midsole assembly M, and an outsole O. Bladder 140 can be incorporated into midsole 175 by any conventional technique such as foam encapsulation or placement in a cut-out portion of a foam midsole. A suitable foam encapsulation technique is disclosed in U.S. Pat. No. 4,219,945 to Rudy, hereby incorporated by reference.
In the embodiments disclosed herein, the juncture between the two portions making up the tensile member is formed during the molding process for the bladder so that there would be actual fusion of material at the juncture. The two portions of the tensile members are drawn separately and shown with a boundary for illustrative purposes.
From the foregoing detailed description, it will be evident that there are a number of changes, adaptations, and modifications of the present invention which come within the province of those skilled in the art. However, it is intended that all such variations not departing from the spirit of the invention be considered as within the scope thereof as limited solely by the claims appended hereto. | A bladder for a sole assembly of a shoe with three dimensional controlled flex connecting/tensile members extending between the top and bottom outer layers of bladder. The connecting/tensile members are formed during molding of the bladder and comprise top and bottom portions that come together at a juncture. Since the outer perimeter and the internal connecting/tensile members are formed at the same time and of the same material, bonding problems between layers is eliminated and manufacturing is simplified. The connecting/tensile members are formed with a predetermined flex point in at least a portion of each member to reduce random fatigue stress concentrations. Broadly, there are two configurations: one in which the tensile member is constructed to collapse upon compressive loading, and one in which the tensile member is constructed to bend or fold upon compressive loading in a predetermined location. The shape, relative size, length and barrier material thickness are manipulated to assist in finely tuning the cushioning properties of the final bladder. | 0 |
FIELD OF THE INVENTION
This invention relates to thermal dye transfer printing, and in particular to a novel thermal dye transfer receptor sheet for such printing using a modified polyvinyl chloride resin.
BACKGROUND OF THE INVENTION
In thermal dye transfer printing, an image is formed on a receptor sheet by selectively transferring a dye to a receptor sheet from a dye donor sheet placed in momentary contact with the receptor sheet. Material to be transferred from the dye donor sheet is directed by a thermal printhead, which consists of small electrically heated elements (print heads). These elements transfer image-forming material from the dye donor sheet to areas of the dye receptor sheet in an image-wise manner. Thermal dye transfer systems have advantages over other thermal transfer systems, such as chemical reaction systems, thermal mass transfer systems, and sublimation dye transfer systems. In general thermal dye transfer systems offer greater control of gray scale than these other systems, but they have problems as well. One problem is release of the dye donor and receptor sheets during printing. This has been addressed often by the addition of dye-permeable release coatings applied to the surface of the dye receptor layer. Additionally, materials are required for use in the receptor layer having suitable dye permeability, mordanting properties, adhesion to the substrate, and long term light and thermal stability.
Polyvinyl chloride derivatives and copolymers have been heavily used in thermal dye transfer receptor sheets, because of their properties in these areas. For example, U.S. Pat. No. 4,853,365 discloses that chlorinated polyvinyl chloride, used as a dye receptor, has good dye solubility and high dye receptivity. Similarly, vinyl chloride/vinyl acetate copolymers have also been used in thermal dye transfer receptor sheets as described in Japanese published application nos. 29,391 (1990) and 39,995 (1990). Japanese published application no. 160,681 (1989) discloses dye acceptance layers comprising polyvinyl chloride-polyvinyl alcohol copolymers, and Japanese published application nos. 43,092 (1990), 95,891 (1990) and 108,591 (1990) discloses dye image receiving layers comprising a hydroxy modified polyvinyl chloride resin and an isocyanate compound. U.S. Pat. No. 4,897,377 discloses a thermal transfer printing receiver sheet comprising a supporting substrate coated on at least one surface with an amorphous polyester resin. Published European patent application 133,012 (1985) discloses a heat transferable sheet having a substrate and an image-receiving layer thereon comprising a resin having an ester, urethane, amide, urea, or highly polar linkage, and a dye-releasing agent, such as a silicone oil, being present either in the image-receiving layer or as a release layer on at least part of the image receiving layer. Published European patent application 133,011 (1985) discloses a heat transferable sheet based on imaging layer materials comprising first and second regions respectively comprising (a) a synthetic resin having a glass transition temperature of from -100° to 20° C., and having a polar group, and (b) a synthetic resin having a glass transition temperature of 40° C. or above.
Generally, polyvinyl chloride based polymers are photolytically unstable, decomposing to form hydrogen chloride, which in turn degrades the image-forming dyes. This has made necessary the extensive use of UV stabilizers and compounds that neutralize hydrogen chloride. The dye transfer receptor sheets of this invention employ a modified polyvinyl chloride resin that has much higher light stability than materials previously used, while retaining the desirable properties associated with polyvinyl chloride based resins.
What the background art does not disclose but this invention teaches is that epoxy/hydroxy/sulfonate functionalized polyvinyl chloride resins are particularly useful components in the construction of thermal dye transfer receptor sheets having improved dye image stability.
SUMMARY OF THE INVENTION
It is an aspect of the invention to provide a thermal dye transfer receptor element for thermal dye transfer in intimate contact with a dye donor sheet, the receptor comprising a supporting substrate having on at least one surface thereof a dye receptive receiving layer comprising a vinyl chloride containing copolymer which has a glass transition temperature between about 59° and 65° C., a weight average molecular weight between about 30,000 and about 50,000 g/mol, a hydroxyl equivalent weight between about 500 or 1000 and about 7000 g/mol, a sulfonate equivalent weight between about 11,000 and about 19,200 g/mol, and an epoxy equivalent weight between about 500 and about 7000 g/mol. The donor sheet comprises a substrate with a dye donor layer coated thereon, and the dye receptive receiving layer is in intimate contact with said dye donor layer.
It is another aspect of this invention to provide thermal dye transfer receptor sheets as described above wherein a polysiloxane release layer is coated on the dye receptive receiving layer.
The thermal dye transfer receptor sheets of the invention have good dye receptivity and excellent dye-image thermal stability properties.
DETAILED DESCRIPTION OF THE INVENTION
The thermal dye transfer receptor sheets of the invention comprise a supporting substrate having a dye receptive layer on at least one surface. The dye receptive layer is optionally coated with a polysiloxane release layer.
Problems with presently used dye receiving layer systems include poor shelf-life of the dye in the donor sheet, blooming of the dye (i.e., movement out of the resin system), and bleeding of the dye (i.e., transfer of dye from the dye receiving layer onto another material in contact with it). In addition, polyvinyl chloride based resins are prone to shelf-life problems since they decompose to form hydrogen chloride on exposure to light.
Accordingly, in the present invention it has been found that a vinyl chloride containing copolymer which has a glass transition temperature between about 59° and 65° C., a weight average molecular weight between about 30,000 and about 50,000 g/mol, a hydroxyl equivalent weight between about 1890 and about 3400 g/mol, a sulfonate equivalent weight between about 11,000 and about 19,200 g/mol, and an epoxy equivalent weight between about 500 and about 7000 g/mol provide good dye receptivity while substantially increasing shelf-life of the dye image. Copolymers useful in this invention are commercially available from Nippon Zeon Co., (Tokyo, Japan) under the trade names MR-110, MR-113, and MR-120. Alternatively, they may be prepared according to the methods described in U.S. Pat. Nos. 4,707,411, 4,851,465, or 4,900,631 which are herein incorporated by reference.
Suitable comonomers for polymerization with polyvinyl chloride are likewise included in the above cited patents. They include but are not limited to epoxy containing copolymerizable monomers such as (meth)acrylic and vinyl ether monomers such as glycidyl methacrylate, glycidyl acrylate, glycidyl vinyl ether, etc. Sulfonated copolymerizable monomers include but are not limited to (meth)acrylic monomers such as ethyl (meth)acrylate-2-sulfonate, vinyl sulfonic acid, allylsulfonic acid, 3-allyloxy-2-hydroxypropanesulfonic acid, styrene sulfonic acid and metal and ammonium salts of these compounds. Hydroxyl group containing copolymerizable monomers include but are not limited to hydroxylated (meth)acrylates such as 2-hydroxyethyl (meth)acrylate 2-hydroxybutyl (meth)acrylate; alkanol esters of unsaturated dicarboxylic acid such as mono-2-hydroxypropyl maleate and di-2-hydroxypropyl maleate and mono-2-hydroxybutyl itaconate, etc.; olefinic alcohols such as 3-buten-1-ol, 5-hexen-1-ol, 4-penten-1-ol, etc. Additional comonomers that may be copolymerized in minor amounts not to exceed 5% by weight in total include alkyl (meth)acrylate esters such as methyl (meth)acrylate, propyl (meth)acrylate, and the like; and vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate and the like.
The dye image receptor layer must be compatible as a coating with a number of resins, since most commercially available dye donor sheets are resin based. Since different manufacturers generally use different resin formulations in their donor sheets, the dye receiving layer should have an affinity for several different resins. Because the transfer of dye from the dye donor sheet to the dye receptor sheet is essentially a contact process, it is important that there be intimate contact (e.g., no air gaps or folds) between the dye donor sheet and the dye receptor sheet at the instant of heating to effect imaging.
The proper selection of softening temperature (e.g. glass transition temperature, Tg) of the dye receiving layer is important in the preparation of the thermal dye transfer receptor sheet. Preferably the dye receiving layer should soften at or slightly below the temperatures employed to transfer dye from the dye donor sheet. The softening point, however, must not allow the resin to become distorted, stretched, wrinkled, etc. In addition, the dye receptor sheet is preferably non-tacky and capable of being fed reliably into a thermal printer, and is of sufficient durability that it will remain useful after handling, feeding, and removal from processing.
The dye receptor sheet may be prepared by introducing the various components for making the dye receiving layer into suitable solvents (e.g., tetrahydrofuran (THF), methyl ethyl ketone (MEK), and mixtures thereof, MEK/toluene blends mixing the resulting solutions at room temperature (for example), then coating the resulting mixture onto the substrate and drying the resultant coating, preferably at elevated temperatures. Suitable coating techniques include knife coating, roll coating, curtain coating, spin coating, extrusion die coating, gravure coating, etc. The dye receiving layer is preferably free of any observable colorant (e.g., an optical density of less than 0.2, preferably less than 0.1 absorbance units). The thickness of the dye receiving layer is from about 0.001 mm to about 0.1 mm, and preferably 0.005 mm to 0.010 mm.
Materials that have been found useful for forming the dye receiving layer include sulfonated hydroxy epoxy functional vinyl chloride copolymers as described above, and in another embodiment blends of sulfonated hydroxy epoxy functional vinyl chloride copolymers with other polymers. The limiting factors to the resins chosen for the blend vary only to the extent of compounding necessary to achieve the property desired. Preferred blendable additives include, but are not limited to polyvinyl chloride, acrylonitrile, styrene-acrylonitrile copolymers, polyesters (especially bisphenol A fumaric acid polyester), acrylate and methacrylate polymers (especially polymethyl methacrylate), epoxy resins, and polyvinyl pyrrolidone. When an additional polymer, copolymer, or resin is used it is usually added in an amount of 75 percent by weight or less of the resinous composition of the dye receiving layer, preferably in the amount of 30 to 75 percent by weight for non-release polymers, or 0.01 to 15% for release polymers.
Release polymers are characterized by low surface energy and include silicone and fluorinated polymers. Non-limiting examples of release polymers are poly dimethyl siloxanes, perfluorinated polyethers, etc.
Suitable substrate materials may be any flexible material to which an image receptive layer may be adhered. Suitable substrates may be smooth or rough, transparent, opaque, and continuous or sheetlike. They may be porous or essentially non-porous. Preferred backings are white-filled or transparent polyethylene terephthalate or opaque paper. Non-limiting examples of materials that are suitable for use as a substrate include polyesters, especially polyethylene terephthalate, polyethylene naphthalate, polysulfones, polystyrenes, polycarbonates, polyimides, polyamides, cellulose esters, such as cellulose acetate and cellulose butyrate, polyvinyl chlorides and derivatives, polyethylenes, polypropylenes, etc. The substrate may also be reflective such as in baryta-coated paper, an ivory paper, a condenser paper, or synthetic paper. The substrate generally has a thickness of 0.05 to 5 mm, preferably 0.05 mm to 1 mm.
By "non-porous" in the description of the invention it is meant that ink, paints and other liquid coloring media will not readily flow through the substrate (e.g., less than 0.05 ml per second at 7 torr applied vacuum, preferably less than 0.02 ml per second at 7 torr applied vacuum). The lack of significant porosity prevents absorption of the heated receptor layer into the substrate.
The thermal dye transfer receptor layers of the invention are used in combination with a dye donor sheet wherein a dye image is transferred from the dye donor sheet to the receptor sheet by the application of heat. The dye donor layer is placed in contact with the dye receiving layer of the receptor sheet and selectively heated according to a pattern of information signals whereby the dyes are transferred from the donor sheet to the receptor sheet. A pattern is formed thereon in a shape and density according to the intensity of heat applied to the donor sheet. The heating source may be an electrical resistive element, a laser (preferably an infrared laser diode), an infrared flash, a heated pen, or the like. The quality of the resulting dye image can be improved by readily adjusting the size of the heat source that is used to supply the heat energy, the contact place of the dye donor sheet and the dye receptor sheet, and the heat energy. The applied heat energy is controlled to give light and dark gradation of the image and for the efficient diffusion of the dye from the donor sheet to ensure continuous gradation of the image as in a photograph. Thus, by using in combination with a dye donor sheet, the dye receptor sheet of the invention can be utilized in the print preparation of a photograph by printing, facsimile, or magnetic recording systems wherein various printers of thermal printing systems are used, or print preparation for a television picture, or cathode ray tube picture by operation of a computer, or a graphic pattern or fixed image for suitable means such as a Video camera, and in the production of progressive patterns from an original by an electronic scanner that is used in photomechanical processes of printing.
Suitable thermal dye transfer donor sheets for use in the invention are well known in the thermal imaging art. Some examples are described in U.S. Pat. No. 4,853,365 which is hereby incorporated by reference.
Other additives and modifying agents that may be added to the dye receiving layer include UV stabilizers, heat stabilizers, suitable plasticizers, surfactants, release agents, etc., used in the dye receptor sheet of the present invention.
In a preferred embodiment, the dye receiving layer of the invention is overcoated with a release layer. The release layer must be permeable to the dyes used under normal transfer conditions in order for dye to be transferred to the receiving layer. Release materials suitable for this layer may be fluorinated polymers such as polytetrafluoroethylene, and vinylidene fluoride/vinylidene chloride copolymers, and the like, as well as dialkylsiloxane based polymers such as polydimethylsiloxane, polyvinyl butyral/siloxane copolymers such as Dai-Allomer™ SP-711 (manufactured by Daicolor Pope, Inc., Rock Hill, S.C.) and urea-polysiloxane polymers.
Alternatively, improved release properties may be achieved by addition of a silicone or mineral oil to the dye receiving layer during formulation.
EXAMPLES
The term "PVC" refers to polyvinyl chloride.
The term "PET" refers to polyethylene terephthalate.
The term "Meyer bar" refers to a wire wound rod such as that sold by R & D Specialties, Webster, N.Y.
The following dyes are used in the examples that follow: ##STR1##
Butyl Magenta may be prepared as described in U.S. Pat. No. 4,977,134 (Smith et al.); HSR-31 was purchased from Mitsubishi Kasel Corp., Tokyo, Japan; AQ-1 was purchased from Alfred Bader Chemical (Aldrich Chemical Co., Milwaukee, WI); Foron Brilliant Blue was obtained from Sandoz Chemicals, Charlotte, NC; Heptyl Cyan and Octyl Cyan were prepared according to the procedures described in Japanese published application 60-172,591.
EXAMPLE 1
This example describes the preparation of a dye receptor layer containing a multi-functionalized polyvinyl chloride and its use.
A solution containing 10 wt % MR-120 (a vinyl chloride copolymer, hydroxy equivalent weight 1890 g/mol, sulfonate equivalent weight 19200 g/mol, epoxy equivalent weight 5400 g/mol, T g =65° C., M w ≈30,000 obtained from Nippon Zeon Co., Tokyo, Japan) and 1.5 wt % Fluorad™ FC-431 (a fluorinated surfactant available from 3M Company, St. Paul, MN) in MEK was knife coated onto 4-mil (0.1 mm) PET film at a 4 mil (0.1 mm) wet film thickness. The coated film was then dried.
A gravure coated magenta colored dye donor sheet composed of:
______________________________________AQ-1 (1-amino-2-methoxy-4-(4-methyl- 3.61 wt %benzenesulfonamido)anthraquinone)HSR-31 32.49 wt %Geon ® 178 37.7 wt %(polyvinyl chloride, B.F. Goodrich Co.,Cleveland, OH)Goodyear Vitel ™ PE-200 2.7 wt %(Goodyear Chemicals Co., Akron, OH)RD-1203 15.0 wt %(a 60/40 blend of polyoctadecyl acrylateand polyacrylic acid, 3M Company,St. Paul, MN)Troysol ™ CD 1 8.5 wt %(CAS registry no.: 64742-88-7, purchasedfrom Troy Chemical, Newark, NJ)______________________________________
was coated onto 5.7 micron Teijin F22G polyester film (Teijin Ltd., Tokyo, Japan) at a dry coating weight of 0.7 g/m 2 .
This donor sheet was used to transfer the dye to the receptor using a thermal printer. The printer used a Kyocera raised glaze thin film thermal print head (Kyocera Corp., Kyoto, Japan) with 8 dots per mm and 0.3 watts per dot. In normal imaging, the electrical energy varies from 0 to 16 joules/cm 2 , which corresponds to head voltages from 0 to 14 volts with a 23 msec burn time.
The dye donor and receptor sheets were assembled and imaged with the thermal print head with a burn time of 23 msec at 16.6 volts, and a heating profile (70-255 msec on/0-150 msec off) with 8 step gradations. The resultant transferred image density (i.e., reflectance optical density) at the 7 l th was 1.53 as measured by a MacBeth TR527 densitometer (Status A filter).
The transferred images were then tested for ultraviolet light (UV) stability in an accelerated UV test device, UVcon™ (Atlas Electric Devices Co., Chicago, IL) equipped with eight 40 watt UVA-351 fluorescent lamps at 351 nm and 50° C. for 121 hours. The loss in image density was 48%.
COMPARATIVE EXAMPLE A
A receptor sheet comprising NCAR® VYNS-3 (a vinyl chloride/vinyl acetate copolymer, 9:1 by weight, M n =44,000, Union Carbide, Danbury, CT), in place of MR-120, coated onto PET film was prepared as in Example 1. After transfer of the donor sheet dyes, as described in Example 1, the image density at the 7 l th step was 1.50. Following UV exposure as described in Example 1, the resultant loss in image density was 82%.
COMPARATIVE EXAMPLE B
A receptor sheet comprising UCAR® VAGH (a vinyl chloride/vinyl acetate/vinyl alcohol copolymer, 90:4:6 by weight, M n =27,000, in place of MR-120, coated onto PET film was prepared as in Example 1.
After transfer of the donor sheet dyes, as described in Example 1, the image density at the 7 th step was 1.57. Following UV exposure as described in Example 1, the resultant loss in image density was 72%.
Example 1 and comparative Examples A and B demonstrate that the claimed receiver layer has good receptivity and improved UV stability.
EXAMPLE 2
This example describes the preparation and comparison of dye receptor sheets employing different PET substrates.
The first PET substrate (Substrate A) was a heat treated 4 mil (0.1 mm) PET clear film (describe), while the second PET substrate (Substrate B) was 4 mil PET film primed on one side with poly(vinylidene chloride).
A receptor layer solution was coated onto Substrate A and the unprimed side of Substrate B using a #12 Meyer bar to give a 0.152 mm wet thickness film.
The receptor layer solution was composed of:
______________________________________2.89 wt % Atlac ™ 382ES (a trademarked bis- phenol A fumarate polyester obtained from ICI America, Wilmington, DE)2.33 wt % Temprite ™ 678 × 512 (a trade- marked 62.5% chlorinated PVC obtained from B.F. Goodrich, Cleveland, OH)0.47 wt % Epon ™ 1002 (a trademarked epoxy resin obtained from Shell Chemical, Houston, TX)0.47 wt % Vitel ™ PE200 (a trademarked polyester obtained from Goodyear, Akron, OH)0.58 wt % Fluorad ™ FC 430 (a trademarked fluorocarbon surfactant obtained from 3M Company, St. Paul, MN)0.17 wt % Tinuvin ™ 328 (a UV stabilizer obtained from Ciba-Geigy, Ardsley, NY)0.29 wt % Uvinul ™ N539 (a UV stabilizer obtained from BASF, New York, NY)0.58 wt % Therm-Check ® 1237 (a cadmium containing heat stabilizer obtained from Ferro Chemical Division, Bedford, OH)0.93 wt % 4-dodecyloxy-2-hydroxybenzophenone (obtained from Eastman Chemical)25.17 wt % methyl ethyl ketone66.12 wt % tetrahydrofuran______________________________________
Dye receptivity was tested by transferring from cyan and magenta donor sheets through a thermal printer having a Kyocera raised glaze thin film print head with 8 dots per mm at 0.3 watts per dot.
The magenta donor sheet was prepared as in Example 1 using the following magenta donor layer formulation:
______________________________________Butyl Magenta 8.42 wt %HSR-31 33.68 wt %Geon ® 178 39.4 wt %Vitel ™ PE 200 2.8 wt %RD-1203 15.7 wt %______________________________________
and coated to a dry thickness of 0.7 g/m 2 onto 5.7 micron Teijin F22G polyester film.
The cyan donor sheet was prepared as in Example 1 using the following cyan donor layer formulation:
______________________________________Heptyl Cyan 17.8 wt %Octyl Cyan 17.8 wt %Foron Brilliant Blue 17.8 wt %Geon ® 178 35.59 wt %Vitel ™ PE 200 3.56 wt %RD-1203 7.45 wt %______________________________________
and coated to a dry thickness of 0.7 g/m 2 onto 5.7 micron Teijin F22G polyester film.
Dye donor and receptor sheets were assembled and imaged with the thermal print head with a burn time of 23 msec at 16.5 volt and a burn profile of 70-255 msec on and 0-150 msec off. Eight levels of gradation were used. The resultant transferred image density (ROD) was measured with a MacBeth TR527 densitometer and tested for UV stability in a UVcon (Atlas Electric Devices Co., Chicago, IL) equipped with eight 40 watt UVA-351 fluorescent lamps at 351 nm and 50° C. for 46.5 hours. The results for levels 6 and 8 are summarized in Table 1.
TABLE 1______________________________________ Initial Image Density % Loss in RODDonor Substrate Substrate Substrate SubstrateUsed Level A B A B______________________________________Magenta 6 1.34 1.29 41.8 75.2 8 1.44 1.40 47.9 78.6Cyan 6 2.13 2.11 18.8 25.6 8 2.33 2.22 5.2 6.8______________________________________
Table 1 demonstrates that dye receptivities of the claimed receptors are comparable in terms of image density. Better UV stability was observed on the heat-treated polyester substrate (Substrate A).
EXAMPLE 3
This example describes the preparation and performance of dye receptors containing MR-120 and UV absorbers. Several commercially available UV absorbers were incorporated with multifunctional PVC (i.e., MR-120) into a dye receptive layer. A control coating solution containing 9.8 wt % MR-120 resin and 1.2 wt % Fluorad™ FC-430 in MEK was coated on Substrate A with a #12 Meyer bar at a wet film thickness of 5 mils. After drying, the receptor was tested for dye receptivity and image UV stability as described in Example 2. The magenta donor sheet contained HSR-31/Butyl Magenta at a 4 to 1 ratio. Similar receptor solutions were prepared with addition of UV absorbers in the amount of 3.34 g UV absorber per 59.9 g of MR-120. The results are shown in Table 2.
TABLE 2______________________________________ Initial Image % Loss in ROD Density After at 14 volts, 90 hr UVStabilizer ROD Exposure______________________________________None 0.86 55.9Tinuvin ™ 144 0.89 70.8(a hindered amine light stabilizer)Uvinul ™ 490 0.91 59.3(a mixture of 2-hydroxy-4-methoxybenzophenone and othertetra-substituted benzophenones)Uvinul ™ N-539 1.03 56.3(2-ethylhexyl 2-cyano-3,3-diphenylacrylate)Ferro ® UV-Chek ® AM300 0.98 41.8(2-hydroxy-4-n-octyloxybenzo-phenone)Uvinul ™ 400 1.09 48.6(2,4-dihydroxybenzophenone)Tinuvin ™ 622LD 1.10 74.6(a hindered amine light stabilizer)Uvinul ™ M-40 1.11 61.3(2-hydroxy-4-methoxybenzo-phenone)Uvinul ™ N-35 1.10 54.6(Ethyl 2-cyano-3,3-diphenyl-acrylate)Tinuvin 328 1.03 71.82-(3,4-di-t-amyl-2-hydroxy-phenyl)-2H-1,2,3-benzotriazole)______________________________________
EXAMPLE 4
This example describes the preparation of two different dye receptors employing other multi-functionalized polyvinyl chloride copolymers.
The first receptor was prepared by coating a solution of 10 wt % MR-110 (a vinyl chloride containing copolymer; hydroxy equivalent weight 3400 g/mol, sulfonate equivalent weight 13000 g/mol, epoxy equivalent weight 1600 g/mol, T g =59° C., M w ≈43,400 obtained from Nippon Zeon Co., Tokyo, Japan) and 1.5 wt % Fluorad™ FC-431 (a fluorochemical surfactant obtained from 3M Company, St. Paul, MN) in methyl ethyl ketone onto a 4 mil (0.1 mm) heat stabilized polyethylene terephthalate (PET) film with a wire wound bar at 3 mil (0.075 mm) gap. The coated film was then dried.
The second receptor was prepared in the same fashion except that MR-113 (a vinyl chloride copolymer; hydroxy equivalent weight 2400 g/mol, sulfonate equivalent weight 11000 g/mol, epoxy equivalent weight 2100 g/mol, T g =62° C., M w ≈50,200 obtained from Nippon Zeon Co., Tokyo, Japan) was used in place of MR-110.
A gravure coated magenta-colored dye donor sheet composed of HSR-31/Butyl Magenta dyes in a 4:1 ratio was used to transfer the dyes to the receptors through a thermal printer. The printer used a Kyocera raised glaze thin film thermal print head with 8 dots per mm and 0.3 watts per dot. In normal imaging, the electrical energy varies from 0 to 16 joules/cm 2 , which corresponds to head voltages from 0 to 14 volts with a 23 msec burn time.
The dye donor and receptor sheets were assembled and imaged with the thermal print head with a burn time of 23 msec at 11, 12, and 13 volts, and a heating profile with multiple and varying duration heating pulses and delays between pulses (70-255 msec on/0-150 msec off). The resulting image density was measured on a MacBeth TR527 densitometer with Status-A filter (MacBeth Instrument Co., Newburgh, NY). The reflectance optical densities of the transferred images were 0.77, 1.28, and 1.62 on the first receptor, and 0.78, 1.25, and 1.62 on the second receptor at 11, 12, and 13 volts respectively.
The transferred images were then tested for ultraviolet light (UV) stability in an accelerated UV test device, UVcon (Atlas Electric Devices Co., Chicago, IL) equipped with eight 40 watt UVA-351 fluorescent lamps at 351 nm and 50° C. for 69 hours. The average loss in image density was 38.5% for the first receptor and 35.3% for the second receptor.
COMPARATIVE EXAMPLE C
A receptor sheet was prepared, tested, and evaluated as in Example 4 except that VYNS (see comparative Example A) was used in place of the MR-110 . The image densities were 0.71, 1.17, and 1.61 at 11, 12and 13 volts, respectively. Following accelerated UV exposure as described in Example 4, the resultant loss in image density was 64.7% on the average.
COMPARATIVE EXAMPLE D
A receptor sheet was prepared, tested, and evaluated as in Example 4 except that VAGH™ (a vinyl resin lopolymer manufactured by Union Carbide) was used in place of the MR-110. The image densities were 0.66, 1.19, and 1.58 at 11, 12, and 13 volts, respectively. Following accelerated UV exposure as described in Example 4, the resultant loss in image density was 52.3% on the average.
EXAMPLE 5
This example illustrates the use of a top coat release layer in the construction of the thermal dye transfer receptor sheet.
A dye receiving layer formulation having the following composition was prepared: MR-120 (34.72 wt %), Atlac™382 ES (34.72 wt %), Epon™ 1002 (6.17 wt %), Ferro® UV-Chek® AM-300 (13.34 wt %), 70% Troysol™ CD 1 (11.05 wt %). A 17% solids solution of the above mixture in MEK was coated onto 4 mil (0.1 mm) heat stabilized polyester at a wet thickness of 0.044 mm using a slot-die (slot-orifice) coater. The coating was dried to a coating weight of 6 g/m 2 by passing the coated polyester web at 15.2 m/s through a 30-foot oven having a temperature range of 65° to 93° C.
The receptor sheet coated above was then coated with a one weight percent solution of Dai-Allomer™ SP-711 (a polyvinyl butyral/siloxane copolymer) in MEK solvent which was then dried to give a coating weight of 0.1 g/m 2 .
The coated receptor sheets were imaged with cyan and magenta dye donor sheets and tested for dye image UV stability as described in Example 2.
TABLE 3______________________________________ Magenta Image Cyan Image Reflected Reflected Optical OpticalReceptor Sheet Density % Loss Density % Loss______________________________________No Topcoat13 volts 0.67 25.4 0.57 28.115 volts 1.32 30.3 1.18 32.217 volts 1.65 22.4 2.18 25.2SP-711 Topcoat13 volts 0.62 37.1 0.46 32.615 volts 1.18 28.8 1.00 34.017 volts 1.51 19.9 1.90 24.7______________________________________ | A dye transfer receptor sheet suitable for thermal dye transfer imaging is described. The receptor sheet provides excellent image stability characteristics. The receptor sheet comprises a substrate with a receiving layer of a vinyl chloride containing copolymer which has a glass transition temperature between 50° and 85° C., preferably about 59° and 65° C., a weight average molecular weight between about 10,000 and 100,000, preferably between 30,000 and about 50,000 g/mol, a hydroxyl equivalent weight between about 1500 and 4000, preferably about 1890 and about 3400 g/mol, a sulfonate equivalent weight between 9000 and 23,000, preferably between about 11,000 and about 19,200 g/mol, and an epoxy equivalent weight between about 500 and 7000, preferably about 1200 and about 6000 g/mol. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a division of U.S. patent application Ser. No. 10/659,196 filed Sep. 9, 2003 entitled “Quick Ceiling Fan Housing and Canopy Installation Assembly” the disclosure of which is incorporated herein in its entirety by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a ceiling fan anchoring bracket and housing assembly for quick and easy installation of the ceiling fan housing for either hugger and down-rod mounted fans. The bracket and housing assembly enables the user to install the ceiling fan housing to the anchoring bracket with relative ease. By employing the inventive design of the bracket and housing assembly, users are only required to align and engage one side of the housing to the hook-up pins on the bracket and push the opposite side of the housing onto the stationary lock-up pin on the bracket through spring or urging action to complete the installation.
BACKGROUND OF THE INVENTION
[0003] Ceiling fans are very common household and commercial appliances. Conventional ceiling fan housings are difficult to install due to the installer having to perform a number of difficult manoeuvres. Installing a conventional ceiling fan housing usually requires the installer standing on a stool or scaffold trying to work overhead with aligning the holes on both the anchoring bracket and the housing and inserting screws into the holes and try to tighten the screws with screw drivers all at the same time. The relatively heavy motor housing and rotor components of the hugger mounted fans add to the installation difficulty. Moreover, the limited space for turning the screws below the ceiling makes the screw tightening extremely arduous. Such traditional ceiling fan housing installation method is evidently unsatisfactory. It requires the installer great dexterity, patience, efforts and time in order to securely install the motor housing to the anchoring bracket.
[0004] It is therefore highly desirable to eliminate the need to screw the ceiling fan housing to the anchoring bracket so that a user only needs to simply push and snap the housing and secure the housing to the bracket for ready use.
[0005] Attempts have been made to achieve this objective in the prior art. For example, U.S. Pat. No. 6,200,099 (issued to Liao on Mar. 13, 2001) discloses a mounting mechanism without the need to use screws. It provides a frame for anchoring to the ceiling. Two pairs of base plates are used to secure the frame to the corresponding lugs on the upper circumference of the motor housing through a gap and slots and a resilient member. Even the Liao method avoids resorting to utilizing screws, it appears to be equally complicated in the assembly process, especially given the limited working space below the ceiling. U.S. Pat. No. 6,171,061 (issued to Hsu on Jan. 9, 2001) teaches a suspending bracket for receiving a ceiling fan housing without the need of screws. The Hsu system is somewhat simpler than the Liao system. It provides two diagonally opposed spring-biased steel balls partially embedded half way inside the blind holes of an anchoring frame. There are two corresponding holes located on the inwardly extending lugs positioned along the top rim of the fan housing. During installation, a user presses the housing against the anchoring frame and rotates the housing until the holes on the lugs engaged with the two steel balls, thereby locking the housing in position. However, the constant vibration of the motor housing will cause the ball-and-hole locking mechanism to degenerate and deteriorate over time and pose the hazardous danger of disengaging the fan housing from the anchor frame. Accordingly, it is beneficial to develop a mechanism which eliminates the need to use screws to fasten the fan housing to the anchoring bracket and, at the same time, promotes ease of installation and ensure permanent locking security.
[0006] It is also advantageous to be able to disengage the housing from the anchor bracket with simple manoeuvres and without having the need to resort to special tools.
SUMMARY OF THE INVENTION
[0007] The present invention provides a ceiling fan anchoring bracket and housing assembly for quick and easy installation of the ceiling fan housing to the bracket. The bracket and housing assembly enables the user to latchingly engage the housing to the ceiling anchoring bracket by simple actions with relative ease and without the need to use any tool.
[0008] It is a principal object of the invention to provide an improvement in the mechanical structure of a ceiling fan anchoring bracket and housing assembly which can be readily coupled together securely. Such bracket and housing assembly can be used for both types of ceiling fans, namely hugger mounted and down-rod mounted fans. For hugger mounting, the present invention is used to install the motor housing onto the ceiling bracket. For down-rod mounting, the present invention is used to install the down-rod canopy onto the ceiling bracket.
[0009] Accordingly, the present invention provides for a hugger ceiling fan anchoring bracket and fan housing assembly comprising (i) a fan anchoring bracket comprising a hook-up means, a stationary lock-up means and a stationary locking device housing engaging flange, wherein the stationary lock-up means comprises a locking plate mounted on the anchoring bracket and a pin protruding therefrom through a coil spring; whereby a spring biasing action exerted by the lock-up means is achieved by the coil spring cooperatively urging the pin against a corresponding hole on the fan housing and wherein the pin engages a hole in the stationary locking device housing engaging flange; (ii) the hook-up means and stationary lock-up means are mountably attached to the fan anchoring bracket and the stationary lock-up means capable of exerting spring biasing action to lock the fan housing in a secure position; and (iii) the fan housing equipped with corresponding means for engaging the hook-up means.
[0010] The present invention also provides for a down-rod ceiling fan anchoring bracket and canopy assembly which comprises similar components as disclosed in the foregoing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Advantages and features of the invention will become more apparent with reference to the following description of the presently preferred embodiment thereof in connection with the accompanying drawings, wherein like references have been applied to like components, in which:
[0012] FIG. 1 shows a perspective view of a user installing a hugger mounted ceiling fan motor housing to the anchoring bracket of the present invention with a simple push-up movement;
[0013] FIG. 2 a shows a side view of the anchoring bracket of a hugger mounted ceiling fan with the components of the locking device and hook-up pins of the present invention;
[0014] FIG. 2 b shows a side view of the hugger mounted ceiling fan housing provided with stationary lock-up pin engaging hole and hook-up pin engaging hole;
[0015] FIG. 3 a shows a bottom perspective view of the anchoring bracket of a hugger mounted ceiling fan of the present invention with the locking device and hook-up pins mounted thereon;
[0016] FIG. 3 b shows a top plane view of the anchoring bracket of a hugger mounted ceiling fan of the present invention with the locking device and hook-up pins mounted thereon;
[0017] FIG. 3 c shows a side view of the anchoring bracket of a hugger mounted ceiling fan of the present invention with the locking device and hook-up pins mounted thereon;
[0018] FIG. 3 d shows a top perspective view of the anchoring bracket of a hugger mounted ceiling fan of the present invention without the locking device and hook-up pins;
[0019] FIG. 4 a shows an enlarged perspective view of the components of the locking device of the present invention for a hugger mounted ceiling fan;
[0020] FIG. 4 b shows an enlarged perspective view of the hook-up pin of the present invention;
[0021] FIG. 5 a shows the housing of a hugger mounted ceiling fan engaging into the hook-up pins of the present invention;
[0022] FIG. 5 b shows the housing of a hugger mounted ceiling fan latchingly engaging into the stationary lock-up pin of the present invention; and
[0023] FIG. 6 shows the hugger mounted ceiling fan housing securely engaged into the anchoring bracket of the present invention;
[0024] FIG. 7 shows a perspective view of a down-rod ceiling canopy being installed onto the anchoring bracket of the present invention with a simple push-up movement;
[0025] FIG. 8 a shows a front and top perspective view of the anchoring bracket of a down-rod ceiling fan with the components of the locking device and hook-up pins of the present invention;
[0026] FIG. 8 b shows a perspective view of the down-rod ceiling canopy provided with one stationary lock-up pin engaging hole and two hook-up pin engaging hole;
[0027] FIG. 9 a shows a front and top perspective view of the anchoring bracket of a down-rod ceiling fan of the present invention;
[0028] FIG. 9 b shows a left side view of the anchoring bracket of a down-rod ceiling fan of the present invention;
[0029] FIG. 9 c shows a right side view of the anchoring bracket of a down-rod ceiling fan of the present invention;
[0030] FIG. 9 d shows a front view of the anchoring bracket of a down-rod ceiling fan of the present invention;
[0031] FIG. 9 e shows a top view of the anchoring bracket of a down-rod ceiling fan of the present invention;
[0032] FIG. 10 shows an enlarged perspective view of the components of the locking device of the present invention for a down-rod mounted ceiling fan;
[0033] FIG. 11 a shows a perspective view of the down-rod ceiling fan canopy of the present invention;
[0034] FIG. 11 b shows a front view of the down-rod ceiling fan canopy of the present invention;
[0035] FIG. 12 shows the L-shaped resilient C-wire mounted onto the side of the anchoring bracket of a down-rod ceiling fan and cooperatively urging the stationary lock-up pin against the bracket flange;
[0036] FIG. 13 a shows the first step in installing the canopy of the down-rod fan by aligning and hooking the canopy to the hook-up pins mounted on the anchoring bracket;
[0037] FIG. 13 b shows the second step in installing the canopy of the down-rod fan by pushing and locking the canopy to the stationary lock-up pin mounted on the anchoring bracket; and
[0038] FIG. 13 c shows the canopy of the down-rod fan securely engaged into the anchoring bracket of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] The anchoring bracket and housing assembly of the present invention is comprised of three parts, namely a ceiling anchoring bracket, a housing locking device mounted on the anchoring bracket and a ceiling fan motor housing for hugger mounted fans or, in the case of down-rod mounted fans, a canopy for latchingly attaching to the anchoring bracket with the aid of the locking device.
[0040] According to the present invention, a user can complete the housing installation of a hugger mounted fan by simply align and engage one side of the housing to the hook-up pins on the bracket and push the opposite side of the housing to securely latch onto the stationary lock-up pin on the bracket through a spring action (see FIG. 1 ). In the case of a down-rod mounted fan, the user can install the canopy to the ceiling anchoring bracket with similar latching manoeuvres (see FIG. 7 ). While the inventive concept for installing the motor housing (in the case of hugger mounted fans) and the canopy (in the case of down-rod mounted fans) is the same, for clarity of presentations, the two types of installations will be discussed separately below.
[0000] Hugger Mounted Fans
[0041] Referring to FIG. 2 a , an anchoring bracket 20 of the present invention is disclosed. The general shape of anchoring bracket 20 resembles a low-rise inverted “U” with the “wings” spreading out on both sides. The bracket has a ceiling anchoring plate 25 in the middle which is secured to the ceiling with conventional screws. There are a plurality of fan motor screws 27 provided on each side of ceiling anchoring plate 25 . Anchoring plate 25 has an arc welded J-hook 29 for convenient circuit connection. The foregoing components are well taught in the prior art.
[0042] A slightly convexed flange is provided at each end of the “wings” of anchoring bracket 20 . Each of the two ends of the “wings” is designated as the hook-up end and locking end, respectively. On the hook-up end, there is the hook-up pins housing engaging flange 23 . Directly opposite to the hook-up end is the locking end and it provides the locking device housing engaging flange 22 . According to one embodiment of the invention, two hook-up pin receiving holes 26 are located on flange 23 to receive hook-up pins 28 (see FIGS. 2 a and 3 a ). Optionally, hook-up pins 28 (see FIG. 4 b ) may be screwed into holes 26 (see FIGS. 3 a to 3 c ). The position of hook-up pins 28 corresponds to the hook-up pin engaging holes 36 on the motor housing 30 (see FIG. 2 b ).
[0043] On the locking device housing engaging flange 22 , a stationary lock-up pin receiving hole 24 is provided at around the middle of flange 22 (see FIG. 3 d ). Hole 24 receives the head portion X of stationary lock-up pin 12 , which latchingly engages to the lock-up engaging hole 34 on motor housing 30 (see FIG. 2 b ).
[0044] The locking device 10 is now described with reference to FIG. 2 a and FIG. 4 a . The locking device 10 is comprised of a stationary lock-up pin 12 with a head portion X, a body portion Y and a relatively short tail portion Z. The head portion X takes the shape of a round-headed cone in order to facilitate and ease the sliding and latchingly engaging action of the motor housing 30 when said housing is coupled to the stationary lock-up pin 12 . The base of the cone connects to body portion Y after passing a connector portion with larger diameter. The connector portion keeps the body portion Y inside the locking device housing engaging flange 22 . The body portion Y is inserted into coil spring 18 which has an approximate length as portion Y. Since the dimension of the base of the head portion X is larger than the diameter of coil spring 18 , the head portion X is exposed from spring 18 and protrudes outside the locking device housing engaging flange 22 through stationary lock-up pin receiving hole 24 . However, the tail portion Z of stationary lock-up pin 12 extends beyond spring 18 and abuts against the stationary lock-up pin recess 17 located on the vertical wedge of the L-shaped locking plate 14 . The L-shaped locking plate 14 is, in turn, mounted on the upper side of anchoring bracket 20 by locking plate screws 16 through locking plate screw holes 19 and unto bracket 20 , through locking plate receiving holes 21 from below. FIGS. 3 a , 3 b and 3 c illustrate the position of the locking device 10 relative to the other components on the anchoring bracket 20 .
[0045] FIGS. 5 a and 5 b illustrate the relatively easy installation of the ceiling fan motor housing 30 onto the anchoring bracket 20 by latchingly engaging the locking device 10 of the present invention. The user first aligns the two hook-up pin engaging holes 36 with the two hook-up pins 28 on ceiling anchoring plate 25 and moves the housing towards the plate (as in the direction indicated by arrow A in FIG. 5 a ) until the pins 28 are engaged to the holes 36 . Once the hook up is completed, the user then proceeds to lock up the housing by pushing housing 30 upward (as in the direction indicated by arrow B in FIG. 5 b ). With the upward pushing motion, the stationary lock-up pin 12 latchingly engages hole 34 on the motor housing when the latter comes into contact with head portion X of stationary lock-up pin 12 on the anchoring bracket 20 . Due to the round-headed cone shape of the head portion X of stationary lock-up pin 12 , the rim of housing 30 forces the head portion X of stationary lock-up pin 12 to retract (as housing 30 is pushed up) and then to urge outward and to lock into stationary lock-up pin engaging hole 34 via the coil spring biasing action.
[0046] FIG. 6 shows the ceiling fan motor housing 30 securely installed onto the anchoring bracket 20 , with the hook-up pins 28 and head portion X of stationary lock-up pin 12 protruding outward from the hook-up pin engaging holes 36 and stationary lock-up pin engaging hole 34 , respectively.
[0000] Down-Rod Mounted Fans
[0047] Inventive features of the present invention directed to the down-rod mounted type of fans are now described with reference to FIGS. 7 to 13 c.
[0048] In FIGS. 8 a and 8 b , an anchoring bracket 200 suitable for use with down-rod mounted fan canopy 300 according to the present invention is disclosed. The anchoring bracket 200 takes the shape of an “U” with two ceiling anchoring plates 205 spreading out like a pair of “wings” on each side. At the bottom of the “U-shaped” bracket there is an opening for convenient placement of the down-rod (not shown). The ceiling anchoring plates 205 are used to secure the bracket to the ceiling using conventional screws. One of the anchoring plates 205 has an arc welded J-hook 209 for convenient circuit connection. As in the case of the hugger mounted fans, these components are known in the prior art.
[0049] A convexed flange is provided at the end of each of the “wings” of anchoring bracket 200 . Each of the two ends of the “wings” is designated as the hook-up end and locking end, respectively. On the hook-up end, there is the hook-up pins canopy engaging flange 203 . Directly opposite to the hook-up end is the locking end and it provides the stationary locking device canopy engaging flange 202 . According to a preferred embodiment , two hook-up pin receiving holes 206 are located on flange 203 to receive hook-up pins 208 (see FIG. 8 a ). Optionally, hook-up pins 208 may be screwed into holes 206 (see FIG. 8 a ). The position of hook-up pins 208 corresponds to the hook-up pin engaging holes 306 on the down-rod canopy 300 (see FIG. 8 b ). FIGS. 9 a , 9 b , 9 c , 9 d and 9 e illustrate the perspective, left, right, front and top views of the anchoring bracket 200 .
[0050] On the stationary locking device canopy engaging flange 202 , a stationary lock-up pin receiving hole 204 is provided at around the middle of flange 202 (see FIG. 9 c ). Hole 204 receives the head portion X of stationary lock-up pin 102 , which latchingly engages to the lock-up engaging hole 304 on the down-rod canopy 300 (see FIG. 8 b ).
[0051] The stationary locking device 100 is now described with reference to FIGS. 8 a , 10 and 12 . The stationary locking device 100 is comprised of a stationary lock-up pin 102 with a head portion X, a body portion Y and a relatively short tail portion Z. The head portion X takes the shape of a round-headed cone. The base of the cone connects to body portion Y after passing a connector portion with larger diameter. The connector portion keeps the body portion Y inside the stationary locking device canopy engaging flange 202 . Since the dimension of the base of the head portion X is larger than the diameter of the stationary lock-up pin receiving hole 204 , the head portion X is protruded outside the stationary locking device canopy engaging flange 202 through stationary lock-up pin receiving hole 204 . The body portion Y is kept in place by the L-shaped locking plate 104 . The tail portion Z of stationary lock-up pin 102 emerges and extends beyond the stationary lock-up pin recess 107 located on the vertical wedge of the L-shaped locking plate 104 . The short tail portion Z has a shallow longitudinal slot in the middle to cooperatively and biasingly receive the urging end 112 of the L-shaped C-wire 108 (see FIG. 12 ). The L-shaped locking plate 104 is mounted on the under side of anchoring bracket 200 by locking plate screw 106 through locking plate screw hole 109 . FIG. 10 also depicts two views of the L-shaped resilient C-wire 108 having a loop end 110 for screw 106 to fasten the C-wire to anchoring hole 201 (see also FIGS. 9 c and 12 ) on anchoring bracket 200 . As can be seen from FIG. 12 , the L-shaped resilient C-wire 108 exerts biasing force to urge locking pin 102 against the canopy flange 202 .
[0052] FIGS. 13 a , 13 b and 13 c illustrate the relatively easy installation of the down-rod canopy 300 onto the anchoring bracket 200 using the stationary locking device 100 of the present invention. The user first aligns the two hook-up pin engaging holes 306 with the two hook-up pins 208 on ceiling anchoring plate 205 and moves the canopy towards the plate (as in the direction indicated by arrow A in FIG. 13 a ) until the pins 208 are engaged to the holes 306 . Once the hook up is completed, the user then proceeds to lock up the canopy by pushing canopy 300 upward (as in the direction indicated by arrow B in FIG. 13 b ). With the upward pushing motion, the stationary lock-up pin 102 latchingly engages hole 304 on the canopy when the latter comes into contact with head portion X of stationary lock-up pin 102 on the anchoring bracket 200 and forces the head portion X of stationary lock-up pin 102 to retract (as canopy 300 is pushed up) and then to urge outward and to lock into stationary lock-up pin engaging hole 304 via the C-wire biasing action.
[0053] FIG. 13 c shows the down-rod canopy 300 securely installed onto the anchoring bracket 200 , with the hook-up pins 208 and head portion X of stationary lock-up pin 102 protruding outward from the hook-up pin engaging holes 306 and stationary lock-up pin engaging hole 304 , respectively.
[0054] It is readily understood that the number of stationary lock-up pin and hook-up pin in either the hugger mounted fans or down-rod mounted fans is not limited to those disclosed herein. Likewise, any suitable biasing means able to urge the stationary lock-up pin against the stationary lock-up pin engaging hole on the housing or canopy is within contemplation of the present invention. The coil spring 18 and L-shaped resilient C-wire 108 are merely examples of preferred embodiments disclosed in this invention herein.
[0055] Hence, although the present invention has been described with referenced to two preferred embodiments, it will be appreciated by those skilled in the art that various modifications, alternations, variations, and substitutions of parts and components may be made without departing from the spirit and scope of the invention. Therefore, the present application is intended to cover such modifications, alternations, variations, and substitutions of parts and components. | A ceiling fan anchoring bracket and housing assembly for quick and easy installation of the ceiling fan housing for either hugger or down-rod fans is disclosed. The assembly comprises of hook-up pins and stationary lock-up pin fastened on and protruding from the anchoring bracket. The stationary lock-up pin latchingly locks the housing of the fan by spring or urging mechanism. The bracket and housing assembly enables the user to install the ceiling fan housing to the anchoring bracket without having to resort to using tools. All a user needs to do is to align and engage one side of the housing to the hook-up pins on the bracket and push the opposite side of the housing onto the stationary lock-up pin on the bracket through a spring action to complete the installation. | 8 |
FIELD OF THE INVENTION
This invention relates to the reduction of nitrogen oxides and the thermal oxidation of organics, and more particularly, to a device and method for the reduction of nitrogen oxides and the thermal oxidation of organics in a net oxidizing environment of a gas and particulate matter stream from industrial and vehicle exhaust.
BACKGROUND OF THE INVENTION
Destruction or conversion of atmospheric pollutants in industrial gas streams and internal combustion engine exhaust streams has been a long-standing research and development goal. Such atmospheric pollutants include products of incomplete combustion, such as carbon monoxide and unburned hydrocarbons, oxides of nitrogen [“NOx”], and carbonaceous particulate matter [“PM”].
Lean-burning engines, such as diesel engines and lean-burning gasoline or natural gas engines, often emit levels of pollutants above regulatory limits. In response to air quality regulations, vehicle manufacturers employ pollution control devices in internal combustion engine exhaust systems to reduce these emissions. Traditional gasoline engine pollution control devices employ a ceramic honeycomb monolith or a packed bed of pellets having a coating of a noble metal catalyst. Such devices catalyze the reactions of carbon monoxide and unburned hydrocarbons with oxygen, typically at approximately 260° C. to 427° C. (500° F. to 800° F.). Other devices employ catalysts that also catalyze the reaction of oxides of nitrogen. Unfortunately, two factors render such catalytic devices alone insufficient for treating vehicle engine exhaust (especially diesel engine) and similar industrial emissions. First, the catalytic devices are ineffective at destroying PM, which is present in engine gas streams, especially those from diesel engines. Second, the PM and other particulates deposit on the monolith, thereby preventing gaseous constituents from reaching the catalytic material, or possibly deactivating or poisoning the catalyst. In general, conventional three-way-catalysts fail to reduce NOx under lean-burn (that is, oxygen-rich) conditions common to many internal combustion engines.
Internal combustion engines are the subject of regulations limiting NOx emissions. The simultaneous emission limits for both particulate matter and NOx presents a unique problem because the two pollutants typically have an inverse relationship in engine exhaust. Internal combustion engines generally can be configured and tuned to produce an exhaust stream having low PM and high NOx concentrations or, alternatively, high PM and low NOx concentrations. Traditionally, engines that employ oxidation catalyst devices may be adjusted to minimize NOx formation because of the catalysts' inability to reduce NOx. Such adjustments may compromise engine efficiency and performance.
Although not generally employed in reducing NOx emissions from internal combustion engines, various techniques exist for reducing NOx emissions from gas streams in other applications. One technique for reducing NOx emissions is selective catalytic reduction (SCR), which reduces NOx in the presence of a reducing agent, such as of ammonia (NH 3 ), over a catalyst. Typically, selective catalytic NOx reduction is employed with exhaust stream temperatures in the range of 288° C.-427° C. (550° F.-800° F.). SCR catalysts have the limitations discussed herein above.
Another approach for removing NOx is selective non-catalytic reduction (SNCR), which employs a chemical that selectively reacts, in the gas phase, with NOx in the presence of oxygen at a temperature greater than 621° C. (1150° F.). Chemical NOx reduction agents used in such processes include ammonia (NH 3 ), urea (NH 2 CONH 2 ), cyanuric acid (HNCO) 3 , iso-cyanate, hydrazine, ammonium sulfate, atomic nitrogen, melamine, methyl amines, and bi-urates.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a system and method or reducing pollutant emissions from internal combustion engines and industrial exhaust gas streams. Specifically, an object of the present invention is to provide a system and method for reducing NOx, and oxidizing PM and oxidizable constituents in an engine or industrial exhaust stream. It is an object to provide such a system and method in a single, compact device, especially one suitable for use in a mobile vehicle engine.
It is another object of the present invention to provide a device and method for the integrated, substantially-simultaneous oxidation and reduction, especially thermal oxidation of organics and catalytic reduction of NOx, of an exhaust gas stream.
It is a further object of the present invention to provide a system and method for reducing NOx emissions from an engine exhaust stream under lean-burn (that is, oxygen-rich) conditions.
It is yet a further object of the present invention to provide a thermal oxidation and catalytic reduction system having a catalytic surface to reduce NOx under lean-burn conditions.
It is yet a further object of the present invention to provide film injection techniques to enhance contact between a reactant and a catalyst.
It is yet a further object of the present invention to provide techniques for the injection of supplementary fuel into a system for the thermal oxidation of organics and catalytic NOx reduction in such a manner that the performance of the NOx reduction catalyst is enhanced.
According to the present invention, a thermal oxidation and catalytic reduction system arranged in a compact, multi-spiral, recuperative configuration is provided that includes two interspaced, coiled sidewalls that form a spiral inlet passage and a spiral outlet passage, and a central chamber. A thermal oxidation zone, which is preferably disposed in the central chamber, may be located between the inlet and outlet (that is, entrance and exit) passages, which form a spiral, counter-current heat exchanger. A matrix of porous inert media may be disposed within each one of the spiral passages and in the central chamber. The oxidation reaction zone, which is in flow communication with the spiral inlet passage and spiral outlet passage, receives heat primarily by convection from the oxidized gases and loses heat primarily by radiation to the matrices, which are in intimate contact with the gas stream.
The thermal oxidation and catalytic reduction system utilizes a catalytic surface to reduce NOx. Preferably a lean-NOx catalyst is employed in the appropriate regions of the thermal oxidation and catalytic reduction system—that is, proximate the inlet (for conditions in which the inlet gas stream is within or belowthe range at which the particular catalyst may be effective) and the outlet. The catalytic surface may be disposed either on the sidewalls forming the spiral passages, on the media, or in a combination of the media and sidewalls. In the embodiment in which the catalytic surface is disposed on one or more sidewalls, the matrix may be omitted from the passage adjacent to the catalytic surface.
The matrices foster stable oxidation of the reacting gas at low temperatures (for example 788° C.-1093° C. (1450° F.-2000° F.)) within the reaction zone of a thermal oxidizer portion of the present system) compared with premixed flames. Thus, the system according to the present invention diminishes the formation of oxides of nitrogen. Further, the matrices provide a highly radiative environment and long residence times, which promote the destruction of gas phase organics, CO, and PM. Further, the geometry of the present invention provides regions that have temperature ranges that are well-suited for a wide variety of NOx reduction techniques. Specifically, the relatively smooth temperature profile of the gas stream within the spiral passages, compared with combustion processes using (for example) premixed flames, provides relatively long residence times within a wide range of temperatures to enable the present invention to employ a broad range of emission control techniques, especially those relating to NOx reduction. Further, the present invention, because of the stable oxidation conditions created therein, is well-suited to the wide variations in flow rate and temperature (approximately 70° C. to 600° C.) common to engine exhaust streams.
According to another aspect of the present invention, a thermal oxidizer is integrated with a lean-NOx catalyst that utilizes a reducing agent or reactant stream, which includes, among other constituents, hydrogen, hydrocarbons, and carbon monoxide, to chemically reduce NOx to diatomic nitrogen [“N 2 ”]. The integration of the oxidation process and the lean-NOx reduction process enables the reducing agent both to reduce NOx and to provide supplemental fuel to enhance the oxidation process, as well as providing a compact system.
In another aspect of the present invention, a thermal oxidation and catalytic reduction system is provided having a thermal oxidation zone, a catalytic surface disposed on the concave surfaces of the sidewalls, and film-injection means to supply reactants (especially hydrogen, hydrocarbons, and carbon monoxide) to the catalytic surface in greater concentration than if the reactants were premixed in the gas stream. The concave surfaces of the sidewalls are the preferred substrate for the catalytic surface to avoid boundary layer separation of the gas stream over the convex surface. The effectiveness and performance of the catalytic reduction of NOx may thus be enhanced. The film injection for the purpose of enhancing effectiveness of lean-NOx catalysts is preferably employed in the exterior portions (defined angularly) of the sidewalls.
The film-injection also provides cooling to the catalytic surface, thereby enabling the catalytic surface to be disposed further into the thermal oxidation and catalytic reduction system and yet operate within its optimum temperature range. The resulting augmented catalytic surface area may provide increased NOx reduction without increasing oxidizer size.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the thermal oxidation and catalytic reduction system according to an embodiment of the present invention;
FIGS. 2A through 2G are views of a section of the thermal oxidation and catalytic reduction system of FIG. 1 showing various arrangements of the catalytic surface;
FIG. 3 is a schematic view of the thermal oxidation and catalytic reduction system according to another aspect of the present invention;
FIG. 4 is a schematic view of a thermal oxidation and catalytic reduction system according to another aspect of the present invention;
FIG. 5 is a perspective view of a portion of a sidewall of the thermal oxidation and catalytic reduction system shown in FIG. 4 to illustrate another aspect of the present invention;
FIG. 6 is a schematic view of a thermal oxidation and catalytic reduction system according to another aspect of the present invention;
FIG. 7 is a typical temperature profile of the gas stream according to the embodiment of the present invention shown in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 to illustrate a first embodiment of the present invention, a thermal oxidation and catalytic reduction system 10 a comprises a first coiled sidewall 18 that is interspaced with a second coiled sidewall 20 to form a spiral inlet passage 22 and a spiral outlet passage 24 . The first sidewall 18 forms an exterior portion 26 and an interior portion 28 . The second sidewall 20 forms an exterior portion 30 and an interior portion 32 . The general configuration of such a spiral device may be broadly referred to as as “swiss roll.” The terms “exterior portion” and “interior portion,” as used to define portions of the sidewalls herein and in the appended claims, refer to angular portions of the sidewalls such that the exterior portion generally has a greater radius of curvature than the interior portion. The term exterior portion is further defined below.
The first sidewall 18 and the second sidewall 20 each have a concave surface 34 and a concave surface 38 , respectively, which each face the center of thermal oxidation and catalytic reduction system 10 a , and a convex surface 36 and a convex surface 40 , respectively, which each face away from the center of the thermal oxidation and catalytic reduction system 10 a . A cylinder 44 is disposed near the center of thermal oxidation and catalytic reduction system 10 a to form a central chamber 46 having a heating means 49 disposed therein. Alternatively, rather than being formed by a cylinder, a central chamber may be formed between spiral, spaced-apart, opposing ends of sidewalls, as shown in co-pending U.S. patent application Ser. No. 09/072,851, entitled “A Device for Thermally Processing a Gas Stream, and Method for Same,” which is incorporated herein by reference in its entirety.
Within the spiral inlet passage 22 is an inlet passage matrix 50 of porous inert media; within the spiral outlet passage 24 is an outlet passage matrix 52 of porous inert media; and within the central chamber 46 is a central chamber matrix 54 of porous inert media. Matrices 50 , 52 , and 54 are shown in FIG. 1 in cut-away sections of the thermal oxidation and catalytic reduction system 10 a for clarity. Specifically, matrix 50 , matrix 52 , and matrix 54 each comprise a porous bed of solid, heat-resistant media through which a gas stream 4 passes. The present invention broadly encompasses matrices 50 , 52 , and 54 in an combination. For example, matrices 50 and 52 may be wholly omitted from their respective passages (that is, only the central chamber 46 has a matrix); matrix 50 may be omitted from all or a potion of spiral inlet passage 22 ; matrix 52 may be omitted from all or a portion of spiral outlet passage 24 ; matrices 50 and 52 may be partially omitted from their respective passages (that is, the central chamber 46 and portions of the passages 22 and 24 have matrices); matrix 54 may be omitted from a portion of central chamber 46 (that is, all or portions of spiral inlet passage 22 and/or spiral outlet passage 24 —including any combination thereof—have matrices 50 and 52 , respectively, and a portion of central chamber 46 has matrix 54 ).
The media of matrices 50 , 52 , and 54 encompass a bed of any ceramic, metal, or other heat-resistant media, including: metal wool, balls, chunks, granules (preferably approximately 0.25″ to 1″″ diameter for the balls, chunks, or granules); saddles, preferably approximately 0.5″ to 1.5″ nominal size; pall rings; foam, preferably having a void fraction of approximately 90% and about ten to thirty pores per inch; and honeycomb. Metal wool or foam are preferred. Regardless of the type or material of the media, interstitial diameters of approximately 0.125″ to 1.0″ are preferred.
Although the Figures generally use balls to represent the media, the present invention encompasses any combination of the above or other types and sizes of media, whether used separately or in combination, and whether randomly or structurally arranged. Further, the media may include an engineered matrix portion that has two or more flow control portions. The materials of the media are chosen according to their heat transfer properties. The size, composition, and material selections are determined to obtain a desired overall heat transfer and catalytic reaction characteristic. U.S. patent application Ser. No. 08/921,815, entitled “Matrix Bed For Generating Non-Planar Reaction Wave Fronts and Method Thereof”, filed Sep. 2, 1997, and U.S. patent application Ser. No. 08/922,176, entitled “Method of Reducing Internal Combustion Engine Emissions, and System for Same,” filed Sep. 2, 1997, which are each incorporated herein by reference in their entireties, describe the engineered matrix and the media in greater detail.
Further, co-pending U.S. patent application Ser. No. 09/072,851 describes aspects and features of a spiral, thermal processing device, including, for example, devices and methods for controlling a thermal oxidizer, heating means 49 , means for providing inlet and outlet devices, and the like, that may be applied to the present invention. Heating means, and operating and control techniques are also described in U.S. patent application Ser. No. 08/922,176.
Spiral inlet passage 22 and spiral outlet passage 24 , because of the oxidation reaction occurring preferably within the central chamber 46 , generally form an inlet passage low temperature region 58 , an outlet passage low-temperature region 60 , an inlet passage high-temperature region 62 , and an outlet passage high temperature region 64 .
According to one aspect of the present invention, a catalytic surface 70 a may be disposed on first sidewall 18 in the inlet passage low-temperature region 58 , and another catalytic surface 70 b may be disposed on second sidewall 20 in the outlet passage low-temperature region 60 . Catalytic surfaces 70 a and 70 b preferably are disposed proximate the exterior ends of the inlet passage 22 and/or the outlet passage 24 , respectively, at locations in which the catalytic surfaces 70 a and 70 b would contact gases near the optimum catalytic temperature range for the catalyst formulation. The term “low-temperature region,” as used herein and in the appended claims, refers to a portion of the thermal oxidation and catalytic, reduction system 10 a that corresponds to a temperature range within which a lean-NOx catalyst may be operative to catalytically reduce NOx. It is understood that the “low-temperature region” may be proximate the inlet of the spiral inlet passage 22 , proximate the outlet of the spiral inlet passage 24 , or within either passage. Further, it is understood that the term “exterior portion,” when used to refer to portions of a sidewall, also generally refers to the region of the sidewall having a temperature range within which a lean-NOx catalyst may be operative to catalytically reduce NOx.
The temperature range of the low-temperature regions (that is, the regions within the device that the catalytic surface is disposed) may be chosen, in part, according to the optimum operating temperature range of the catalyst, the temperature at which the rate of creation of NOx from the fuel equals the rate at which NOx is reduced (which may set an upper effective temperature limit), mechanical properties of the catalytic material and its substrate, and like characteristics of the particular application. Catalytic surfaces 70 a and 70 b (as well as surface 70 c , which will be discussed below) preferably are formed of a catalyst material suitable for low-temperature reduction of NOx in lean, gasoline or diesel engine exhaust (or that from a similar industrial process). Although any suitable catalyst may be employed, a lean-NOx catalyst is preferred. An example of such a lean-NOx catalyst is one that incorporates ircn (II)-complex impregnated molecular sieves and is further treated with [Pd(NH 3 ) 4 ]CL 2 —as described in “Development of a Lean-NOx Catalyst Containing Metal-Ligand Complex Impregnated Molecular Sieves,” Paul, et al., SAE Technical Paper Series 962050 (1996). The molecular sieve may, for example, comprise the type MCM-41 available from Mobil Oil Corp. Such a catalyst has an optimum effectiveness when operating at a temperature of approximately 288° C. to 427° C.
FIGS. 2A through 2G show various configurations of catalytic surfaces 70 a and 70 b on a section of sidewall 18 and/or sidewall 20 in the low-temperature regions 58 and 60 of the spiral passages 22 and 24 . According to the embodiment of the invention shown in FIG. 1, the porous inert media of matrices 50 and 52 is absent from the passages 22 and 24 that contain catalytic surfaces 70 a and 70 b . In FIGS. 2A through 2G, catalytic surfaces 70 a and 70 b are represented in a cross-hatched pattern for clarity.
FIG. 2A shows catalytic surface 70 a disposed on first sidewall concave surface 34 and second sidewall convex surface 40 , and catalytic surface 70 b disposed on second sidewall concave surface 38 and first sidewall convex surface 36 . Catalytic surface 70 a , therefore, is disposed on both the concave and convex surfaces of the low temperature region 58 of the spiral inlet passage 22 , and catalytic surface 70 b is disposed on both the concave and convex surfaces of the low temperature region 60 of the spiral outlet passage 24 . FIG. 2B shows catalytic surface 70 b disposed on first sidewall convex surface 36 and the second sidewall concave surface 38 so as to line opposing sides of spiral outer passage 24 . FIG. 2C shows catalytic surface 70 a disposed on first sidewall concave surface 34 and second sidewall convex surface 40 so as to line opposing sides of spiral inlet passage 22 . FIG. 2D shows catalytic surface 70 a disposed on first sidewall concave surface 34 so as to line the radially outward side of spiral inlet passage 22 . FIG. 2E shows catalytic surface 70 a disposed on second sidewall convex surface 40 so as to line the radially inward side of spiral inlet passage 22 . FIG. 2F shows catalytic surface 70 b disposed on the second sidewall concave surface 38 so as to line the radially outward side of spiral outlet passage 24 . FIG. 2G shows catalytic surface 70 b disposed on the first sidewall convex surface 36 so as to line the radially inward side of spiral outlet passage 24 .
In the embodiments of the invention shown in FIG. 2A, catalyst material directly communicates with the gas stream 4 within both the spiral inlet passage 22 and the spiral outlet passage 24 . In the embodiments shown in FIGS. 2C, 2 D, and 2 E, catalytic surface 70 a directly communicates with gas stream 4 within the spiral inlet passage 22 , but the spiral outlet passage 24 lacks direct contact with catalyst material (that is, these embodiments lack catalyst surface 70 b ). In the embodiments shown in FIGS. 2B, 2 F, and 2 G, catalytic surface 70 b directly communicates with gas stream 4 within the spiral outlet passage 24 , but the spiral inlet passage 22 lacks direct contact with catalyst material (that is, these embodiment lacks catalyst surface 70 a ). The term “directly communicate,” as used herein and in the appended claims in conjunction with a specified passage and a surface, refers to direct contact between the specified passage and that surface, but excludes contact between the surface and the gas stream in the passages other than those expressly specified.
The length along sidewall 18 and/or 20 on which catalytic surface 70 a and/or 70 b are disposed will vary according to parameters associated with the particular application, including, for example, gas stream 4 inlet temperature and desired outlet temperature, gas flow rates, heat transfer characteristics of the gas, and heat transfer characteristics and configuration of the thermal oxidation and catalytic reduction system (including, for example, passage width, length, height, number of turns, and like geometric and mechanical parameters), and others, as will be understood by those familiar with such devices and applications. Further, film-injection techniques, as described herein, may enable catalytic surfaces 70 a and/or 70 b to maintain a temperature within the catalysts' target operating range, even while the local gas stream 4 temperature is higher, because the film injection may provide cooling. The catalyst material that forms catalytic surfaces 70 a and 70 b is preferably electroplated, sputtered, or applied by a series of washcoat methods onto sidewalls 18 and 20 , which are preferably formed of metal, although other conventional methods of forming catalytic surfaces 70 a and 70 b on sidewalls 18 and 20 may be employed.
The device may be arranged such that a matrix of porous inert media is disposed on the inlet side (that is, upstream) of catalytic surface 70 a in the spiral inlet passage 22 , and such that a matrix of porous inert media is disposed on the outlet side (that is, downstream) of catalytic surface 70 b in the spiral outlet passage 24 . The design parameters of such matrices, which are not shown in the figures, may be determined by heat transfer, pressure drop, and gas characteristics (among other similar variables), as will be understood by those familiar with the particular use and with the devices and methods described herein.
Referring to FIG. 3 to illustrate another aspect of the present invention, a thermal oxidation and catalytic reduction system 10 b is structurally similar to thermal oxidation and catalytic reduction system 10 a (shown in FIG. 1 ), except for the inlet passage matrix 50 , the outlet passage matrix 52 , and catalytic surfaces. In the embodiment shown in FIG. 3, matrices 50 and 52 are disposed within spiral inlet passage 22 and spiral outlet passage 24 proximate the exterior portions 26 and 28 of sidewalls 18 and 20 , respectively (that is, within low temperature regions 58 and 60 ). A catalytic surface 70 c is coated onto the media of matrices 50 and 52 to provide large contact surface area with the gas stream 4 . In addition to having both matrices coated with catalytic surface 70 c , the present invention encompasses having the catalytic surface 70 c disposed only the spiral inlet matrix 50 , only on the spiral outlet matrix 52 , and any combination of matrix 50 , matrix 52 and portions of the sidewalls (that is, by employing catalytic surface 70 a and/or 70 b as shown in FIGS. 2 A through 2 G). Catalytic surface 70 c may be formed on the surface of the matrices 50 and/or 52 by a series of washcoat methods if the media is ceramic or other non-conducting substrate, or by electroplating if the media is metal wool or other electrically conducting substrate. Sputtering may also be used.
Referring to FIGS. 1 and 3 to illustrate another aspect of the present invention, system 10 a , 10 b , or 10 c may employ multiple, sequentially-disposed catalytic surfaces, each of which are formed of a unique catalyst formulation. Specifically referring to FIG. 1, catalytic surface 70 a comprises a first catalytic surface 70 a ′, a second catalytic surface 70 a ″, and a third catalytic surface 70 a ′″. Catalytic surfaces 70 a ′, 70 a ″, and 70 a ′″ are preferably disposed angularly adjacent such that surface 70 a ′ is disposed within spiral inlet passage 22 relatively upstream (that is, as defined by the path of gas stream 4 ) of surface 70 a ″, which, in turn, is upstream of surface 70 a ′″. First catalytic surface 70 a ′ may be formed of a lean-NOx catalyst formulation that has an effective temperature range that is optimized for the expected gas and surface temperatures proximate surface 70 a ′. Likewise surfaces 70 a ″ and 70 a ′″ may be formed of lean-NOx catalyst formulations having temperature ranges that are similarly optimized. For example, the catalyst forming surface 70 a ′ may be a lean-NOx catalyst that is optimized to catalyze the reduction of NOx over a temperature range of 250° C. to 350° C., and is disposed at a location within spiral inlet passage 22 such that surface 70 a ′ encounters temperatures approximately within that range. Surfaces 70 a ″ and 70 a ′″ may be optimized to catalyze the reduction of NOx over temperature ranges approximately of 350° C. to 450° C., and 450° C. to 550° C., respectively, and may be correspondingly and respectively disposed within spiral inlet passage 22 downstream of surface 70 a ′. Surfaces 70 a ′, 70 a ″, and 70 a ′″ may be contiguous or may be disposed with gaps therebetween.
Similarly, catalytic surface 70 b comprises a first catalytic surface 70 b ′, a second catalytic surface 70 b ″, and a third catalytic surface 70 b ′″. Catalytic surfaces 70 b ′, 70 b ″, and 70 b ′″ are preferably disposed angularly adjacent such that surface 70 b ′ is disposed within spiral outlet passage 22 relatively upstream of surface 70 b ″, which, in turn, is upstream of surface 70 b ′″. Surfaces 70 b ′, 70 b ″, and 70 b ′″ may be formed of lean-NOx catalyst formulations as described above with reference to surfaces 70 a ′, 70 a ″, and 70 a′″.
Referring specifically to FIG. 3, catalytic surface 70 c comprises a first catalytic surface 70 c ′, a second catalytic surface 70 c ″, and a third catalytic surface 70 c ′″. Catalytic surfaces 70 c ′, 70 c ″, and 70 c ′″ are preferably disposed angularly adjacent such that surface 70 c ′ is disposed within matrix 50 relatively upstream (that is, as defined by the path of gas stream 4 ) of surface 70 c ″, which, in turn, is upstream of surface 70 c ′″. Catalytic surfaces 70 c ′, 70 c ″, and 70 c ′″ are also disposed angularly adjacent within spiral outlet passage 24 such that surface 70 c ′ is disposed within matrix 52 relatively upstream (that is, as defined by the path of gas stream 4 ) of surface 70 c ″, which, in turn, is upstream of surface 70 c ′″. Catalytic surfaces 70 c ′, 70 c ″, and 70 c ′″ may be formed of lean-NOx catalyst formations and disposed according to the descriptions referring to surfaces 70 a ′, 70 a ′″, 70 a ′″, 70 b ′, 70 b ″, and 70 b′″.
According to another aspect of the present invention, a means for injecting a film of reactants proximate the catalytic surfaces 70 a and/or 70 b is provided. Referring specifically to FIG. 4 and FIG. 5 to illustrate a first embodiment of the film-injection means, a channel 76 a enables flow of a reactant stream 6 a to communicate with catalytic surface 70 a , which is disposed on concave surface 34 of first wall 18 . A spiral channel plate 74 a is disposed substantially parallel to first side wall 18 so as to form reactant channel 76 a between an inside, concave surface 78 a of channel plate 74 a and the convex surface 36 of first side wall 18 . Preferably, reactant channel 76 a is disposed along substantially the entire length of catalytic surface 70 a . Plural transpiration holes 80 are disposed through catalytic surface 70 a and through first sidewall 18 such that the reactant stream 6 a is in fluid communication with spiral inlet passage 22 .
Similarly, another film injection means may comprise a spiral channel plate 74 b that creates a reactant channel 76 b . Spiral channel plate 74 b is disposed substantially parallel to first sidewall 20 so as to form reactant channel 76 b between an inside, concave surface 78 b of channel plate 74 b and the convex surface 40 of second side wall 20 . Preferably, reactant channel 76 b is disposed along substantially the entire length of catalytic surface 70 b . Plural transpiration holes 80 are disposed through catalytic surface 70 b and through second side wall 20 such that a reactant stream 6 b is in fluid communication with the spiral outlet passage 24 .
Channels 76 a and/or 76 b may be formed by suitable means for producing such a channel, including dimpling channel plate 74 a and/or 74 b (as is described in co-pending application Ser. No. 08/922,176), by stamping channels into one or both of plates 74 a and/or 74 b , by utilizing stand-offs or studs to space the plates apart, or other means, as will be understood by those familiar with such techniques. Similarly, sidewall 18 and/or 20 may be formed with dimples or channels to form channels 76 a and/or 76 b . Reactant streams 6 a and 6 b comprise reducing agents that are effective for use with the catalyst material forming catalytic surfaces 70 a , 70 b , and 70 c . Specifically, for a lean-NOx catalyst, reactant streams 6 a and 6 b may include hydrogen, hydrocarbons, and/or carbon monoxide. For example, a lean-NOx catalyst has demonstrated NOx reduction in a diesel engine exhaust stream by utilizing a 10 gram per hour stream of diatomic hydrogen [“H2”] for cars, and a 20 to 50 gram per hour stream of H2 for vans and trucks. Lean-NOx catalytic surfaces 70 a , 70 b , and 70 c may also utilize hydrogen, hydrocarbons, and carbon monoxide reactants already present in gas stream 4 , or created while gas stream 4 is within the thermal oxidation and catalytic reduction system 10 a , 10 b , or 10 c , in addition to utilizing reactants supplied by streams 6 a and 6 b . Further, the constituents and constituent concentrations of stream 6 a may vary from those of stream 6 b to optimize catalysis with the particular catalyst material used to form catalytic surfaces 70 a and 70 b , respectively. Providing reactant streams 6 a and 6 b to the thermal oxidation and catalytic reduction system may be by conventional means.
Referring to FIG. 6 to illustrate another embodiment of the film injection means, injection ports 82 a are disposed proximate the concave surface 34 of first side wall 18 to enable injection of reactant stream 6 a into spiral inlet passage 22 along catalytic surface 70 a . Similarly, injection ports 82 b may be disposed proximate the concave surface 38 of second sidewall 20 to enable injection of a reactant stream 6 b into spiral inlet passage 24 along catalytic surface 70 b . Injection ports 82 a and 82 b may be formed in a shape that promotes downstream boundary layer stability (that is, that tends to keep the boundary layer attached to catalytic surfaces 70 a and 70 b )—for example, an airfoil or similar tapered or non-bluff shape.
Although FIG. 6 shows three injection ports 82 a and three injection ports 82 b , the number and location of injection ports 82 a and 82 b , proximate their respective passages, will be determined according to the desired distribution of reactant stream 6 a and 6 b , heat transfer characteristics of the thermal oxidation and catalytic reduction system, and like parameters, as will be understood by those familiar with such film injection, film cooling and thermal oxidizing and reducing techniques. The present invention also encompasses employing conventional film injection means, as will be understood by those familiar with such meals. Further, reactant channels 76 a and 76 b , and/or injection ports 82 a and 82 b , may be employed with the embodiment of the invention shown in FIG. 3 to supply reactant streams 6 a and 6 b to the catalytic surface 70 c . Reactant streams 6 a and 6 b , and the corresponding devices 76 a , 76 b , 82 a , and 82 b are omitted from FIG. 3 for clarity.
The method according to the present invention will be described in conjunction with the operation of the thermal oxidation and catalytic reduction system, using FIGS. 1, 2 , and 7 for illustration. FIG. 7 illustrates a typical temperature profile of gas stream 4 within the system by providing the relationship of gas stream 4 temperature versus distance x, which is measured spirally along the path of passages 22 and 24 , and, linearly across central chamber 46 . FIG. 7 includes curve A, which represents operation under partial load conditions, and curve B, which represents operation under full load conditions, preferably of an internal combustion engine. Gas stream 4 may be produced, however, by an internal combustion engine (which broadly includes spark and compression ignition engines), an industrial source (which broadly includes burners, turbine combustors, boilers, furnaces, chemical reactors, nitric acid digesters, and the like), or a similar process—preferably operating under oxygen-rich conditions. Gas stream 4 includes oxides of nitrogen, oxygen, and combustible constituents, including hydrocarbons, carbon monoxide, and PM. If stoichiometrically insufficient oxygen is present in gas stream 4 , which may occur especially where the present invention is employed with industrial exhaust gas streams, supplemental oxygen may be added according to known principles, and according to techniques described herein and conventional techniques.
Generally, gas stream 4 flows into spiral inlet passage 22 where it contacts catalytic surface 70 a disposed of the first sidewall 18 , and after oxidation occurs within the thermal oxidation zone, gas stream 4 flows into spiral outlet passage 24 where it contacts catalytic surface 70 b on the convex surface 40 of the second sidewall 20 . The catalytic reduction of the oxides of nitrogen is enhanced by the hydrogen, hydrocarbon, and carbon monoxide constituents of the gas streams 6 a and 6 b , or by those already present in gas stream 4 . Therefore, the operation of the engine (for example, spark timing, injection timing, and valve timing) capable of supplying gas stream 4 may be adjusted to supply an optimum amount of such reactants to optimize NOx reduction.
Specifically, gas stream 4 flows across the catalytic surface 70 a , as is represented in curve portions A 1 and B 1 in FIG. 7, and through matrix 50 , where heat is transferred from the matrix 50 and from the sidewalls to gas stream 4 , as is represented by the curve portions A 2 and B 2 . Gas stream 4 flows from the matrix 50 into the central chamber 46 , preferably where the combustible constituents, including PM and the un-reacted reducing agents, oxidize according to heat transfer and reaction principles described in co-pending application Ser. Nos. 08/922,176 and 09/072,851. The oxidation zone is represented in FIG. 7 as the relatively steeply-sloped curve portions A 3 and B 3 . Gas stream 4 then flows through matrix 52 , in which the gas stream 4 transfers heat to matrix 52 and sidewalls 36 and 38 , as is represented by the curve portions A 4 and B 4 . Gas stream 4 flows into contact with another catalytic surface 70 b disposed along spiral outlet passage 24 , as is represented in curve portions A 5 and B 5 , whereby additional lean-NOx catalysis occurs, especially where reactant stream 6 b is present. In FIG. 7, curve portions A 2 , B 2 , A 4 , and B 4 have a greater slope than corresponding curve portions A 1 , B 1 , A 5 , and B 5 to represent that matrices 50 and 52 increase the overall, local heat transfer coefficient therein.
The relatively smooth temperature profile of the curves A and B, compared with combustion processes corresponding to, for example, premixed flames, demonstrates that the present invention provides relatively long residence times of gas stream 4 within the temperature ranges corresponding to curve portions A 1 , B 1 , A 2 , B 2 , A 4 , B 4 , A 5 , and B 5 . The portions of the system that provide these temperature regions may be employed to optimize the NOx reduction process according to the methods discussed herein utilizing catalytic surfaces 70 a , 70 b , and 70 c . Further, the long residence times at the wide range of temperatures enables the present invention to be employed with a wide variety of other emission control techniques that may require such residence times and temperatures. Further, the present invention, because of the stable oxidation conditions created therein, is well-suited to the wide variations in flow rate and temperature (approximately 70° C. to 600° C.) common to engine exhaust streams.
Under typical partial load operation of a lean-burn internal combustion engine, the temperature of gas stream 4 at the inlet of spiral inlet passage 22 , which is represented as point A 6 , may be approximately 200° C. Under typical full load operation of a lean-burn internal combustion engine, the temperature of gas stream 4 at the inlet of spiral inlet passage 22 , which is represented as point B 6 , may be approximately 400° C. The temperature at which the thermal oxidation reaction begins, which is represented as point A 7 and B 7 , may be approximately 788° C. to 825° C., although these temperatures are only exemplary, and may vary widely.
Referring to FIG. 3 to illustrate another method according to the present invention, the catalytic surface 70 c may be disposed on inlet matrix 50 and catalytic surface 70 c may be disposed on outlet matrix 52 to reduce NOx. In the embodiment shown in FIG. 3, gas stream 4 encounters catalytic surface 70 c in the spiral inlet passage 22 , undergoes oxidation, and encounters catalytic surface 70 c in the spiral outlet passage 24 . Reactant gas streams 6 a and 6 b may be injected into thermal oxidation and catalytic reduction system 10 c proximate catalytic surface 70 c using reactant channels 76 a and 76 b and/or injection ports 82 a and 82 b , as generally described in FIGS. 4, 5 , and 6 .
Thermal oxidation and catalytic reduction system 10 c employing catalytic surface 70 c provides a temperature profile in which curves portion A 1 and A 2 would have substantially the same slope; likewise B 1 and B 2 ; A 4 and A 5 ; and, B 4 and B 5 .
Another method according to the present invention will be described using FIGS. 4 and 5, and it is understood that the present method preferably may be utilized in conjunction with the method described above relating to FIG. 1 . Because the lean-NOx-based catalytic reaction is enhanced by the presence of hydrogen, hydrocarbons and carbon monoxide, reactant gas stream 6 a and 6 b including these constituents may be injected into the spiral passages proximate catalytic surfaces 70 a and 70 b to enhance catalysis. Specifically, reactant gas streams 6 a and 6 b may be directed into reactant channels 76 a and 76 b and through transpiration holes 80 , which may be sized and arranged to provide desired film thickness, cooling characteristics, pressure drop of the reactant stream, local velocity of the reactant stream and gas stream 4 , and like parameters. Also, gas streams 6 a and 6 b may be injected though injection ports 82 a and 82 b , which may be disposed along the desired sidewall. Preferably, injection ports 82 a and 82 b will preferably span substantially along the height of the catalytic surfaces 70 a and 70 b , and inject streams 6 a and 6 b in a uniform profile at low Reynolds number. Regardless of the means used to inject the reactant streams 6 a and 6 b , it is preferred that the Reynolds Number of the flow in the boundary region of catalytic surface 70 a and 70 b is below approximately 1,000 so as to produce a laminar boundary layer to provide a stratified flow.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention. Further, it is understood that the objects of the present invention are not exclusive, as other objects and advantages will be apparent to those skilled in the art. | An integrated oxidation-reduction process whereby a thermal oxidation zone and a NOx reduction zone are incorporated into a single device. A thermal oxidation and catalytic reduction system having a multi-spiral, heat recuperative configuration and including a lean NOx catalytic section disposed in the low-temperature regions is disclosed, as is a corresponding method. The catalyst may be disposed on the oxidizer walls or on a matrix of porous inert media disposed in the spiral passages of the oxidizer. A film-injection technique to selectively provide reactants to the catalyst surface is also disclosed. The catalyst may be limited to a concave portion of a sidewall to diminish boundary layer separation of the reactants. | 8 |
BACKGROUND OF INVENTION
[0001] This invention relates to a pressure pulse generator. Such a pressure pulse generator is usable in particular in the area of drilling, and more specifically in a logging-while-drilling and/or measuring-while-drilling tool.
[0002] In these techniques, drilling is accomplished using a string of drillpipe that terminates in a drilling tool. The logging and/or measuring tools are located near the drilling tool, downhole, in a drillpipe in the string. Logging or measurement data are transmitted to the surface.
[0003] There are various existing methods of achieving this transmission. It may be achieved through electrical signals using the electrical conductors that pass through the drillpipe string. Transmission may also be achieved through acoustic signals transmitted through the drillpipes in the string. These methods permit a relatively high transmission flow rate. But the former of these techniques is relatively expensive to implement and poses problems for the connection of the conductors at the joint between drillpipes in the string. As for the latter, it lacks reliability due to the high degree of noise generated during drilling.
[0004] A conventional data transmission technique uses the drilling fluid as a means of transmitting depth-modulated acoustic waves representative of the logging and/or measurement tool response.
[0005] [0005]FIG. 1 illustrates a drilling device capable of making such logs and/or measurements. This device can be equipped with a pressure pulse generator according to the invention.
[0006] A drilling fluid 1 contained in a tank 14 is injected by a pump 4 from the surface 2 to the inside of a drillpipe string 3 intended to drill into a geological formation 7 . The drilling fluid 1 arrives at a drill bit 5 at the end of the drillpipe string 3 . The drilling fluid 1 exits the drillpipe string 3 and returns to the surface 2 through the space 6 between the drillpipe string 3 and the geological formation 7 . The route of the drilling fluid 1 is illustrated by the arrows.
[0007] One of the drillpipes 3 . 1 in the drillpipe string 3 that is near the drill bit 5 is instrumented. This instrumented drillpipe 3 . 1 contains at least one measurement device 8 intended among other things to evaluate the physical properties of the geological formation, such as its density, porosity, resistivity, etc. This measurement device 8 is part of a logging-while-drilling or LWD tool 13 .
[0008] When this measuring device 8 measures drilling-related parameters such as temperature, pressure, drilling tool orientation, etc., it is part of a measuring-while-drilling or MWD tool.
[0009] The instrumented drillpipe 3 . 1 is generally a drill collar. This is a drillpipe that is heavier than the others. It applies sufficient weight to the drill bit 5 to drill into the geological formation 7 .
[0010] In order to produce a pressure fluctuation in the drilling fluid 1 , and thereby transmit data, a pressure pulse generator 9 is placed in the instrumented drillpipe 3 . 1 just above the area that contains the measurement devices 8 . The pressure pulse generator 9 is part of a telemetry module 12 whose function is to control data transmission between the downhole measurement device 8 and the pressure sensors 10 at the surface. The telemetry module 12 is part of the logging- and/or measurement-while-drilling tool.
[0011] U.S. Pat. No. 3,309,656 describes a rotating pressure pulse generator. Rotating at a constant speed, it partially but repeatedly interrupts the flow of the drilling fluid 1 . The interruptions cause the pressure pulse generator to generate pressure pulses at a carrier frequency that is proportional to the interruption rate. Accelerating or decelerating the generator modulates the phase or the frequency of the pressure waves to transmit the data associated with the measurements made by the measurement device 8 to the surface 2 . Pressure sensors 10 at the surface 2 receive the pressure waves that are propagated in the drilling fluid 1 . Before being demodulated, the acoustic signal representing the pressure waves sensed at the surface is filtered in a processing device 11 to eliminate the noise which is inevitable. The assembly formed by the telemetry module 12 including the pressure pulse generator 9 , the processing device 11 , and the pressure sensors 10 is hereinafter called the “telemetry system.”
[0012] Due to the drilling fluid, which is generally mud, the acoustic signal recovered at the surface is highly attenuated. This limits the performance of pressure pulse telemetry systems.
[0013] Although rotating pressure pulse generators have been improved in the past ten years, they still have weaknesses. U.S. Pat. No. 6,219,301 describes a conventional but more recent pressure pulse generator. Referring to FIGS. 2A and 2B, the pressure pulse generator 9 shown has a stator 20 with several peripheral orifices 21 and a rotor 22 with blades 23 in the form of a cross. The rotor 22 is rotated near the stator 20 by a motor (not shown). The drilling fluid, whose displacement is illustrated by the arrows in the figures, goes through the peripheral orifices 21 of the stator 20 . As the rotor 20 rotates it partially blocks the stator orifices 21 and either significantly restricts the passage of the fluid or else allows it to pass massively. In FIG. 2A, the pressure pulse generator is in the so-called “open” position. The rotor blades 23 do not coincide with the orifices 21 and the flow of fluid through the pressure pulse generator is maximal. A communicating area can be defined for the fluid passage, corresponding to the stator orifices, for example triangles whose sides are approximately 20, 30, and 30 millimeters.
[0014] In FIG. 2B, the pressure pulse generator is in the so-called “closed” position. The rotor blades partially block the orifices 21 of the stator 20 and the fluid flow through the pressure pulse generator is minimal. The pressure pulse generator does not totally prevent the passage of the fluid. Since this fluid serves to lubricate the drilling tool, it is necessary for it to permanently circulate in the drillpipe string so that drilling operations can continue. When the blades 23 of the rotor 22 are opposite the stator orifices 21 , the orifices 21 have an unblocked space 24 . The communicating area for the fluid is the spaces 24 , for example rectangles approximately 28×4 millimeters.
[0015] As the rotor 22 rotates, it generates a fluid flow downstream of the pressure pulse generator in which the pressure falls and rises at the rate of rotation. The pressure pulses generated by the generator rotate at constant speed and are not perfectly sinusoidal. As can be seen in FIG. 4, these pulses are represented with the reference A in FIG. 4. A perfect sinusoid is referenced B. Clipping occurs. Energy is lost in the form of harmonics. These harmonics can interfere with the demodulation of the signal at the surface.
[0016] Inevitably, the fluid contains solid particles or debris. In order to be easily removable, this debris must not be too large because it must pass through the peripheral orifices 21 of the stator 20 . Since larger debris often appears, the drive motor must be powerful enough so that the rotor can grind it up. When the debris is ground up, it can then be discharged. But grinding up this debris may cause wear to the rotor. If the motor power is not sufficient, the pressure pulse generator seizes and clogs, and this can cause the drillpipe string to be clogged.
[0017] In an effort to provide necessary power, pressure pulse generators have been used in combination with turbines. U.S. Pat. No. 5,517,464 describes an integrated modulator and turbine-generator with a turbine impeller coupled by a drive shaft to a modulator rotor downstream from the impeller. The turbine impeller is used to drive the modulator rotor, which is coupled to an alternator. Despite this advancement in downhole energy conservation, there is an ever-increasing need for more power in downhole operations. What is needed is a system that is capable of channeling and/or utilizing the force of fluid flowing through the generator to create additional power.
SUMMARY OF INVENTION
[0018] This invention proposes a pressure pulse generator, also called a turbo-modulator, which remedies the above disadvantages and/or provides further advantages.
[0019] More specifically, the invention proposes a pressure pulse generator that can easily discharge large debris, even in closed position, without grinding it up. The risks of seizing and clogging are considerably reduced. Since the debris can be discharged without being ground up, the pressure pulse generator according to the invention operates with less power. The invention also proposes a pressure pulse generator that generates nearly sinusoidal pressure pulses, so as to increase the efficiency of the telemetry system using such a generator. The invention is provided with a turbine used in combination with the generator to produce downhole power.
[0020] In order to achieve this, this invention is a pressure pulse generator containing a stator with an orifice through which a stream of fluid flows and a rotor also equipped with an orifice. The rotor is intended to turn opposite the stator to allow more or less fluid coming out of the stator orifice to flow. The two orifices present a communicating area for the flow of the fluid stream. This communicating area varies between a maximum and a minimum area depending on the position of the rotor with respect to the stator. The communicating area can vary in basically a sinusoidal manner.
[0021] This communicating area comprises one section located in a central area of the stator-rotor assembly regardless of the position of the rotor with respect to the stator.
[0022] The stator orifice may have a central section located in the central area of the stator and at least one lobe that communicates with the central section. Similarly, the rotor orifice may have a central section located in a central area of the rotor and at least one lobe that communicates with the central section. Advantageously, this central section is preferably circular. The lobe may be part of a sector of a circle.
[0023] In an alternative, the lobe is preferably part of a trapezoid.
[0024] The number of lobes of an orifice contributes to determining the period of the pressure pulses. A particularly interesting shape for at least one of the orifices is preferably a rectangular shape. This rectangle is preferably centered. In this configuration, the pressure pulses are preferably sinusoidal when the rotor rotates preferably at a constant speed. Another particularly interesting shape for at least one of the orifices is a cross shape.
[0025] The amplitude of the pressure pulses is determined by the difference between the maximum and minimum cross-sections.
[0026] With a pulse generator according to the invention, the debris contained in the fluid is carried by the rotor towards the section located in the central area of the stator-rotor assembly.
[0027] This invention also concerns a logging-while-drilling tool that has a pressure pulse generator characterized in this way.
[0028] This invention also concerns a measuring-while-drilling tool that has a pressure pulse generator characterized in this way.
[0029] This invention also concerns a telemetry system that has a pressure pulse generator characterized in this way.
[0030] In at least one aspect, the invention relates to a pressure pulse generator comprising a stator with an orifice intended for the passage of a stream of fluid and a rotor adapted to rotate opposite the stator in order to permit the through flow of fluid to exit the orifice of the stator. The generator is characterized by the fact that the rotor is also equipped with an orifice, both orifices presenting a communicating area for the passage of the stream of fluid. The generator may also include a turbine connected to the rotor.
[0031] In another aspect, the invention relates to a pressure pulse generator comprising a stator with a stator orifice intended for the passage of a stream of fluid, a rotor adapted to rotate opposite the stator for selectively permitting the flow of fluid exiting the orifice of the stator to pass through the rotor, and a turbine operatively connected to the rotor. The rotor equipped with a rotor orifice. The orifices defining a communicating area for the passage of the stream of fluid. The turbine having blades rotatable in response to the flow of fluid through the rotor.
[0032] In another aspect, the invention relates to a pressure pulse generator for a downhole drilling tool. The downhole drilling tool has a fluid passing therethrough. The pressure pulse generator comprises a stator, a rotor and a turbine. The stator has a stator orifice adapted to permit the fluid to flow therethrough and defines a plurality of stator lobes. The rotor is positioned adjacent the stator orifice and has a rotor orifice defining a plurality of rotor lobes of corresponding dimension to the stator lobes. The rotor is adapted to rotate with respect to the stator such that the fluid selectively passes therethrough. The rotor has a channel therethrough and at least one port to permit the fluid to exit the rotor. The turbine is connected to the rotor and has at least one blade. The turbine is rotationally driven by the flow of fluid through the rotor and over the at least one blade whereby power is provided to the downhole tool.
[0033] In yet another aspect, the invention relates to a method of generating power in a downhole tool. The steps include selectively passing a fluid through an orifice of a stator and a corresponding orifice of a rotor in the downhole tool, passing the fluid through the rotor and out one or more exit ports therein and generating rotational energy by passing the fluid from at least one exit port over at least one turbine blade of a turbine operatively connected to the rotor.
[0034] Other aspects will be discernable from the following description.
BRIEF DESCRIPTION OF DRAWINGS
[0035] This invention will be better understood by reading the description of the examples given purely for information and without limitation, referring to the attached drawings, in which:
[0036] [0036]FIG. 1 (already described) shows a drilling device equipped with a logging-and/or measuring-while-drilling tool that can be equipped with a pressure pulse generator according to the invention;
[0037] [0037]FIGS. 2A, 2B (already described) show a prior art pressure pulse generator in the open and closed positions, respectively;
[0038] [0038]FIGS. 3A, 3B show an example of a pressure pulse generator according to the invention in the open and closed positions, respectively;
[0039] [0039]FIG. 4 shows the pressure pulses generated by the pulse generator in FIG. 2 (curve A) and FIG. 3 (curve C), to be compared to a pure sinusoid (curve B);
[0040] [0040]FIGS. 5A, 5B show the front of the stator-rotor assembly of a pressure pulse generator according to the invention in the open and closed positions, respectively;
[0041] [0041]FIG. 6 shows debris lodged in the prior art pressure pulse generator;
[0042] [0042]FIGS. 7A, 7B show the trajectory followed by the debris before being evacuated in a pressure pulse generator according to the invention;
[0043] [0043]FIGS. 8A, 8B show the front of a pressure pulse generator according to the invention with four-lobed orifices, and the shape of the pressure pulses generated;
[0044] [0044]FIGS. 9A, 9B show the front of a pressure pulse generator according to the invention with two sector lobe orifices and the shape of the pressure pulses generated;
[0045] [0045]FIGS. 10A and 10B show the front of a pressure pulse generator according to the invention with optimized two-lobed orifices and the shape of the pressure pulses generated.
[0046] [0046]FIG. 10C shows a three dimensional view of a pressure pulse generator according to the invention.
[0047] [0047]FIGS. 11A, 11B, 11 C and 11 D show the front of a pressure pulse generator according to the invention with three-lobed orifices and the shape of the pressure pulses generated.
[0048] [0048]FIGS. 11E and 11F show a schematic view, partially in cross-section, and a three-dimensional view, respectively, of a pressure pulse generator with a turbine according to the invention.
[0049] In these figures, the identical or similar elements are designated by the same reference characters. For the sake of clarity, the figures are not necessarily to scale.
DETAILED DESCRIPTION
[0050] Referring to FIGS. 3A, 3B, which show a pressure pulse generator according to the invention, this pulse generator is intended to generate pressure pulses in a stream of fluid, which may be a drilling fluid used in a drilling device equipped with a telemetry system like the one in FIG. 1.
[0051] Note that there is a stator 40 that cooperates with a rotor 43 , and the stator 40 -rotor 43 assembly is placed inside a drillpipe 30 in a drillpipe string. The stator 40 has an orifice 41 . The rotor 43 also has an orifice 44 . In order to generate the pressure pulses in the fluid stream, illustrated by the arrows, the fluid enters the pressure pulse generator from the stator 40 side. The fluid passes through the orifice 41 of the stator 40 . When it leaves the orifice 41 of the stator 40 , the fluid goes to the orifice 44 of the rotor 43 , which is opposite the stator 40 . A motor (not shown) drives the rotating rotor 43 around an axis xx′ parallel to the fluid stream.
[0052] When the rotor 43 rotates, it allows more or less fluid from the orifice 41 of the stator 40 to flow. The two orifices 41 , 44 define a communicating area (or intersection) 48 for the passage of the fluid, varying between a minimum and a maximum cross-section. This communicating area 48 includes a section located in a central area of the stator-rotor assembly regardless of the position of the rotor with respect to the stator. The axis xx′ is contained in this communicating area 48 . The central area is an area that includes the center of the rotor-stator assembly. In FIG. 3A, the generator is in the “open” position, in which the communicating area 48 is maximal. In FIG. 3B, the generator is in the “closed” position, in which the communication cross-section 48 is minimal.
[0053] In general, the orifice 41 of the stator 40 includes a central section 42 , i.e., located in a central area of the stator 40 , and at least one lobe 46 that communicates with the central section 42 . This central section 42 and this lobe 46 are visible in FIG. 5B.
[0054] Similarly, the orifice 44 of the rotor 43 includes a central section 45 , i.e., located in a central area of the rotor 43 , and at least one lobe 47 that communicates with the central section 45 . This central section 45 and this lobe 47 are visible in FIG. 5B.
[0055] With such a configuration for the orifices 41 , 44 of the stator 40 and the rotor 43 , the communicating area 48 is achieved for the passage of the fluid with the section located in a central area of the stator-rotor assembly. Orifices 41 , 44 of the rotor and stator can be identical as in FIGS. 3A, 3B, but could have been different shapes.
[0056] In FIGS. 5A, 5B, orifices 41 , 44 are both rectangular and are centered on axis xx′. Then in the center of the rectangle is the central section 42 , 45 and on either side the two lobes 46 , 47 . When the rotor is driven at constant speed, such a configuration makes it possible to generate preferably sinusoidal pressure pulses, referenced C in FIG. 4. There is practically no loss of energy in the form of harmonics. The communicating cross-section varies in preferably a sinusoidal manner. The pressure pulse generator has an increased efficiency and better signal demodulation can be achieved at the surface. This shape of pressure pulses was not possible with the prior art generator illustrated in FIGS. 2A, 2B.
[0057] [0057]FIGS. 5A, 5B schematically show the front view of the rotor 43 of the pressure pulse generator according to the invention and, hidden behind the rotor 43 , the stator 40 . The latter is visible only by its orifice 41 . In this embodiment, the orifices 41 , 44 of the stator 40 and the rotor 43 are preferably identical, rectangular and centered. In FIG. 5A the orifices 41 , 44 are aligned and coincide. The angle of the rotor 43 to the stator 40 is zero modulo Tr. The area for the passage of the stream of fluid, i.e., the communicating surface area between the two orifices 41 , 44 , is maximal and is the same as the surface area of the orifices 41 , 44 . The pressure drop of the stream of fluid through the pressure pulse generator is minimal. The orifices 41 , 44 may have the following dimensions 75 millimeters×20 millimeters but this invention is not limited to a pressure pulse generator whose rotor and stator orifices have these dimensions. Any debris smaller than the aforesaid dimensions can go through the pressure pulse generator.
[0058] In FIG. 5B, the rotor 43 has rotated π/2 modulo π, and now the two orifices 41 , 44 are offset with respect to one another. The lobes 46 , 47 are located on either side of the communicating area.
[0059] The communicating area 48 is minimal and is represented by the intersection between the two orifices 41 , 44 , i.e., the small central white square. The pressure drop of the stream of fluid through the pressure pulse generator is maximal in this case. The dimensions of the communicating area between the two orifices 41 , 44 are preferably 20 millimeters×20 millimeters. The central sections of the orifice 41 of the stator 40 and the orifice 44 of the rotor 43 are represented by the communicating area 48 between the two orifices 41 , 44 . Any debris whose dimensions are smaller than these dimensions can go through the pressure pulse generator. The risk of clogging is much smaller than with the structure in FIG. 2.
[0060] We now refer to FIG. 6, which shows a front view of the stator-rotor assembly of the pressure pulse generator from FIGS. 2A, 2B. This figure helps explain why the risks of clogging are high in this configuration. The orifices 21 of the stator 20 are peripheral and preferably triangular. When the blades 23 of the rotor 22 are rotating, they push the debris 25 into a corner of a triangular orifice 21 of the stator 20 . The debris is stuck between one of the blades 23 of the rotor 22 and one of the corners of an orifice 21 of the stator 20 , as shown in the figure. If the rotor's drive motor is powerful enough so that the debris 25 is ground up and discharged, the pulse generator can continue to function, but the blade 23 of the rotor 22 that acted could be damaged.
[0061] If the motor is not powerful enough to grind up the debris 25 , the pressure pulse generator could go into a de-clogging cycle, with the rotor 22 rotating back and forth several times until the debris 25 is ground up. Increased energy consumption will occur and the rotor 22 is even more likely to be damaged.
[0062] If the debris 25 is still not ground up after a certain period, the situation becomes critical. One solution is to stop everything and pull the string of drillpipe up to the surface in order to access the pressure pulse generator.
[0063] We now refer to FIGS. 7A, 7B, which show why the pressure pulse generator according to the invention makes it possible to easily eliminate debris.
[0064] When debris 49 arrives from a peripheral location, it is carried forward by the rotor 43 , which applies a force F to it. This force F is made up of two orthogonal components F 1 , F 2 . This force F tends to move the debris 49 closer to the central area of the stator-rotor assembly and therefore to push it towards the communicating area between the orifice 41 of the stator 40 and the orifice 44 of the rotor 43 .
[0065] When the pressure pulse generator is in the closed position as in FIG. 7B, the force applied to the debris 49 has only one component F 1 . The debris 49 is located at the communicating area 48 and can be discharged if it has the appropriate dimensions. If it is too large, it can be discharged when the rotor 43 is offset π/2 from the position shown in FIG. 7B and the communicating section 48 between the orifice 41 of the stator 40 and the orifice 44 of the rotor 43 becomes maximal. The risk of clogging is considerably reduced compared to the configuration in FIGS. 2 and 6.
[0066] The pressure pulse generator according to the invention makes it possible to eliminate larger debris because there is only one central fluid passage area regardless of the position of the rotor with respect to the stator. In the prior art, the fluid passage area was always broken up.
[0067] The number of lobes either a rotor or a stator orifice has contributes to determining the period of the pressure pulses generated. A two-lobed configuration of both the stator orifice and the rotor orifice, as in FIG. 6, results in a period π, while a four-lobed configuration as in FIG. 8A results in a period π/2. More generally, a configuration with n lobes (n being a whole number other than zero) in both the rotor orifice and the stator orifice results in a period 2 π/n. If the rotor and stator orifices do not have the same number of lobes, this becomes more complicated.
[0068] It should be noted that for maximum passage areas of equal value, configurations with few lobes (one or two) make it possible to discharge the largest debris.
[0069] [0069]FIG. 8A shows an example of a pressure pulse generator according to the invention in which both the stator and the rotor orifices have the shape of a four-legged cross. These orifices take on the shape of two rectangles offset by π/2. The corners of the rectangles are rounded. These orifices 41 , 44 have a central section 42 , 45 and four lobes 46 , 47 , respectively. In the closed position, as in FIG. 8A, the fluid passage area becomes more and more complex as the number of lobes increases.
[0070] [0070]FIG. 8B shows the appearance of the pressure pulses generated by such a pressure pulse generator. These pulses are preferably sinusoidal and their period is half that shown in FIG. 5. The amplitude of the pressure pulses generated is controlled by the difference between the maximum communication area and the minimum communication area, i.e., the difference between the fluid passage area in the open position and the fluid passage area in the closed position.
[0071] The geometry of the stator and rotor orifices controls the shape of the pressure pulses generated. A centered rectangular shape generates nearly sinusoidal pulses. Other contours are of course possible.
[0072] It is possible, for example, to give the rotor and stator orifices a geometry such as the one illustrated in FIG. 9A. The rotor and stator orifices are preferably identical. Each of the orifices 41 , 44 preferably has a circular central section 42 , 45 with two diametrically opposed sector-shaped lobes 46 , 47 . These sectors are approximately equal to π/2. When the generator is in the closed position, the communicating area at the two orifices 41 , 44 corresponds to the central section 42 . FIG. 9B shows the shape of the pulses generated with a pressure pulse generator of the type in FIG. 9A. This shape is relatively far from a pure sinusoid.
[0073] It is possible to finely adjust the geometry of the orifices 41 , 44 in order on the one hand to optimize the shape of the pressure pulses generated and on the other hand to obtain the largest possible minimum communicating area. FIG. 10A shows such an optimized shape for the orifices 41 , 44 of the stator 40 and the rotor 43 . It is derived from the centered rectangular orifice. Each of the orifices 41 , 44 preferably has a circular central section 42 , 45 and two lobes 46 , 47 that communicate with the central opening 42 , 45 . These two lobes are diametrically opposed and slightly flared and curved.
[0074] [0074]FIG. 10B illustrates the shape of the pulses generated (curve D) by the pressure pulse generator in FIG. 10A, and this shape can be compared to a perfect sinusoid (curve E).
[0075] [0075]FIG. 10C illustrates a three-dimensional view of a pressure pulse generator according to the invention with the configuration in FIG. 10A. The pressure pulse generator is in the open position. The arrows show the direction of fluid flow. The rotor 43 is shown in its entirety because in the preceding figures it was only schematicized by a first section 43 . 1 nearest the stator 40 . This first section 43 . 1 communicates with a second section 43 . 2 in the shape of a funnel to discharge the stream of fluid exiting the rotor. The first section 43 . 1 is made of a particularly strong material because it receives the brunt of the debris mixed into the fluid. The rotor drive motor (not shown) would be placed downstream of the rotor.
[0076] [0076]FIGS. 11A, 11B and 11 C depict another proposed shape for the orifices 51 , 54 of a stator 50 and a rotor 53 , respectively. Each of these figures show the rotor in a different rotational position with respect to the stator. FIG. 11A shows the rotor aligned with the stator at zero degrees rotation, or the “open” position. FIG. 11B shows the rotor in an intermediate position with respect to the stator at the thirty degrees rotation. FIG. 11C shows the rotor in non-alignment with the stator at sixty degrees rotation, or the “closed” position.
[0077] The stator orifice 51 preferably has a circular central opening 52 and three lobes 56 , 57 , 58 that communicate with the central openings 52 . The rotor orifice 54 preferably has a circular central opening 55 and three lobes 66 , 67 , 68 that communicate with the central openings 55 . The lobes are preferably equally spaced and slightly flared and curved. While three, flared lobes are depicted, any number or shape may be used.
[0078] [0078]FIG. 11D illustrates the shape of the pulses generated by the pressure pulse generator of FIGS. 11A, 11B and 11 C. Points H, I and J depict the pressure drop corresponding to the position of the rotor as depicted in FIGS. 11A, 11B and 11 C, respectively.
[0079] Various pressure pulse curves are depicted in FIGS. 8B, 9B, 10 B and 11 D corresponding to the flow of fluid in various rotor/stator configurations. FIGS. 8B, 10B and 11 D depict sinusoidal waves generated by rotation of the rotor at constant speed. FIG. 9B is also rotating at a constant speed, but generates a non-sinusoidal wave based on the geometry of the rotor/stator configuration. However, by varying the speed of the rotor/stator configuration of FIG. 9A over each periodp, a sinusoidal wave may also be generated. In this manner, the variation of speeds and geometries may be manipulated to generate the desired wave. Additionally, the distance between the rotor and stator may be adjusted to provide variations in the pressure pulse amplitude. The closer the rotor is to the stator, the higher the pressure pulse amplitude.
[0080] [0080]FIG. 11E illustrates a pressure pulse generator usable in conjunction with the rotor/stator configurations depicted in FIGS. 11A, 11B and 11 C. FIG. 11E is a cross-sectional view of the generator positioned in a downhole tool, such as the drilling device of FIG. 1. The generator includes a stator 50 having an orifice 51 therethrough, and a rotor 53 positioned adjacent the stator 50 . The arrows show the direction of fluid flow through the stator and rotor 53 . A rotor shaft 55 is operatively connected to the rotor and rotational driven by the generator as indicated by the curved arrow. A turbine 65 is connected to the rotor 53 and drive shaft 55 .
[0081] [0081]FIG. 11F is a three-dimensional view of a rotor 53 and turbine 65 forming part of the generator of FIG. 111E. The rotor 53 includes a first section 53 . 1 , a second section 53 . 2 . The rotor 53 has an orifice 54 therethrough, lobes 66 , 67 , 68 and a central section 55 corresponding to the rotor as depicted more fully in FIGS. 11A, 11B and 11 C.
[0082] Referring still to FIG. 11F, fluid flows through the downhole tool and past the orifice of the stator and the rotor, and into the generator as indicated by the arrow. Fluid flows through the rotor 53 and exits-three ports 69 in the second section 53 . 2 of the generator. Fluid exiting ports 69 in the rotor flows across one or more of blades 80 , 81 , 82 of the turbine 65 . The force of the fluid pushing against the blades rotates the turbine 65 . The rotational force of the blade may then be used to provide power, such as mechanical rotation for the rotor.
[0083] The blades of the turbine are preferably adapted to conform to the force of fluid as it passes through the downhole tool to generate maximum power. As shown in FIG. 11F, the blades are curved to increase the surface contact with the fluid exiting the ports 69 . However, it will be appreciated that one or more of the blades may be straight, angled, or have other geometries adapted to the flow of fluid. Additionally, the exit port 66 may be angled, shaped, configured or otherwise adjusted to direct flow in the desired direction with respect to the blades. The distance between the exit ports 69 and the blades and/or the distance between the rotor and stator may also be adjusted to increase and/or decrease the force of the fluid against the blade. In this manner, the flow of fluid may be optimized to adjust the power generated by the turbine.
[0084] The turbine 65 of FIGS. 11E and 11F is preferably depicted downstream of the rotor 53 . The turbine may be located at various positions along the rotor and in the direction of fluid flow through the generator. Additionally, the generator may be inverted with respect to the flow of fluid and run in a “backwards” position in the downhole tool if the blade inclination is also reversed. The rotor shaft may be positioned uphole or downhole from the stator.
[0085] Referring again to FIG. 1, assume that reference 13 illustrates a logging-while-drilling tool according to the invention and includes the pressure pulse generator 9 according to the invention. It could of course be assumed that reference 13 represents a measuring-while-drilling tool according to the invention.
[0086] Still referring to FIG. 1, the invention also concerns a telemetry system that includes the telemetry module 12 comprising the pressure pulse generator 9 according to the invention 9 , the surface pressure sensors 10 , and the processing device 11 .
[0087] Although several embodiments of this invention have been shown and described in detail, it is understandable that various changes and modifications can be made without going outside the scope of the invention. The rotor and/or the stator could have several orifices, the stator and rotor orifices could be different, and of course the shapes shown are not the only possible shapes. | A pressure pulse generator for a downhole drilling tool is provided. The pressure pulse generator includes a stator with an orifice through which a stream of fluid passes, and a rotor intended to rotate opposite the stator to allow the flow of more or less liquid exiting the orifice of the stator. The rotor is equipped with an orifice, and the two orifices present a communicating area for the passage of the stream of fluid. The rotor is capable of passing fluid therethrough. A turbine with blades rotatable in response to fluid flow through the rotor may also be provided. The turbine is operatively connected to the rotor via a drive shaft. The fluid flow through the rotor may be used to rotate the turbine and provide power usable in the downhole tool. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to deraillers and particularly to a single mount flexible adjustable rear derailler for a bicycle.
2. Description of the Prior Art
Rear derailler units support the roller cage for moving the chain between a number of rear sprockets so as to change the gear ratio of the bicycle. Prior art derailler units have been attached to a supporting bracket attached to the axle and frame of the bicycle and extend generally downwardly from the frame. It has been common for a bicycle to fall to the ground which has resulted in bending of the rear derailler and the bracket of the bicycle. Since the degree of adjustment of the derailler is within certain limits, it has been common for such falls to cause the bending of the bracket and/or the derailler such that the derailler cannot be adjusted to move the chain to all of the sprockets of the bicycle. Since the derailler extends a substantial distance from the support point on the bicycle frame, a substantial lever arm exists and when the bicycle falls over and engages the ground or other obstacle the bracket can be easily bent.
SUMMARY OF THE INVENTION
The present invention provides a novel single point resilient and adjustable mount for a rear derailler wherein the derailler unit is flexibly attached to the support bracket and is spring biased in a first direction so as to hold the derailler under normal conditions in a fixed angular position relative to the bracket. However, if the bicycle falls and/or if the derailler or bracket are subjected to a transverse bending force the derailler can move relative to the bracket so as to prevent bending of the bracket. Means are also provided for adjusting the angular position of the derailler relative to the bracket so that it can be moved outwardly or inwardly relative to the bicycle wheel to the desired position. The result is that the bracket and derailler unit will not be bent when the bicycle falls over and the derailler can be easily adjusted by the adjustment mechanism associated with the resilient one point support.
Other objects, features and advantages of the invention will be readily apparent from the following description of certain preferred embodiments thereof taken in conjunction with the accompanying drawings although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure and in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially cut-away plan view of the rear derailler unit of the invention;
FIG. 2 is a sectional view through the derailler unit;
FIG. 3 is a sectional view through the derailler unit;
FIG. 4 is a detailed view illustrating the derailler unit in a deflected position relative to the bracket;
FIG. 5 is a perspective view of the novel link of the derailler;
FIG. 6 is a side view of a modification; and
FIG. 7 is an enlarged detail view of the out stop.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates in partial cut-away a rear bicycle wheel 25 mounted to the bicycle frame 10 by an axle 12, a washer 14 and a nut 13 receivable on the threaded axle 12. A rear derailler mounting bracket 15 is of conventional type and has a slot receivable about the axle 12 and under the washer 14 and a bolt 16 receivable in the channel of the frame so as to prevent the bracket 15 from rotating relative to the frame. The rear derailler unit 27 is generally channel shaped and has sides 36 and 29 as shown in FIG. 3, and has its upper end 47 with a downwardly extending side 48 as best shown in FIG. 2 and FIG. 4. As shown in FIG. 2, the mounting bracket 15 has an opening through which a boss 42 of a coupling member 39 extends. A spring washer 43 is received in a groove on the boss 42 so as to lock the coupling member 39 to the supporting bracket 15. A pivot shaft 38 extends through the channel walls 29 and 36 of the derailler channel member 27 and through the coupling 39 as shown in FIG. 2, so that the derailler channel member 27 is pivotally attached to the coupling member 39. The coupling member 39 has a bottom portion 41 which engages the bracket 15 and has an outwardly extending portion 49 which is formed with a threaded opening through which a bolt 51 is threadedly received. A spring 54 is mounted about the bolt 51 between the portion 49 of the coupling member 39 and the inner wall of the derailler channel member 27 as shown in FIG. 2. An opening 53 is formed in the channel member and the head 52 of the bolt 51 is available externally of the channel member 27.
The opening 53 in the member 27 is small enough that the threaded portion of the bolt 51 can pass therethrough but the head of 52 of the bolt 51 cannot pass through the opening 53.
A roller cage 28 is supported from the derailler channel member 27 by means including a transverse shaft 61 which passes through openings 66 and 67 in a first link 62 shown in FIG. 5 which has its opposite ends spaced closer together than the portions 66 and 67 and formed with portions 68 and 69 with openings 71 and 72 through which a shaft 63 extends to pivotally support a link 73. The other end of link 73 is attached by pin 74 to a link 76 which is also pivotally supported to a portion of the channel member 27 by pivot pin 77 as shown in FIG. 2. The roller cage 28 is supported from the link 76 by means of a shaft 31 and spring 97 which are connected to a bracket 96 mounted on the link 76. The actuating cable 29 of the bicycle is attached to a supporting bracket 97 on the member 27 and engages and is attached by bolt 81 to an actuating link 78 which has one end supported on pivot pin 77 which passes through the member 27 and has its opposite end formed with a coupling member 79 upon which screw 81 is attached so as to lock the cable 29 to the member 79. A spring 87 is mounted between the link 78 and the link 76 and a stop 99 mounted on link 78 engages link 76 so as to limit in a first direction the angular movement between the links 78 and 76 but so as to allow flexible motion in the opposite direction. The spring 87 engages a projection 86 on the member 27 and its opposite end engages link 76.
The spring 87 and the links 78 and 76 are coupled in the fashion disclosed in U.S. Pat. No. 3,903,751, such that if the cable is moved to the left relative to FIGS. 2 and 3 so as to shift the roller cage at a time when the bicycle is not moving the link 78 can move relative to link 76 without breaking or stretching the cable. However, whenever the bicycle starts to move after such adjustment of the cable or if the bicycle is moving when the cable is adjusted shifting will immediately occur.
A limit screw 88 is threadedly received in a bracket 101 on member 27 and is engageable with a stop 102 on member 62 to adjust the limit of the outer position of the derailler. A second limit screw 104 has a head which is accessible through an opening 106 in the member 27 and passes through a bracket on member 27 and engages the link 76 to adjust the inward position of the derailler unit.
In operation, the bracket 15 and derailler member 27 are mounted on the bicycle axle and the nut 13 is tightened. The bolt 51 is adjusted by turning the head 52 such that the angular position between the member 27 and the coupling member 39 is as desired. It is to be realized that as the bolt 51 is tightened the head of the screw 52 engages the member 27 and pushes it clockwise relative to FIG. 2. Alternatively, as the bolt 51 is loosened, the head of the bolt 52 moves to the left relative to FIG. 2 allowing the member 27 to move counterclockwise due to the action of the spring 54. When the correct adjustment is made, the limit bolts 104 and 88 are adjusted to set the inner and outer limits of the derailler unit and the mechanism is ready for use. In the event the bicycle falls and the derailler member 27 engages the ground or other obstacle rather than applying a bending force to the bracket 15, the member 27 can move about the pivot shaft 38 as shown in FIG. 4, thus softening and reducing the bending torque applied to the bracket 15. After the impact has been made with the ground, the spring 54 will cause the member 27 to return to the initially adjusted position and the derailler will be in the original operating condition without the bracket or derailler unit having been bent. In prior art devices, when the bracket 15 has been bent and without the flexible coupling between a link 39 and the member 27 according to the invention, it has been necessary to remove the entire unit from the bicycle so as to restraighten the bracket because when the bracket is bent it can prevent the derailler from being adjusted within its operating limits as the range of adjustment may not be such as to compensate for the bent bracket.
FIGS. 6 and 7 illustrate an embodiment in which stop screws 88 and 104, opening 106 and bracket 101 are eliminated, and an extrusion 181 in the side of member 27 replaces the stop screw 88 and is placed in a proper position relative to stop 102, to provide an out limit. Thus is provided a predetermined excursion of the shifting mechanism to accommodate the distance required to shift through all gears, as well as the overtravel required to accommodate worn chain, gear, etc. The fully retracted position is limited by member 62 being seated in 27.
Since the majority of bicycles have fairly constant distance from rear drop out to the rear cluster and all five gear clusters have the same distance high gear to low gear, the real need for adjustment is to correct for the angular irregularities of the surface to which the derailler is mounted. So, if the single screw is adjusted to properly place the shifting mechanism relative to cluster gear, this also corrects for the angular drop out plate or wheel mount bracket which occurs in the production lines of bicycle manufacturers and truly a single screw adjustment is obtained.
It is seen that the present invention provides a novel single point resilient and adjustable mount for a rear derailler and although it has been described with respect to preferred embodiments, it should not be so limited as changes and modifications can be made therein which are within the full intended scope of the invention as defined by the appended claims. | A single point resilient and adjustable mount for a derailler which allows the rear derailler unit which supports and moves the roller cage to be flexibly and adjustably attached to the holding bracket attached to the axle and frame of the bicycle and which has a single adjustment for allowing the derailler unit to be angularly moved relative to the bracket so as to prevent bending of the bracket and derailler and easy and simple adjustment of the derailler. | 1 |
This application is a divisional of application Ser. No. 08/490,329, filed Jun. 14, 1995 now U.S. Pat. No. 5,628,143.
FIELD OF THE INVENTION
This invention relates to the field of devices designed to exterminate rodents by poisoning.
DESCRIPTION OF THE PRIOR ART
The present invention represents an improvement upon the devices disclosed in my prior U.S. Pat. No. 5,038,516 and to better enable the method claimed in the said patent to be processed with greater safety. Also, the present invention is a divisional of my prior application which has now been issued as U.S. Pat. No. 5,628,143.
In addition to what is disclosed in my said prior patent, the latter described certain prior art devices and other devices may be seen in other patents cited as references on the cover of said patent.
While the dispenser disclosed in my prior U.S. Pat. No. 5,038,516 is effective to enable the method claimed therein to be practiced, I have found that improvements may be made to render the dispenser both more effective in accomplishing its objective and safer from the standpoint of preventing any of the poison to be accessed by children or domestic pets.
SUMMARY OF THE INVENTION
The present invention improves its effectiveness by disposing its feeder troughs in an internal diversion from the passageway extending directly between the entrance and exit openings, thereby preventing the rodent from simply rushing through the passageway by entering the access hole and exiting from the opposite end of the passageway after simply giving a quick sniff or tasting a minimal amount of a dry or liquid poison substance. The troughs thus are disposed on the sides of the container which are opposite a wall defining the passage between the entrance and exit openings. A further passage is provided extending at a right angle centrally from the main passage, the end of which further passage is then split into two side passages extending to the forwardly facing troughs of the dispensers. In plan view, the passage configuration would be that of an "H", with the right hand vertical comprising the passage between the entrance and exit to the box. This requires that the rodent make a further entry into the box in order to access one or both of the poison substances with less likelihood that the rodent will simply taste and scamper out instead of stopping to consume a sufficient amount of the poison substance to cause its demise. A further advantage of this structure is that children are prevented from putting fingers or sticks into the box to pull out any of the poison substances to taste or feed to domestic pets.
A further improvement in the dispenser of the present invention over that of my prior patent lies in the fact that the dry food may no longer need be dispensed into the trough by a hopper carrying the food in granulated or pellet form, but the dry food is formed in large cylindrical or rectangular blocks having axial holes through which may be passed a rod extending vertically up from the trough. This type of dispenser prevents poison pellets from being shaken out of the box through the main passageway where the pellets may be picked up and tasted or eaten by children or domestic pets. With these orificed cylindrical blocks, when the bottom block is eaten by a rodent, the block above it slides down the vertical element to seat in the trough as a replacement for the consumed lower block. These blocks cannot fall out through the passageway in contrast to pellets which may inadvertently be discharged through the access or exit openings at the ends of the passageway, particularly when the dispenser box is being carried and the dry food dispenser contains pellets.
It is also a feature of the present invention to provide a liquid dispenser having a valve which is normally closed when the container is inverted, thereby preventing the escape of any fluid. The valve, however, is opened by a vertically extending axial projection in the trough which, when the liquid dispenser is inverted and seated in the container, allows fluid to flow into the liquid dispensing trough. When the liquid dispensing trough has been filled, the liquid therein prevents further discharge from the container, until the liquid level is lowered by the rodents drinking up the liquid bait.
It is also a feature of the present invention to provide special locking means at the top of the housing which may be divided along a transverse vertical plane with the forward part of the housing being hinged at the bottom to the after part of the housing.
The locking mechanism comprises at least one flexible element which is permanently seated inside one of the two parts of the housing and extends across the plane of division of the housing to the other part, at or near the end of which on each side is a vertically extending base coaxial with the other base. The latter includes a receptable in line with the flexible element, with the receptacle being provided with registering opposed orifices, each being adapted to receive one of the bosses of the element when inserted in the orifice. The orifices are spaced apart by a distance of at least as great as the combined distance between the outwardly projecting ends of the element and the thickness of the element. The element is biased upwardly to insert the upper boss in the upper orifice, thereby preventing opening of the housing. When a pin-type key of proper length is pushed down through an access hole in the upper wall of the housing and down through the upper orifice of the receptacle, the upper boss of the element is forced out of the latter orifice so that the element may be withdrawn from the receptacle and the housing opened. However, if a pin of improper length is inserted through the upper orifice, either it will not force the upper boss out of that orifice, or it will push the lower boss into the lower orifice, thereby preventing withdrawal of the flexible element from the receptacle, and hence maintaining the two parts of the housing in locked condition. By increasing the number of locking elements provided, the chance of opening the locking mechanism by inserting separate pin-like members is further diminished. Ideally, providing three of the described flexible elements with a key comprised of a metal plate from which extend, at right angles and, properly spaced apart, three pins of the exact length to move all three elements into release position, would be most effective. Thereby, only a person with a proper service key may unlock the front part of the housing from the rear part.
It is also a feature of the present invention to provide holes in the back walls of the housing through which bolts or other elements may be passed in order to secure the housing to a vertical surface or member such as a wall, fence post or fence itself.
From a consideration of the various features of the invention as summarized above, it may be seen that a most effective poison bait dispenser is produced which lends itself to easy installation and servicing, yet cannot be opened except by the use of destructive force, the proper key in hands of the service man. Inadvertent spillage of solid bait of the pellet-type is prevented, thereby avoiding the possibility of consumption by children or domestic pets.
DESCRIPTION OF THE DRAWINGS
In the accompanying drawings,
FIG. 1 is a perspective view of the preferred embodiment of the invention with the housing in closed condition.
FIG. 2 is an enlarged perspective similar to FIG. 1 except that it shows the housing in opened-up condition with liquid and solid dispensers seated in their dispensing positions.
FIG. 3 is a perspective view similar to that of FIG. 2 but showing the liquid and solid dispensers removed from inside the housing.
FIG. 4 is a sectional view partly broken away and enlarged, taken along the line 4--4 of FIG. 1.
FIG. 5 is a an enlarged detail of the locking mechanism shown in the upper portion of FIG. 4.
FIG. 5A is similar to FIG. 5 but illustrates a variant of the locking arrangement of the present invention.
FIG. 6 is a perspective view of a two pin key shown in end view in FIG. 5.
FIG. 7 is an enlarged detail of an embodiment of the invention having a special dispensing cap on the lower end of the liquid dispenser shown in FIG. 2 and seated in the liquid trough shown in FIG. 3.
FIG. 8 is a perspective view similar to FIG. 2 but showing a different type of solid bait dispenser.
FIG. 9 is a partial perspective view of an opened housing in which only a single liquid poison dispenser is provided.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1, 2 and 3, the poison bait dispenser of the present invention comprises a housing 10 formed of a front portion 10a and a rear portion 10b. The front and rear portions 10a and 10b are hinged together at 12 (FIG. 4), at least partially along their bottom edges 10a' and 10b'.
The front portion 10a is formed with an arcuate wall 14 convexly curved with a center section 16 which is internally reinforced by ribs 18 and flanked by a pair of arcuately curved side sections 20 and 22 The rear portion 10b against which the forward portion 10a interfits may be formed of a bottom wall 24, a rear wall 26, a pair of oppositely facing spaced apart side walls 28 and 30, and a top wall 32. The lower area of wall 28 has an opening 34 and the lower area of the wall 30 has a similar opening 36. At the top of the front portion 10a, there is provided internally one half of the locking mechanism 38, hereafter to be described, while the underside of the top wall 32 of the rear portion 10b is provided the other half 40 of this locking mechanism.
As may best be seen from FIG. 3, the bottom wall 24 of the rear section 10b may be molded with a plurality of upstanding walls 42a, 42b, 44a and 44b. The walls 42a and 42b may be parallel with, and spaced from, the rear wall 26 by a sufficient distance to clear the openings 34 and 36 in the side walls 28 and 30, respectively. The wall 42a extends inwardly toward the wall 42b from side wall 28, and wall 42b extends inwardly toward wall 42a from side wall 30. The inner vertical edges 42a' and 42b' are spaced from each other to provide access to and from the resulting passage 46 extending between the openings 34 and 36 in the side walls 28 and 30, respectively, and partially defined by the walls 26, 42a and 42b. A second passage 48 parallel to passage 46 is defined by the forward sections 44a' and 44b' of the walls 44a and 44b, respectively, and the inner faces of the center section 16 and side sections 20, 22 comprising the hinged front portion 10a of the dispenser, when that portion 10a is closed against the rear portion 10b.
Desirably, the walls 42a and 42b are centrally notched at 41a, 41b, respectively, where inverted plastic bottled-shaped containers 50, 52 are employed to carry and dispense poisonous pellets 54 and liquid poison 56 to the respective troughs 58 and 60 defined by the walls 42a, 44a, and 44a' in the case of the trough 58, and the walls 42b, 44b and 44b' for the trough 60, as may best be seen in FIGS. 2 and 4. The plastic bottles 50 and 52 are configured to seat in the notches 41a and 41b, respectively.
Because the dispenser 10, when fully set up for its intended purpose, contains both liquid and solid poisons which should not be allowed to be accessed by, or fall into the hands of, children, or be eaten by domestic pets, provision is made for securing the rear wall 26 to some type of fixed vertical surface or support (not shown ). A plurality of orifices 62 are provided in the back wall 60 to enable the dispenser 10 to be secured to such fixed vertical surface or support against removal.
In addition, the present invention utilizes a special locking combination 38, 40 to secure the hinged forward portion 10a to the rear portion 10b. This locking system may best be understood from a consideration of FIGS. 4, 5 and 6 of the drawings. The lock half 38 comprises a thickened wall portion 66 having a slotting 68 into which is fixedly secured by adhesive or other means (not shown) a flexible element 70 which extends across the plane 64 and is provided at, or near its, outer terminus with a pair of co-axially oppositely extending bosses 72, 74. The lock half 40 is provided with a transversely extending lower plate 76 having an orifice 78 and an upper hood 80 which is spaced from the plate 76 by a distance just slightly more than the distance between the outer end of the bosses 72, 74. The hood 80 is also orificed at 82 coaxially with the orifice 78 in the plate 76. Each of the orifices 78 and 82 is dimensioned slideably to receive the bosses 74 and 72, respectively. The orifice 82 is accessible through a registering orifice 84 in the top wall 32 of the rear portion 10b. Desirably, a plurality of the flexible elements 70 and combinations of the plate 76 and hood 80 should be employed to prevent a person from inserting some type of pin through a single orifice 84 in an effort to manipulate the flexible element 70 to release it from a locking disposition in which one of it bosses 72 or 74 is seated in either orifice 82 or orifice 78, respectively. As may be appreciated, in order to effect a release of the element 70 from the locking half 40, the bosses 72 and 74 must be so disposed that boss 72 is forced downwardly and out of the orifice 82, but not so far that boss 74 is pushed into orifice 78. This disposition is shown in FIG. 5 and is accomplished by providing a key 86 having a plate or block 88 below which extend downwardly one or more pins 90 of the exact length required to place the element 70 in releasing disposition, as shown in FIG. 5. When the element 70 is placed in the releasing disposition referred to above, the front portion 10a of the housing 10 may be pivoted forwardly about the axis of the hinge 12 to depose the front portion 10a in the position shown in FIGS. 2, 3, 8 and 9.
The principle utilized in this locking mechanism may be employed in a slightly different arrangement wherein the upper plate 80' is provided with a recess 82' of a configuration to accommodate a preselected configuration of the coaligned upper boss 72', instead of the orifice 82 through the plate 80, also to receive the key pin 90 to enable the boss 72 to be pushed out of the orifice 82. In the alternate embodiment, the upper boss 72' may be of a different configuration biased into the recess 82', but may be displaced therefrom by pushing a rigid elongated element 90' through a key orifice 84 in either the first or second housing members 10a', 10b' (preferably through 10b' as shown in FIG. 5A), but not so far as to cause its lower boss to enter the recess 78' in the lower plate 81.
In the embodiment of the invention shown in FIG. 2, pellets 54 are deposited from the bottle container 50 into the trough 58 in the manner of a hopper. The liquid poison, however, reaches the trough 60 through a bottle-type container which is provided with a valve cap 92 shown in detail in FIG. 7 and actuated by a vertical element 94 extending upwardly from the floor 24 of the rear portion 10b of the housing 10. The cap 92 may comprise an overhung section 96 of a rubber or resilient material which supports by a resilient cylindrical wall 98, a transverse closure member 100. The latter member is normally held into closed position against the inner end 102 of the liquid bottle container 52. However, when the container 52 is inverted so that a cap orifice may be placed over the pin 94 to permit the latter to press against the transverse closure member 100 and stretch the cylindrical wall 98, fluid may pass around the periphery of the transverse closure member and down through channel orifices and into the trough 60.
In the embodiment of the invention shown in FIG. 8, in lieu of the hopper-type dispenser 50, pellets 54, there is substituted blocks of solid bait which are actually orificed at 110 to be slipped onto a vertical element 112 extending upwardly from that part of the floor 24 in the trough 58 of the lowermost block 108 is consumed, the upper block or blocks 108 slide down the vertical element into the trough as replacement for the consumed poison block.
In the embodiment of the invention shown in FIG. 9, a single liquid dispenser 114 is provided and only a single entry orifice (not shown) would be made in the lower portion of the side wall 30'.
In use, the housing 10 as shown in FIG. 1 is opened by inserting the pins 90 of the key 86 into the orifices 84 in the top 32 of the rear portion 10b of the housing. Because the pins 90 are of the proper length, when pushed down into the orifices 82, they will force the elements 70 into releasing position so that the front portion 10a of the housing may be pulled away from the rear portion 10b about the bottom hinge 12, thereby to open the housing 10 to the disposition shown in FIG. 3. Bottle containers 50 and 52 are then inserted and seated on the notches 41a and 41b on the walls 42a and 42b, respectively to assume the positions shown in FIG. 2. This will result in pellets 54 dropping down out of a container 50 into the trough 58, and fluid poison 56 flowing out of the bottle container 52 and into the trough 60, through the opening of the transverse closure member 100 being pressed against the vertical element 94, thereby allowing the fluid bait to pass into the trough 60 through the cap orifices 104.
Either before or after the bottle containers 50, 52 have been inserted and seated, the back wall 26 of the rear portion of the housing is placed against a barn, garage or other wall, or against a wide fence post and screwed or bolted thereto by screws 61. After being thus secured, and the bottle containers 50 and 52 have been mounted in the notches 41a and 41b in the walls 42a and 42b, respectively, to fill the troughs 58 and 60, the front portion 10a of the housing 10 may then be swung up and back about the hinge 12 to close against the rear portion 10b of the housing 10, where it is locked by the locking mechanisms 38 and 40.
When thus disposed, a rodent (not shown) may enter the housing through either opening 34 or 36 and proceed in the passage 46 to the center where it would be likely to move in between the troughs 58 and 60 to the front passage 48. There the rodent may access either of the troughs for pellets 54 or liquid poison 56. If the rodents' consumption of one or both poisons should not cause its immediate demise within the housing 10, it should do so shortly after the rodent has left the housing by one of the openings 34 or 36.
Because of the disposition of the troughs on the forward sides of the walls 42a and 42b, it is not possible for a small child to insert his hand and arm into the housing openings 34 or 36 to reach either trough with the liquid or solid poison.
Also, because of the nature and effectiveness of the locking mechanism, the latter can only be opened by a key 86 having pins 90 of an exact length.
The dispenser of the present invention, therefore, will be found to be one which can be inexpensively manufactured, light in weight, easy to set up and install and most effective in killing rodents. | A poison bait dispenser for rodents which may dispense liquid or solid poisoned bait, or both, comprising a housing having a front member and a rear member hinged and securable together and defining a space in which is provided a first pathway between two opposite side openings, which pathway is defined by the back wall of the rear member and partial walls spaced from the back wall. The partial walls provide support for the poison bait dispensers and also front trough walls defining a second pathway extending between the troughs. The second pathway is connected to the first pathway between the troughs. Solid bait may be dispensed as blocks slideable down into one trough on a vertical axis. A special cap dispensing member may be provided for the liquid bait. Special locking arrangement with pin keys of preselected lengths prevents passable opening of the dispenser by unauthorized persons. | 0 |
TECHNICAL FIELD OF THE INVENTION
The present invention is generally directed towards an apparatus to allow a user to safely obtain a fluid sample from oil-filled electrical equipment.
BACKGROUND ART OF THE INVENTION
Large industrial electrical equipment, such as oil-filled pad mounted transformers, load tap changers, and the like, contain contacts and other parts which can wear out over time. Since these parts are located inside an oil-filled tank, it is very difficult to visually inspect them. Instead, dissolved gas analysis is often used to measure the level of “fault gases” in the oil. The level of fault gases may be used to estimate the condition of the equipment. However, dissolved gas analysis requires an oil sample to be taken from the transformer tank. Typically, the oil sample would be taken from a valve located on the tank within the transformer cabinet. Because the valve is inside the cabinet, alongside exposed electrical contacts, the transformer would need to be de-energized before the sample was taken to avoid the risk of injury or death to the person taking the sample. De-energizing a transformer is costly. What is needed is an apparatus that will allow a user to safely obtain an oil sample from electrical equipment without having to de-energize the equipment. The apparatus is preferably also tamper resistant.
SUMMARY
Problems with prior art oil sampling are solved by providing an improved electrical equipment housing which includes an oil sample valve and a gas port assembly which are contained within the electrical equipment housing, and are separated from electrical contacts and may be accessed without exposure to the electrical contacts. The improved electrical equipment housing preferably comprises: a tank containing electrical equipment and a liquid; electrical contacts extending through a wall of the tank; a liquid sample port; an enclosure surrounding the electrical contacts and the liquid sample port; a cavity containing the liquid sample port, wherein the cavity is configured to substantially physically isolate the liquid sample port from the electrical contacts; and an opening in the enclosure configured to provide access to the cavity while maintaining substantial physical isolation of the liquid sample port from the electrical contacts.
In one embodiment, the electrical equipment housing further comprises a lockable cover configured to selectively close the opening.
In another embodiment, the electrical equipment housing further comprises a second opening, the second opening allowing access to the electrical contacts.
In another embodiment, the electrical equipment housing further comprises a gas and a remote gas port contained in the cavity.
Also provided is a remote sample kit for an electrical equipment housing comprising: a drain connector configured to connect to a drain valve of a tank; a remote sample port; a sample line connecting the drain connector to the remote sample port; and a remote housing containing the remote sample port and configured to attach to a wall of the electrical equipment housing.
In another embodiment, the remote sample kit further comprises: a remote gas port; a gas connector configured to connect to a gas port of the tank; and a gas line connecting the remote gas port to the gas connector.
In another embodiment, the remote housing also contains the remote gas port.
In another embodiment, the remote sample kit further comprises an opening in the remote housing to allow access to the remote sample port through the wall of the electrical equipment housing.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further advantages thereof, reference is now made to the following Description of the Preferred Embodiments taken in conjunction with the accompanying Drawings in which:
FIG. 1 is a perspective view of a pad-mounted transformer with an embodiment of the present invention;
FIG. 2A is a view of a typical transformer cabinet.
FIG. 2B is a view of a typical transformer cabinet including an embodiment of the present invention;
FIG. 3A is a detailed view of a gas port assembly.
FIG. 3B is a detailed view of a gas port assembly configured for use in an embodiment of the present invention.
FIG. 4A is a detailed view of a drain valve.
FIG. 4B is a detailed view of a drain valve configured for use in an embodiment of the present invention.
FIG. 5 is a detailed view of a remote collection station for use in an embodiment of the present invention.
FIG. 6A is view of a transformer cabinet with a remote collection station in a closed position.
FIG. 6B is view of a transformer cabinet with a remote collection station in an open position.
FIG. 7 is a back view of a remote collection station.
FIG. 8 is a perspective rear view of a kit for adding a remote collection station to an electrical equipment housing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 , reference number 10 indicates a housing for electrical equipment used in electricity distribution. The equipment shown and discussed herein is a pad-mounted transformer, although the disclosed invention may be used in connection with other electrical equipment. Transformer 10 comprises a cabinet 12 , a tank 14 , and radiator 16 . Cabinet 12 comprises main doors 102 and a remote collection station 50 . Main doors 102 and remote collection station 50 are shown in a closed configuration. In this configuration, main doors 102 and remote collection station 50 are preferably locked to restrict access to components (shown in FIG. 2 ) within cabinet 12 .
FIG. 2A shows the inside of cabinet 12 without the improvements of the disclosed invention. A number of items are attached to a back wall 202 of transformer cabinet 12 , including low-voltage contacts 204 , high voltage contacts 206 , and a tank thermometer 208 . Low-voltage contacts 204 and high voltage contacts 206 are conductively connected to electrical equipment such as transformer windings (not shown) in tank 14 . Near a top of back wall 202 is a gas port assembly 30 (discussed in connection with FIGS. 3A and 3B ). Near the bottom of back wall 202 is a drain valve 40 (discussed in connection with FIGS. 4A and 4B ).
FIG. 2B shows the inside of cabinet 12 including an embodiment of the present invention. Cabinet 12 further comprises remote collection station 50 , a gas line 222 , and an oil sample line 224 . Gas line 222 and oil sample line 224 are discussed in more detail below. To minimize clutter and the risk of hose damage, gas line 222 and oil sample line 224 are preferably secured to back wall 202 by clips, zip ties, or the like.
FIG. 3A is a closer view of a typical gas port assembly 30 found in transformer cabinets. Gas port assembly 30 includes a pressure-vacuum gauge 302 . Pressure-vacuum gauge 302 indicates the pressure within tank 14 . To avoid contamination, tank 14 must have a positive internal pressure before drain valve 40 may be opened to obtain a sample. Gas port assembly 30 also comprises a pressure-relief valve 304 which vents gasses from inside tank 14 if the internal pressure exceeds a predetermined level.
FIG. 3B is a closer view of gas port assembly 30 configured for use in an embodiment of the disclosed invention. A T-junction 322 is installed between pressure-relief valve 304 and back wall 202 . T-junction 322 includes a first hose barb 324 . Gas line 222 attaches at one end to the first hose barb 324 and at an opposite end to a remote gas assembly 502 (discussed below in connection with FIG. 5 ). Pressure-vacuum gauge 302 in FIG. 3A is shown in FIG. 3B as removed and replaced by T-junction 322 with first hose barb 324 attached. Alternatively, first hose barb 324 could replace pressure-relief valve 304 . First hose barb 324 is preferably a ¼″ hose barb. Gas line 222 may be secured to first hose barb 324 using a hose clamp (not shown). Alternatively to using a hose barb and hose clamp, other methods of connecting gas line 222 to the gas port assembly 30 are known and may be used. Alternatively to connecting the gas line 222 to gas port assembly 30 , a dedicated port (not shown) for connecting the gas line 222 may be provided during construction of tank 14 or may be added to tank 14 after construction by defining a hole in tank 14 and adding a threaded adaptor, hose barb, or the like to tank 14 . Alternative gas line connection ports should be located sufficiently high on tank 14 so that the connection ports are above the oil level in tank 14 .
FIG. 4A is a closer view of a typical drain valve 40 . Drain valve 40 comprises a control handle 402 configured to open and close drain valve 40 . Drain valve 40 also comprises a sample device 404 . Sample device 404 allows a technician to remove an oil sample from tank 14 . Typically, the sample is removed using a syringe (not shown).
FIG. 4B is a closer view of a drain valve 40 configured for use in the present invention. In FIG. 4B , drain plug 426 has been removed, and second hose barb 424 is installed in its place, along with a reducer 428 . Alternatively, sample device 404 may be removed and replaced with a second hose barb 424 . An oil sample line 224 (see FIG. 2B ) preferably connects at one end to drain valve 40 via second hose barb 424 and at an opposite end to a remote sample assembly 540 (discussed below in connection with FIG. 5 ). Second hose barb 424 is preferably a ⅝″ hose barb. Oil sample line 224 may be secured to second hose barb 424 using a hose clamp (not shown). Alternatively to using a hose barb and hose clamp, many other methods of connecting oil sample line 224 to drain valve 40 are known and may be used. Alternatively to connecting oil sample line 224 to drain valve 40 , a dedicated port (not shown) for connecting the oil sample line 224 may be provided during construction of tank 14 or may be added to tank 14 after construction by defining a hole in tank 14 and adding a threaded adaptor (not shown), hose barb, or the like to tank 14 . The alternative oil sample line connector ports, if used, are preferably located near the bottom of tank 14 .
FIG. 5 shows a closer view of remote collection station 50 . Remote collection station 50 comprises a mounting flange 502 which is configured to attach to a side wall 602 of cabinet 12 . Mounting flange 502 preferably comprises steel sheet metal. Remote collection station 50 comprises a cover 512 that is attached to mounting flange 502 by hinge 514 . Preferably, hinge 514 is a type that is tamper-resistant when closed. A lock receiver 522 is permanently attached to mounting flange 502 . Lock receiver 522 is configured to protrude through a lock receiver hole 524 defined in cover 512 . Once cover 512 is closed, lock receiver 522 may be twisted 90 degrees to hold cover 512 in a closed position. Remote collection station 50 may be secured by inserting a lock 604 (shown in FIG. 6A ) through lock receiver 522 when cover 512 is in a closed position. Remote collection station 50 also preferably includes a weather shield 558 , attached to mounting flange 502 . Whether shield 558 is configured to at least partially shield remote collection station 50 from precipitation. Weather shield 558 is preferably integrally constructed from the same piece of metal as mounting flange 502 .
Inside remote collection station 50 are remote gas assembly 530 and remote sample assembly 540 . Remote gas assembly 530 preferably comprises a pressure gauge 532 . Pressure gauge 532 allows a user to easily verify that a positive pressure exists in tank 14 before taking an oil sample. Remote gas assembly 530 also preferably comprises an inlet port 534 , through which a user may apply a gas (not shown), such as nitrogen or dry air, to increase the pressure in tank 14 , if necessary. Remote sample assembly 540 comprises a shutoff valve (not shown) which is operated by valve handle 542 . Remote sample assembly 540 also comprises remote sample device 544 . Remote sample device 544 is preferably a typical sample device as is known in the prior art. However, remote sample device 544 may be any device capable of allowing a user to remove an oil sample from tank 14 without excessive contamination of the sample.
Back wall 550 and a remote collection station side wall 552 define a cavity 556 . Cavity 556 preferably contains remote gas assembly 530 and remote sample assembly 540 . Cavity 556 is configured to physically isolate remote gas assembly 530 and remote sample assembly 540 from other components within cabinet 12 , such as low voltage contacts 204 and high voltage contacts 206 . This physical separation reduces the risk of death or injury to technicians from arcing while taking samples. To further increase safety, back wall 550 and remote collection station side wall 552 preferably comprise a conductive material, such as steel, and are conductively connected to side wall 602 . Preferably, cavity 556 is configured so that remote gas assembly 530 and remote sample assembly 540 are separated from low voltage contacts 204 and high voltage contacts 206 by a substantially continuous partition composed of one or more of back wall 550 , remote collection station side wall 552 , mounting flange 502 and side wall 602 .
FIGS. 6A and 6B show a side view of cabinet 12 . Cabinet 12 includes side wall 602 , which comprises remote collection station 50 . In FIG. 6A , the remote collection station 50 is shown in a closed configuration. In the closed configuration, the interior of the remote collection station 50 is inaccessible. Preferably, remote collection station 50 includes a lock 604 configured to restrict unauthorized access to the interior of remote collection station 50 and render its components tamper resistant. FIG. 6B shows a side view of cabinet 12 with remote collection station 50 in an open configuration, allowing access to remote gas assembly 530 and remote sample assembly 540 . Although remote gas assembly 530 and remote sample assembly 540 are accessibly, access to other components is blocked by back wall 550 and remote collection station side wall 552 .
FIG. 7 shows a rear view of remote collection station 50 . Mounting studs 506 are seen extending through side wall 602 . Mounting studs 506 are preferably 1″ long threaded rods which are welded to mounting flange 502 and are secured to side wall 602 by mounting nuts 714 . Portions of remote gas assembly 530 and remote sample assembly 540 are seen extending through back wall 550 . Remote gas assembly 530 and remote sample assembly 540 preferably include threaded portions and may be secured to a back wall 550 of the remote collection station 50 by ½″ nuts 712 . Remote gas assembly 530 and remote sample assembly 540 preferably comprise hose attachments 704 for connecting gas line 222 to remote gas assembly 530 and connecting oil sample line 224 to remote sample assembly 540 . Gas line 222 and oil sample line 224 are preferably secured to hose attachments 704 by hose clamps 706 .
In one embodiment, shown in FIG. 8 , the improvement disclosed herein may be offered as a kit comprising remote collection station 50 , remote gas assembly 530 , remote sample assembly 540 , gas line 222 , sample line 224 , T-junction 322 ( FIG. 3B ), first hose barb 324 ( FIG. 3B ), and second hose barb 424 ( FIG. 4B ). The kit may be used to improve safety for existing electrical equipment. The kit is preferably installed by first defining a hole (not shown) in side wall 602 using a knockout punch or a hole saw. Next, remote collection station 50 is temporarily placed in the hole, remote collection station 50 is leveled, and mounting holes locations are marked. Next mounting holes (not shown) are defined in side wall 602 , using a drill. Next, mounting studs 506 are positioned in the mounting holes and mounting nuts 714 are installed. Then, T-junction 322 and first hose barb 324 are added to gas port assembly 30 . Next, second hose barb 424 is attached to drain valve 40 . Next, gas line 222 and sample line 224 are cut to the desired length. Then, gas line 222 is connected to first hose barb 324 and sample line 224 is attached to second hose barb 424 . Next, gas line 222 and sample line 224 are secured to back wall 202 or side wall. After sample line 424 is attached, drain valve 40 should be opened.
Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the inventions, will be apparent to persons skilled in the art upon reference to the description of the invention. It is, therefore, contemplated that the appended claims will cover such modifications that fall within the scope of the invention. | An improved electrical equipment housing which includes an oil sample valve and a gas port assembly which are contained within the electrical equipment housing, yet are separated from electrical contacts and may be accessed without exposure to the electrical contacts. | 6 |
ASSIGNMENT
The entire right, title and interest in and to this application and all subject matter disclosed and/or claimed therein, including any and all divisions, continuations, reissues, etc., thereof are, effective as of the date of execution of this application, assigned, transferred, sold and set over by the applicant(s) named herein to Deere & Company, a Delaware corporation having offices at Moline, Ill. 61265, U.S.A., together with all rights to file, and to claim priorities in connection with, corresponding patent applications in any and all foreign countries in the name of Deere & Company or otherwise.
ASSIGNMENT
The entire right, title and interest in and to this application and all subject matter disclosed and/or claimed therein, including any and all divisions, continuations, reissues, etc., thereof are, effective as of the date of execution of this application, assigned, transferred, sold and set over by the applicant(s) named herein to Deere & Company, a Delaware corporation having offices at Moline, Ill. 61265, U.S.A., together with all rights to file, and to claim priorities in connection with, corresponding patent applications in any and all foreign countries in the name of Deere & Company or otherwise.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to vehicles, and more specifically to, a structure for swingably mounting a hood to a vehicle such as a lawn and garden tractor.
2. Description of Related Art
Access to the engine compartment of vehicles such as lawn and garden tractors is frequently necessary for making repairs, adjustments, and/or maintaining the engine and related components. Various mounting structures have been used to secure engine hoods, some permitting lifting or swinging separations of the hood from the engine compartment and others permitting a complete removal of the hood from the tractor. Such mounting structures, many of which employ pins, bolts, and similar structures, require the use of tools to enable the hood to be raised or removed from the tractor. After removal, these mounting structures usually require that the weight of the hood be supported by the operator as it is precisely positioned for reinstallation, thereby making installation difficult.
SUMMARY OF THE INVENTION
It would therefore be desirable to have a hood attachment structure that permits quick and easy access to the engine compartment as well as quick and easy removal of the hood when greater access is desired.
It would further be desirable to provide a hood attachment structure that is simple to remove or reinstall, requires no tools for removal or installation and one which could reliably secure the hood to the vehicle, whether raised or lowered. Further, it would be desirable to provide a hood mounting structure that permits the weight of the hood to be supported by the vehicle during the process of attaching it to or removing it from the vehicle.
Towards this end, there is provided a mounting structure composed of a pair of spaced apart pins carried by the tractor for engagement with spaced apart openings of a bracket mounted on the hood. A pair of guide surfaces on the bracket permit the hood to be supported on the vehicle frame while the pins are slidably positioned for alignment with openings in the bracket. A pair of fins are provided on one pin for alignment with keyway notches in one opening to prevent the pins from sliding out of the openings when the hood is swung into its mounted and closed position. Stops are also provided on the pins to signal when the pins are fully engaged as well as align the hood transversely on the vehicle.
With this structure, the hood is supported by the vehicle so it can be quickly and easily installed or removed without the use of tools. It can then be pivotally swung between the open and closed configurations and securely held in the open configuration since its center of mass is positioned forwardly of its pivoted connection with the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of the engine hood in its closed configuration in solid lines and in its raised configuration in phantom.
FIG. 2 is a side elevated perspective partial view illustrating the pivot mounting structure with the hood in its closed position.
FIG. 3 is a side elevated rear perspective partial view illustrating the pivot mounting structure of the frame and hood with the hood in its position for removal from or installation onto the vehicle.
FIG. 4 is a schematic side view of the mounting structure illustrating the position of the components when the hood is in its closed position.
FIG. 5 is a view similar to FIG. 4 illustrating the position of the mounting structure component when initially installing the hood onto the vehicle or when the hood is in its open position.
FIG. 6 is position similar to FIG. 4, illustrating the mounting components with the rod fins aligned with the keyways or notches for installation or removal of the hood onto the vehicle.
FIG. 7 is a side elevated perspective partial view illustrating an alternate mounting structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Looking first to FIG. 1, there is illustrated in schematic form a partial tractor vehicle 10 including a frame 12, right front wheel 14, and hood 16 shown in its closed position in solid lines. The hood 16 is illustrated in phantom in its forwardly tilted position. In this position, the center of gravity 18 of the hood 16 is located forwardly of the pivotal mounting structure 20 coupling the hood 16 with the tractor 10. The mounting structure 20 for pivotally securing the hood 16 with the tractor frame 12 includes a rod means 22 secured with the frame 12 and a bracket means 24 secured with the hood 16.
Looking now to FIGS. 2 and 3, there is illustrated in rear elevated perspective, a portion of the tractor frame 12 with the rod means 22 attached to it by rivets 26. Bolts, screws, welding or similar attaching structure could alternatively be used. Attached to the hood 16 is the bracket means 24 which forms the second basic part of the mounting structure 20. The bracket means 24 is preferably attached to the composite hood 16 of the preferred embodiment through the use of threaded bolts 28.
The rod means 22 includes first and second spaced apart end portions 30 and 32 with the second end portion 32 having latching means or fins 34 projected radially outwardly from the sides of a short length of the second rod end portion 32. Both end portions 30 and 32 of the rod means 22 are aligned with a transverse axis 36 to aid in alignment and positioning during installation.
The bracket means 24 is carried on the inside of the hood 16 at its forward lower portion (see FIG. 1 ). The bracket means 24 includes first and second spaced apart surfaces 38 and 40, formed as by bending of a flat material, into a generally C-shaped structure. The surfaces 38 and 40 have respective first and second openings 42 and 44 which are axially aligned to received the rod end portions 30 and 32. The second surface 40 is provided with radially extending notches or keyways 46 through which the fins 34 of the second rod end portion 32 can be received.
Further provided on the bracket means 24 are first and second guide surfaces 48 and 50 respectively positioned adjacent the bracket means surfaces 38 and 40. The first guide surface 48 extends transversely left of the first surface 38 (as viewed in FIGS. 2 and 3) to a greater extent than does the second guide surface 50 extend left of the second bracket surface 40. As is apparent from the side view of FIG. 5, the guide surfaces 48 and 50 project rearwardly away from the surfaces 38 and 40 of the bracket means 24 to essentially the same degree.
An alternative bracket means construction is illustrated in FIG. 7. This bracket means is comprised of two separate sub-brackets 124a, 124b and is intended to function the same as the bracket means 24 illustrated in FIGS. 1-6.
The sub-brackets 124a, 124b can be manufacted as separate stampings to reduce manufacturing costs or as a single bracket means if interconnected as illustrated with the dotted lines. The sub-brackets 124a, 124b include first and second spaced apart surfaces 138 and 140 with respective first and second openings 142 and 144 which are axially aligned to receive the rod portions 30 and 32. The second surface 140 is also provided with radially extending notches 146 through which the fins 34 of the second rod end portion 32 can be received. The sub-brackets further include first and second guide surfaces 148 and 150 which are positioned essentially the same as are the guide surfaces 48 and 50 of the FIG. 2-3 bracket means.
The sub-brackets 124a, 124b are each further provided with attaching ears 164 wherein openings 166 are formed to provide for additional attaching points to the hood 16. This type of additional attaching points can be provided as desired to better distribute the bracket loading to the hood 16. Also provided in the vehicle frame 12 are slotted attaching openings 168 which permit slight fore-and-aft adjustment of the rod means 22 on the vehicle.
Looking now to FIGS. 4, 5, and 6, there is illustrated the orientations of the rod means 22 and bracket means 24 when the hood 16 is respectively closed, open and then as it is when being installed or removed. These figures illustrate a side view of the second surface 40, the second rod means end portion 32, the second opening 44 and the second guide surface 50.
Looking first to FIGS. 3 and 6 to review the installation of the hood 16, it will be noted that the rod means 22 is carried on the top and forward portion of the vehicle frame 12. It projects forwardly in front of the vehicle to simplify installation of the hood 16. To install the hood 16, an operator first abuts the first leg 52 of the end portion 30 on the first guide surface 48. He would then slide the hood 16 sideways to the position illustrated in FIG. 3 so that the first tip 54 of the rod end portion 38 is closely aligned with the first opening 42 of the first surface 38. As the operator slides the bracket means 24 and hood 16 transversely to the left, as viewed in FIG. 3, the tip 54 of the first end portion 30 of the rod means 22 passes into the first opening 42. The length of the first end portion 30 is sized such that it can be partially inserted into the first opening 42 before the second end portion 32 begins to pass into the second opening 44. As the hood 16 is moved further to the left as viewed in FIG. 3, the second leg 56 of the end portion 32 would come into contact with the second guide means 50 to align the second end portion 32 With the second opening 44 of the second surface. During this process, the hood mounting components would be essentially as viewed in FIGS. 3 and 5.
As the legs 52 and 56 are further moved along the first and second guide surfaces 48 and 50 to insert end portions 30 and 32 into the openings 42 and 44, the hood 16 must be sightly rotated to align the fins 34 with the keyway or notches 46 in the second opening 44 (see FIG. 6). Each end portion 30 and 32 of the rod means 22 is provided with a stop 58 and 60 to limit the entry of the end portion 30 and 32 through its respective opening 42 and 44. The small lateral space 62 between the stop 60 and fins 34 effectively serves to transversely align the hood 16 with the vehicle frame 12, that alignment being restricted to the transverse space 62 between the fins 34 and the stop 60 of the second end portion 32 of the rod means 22.
To swing the hood 16 back and into place over the engine compartment, the operator next rotates the hood 16 about the axis 36 through the end portions 30 and 32 to swing the hood 16 into the orientation illustrated in solid lines in FIG. 1. In this hood-closed position, the mounting components will be as illustrated in FIG. 4. Since the fins 34 are now out of alignment with the keyways 46, as illustrated in FIG. 4, the hood 16 is locked or secured with the vehicle frame 12.
To open the hood 16, to the position illustrated in phantom in FIG. 1, and provide access to the engine compartment, the operator would simply lift the hood 16, pivoting the bracket means 24 about the axis 36 through the end portions 30 and 32 so that the mounting components are in the orientation as illustrated in FIG. 5. In this position, the guide surfaces 48 and 50 would abut the legs 52 and 56 of the end portions 30 and 32 to support the hood 16 in the position illustrated in phantom in FIG. 1 since the center of gravity 18 of the hood 16 is forwardly of the pivot axis 36.
When removal of the hood 16 is desired, the operator simply rotates the hood 16 to the position illustrated in FIG. 6 to align the notches 46 of the second opening 44 with the fins 34 of the second rod end portion 32 so that the hood 16 can be moved to the right, as viewed in FIG. 3, whereupon the end portions 30 and 32 can be removed from the openings 42 and 44. As the hood 16 is slid sideways, the weight of the hood 16 can be transferred through the guides 48 and 50 and to the rod means 22 to minimize the weight that the operator must support during the removal process.
With the present mounting structure, there is provided a means for quickly and easily mounting a hood onto a tractor frame where the weight of the hood can be supported in large part by the tractor frame during that operation. No tools are required as the end portions of the pins are aligned with the openings and the locking and latching features of the fins and notches provide a simple and easy method for securing the hood in place as it is swung between its open and closed position or supported in the completely open position. | A pivotable hood structure is provided for use with a vehicle such as a lawn and garden tractor. The structure includes a pair of spaced apart pins carried on the tractor frame near the front end to be receivable in bracket openings carried on the hood. The bracket includes guide surfaces which aid in positioning the pins relative to the openings while also supporting the weight of the hood during installation and removal of the hood. A latching structure is provided between the pins and bracket to secure the pins in place. The pivotable hood structure provides a swingable mounting for the hood as well as quick mounting or removal of the hood without requiring the use of tools. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional Patent Application 61/991,009 filed on May 9, 2014. That Provisional Patent Application is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates generally to the field of electrical terminal crimping machines and methodologies used in the crimp connection process. In particular, the invention relates to a device and method that facilitate effective, efficient, and reliable separation of a crimped wire terminal from a tape terminal carrier strip.
BACKGROUND
[0003] In the electrical connector industry, a crimp connection is commonly used to fuse a wire to a wire terminal. A “wire” can be a single wire or a cable comprised of more than one wire. A wire terminal that has not yet been fused to a wire is referred to as an “uncrimped wire terminal.” A wire terminal that has been fused to a wire is referred to as a “crimped wire terminal.”
[0004] Individuals desiring to create numerous crimp connections typically utilize an electrical terminal crimping machine in conjunction with a tape terminal carrier strip. A tape terminal carrier strip is a flexible tape that has numerous wire terminals attached to the tape terminal carrier strip and positioned side-by-side at evenly spaced intervals.
[0005] A conventional electrical terminal crimping machine has a power system and an applicator. The power system produces or conducts the power necessary for movement of the electrical terminal crimping machine's parts and can include electric, pneumatic, or hydraulic power systems.
[0006] The applicator has a feed mechanism, press assembly, and anvil, each connected to the applicator. The feed mechanism is attached to the applicator via standard fasteners and feeds the tape terminal carrier strip through the applicator. The press assembly is attached to the applicator via standard fasteners, is positioned vertically above the anvil, and has a press that is capable of engaging in vertical upward and downward motion. The anvil is attached to the applicator via a mounting hole and is located directly under the press assembly. The anvil has a crimp surface located on the top surface of the anvil.
[0007] As is known in the art, to create a crimp connection that fuses an uncrimped wire terminal to a wire, the feed mechanism advances the tape terminal carrier strip so that the uncrimped wire terminal, attached to the tape terminal carrier strip, is positioned directly below the press and rests on top of the crimp surface of the anvil. The terminal end of a wire is inserted into the receiving end of the uncrimped wire terminal. The press then moves in a downward vertical direction toward the anvil. The bottom surface of the press contacts the top surface of the uncrimped wire terminal, continues in the downward vertical direction, and applying downward force, momentarily sandwiches the uncrimped wire terminal between the bottom surface of the depressed press and the crimp surface of the anvil, creating a crimp connection that fuses the wire terminal to the wire. The press then moves vertically upward to return to its original position.
[0008] The feed mechanism then advances the tape terminal carrier strip laterally across the top surface of the anvil so that the newly crimped wire terminal, now fused to the wire, is no longer positioned directly below the press, thereby allowing the next successive uncrimped wire terminal attached to the tape terminal carrier strip to be positioned on the crimp surface of the anvil and located directly under the press.
[0009] After the crimp connection occurs, the crimped wire terminal, now fused to the wire, must be removed from the tape terminal carrier strip for industry use. In a conventional electrical terminal crimping machine, and with the conventional crimping method, after the fusion of the wire terminal to the wire and advancement of the tape terminal carrier strip, the newly crimped wire terminal remains in a position that is perpendicular to the tape terminal carrier strip and remains tightly attached to the tape terminal carrier strip.
[0010] Conventional electrical terminal crimping machine devices and crimp connection methods do not facilitate effective, efficient, or reliable removal of the crimped wire terminal from its attachment to the tape terminal carrier strip. Known adaptations for removal of a crimped wire terminal from the tape terminal carrier strip include use of a cutting tool to weaken or break the attachment between the crimped wire terminal and the tape terminal carrier strip, application of manual force to the wire to weaken or break the attachment between the crimped wire terminal and the tape terminal carrier strip, and adaptations to the feed mechanism. However, each one of these known adaptations suffers from one or more of the following disadvantages: non-productive downtime for the operator, damage to the crimped wire terminal or connected wire, damage to or jamming of the feed mechanism or tape terminal carrier strip.
[0011] Therefore, there is a need to adapt the electrical terminal crimping machine, as well as the conventional methods utilized to remove a crimped wire terminal from a tape terminal carrier strip, to facilitate effective, efficient, and reliable removal of a crimped wire terminal from the tape terminal carrier strip.
BRIEF SUMMARY
[0012] The preferred embodiments involve devices and methods for providing effective, efficient, and reliable removal of a crimped wire terminal from a tape terminal carrier strip. The devices and methods utilize an applicator for an electrical terminal crimping machine that has an anvil with a separation assistance device, in combination with advancement of the tape terminal carrier strip by the feed mechanism, to weaken the attachment between a crimped wire terminal and the tape terminal carrier strip in order to facilitate separation of a crimped wire terminal from the tape terminal carrier strip.
[0013] In one preferred embodiment, the separation assistance device has a ramp. In another preferred embodiment, the separation assistance device has a traveling ramp that is able to move in the vertical direction. In another preferred embodiment, the separation assistance device has a cylindrical pin.
[0014] A method is also provided for weakening the attachment between a crimped wire terminal and a tape terminal carrier strip to facilitate removal of the crimped wire terminal from the tape terminal carrier strip. The method generally includes: (1) providing a tape terminal carrier strip that has at least one uncrimped wire terminal attached to the tape terminal carrier strip, (2) feeding the tape terminal carrier strip through an electrical terminal crimping machine so that an uncrimped wire terminal rests on the top surface of an anvil and directly under a press, (3) inserting the terminal end of a wire into the receiving end of the uncrimped wire terminal positioned on the top surface of the anvil, (4) the downward vertical motion of the press, (5) the press applying downward vertical force to the top surface of the uncrimped wire terminal and momentarily sandwiching the uncrimped wire terminal and the inserted wire between the bottom surface of the depressed press and the top surface of the anvil, (6) the creation of a crimp connection that fuses the wire to the wire terminal, (7) the vertical upward movement of the press so that the press returns to its original position, (8) advancement of the tape terminal carrier strip so that the tape terminal carrier strip moves laterally across the top surface of the anvil, and (9) contact between a separation assistance device located on the anvil and the crimped wire terminal attached to the advancing tape terminal carrier strip so that the attachment between the crimped wire terminal and the tape terminal carrier strip is weakened.
[0015] In one preferred embodiment, the contact between the separation assistance device and the newly crimped wire terminal attached to the advancing tape terminal carrier strip causes the newly crimped wire terminal to move from a position in which the newly crimped wire terminal is perpendicular to the tape terminal carrier strip to a position in which the newly crimped wire terminal is positioned at non-perpendicular angle in relation to the tape terminal carrier strip.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] A complete understanding of the features, aspects, and advantages of the preferred embodiments will be obtained from the following description when taken in connection with the accompanying drawing figures, wherein like reference numerals identify the same parts throughout.
[0017] FIG. 1 is a front view of an electrical terminal crimping machine with an applicator that has one preferred embodiment, illustrating numerous uncrimped wire terminals all attached side-by-side to a tape terminal carrier strip, the leading uncrimped wire terminal resting on the top surface of the anvil in preparation for the crimp connection process.
[0018] FIG. 2 is a perspective front view of the applicator of FIG. 1 .
[0019] FIG. 3 is a perspective front view of the applicator of FIG. 2 and a perspective view of one preferred embodiment.
[0020] FIG. 4 is a perspective front view of one preferred embodiment.
[0021] FIG. 5 is a zoomed-in front view of the electrical terminal crimping machine of FIG. 1 .
[0022] FIG. 6 is a perspective side view of an electrical terminal crimping machine with an applicator that has one preferred embodiment, illustrating insertion of the terminal end of a wire into the receiving end of an uncrimped wire terminal in preparation for the crimp connection process.
[0023] FIG. 7 is a perspective side view of an electrical terminal crimping machine with an applicator that has one preferred embodiment, illustrating the creation of a crimp connection between a wire terminal and wire by the downward vertical motion of the press.
[0024] FIG. 8 is a perspective side view of an electrical terminal crimping machine with an applicator that has one preferred embodiment, illustrating advancement of the tape terminal carrier strip after the creation of a crimp connection and contact between one preferred embodiment and the newly crimped wire terminal.
[0025] FIG. 9A is a perspective front view of another preferred embodiment.
[0026] FIG. 9B is a perspective front view of yet another preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0000]
10 electrical terminal crimping machine
11 press assembly
12 applicator
13 press
14 tape terminal carrier strip
15 anvil
16 uncrimped wire terminal
17 feed mechanism
18 feed holes
22 key
24 mounting hole
28 separation assistance device
30 ramp
32 cylindrical pin
34 traveling ramp
36 wire
38 crimped wire terminal
40 crimp surface
[0045] Referring now to the drawings, FIG. 1 shows an electrical terminal crimping machine, generally designated 10 . The electrical terminal crimping machine 10 contains a power supply and an applicator 12 . As shown in FIGS. 1 and 8 , the applicator 12 has the various mechanical parts necessary to perform a crimp connection, including a feed mechanism 17 . A tape terminal carrier strip 14 having numerous evenly-spaced uncrimped wire terminals 16 , each attached to the tape terminal carrier strip 14 , is attached to the applicator 12 via the feed mechanism 17 .
[0046] The feed mechanism 17 feeds the tape terminal carrier strip 14 through the applicator 12 of the electrical terminal crimping machine 10 . In one preferred embodiment, the feed mechanism 17 feeds the tape terminal carrier strip 14 through the applicator 12 of the electrical terminal crimping machine 10 via feed holes 18 located on the tape terminal carrier strip 14 .
[0047] As shown in FIG. 2 , the applicator 12 has a press assembly 11 and an anvil 15 . The press assembly 11 is attached to the applicator 12 via at least one standard fastener. The press assembly 11 has a press 13 that is moveable in the vertical upward and downward directions as shown in FIG. 7 .
[0048] As shown in FIG. 3 , the anvil 15 is attached to the applicator 12 via a mounting hole 24 . As shown in FIG. 4 , the anvil 15 has a key 22 , a crimp surface 40 , and a separation assistance device 28 . The key 22 helps to ensure that the anvil 15 is properly attached to the applicator 12 and positioned directly under the press 13 . The crimp surface 40 of the anvil 15 could correspond to the type, size, and shape of uncrimped wire terminal 16 attached to the tape terminal carrier strip 14 .
[0049] In one preferred embodiment, the separation assistance device 28 has a ramp 30 . In one preferred embodiment, the ramp 30 has a rounded element. There are various possibilities for the orientation and angles of the top surface of the ramp 30 depending on the type, size, and shape of the uncrimped wire terminal 16 and wire 36 utilized in the crimp connection process.
[0050] As shown in FIG. 5 , during the crimp connection process, the tape terminal carrier strip 14 containing at least one uncrimped wire terminal 16 , and sometimes numerous attached uncrimped wire terminals 16 , is fed through the applicator 12 so that the leading uncrimped wire terminal 16 attached to the tape terminal carrier strip 14 rests on top of the crimp surface 40 of the anvil 15 in preparation for the crimp connection process. In one preferred embodiment, the press 13 also has a crimp surface 40 . The crimp surface 40 of the press could correspond to the type, size, and shape of uncrimped wire terminal 16 .
[0051] As shown in FIG. 6 , in general operation of an electrical terminal crimping machine 10 , an operator places the terminal end of a wire 36 into the receiving end of an uncrimped wire terminal 16 that is resting on top of the crimp surface 40 of the anvil 15 in preparation for the crimp connection process.
[0052] As shown in FIG. 7 , the press 13 moves vertically downward toward the anvil 15 , contacts the top surface of the uncrimped wire terminal 16 , and applying downward force, momentarily sandwiches the uncrimped wire terminal 16 between the bottom surface of the depressed press 13 and the crimp surface 40 of the anvil 15 , thereby creating a crimp connection and fusing the uncrimped wire terminal 16 to the wire 36 .
[0053] As shown in FIG. 8 , the press 13 then moves vertically upward to its original starting position while the feed mechanism 17 advances the tape terminal carrier strip 14 through the applicator 12 of the electrical terminal crimping machine 10 , and moves the newly crimped wire terminal 38 laterally away from the crimp surface 40 of the anvil 15 and across the top surface of the anvil 15 , thereby positioning the next successive uncrimped wire terminal 16 attached to the tape terminal carrier strip 14 directly on top of the crimp surface 40 of the anvil 15 in preparation for the crimp connection process. During this lateral advancement motion initiated by the feed mechanism 17 , the separation assistance device 28 contacts the crimped wire terminal 38 that is still attached to the tape terminal carrier strip 14 , and applies angular force to the newly crimped wire terminal 38 . This angular force applied by the separation assistance device 28 weakens the crimped wire terminal's 38 attachment to the tape terminal carrier strip 14 .
[0054] As shown in FIG. 8 , in one preferred embodiment, at the end stage of the lateral advancement movement initiated by the feed mechanism 17 , the newly crimped wire terminal 38 rests on top of the separation assistance device 28 so that the newly crimped wire terminal 38 is positioned at a non-perpendicular angle in relation to the tape terminal carrier strip 14 and prepared for separation from the tape terminal carrier strip 14 . The newly crimped wire terminal 38 that has a weakened attachment to the tape terminal carrier strip 14 is then separated from the tape terminal carrier strip 14 either by manual force or other separating means.
[0055] As shown in FIG. 9A , another preferred embodiment has an anvil 15 with a separation assistance device 28 that has a traveling ramp 34 . The traveling ramp 34 is able to move in the vertical direction, and is able to be under various tensions. The traveling ramp 34 applies an upward angular force to the crimped wire terminal 38 as the crimped wire terminal 38 moves laterally across the top surface of the anvil 15 so that the crimped wire terminal's 38 attachment to the tape terminal carrier strip 14 is weakened in preparation for removal of the crimped wire terminal 38 from the tape terminal carrier strip 14 . In one preferred embodiment, the top surface of the traveling ramp 34 has a rounded element as shown in FIG. 9A . There are various possibilities for the orientation and angles of the top surface of the traveling ramp 34 depending on the type, shape, and size of the uncrimped wire terminal 16 and wire 36 utilized in the crimp connection process. In one preferred embodiment, the traveling ramp 34 is limited by a mechanical stop (not shown) so that the separation assistance device 28 is prevented from interfering with the crimped wire terminal 38 and attached wire 36 .
[0056] As shown in FIG. 9B , another preferred embodiment has an anvil 15 with a separation assistance device 28 that has a cylindrical pin 32 . The cylindrical pin 32 could be positioned laterally to the crimp surface 40 of the anvil 15 and below the top surface of the crimp surface 40 of the anvil 15 so that the cylindrical pin 32 applies a force to the crimped wire terminal 38 as the crimped wire terminal 38 moves laterally across the top surface of the separation assistance device 28 and thereby weakens the attachment of the crimped wire terminal 38 to the tape terminal carrier strip 14 . There are various possibilities for the orientation of the cylindrical pin 32 depending on the type, shape, and size of the uncrimped wire terminal 16 and wire 36 utilized in the crimp connection process.
[0057] The present examples and embodiments are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein. | Devices and methods to facilitate separation of a crimped wire terminal from a tape terminal carrier strip. The devices and methods weaken the attachment between the crimped wire terminal and the tape terminal carrier strip to facilitate effective, efficient, and reliable removal of the crimped wire terminal from the tape terminal carrier strip. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 10/135,315, filed Apr. 29, 2002, now abandoned, which claims the benefit of U.S. Provisional Patent Application No. 60/301,200 filed Jun. 27, 2001.
FIELD OF THE INVENTION
The present invention relates to a plastic blow molded bottle or wide mouth jar useful in containing hot-filled beverages or food products, and more particulary, the present invention relates to a container having a multi-sided sidewall which is reinforced to resist unwanted deformation, which enables a label to be aesthetically displayed on the container sidewall, and which is capable of accommodating vacuum associated with hot filling, capping and cooling of the container.
BACKGROUND OF THE INVENTION
Hot-fillable, blow-molded plastic containers are well known in the art. The problems associated with accommodating vacuum deformations associated with hot filling, capping and cooling, and their solutions are also well known. Typically, so-called vacuum flex panels are formed as relatively large indented panels in the sidewall of containers and accommodate the vacuum that develops in the containers as a result of hot fill processing. Examples of cylindrical containers having indented flex panels are disclosed in U.S. Pat. No. 5,762,221 issued to Tobias et al.; U.S. Pat. No. D.402,563 issued to Prevot et el.; U.S. Pat. No. D.366,831 issued to Semersky et al.; and U.S. Pat. No. D.366,416 issued to Semersky.
Hot-fillable blow-molded containers having multi-sided sidewall configurations with indented vacuum flex panels are disclosed, for example, by U.S. Pat. No. 5,178,290 issued to Ota et al. and U.S. Pat. No. 5,238,129 issued to Ota. In particular, FIGS. 7-8 of the Ota '290 patent and FIGS. 5-8 of the Ota '129 patent illustrate and disclose hexagonal and octagonal container sidewall configurations which have indented flex panels.
Hot-fillable, multi-sided containers have also been provided with a series of walls which are formed planar and which bow, flex, or warp inwardly in response to induced vacuum. Thus, the resulting shape of each panel of such hot-filled, capped and cooled containers is concave, or inwardly bowed, thereby providing the sidewall with an undulating shape in plan. Examples of such containers are disclosed by U.S. Pat. No. 4,749,092 issued to Sugiura et al. and U.S. Pat. No. 4,497,855 issued to Agrawal et al. For instance, see FIGS. 2 and 5 of the '092 Sugiura patent and FIG. 7 of the Agrawal '855 patent. U.S. Pat. No. 3,923,178 issued to Welker, III discloses another multi-sided container having a plurality of sidewall panels which, as-formed, are planar and which are designed to flex inwardly. For instance, see FIG. 7 of the Welker, III '178 patent.
Other related container designs are disclosed by U.S. Pat. No. 4,946,053 issued to Conrad which discloses an ovalized label panel for a hot-fillable bottle having a circular footprint; U.S. Pat. No. 5,908,127 issued to Weick et al. which discloses an ovalized or “rounded-off” rectangular sidewall of a hot-fillable bottle having front and rear outwardly bowed panels; and U.S. Pat. No. 5,690,244 issued to Darr which discloses a paneled sidewall of a jar having a circular footprint. Also see the container configurations disclosed in U.S. Pat. No. 4,818,575 issued to Hirata et al.; U.S. Pat. No. 5,866,419 issued to Meder; U.S. Pat. No. D.189,372 issued to Adell; U.S. Pat. No. D.402,896 issued to Conrad; U.S. Pat. No. D.318,422 issued to Rumney; U.S. Pat. No. D.418,760 issued to Blank; and U.S. Pat. No. D.419,886 issued to Gans.
A problem experienced with hot-fillable containers having flex panels, particularly indented or concave flex panels, is that voids are created within the label mounting region behind the labels. Voids behind a label can prevent the label from being prominently displayed on the container sidewall and can provide areas on the label which are prone to tearing, undesirable stretching, or the like. In addition, the use of certain labels, such as shrink wrap labels, can result in the labels extending into, or shrinking within, the voids which also negatively effects container aesthetics.
Another problem experienced with hot-fillable containers is the occurrence of creases, dents or like deformations in the sidewalls of the containers which damage, weaken, and/or detract from the aesthetics of the container. Such deformations can result, for instance, due to line pressure experienced during transferring, filling, capping and packing operations. To this end, adjacent containers in such operations can become tightly engaged, particularly adjacent the base and lower bumper areas of the containers, thereby causing at least selected ones of the containers from being dented or provided with undesirable crease marks. More specifically, multi-sided containers typically experience such deformations adjacent the vertical post structures adjacent the base of the containers.
A still further problem relates to the occurrence of creases, dents or like deformations in the sidewalls of the containers experienced as a result of shipping and handling of the containers due to inadequate top loading or drop capability. To this end, creases or dents can result in containers located in bottom rows of containers on which many other rows of containers are stacked during shipping. In addition, forces exerted on the containers during loading and unloading of the stacked containers can also cause creases and dents. Multi-sided containers are particularly prone to such deformation along post structures adjacent the base of the containers along an area of contact of the containers with adjacent containers in the stack.
Although various ones of the above referenced containers may function satisfactorily for their intended purposes, there is a need for a hot-fillable, blow-molded container having a flex panel and sidewall structure which permits a label to be completely wrapped around the container sidewall and prominently displayed thereon and which limits voids behind the label. In addition, preferably the sidewall structure should be multi-sided and should be reinforced to resist creasing, denting and the occurrence of like deformations. Further, the container should provide improved top loading capability and improved drop testing results. Still further, the container should be capable of efficient and relatively inexpensive manufacture and should be capable of being made from a minimum of thermoplastic material.
OBJECTS OF THE INVENTION
With the foregoing in mind, a primary object of the present invention is to provide a blow-molded plastic bottle and/or wide mouth jar having a multi-sided sidewall capable of accommodating induced vacuum within a hot-filled, capped and cooled container.
Another object of the present invention is to provide a hot-fillable, multi-sided container providing a label mounting area which encompasses flex panel structures on the sidewall and which can prominently support and display a label, including shrink wrap labels and the like.
A further object is to provide a hot-fillable, multi-sided, plastic, blow-molded container which provides a novel visual appearance and which has enhanced structural integrity.
SUMMARY OF THE INVENTION
More specifically, the present invention provides a hot-fillable plastic container provided by a blow molded plastic container body having a circular base, a sidewall, a circular lower bumper between the base and sidewall, and a dome having an upstanding finish. The sidewall has a plurality of panels positioned circumferentially in a side-by-side relationship about the sidewall thereby forming a multi-sided sidewall structure. Each adjacent pair of panels interconnect at an obtuse angle and form a vertically-extending post structure which extends continuously through the multi-sided sidewall structure.
Each panel, as-formed, has a section which is arcuate in a plane extending perpendicular to an imaginary central axis extending longitudinally through the container. The arcuate sections provide the panel with a slightly outward bow and are formed having a predetermined radius of curvature within a predetermined range of radius of curvatures. Preferably, the radius of curvature of the panels varies along the length of the panels. This structure permits the arcuate sections of the panels to flex inwardly for accommodating induced vacuum created when the container is hot-filled, capped and cooled.
Each panel also has an inset circumferentially-extending reinforcement area adjacent the lower bumper of the container. Each inset area extends between an adjacent pair of the post structures and terminates a spaced distance from the post structures to reinforce and strengthen the circular lower bumper and post structures. This structure enables the container to resist creasing, denting and like deformation, and enhances top loading capability and drop testing results.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the present invention should become apparent from the following description when taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view of a container embodying the present invention with the dome of the container being illustrated in phantom;
FIG. 2 is a cross-sectional view of the container illustrated in FIG. 1 taken longitudinally of the container along line 2 — 2 ;
FIG. 3 is a cross-sectional view of the container taken transversely through the container along line 3 — 3 of FIG. 2 ;
FIG. 3 is a cross-sectional view of the container taken transversely through the container along line 3 — 3 of FIG. 2 ;
FIG. 4 is a cross-sectional view of the container taken transversely through the container along line 4 — 4 of FIG. 2 ;
FIG. 5 is a cross-sectional view of the container taken transversely through the container along line 5 — 5 of FIG. 2 ;
FIG. 6 is a cross-sectional view of the container taken transversely through the container along line 6 — 6 of FIG. 2 ; and
FIG. 7 is a cross-sectional view of the container taken transversely through the container along line 7 — 7 of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of a blow-molded plastic container body 10 according to the present invention is illustrated in FIG. 1 . The illustrated container body 10 is utilized to package beverages, such as juice, and is capable of being filled in either high-speed hot-fill or cold fill operations. The container 10 can be manufactured in various sizes to provide a fill capacity of, for instance, 64 fluid ounces. Of course, the container 10 can be made smaller, or larger, to provide any desired pre-determined capacity and also can be made having a wide-mouth finish so that the container can be utilized as a jar to package food products, such as, sauces, relishes, pickles, and the like.
As best illustrated in dashed lines in FIGS. 1 and 2 , the container body 10 has a dome 12 with an upstanding finish 14 . The particular shape of the dome can vary as desired. In the illustrated embodiment, the dome 12 has a lower end 12 a providing an upper label bumper 16 which is circular and which projects outwardly directly above an inset circumferential groove 18 . The groove 18 provides hoop strength and resists ovalization-type distortion of the container body 10 . Preferably, the finish 14 is provided in narrow sizes for beverage bottle-type containers and is provided in wide-mouth sizes for jar-type food containers. In addition, the finish 14 can be an injection molded finish or a blown finish and is preferably provided with threads for cooperatively engaging a cap (not shown) used to seal the container body 10 .
Preferably, a closed ended base 20 provides the container body 12 with a circular footprint. An outer peripheral sidewall 20 a of the base 20 provides a lower label bumper 22 which, as illustrated, is circular. An endwall 24 of the base 20 can be of any desired shape, such as, a concave-shaped base structure 26 as shown in FIG. 2 . To this end, the base 20 is a so-called push-up style base and is capable of accommodating a percentage of the induced vacuum created in a hot-filled, capped and cooled container.
One important aspect according to the present invention is that the container body 10 has a multi-sided sidewall 28 which extends between the dome 12 and base 20 . In the illustrated embodiment, the entire sidewall 28 is multi-sided and provides a label mounting region 30 extending between the upper and lower label bumpers, 16 and 22 . Alternatively, although not illustrated, only a portion of the sidewall 28 need be formed as a multi-sided structure, and the label mounting region can be limited to less than the entire sidewall 28 .
In the preferred embodiment, a label (not shown) can be applied to the sidewall 28 to cover the entire sidewall 28 and extend 360° about the sidewall 28 . For example, the label can be a paper label adhesively applied to the sidewall 28 or a tubular plastic shrink wrap label shrunk to tightly engage the sidewall 28 . Most importantly, the container body 10 is capable of prominently displaying these and other types of labels because the sidewall 28 has relatively few voids, or sunken areas, behind the label.
As illustrated, the multi-sided sidewall 28 is formed by six panels 32 positioned in a side-by-side relationship about the periphery of the sidewall 28 . Each pair of adjacent panels 32 interconnect at an obtuse angle “A”, and a column, or post, 34 is formed at each interconnection. Thus, the illustrated container body 10 has six circumferentially-spaced, longitudinally-extending posts 34 . Preferably, each panel 32 is identical in shape and size, and only a corner-shaped post 34 is located between each pair of adjacent panels 32 . Alternatively, at least selected ones of the panels can be provided with a different shape and/or dimension, and intermediate structures can be located between each adjacent pair of panels. In addition, the number of panels 32 utilized to form the sidewall can vary, such as within a range of 3 to 12 panels.
Preferably, each panel 32 has at least a section 36 thereof which is flexible to accommodate induced vacuum created in a hot-filled, capped and cooled container. In accordance with the objectives of the present invention to reduce the number of voids or the like behind a label and to enhance the prominence of the display provided by the label, the flexible sections 36 are not formed as indented structures. Rather, the flexible sections 36 of the panels 32 are formed with a slight gentle outward bow between each pair of adjacent posts 32 . For example, as illustrated in FIG. 6 , the section 36 is arcuate in a plane “P 1 ” extending perpendicular to an imaginary central axis “C L ” of the container body 10 and is formed at a predetermined radius of curvature “Rc 1 ”. Also see the cross-sections of the panels 32 which are illustrated in FIGS. 3 , 4 , and 5 along planes “P 4 ”, “P 3 ” and “P 2 ”, respectively, and which are formed at predetermined radius of curvatures “Rc 4 ”, “Rc 3 ” and “Rc 2 ”, respectively.
When the container body 10 is hot-filled and capped and as the hot-filled container body 10 and its contents cool, a vacuum is created which reduces the internal volume of the sealed container. The outwardly bowed sections 36 of the panels 32 of the container body 10 accommodate the vacuum by flexing inwardly to a substantially flattened condition. Thus, the sidewall 28 of the hot-filled, capped and cooled container body 10 maintains a uniform multi-sided configuration and is capable of prominently displaying a label.
According to one contemplated embodiment of the present invention, the outward bow of the flexible sections 36 of the panels 32 , as-formed, becomes either greater, or gentler, as the panel extends in a direction parallel with the central axis “C L ”. For example, section 36 of each panel 32 bows outward to a greatest extent in plane “P 1 ” and flattens as the panel 32 extends upwardly toward plane “P 4 ”. To this end, sections 36 a illustrated in FIG. 5 are flatter and have a greater radius of curvature than sections 36 b illustrated in FIG. 6 . Preferably, the radius of curvature “Rc 1 ” defines a minimum radius of curvature of the section 36 of the panel 32 , and the radius of curvature “Rc 2 ” defines a maximum radius of curvature. In addition, preferably the minimum and maximum radius of curvatures are within 5% of one another so that the change in radius of curvature, if any, is gentle and difficult to visualize.
As an alternative to the above discussed and illustrated structure of the flexible sections 36 of the panels 32 , the entire flexible section 36 , or each entire panel 32 , can be formed having a constant radius of curvature. Another alternative is for the sections 36 to flatten as the sections 36 extend in a direction toward the base 20 . Yet another alternative is a flexible section 36 which is provided with upper and lower arcuate areas and a relatively flat intermediate area located therebetween (ie. a so-called “H-panel” structure).
An advantage of providing a multi-sided sidewall 28 having panels 32 which flex inwardly according to the present invention is that as the panels accommodate vacuum they are also reinforcing the post strength of the sidewall 28 by pinching, and preferably vertically-straightening, the posts 34 formed at the interconnection of each adjacent pair of panels 32 . For instance, the obtuse angle “A” of the interconnection between adjacent panels 32 , as formed, reduces as the outwardly bowed flexible sections 36 flatten. Thus, the posts 34 progressively become stiffer as the sidewall 28 accommodates the induced vacuum and provides the filled and sealed container body 10 with improved top-loading capability.
Preferably, the posts 34 on the multi-sided sidewall 28 are continuous and without interruption thereby maximizing top-loading capability of the container body 10 . In addition, preferably at least a portion of each post 34 is located adjacent an inset reinforcement area, or rib, 38 . The ribs 38 are located on each panel 32 adjacent areas of the posts 34 that tend to crease or dent due to line pressures which are experienced during transferring, filling, capping, and packing operations and which result in adjacent containers being forced tightly together in a restricted amount of space.
Preferably, one circumferentially-extending rib 38 is located on each panel 32 between and adjacent the lower label bumper 22 and the flexible sections 36 of the panels 32 . As best illustrated in FIG. 7 , each rib 38 extends between an adjacent pair of posts 34 and does not interrupt the posts 34 to permit the posts 34 to extend continuously from the groove 18 of the dome 12 to the lower label bumper 22 of the base 20 . The ribs 38 function to reinforce and strengthen the lower label bumper 22 and the posts 34 and to prevent deformation thereof. In addition, the ribs 38 permit the arcuate flexible sections 36 to flatten, yet reinforce the sections 36 from unwanted inward denting and like deformation. Thus, creasing and like deformations which structurally weaken and blemish the aesthetics of the container body 10 are prevented at locations particulary susceptible to such deformations.
By way of example and not by way of limitation, the container body 10 is manufactured of PET utilizing injection blow-molding techniques. Of course, other plastic materials and multi-layered plastic materials can be utilized as well as other blow molding techniques. The container body 10 is dimensioned to have a capacity of 64 fluid ounces and a multi-sided sidewall with a total of six identical panels 32 . Each panel 32 has a flexible section 36 which, as formed, bows outwardly. A lower portion of the flexible section 36 has a radius of curvature of about 5.5 inches and an upper portion of the flexible section has a radius of curvature of about 5.7 inches. The sidewall 28 has six vertically extending posts 34 , and each panel 32 has one circumferentially extending inset rib 38 which is located between and adjacent the lower label bumper 22 and the flexible sections 36 . Each rib 38 terminates a spaced distance from an adjacent pair of posts 34 , and preferably the innermost walls 40 of the ribs 38 are planar as illustrated in FIG. 7 and have ends 42 which interconnect to form a portion of the posts 34 . In addition, preferably the upper and lower label bumpers 16 and 22 are circular in plan and the base 20 of the container body 10 provides a circular footprint. Finally, each panel 32 has three longitudinally-spaced, circumferentially extending inset reinforcement ribs 44 which prevent unwanted over flexure of the panels 32 and assures that the panels 32 uniformly accommodates the induced vacuum.
While a preferred hot-fillable container body having a multi-sided sidewall has been described in detail, various modifications, alterations and changes may be made without departing from the spirit and scope of the present invention as defined in the appended claims. | A plastic blow molded bottle or wide mouth jar useful in containing hot-filled beverages or food products. The container has a multi-sided sidewall which is capable of accommodating vacuum associated with hot filling, capping and cooling of the container, which is reinforced to resist unwanted deformation, and which enables a label to be aesthetically displayed on the container sidewall. To this end, the sidewall comprises a plurality of panels which include outwardly bowed arcuate sections, as-formed, which flatten to accommodate induced vacuum. Thus, a label can be supported on the sidewall with very few voids, or like sunken areas, behind the label to ensure that the label is prominently displayed on the aesthetically appealing novel container configuration. | 1 |
This application claims priority from Japanese Patent Application No. 2008-310931, filed on Dec. 5, 2008, the entire contents of which are incorporated by reference herein.
TECHNICAL FIELD
The present disclosure relates to a field device performing a communication through a communication line.
RELATED ART
Normally, a hardware design of the field device is based on its output mode. For example, a hardware configuration is widely different between the two-wire type field device whose output is in proportion to a current consumption and the bi-directional digital communication equipment typified by FOUNDATION Fieldbus (FF; trademark) or Profibus PA (see e.g., US2005/0232305 A1).
Like FOUNDATION Fieldbus (FF; trademark) and Profibus PA, when the specification of the physical layer is identical and a transmission speed is equal, the approach of selecting a communication system by checking the frame contents upon starting the power supply has been proposed. However, from the vender's viewpoint of the field device, there are problems such as:
(1) various different types of hardwares must be developed;
(2) a developing efficient is lowered because the management of the developed software are needed;
(3) the stock control in a manufacturing factory are needed; and
(4) the management of stock and spare parts in the factory becomes troublesome from the user's viewpoint.
Also, when the fieldbus device is mistakenly connected instead of the two-wire type field device in exchanging the device, the system may be badly affected. For example, since a current consumption of the fieldbus device is always about 10 mA to 15 mA, it is possible that the signal is misread as the 4-20 mA signal and the influences on the system are feared.
That is, in the fieldbus device, the transmission speed thereof is high (about 31.25 Kbps) and is largely different from the transmission speed (about 1200 bps) that is superposed on the signal line in the 4-20 mA type two-wire transmitter. As a result, a current consumption of about 10 mA or more is required in the fieldbus device. In contrast, the conventional 4-20 mA type two-wire transmitter such as HART must be operated under the current consumption of about 4 mA or less. Therefore, basic designs of both devices are different from each other in light of the current consumption.
SUMMARY OF THE INVENTION
Exemplary embodiments of the present invention address the above disadvantages and other disadvantages not described above. However, the present invention is not required to overcome the disadvantages described above, and thus, an exemplary embodiment of the present invention may not overcome any of the problems described above.
Accordingly, it is an illustrative aspect of the present invention to provide a field device capable of responding to various output modes easily and safely.
According to one or more illustrative aspects of the present invention, there is provided a field device performing a communication through a communication line. The field device includes: first circuits involved with a smart communication; second circuits involved with a fieldbus communication; a token detecting circuit that detects a token in the fieldbus communication; and a control circuit. The control circuit is operable to: i) cause the second circuits to operate when the token is detected within a given time by the token detecting circuit; and ii) cause the second circuits not to operate when the token is not detected within the given time by the token detecting circuit.
According to the present invention, the communication mode is switched depending on whether or not the token is detected within a given time. As a result, the field device can respond to plural output modes easily and safely.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a block diagram showing a configuration of a field device according to an exemplary embodiment of the present invention:
FIG. 1B is a block diagram showing a control system for switching a function of the field device shown in FIG. 1A .
FIG. 2 is a flowchart showing steps of selecting the function of the field device according to the exemplary embodiment.
FIG. 3A is a block diagram showing the field device acting as a fieldbus device.
FIG. 3B is a block diagram showing the filed device acting as a two-wire type field device.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Exemplary embodiments of the present invention will be now described with reference to FIG. 1 to FIG. 3B .
FIG. 1A is a block diagram showing a configuration of a field device 1 according to an exemplary embodiment of the present invention, and FIG. 1B is a block diagram showing a control system for switching a function of the field device 1 .
As shown in FIG. 1A , the field device 1 includes: a sensor circuit 11 for providing a sensor function of the field device 1 , and a CPU 12 for executing the overall control of the field device 1 . The field device 1 further includes: a RAM 13 ; a ROM 14 ; and; a gate array 15 in which logical circuits such as an address decorder, an external watchdog timer are built. Also, the RAM 13 , the ROM 14 and the gate array 15 are connected to the CPU 12 , respectively.
Also, as the elements for the two-wire type transmission system, the field device 1 further includes: a BRAIN/HART receive circuit 21 ; a BRAIN/HART transmit circuit 22 ; and a 4-20 mA output circuit 23 , which can cope with the lower-speed smart communication (e.g., BRAIN communication, HART (registered trademark) communication).
Meanwhile, as the elements for the fieldbus transmission system, the field device 1 further includes: a fieldbus communication receiving circuit 31 ; a fieldbus communication transmitting circuit 32 ; and a fieldbus modem 33 , which can cope with the high-speed fieldbus communication.
The field device 1 further includes: an output stage switch circuit 41 for switching a connection state with respect to a bus 5 ; and a baud rate detect circuit 42 for detecting presence/absence of the communication signal on the bus 5 and a transmission speed. The field device 1 further includes: a power supply circuit 43 for supplying an electric power to respective circuits (elements) of the field device 1 ; and a clock supply circuit 44 for supplying a clock signal to respective circuits (elements) of the field device 1 (see FIG. 1B ). A clock frequency of the clock supply circuit 44 can be switched in response to the transmission speed.
As shown in FIG. 1B , the output stage switch circuit 41 , the baud rate detect circuit 42 , the power supply circuit 43 , and the clock supply circuit 44 are connected to the CPU 12 , respectively. The function of the field device 1 is selected by controlling the output stage switch circuit 41 , the power supply circuit 43 , and the clock supply circuit 44 in response to the result detected by the baud rate detect circuit 42 .
Then, respective steps of selecting the function of the field device 1 will be now described.
FIG. 2 is a flowchart showing steps of selecting the function of the field device 1 . The respective steps are executed when the field device 1 is started under control of the CPU 12 .
At Step S 1 of FIG. 2 , as the initial setting, a supply clock supplied from the clock supply circuit 44 is set to a frequency corresponding to the smart communication whose transmission speed is low. This is because an overall power consumption is increased when the supply clock is set to a high frequency corresponding to the fieldbus communication. As a result, there is possibility that the 4-20 mA signal acting as the main output signal is badly influenced when the signal superposed on the power supply line is the smart communication.
Also, at Step S 1 , the CPU, the BRAIN/HART receive circuit 21 , the BRAIN/HART transmit circuit 22 , the 4-20 mA output circuit 23 , the fieldbus communication receiving circuit 31 , and the baud rate detect circuit 42 are selected as the destination of the electric power supplied from the power supply circuit 43 . In order to suppress the current consumption, the electric power is not supplied the fieldbus communication transmitting circuit 32 and the fieldbus modem 33 .
Then, at Step S 2 , it is detected whether or not the frame is present on the bus 5 by the baud rate detect circuit 42 .
Then, at Step S 3 , a monitor timer for deciding a frame monitoring time (given time) is started. The frame monitoring time is set in light of the characteristics of the fieldbus communication and the smart communication. That is, since the bi-directional digital communication is employed in the fieldbus communication, the host device always transmits a token (e.g., probe node (PN) in the case of the FF device) onto the bus 5 as the frame so as to check the presence of the target device. By way of example, an interval in which the token is transmitted is set in order of several msec in the FF device. Also, even when the host device becomes silent due to any trouble, normally an interval is set within about 10 msec until the backup host device starts to transmit the frame such as Claim LAS. Accordingly, it can be decided that when the silent state is continued for e.g., 1 sec, the fieldbus communication is not held. Thus, the frame monitoring time of about 1 sec is an enough time.
Then, at Step S 4 , it is decided whether or not time of the monitoring timer runs out. The process goes to Step S 5 immediately after time-out of the monitoring timer.
At step S 5 , it is decided whether or not the frame is detected within the monitoring time. The process goes to Step S 6 if the frame is detected (YES), whereas the process goes to Step S 10 if the frame is not detected (NO).
At Step S 6 , it is decided whether or not the frame detected by the baud rate detect circuit 42 corresponds to the smart communication. If the detected frame corresponds to the frame (token) of the smart communication, the process goes to Step 10 . In contrast, if the frame detected by the baud rate detect circuit 42 corresponds to the frame (token) of the fieldbus communication, the process goes to Step 7 .
At Step S 7 , the supply clock supplied from the clock supply circuit 44 is switched to a frequency corresponding to the fieldbus communication whose transmission speed is high.
Then, at Step S 8 , under control of the power supply circuit 43 , a power supply to the circuits (elements) involved with the smart communication is stopped and a power is supplied to the circuits (elements) involved with the fieldbus communication, i.e., the baud rate detect circuit 42 , the fieldbus communication receiving circuit 31 , the fieldbus communication transmitting circuit 32 , and the fieldbus modem 33 . Then, at Step S 9 , the connection state with respect to the bus 5 is switched to the fieldbus communication under control of the output stage switch circuit 41 .
FIG. 3A is a block diagram showing an operation state of the field device 1 after the process of Step S 8 is ended. Here, only the circuits (elements) involved with this operation state are extracted. In this manner, the field device 1 acts as the fieldbus device, and the process goes to the steady-state as the field device at Step S 12 and the process for start-up of the field device 1 is ended.
In contrast, at step S 10 , under control of the power supply circuit 43 , a power supply to the circuits (elements) involved with the fieldbus communication is stopped and a power is supplied to the circuits (elements) involved with the smart communication, i.e., the baud rate detect circuit 42 , the BRAIN/HART receive circuit 21 , the BRAIN/HART transmit circuit 22 , and the 4-20 mA output circuit (first communicating means) 23 . Then, at Step S 11 , the connection state with respect to the bus 5 is switched to the smart communication under control of the output stage switch circuit 41 .
FIG. 3B is a block diagram showing an operation state of the field device 1 after the process of Step S 11 is ended. Here, only the circuits (elements) involved with this operation state are extracted. In this manner, the field device 1 acts as the two-wire type field device, and the process goes to the steady-state as the two-wire type field device at Step S 12 and the process for start-up of the field device 1 is ended.
As described above, the field device 1 of the exemplary embodiment can determine automatically either the fieldbus communication or the smart communication based on presence/absence of the frame on the bus 5 and the detected result of the baud rate. Also, the field device 1 can act as either of the fieldbus device or the two-wire field device. Therefore, not only the individual development required for the type of the field device is not needed, but also the troublesome operations such as the stock control are not needed.
Also, the power supply is applied only to the circuits (elements) required for the detection when the baud rate is detected. Also, the power supply is applied only to the necessary circuits (elements) depending on whether the field device 1 acts as the fieldbus device or the two-wire field device after the baud rate is detected. Accordingly, the overall power consumption can be suppressed, and the harmful influence on the system can be avoided.
In the exemplary embodiment, the FF bus is illustrated as the fieldbus. However, the exemplary embodiment is not limited thereto. For example, the present invention is also applicable to another fieldbus such as Profibus PA.
While the present invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It is aimed, therefore, to cover in the appended claim all such changes and modifications as fall within the true spirit and scope of the present invention. | There is provided a field device performing a communication through a communication line. The field device includes: first circuits involved with a smart communication; second circuits involved with a fieldbus communication; a token detecting circuit that detects a token in the fieldbus communication; and a control circuit. The control circuit is operable to: i) cause the second circuits to operate when the token is detected within a given time by the token detecting circuit; and ii) cause the second circuits not to operate when the token is not detected within the given time by the token detecting circuit. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 11/111,481 filed 21 Apr. 2005, which claims priority under 35 U.S.C. 119 to UK Application No. GB0408876.1, filed 21 Apr. 2004, the disclosures of which are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
This invention relates to a network interface, for example an interface device for linking a computer to a network.
FIG. 1 is a schematic diagram showing a network interface device such as a network interface card (NIC) and the general architecture of the system in which it may be used. The network interface device 10 is connected via a data link 5 to a processing device such as computer 1 , and via a data link 14 to a data network 20 . Further network interface devices such as processing device 30 are also connected to the network, providing interfaces between the network and further processing devices such as processing device 40 .
The computer 1 may, for example, be a personal computer, a server or a dedicated processing device such as a data logger or controller. In this example it comprises a processor 2 , a program store 4 and a memory 3 . The program store stores instructions defining an operating system and applications that can run on that operating system. The operating system provides means such as drivers and interface libraries by means of which applications can access peripheral hardware devices connected to the computer.
It is desirable for the network interface device to be capable of supporting standard transport protocols such as TCP, RDMA and ISCSI at user level: i.e. in such a way that they can be made accessible to an application program running on computer 1 . Such support enables data transfers which require use of standard protocols to be made without requiring data to traverse the kernel stack. In the network interface device of this example standard transport protocols are implemented within transport libraries accessible to the operating system of the computer 1 .
A typical computer system 1 includes a processor subsystem (including one or more processors), a memory subsystem (including main memory, cache memory, etc.), and a variety of “peripheral devices” connected to the processor subsystem via a peripheral bus. Peripheral devices may include, for example, keyboard, mouse and display adapters, disk drives and CD-ROM drives, network interface devices, and so on. The processor subsystem communicates with the peripheral devices by reading and writing commands and information to specific addresses that have been preassigned to the devices. The addresses may be preassigned regions of a main memory address space, an I/O address space, or another kind of configuration space. Communication with peripheral devices can also take place via direct memory access (DMA), in which the peripheral devices (or another agent on the peripheral bus) transfers data directly between the memory subsystem and one of the preassigned regions of address space assigned to the peripheral devices.
Most modern computer systems are multitasking, meaning they allow multiple different application programs to execute concurrently on the same processor subsystem. Most modern computer systems also run an operating system which, among other things, allocates time on the processor subsystem for executing the code of each of the different application programs. One difficulty that might arise in a multitasking system is that different application programs may wish to control the same peripheral device at the same time. In order to prevent such conflicts, another job of the operating system is to coordinate control of the peripheral devices. In particular, only the operating system can access the peripheral devices directly; application programs that wish to access a peripheral devices must do so by calling routines in the operating system. The placement of exclusive control of the peripheral devices in the operating system also helps to modularize the system, obviating the need for each separate application program to implement its own software code for controlling the hardware.
The part of the operating system that controls the hardware is usually the kernel. Typically it is the kernel which performs hardware initializations, setting and resetting the processor state, adjusting the processor internal clock, initializing the network interface device, and other direct accesses of the hardware. The kernel executes in kernel mode, also sometimes called trusted mode or a privileged mode, whereas application level processes (also called user level processes) execute in a user mode. Typically it is the processor subsystem hardware itself which ensures that only trusted code, such as the kernel code, can access the hardware directly. The processor enforces this in at least two ways: certain sensitive instructions will not be executed by the processor unless the current privilege level is high enough, and the processor will not allow user level processes to access memory locations (including memory mapped addresses associated with specific hardware resources) which are outside of a user-level physical or virtual address space already allocated to the process. As used herein, the term “kernel space” or “kernel address space” refers to the address and code space of the executing kernel. This includes kernel data structures and functions internal to the kernel. The kernel can access the memory of user processes as well, but “kernel space” generally means the memory (including code and data) that is private to the kernel and not accessible by any user process. The term “user space”, or “user address space”, refers to the address and code space allocated by a code that is loaded from an executable and is available to a user process, excluding kernel private code data structures. As used herein, all four terms are intended to accommodate the possibility of an intervening mapping between the software program's view of its own address space and the physical memory locations to which it corresponds. Typically the software program's view of its address space is contiguous, whereas the corresponding physical address space may be discontiguous and out-of-order, and even potentially partly on a swap device such as a hard disk drive.
Although parts of the kernel may execute as separate ongoing kernel processes, much of the kernel is not actually a separate process running on the system. Instead it can be thought of as a set of routines, to some of which the user processes have access. A user process can call a kernel routine by executing a system call, which is a function that causes the kernel to execute some code on behalf of the process. The “current process” is still the user process, but during system calls it is executing “inside of the kernel”, and therefore has access to kernel address space and can execute in a privileged mode. Kernel code is also executed in response to an interrupt issued by a hardware device, since the interrupt handler is found within the kernel. The kernel also, in its role as process scheduler, switches control between processes rapidly using the clock interrupt (and other means) to trigger a switch from one process to another. Each time a kernel routine is called, the current privilege level increases to kernel mode in order to allow the routine to access the hardware directly. When the kernel relinquishes control back to a user process, the current privilege level returns to that of the user process.
When a user level process desires to communicate with the NIC, conventionally it can do so only through calls to the operating system. The operating system implements a system level protocol processing stack which performs protocol processing on behalf of the application. In particular, an application wishing to transmit a data packet using TCP/IP calls the operating system API (e.g. using a send( ) call) with data to be transmitted. This call causes a context switch to invoke kernel routines to copy the data into a kernel data buffer and perform TCP send processing. Here protocol is applied and fully formed TCP/IP packets are enqueued with the interface driver for transmission. Another context switch takes place when control is returned to the application program. Note that kernel routines for network protocol processing may be invoked also due to the passing of time. One example is the triggering of retransmission algorithms. Generally the operating system provides all OS modules with time and scheduling services (driven by the hardware clock interrupt), which enable the TCP stack to implement timers on a per-connection basis. The operating system performs context switches in order to handle such timer-triggered functions, and then again in order to return to the application.
It can be seen that network transmit and receive operations can involve excessive context switching, and this can cause significant overhead. The problem is especially severe in networking environments in which data packets are often short, causing the amount of required control work to be large as a percentage of the overall network processing work.
One solution that has been attempted in the past has been the creation of user level protocol processing stacks operating in parallel with those of the operating system. Such stacks can enable data transfers using standard protocols to be made without requiring data to traverse the kernel stack.
FIG. 2 illustrates one implementation of this. In this architecture the TCP (and other) protocols are implemented twice: as denoted TCP 1 and TCP 2 in FIG. 2 . In a typical operating system TCP 2 will be the standard implementation of the TCP protocol that is built into the operating system of the computer. In order to control and/or communicate with the network interface device an application running on the computer may issue API (application programming interface) calls. Some API calls may be handled by the transport libraries that have been provided to support the network interface device. API calls which cannot be serviced by the transport libraries that are available directly to the application can typically be passed on through the interface between the application and the operating system to be handled by the libraries that are available to the operating system. For implementation with many operating systems it is convenient for the transport libraries to use existing Ethernet/IP based control-plane structures: e.g. SNMP and ARP protocols via the OS interface.
There are a number of difficulties in implementing transport protocols at user level. Most implementations to date have been based on porting pre-existing kernel code bases to user level. Examples of these are Arsenic and Jet-stream. These have demonstrated the potential of user-level transports, but have not addressed a number of the problems required to achieve a complete, robust, high-performance commercially viable implementation.
FIG. 3 shows an architecture employing a standard kernel TCP transport (TCPk).
The operation of this architecture is as follows.
On packet reception from the network interface hardware (e.g. a network interface card (NIC)), the NIC transfers data into pre-allocated data buffer (a) and invokes the OS interrupt handler by means of the interrupt line. (Step i). The interrupt handler manages the hardware interface e.g. posts new receive buffers and passes the received (in this case Ethernet) packet looking for protocol information. If a packet is identified as destined for a valid protocol e.g. TCP/IP it is passed (not copied) to the appropriate receive protocol processing block. (Step ii).
TCP receive-side processing takes place and the destination part is identified from the packet. If the packet contains valid data for the port then the packet is engaged on the port's data queue (step iii) and that port marked (which may involve the scheduler and the awakening of blocked process) as holding valid data.
The TCP receive processing may require other packets to be transmitted (step iv), for example in the cases that previously transmitted data should be retransmitted or that previously enqueued data (perhaps because the TCP window has opened) can now be transmitted. In this case packets are enqueued with the OS “NDIS” driver for transmission.
In order for an application to retrieve a data buffer it must invoke the OS API (step v), for example by means of a call such as recv( ) select( ) or poll( ). This has the effect of informing the application that data has been received and (in the case of a recv( ) call) copying the data from the kernel buffer to the application's buffer. The copy enables the kernel (OS) to reuse its network buffers, which have special attributes such as being DMA accessible and means that the application does not necessarily have to handle data in units provided by the network, or that the application needs to know a priori the final destination of the data, or that the application must pre-allocate buffers which can then be used for data reception.
It should be noted that on the receive side there are at least two distinct threads of control which interact asynchronously: the up-call from the interrupt and the system call from the application. Many operating systems will also split the up-call to avoid executing too much code at interrupt priority, for example by means of “soft interrupt” or “deferred procedure call” techniques.
The send process behaves similarly except that there is usually one path of execution. The application calls the operating system API (e.g. using a send( ) call) with data to be transmitted (Step vi). This call copies data into a kernel data buffer and invokes TCP send processing. Here protocol is applied and fully formed TCP/IP packets are enqueued with the interface driver for transmission.
If successful, the system call returns with an indication of the data scheduled (by the hardware) for transmission. However there are a number of circumstances where data does not become enqueued by the network interface device. For example the transport protocol may queue pending acknowledgements or window updates, and the device driver may queue in software pending data transmission requests to the hardware.
A third flow of control through the system is generated by actions which must be performed on the passing of time. One example is the triggering of retransmission algorithms. Generally the operating system provides all OS modules with time and scheduling services (driven by the hardware clock interrupt), which enable the TCP stack to implement timers on a per-connection basis.
If a standard kernel stack were implemented at user-level then the structure might be generally as shown in FIG. 4 . The application is linked with the transport library, rather than directly with the OS interface. The structure is very similar to the kernel stack implementation with services such as timer support provided by user level packages, and the device driver interface replaced with user-level virtual interface module. However in order to provide the model of a asynchronous processing required by the TCP implementation there must be a number of active threads of execution within the transport library:
(i) System API calls provided by the application
(ii) Timer generated calls into protocol code
(iii) Management of the virtual network interface and resultant upcalls into protocol code. (ii and iii can be combined for some architectures)
However, this arrangement introduces a number of problems:
(a) The overheads of context switching between these threads and implementing locking to protect shared-data structures can be significant, costing a significant amount of processing time.
(b) The user level timer code generally operates by using timer/time support provided by the operating system. Large overheads caused by system calls from the timer module result in the system failing to satisfy the aim of preventing interaction between the operating system and the data path.
(c) There may be a number of independent applications each of which manages a sub-set of the network connection; some via their own transport libraries and some by existing kernel stack transport libraries. The NIC must be able to efficiently parse packets and deliver them to the appropriate virtual interface (or the OS) based on protocol information such as IP port and host address bits.
(d) It is possible for an application to pass control of a particular network connection to another application, for example during a fork( ) system call on a Unix operating system. This requires that a completely different transport library instance would be required to access connection state. Worse, a number of applications may share a network connection which would mean transport libraries sharing ownership via (inter process communication) techniques. Existing transports at user level do not attempt to support this.
(e) It is common for transport protocols to mandate that a network connection outlives the application to which it is tethered. For example using the TCP protocol, the transport must endeavour to deliver sent, but unacknowledged data and gracefully close a connection when a sending application exits or crashes. This is not a problem with a kernel stack implementation that is able to provide the “timer” input to the protocol stack no matter what the state (or existence) of the application, but is an issue for a transport library which will disappear (possibly ungracefully) if the application exits, crashes, or stopped in a debugger.
It would be desirable to provide a system that at least partially addresses one or more of these problems a to e.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, roughly described, there is provided a method for transmitting data by means of a data processing system, the system being capable of supporting an operating system and at least one application and having access to a memory and a network interface device capable of supporting a communication link over a network with another network interface device, the method comprising the steps of: forming by means of the application data to be transmitted; requesting by means of the application a non-operating-system functionality of the data processing system to send the data to be transmitted; responsive to that request: writing the data to be transmitted to an area of the memory; and initiating by means of direct communication between the non-operating-system functionality and the network interface device a transmission operation of at least some of the data over the network; and subsequently accessing the memory by means of the operating system and performing at least part of a transmission operation of at least some of the data over the network by means of the network interface device.
Preferably the operating system is capable of direct communication with the network interface device.
The said direct communication between the non-operating-system functionality preferably bypasses the operating system.
The non-operating-system functionality is preferably implemented by software, most preferably by software running on the data processing system. It may conveniently be a transport library. The non-operating-system functionality most preferably does not require an increase in privilege level in order to accomplish the steps it performs.
The said area of the memory may be mapped to a second area of the memory. The second area of the memory may be accessible to the operating system, most preferably directly accessible, but not directly accessible to the non-operating-system functionality.
The method may comprise, on initiating a transmission operation of data over the network, starting a timer; and if the timer reaches a predetermined value before an acknowledgement is received for that data transmitting a failure message from the network interface device to the data processing system.
The method may comprise, on initiating a transmission operation of data over the network, storing a record of that operation and an indication of the application that was the source of the data; and, on receiving data for that application starting a timer for each record associated with that application; and if such a timer reaches a predetermined value before an acknowledgement is received for that data transmitting a failure message from the network interface device to the data processing system.
Preferably the or each timer is run on the network interface device.
The method may comprise cancelling the timer on receiving an acknowledgement for the data, and wherein the or each failure message is directed to the operating system.
The step of cancelling the timer may comprise the application signalling the entity on which the timer is run in a manner that bypasses the operating system.
The or each failure message is preferably directed to the application that was the source of the data.
The operating system is preferably responsive to failure messages that are directed to applications that are no longer in communication with the network device to perform the said at least part of a transmission operation in respect of data corresponding to the failure message.
According to a second aspect of the present invention, roughly described, there is provided a method for receiving data by means of a data processing system, the system being capable of supporting at least one application and having access to a memory and a network interface device capable of supporting a communication link over a network with another network interface device, the method comprising the steps of: establishing by means of a non-operating-system functionality of the data processing system a channel for reception of data by an application, the channel being associated with an area of the memory; receiving data through that channel by: the network interface device writing received data to the area of the memory; and the application reading received data from that area; and subsequently if the application is unable to communicate with the network device the operating system reading received data from that area.
Preferably the operating system is arranged to automatically read received data from that area on a determination being made that the application is unable to communicate with the network device.
According to a third aspect of the present invention, roughly described, there is provided a method for transmitting data by means of a data processing system, the system being capable of supporting at least one application and having access to a memory and a network interface device capable of supporting a communication link over a network with another network interface device, the method comprising the steps of: forming by means of the application data to be transmitted; passing that data to the network interface device for transmission; transmitting the data by means of the network interface device and, optionally on that transmission, establishing a timer corresponding to the data; and if an acknowledgement is received over the network for the data, cancelling the timer; or if the timer reaches a predetermined value, signalling the operating system by means of the network interface device to indicate that no acknowledgement has been received for the data.
The timer may be started upon establishment of the timer.
When the timer has been established, it may be started upon receipt of data directed to the application that was the source of the data upon whose transmission the timer was established.
The said passing of the data may be performed by a non-operating-system functionality of the data processing system.
The non-operating-system functionality may be a transport library.
The said passing of the data may be performed bypassing the operating system.
The said signalling may comprise applying a failure event to an event queue of the operating system.
According to a fourth aspect of the present invention, roughly described, there is provided a method for transmitting or receiving data by means of a data processing system, the system supporting an operating system and at least one application and having access to a memory and a network interface device capable of supporting a communication link over a network with another network interface device, the method comprising: allocating one or more areas of the memory for use as buffers in the transfer of data between the data processing system and the network interface device; and directly accessing at least one of the areas of the memory by means of the application for at least one of transmission and reception of data by means of the network interface device; and directly accessing the said at least one of the areas of the memory by means of the operating system for at least one of transmission and reception of data by means of the network interface device.
Preferably the method comprises: receiving data from the network by means of the network device; and writing that data to the said at least one of the areas by means of the network device.
Preferably the network device is configured to signal the operating system to access the said at least one of the areas if the application is determined to be unresponsive, and the method comprises performing the said step of directly accessing the said at least one of the areas of the memory by means of the operating system in response to such a signal. The said signal may be an interrupt.
Preferably the network device supports a timer and the method comprises starting the timer to count from a preset initial value when received data is written to the said at least one of the areas, and the application is determined to be unresponsive if the timer reaches a preset final value. Preferably the final value is zero.
Preferably the method comprises the step of setting the initial value and/or the final value by means of the application. Most preferably the final value is zero and only the initial value is set by means of the application.
The method preferably comprises stopping the timer by means of the application on reading received data by means of the application from the said at least one of the areas.
Preferably each of the said steps of directly accessing at least one of the areas of the memory for at least one of transmission and reception of data by means of the network interface device comprises protocol processing of data received from the network by the network interface device and stored in the said at least one of the areas. The protocol processing may comprise one or more of: extracting traffic data from the received data, transmitting an acknowledgement and/or re-transmit message over the network in respect of at least some of the received data, checking sequence values of received data units in the received data, and calculating checksums in respect of the received data. The protocol may be TCP.
Preferably the method comprises: reading data from the said at least one of the areas by means of the network device; and transmitting that data over the network by means of the network device.
Preferably each of the said steps of directly accessing at least one of the areas of the memory for at least one of transmission and reception of data by means of the network interface device comprises storing data for transmission in the said at least one of the areas.
Preferably each of the said steps of directly accessing at least one of the areas of the memory for at least one of transmission and reception of data by means of the network interface device comprises triggering the network interface device to perform the said step of reading data from the said at least one of the areas.
Preferably the network device is configured to signal the operating system to access the said at least one of the areas if the application is determined to be unresponsive, and the method comprises performing the said step of directly accessing the said at least one of the areas of the memory by means of the operating system in responsive to such a signal.
According to a further aspect of the present invention there is provided a system for performing any of the methods described above.
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 is a schematic diagram of a network interface device in use;
FIG. 2 illustrates an implementation of a transport library architecture;
FIG. 3 shows an architecture employing a standard kernel TCP transport with a user level TCP transport;
FIG. 4 illustrates an architecture in which a standard kernel stack is implemented at user-level;
FIG. 5 shows an example of a TCP transport architecture;
FIG. 6 shows the steps that can be taken by the network interface device to filter an incoming TCP/packet;
FIG. 7 illustrates to operation of a server (passive) connection by means of a content addressable memory.
DETAILED DESCRIPTION
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
FIG. 5 shows an example of a TCP transport architecture suitable for providing an interface between a network interface device such as device 10 of FIG. 1 and a computer such as computer 1 of FIG. 1 . The architecture is not limited to this implementation.
The principal differences between the architecture of the example of FIG. 5 and conventional architectures are as follows.
(i) TCP code which performs protocol processing on behalf of a network connection is located both in the transport library, and in the OS kernel. The fact that this code performs protocol processing is especially significant.
(ii) Connection state and data buffers are held in kernel memory and memory mapped into the transport library's address space. The operating system is the owner of those buffers, thus having full control over them, but they can be directly accessed by the application for whose communications they are to be used. This enables the application to transmit and receive data directly through those buffers and to read state data from the corresponding state buffer.
(iii) Both kernel and transport library code may access the virtual hardware interface for and on behalf of a particular network connection
(iv) Timers may be managed through the virtual hardware interface, (these correspond to real timers on the network interface device) without requiring system calls to set and clear them. The NIC generates timer events which are received by the network interface device driver and passed up to the TCP support code for the device.
It should be noted that the TCP support code for the network interface device is in addition to the generic OS TCP implementation. This is suitably able to co-exist with the stack of the network interface device.
In the architecture of FIG. 5 , buffers are allocated in memory on the data processor for use in cooperation with the NIC for the transmission and/or reception of data over the network. In the case of a transmit buffer, which is for use in transmitting data, the NIC is configured for reading data from that buffer and transmitting it over the network. The NIC may automatically read that data and transmit it, or it may be triggered to read the data by an application or the operating system running on the data processor. The trigger can conveniently be an interrupt. In the case of a receive buffer, which is for use in receiving data, the NIC is configured for writing to that buffer data received over the network. The data in the receive buffer may then be read by the application or the operating system and further processed by it.
The buffers are most conveniently owned by the operating system, in the sense that it has control over which entities have access to the buffers, it has allocated and/or created the buffers, and it is responsible for deleting them. However, both the application and the operating system can directly access the buffers for reading data from and writing data to them. The circumstances in which these steps occur will be described below.
In the case of transmission of data, the application will be expected to write data to a buffer for transmission and then trigger the NIC to read from the buffer to transmit that data. In some situations this alone may be sufficient to allow the data to be transmitted successfully over the network. However, the NIC does not perform protocol processing of transmitted or received data. Instead it is performed by the application or the operating system. Therefore if, for instance, the data is not received successfully by the intended recipient the application or the operating system must process acknowledgements, retransmission requests etc. (according to the protocol in use) and cause the NIC to perform retransmission. Normally this can be expected to be done by the application. When the NIC has data such as an acknowledgement message or a timeout for the application it writes that either to a receive buffer and/or an event queue. At the same time it starts a timer running. When the application accesses the data it stops and resets the timer. In that way the NIC knows that the application is responsive. However, if the timer reaches a predetermined value then the NIC determines that the application is unresponsive and signals the operating system, for example by means of an interrupt, to handle the data for the application. This has a number of advantages. First, the transmission of the data can be progressed by the operating system even if the application is busy or has been descheduled. Second, it gives the application the opportunity to intentionally ignore the data, for example by having itself descheduled, once it has placed it on the transmit queue, since the operating system will take over if necessary. Preferably the application controls the length of the timer, for example by setting its initial value. This allows the application to set the timer to suit its priority. The timer is preferably a hardware resource on the NIC to which the application has direct access.
In the case of reception of data, the NIC will receive the data and write it to a receive buffer. When doing so it will set a timer as described above, and preferably inform the application via an event queue. When the application access the data it resets the timer as described above. This again gives the NIC the possibility of determining when the application is unresponsive. Other means such as periodic scans of the data in the buffer by the NIC could be used for the same purpose. If the application is determined to be unresponsive then again the NIC signals the operating system to process the received data. In the case of received data the processing by either the application or the operating system will typically involve protocol processing (e.g. checking of packet sequence numbers, processing checksums, extracting traffic data and/or signalling the NIC to transmit an acknowledgement or retransmission request) and/or removal of data from the buffer for use, typically at user level.
Whilst the buffers are preferably allocated by the operating system, it is convenient for that to be done in response to a request from an application. Thus, if the received data might overflow the available receive buffers for an application, the application can request allocation of further buffers by the operating system. The NIC may signal the application by means of an event if this situation arises, based on pre-stored rules taking into account factors such as the amount of received buffer that remains free. Again it may set a timer when this signalling takes place, and if the application does not respond then the NIC can transmit a request to the operating system for a further receive buffer. The operating system can then allocate that buffer and inform the NIC of it, so that data can continue to be received for the application even if it is unresponsive.
The Effects of this Architecture are as Follows.
(a) Requirement for multiple threads active in the transport Library
This requirement is not present for the architecture of FIG. 5 since TCP code can either be executed in the transport library as a result of a system API call (e.g. recv( )) (see step i of FIG. 5 ) or by the kernel as a result of a timer event (see step ii of FIG. 5 ). In ether case, the VI (virtual interface) can be managed and both code paths may access connection state or data buffers, whose protection and mutual exclusion may be managed by shared memory locks. As well as allowing the overheads of thread switching at the transport library level to be removed, this feature can prevent the requirement for applications to change their thread and signal-handling assumptions: for example in some situations it can be unacceptable to require a single threaded application to link with a multi-threaded library.
(b) Requirement to Issue System Calls for Timer Management
This requirement is not present for the architecture of FIG. 5 because the network interface device can implement a number of timers which may be allocated to particular virtual interface instances: for example there may be one timer per active TCP transport library. These timers can be made programmable (see step iii of FIG. 5 ) through a memory mapped VI and result in events (see step iv of FIG. 5 ) being issued. Because timers can be set and cleared without a system call—without directly involving the operating system—the overhead for timer management is greatly reduced.
(c) Correct Delivery of Packets to Multiple Transport Libraries
The network interface device can contain or have access to content addressable memory, which can match bits taken from the headers of incoming packets as a parallel hardware match operation. The results of the match can be taken to indicate the destination virtual interface which must be used for delivery, and the hardware can proceed to deliver the packet onto buffers which have been pushed on the VI. One possible arrangement for the matching process is described below. The arrangement described below could be extended to de-multiplex the larger host addresses associated with IPv6, although this would require a wider CAM or multiple CAM lookups per packet than the arrangement as described.
One alternative to using a CAM for this purpose is to use a hash algorithm that allows data from the packets' headers to be processed to determine the virtual interface to be used.
(d) Handover of Connections Between Processes/Applications/Threads
When a network connection is handed over the same system-wide resource handle can be passed between the applications. This could, for example, be a file descriptor. The architecture of the network interface device can attach all state associated with the network connection with that (e.g.) file descriptor and require the transport library to memory map on to this state. Following a handover of a network connection, the new application (whether as an application, thread or process)—even if it is executing within a different address space—is able to memory-map and continue to use the state. Further, by means of the same backing primitive as used between the kernel and transport library any number of applications are able to share use of a network connection with the same semantics as specified by standard system APIs.
(e) Completion of Transport Protocol Operations when the Transport Library is Ether Stopped or Killed or Quit.
This step can be achieved in the architecture of the network interface device because connection state and protocol code can remain kernel resident. The OS kernel code can be informed of the change of state of an application in the same manner as the generic TCP (TCPk) protocol stack. An application which is stopped will then not provide a thread to advance protocol execution, but the protocol will continue via timer events, for example as is known for prior art kernel stack protocols.
There are a number newly emerging protocols such as IETF RDMA and iSCSI. At least some of these protocols were designed to run in an environment where the TCP and other protocol code executes on the network interface device. Facilities will now be described whereby such protocols can execute on the host CPU (i.e. using the processing means of the computer to which a network interface card is connected). Such an implementation is advantageous because it allows a user to take advantage of the price/performance lead of main CPU technology as against co-processors.
Protocols such as RDMA involve the embedding of framing information and cyclic redundancy check (CRC) data within the TCP stream. While framing information is trivial to calculate within protocol libraries, CRC's (in contrast to checksums) are computationally intensive and best done by hardware. To accommodate this, when a TCP stream is carrying an RDMA or similar encapsulation an option in the virtual interface can be is enabled, for example by means of a flag. On detecting this option, the NIC will parse each packet on transmission, recover the RDMA frame, apply the RDMA CRC algorithm and insert the CCRC on the fly during transmission. Analogous procedures can beneficially be used in relation to other protocols, such as iSCSI, that require computationally relatively intensive calculation of error check data.
In line with this system the network interface device can also verify CRCs on received packets using similar logic. This may, for example, be performed in a manner akin to the standard TCP checksum off-load technique.
Protocols such as RDMA also mandate additional operations such as RDMA READ which in conventional implementations require additional intelligence on the network interface device. This type of implementation has led to the general belief that RDMA/TCP should best be implemented by means of a co-processor network interface device. In an architecture of the type described herein, specific hardware filters can be encoded to trap such upper level protocol requests for a particular network connection. In such a circumstance, the NIC can generate an event akin to the timer event in order to request action by software running on the attached computer, as well a delivery data message. By triggering an event in such a way the NIC can achieve the result that either the transport library, or the kernel helper will act on the request immediately. This can avoid the potential problem of kernel extensions not executing until the transport library is scheduled and can be applied to other upper protocols if required.
One advantage that has been promoted for co-processor TCP implementations is the ability to perform zero-copy operations on transmit and receive. In practice, provided there is no context switch or other cache or TLB (transmit look-aside buffer) flushing operations on the receive path (as for the architecture described above) there is almost no overhead for a single-copy on receive since this serves the purpose of loading the processor with received data. When the application subsequently accesses the data it is not impacted by cache misses, which would otherwise be the case for a zero copy interface.
However on transmit, a single copy made by the transport library does invoke additional overhead both in processor cycles and in cache pollution. The architecture described above can allow copy on send operations to be avoided if the following mechanisms are, for example, implemented:
(i) transmitted data can be acknowledged quickly (e.g. in a low-latency environment); alternatively
(ii) where data is almost completely acknowledged before all the data in a transfer is sent (e.g. if bandwidth×delay product is smaller than the message size).
The transport library can simply retain sent buffers until the data from them is acknowledged, and data transmitted without copying. This can also be done when asynchronous networking APIs are used by applications.
Even where data copy is unavoidable, the transport library can use memory copy routines which execute non-temporal stores. These can leave copied data in memory (rather than cache), thus avoiding cache pollution. The data not being in cache would not be expected to affect performance since the next step for transmission will be expected to be DMA of the data by the network interface device, and the performance of this DMA operation is unlikely to be affected by the data being in memory rather than cache.
FIG. 6 shows the steps that can be taken by the network interface device described above to filter an incoming TCP packet. At step I the packet is received by the network interface device from the network and enters the receive decode pipeline. At step ii the hardware extracts relevant bits from the packet and forms a filter (which in this example is 32 bits long) which is presented to the CAM. The configuration and number of relevant bits depends on the protocol that is in use; this example relates to TCP/IP and UDP/IP. At step iii, when a CAM match is made it results in an index: MATCH IDX being returned, which can be used to look up delivery information (e.g. the memory address of the next receive buffer for this connection). At step iv this delivery information is fed back to the packet decode pipeline and enables the packet to be delivered to the appropriate memory location.
The selection of the bits and their use to form the filter will now be described.
The network interface device can (preferably in hardware) interrupt or buffer the flow of incoming packets in order that it can in effect pause the network header. This allows it to identify relevant bit sequences in incoming packets without affecting the flow of data. For TCP and/or UDP packets the identification of bit sequences may, for example, be implemented using a simple decode pipeline because of the simple header layout of such packets. This results in a number of fields held in registers.
It is assumed that zero is neither a valid port number nor a valid IP address, and that interfaces in separate processes do not share a local IP address and port pair (except where a socket is shared after a fork( ) command or the equivalent). The latter condition means it is safe to disregard the local IP address when demultiplexing received TCP packets.
For a listening TCP socket only the local IP and port number need be considered, whereas for an established TCP socket remote IP and both port numbers should be considered. The processing performed by the network interface device should therefore (conveniently in hardware) determine whether a received packet is a TCP or a UDP packet, and for TCP packets must inspect the SYN and ACK bits. It can then form a token accordingly, which is looked up in the CAM. The operation of the CAM is illustrated in the following table:
TABLE 1
Bits 0-31
Bits 32-47
Bits 48-63
TCP SYN = 1 & ACK = 0
Local (dest) IP
0
Dest port
TCP otherwise
Remote (src) IP
Src port
Dest port
UDP
Local (dest) IP
Dest port
0
In this table, the first column indicates the type of received packet, and the remaining columns indicate the content of the first 32 bits of the token, the next 16 bits and the final 16 bits respectively. The order of the bits is immaterial provided the same convention is used consistently.
The following table gives examples:
TABLE 2
Packet type
Bits 0-31
Bits 32-47
Bits 48-63
1. TCP listen
192.168.123.135
0
80
2. TCP established
66.35.250.150
33028
80
3. TCP established
66.35.250.150
23
28407
4. UDP
192.168.123.135
123
0
In the examples number 1 illustrates the situation for a local web serve listening on 192.168.123.135:80; number 2 illustrates the situation for a connection accepted by that server from 66.35.250.150:33028; number 3 illustrates a telnet connection to 66.35.250.150, initiated locally; and number 4 illustrates the situation for an application receiving UDP packets on port 123 .
By separating out the situation where TCP SYN=1 & ACK=0, as in the first row of table 1, it can be ensured that such entries match TCP connection request messages (destined for sockets in the LISTEN state), but do not match connection replies (which are destined for sockets in the SYN_SENT state).
Other combinations of zero fields could be used to demultiplex on other fields. For example, demultiplexing could be performed on the ETHER_TYPE field of the Ethernet header.
The logic that determines the configuration of the CAM filter depends on the protocol(s) that is/are to be used. In a practical implementation the CAM could be configured through a virtual interface by means of transport library code, allowing it to be set up dynamically for a particular implementation.
Under the UDP protocol, each network end point specified in a UDP packet can be uniquely identified by the filter as illustrated in table 1.
Under the TCP protocol the unique identity of an endpoint would normally require all host and port fields in order for it to be unambiguously specified. This requirement arises because the TCP protocol definition allows: multiple clients to connect to network endpoints with the same destination host and port addresses, a connection to be initiated from either the client or the server, or a server network endpoint to accept connection requests on a single endpoint and to spawn new network endpoints to handle the data transfer.
The header in such packets is typically 96 bits long. However, constructing a 96-bit filter is inefficient for most commercially available CAMs since they are typically available with widths of 64 or 128 (rather than 96) bits. The following mechanism enables 64 bit filters to be constructed more efficiently. The length of the CAM may be chosen to suit the application. A convenient size may be 16 kb.
(1) If a server (PASSIVE) socket is listening for new connections then all valid incoming TCP packets will have their SYN bit set in their headers in order to indicate a need to synchronise sequence numbers. Packets of that type are identified by the NIC and used to form a filter as illustrated in table 1. Note that the bit layout of the filter means that this filter cannot clash with a UDP endpoint with the same host:port pair because of the zero field placement. Thus the layout of the CAM filter is used to indicate the protocol decode case.
(2) Once a connection is established, valid incoming packets will have their SYN bit set to zero and may be correctly filtered by the logic illustrated in table 1.
Note that in this case the identity of the DEST (destination) host is no longer required in order to identify the correct destination transport library, although the library will in the normal course of reception check this field as part of its normal packet validation procedure. This procedure is illustrated with respect to the server (passive) connection, the contents of the CAM (programmed by the server transport library) and the filters presented to the CAM by the NIC on each packet, as illustrated in FIG. 7 . This involves the following steps:
(a) The transport library allocates a CAM entry via the driver.
(b) The driver programs the hardware through its protected control interface to map the allocated CAM into the address space allocated to the transport library's virtual interface.
(c) The transport library programs the CAM entry via its virtual interface. Where an application is deemed to have insufficient access rights to receive a programmable CAM entry, it can instead be permitted to do so via OS calls.
(ii) A TCP/IP connect packet arrives. Because the SYN bit in the packet header is set to one and the ACK bit in the packet header is set to zero, the network interface device can construct the filter:
{dest host, 0, dest port}
from the bits in the packet header and presents it to the CAM. This causes a match to occur with CAM index X. The network interface device can then look up and in the SRAM to find the base address of the virtual interface: B. The NIC can then deliver the packet to virtual interface B.
As a result of the connect packet, the server application may create another network endpoint to handle the network connection. This endpoint may be within its own or another application context and so may be managed by another transport library. In either case, a network connection can be created which joins:
{dest host, port}
to
{source host, port}
the server programs a new CAM entry with:
{source host, source port, dest port}
(iii) When a packet arrives for the new network connection, it will have its SYN bit set to zero. This causes the NIC to construct a filter:
{source, host source port, dest port}
which when presented to the CAM causes a match index θ to be produced which matches virtual interface σ in the SRAM. It should be noted that σ may be the same as β if the network connection is managed by the same transport library as the server endpoint.
This encoding can similarly be employed for active (client) connections initiated by the host and for all models of communication specified in the TCP and UDP protocol specifications.
One notable benefit of the encoding scheme is that it enables the hardware to determine the address of the virtual interface using only one CAM lookup.
The network interface device preferably also supports a mode of operation in which it simply de-multiplexes packets onto transport libraries, rather than on to network endpoints. This may be beneficial where the device is handling communications between a network and a server which is required to service large numbers (e.g. millions) of connections with the network simultaneously. Examples of this may be high-capacity web server nodes. Two options are available. One option is to store only filters of the form:
{dest host, dest port}
in the CAM. Another option is to employ a ternary CAM which can mask using “don't care” bits. It should be noted that if both modes of operation were to be enabled simultaneously then efficiency may be reduced because two CAM lookups might be required due to the necessity to construct different filters when the SYN bit is set to zero in a received packet. This requirement would be avoided if only one mode were enabled at a time.
The “network interface card” could be embodied as a physical card or it could be implemented in another way, for example as an integrated circuit that is incorporated on to the motherboard of a data processing device.
In this way TCP/IP and UDP/IP packets can both be matched using 64 bits of CAM: as opposed to the 128 bits that would be required if a standard sized CAM using bit-by-bit matching over the whole header were to be used.
Applicants hereby disclose in isolation each individual feature described herein and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of the claims. Applicants indicate that aspects of the present invention may consist of any such individual feature or combination of features. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention. | A method for transmitting data by means of a data processing system, the system being capable of supporting an operating system and at least one application and having access to a memory and a network interface device capable of supporting a communication link over a network with another network interface device, the method comprising the steps of: forming by means of the application data to be transmitted; requesting by means of the application a non-operating-system functionality of the data processing system to send the data to be transmitted; responsive to that request: writing the data to be transmitted to an area of the memory; and initiating by means of direct communication between the non-operating-system functionality and the network interface device a transmission operation of at least some of the data over the network; and subsequently accessing the memory by means of the operating system and performing at least part of a transmission operation of at least some of the data over the network by means of the network interface device. | 6 |
This application is a continuation application of application Ser. No. 14/258,888 filed Apr. 22, 2014 and now abandoned.
This application claims the benefit under 35 USC 119(e) of Provisional Application 61/843,273 filed Jul. 5, 2013.
This invention relates to a method to prevent irritation of deformed toes of a patient.
BACKGROUND OF THE INVENTION
One arrangement of this type is shown in US Application 2013/0079694 published Mar. 28, 2013 by Aquino. Another similar arrangement which is not a subject of a patent application is available on the market by Pedifix of Brewster N.Y.
These and other commercially available toe crest or buttress pads of this type do not address irritation of the shoe against the top of the deformed toes.
SUMMARY OF THE INVENTION
According to the invention there is provided a method to prevent irritation of deformed toes of a patient comprising:
shaping a band having a length to wrap around a plurality of the toes of the patient to form a loop defining a top loop portion for extending across the top of the toes and a bottom loop portion for extending underneath the toes;
the band comprising an elongate tubular member with an exterior tubular wall forming a hollow interior;
the band having a first end at a first end of the tubular member and a second end at a second end of the tubular member;
wherein the second end of the tubular member defines an open mouth at the second end which forms an entrance into the hollow interior of the tubular member into the hollow interior of the tubular member;
passing a first portion of the tubular member at the first end through the entrance defined by the open mouth at the second end so that said first portion extends along the hollow interior from the open mouth to a position spaced from the open mouth of the second end;
causing said first end to emerge through a hole in the exterior wall at said position to define the loop with an end portion of the first end projecting out of said hole in the exterior wall so as to define a tail which can be pulled to tighten the loop;
the top loop portion of the tubular member thus extending between the open mouth at the second end and said hole at said position spaced from the open mouth at the second end with said first portion of the first end extending inside the top portion of the second end to form said top loop portion as a part of the loop which is thicker than the bottom loop portion;
and wrapping the loop around a plurality of toes of the patient so that the top loop portion extends across on top of the plurality of toes and so that the bottom loop portion lies underneath the plurality of toes.
Preferably the tubular member is formed of a fleece material with a pile layer in an inner surface.
Preferably the pile layer is at least partly removed at said connecting portions so that the connecting portions are thinner than the top and bottom portions.
Preferably a resilient padding member is inserted into the hollow interior at least at the bottom portion.
Preferably a resilient padding member is inserted into the hollow interior only at the bottom portion.
Preferably the hole is defined by a slit in the tubular material.
Preferably the top portion is defined by a first end portion at the first end lying inside a second end portion at the second end so that the first and second end portions overlap to define a thicker part of the loop at the top portion.
According to a second aspect of the invention there is provided an apparatus for application to the toes of a patient comprising:
a band comprising a loop having a length to wrap around a plurality of the toes of the patient;
the loop defining a top portion extending across the top of the toes and a bottom portion to extend underneath the toes;
the loop having two connecting portions one at each end each joining the top portion so as to extend between two toes;
the band comprising an elongate tubular member with a hollow interior;
wherein the tubular member is formed of a fleece material with a pile layer on an inner surface.
According to a third aspect of the invention there is provided an apparatus for application to the toes of a patient comprising a band comprising a loop having a length to wrap around a plurality of the toes of the patient;
the loop defining a top portion extending across the top of the toes and a bottom portion to extend underneath the toes;
the loop having two connecting portions one at each end each joining the top portion so as to extend between two toes;
the band comprising an elongate tubular member with a hollow interior;
wherein the top portion is defined by a first end portion at the first end lying inside a second end portion at the second end so that the first and second end portions overlap to define a thicker part of the loop at the top portion.
This modified toe buttress pad of the present invention is adjustable and pads the top the toes so that shoe pressure straightens the toe out while crest pad beneath the toe works the same as the other devices currently on the market.
As stated above, prevents irritation of deformed toes. The invention claimed here solves this problem.
Provides padding and buttressing of deformed toe to prevent irritation or callus formation over the joint or at the tip of the toe.
No padding or “buttressing” of the top of the toe exists in the devices used most commonly today
This modified toe buttress pad is adjustable, and pads the top the toes so that shoe pressure straightens the toe out while crest pad beneath the toe works the same as other devices currently on the market.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:
FIG. 1 is a plan view of the rectangular pad of fleece material which is formed into the pad according to the present invention.
FIG. 2 is a longitudinal cross-sectional view of the components of FIG. 1 .
FIG. 3 is a cross-sectional view along the lines 3 - 3 of FIG. 2 .
FIG. 4 is a cross-sectional view along the lines 4 - 4 of FIG. 2 .
FIG. 5 is a cross-sectional view along the lines 5 - 5 of FIG. 2 .
FIG. 6 is a longitudinal cross-sectional view of the pad of FIG. 2 when folded into the required shape.
In the drawings like characters of reference indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
The pad of the present invention is formed from a rectangular sheet shown in FIG. 1 of a man-made fleece material commonly known as “sherpa fleece”. The rectangular sheet 1 is sewn along adjacent side edges 1 A, 1 B to form a seam 2 which shapes the sheet into a tubular configuration shown in FIG. 2 . A foam pad 3 is inserted into the tubularized sherpa fleece. The fleece has an outer carrying layer 4 and an inner fleece or pile layer 5 .
The apparatus thus provides a loop 20 wrapped around the toes with a tail 21 exposed at one end of the loop. The loop has a length to wrap around a plurality of the toes of the patient. The loop defines a top portion 22 extending across the top of the toes and a bottom portion 23 to extend underneath the toes with two connecting portions 24 , 25 one at each end each joining the top portion so as to extend between two toes. The band has a first end and 7 a second end 8 and comprises an elongate tubular member with a hollow interior. As shown in FIG. 6 , the first end 7 is inserted into the hollow interior of the second end 8 and emerges through a hole 6 adjacent the second end to define the loop 20 with the first end 7 defining the tail 21 which can be pulled to tighten the loop.
As shown in FIG. 1 , the pile layer 5 is at least partly removed at the connecting portions 24 , 25 so that the connecting portions are thinner than the top and bottom portions. A resilient padding member 3 is inserted into the hollow interior at least and preferably only at the bottom portion to provide the support for
In this construction the top portion 22 is defined by a first end portion 26 at the first end 7 lying inside a second end portion 27 at the second end 8 so that the first and second end portions overlap to define a thicker part of the loop at the top portion.
The tube so formed and shown in Figures is folded and inserted into itself and pulled through a slit 6 made in the tube so that the end 7 is wrapped around to the end 8 of the tube and inserted into the end 8 until the end 7 is pulled out of the slit 6 . This provides an end piece 7 A which projects out of the slit 6 so as to be exposed which allows the device to be tensioned for fit and comfort by pulling the end 7 A to increase or decrease the size of the loop encircling the toes of the wearer.
The fleece material creates a padding of the toes dorsally just behind the first joint in the toe to prevent the shoe from rubbing on the bent joint. This pushes down on the toe and helps to straighten the joint of toes that are flexibly contracted. The padding within the tube fills the space under the toes to push the end of the upward thereby straightening the flexible toe or holding the rigidly deformed toe away from the weight-bearing surface. The method of folding and inserting the fleece in to itself and leaving a long tail allows the device to be adjusted to a snug fit about the toes that are encircled. This method is what is unique to this buttress pad.
The fleece is cut into a rectangular shape of the desired dimensions. The fleece is removed in two areas to thin the material that will ultimately lie between the toes. The material is then sewn along one long side to create a tube. The material is then inverted so that the woolly portion or pile layer is inside the tube and the faux suede material is outside. A foam pad is then drawn into the tube to the appropriate position. Near one end of the tubular material a slit 6 is cut about half way through the tube. A grasping tool is then introduced into the slit and exits the tube at the end closest to the slit. The other end of the tube is grasped with the same tool and then drawn into the opposite end and out the slit opening.
Instructions on how to tighten or loosen the device drawn onto the material are provided where the person encircles the deformed or painful toes in the circle formed by the device and pulls on the loose end to tighten it to comfort. Thus user wraps the loop around a plurality of toes T 1 , T 2 , T 3 and T 4 of the patient so that the top loop portion 22 extends across on top of the plurality of toes and so that the bottom loop portion 23 lies underneath the plurality of toes.
Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without department from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense. | A method to prevent irritation of deformed toes of a patient uses an adjustable toe protector formed from a loop of a tubular material with a pile layer on the inside where the length of the loop is adjustable, and pads the top the toes with a double thickness of the material so that shoe pressure straightens the toe out while a crest pad formed by a resilient insert into the tubular material beneath the toe lifts the toes. | 0 |
This application is a continuation of application Ser. No. 905,119, filed on Sept. 9, 1986, now abandoned.
BACKGROUND OF THE INVENTION
The use of a universal product code (UPC) has gained wide acceptance in the retail industries, particularly in the grocery and food industry, although it is not necessarily so limited in use and can be expected to gain even wider acceptance in the future.
The principle involved is the use of a bar code which uniquely identifies each assigned product by a series of lines and spaces of varying widths which may be decoded to a multiple digit representation. The unique identification is the subject of the UPC and has been standardized for a wide range of products.
At the point of sale, the bar code is read by suitable scanning apparatus and the identification utilized for diverse purposes such as inventory control, pricing, etc., all as is well known.
The use of this bar code has imposed severe problems upon the graphics arts industry whose function is to prepare the labeling, etc., which bears the proper bar code symbol for the product in question. That is to say, the printing of the bar code in mass production normally relies upon a flexographic or an offset printing process from which the widths and spacings of the bar code lines and spaces therebetween must be controlled accurately so that the scanning apparatus may read the bar code with high degree of accuracy. This problem is well known and special apparatus has been developed to aid the graphics art processor in maintaining the requisite quality control. Examples of such apparatus are disclosed in the U.S. Pat. No. 4,360,798 of 11/23/82 to Swartz et al, a divisional application of U.S. Pat. No. 4,251,798, and in U.S. Pat. No. 4,396,361, the disclosures of which are incorporated herein by reference. Basically, what apparatus of this type does is to scan the bar code which has been printed and, in controlled and specified fashion derive a "readability measure" criteria therefrom which apprises the user of the quality of the printed bar code from which adjustments, changes, etc., of the printing process may be made. This "readability measure" is referenced the "Percent Decode" or PD and is based upon many factors which may affect the bar code's symbol readability and which in reality is useful only to the printer. A partial list of these factors includes print contrast, uniform barwidth growth, asymmetric barwidth growth, extent and size of any spots or voids, substrate opacity, showthrough, and scatter. In each case, there exists a transition band over which symbol readability is very strongly affected by small changes in the parameter in question. In theory, there should exist for each parameter an absolute cut off point above which readability is 100%, and below which readability is 0%. However, the algorithm upon which the PD is based generates a "conservative" (insofar as the end user is concerned) statistical value for PD from a single scan, and which PD may be of any value, as low as 10%, for example. This anomaly raises many problems in the industry and has little to do with verifying to the ultimate user the quality of the printed bar code with which he must deal.
The anomaly is created by the fact that the bar codes are checked at locations which are not the end user location, and the end user must therefore blindly accept a product which is represented to him as being of proper quality insofar as readability of the bar code is concerned. As noted, the bar code is normally checked at more than one location. First, the printer checks the bar code which he is printing, usually on a quality control basis during the printing process, and it is here that the system is truly operative, because it enables the printer to take corrective measures in response to deteriorating print quality. However, the absolute value of the PD is of little meaning except as to variations and changes therein (i.e., deterioration), especially as concerns the next person processing the labels to which the bar codes are being applied. That is to say, there is no guarantee that the next processor (the processor who applies the labels to the goods, for example) will read the same PD as did the printer, even though he may be using identical equipment. Thus, this next processor must arbitrarily decide what PD he will establish as being sufficient to meet the needs of the end user.
In this way, whether the end user receives his goods directly from the printer or from a processor applying labels to the goods, he is at the mercy of a guessing game. For example, the printer may check the bar code on a quality control sample basis after the printing process and determine, for example, that the PD is 40%, which the printer may decide will be acceptable to the label applier, and that batch of printed material may be checked by the label applier and found to check with a PD of 20%. This packager must decide whether that value of PD is going to meet the needs of the end user.
The variation in PD may be due entirely to the fact that the printer used one apparatus for checking whereas the packager used another apparatus, even though both were identical in make and type of apparatus and thus ostensibly identical as to result. On the other hand, the variation may also be due to the fact that the apparatus attempts to simulate, based upon a single scan, the statistical average of many different scans having different orientations of the bar code relative to the scanning head. Since neither used an apparatus which is the same as the scanning apparatus which will be used at the point of end use, say the checkout counter scanner at a supermarket, the PD determined either by the printer or the subsequent packager has little if any significance to the end user and may, in fact, confer little or no confidence to the end user that the bar code as scanned and determined at the point of use will be adequate for the intended purpose. Since the end user will suffer from any error in reading of the bar code (whether the error is due to an incorrect number being read or no number being read), the current situation is entirely inadequate insofar as the end user is concerned.
To summarize the background of this invention to this point, great difficulty is encountered in the process of printing bar codes, packaging goods with the bar code readable thereon and accurately reading the bar code on the packaged goods at the point of sale. Many variables are involved in this chain of the process. First of all, the readabilty of the bar code at the point of sale depends upon the quality control of the printing process. Secondly, the bar code must be readable at each potential point of sale. Because the scanning laser device at each point of sale may "see" the bar code in its own unique way which may be different from what will be "seen" at any other similar device at any other point of sale, a tremendous difficulty is encountered because of this factor alone.
At any point of sale, two important factors in reading the bar code are critical. First and foremost, the correct UPC number must be read, otherwise the entire purpose of using UPC designation is lost. Secondly and by no means of lesser importance, reading should be successful upon the first scan of the bar code, otherwise the rapidity and proper flow of tallying the results of scanning and reading at the point of sale is seriously affected.
Thus, the mere fact that the bar code is readable on the first scan is not sufficient unless that read corresponds with the correct UPC number which that bar code is supposed to represent. On the other hand, if it takes more than one scan of the bar code to produce a UPC number output, that output must be the correct UPC number. That is to say, it is imperative that the first successful "read" corresponds with the correct UPC number.
The results of quality control at the steps in the chain prior to the ultimate and final scan of the bar code absolutely determines the success of the entire system.
BRIEF SUMMARY OF THE INVENTION
Accordingly, it is of primary concern in connection with this invention to provide method and apparatus for quality control of bar code printing which is directly related to the requirements of the end user and which generates data meaningful to and upon which the end user may rely with confidence.
However, it is to be understood that the invention is not limited to the UPC system and in fact is applicable to any system in which codes or the like are produced, by whatever reproduction method, to identify particular data required by the end user. To this end, the underlying advantage of this invention resides in the ability to allow cooperation among the person or persons supplying the labels and/or packaging or the like and the end user, in order to select the most statistically significant requirement suited to that particular end user.
An object of the invention is to provide a method and apparatus by which the graphics art producer may perceive trends during the printing process which, if left unchecked, could result in reading errors at the point of sale while, at the same time, provides data which is meaningful to the end user.
Another object of the invention is to provide a method and apparatus which provides a consistent and meaningful measurement of bar code readability from the inception of the bar code generating process through any intermediate processors so that quality control of bar code readability may be assured more readily to the ultimate user at the point of sale.
The invention is oriented toward the end user to assure a more significant and meaningful indicator of the performance which may be expected from the bar code labels upon which the end user relies for proper operation of his retail business. It cannot reasonably be expected that bar codes on the consumer items will be read with 100% accuracy if the cost of using this convenience is to be kept within an affordable price. However, the end user requires an indicator which relates to a parameter which allows him to calculate the potential business loss due to incorrect bar code reading. Such an indicator is provided by this invention. With the apparatus of this invention, the indicator is the percentage of correct bar code "reads" which he may expect to obtain with the items with which he is supplied. If used by the printer, the percent accuracy is determined and this accuracy may be passed on to the processor who provides the end user with the finished product, properly labeled and having a reliable bar code label thereon. When the processor in turn uses the apparatus of this invention, he too will be in possession of a reliable and meaningful percentage figure in which the end user may place trust.
The currently available equipment is informative principally and almost solely to the operator of printing equipment and requires temporal sampling in order to provide meaningful results to the printer for controlling the printing run. That is, as noted above, the currently available equipment indicates trends in the form of PD readings which are occurring during the printing process and which, if left unchecked, ultimately will result in such a degradation of the bar codes being printed that they will be useless. The end user is not interested in the PD because it has no real meaning to him.
The invention as disclosed and claimed herein provides an indication of the percentage of "misreads" (i.e., either an inability to read or an incorrect read) which may be expected at the user end of the chain. To this end, the scanner utilized in this invention is a flattop scanner of the type used by the end user, in combination with a dedicated processor, keyboard, display and suitable software. The dedicated computer is interfaced with the scanner so as to provide on/off control as well as to receive and decode the electronic output of the scanner to identify numerically the bar code passed through the scanner's laser beam. A keyboard is electronically linked to the computer to permit entry of commands as well as numerical identification of the symbol to be scanned. The digital display is electronically linked to the computer to provide visual identification of the UPC number corresponding to the bar code scanned, to display comparison of this number with the correct number and, by command from the keyboard, to provide statistical analysis regarding the symbols which have been scanned. A strip printer may be linked with the computer to provide print-out of the statistical analysis. The software program contains the logic to control the laser scanner, decode the electronic output from the scanner to provide the UPC numerical identification of the bar code scanned, to store the correct code or codes, to provide comparison of the scanned symbol with the correct symbol in memory, and to cause the various displays.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a diagrammatic illustration of a system according to this invention;
FIGS. 2a and 2b represent a logic flow diagram according to one embodiment of the invention; and
FIGS. 3a and 3b represent another logic flow diagram according to another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1 at this time, reference character 10 indicates a flat top laser scanner which preferably is a Spectra physics, Inc. model 8610 or other store quality helium-neon laser scanner having equal bar code sensitivity. The serial output of the scanner 10 is coupled through the I/O device 12 having bus connection with the microprocessor 14 or equivalent computer. The computer components include the program ROM 16, the data RAM 18 and the non-volatile storage 20. The parallel I/O device 22 electronically links the computer system to the display unit 24 which may be of conventional nature and to the conventional keyboard unit 26. The printer 28 which may optionally be provided is coupled with the serial I/O device 12. All of the above components are available as items of commerce and will be well understood by those skilled in the art.
It is, however, pointed out that the scanning unit 10 should be of the type equivalent to a so-called store unit, that is, it should be a unit identical to or closely resembling the type of scanner which the end user will employ. This assures that the results of the program hereinafter described will most closely approximate the results which the end user will experience so that the statistical analysis provided by the invention will be meaningful to such end user. In this regard, the end user will know the percentage of "misreads" which he can tolerate and the supplier of his goods may thus assure, with this invention, that the requisite percentage is supplied to the end user. The printer may also employ this invention to obtain not only data meaningful to him concerning whether the printing process is degrading, but also he may pass on to the next processor data which, in turn, is meaningful to the end user.
The end user will require a percentage of "good" reads which typically may prove to be in the range of about 91-95%. This percentage is established by cooperation among the printer, the packager and the end user and this is easily assured by the invention. It is to be noted, as explained hereinbefore, that the particular percentage may be different for different end users and it is in this particular aspect that the invention derives a significant advantage over other systems which are available in the prior art.
The software logic flow will be apparent from FIG. 2. Whenever the system is powered up, the scanner is reset as at 30 and the main menu is displayed as indicated at 31. The main menu reads: ENTER COMMAND: 1/SETUP, 2/GO, 3/RST SCNR, */DISABLE, #/ENABLE LASER. Assuming the operator wishes to test a new bar code symbol which has never been tested before, "1" (for setup) is pressed on the keyboard and in response thereto, the setup menu is displayed as indicated by the logic at 34. Otherwise, the logic loops as indicated at 33 awaiting a keystroke entry. The setup menu reads: ENTER SCAN CODE. PRESS "0" TO ENTER CODE FROM SCANNER. The operator thus has two options, he may manually enter the scan code from the keyboard or he may enter the code by passing a bar code known to be correct over the scanner. If the former, the logic at 35 responds at the line 36 to the entry "0" to cause the scanner input to be displayed as at 37 and the main menu is redisplayed as at 39 and the system loops as at 40, awaiting the next keystroke. If, for some reason the display does not indicate the correct UPC number on the display, or the operator has changed his mind, "3" is pressed to reset the scanner and clear memory as at 58 and redisplay the main menu as at 59 and loop awaiting the next keystroke.
If the setup was correct and the desired number was displayed as at 38, when the main menu is redisplayed as at 39, the operator next enters the keystroke "2" and the test information is displayed as at 47. This display initially reads: TEST CODE A021900027256 NO. READ 0; CURRENT NO. ERROR 0, assuming that the correct UPC number was as indicated, i.e., A021900027256. The operator then proceeds to begin the test procedure by passing the bar code labels over the scanner. The serial input from the scanner is read as at 48 and the logic at 49 causes the first input to be compared with the correct UPC number. If correct, the "yes" answer at 50 causes the scan count to be updated as at 51. The display will now read: TEST CODE A021900027256 NO. READ 1; CURRENT NO. READ 0 unless the operator has pressed a key during the scan input, in which case the logic at 54, 56, 57 loops the system back to the condition awaiting an initial keystroke as at 32. If this operator error logic was not activated, the system loops as at 55 awaiting the next scan input.
For purposes of this description, it will be assumed that for the particular end user in question, it has been established by and among the printer, packager and end user that the number of bar codes which must be tested is thirteen and that the number of correct reads must be at least 91%. Using this arbitrary example, assume that at the end of the thirteen scans, the display reads: TEST CODE A021900027256 NO. READ 13, CURRENT A073040154156 NO. ERROR 1. The "CURRENT A073040154156" indicates that this number, rather than the correct number A021900027256 was read to produce the "NO. ERROR 1". The percentage statistical analysis corresponds to a percentage in excess of the required 91% (12/13×100). Accordingly, the test has indicated that the batch of goods from which the statistical sample was selected may be represented as passing the end user's requirements.
The logic at 42 responds to the first keystroke during "setup" after pressing the "1" key, so long as this first key is not "0", and displays this key as the first entry from the keyboard as the desired UPC number to be tested. The logic then loops back as indicated at 43, 44 awaiting the next keyboard entry. When all of the desired keyboard entries have been made, the operator enters the "#" key which causes the logic, at 43, 45 to store all digits in RAM, redisplay the main menu and loop back to the logic at 32.
The logic at 60, responsive to the "*" key after the logic at 32 is present, turns off the laser scanner and loops back to the logic at 32. This prevents spurious input from the scanner during a manual input of the desired UPC number and, after the desired UPC number has been entered manually (the logic has now looped back to 32), the "#" key may be pressed to reactivate the scanner to begin a test.
The logic flow illustrated in FIGS. 3a and 3b differs from that described above with relation to FIGS. 2a and 2b principally in that if entry of the correct bar code is made by scanning a correct symbol, the logic rather than returning to the main menu as described above, goes directly to the test mode. Also, the first number scanned during the test mode will be displayed rather than waiting for the tenth scan. Thus, instead of reading "TEST CODE A021900027256 NO. READ 1; CURRENT NO. READ 0" as noted above, the display will be TEST CODE A021900027256 NO. READ 1; CURRENT A021900027256 NO. ERROR 0.
For convenience, primed reference characters are employed in FIGS. 3a and 3b which correspond generally with their unprimed counterparts in FIGS. 2a and 2b. | Method and apparatus for reading, by an end user scanner, the UPC number designated by a bar code printed on or associated with a predetermined number of packages or containers for or containing goods to determine the percentage of correctly read UPC numbers with reference to the predetermined number of readings. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Provisional Application No. 62/056,162 filed Sep. 26, 2014, the contents of which are hereby incorporated by reference
FIELD
[0002] The present subject matter relates generally to methods and apparatuses for treating an organic feed. More specifically, the present invention relates to methods for treating a cumene and alpha-methylstyrene stream using a caustic wash column having an integrated water wash section.
BACKGROUND
[0003] The present subject matter relates to the preparation of a cumene feed for a cumene oxidation process. More specifically, it relates to a process and apparatus for the preparation of a cumene feed for cumene oxidation from a fresh cumene and alpha-methylstyrene stream. It is important that the caustic wash column is stable. It is also important that caustic does not carry over from the caustic wash column which deactivates the downstream alpha-methylstyrene hydrogenation catalyst. Currently, downstream equipment is used to remove caustic that is carried over from the caustic wash column. For example, a caustic settler may be used after a caustic wash column to ensure the caustic is thoroughly removed from the feed before it enters a downstream unit. However, it would be preferable to improve the caustic wash column itself so that it may be stable and limit the caustic carry over without the need for additional equipment.
[0004] Accordingly, it is desirable to develop methods and apparatuses for a process for removing organic acids using an integrated caustic wash column. Furthermore, other desirable features and characteristics of the methods and apparatuses will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawing and this background.
SUMMARY
[0005] Methods and apparatuses for producing hydrocarbons are provided. In an exemplary embodiment, a method includes treating an organic feed using a caustic wash column having an integrated water wash section.
[0006] In one approach, a process for treating an organic feed includes a process for treating an organic feed by introducing a feed stream from a feed tank containing at least one organic acid compound into a caustic wash section of a caustic wash column. Then an aqueous caustic scrubbing solution is introduced into the caustic wash column. A water stream is also introduced to a water wash section of the caustic wash column. Contacting of the feed through an aqueous caustic scrubbing solution removes the organic acid from the feed. The process removes spent aqueous caustic and organic acid solution from the caustic wash column. The process also removes an organic product from the water wash section of the caustic wash column having a reduced level of organic acid relative to the feed stream.
[0007] In another approach, the apparatus for treating an organic feed includes a caustic wash column having a lower portion, an intermediate portion, and an upper portion. In one example, the line for introducing the feed from a feed tank containing at least one organic acid compound enters the caustic wash column in the intermediate portion of the caustic wash column. A line for introducing an aqueous caustic scrubbing solution is also connected to the caustic wash column. In one example, the line for introducing an aqueous caustic scrubbing solution may enter the caustic wash column in the intermediate portion of the caustic wash column. A line for introducing a water stream into the water wash section of the caustic wash column is connected to the column. In one example, the line for introducing the water stream into the column may enter the column in the upper portion of the column. The column may include jetting trays within the column for contacting of the feed through an aqueous caustic scrubbing solution to remove the organic acid from the feed. A line for removing spent aqueous caustic and organic acid solution from the caustic wash column is connected to the bottom of the column. A line for removing an organic product from the water wash section of the caustic wash column wherein the organic product has a reduced level of organic acid relative to the feed stream is connected the top of the column.
[0008] An advantage of the methods and apparatuses for the continuous preparation of a cumene feed is that it provides a more stable system.
[0009] Another advantage of the methods and apparatuses for the continuous preparation of a cumene feed is that it limits caustic carry over.
[0010] Another advantage of the methods and apparatuses for the continuous preparation of a cumene feed is that it consolidates the amount of units needed to restrict caustic carry over.
[0011] A further advantage of the methods and apparatuses for the continuous preparation of a cumene feed is that the feed tank accounts for any upsets from upstream vessels.
[0012] Yet another advantage of the methods and apparatuses for the continuous preparation of a cumene feed is that the caustic supplied for the process does not have to be diluted, but can be directly used in the caustic wash column.
[0013] Additional objects, advantages and novel features of the examples will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following description and the accompanying drawing or may be learned by production or operation of the examples. The objects and advantages of the concepts may be realized and attained by means of the methodologies, instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWING
[0014] The FIGURE depicts one or more implementations in accord with the present concepts, by way of example only, not by way of limitations. In the FIGURE, like reference numerals refer to the same or similar elements.
[0015] The FIGURE is an illustration of a process for treating an organic feed using a caustic wash column having an integrated water wash section.
DETAILED DESCRIPTION
[0016] The following detailed description is merely exemplary in nature and is not intended to limit the application and uses of the embodiment described. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
[0017] The further description of the process of this invention is presented with reference to the attached FIGURE. The FIGURE is a simplified flow diagram of a preferred embodiment of this invention and is not intended as an undue limitation on the generally broad scope of the description provided herein and the appended claims. Certain hardware such as valves, pumps, compressors, heat exchangers, instrumentation and controls, have been omitted as not essential to a clear understanding of the invention. The use and application of this hardware is well within the skill of the art.
[0018] The overall process to which this invention pertains concerns the oxidation of a secondary alkylbenzene, for example, isopropylbenzene (cumene) isobutylbenzene, isoamylbenzene, 1-methyl-4-isopropylbenzene, p-diisopropylbenzene, p-diisobutylbenzene, 1-isopropyl-4-isobutylbenzene, cyclohexyl benzene, and the like, to form the corresponding hydroperoxide, i.e., isopropylbenzene hydroperoxide, isobutylbenzene hydroperoxide, isoamylbenzene hydroperoxide, 1-methyl-4-isopropylbenzene hydroperoxide, p-diisopropylbenzene hydroperoxide, p-diisobutylbenzene hydroperoxide, 1-isobutyl-4-isopropylbenzene dihydroperoxide, cyclohexylbenzene hydroperoxide, and the like. The present invention is particularly directed to a process for the preparation of a cumene feed for cumene oxidation from a fresh cumene stream and a recycle cumene stream containing trace quantities of at least one organic acid compound. The organic acid compound is selected from the group consisting of formic acid, acetic acid, benzoic acid, propionic acid, butyric acid and phenol.
[0019] The various embodiments described herein relate to methods and apparatuses for treating an organic feed using a caustic wash column having an integrated water wash section. In accordance with the present invention, the vertical, countercurrent contacting zone is preferably contained in a vessel such as a column 30 , which has packing, trays or other convenient means to provide countercurrent liquid-liquid extraction. In one example, jetting trays may provide contacting of the organic phase through an aqueous caustic scrubbing solution to remove the organic acid from the organic phase. The contacting zone is preferably operated at a pressure from about atmospheric (0 kPa gauge) to about 150 psig (1035 kPa gauge) and a temperature from about 41° F. (5° C.) to about 140° F. (60° C.). However, other operating temperatures and pressures may be used in the practice of the present process, but preferably so long as the liquid phase is maintained.
[0020] Turning to the FIGURE, a feed tank 10 supplies a feed 20 to the caustic wash column 30 . In the example shown in the FIGURE, the feed tank 10 ensures that the caustic sufficiently contacts the hydrocarbon mixture because it acts as a place holder for the feed 20 , instead of allowing the feed 20 to flow directly from the upstream unit to the caustic wash column 30 . The feed 20 in the example shown in the FIGURE includes cumene, alpha-methylstyrene, and phenol. However, it is contemplated that the feed may contain other hydrocarbon mixtures. For example, it is contemplated that the feed may contain acetone, organic acids, benzene, hydroxyacetone, 2-MBF, acetaldehyde, propionaldehyde, and heavy alkyphenols.
[0021] The caustic wash column 30 comprises a lower portion 40 , an intermediate portion 50 , and an upper portion 60 . The feed 20 enters the caustic wash column 30 in the intermediate portion 50 . The caustic solution 80 enters the caustic wash column 30 in the intermediate portion 50 of the caustic wash column 30 . However, it is contemplated that the feed 20 and caustic solution 80 may enter the caustic wash column 30 at other portions of the column 30 .
[0022] The aqueous caustic solution which is introduced into the caustic/hydrocarbon contacting zone preferably contains from about 1 to about 20 wt % caustic. While various caustic solutions that are known in the art for treating a cumene feed may be used, the preferred caustic solution is an aqueous sodium hydroxide solution. Make-up caustic solutions may have concentrations from about 5 to about 50 wt % caustic. In the example shown in the FIGURE, the sodium hydroxide may comprise 45 wt % of the caustic solution. The concentration of the aqueous caustic solution used is related to the amount of organic acid that is being removed from the feed 20 .
[0023] A water stream 70 enters the caustic wash column 30 in the upper portion 60 of the column 30 . A mesh blanket 100 may also be located in the upper portion 60 of the caustic wash column 30 . As the organic feed 20 moves up the caustic wash column 30 the organic acid in the organic feed 20 becomes entrained with the caustic 80 and then is contacted with the water stream 70 . Within the column 30 , an acid base reaction occurs. The caustic reacts with the phenol to make water and sodium phenate. The organic feed passes through the mesh blanket 100 once before it reaches the top of the column 30 . The mesh blanket coalesces any small amounts of water or caustic, therefore minimizing the amount of water exiting the top of the column 30 . Once the organic feed reaches the top of the column 30 , a clean, mainly caustic free organic phase exits the top of the column 30 in the product stream 90 .
[0024] A portion of the product stream 90 may be recycled back to the feed 20 via line 110 . The recycled product 110 may be admixed with the feed 20 before entering the caustic wash column 30 , or the recycled product feed 110 and the feed 20 may enter the caustic wash column 30 at distinct inlets.
[0025] A second product stream 120 exits from the bottom of the column 30 . The second product stream 120 comprises water, caustic, and sodium phenate.
[0026] It should be noted 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 may be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages.
SPECIFIC EMBODIMENTS
[0027] While the following is described in conjunction with specific embodiments, it will be understood that this description is intended to illustrate and not limit the scope of the preceding description and the appended claims.
[0028] A first embodiment of the invention is an apparatus for treating an organic feed comprising a line for introducing a feed stream from a feed tank containing at least one organic acid compound into a caustic wash section of a caustic wash column; a line for introducing an aqueous caustic scrubbing solution into the caustic wash column; a line for introducing a water stream into a water wash section of the caustic wash column; jetting trays within the column for contacting of the feed through an aqueous caustic scrubbing solution to remove the organic acid from the feed; a line for removing spent aqueous caustic and organic acid solution from the caustic wash column; and a line for removing an organic product from the water wash section of the caustic wash column wherein the organic product has a reduced level of organic acid relative to the feed stream. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the organic feed comprises cumene and alpha-methylstyrene. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the organic acid compound is phenol. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the apparatus removes 10-25 wt % of phenol. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the aqueous caustic scrubbing solution contains sodium hydroxide. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the aqueous scrubbing solution contains 40-50 wt % of sodium hydroxide. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the organic product is a mixture comprising of 75-90 wt % cumene and alphamethylstyrene. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the caustic wash column is operated at a pressure from about 0.1 to 3.0 kg/cm2(g) and a temperature from about 30 to 60° C. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, further comprising a mesh blanket for coalescing of any water and aqueous caustic scrubbing solution. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, further comprising jetting trays for contacting of the organic phase through an aqueous caustic scrubbing solution to remove the organic acid from the organic phase. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the caustic wash section comprises a plurality of trays. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the first embodiment in this paragraph, wherein the water wash section comprises a plurality of trays.
[0029] A second embodiment of the invention is an apparatus for treating an organic feed comprising a line for introducing a feed stream comprising cumene and alphamethylstyrene from a feed tank into a caustic wash column having a caustic wash section and a water wash section; a line for introducing a scrubbing solution comprising 45 wt % sodium hydroxide into the caustic wash column; a line for introducing a water stream into a water wash section of the caustic wash column; jetting trays within the column for contacting of the feed through an aqueous caustic scrubbing solution to remove the organic acid from the feed; a line for removing water, sodium hydroxide, and sodium phenate from the lower portion of the caustic wash column; and a line for removing 10-25 wt % phenol from the feed. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph, wherein the caustic wash column is operated at a pressure from about 0.1 to 3.0 kg/cm2(g) and a temperature from about 30 to 60° C. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph, further comprising a mesh blanket for coalescing of any water and aqueous caustic scrubbing solution. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph, wherein jetting trays provide contacting of the organic phase through an aqueous caustic scrubbing solution to remove the organic acid from the organic phase. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph, wherein the caustic wash section comprises a plurality of trays. An embodiment of the invention is one, any or all of prior embodiments in this paragraph up through the second embodiment in this paragraph, wherein the water wash section comprises a plurality of trays.
[0030] Without further elaboration, it is believed that using the preceding description that one skilled in the art can utilize the present invention to its fullest extent and easily ascertain the essential characteristics of this invention, without departing from the spirit and scope thereof, to make various changes and modifications of the invention and to adapt it to various usages and conditions. The preceding preferred specific embodiments are, therefore, to be construed as merely illustrative, and not limiting the remainder of the disclosure in any way whatsoever, and that it is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
[0031] In the foregoing, all temperatures are set forth in degrees Celsius and, all parts and percentages are by weight, unless otherwise indicated. | The present subject matter relates to methods and apparatuses for the continuous preparation of a cumene feed for a cumene oxidation process. More specifically, the subject matter relates to a process for passing a cumene alpha-methylstyrene stream through a caustic wash column having an integrated water wash section for the removal of organic acids. | 1 |
FIELD OF THE INVENTION
[0001] This invention relates to disinfection of fluids with ultraviolet radiation, particularly to a disinfection reactor capable of efficiently irradiating such fluids.
BACKGROUND
[0002] Disinfection, as applied in water and wastewater treatment, is a process by which pathogenic microorganisms are inactivated to provide public health protection. Chlorination has been the dominant method employed for disinfection for almost 100 years. However, it is no longer the disinfection method automatically chosen for either water or wastewater treatment because of the potential problems associated with disinfection by-products and associated toxicity in treated water. Ultraviolet (UV) irradiation is a frequent alternative chosen to conventional chlorination. Since UV radiation is a nonchemical agent, it does not yield disinfectant residual. Therefore, concerns associated with toxic disinfectant residuals do not apply. In addition, UV disinfection is a rapid process. Little contact time (on the order of seconds rather than minutes) is required. The result is that UV equipment occupies little space when compared to chlorination and ozonation.
[0003] The responses of microorganisms to UV irradiation are attributable to the dose of radiation to which they are exposed. The UV dose is defined as the product of radiation intensity and exposure time. As a result of turbulent flow conditions and three-dimensional spatial variations in UV intensity, continuous-flow UV systems deliver a broad distribution of UV does. Principles of reactor theory can be used to demonstrate that this distribution of doses leads to inefficient use of the UV energy emitted within these systems. Furthermore, the theoretical upper limit on UV reactor performance coincides with a system which accomplishes the delivery of a single UV dose (i.e., a dose distribution which can be represented by a delta function). Optimal dose distribution is difficult to achieve in currently used UV disinfection systems.
[0004] An average dose does not accurately describe the disinfection efficiency of a full-scale UV system. UV intensity is a function of position. The intensity of UV radiation decreases rapidly with distance from the source of radiation. Exposure time is not a constant either. The complex geometry of UV systems dictates complex hydrodynamic behavior as well, with strong velocity gradients being observed. Coincidentally, fluid velocity is generally highest in areas of lowest intensity. This creates a situation in which some microorganisms are exposed to a low UV intensity over a comparatively short period of time, thereby allowing them to “escape” the system with a relatively low UV dose. This represents a potentially serious process limitation in UV systems. For example, if 1% of the microorganisms received doses lower than the lethal level, then the maximum inactivation achievable by the system is 99%, no matter what actual average dose was delivered.
[0005] Non-uniform distribution of UV doses in systems indicates that UV radiation is applied inefficiently. While UV overdose apparently presents no danger in terms of finished water composition, it does increase operating and capital costs. Therefore, it is desirable to have a system which incorporates the effects of hydrodynamic behavior and the UV intensity field to provide for complete disinfection.
[0006] Mathematical modeling of UV reactors has been used to improve reactor design and predict microbial inactivation. Do-Quang et al (1997) discussed the use of CFD modeling of a vertical lamp open channel UV reactor to improve microbial inactivation. Blatchley et al (1997) proposed a method of particle tracking for calculating the dose distribution in an open channel horizontal lamp UV reactor. That model took into consideration both the hydrodynamics of the system and the intensity field.
[0007] The above models were based on low-pressure lamp systems installed in wastewater that have a single germicidal wavelength output at 254 nm. CFD modeling is helpful in assessing reactor design with in-line drinking water reactors since the hydraulic residence time in these systems is less than about 1 second and the spacing between lamps is larger and non-uniform in comparison to most low-pressure lamp wastewater systems.
SUMMARY OF THE INVENTION
[0008] This invention relates to an apparatus for irradiating fluids with UV including a reactor vessel having a fluid inlet, a fluid outlet and a reaction chamber, a plurality of UV lamps extending across the reaction chamber and substantially perpendicularly to an axis extending between the fluid inlet and the fluid outlet, an upper and a lower fluid diverter extending across the reaction chamber substantially parallel to the lamps and positioned downstream of at least one upstream UV lamp, wherein the upper and lower fluid diverters are positioned to direct fluids toward at least one UV lamp downstream of the upstream UV lamp.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a schematic view of fluence rate distribution (in mW/cm′) of a 20-inch reactor at 90% UVT.
[0010] FIG. 2 is a schematic view of a model at 1.4 m/s entry velocity at the cross-section 5 cm from the reactor centerline of a closed reactor.
[0011] FIG. 3 is a graph showing head loss through one reactor versus flow rate.
[0012] FIG. 4 is a schematic showing the UV dose received by the 39 particles at the outlets of a closed reactor.
[0013] FIG. 5 is a graph showing the UV dose distribution at 6.27 MGD and 0.046/cm water absorbance.
[0014] FIG. 6 is a side elevational view of a closed UV reactor in accordance with aspects of the invention, partly taken in section.
[0015] FIG. 7 shows further detail of the UV reactor of FIG. 6 with respect to UV lamps contained therein.
[0016] FIG. 8 is a front elevational view, taken partially in section of the UV reactor of FIG. 6 .
[0017] FIG. 9 is a side elevational view of another UV reactor, also partially taken in section, in accordance with aspects of the invention.
DETAILED DESCRIPTION
[0018] It will be appreciated that the following description is intended to refer to specific embodiments of the invention selected for illustration in the drawings and is not intended to define or limit the invention, other than in the appended claims.
[0019] CFD can be used as a design tool to improve microbial inactivation while minimizing head loss in the reactor. Head loss is important in UV drinking water reactors since most UV systems in a water plant are located downstream of filtration and before clearwell where there is little head to spare. Low head loss allows a UV reactor to be installed in more water plants without the need for modifications such as adding pumps or lowering the level of the clearwell leading to other issues such as the reduction of CT.
[0020] A closed UV reactor 10 is shown in FIGS. 6-8 . The reactor includes a fluid inlet 12 , a fluid outlet 14 and a reaction chamber 16 . The fluid inlet 12 , fluid outlet 14 and reaction chamber are substantially round in shape, although other shapes such as oval, for example, can be used. Four UV lamps 18 extend substantially parallel to one another and, as especially shown in FIGS. 6 and 7 , are arranged to form the four corners of a square. The lamps 18 also are positioned substantially perpendicularly to axis A extending between inlet 12 and outlet 14 . Each UV lamp 18 is surrounded by and sealed within a quartz jacket (not shown), the structure and arrangement of which is well known to those of ordinary skill in the art.
[0021] A UV sensor 20 is positioned adjacent each UV lamp to accurately assist in the detection and determination of UV emissions from the respective UV lamps.
[0022] An upper fluid diverter 22 is located in the reaction chamber and oriented at about a 45° angle out of horizontal. A lower fluid diverter 24 is similarly positioned at the bottom of the reaction chamber 16 . Lower diverter 24 , in this case, is located substantially vertically below upper diverter 22 . An L-shaped center diverter 26 is positioned halfway between upper and lower diverters 22 and 24 and, in this case, is positioned vertically below upper diverter 22 and above lower diverter 24 . The L-shape of diverter is formed by a pair of legs angled at about 90° with respect to one another. Each leg is angled about 45° out of horizontal. The diverters 22 , 24 and 26 are positioned downstream of at least one of the upstream UV lamps and are further positioned to direct fluids towards at least one UV lamp downstream of the upstream UV lamp. There is no particular need or benefit to placing diverters (or other obstructions) upstream of or at the location of the upstream UV lamp(s). Thus, in this case, lamps 18 A and B are upstream lamps and lamps 18 C and D are downstream lamps.
[0023] Referring specifically to FIG. 7 , a reactor end plate 28 is sealed to UV reactor 10 and is utilized to position the lamps 18 and diverters 22 , 24 and 26 in the desired location. Sensors 20 are positioned substantially vertically oriented with respect to each other and are also aligned in the upstream to the downstream direction to provide consistency in UV data collected by the respective censors.
[0024] FIG. 9 shows another embodiment that employs six lamps 18 , lettered “A-F”, as preceding from upstream to downstream. UV reactor 10 of FIG. 9 also includes a fluid inlet 12 and fluid outlet 14 and a reaction zone 16 . Reactor 10 also includes diverters 22 and 24 , but not 26 in this case. As in the other embodiment, diverters 22 and 24 are preferably angled at about 45° out of horizontal to effectively divert fluids toward a UV lamp located nearest the uppermost and lowermost portions of reaction chamber 16 , respectively. Sensors 20 are positioned to detect UV from each of the lamps 18 .
[0025] The fluence rate distribution in a 6-lamp reactor layout ( FIG. 9 ) is shown in FIG. 1 . As described earlier, the intensity in the reactor decreases rapidly with distance from the source of radiation and is non-uniform. In order to eliminate high fluid velocities in low areas of UV intensity, CFD experiments were conducted as shown in FIG. 2 . As can be seen in FIG. 2 , the deflectors in the reactor direct the flow from the low intensity areas along the reactor wall into the high intensity areas near the UV lamps. These deflectors in the reactor result in a narrow calculated dose distribution with no low UV dose areas evident as shown in FIG. 5 . Also, there are no significant overdose areas evident in the reactor resulting in energy inefficiency. One of the drawbacks of baffles or deflectors is that they increase the head loss in the system. The deflectors herein provide the benefit of eliminating the low dose areas in the reactor while minimizing the cross-sectional area they take up in the reactor. This deflector design led to the minimal head loss in the 6-lamp reactor as shown in FIG. 3 .
[0026] Although this invention has been described in connection with specific forms thereof, it will be appreciated that a wide variety of equivalents may be substituted for the specified elements described herein without departing from the spirit and scope of this invention as described in the appended claims.
[0027] For example, reactor 10 can be made from a wide variety of materials, both ferrous and non-ferrous, so long as they provide the appropriate strength, corrosion and UV resistance characteristics. Stainless steel is especially preferred. A wide variety of UV lamps, quartz jackets and devices to seal the lamps with respect to the jackets may also be employed. Sensors of varying types can be used as conditions merit. Also, the materials used for the diverters can vary as appropriate, so long as they are sufficiently strong, have appropriate corrosion and UV resistance. Although angles out of horizontal of about 45° are especially preferred, other angles may be employed to suit specific positioning of UV lamps 18 . Angles less than 90° are preferred.
[0028] Although we have selected two embodiments for illustration that contain four and six lamps, other numbers of lamps can be utilized, either more or less. Especially preferred alternatives include two-lamp reactors and eight-lamp reactors, although more could be employed as warranted. As noted above, variations on the number of lamps, angles of placement of the diverters and the like should be carefully selected to ensure that head loss characteristics are maintained as desired. | An apparatus for irradiating fluids with LV including a reactor vessel ( 10 ) having a fluid inleT ( 12 ), a fluid outlet ( 14 ) and a reaction chamber ( 16 ); a plurality of UV lamps ( 18 a - d ) extending across the reaction chamber ( 16 ) and substantially perpendicularly to an axis (A) extending between the fluid inlet ( 12 ) and the fluid outlet ( 14 ); an upper fluid diverter ( 22 ) and a lower fluid diverter ( 24 ) extending across the reaction chamber ( 16 ) substantially parallel to the lamps ( 19 a - d ) and positioned downstream of at least one upstream UV lamp ( 18 a, b ), wherein the upper and lower fluid diverters ( 22, 24 ) are positioned to direct fluids toward at least one UV lamp ( 18 c, d ) downstream of the upstream UV lamp ( 18 a, b ). | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority benefit from U.S. provisional patent application 61/441,915 filed 11 Feb. 2011.
FIELD
[0002] The present disclosure relates to a pullrod connection to a journal of a rotating member.
BACKGROUND
[0003] In FIG. 1 , an opposed-piston, opposed-cylinder (OPOC) engine 10 is shown isometrically. An intake piston 12 and an exhaust piston 14 reciprocate within each of first and second cylinders (cylinders not shown to facilitate viewing pistons). Exhaust pistons 14 couple with a journal (not visible) of crankshaft 20 via pushrods 16 . Intake pistons 12 couple with two journals (not visible) of crankshaft 20 via pullrods 18 , with each intake piston 12 having two pullrods 18 . The first and second cylinders in which the pistons reciprocate are parallel but offset from each other in the Y direction due to pullrods 18 associated with the cylinder shown front and leftward displaced in a negative Y direction with respect to pullrods 18 associated with the cylinder shown rear and rightward. Pushrods 16 are similarly situated with respect to each other. It is cost effective that all four pullrods 18 are identical in design and the two pushrods 16 are the same. However, a disadvantage of such an offset design is that the engine is wider than it would otherwise be if the two cylinders could be collinear. A torque is introduced due to the offset of the two cylinders.
[0004] One alternative to overcome the offset cylinders is a forked rod, such as is described in U.S. Pat. No. 1,322,824, invented by F. Royce. By employing a forked rod/blade rod configuration within the engine of FIG. 1 , the length of the journal (or crank pin) can be reduced. Also, the cylinders are collinear. The width of the engine can be reduced and the unbalanced forces are reduced. However, a disadvantage of such a configuration is that the piston in one cylinder couples with the crankshaft by a forked rod and the corresponding piston in the opposing cylinder couples with the crankshaft by a blade rod thereby increasing part count for the engine. A system for coupling the rods to the crankshaft is desired which allows common parts to be used in the two cylinder, such as is possible with the configuration shown in FIG. 1 , while allowing collinear cylinders, such as that shown U.S. Pat. No. 1,322,824.
SUMMARY
[0005] Disclosed herein is a connecting-rod assembly that achieves a low part count while allowing for an in-line arrangement of cylinders. Such assembly includes: a cylindrical journal, first and second bearing shell portions placed on the journal, a first bearing cap placed on the first bearing shell portion and a second bearing cap placed on the second bearing shell portion. The first bearing cap has a concave surface that forms a cylindrical portion that mates with a convex surface of the first bearing shell portion. The first bearing cap has first and second fingers extending outwardly from a first end of the cylindrical portion with a gap of a predetermined width between the first and second fingers. The first bearing cap has a third finger extending outwardly from a second end of the cylindrical portion. The second bearing cap has a concave surface that forms a portion of a cylinder that mates with a convex surface of the second bearing shell portion. The second bearing cap has first and second fingers extending outwardly from a first end of the cylindrical portion with a gap of the predetermined width between the first and second fingers. The second bearing cap has a third finger extending outwardly from a second end of the cylindrical portion. The third finger of the first bearing cap engages with the first and second fingers of the second bearing cap and the third finger of the second bearing cap engages with the first and second fingers of the first bearing cap.
[0006] An orifice of a predetermined diameter is defined in each of the first, second, and third fingers of both the first and second bearing caps and the orifices are located near tips of the finger. The orifices are substantially parallel to the central axis of the journal.
[0007] The assembly further includes a first connecting rod with an outside edge of the connecting rod shaped roughly as an elongated isosceles triangle. The first connecting rod includes: a first corner adapted to couple with a reciprocating element, a second corner having a single tab of the predetermined width through which an orifice of the predetermined diameter is defined, and a third corner having double tabs each defining an orifice of the predetermined diameter. The double tabs are separated by a gap of the predetermined width and the first connecting rod is placed over the second bearing shell portion with the single tab meshing with the first and second fingers of the first bearing cap and the third finger of the first bearing cap meshing with the double tabs of the first connecting rod. A first pin is inserted through the orifice in the single tab and the orifices in the first and second fingers of the first bearing cap. A second pin is inserted through the orifices in the double tabs and the orifice in the third finger of the first bearing cap.
[0008] The assembly further includes a second connecting rod with an outside edge of the connecting rod shaped roughly as an elongated isosceles triangle. The second connecting rod includes: a first corner adapted to couple with a reciprocating element, a second corner having a single tab of the predetermined width through which an orifice of the predetermined diameter is defined, and a third corner having double tabs each defining an orifice of the predetermined diameter. The double tabs are separated by a gap of the predetermined width. The second connecting rod is placed over the first bearing shell portion with the single tab of the second connecting rod meshing with the first and second fingers of the second bearing cap and the third finger of the second bearing cap meshing with the double tabs of the second connecting rod. A third pin is inserted through the orifice in the single tab of the second connecting rod and the orifices in the first and second fingers of the second bearing cap. A fourth pin is inserted through the orifices in the double tabs of the second connecting rod and the orifice in the third finger of the second bearing cap.
[0009] The first pin has a radial groove proximate an end of the first pin and the second pin each has a radial groove proximate an end of the second pin with a first snap ring coupled to the groove in the first pin and a second snap ring coupled to the groove in the second pin.
[0010] Alternatively, a snap ring is inserted into an annular groove defined in the second finger; a snap ring is inserted into an annular groove defined in the third finger; a snap ring is inserted in an annular groove defined into a first of the double tabs; and a snap ring is inserted into an annular groove defined in a second of the double tabs.
[0011] In another alternative, a counterbore of a counterbore diameter is collinear with the orifice in the second finger. A snap ring is inserted into an annular groove defined in the second finger. A counterbore of the counterbore diameter is collinear with the orifice in one of the double tabs. A snap ring is inserted into an annular groove defined in the one of the double tabs. A body of the first and second pins is of the predetermined diameter and heads of the first and second pins are of the counterbore diameter.
[0012] According to some embodiments, first and second through-hole orifices are defined in the first bearing shell portion near an end of the first bearing shell portion and first and second threaded orifices are defined in the second bearing shell portion near an end of the second bearing shell portion. A first screw is inserted through the first through-hole orifice of the first bearing shell portion and threads of the first screw engaged with the first threaded orifice of the second bearing shell portion. A second screw is inserted through the second through-hole orifice of the first bearing shell portion and threads of the second screw engaged with the second threaded orifice of the second bearing shell portion.
[0013] According to some embodiments, the first bearing shell portion and the second bearing shell portion have fingers extending outwardly from at least one end of each the first and second bearing shell portions. An orifice is defined in the fingers with an axis of the orifice being substantially parallel to a central axis of the journal. The fingers of the first and second bearing shell portions are enmeshed to form a box joint with a dowel pin inserted through the orifices in the enmeshed fingers.
[0014] In some embodiments, the first bearing cap has a cylindrical concave surface and a pin extending radially from the cylindrical concave surface. The first bearing shell portion has a cylindrical convex surface having an aperture defined in the cylindrical convex surface and the pin engages with the aperture. The aperture is substantially evenly spaced between the ends of the first bearing shell portion and the aperture may be a groove extending less than 30 degrees of the circumference of the first bearing shell portion. The second bearing cap has a cylindrical concave surface and a pin extending radially from the cylindrical concave surface. The second bearing shell portion has a groove defined in a cylindrical convex surface associated with the second bearing shell portion. The groove associated with the second bearing shell portion extends less than the circumference of the second bearing shell portion and the pin associated with the second bearing cap engages with the groove associated with the second bearing shell portion. Relative rotational motion of the first bearing shell portion with respect to the first bearing shell cap is substantially prevented by the pin engaging with the aperture.
[0015] The first bearing shell portion has first and second oil holes located roughly 60 degrees from first and second ends of the first bearing shell portion, respectively; an inner surface of the first bearing shell portion has a first annular oil groove extending from the first end of the first bearing shell portion to the first oil hole; and the inner surface of the first bearing shell portion has a second annular oil groove extending from the second end of the first bearing shell portion to the second oil hole. A third oil groove defined in an outer surface of the first bearing shell portion extends between the first and second oil holes. Alternatively, a third oil groove is defined in a portion of the concave surface of the first bearing cap and the portion extends from first oil hole to the second oil hole of the first bearing shell portion at all relative positions of the first bearing cap with respect to the first bearing shell portion.
[0016] The first bearing cap has an oil hole through the cylindrical portion with the oil hole of a larger diameter at an end of the hole proximate the concave surface. The pin is hollow and the hollow pin is inserted in the oil hole.
[0017] According to an alternative embodiment, a threaded hole is defined in each end of the first, second, and third fingers with the threaded holes being substantially parallel. A first connecting rod having a rod portion, a journal connection portion, and a piston connection portion is provided with the journal connection portion having two parallel flanges that are substantially perpendicular with respect to an axis of the rod portion. A first of the flanges has two through holes and a second of the flanges has a single through hole. The journal connection portion further includes a surface facing away from the rod portion that defines a portion of a concave cylinder. A first bolt is placed within one of the two through holes and coupled with threads in the threaded hole defined in the first finger of the first bearing cap. A second bolt is placed within the other of the two through holes and coupled with threads in the threaded hole defined in the second finger of the first bearing cap. A third bolt is placed within the single through hole and coupled with the threads in the threaded hole defined in the third finger of the first bearing cap. A second connecting rod is similarly fixed to the second bearing cap.
[0018] The first bearing cap has two parallel bearing surfaces facing inwardly with the two parallel bearing surfaces extending away from the ends of the cylindrical portion of the first bearing cap.
[0019] The first connecting rod has two parallel bearing surfaces facing outwardly with the bearing surfaces of the first bearing cap bearing against the bearing surfaces of the first connecting rod.
[0020] The second bearing cap has two parallel bearing surfaces facing inwardly with the two parallel bearing surfaces extending away from the ends of the cylindrical portion of the second bearing cap; and the second connecting rod has two parallel bearing surfaces facing outwardly with the bearing surfaces of the second bearing cap bearing against the bearing surfaces of the second connecting rod.
[0021] In some embodiments, the journal is a portion of a crankshaft of an internal combustion engine with the journal predominantly rotating in one direction. In alternative embodiments, the journal oscillates back and forth without always rotating.
[0022] The third finger of the bearing caps has a width as measured along an axis parallel to a central axis of the journal substantially equal to the predetermined width of the gap between the first and second fingers of the bearing cap. In some embodiments, the first, second, and third fingers are substantially parallel.
[0023] Also disclosed is a journal-connecting rod assembly having a first connecting rod having a first corner adapted to couple with a reciprocating element, a second corner having a single tab of the predetermined width, and a third corner having double tabs. A first bearing cap has a concave surface that forms a cylindrical portion that mates with a convex surface of the first bearing shell portion, the first bearing cap has first and second fingers extending outwardly from a first end of the cylindrical portion, the first bearing cap has a third finger extending outwardly from a second end of the cylindrical portion, the third finger of the first bearing cap is slid between the double tabs at the third corner of the first connecting rod, and the single tab at the second corner of the first connecting rod is slid between the first and second fingers of the first bearing cap. A second connecting rod has a first corner adapted to couple with a reciprocating element, a second corner having a single tab, and a third corner having double tabs. The assembly further includes a second bearing cap having a concave surface that forms a cylindrical portion that mates with a convex surface of the first bearing shell portion. The second bearing cap has first and second fingers extending outwardly from a first end of the cylindrical portion and a third finger extending outwardly from a second end of the cylindrical portion. The third finger of the second bearing cap is slid between the double tabs at the third corner of the second connecting rod. The single tab at the second corner of the second connecting rod is slid between the first and second fingers of the second bearing cap. The assembly may further include a journal and first and second roller bearing portions each including multiple needle bearings nested within a bearing race. The first and second roller bearing portions coupled to the journal wherein an inner, concave portion of the cylindrical portion of the first and second bearing caps ride upon the needle bearings. Alternatively, the assembly includes a journal. An inner, concave portion of the cylindrical portion of the first and second bearing caps mate with an outer convex surface of the journal.
[0024] Also disclosed is a method to assemble two connecting rods to a single journal including: placing first and second portions of a bearing shell onto the journal; placing a first bearing cap over one of the two bearing portions wherein the first bearing cap has first and second fingers extending away from a top of the first bearing cap and a third finger extending away from a bottom of the first bearing cap; and meshing a second bearing cap with the first bearing cap. The second bearing cap has first and second fingers extending away from the bottom of the second bearing cap and a third finger extending away from a top of the second bearing cap. The meshing entails the third finger of the first bearing cap sliding into a gap between the first and second fingers of the second bearing cap and the third finger of the first bearing cap sliding into a gap between the first and second fingers of the second bearing cap.
[0025] The method may also include: placing a first connecting rod onto an outside surface of the second bearing cap, inserting a first bolt into a first through hole in the first connecting rod, engaging threads in a first bolt hole in the first finger of the first bearing cap with threads of the first bolt, inserting a second bolt into a second through hole in the first connecting rod, engaging threads in a second bolt hole in the second finger of the first bearing cap with threads of the second bolt, inserting a third bolt into a third through hole in the first connecting rod, engaging threads in a third bolt hole in the third finger of the first bearing cap with threads of the third bolt, placing a second connecting rod onto an outside surface the first bearing cap, inserting a fourth bolt into a first through hole in the second connecting rod, engaging threads in a first bolt hole in the first finger of the second bearing cap with threads of the fourth bolt, inserting a fifth bolt into a second through hole in the second connecting rod, engaging threads in a second bolt hole in the second finger of the second bearing cap with threads of the fifth bolt, inserting a sixth bolt into a third through hole in the second connecting rod, and engaging threads in a third bolt hole in the third finger of the second bearing cap with threads of the sixth bolt. In some embodiments, the first bearing cap has a pin extending outwardly and an outer surface of the first portion of the bearing shell defines an aperture. The method may include engaging the pin with the aperture to limit the movement of the first bearing cap with respect to the first portion of the bearing shell.
[0026] In some alternative embodiments, the method includes placing a first connecting rod onto an outside surface of the second bearing cap. A first end of the first connecting rod is adapted to couple with a reciprocating element; a first corner on a second end of the first connecting rod has a single tab having an orifice; a second corner on a second end of the first connecting rod has two tabs each having an orifice with the single tab meshing with the second and third fingers of the second bearing cap and the first finger of the second bearing cap meshing with the two tabs. The method may further include inserting a first pin through the orifice in the single tab and the orifices in the second and third fingers of the second bearing cap, inserting a second pin through the orifices in the two tabs and the orifice in the first finger of the second bearing cap, installing a first snap ring proximate the first pin, and installing a second snap ring proximate the second pin. The second connecting rod may be similarly assembled onto the journal.
[0027] Also disclosed is a journal and connecting rod assembly, including a cylindrical journal, first and second bearing portions coupled onto the journal, a first bearing cap placed on the first bearing portion, the first bearing cap having a concave surface that mates with a convex surface of the first bearing portion, and a second bearing cap placed on the second bearing portion. The second bearing cap has a concave surface mating with a convex surface of the second bearing portion. The first bearing cap has first and second fingers extending outwardly from a first end of a cylindrical portion of the first bearing cap and a third finger extending outwardly from a second end of the cylindrical portion of the first bearing cap. The second bearing cap has first and second fingers extending outwardly from a first end of a cylindrical portion of the second bearing cap and a third finger extending outwardly from a second end of the cylindrical portion of the second bearing cap. The third finger of the first bearing cap engages with the first and second fingers of the second bearing cap and the third finger of the second bearing cap engages with the first and second fingers of the first bearing cap. Each of first, second, and third fingers of first and second bearing caps has an orifice defined therein. The assembly may further include a first connecting rod having three orifices adapted to align with the three holes in the first, second, and third fingers of the first bearing cap and a second connecting rod having three orifices adapted to align with the three holes in the first, second, and third fingers of the second bearing cap. Axes of the three orifices in the first and second connecting rods and axes of the holes in the first, second, and third fingers of the first and second bearing caps are substantially parallel to a central axis of the journal. The orifices are aligned with the associated holes. Pins are inserted into the aligned orifices and holes. Alternatively, axes of the three orifices in the first and second connecting rods axes of the holes in the first, second, and third fingers of the first and second bearing caps are substantially perpendicular to a central axis of the journal and roughly parallel with the first second and third fingers of the associated bearing cap. The orifices are aligned with the associated hole and the holes in the bearing cap are threaded and bolts are inserted into the orifices and engaged with the threads in the holes.
[0028] The assembly may further include a longitudinal oil hole defined in the journal roughly parallel with an axis of rotation of the journal, a radial oil hole defined in the journal fluidly coupling the longitudinal oil hole and a surface of the journal, oil holes defined in the first and second bearing shell portions with the oil holes located approximately one-third of the distance between ends of the bearing shell portions, an oil groove on a concave surface of the first bearing shell portion extending circumferentially between an oil hole and a proximate end of the first bearing shell portion, an oil groove on a concave surface of the second bearing shell portion extending circumferentially between an oil hole and a proximate end of the second bearing shell portion, an oil groove on a convex surface of the first bearing shell portion between oil holes, and
[0029] an oil groove on a convex surface of the second bearing shell portion between oil holes.
[0030] The assembly may have a pin inserted into an orifice in the concave surface of the first bearing cap with the pin extending inwardly and an aperture defined in the first bearing portion with the pin indexed with the aperture to restrict relative movement between the first bearing portion and the first bearing cap with the pin indexed with the aperture substantially prevents relative movement and the second bearing cap is unpinned.
[0031] In some embodiments, the aperture is a first groove and the assembly further has a pin inserted into an orifice in the concave surface of the second bearing cap and a second groove defined in the second bearing portion with the pin indexed with the aperture. The first and second grooves extend a predetermined length on a convex surface of the first and second bearing portions so as to restrict relative movement of the first bearing portion with respect to the first bearing cap and relative movement of the second bearing portion with respect to the second bearing cap.
[0032] An advantage provided by embodiments described above, is that a single, common bearing is provided for two pullrods, i.e., to accommodate two pistons thereby allowing a more compact engine. Furthermore, the friction is reduced. The friction is the same during pulling, but for the portion of the rotation with no pulling, there is no friction, thereby reducing the overall friction of the engine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 illustrates an example configuration of an opposed-piston, opposed-cylinder engine in an isometric view;
[0034] FIG. 2 is an isometric view of a connecting rod to crankshaft journal connection according to an embodiment of the present disclosure;
[0035] FIGS. 3 and 4 show a connecting rod and a bearing cap related to the components illustrated in FIG. 2 ;
[0036] FIG. 5 is an exploded view of a connecting rod/bearing cap system according to an embodiment of the present disclosure;
[0037] FIG. 6 is an illustration of the connecting rod of FIG. 5 ;
[0038] FIG. 7 is an alternative connecting rod;
[0039] FIG. 8A illustrates the bearing shell portions of FIG. 5 ;
[0040] FIG. 8B illustrates an alternative embodiment to secure the bearing shell portions;
[0041] FIG. 9 illustrates an alternative roller bearing embodiment;
[0042] FIGS. 10 and 11 illustrated various embodiments for pinning the pullrod with the bearing cap;
[0043] FIGS. 12 , 14 , and 17 illustrate the arrangement of the pistons and connecting rods in different angles of crank rotation;
[0044] FIGS. 13 and 15 show a detail of the crank connection at two crank positions according to one embodiment for pinning a shell bearing portion;
[0045] FIGS. 16 and 18 show a detail of the crank connection at two crank positions according to one embodiment for restricting motion of the shell bearing portions; and
[0046] FIGS. 19 and 20 are flowcharts of the assembly processes for two embodiments of the disclosure.
DETAILED DESCRIPTION
[0047] As those of ordinary skill in the art will understand, various features of the embodiments illustrated and described with reference to any one of the Figures may be combined with features illustrated in one or more other Figures to produce alternative embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. Those of ordinary skill in the art may recognize similar applications or implementations whether or not explicitly described or illustrated.
[0048] In FIG. 2 an isometric view of a journal 96 with a central axis 99 that coincides with a center 97 of journal 96 is shown. Journal 96 is coupled to two connecting rod portions 100 a and 100 b via respective bearing caps 102 a and 102 b . Two bearing shell portions 98 a , 98 b are included between bearing caps 102 a , 102 b and journal 96 . Each of bearing caps 102 a and 102 b has a first finger 104 a ( 104 a not visible in FIG. 2) and 104 b , a second finger 106 a and 106 b , and a third finger 108 a ), and 108 b . First finger 104 a and second finger 106 a of bearing cap 102 a mesh with third finger 108 b of bearing cap 102 b . A gap between first finger 104 a and second finger 106 a is substantially equal to the width of third finger 108 b . Furthermore, the width of first finger 104 a is approximately equal to the width of second finger 106 a . Connecting rod 100 a has a first flange 110 a and a second flange 112 a ; connecting rod 100 b has first and second flanges 110 b , 112 b . Through holes 116 b and 118 b are provided in flange 112 b ; through hole 122 b is provided in flange 110 b . Bolts 124 b , 126 b are slid into through holes 116 b and 118 b , respectively, and engaged with threaded holes 128 b , 130 b in fingers 104 b and 106 b , respectively. A bolt 132 b is slid into through hole 122 b and engaged with a threaded hole 134 b.
[0049] In FIG. 4 , a single pullrod 100 is shown having a first flange 110 with a hole 122 and a second flange 112 with two orifices 116 and 118 (as the two orifices are in line, only one is shown in phantom). A concave surface 136 forms a portion of a cylinder. Pullrod 100 also has a rod portion with a small end portion 142 at one end. Pullrod 100 also has bearing surfaces 144 . Bearing surfaces 144 lie in planes parallel to each other and are located at ends of concave surface 136 . Bearing surfaces 144 face outwardly. Pullrod 100 can be described as having a piston connection portion (alternatively referred to as small end portion 142 ), journal connection portion 143 , and rod portion 145 between the two connection portions. FIG. 4 illustrates a bearing cap 102 that can be coupled to pullrod 100 . Of first and second fingers 104 and 106 , only one is visible in this view. On the other end of bearing cap 102 is third finger 108 . Threaded hole 134 aligns with through hole 110 of pullrod 100 . Threaded holes 128 and 130 align with through holes 116 and 118 of pullrod 100 . Bearing cap 102 has a concave surface 146 that forms a portion of a cylinder. Extending from the ends of concave surface 146 are bearing surfaces 148 which are parallel and face each other. When bearing cap 102 is assembled with pullrod 100 , bearing surfaces 144 of pullrod 100 bear against bearing surfaces 148 of bearing cap 102 . Bearing surfaces 144 support bearing cap 102 from crushing as it is pulled at fingers 104 , 106 , and 108 . If bearing cap 102 is even slightly deformed, it becomes out of round and increases friction in the journal.
[0050] An alternative embodiment of a pullrod/bearing cap system 158 is shown in FIG. 5 in an isometric, exploded view. Pullrods 160 a and 160 b have small ends 162 a and 162 b adapted to couple with reciprocating elements, such as pistons. Pullrod 160 a has a first tab 164 a and a second tab 166 a separated by a gap 168 a of a predetermined width. Pullrod 160 a has a third tab 170 a . Each of first, second, and third tabs 164 a , 166 a , and 170 a has orifices: 174 a , 176 a , and 180 a , respectively, each of a predetermined diameter. Pullrods 160 a and 160 b have concave surfaces 172 a and 172 b that form a portion of a cylinder. Pullrod 160 a and 160 b have bearing surfaces that are in contact with bearing surfaces of the bearing caps. Most of these bearing surfaces are not visible in FIG. 5 , except for bearing surface 182 b of pullrod 160 b . A corner of bearing surface 180 b is visible on the far side of third tab 170 b ; another bearing surface (not visible) is provided between first and second tabs 164 b and 166 b . Pullrod 160 a has similar bearing surfaces as pullrod 160 b , but none of such bearing surfaces on pullrod 160 a are visible in this view. These bearing surfaces are provided to prevent crushing of the bearing cap, as will be described in more detail below.
[0051] Also shown in FIG. 5 is a bearing cap 184 a that has first and second fingers 186 a and 188 a separated by a gap of the predetermined width (substantially the same width as the gap between the first and second tabs, i.e., gap between 164 a and 166 a ; and gap between 164 b and 166 b ). Bearing cap 184 a also has a third finger 190 a having a width of the predetermined width. Fingers 186 a , 188 a , 190 a , 186 a , 188 a , and 190 a each have an orifice, 192 a , 194 a , 196 a , 192 a , 194 a , and 196 a , respectively located substantially parallel to a central axis of the journal (not shown in FIG. 5 ). First and second fingers 186 a and 188 a are substantially the same width; third finger 190 a is approximately twice the width of first finger 186 a . The gap between first and second fingers 186 a and 188 a is substantially the same as the width of third finger 190 a . Bearing cap 184 a has three bearing surfaces: two bearing surfaces 198 a on first and second fingers 186 a and 188 a and one bearing surface (not visible) on third finger 190 a . The bearing surface on third finger 190 a is substantially parallel with and faces toward bearing surfaces 198 a on first and second fingers 186 a and 188 a . Bearing cap 184 b is identical to bearing cap 184 ; however, as oriented in FIG. 5 , only one of three bearing surfaces 198 b is visible, i.e., bearing surface 198 b associated with third finger 190 b.
[0052] Bearing surfaces 198 a and 198 b of bearing caps 184 a and 184 b bear against bearing surfaces 182 a and 182 b of pullrods 160 a and 160 b , respectively. Bearing caps 184 a and 184 b have concave surfaces 199 a and 199 b that are portions of a cylinder. Also shown in FIG. 5 are bearing shell portions 200 a and 200 b . Concave surfaces 172 a and 172 b of pullrods 160 a and 160 b mate with convex surfaces 197 a ( 197 a not visible in FIG. 5) and 197 b of bearing caps 184 a and 184 b , respectively. Concave surfaces 199 a and 199 b of and bearing caps 184 a and 184 b mate upon convex surfaces 201 a and 201 b of bearing shell portions 200 a and 200 b , respectively.
[0053] To assemble the connecting rod assembly, bearing shell portions 200 a and 200 b are placed over a cylindrical journal (not shown in FIG. 5 ). Bearing shell portions 200 a and 200 b are coupled via four screws 202 , shown in FIG. 5 . Bearing caps 184 a and 184 b are placed over bearing shell portions 200 a and 200 b with fingers of the bearing caps meshing: first and second fingers of one bearing cap meshing with the third finger of the other bearing cap and vice versa. One of the pullrods is placed over one of the bearing caps such that orifices in the tips of the pullrods align with orifices in fingers of the bearing cap. A pin 204 is placed through the aligned orifices, one at the top and one at the bottom, and secured with snap rings 206 , one at each end of pins 204 , as per the embodiment in FIG. 5 . The other pullrod is similarly secured to the other bearing cap.
[0054] One advantage of embodiments of the present disclosure is that pullrod 160 a is identical to pullrod 160 b just as bearing cap 184 a is identical with bearing cap 184 b . In FIG. 5 , pullrod 160 a is “upside down” with respect to pullrod 160 b such that the corner of pullrod 160 b has the corner with single tab 170 b pointing upwardly and pullrod 160 a has the corner with single tab 170 a pointing downwardly in FIG. 5 . In the embodiment in FIG. 3 , pullrods 100 a and 100 b are identical; and bearing caps 102 a and 102 b are identical. By having identical parts, the number of unique parts to assemble an engine is reduced thereby reducing cost of the product.
[0055] Another advantage of the assembly shown in FIG. 5 is that pins 204 are in shear. These can be made rather smaller in diameter than other connection schemes. Smaller pins facilitate smaller orifices in the pullrod and the bearing cap thereby allowing smaller tabs and smaller fingers, respectively. The mass of the parts can be reduced and the assembly is more compact. Reducing mass of the rotating components present many advantages: less unbalanced force, reduced cost due to reduced material, reduced size of related parts, e.g., mounts, bearings. Yet a further advantage is reduced machining and assembly steps, thereby further reducing cost of manufacture.
[0056] In FIG. 6 , it can be seen that pullrod 160 is shaped roughly in the shape of an isosceles triangle 210 with small end portion 162 at one corner of the triangle. Other edges 212 on the long sides of the roughly triangular shape are thicker than the center portion of pullrod 160 . Pullrod 160 can be considered to include a piston connection portion (which is alternatively the small end portion 162 ), a journal connection portion 213 , and a rod portion 214 between the two connection portions. In another embodiment shown in FIG. 7 , pullrod 220 forms a lattice in the central region.
[0057] An isometric drawing of the bearing shell portions in an exploded view is shown in FIG. 8A . Bearing shell portions 200 a and 200 b are fastened by screws 202 that pass into through holes 222 a which are large enough to accommodate the head of screws 202 and into through holes 223 a and then into threaded holes (not visible in this view) associated with bearing shell portion 200 b , similar to threaded holes 224 a . Lubrication grooves 225 are provided in the concave surfaces 211 a and 221 b in the bearing shell caps 200 a and 200 b . Oil supply to lubrication grooves 225 is shown in more detail in FIGS. 13 , 15 , 16 , and 18 . Oil supplied to oil grooves 225 passes through oil holes 227 to oil grooves 226 formed in the convex surfaces 201 a and 201 b (oil groove 226 in bearing cap 200 a is not visible in FIG. 8A ).
[0058] In an alternative embodiment illustrated in FIG. 8B , bearing shell portions 230 and 232 have interlocking fingers at one end with holes through the fingers so that a pin 234 may be inserted through the holes. In one embodiment, shell bearing portions 230 and 232 are installed on a journal of a crankshaft with the crankshaft having weights on either side of the journal so that pin 234 cannot fall out. In other embodiments without features holding the pin in place, the pin has a head on one end and a snap ring on the other end. Alternatively, the pin is secured by snap rings in an internal fashion. Any suitable way of securing the pin can be used.
[0059] In yet another embodiment, the shell bearing portions are eliminated altogether. In some alternatives, either the journal or the bearing cap inner cylindrical surface is provided with a surface coating that is suitable to serve as a bearing material. Optionally, oil grooves are included to allow passage of the oil to bearing surfaces.
[0060] FIGS. 8A and 8B illustrate bearing shell portions that are fixed together. This ensures that the lubrication passes through the lubrication grooves, as described below. If the pullrod is always under tension, then there is no need to secure the bearing shell portions to each other as the forces in the system cause the bearing shell portions to remain pressed against the journal. Thus, in one embodiment, there are no screws or pins holding the two together. In assembly, the bearing shell portions can be held onto the journal by a thicker oil or grease until secured in place when the bearing caps and connecting rods are installed. Even in a system with momentary instances of a loss of the pressure, it may be possible to withstand such short durations with a momentary loss of oil flow thereby also allowing the bearing shell portions to be installed without screws or pins.
[0061] In an alternative embodiment roller bearing portions 280 are used instead of bearing shell portions. Roller bearing portions 280 include a cage 284 into which needle bearings 282 are retained.
[0062] In FIG. 10 , a cross section of one of the pinned joints between connecting rod 160 a and bearing cap 184 a is shown. Pin 204 is inserted through aligned orifices in finger 196 a , and tabs 164 a and 166 a . One of snap rings 206 can be installed before or after insertion of pin 204 . At least one of snap rings 206 is installed in one of the annular grooves formed the orifices in one of tabs 164 a and 166 a . A similar configuration may be used to couple the connecting rod 160 a and bearing cap 184 a involving fingers 186 a and 188 a with tab 180 a.
[0063] FIG. 11 illustrates a couple of alternative embodiments. At the bottom of the joint as shown in FIG. 11 , a pin 238 sits proud of the aligned orifices in bearing cap 184 a and connecting rod 244 . A snap ring 237 engages with a groove on pin 238 . In configurations with sufficient space, such a configuration may be desirable to avoid providing a groove within the orifice through which the pin sits, such as is shown in FIG. 10 to accommodate the snap rings within the orifice. In FIG. 11 , a counter bore 242 and a groove 240 are shown, but not needed for the pin 238 to snap ring 237 connection as shown. Such counter bore 242 and groove 240 are shown to illustrate the modifications to the orifice that accommodate the upper connection scheme. In the upper example, pin 238 has a head 239 with a larger diameter than the pin body and sits on the shoulder formed by the counter bore 242 . A snap ring 245 is inserted proximate head 239 of pin 238 into the groove (not seen individually in FIG. 11 , but is the same as groove 240 shown in the bottom joint.) The upper joint is sufficient to secure pin 238 as head 239 prevents the pin from moving downward and snap ring 245 prevents the pin from moving upward. The lower joint is shown simply for illustration convenience, i.e., to allow discussion of two embodiments relative to one figure.
[0064] A number of pin embodiments are contemplated with a number of tradeoffs. It is desirable have an orifice as small as possible so that the size of the fingers of bearing cap 184 a and the tabs on connecting rod 244 can be smaller. The pin connection at the bottom of FIG. 11 allows this, but at a cost of additional length with the pin extending outwardly from the joint. Another desirable feature is for the parts to be symmetrical with the same machining operation on both ends to avoid potential assembly issues due to orientation.
[0065] A portion of the engine is shown in FIG. 12 at a condition where pistons 12 and 14 in the left hand cylinder (cylinder not shown) are at their position of closest approach and pistons 12 and 14 in the right hand cylinder (cylinder not shown) are their farthest position. A detail of this position is shown in FIG. 13 . At the center is a cross section of a journal 250 that is part of a crankshaft is shown. Oil is provided along the crankshaft through a channel 252 , which is shown in cross section. An oil passage 254 fluidly couples channel 252 through the crankshaft with an outer surface of journal 250 with an opening 255 . As journal 250 rotates, opening 255 provides oil to the inside surfaces of shell bearing portions 200 a and 200 b . Oil passes out through oil holes 227 along grooves 226 through oil holes 260 in bearing caps 184 a and 184 b to provide lubricating between bearing cap 184 a and pullrod 160 b and between bearing cap 184 b and pullrod 160 a which rotate relative to each other a modest amount during the revolution of the crankshaft. It is desirable to maintain oil holes 227 about 30 degrees displaced (one 30 degrees upward and one 30 degrees downward) from a point of maximum force on the bearing cap. To facilitate that and to maintain the oil passages in desirable locations, it is desirable to restrict the motion of the shell bearing portions 200 a and 200 b with their respective bearing caps 184 a and 184 b . In the embodiment shown in FIG. 13 , a pilot hole 256 is provided in the back of shell bearing portions 200 a and 200 b . A hollow pin 258 is inserted through oil passage 260 to index with pilot hole 256 . Pilot hole 256 in bearing cap 184 b is not used. However, for the purpose of keeping bearing shells 200 a and 200 b identical to reduce the number of unique parts in the engine, both bearing shells are provided with pilot holes 256 . Pin 258 is hollow to allow oil to be conducted through pin 258 and passage 260 to the interface between bearing cap 184 a and pullrod 160 b.
[0066] In FIG. 14 , the engine is shown at a different point in the rotation with pistons 12 and 14 of the left hand cylinder at a position of about 60 degrees before top dead center (TDC) and pistons 12 and 14 of the right hand cylinder at a position of about 120 degrees after TDC. As journal 250 is at, or near, its most upward position (upward as shown in FIG. 14 ), pushrod 264 that couples crankshaft 20 to piston 14 of the left cylinder is visible.
[0067] In the detail of the crank connection shown in FIG. 15 , oil passage 254 is displaced and opening 255 is providing oil to a different location on shell bearing portion 200 a than that shown in FIG. 13 . In FIG. 14 , shell bearing portion 200 a is displaced counterclockwise, slightly, compared to the position shown in FIG. 13 . As explained above, shell bearing portion 200 a is pinned to bearing cap 184 a . The slight counterclockwise rotation of bearing cap 184 a and shell bearing portion 200 a is due to pullrod 160 a being cocked upward at the end associated with journal 250 due to journal 250 being at its most upward position, as can be seen in FIG. 14 . As shell bearing portion 200 a is pinned to bearing cap 184 a via pin 258 , they rotate together. Shell bearing portion 200 b , on the other hand, is free floating as can be seen with oil passage 260 rotated clockwise with respect to pilot hole 256 in shell bearing portion 200 b . The range of motion of shell bearing portion 200 b is limited, however, by shell bearing portion 200 a . In fact, shell bearing portion 200 a moves shell bearing portion 200 b.
[0068] An alternative arrangement to restrict the movement of the shell bearing portions is illustrated in FIGS. 16-18 . In FIG. 16 , a detail of the crank connection is shown. The position of the pistons that relates to the position shown in FIG. 16 is identical to that shown in FIG. 12 , i.e., pistons in the left cylinder are at, or near, TDC; and pistons in the right cylinder are at, or near, BDC. Shell bearing portions 200 a and 200 b each have a slot 270 defined in the outside convex surface. Hollow pins 258 are inserted in oil passages 260 and extend inwardly toward shell bearing portions 200 a and 200 b so that they engage with slots 270 . The angle of the circumference of shell bearing portions 200 a and 200 b over which slots 270 extend is related to the relative movement of pullrods 160 a and 160 b as they rotate. (Axes of pullrods 160 a and 160 b are roughly collinear in FIG. 12 ; the axes of pullrods 160 a and 160 b have a relative angle of about 170 degrees in FIG. 14 .) In FIG. 16 , shell bearing portions 200 a and 200 b are displaced counterclockwise compared to their position as shown in FIG. 13 . Their position, in FIG. 16 , is displaced toward one end of travel with respect to slots 270 . The pulling force acting through one of the pullrods 160 a or 160 b is greater than the force on the other pullrod thereby clamping the associated bearing cap against the associated shell bearing portion. The other shell bearing portion without so much clamping force rotates. Of course, movement of the clamped shell bearing portion is restricted by slot 270 . Nevertheless, it is the uneven forces on the shell bearing portions that causes them to end up in a displaced position as in FIG. 15 rather than a neutral position with the interfaces between the shell bearing portions being vertical as shown in FIG. 13 .
[0069] In FIG. 17 , the engine is shown at a position in which the pistons in the left cylinder are at 90 degrees after TDC and the pistons in the right cylinder are at 90 degrees before TDC. A small portion of each of the pushrods 264 is visible in this position.
[0070] In FIG. 18 , a detail of the crank connection related to FIG. 17 is shown. Pin 258 that engages with shell bearing portion 200 a is at one end of slot 270 . However, pin 258 that engages with shell bearing portion 200 b is at an intermediate position between the ends of slot 270 . Shell bearing portions 200 a and 200 b shuttle back and forth, although rotating in concert, depending on the positions of pullrods 160 a and 160 b and the forces acting between shell bearing portions and their associated bearing cap.
[0071] A flowchart indicating a method to assemble the configuration of FIG. 2 is shown in FIG. 19 . In block 400 , bearing shell portions are placed over the crankshaft journal and fastened together. In other embodiments not requiring it, the bearing shell portions are not fastened together, i.e., simply placed over the journal. In block 402 , the bearing shell portions are placed over the bearing caps with the fingers of the bearing caps meshing. In block 404 , flanges of one of the pullrods are aligned with one of the bearing caps with the through holes aligning with the bolt holes. In block 406 , three bolts are inserted through the three through holes and then engaged with the three threaded holes. In block 408 , the other pullrod is aligned with the other bearing cap. In block 410 , the pullrod is bolted to the bearing cap with bolts inserted through the through holes and engaged with the threads in the threaded holes.
[0072] A flowchart indicating a method to assemble the configuration of FIG. 5 is shown in FIG. 20 . In block 420 , bearing shell portions are placed over the crankshaft journal and fastened together. In block 422 , bearing caps are placed over the bearing shell portions with the fingers of the bearing caps meshing. The pin, or pins, of the bearing caps are engaged with the pilot hole or grooves in the bearing shell portions, as appropriate. The orifices of one of the pullrods are aligned with the orifices of one of the bearing caps in block 424 . In block 426 , pins are installed through the aligned orifices. The pins are secured in the aligned orifices. In block 428 , the orifices of the other pullrods are aligned with the orifices of the other bearing caps. In block 430 , pins are installed through the aligned orifices and secured.
[0073] While the best mode has been described in detail with respect to particular embodiments, those familiar with the art will recognize various alternative designs and embodiments within the scope of the following claims. While various embodiments may have been described as providing advantages or being preferred over other embodiments with respect to one or more desired characteristics, as one skilled in the art is aware, one or more characteristics may be compromised to achieve desired system attributes, which depend on the specific application and implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. The embodiments described herein that are characterized as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for particular applications. | Reciprocating motion can be converted to rotary motion through a crankshaft and a connecting rod. In a connecting rod that is primarily in tension, two opposing connecting rods can be coupled to a single journal. Two bearing caps are placed over the journal, the bearing caps having fingers that extend away from the bearing cap with the fingers of the two bearing caps being enmeshed. Fingers of each bearing cap are coupled to the connecting rods. The resulting joint is compact and lighter weight with a shorter journal than prior joints. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional application Ser. No. 62/326,893, filed Apr. 25, 2016, the contents of which are hereby incorporated by reference.
FIELD
[0002] The present invention relates generally to voltage converter systems and specifically to systems adapted to convert low direct-current (DC) input voltages to high DC or AC output voltages.
Background & Summary
[0003] The biggest challenge in designing step-up DC-DC converters relates to the ratio between output voltage and input voltage. The complexity of a DC-DC converter is inversely proportional to Vin/Iin. There is an even bigger problem when power in the range of 2-4 kW and higher with input voltage in the range of 10-12 VDC are required. As depicted in FIG. 15 , when the ratio between input voltage and input current (Vin/Iin) is above 1, the problem will be smaller. i.e. The higher the number, the smaller the problem.
[0004] When the ratio is below 1, the problem increases as the ratio drops. For example, 10 VDC and 1000ADC is problematic. The requirement for DC-DC isolation conversion with power in the range of 20-30 kW for automotive application is not rare. A common requirement is 24 VDC to 400 VDC and 48 VDC to 400 VDC. In this case, engineers typically connect a number of power stages in parallel. This works somewhat, but it has a big disadvantage: there are too many active switches and transformers, which require complex control, higher costs, and reduced reliability.
[0005] One key advantage of the present invention is reduction in complexity of the power transformer. The voltage across the low voltage side of transformer is, on average, twice higher than the input voltage, so the current via the low voltage side of the transformer will have an average value of half of the input current. This results in a reduction in the turns ratio of the transformer and as a result the design and the construction of the transformer will be easier, the efficiency of the transformer will increase, and the cost will be reduced. Additional objects and advantages are achieved because the topology of the present invention does not require a big block capacitor and has a relatively small ripple current on low voltage side—because of input inductors.
[0006] FIG. 1 depicts one embodiment of the present invention. FIGS. 1A & 1B depict a schematic diagram of a simplified/representative view of FIG. 1 , used in some cases for ease of discussion. The regulation of output voltage is accomplished by changing the duty cycle of switches S 1 and S 3 . The switching of S 2 and S 4 is complementary to the switching of S 1 and S 3 (i.e. S 1 & S 4 open when S 2 & S 3 closed, and vice versa).
[0007] The power stage has 3 modes of operation: Duty cycle of 50% wherein “on” time of S 1 and S 3 is half of commutation frequency, duty cycle of less than 50% wherein “on” time is less than half of the commutation frequency, and duty cycle of greater than 50% wherein “on” time is more than half of the commutation frequency. The selection of a mode will be determined by how much gain is required. In other words, the ratio between input and output voltage. Capacitors C 1 and C 2 will charge to an average voltage following this formula.
[0008] In one preferred embodiment, capacitors C 1 and C 2 are big enough so that we can ignore the ripple voltage, inductors L 1 and L 2 are big enough so that we can ignore ripple current, and the resonant frequency of resonant circuit Lr and Cr is equal to the commutation frequency.
[0009] FIGS. 5A-6B show operational characteristics for a 50% duty cycle. Starting at time t 0 , Capacitors C 1 and C 2 are charged with a polarity as shown in FIG. 5B . At time t 0 S 1 is turned-on and current from source V 1 flows via inductor L 1 and S 1 . At the same time (t 0 ) S 4 is turned-on and completes a circuit to discharge C 1 via the resonant circuit Lr and Cr through the load. The current in this circuit starts from zero, will be sinusoidal in waveform, and reaches zero at time t 1 . At the same time S 4 completes a circuit to charge C 2 through inductor L 2 , since S 3 is turned-off this time. The switch S 4 has to be bidirectional because current flows through it in both directions. The current via S 4 starts equal with the current in inductor L 2 and decays because the current from capacitor C 1 is in the opposite direction, and when current in capacitor C 1 reaches maximum the current via switch S 4 will have reversed direction. When the current in C 1 reaches zero (time t 1 ) the current via S 4 will be the same as at time t 0 . At time t 1 S 1 and S 4 are turned-off, S 3 and S 2 are turned-on, and new half cycle (t 1 -t 2 ) starts, similar to period t 0 -t 1 , but the current flowing via resonant circuit will be in the opposite direction to that during the period t 0 -t 1 .
[0010] FIGS. 7A-10B show operational characteristics for an approximately 40% duty cycle. Starting at time t 0 , switch S 4 is ON. The current via S 1 begins with the same value as the current in L 1 , and discharges capacitor C 1 via resonant circuit. The current via S 4 at time t 0 is equal to the current via L 2 and will be reduced by the current from C 1 because it flows in the opposite direction to the current from L 2 . At time t 1 S 1 is turned-off, interrupting the current which will be the summary of the current in L 1 and the current flowing through C 1 and resonant circuit. Also at time t 1 , S 2 turns on and current flows via S 2 matching the current which was interrupted by S 1 . The current via resonant circuit at t 1 starts to decay and at time t 2 it will be zero. Between t 2 and t 3 currents flow via S 2 and S 4 and matching the currents via L 1 and L 2 . At time t 3 , S 3 turns on and S 4 turns off beginning a new conduction period (t 3 -t 4 ), similar to time period t 0 -t 3 .
[0011] FIGS. 11A-14B show operational characteristics for an approximately 60% duty cycle. Starting at time t 0 , S 1 is staying “on” conducting current via inductor L 1 . Also at time t 0 , S 3 turns-off and S 4 turns-on. This commutation completes a circuit to discharge C 1 via resonant circuit. This current is starting from zero and rising sinusoidally. At time t 1 switch S 4 turns-off and S 3 turns-on. This commutation event provides a path for current to flow via resonant circuit to C 2 and S 3 . So, switch S 3 carries the summary of two currents, one from L 2 and another one from resonant circuit, but they are in opposite directions. The current via resonant circuit will linearly decay, and at time t 2 it reaches zero. In time period t 2 -t 3 , current will flow only via S 1 and S 3 , and will be equal to the currents in L 1 and L 2 , respectively. At time t 3 , switch S 1 turns-off and S 2 turns-on and a new period begins (t 3 -t 4 ), similar to period t 0 -t 3 .
[0012] Other configurations may be used with resonant capacitors. In one embodiment, capacitors C 1 and C 2 are the resonant Capacitors, Switches S 1 and S 3 turn-off purely ZVS (Zero Voltage Switched) under full load. When capacitors C 1 and C 2 are of small value, the resonant capacitance will be determined by the combination of capacitors C 1 , C 2 and the capacitor which is connected in series with resonant inductor Lr. In this case, the ripple voltage on capacitors C 1 and C 2 can be high under full load.
[0013] When capacitors C 1 and C 2 are the resonant capacitors, the ripple voltage on C 1 and C 2 can reach 100% under full load conditions and switches S 1 and S 4 will turn-off under purely ZVS. It should be noted that in practical implementation, switches S 1 and S 3 turn-on under ZCS (Zero Current Switched) conditions, because practically there will always be a small inductor which is connected in series with capacitors C 1 and C 2 . All this helps to significantly reduce switching losses. This topology has many varieties of behavior which depend on value of capacitors C 1 and C 2 . It should also be noted that RMS current via these capacitors is almost equal to RMS current via the primary transformer winding. The foregoing considerations necessitate that attention should be paid to the selection of value and type of these capacitors.
[0014] FIGS. 17A through 17C depict 50%, 40%, 60% duty cycles, respectively, wherein Ch 1 =gate S 1 , Ch 2 =S 1 , Ch 3 =S 2 , & Ch 4 =current via low voltage side of transformer; 80 A/div. The following table shows the measured results.
[0000]
TABLE
measured results (FIGS. 17A through 17C)
Vin
Vout
Pout W
Eff
10.5
170
1600
0.935
15
170
2100
0.94
22
380
3100
0.945
27
380
3100
0.944
30
380
3100
0.941
52
380
11000
0.94
60
380
10000
0.945
80
380
11000
0.94
[0015] FIG. 2 depicts a DC-AC converter without a DC-link. The following table shows the practical results from this DC-AC converter. In this case the converter can operate as a bidirectional converter and operate as a charger.
[0000]
TABLE
(DC-AC converter of FIG. 2)
Vin
Vout
PoutW
Eff
11
120
1000
0.921
12
120
1200
0.927
14
120
1200
0.931
[0016] In this case, the converter can operate as a bidirectional converter. For step-up DC-DC isolation converters with input voltage below 100 VDC, it is reasonable to use paralleling when the input current is over 600-700 A. The cost of paralleling below this current will be at least twice as high as a single stage under the same conditions (Vin, Pout, efficiency, and commutation frequency).
[0017] The following tables show comparisons of real implementations of these topologies. The cost of the proposed topology is smaller than that of others and it has a wider application area. The proposed topology has better results as far as cost and application area by Vin, but it is limited by capacitors C 1 and C 2 . In other words, more attention should be paid to the selection of these parts. Power transformer characteristics are improved by reduction of turn ratio. Additionally, it is very reasonable to use this topology for DC-AC converter without DC-link, when input ripple current is not desired. The paralleling input power stages have minimum twice higher cost and are not competitive. In other words, the proposed topology is a better solution for higher power at low voltage than parallel input stages.
[0018] The technical aspects and cost characteristics of the proposed topology ( FIG. 1 ) is compared to the topologies depicted in FIGS. 3 & 4 . The comparison of cost per kW was made according to the following norms: Vin, Vout, Pout and efficiency are the same for each topology. The following table shows a comparison of the proposed topology of the present invention (“Prop”) vs N 1 ( FIG. 3 ), N 2 ( FIG. 4 ), & DAB (Double Active Bridge). The latter having received a lot of attention.
[0000]
TABLE
Cost
Max
Vin
Vout
Comm
Limit by
Sw
Ind
Block C
1 kW
DAB
150 A
10-100
0-1000
50 kHz
Turn-off
8
no
Huge
1.3-1.5
N1
200 A
30-100
0-1000
100 kHz
Turn-off
4
2
no
1.2-1.4
N2
600 A
10-40
Vmax/Vmin = 2
300 kHz
X-form
6
no
1
1.1-1.2
Prop
600 A
10-100
0-1000
200 kHz
C1&C2
4
2
no
1.0
[0019] The following table shows comparisons of implementations of the aforementioned topologies. As can be seen, the cost of the proposed topology is lower than that of others and it has a wider application area. Also, it is very reasonable to use this topology for a DC-AC converter without a DC-link, when low input ripple current is desired. Finally, the proposed topology is a better solution for higher power at low voltage than parallel input stages.
[0000]
TABLE
Pout
Vin
Vout
Comm
Eff
DAB
1.7 kW
10-14
360
20
kHz
92.0
DAB
2.4 kW
30
750
40
kHz
94.5
N1
1.0 kW
20-50
350
50
kHz
95.8
N1
1.4 kW
12
300
20
kHz
92.0
N1
1.6 kW
12
300
20
kHz
88.0
N2
3.5 kW
10.5-16
360
150
kHz
93.5
N2
7.5 kW
20-30
600
120
kHz
94.0
Prop
1.7 kW
10.5-15
170
120
kHz
93.5
Prop
3.1 kW
22-30
380
120
kHz
94.5
Prop
7.0 kW
42-72
380
100
kHz
96.5
[0000]
TABLE
Examples of component values for different resonance configurations
for a sample converter with 12 V input, 360 V output at 2.8 kW:
Primary side
Secondary side
Combined
Component
resonance
resonance
Resonance
C1/C2
10
uF
400
uF
24
uF
C3/C5
10
uF
0.1
uF
0.1
uF
L3
6.5
uH
6
uH
8.5
uH
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Further features of the inventive embodiments will become apparent to those skilled in the art to which the embodiments relate from reading the specification and claims with reference to the accompanying drawings, in which:
[0021] FIG. 1 depicts a schematic diagram of one embodiment of the present invention;
[0022] FIG. 1A depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0023] FIG. 2 depicts a schematic diagram of one embodiment of the present invention;
[0024] FIG. 3 depicts a schematic diagram of a prior art topology (Topology N 1 );
[0025] FIG. 4 depicts a schematic diagram of a prior art topology (Topology N 2 );
[0026] FIG. 6A depicts a waveform diagram for time t 1 to t 2 (50% duty cycle);
[0027] FIG. 6B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0028] FIG. 5A depicts a waveform diagram for time t 0 to t 1 (50% duty cycle);
[0029] FIG. 5B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0030] FIG. 7A depicts a waveform diagram for time t 0 to t 1 (40% duty cycle);
[0031] FIG. 7B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0032] FIG. 8A depicts a waveform diagram for time t 1 to t 2 (40% duty cycle);
[0033] FIG. 8B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0034] FIG. 9A depicts a waveform diagram for time t 2 to t 3 (40% duty cycle);
[0035] FIG. 9B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0036] FIG. 10A depicts a waveform diagram for time t 3 to t 4 (40% duty cycle);
[0037] FIG. 10B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0038] FIG. 11A depicts a waveform diagram for time t 0 to t 1 (60% duty cycle);
[0039] FIG. 11B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0040] FIG. 12A depicts a waveform diagram for time t 1 to t 2 (60% duty cycle);
[0041] FIG. 12B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0042] FIG. 13A depicts a waveform diagram for time t 2 to t 3 (60% duty cycle);
[0043] FIG. 13B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0044] FIG. 14A depicts a waveform diagram for time t 3 to t 4 (60% duty cycle);
[0045] FIG. 14B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0046] FIG. 15 depicts a graph showing the complexity of DC-DC converter is inversely proportional to Vin/Iin;
[0047] FIG. 1B depicts a schematic diagram of a simplified/representative view of FIG. 1 ;
[0048] FIG. 16A depicts a waveform diagram for an alternative embodiment;
[0049] FIG. 16B depicts a schematic diagram of a simplified/representative view of FIG. 16A ;
[0050] FIG. 17A depicts a waveform diagram (50% duty cycle);
[0051] FIG. 17B depicts a waveform diagram (40% duty cycle); and
[0052] FIG. 17C depicts a waveform diagram (60% duty cycle).
DETAILED DESCRIPTION
[0053] FIG. 1 depicts one embodiment of the invention wherein a step-up converter 100 has first and second isolated stages, 101 , 102 , the first isolated stage comprises, a DC power source V 1 ; a first inductor L 1 having a first terminal 103 connected to the DC power source and a second terminal 104 connected to a first terminal 105 of a first capacitor C 1 ; a second terminal 106 of the first capacitor C 1 connected to a first terminal 119 of a primary stage 131 of a transformer Tr; a second inductor L 2 having a first terminal 111 connected to the DC power source V 1 and a second terminal 112 connected to a first terminal 113 of a second capacitor C 2 ; a second terminal 114 of the second capacitor C 2 connected to a second terminal 120 of the primary stage 131 of the transformer Tr; a first switch S 1 having a first terminal 107 connected to the second terminal 104 of the first inductor L 1 and to the first terminal 105 of the first capacitor C 1 , the first switch S 1 having a second terminal 108 connected to ground; a second switch S 2 having a first terminal 109 connected to the second terminal 106 of the first capacitor C 1 and to the first terminal 119 of the primary stage 131 of the transformer Tr, the second switch S 2 having a second terminal 110 connected to ground; a third switch S 3 having a first terminal 115 connected to the second terminal 112 of the second inductor L 2 and to the first terminal 113 of the second capacitor C 2 , the third switch S 3 having a second terminal 116 connected to ground; and a fourth switch S 4 having a first terminal 117 connected to the second terminal 114 of the second capacitor C 2 and to the second terminal 120 of the primary stage 131 of the transformer Tr, the fourth switch S 4 having a second terminal 118 connected to ground. In one embodiment, step-up converter 100 comprises at least one of the first, second, third, or fourth switches, S 1 , S 2 , S 3 , S 4 respectively, being bidirectional. In one embodiment, step-up converter 100 comprises the fourth switch S 4 being bidirectional.
[0054] FIG. 1 depicts one embodiment of the invention wherein the second isolated stage 102 comprises a first diode 133 having a first terminal 122 connected to a first node 135 , and a second terminal 121 connected to a second node 136 ; a second diode 134 having a first terminal 138 connected to the second node 136 , and a second terminal 139 connected to a third node 137 ; a secondary transformer stage 132 having a first terminal 123 connected to the second node 136 , and a second terminal 124 connected to a first terminal 125 of a resonant inductor Lr; a second terminal 126 of the resonant inductor Lr connected to a second terminal 128 of a first resonant capacitor Cr 1 , and to a first terminal 129 of a second resonant capacitor Cr 2 ; a first terminal 127 of the first resonant capacitor Cr 1 connected to the first node 135 ; and a second terminal 130 of the second resonant capacitor Cr 2 connected to the third node 137 ; whereby a load RL can be connected between the first and third nodes 135 , 137 . The second isolated stage 101 of FIG. 1 provides a DC voltage.
[0055] In one embodiment, the second isolated stage 102 comprises, the resonant inductor Lr and first and second resonant capacitors Cr 1 , Cr 2 , having a resonant frequency equal to a commutation frequency. FIG. 2 depicts one embodiment of the invention wherein the second isolated stage 200 comprises, a fifth switch S 5 having a first terminal 204 connected to a first node 205 , and a second terminal 203 connected a first terminal 202 of a sixth switch S 6 ; the second terminal 201 of the sixth switch S 6 connected to a second node 224 ; a seventh switch S 7 having a first terminal 219 connected to the second node 224 , and a second terminal 220 connected to a first terminal 221 of an eighth switch S 8 ; a second terminal 222 of the eighth switch S 8 connected to a third node 218 ; a secondary transformer stage 211 having a first terminal 210 connected to the second node 224 , and a second terminal 212 connected to a first terminal 213 of a resonant inductor 225 ; a second terminal 214 of the resonant inductor 225 connected to a second terminal 207 of a first resonant capacitor Cr 1 ′, and to a first terminal 216 of a second resonant capacitor Cr 2 ′; a first terminal 206 of the first resonant capacitor connected to the first node 205 ; a second terminal 217 of the second resonant capacitor connected to the third node 218 ; and a third capacitor 215 connected between the first and third nodes 205 , 218 ; whereby a load RL can be connected between the first and third nodes 205 , 218 . The second isolated stage 200 of FIG. 2 has an AC output across the load whereas the second isolated stage 101 of FIG. 1 provides a DC voltage.
[0056] While this invention has been shown and described with respect to detailed embodiments thereof, it will be understood by those skilled in the art that changes in form and detail thereof may be made without departing from the scope of the claims of the invention. | An isolated step-up converter having first and second stages is described herein. The second stage can provide either DC or AC output based on the various topologies described. Resonance inductors and capacitors are used and tuned to a commutation frequency in some embodiments. Capacitors and inductors are also used in the first stage. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a process for making a pattern on fabric, such as cloth and clothing, dyed with a colorant or a dye through decolorizing, discoloring, or bleaching. And more particularly, it relates to a process for easily producing an intended pattern on dyed fabric or colored clothing, particularly denim clothing such as Jeans. The invention also relates to an apparatus using in the process. Further, the invention also relates to dyed fabric having a pattern and colored clothing having a pattern that are produced by the process.
[0003] 2. Description of the Related Art
[0004] As one of techniques for improving the fashion value of textile products, such a method has been carried out that a part of dyed cloth or clothing is decolorizing to make a pattern. In particular, because there is a tendency in denim clothing that partially decolorized products have the preference, processing technology for making a pattern has been particularly advanced, and various processes have been proposed. For example, a stone wash method and a sand blast method of applying physical impacts to fabric, and a chemical wash method of chemically decomposing the dye by using a reagent, such as sodium hypochlorite, have been industrially and widely used as general methods.
[0005] While these methods are effective as a process for decolorizing the whole or a wide area of denim clothing, it is very difficult to make an intended pattern of figures and letters on a specified part thereof, and a large-sized equipment is required. A printing method has been used for making an intended pattern. In this method, a pattern mold shaped in a negative image of the intended pattern is plated on dyed fabric, and a paste containing a reagent, such as sodium hypochlorite, is then printed thereon, whereby a dye on the part where the paste is attached is decolorized to make the pattern.
[0006] Other examples of the method for making an intended pattern of figures and letters on denim clothing include a method using a laser (Japanese Patent Laid-Open No. 102386/1998) and a method, in which dyed fabric is further dyed with a mordant dye, and then the mordant dye on an intended part is discharged (Japanese Patent Laid-Open No.13287/1997). What are disclosed with respect to dyed cloth include a method, in which a pattern mold is placed on dyed fabric, and particles are blown thereon (Japanese Patent Laid-Open No. 17381/1994), a method using an ultraviolet ray (Japanese Patent Laid-Open No. 207386/1994), a method using ozone (Japanese Patent No. 2,864,110 or Japanese Patent Laid-open No. 228266/1997) and a method using microorganisms (Japanese Patent Laid-Open No. 97785/1995).
[0007] However, the conventional methods for making an intended pattern of figures and letters have the following problems. In the printing method, which is a decolorizing method by application of a paste, it is necessary that the paste is dried after application and is finally removed. It also requires complicated processing steps, for example, steaming is necessarily carried out on the decolorizing step. Furthermore, since water is used to remove the paste, such a problem arises that a large amount of wastewater containing the paste is formed.
[0008] The foregoing methods for solving the problems of the printing method also have problems. In the methods using a laser or an ultraviolet ray, a large-sized equipment is required for irradiation of light, and there is a possibility that safety of the working environment is jeopardized by irradiation of a laser light beam or an ultraviolet ray. In the method where a mordant dye is discharged, such a step is required that dyed cloth or closing is further dyed with a mordant dye, and thus complicated operation is necessarily added as a method for making a pattern. In the method using particles, fibers of the fabric are liable to be damaged, and there is a possibility of deterioration of the working environment due to flying of powder caused by blowing particles. In the method using ozone, such considerably complicated equipment and operations are required that the processing is necessarily carried out in an airtight vessel due to the use of harmful ozone, and an equipment for removing remaining ozone is necessary. In the method using microorganisms, such considerably complicated operations requiring a long period of time are necessary that the operations are necessarily carried out under temperature conditions, at which the microorganisms are grown, and the operations take several hours.
[0009] Upon considering the diversification of demands of the consumer, such a process is demanded that can easily and quickly make a pattern, but most of the processes having been proposed are those requiring particular processing steps or equipments for decolorizing, and thus no simple process has been practiced.
SUMMARY OF THE INVENTION
[0010] As a result of earnest investigations made by the inventors taking the foregoing problems into consideration, the invention has been completed. An object of the invention is to provide a process for intentionally making a pattern of figures and letters by decolorizing dyed cloth or clothing in a short period of time without forming a large amount of waste water, without causing deterioration of the working environment, and without using any further particular processing step or processing equipment.
[0011] The invention relates to a process for producing a pattern on dyed fabric by decolorization, discoloration or change of color (which is sometimes simply referred to as bleaching). Specifically, the invention relates to a process for making a pattern on dyed fabric containing the steps of: impregnating dyed fabric with a substance forming an oxidized active species upon electrolysis (hereinafter, the substance is sometimes referred to as an electron carrier); inserting the dyed fabric between a pair of electrodes; and applying electricity to the electrodes, whereby only a part of the dyed fabric where electricity is applied is selectively subjected to decolorization, discoloration or change of color.
[0012] In a part where no electricity is applied, no oxidized active species is formed from the electron carrier. Therefore, a pattern of figures and letters can be arbitrarily made by specifying the part where electricity is applied.
[0013] It is possible that at least one of the pair of electrodes is an electrode shaped in a positive image of the pattern. At this time, an anode shaped in a positive image of the pattern is preferably used. In the part other than the electrode shaped in a positive image of the pattern, no oxidized active species is formed, and decolorization, discoloration or change of color does not occur.
[0014] It is also possible upon applying electricity that an electro-nonconductive film or an electro-nonconductive spacer shaped in a negative image of the pattern is inserted between the electrode and the dyed fabric. At this time, the film or the spacer is preferably inserted between an anode and the dyed fabric. In this configuration, even when the electrodes are in a form of a simple plate, the pattern is formed by decolorization, discoloration or change of color caused by following the outer shape and the negative image of the pattern of the electro-nonconductive film or the electro-nonconductive spacer inserted between the electrode and the dyed fabric.
[0015] The invention is also an apparatus with the above-mentioned process for making pattern. Further, this invention relates to dyed fabric having a pattern and colored clothing having a pattern that are produced by the process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] [0016]FIG. 1 is a perspective view showing an embodiment of the process for making a pattern according to the invention.
[0017] [0017]FIG. 2 is a plane view showing an embodiment of a pattern on dyed fabric.
[0018] [0018]FIG. 3 is a plane view showing trousers as colored clothing having a pattern formed thereon.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] The process for making a pattern on dyed cloth or colored clothing as an embodiment of the process for making a pattern on dyed fabric according to the invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the process for making a pattern according to the invention. FIG. 2 is a plane view showing a pattern on dyed fabric. FIG. 3 is a plane view showing trousers as colored clothing having a pattern formed thereon. In FIG. 1, a voltage is applied between an anode 2 and a cathode 3 by a constant current generator 1. Dyed fabric 4 impregnated with an electron carrier and an electro-nonconductive film 5 are inserted between the anode 2 and the cathode 3. The electro-nonconductive film 5 has a cut part 6 shaped in a pattern, and the dye in the cut part is decolorized to form patterns 8 through decolorizing a part of the dyed fabric 4 or clothing 7 as shown in FIGS. 2 and 3.
[0020] The form of the dyed fabric used in the invention is not particularly limited, and any form thereof can be used. For example, fabric in the form of cloth and that in the form of clothing can be used in the process of the invention. Examples of the materials for the cloth and the clothing include natural fibers, such as cotton, wool, silk and linen, semi-synthetic fibers, such as rayon and acetate, and synthetic fibers, such as polyesters, polyamides, polyacrylonitriles and aromatic polyamides. Cloth, sewn products, knitted products and non-woven cloth formed with single fibers or mixed fibers of the materials are also included. Examples of the dye for dyeing the fabric include direct dyes, acidic dyes, basic dyes, mordant dyes, acidic mordant dyes, metal-containing complex dyes, sulfide dyes, naphthol dyes, disperse dyes, reactive dyes, cationic dyes, vat dyes and fluorescent dyes. Various kinds of colorants may also be used as the dye.
[0021] When dyed cloth or clothing impregnated with the electron carrier is inserted between the electrodes, to which electricity is applied, an oxidized active species is formed from the anode. decolorizing is carried out by using the oxidized active species. As the oxidized active species used herein, hypochlorous acid formed through electrolysis of sodium chloride can be applied, but any electron carrier can be used irrespective to organic substances and inorganic substances as far as it forms from the anode through electrolysis not only hypochlorous acid but any oxidized active species capable of decomposing the dye. Examples thereof include halogen-containing salts containing halide ion, such as chloride ion, bromide ion and iodide ion, or containing hypochlorite ion; transition metal salts containing metallic ion, such as cerium ion and manganese ion; and organic compounds, such as tertiary amines, sulfides and phenothiazines. In those of examples, halogen-containing salts are preferable. Further, the material containing halide ion, especially chloride ion, is more preferable. Furthermore, sodium chloride is most preferable. Sodium bromide and sodium hypochlorite are also used preferably.
[0022] Any material that transmits electricity and forms a stable electrode can be basically used as the electrode material. While the electrode material is necessarily selected depending on the kind of the electron carrier, those electrodes that have been considered in the industrial electrolytic process of sodium chloride can be used in the case where sodium chloride is used as the electron carrier. Usable examples of the anode include platinum, carbon, titanium, titanium carrying ruthenium oxide, an anti-corrosion alloy, and an electroconductive metallic oxide, such as tin oxide. Usable examples of the cathode include platinum, carbon, iron, stainless steel, nickel, and an electroconductive metallic oxide, such as tin oxide.
[0023] The concentration of the solution containing the electron carrier may be any range as far as electricity can be turned on. When the concentration is too small, the resistance between the both of electrodes is increased to cause a problem in that generation of the oxide active species becomes unstable. When the concentration is too large, the oxidized active species is generated as concentrated at a part of the electrode to cause a problem that uniform decolorizing cannot be achieved. Therefore, in the case where sodium chloride is used as the electron carrier, the concentration may be from 0.1 g/L to the saturated concentration, and a preferred range of the concentration where no decolorizing unevenness occurs is from 0.1 to 10 g/L.
[0024] The amount of the solution containing the electron carrier may be such an amount that the cloth is impregnated. When the amount of the solution is too small, the resistance between both of the electrodes is increased to cause a problem in that generation of the oxide active species becomes unstable. Therefore, the amount of the solution is preferably from 100% to the saturated water content. In the case where the solution is vaporized during the process, water or solution containing the electron carrier is supplied.
[0025] The amount of electrification may be about several mA/cm 2 , and when the area of electrification is about 25 cm 2 , constant current generator of several hundreds mA can be used. The processing time can be adjusted by the amount of electrification, and when 100 mA is applied to an area of about 25 cm 2 , the processing time may be about from 1 to 10 minutes. The degree of decolorizing can be arbitrarily achieved by controlling the amount of electrification and the processing time.
[0026] The pattern can be made with an anode shaped in a positive image of the pattern, such as an anode shaped in a pattern and an anode with a pattern stamped by cutting a part of the anode. According to the configuration, such a pattern can be obtained that is formed by decolorizing in the shape of the anode. In the case where the anode is in a form of a simple plate, the pattern can be similarly made by using an electro-nonconductive frame, such as a film and a spacer, shaped in a negative image of the pattern inserted between the cloth or clothing and the anode. According to the configuration, such a pattern can be obtained that decolorizing does not occur in the shape of the frame.
[0027] The frame is preferably formed with an electro-nonconductive material solely or in combination of plural kinds thereof. Examples thereof include plastics, rubber, glass and ceramics. An electroconductive material, such as metals, can also be used as the frame after coating the surface thereof with the electro-nonconductive material.
[0028] Protons are consumed on the cathode, to become surroundings of the cathode alkaline. When unfavorable influences occur thereby, the pH can be controlled by inserting an ion exchange film between the fabric and the cathode.
[0029] A sharp pattern can be formed by making the electrodes and the fabric in close contact with each other. A pattern with a blurry contour can also be formed by loosing the contact between the fabric and the anode or by inserting a porous spacer impregnated with the electron carrier between the fabric and the anode. The electro-nonconductive frame may not be in one united body, and for example, a frosting pattern can be made by inserting sand.
[0030] According to the process of the invention, because a pattern can be easily and simply made by decolorizing, an arbitrary pattern can be made by the consumers after purchase of the product, and a pattern can be made at retail stores as services. The apparatus using in the process of the invention comprises at least a pair of electrodes. The consumers can also make a pattern by themselves by using a kit as the apparatus utilizing the invention. Containing a electric source, such as a constant current generator, to the kit is also utilized in addition to the electrodes mentioned above. Moreover, the electrodes being shaped in a pattern is also desirable. Further, in addition to the electrodes, it is also preferable that a kit is comprising an electro-nonconductive film or an electro-nonconductive spacer shaped in the pattern. It makes for the consumers to be able to produce easily a desirable shape in the pattern by themselves. As shown in above description, it is considered that the process of the invention exerts high industrial value that patterns that supports the needs of the consumers are immediately provided.
[0031] The invention will be further described in detail with reference to the following examples and comparative examples. In the examples and comparative examples, the amount of decolorizing was measured and evaluated in the following manner. A sample having been sufficiently washed with water after applying electricity was measured for reflectance by a color measurement system (AUCOLOR-NF, produced by Kurabo Industries, Ltd.), and it was converted to a Kubelka-Munk function over the entire wavelength (interval: 20 nm), so as to evaluate the total K/S.
EXAMPLE 1
[0032] Denim cloth dyed with indigo (cotton twill fabric, warp thread density: 65 per inch, apparent yarn number: 7; weft thread density: 44 per inch, apparent yarn number: 8; total K/S: 431.78) impregnated with a sodium chloride solution of 10 g/L and a plastic film formed with polyester (thickness: 0.1 mm) were inserted between electrodes (fluorine-coated tin oxide thin film electrodes, resistance: 15 Ω, dimension: 5×5 cm) The plastic film was placed on a lower half of the area, on which electricity was to be applied, between the anode and the cloth. Electricity was applied with an electric current of 100 mA for 7 minutes, and as a result, a part of the cloth having no film placed thereon was selectively decolorized. After application of electricity, the cloth was washed with water to remove remaining oxidized active species and then sufficiently dried. The resulting denim cloth was measured for the total K/S. The results obtained are shown in the lowermost lines of Tables 1 and 2 below.
EXAMPLE 2
[0033] The same procedures as in Example 1 with the same conditions for the electrification were carried out except that the processing time was changed to 3 and 5 minutes, and the total K/S was measured. The results obtained are shown in Table 1. The degree of decolorizing is increased corresponding to the processing time, and thus the extent of decolorizing can be easily adjusted by the electrification time.
TABLE 1 Degree of Total K/s decolorizing (%) Without 431.78 electrification 100 mA, 59.87 86.1 3 min.processed 100 mA, 39.59 90.8 5 min.processed 100 mA, 24.69 94.3 7 min.processed
EXAMPLE 3
[0034] The same procedures as in Example 1 with the same conditions for the electrification were carried out except that the electric current was changed to 40 and 60 mA, and the total K/S was measured. The results obtained are shown in Table 2. The degree of decolorizing is increased corresponding to the electric current, and thus the extent of decolorizing can be easily adjusted by the electric current.
TABLE 2 Degree of Total K/S decolorizing (%) Without 431.78 electrification 40 mA, 84.24 80.5 7 min.processecd 60 mA, 35.56 91.8 7 min.processecd 100 mA, 24.69 94.3 7 min.processed
Comparative Example
[0035] The same procedures as in Example 1 with the same conditions for the electrification were carried out except that ion exchanged water and a sodium sulfate solution of 10 g/L were used as the solution, with which the cloth was impregnated. The results obtained are shown in Table 3. Substantially no decolorizing occurred in the cases of ion exchanged water and a sodium sulfate solution.
TABLE 3 Degree of Total K/S decolorizing (%) Without 431.78 electrification Ion exchanged water 426.12 1.3 Sodium sulfate 430.15 0.4 solution
EXAMPLE 4
[0036] The same procedures for electrification as in Example 1 were carried out except that a circular graphite electrode (obtained by press-molding flaky graphite at 30 Mpa, diameter: 20 mm) was used as the anode. After electrification for 7 minutes, denim cloth having a decolorized pattern of a circular shape (total K/S: 43.10, degree of decolorizing: 90.0%) was obtained.
EXAMPLE 5
[0037] The same procedures for electrification as in Example 1 were carried out except that a sodium bromide solution of 18 g/L was used as the solution, with which the cloth was impregnated. After electrification for 7 minutes, denim cloth that was decolorized only in the part, where electricity was applied, (total K/S: 63.21, degree of decolorizing: 85.4%) was obtained.
EXAMPLE 6
[0038] The same procedures for electrification as in Example 1 were carried out except that a sodium hypochlorite solution of an effective chlorine concentration of 1% (guaranteed reagent, produced by Kishida Chemical Co., Ltd.) was used as the solution, with which the cloth was impregnated. After electrification for 7 minutes, denim cloth that was considerably decolorized only in the part, where electricity was applied, was obtained. The part, where electricity was not applied, had a total K/S of 425.34 and a degree of decolorizing of 1.5%, and the part, where electricity was applied, had a total K/S of 54.9 and a degree of decolorizing of 87.3%.
EXAMPLE 7
[0039] The same procedures for electrification as in Example 1 were carried out except that electricity was applied to an area of 5×6 cm, and a sample for measuring tensile strength having a size of 5×30 cm, in which the decolorized area of 5×6 cm was included, was obtained. The tensile strength of the sample was measured according to JIS L1096 8.12. As shown in Table 4, reduction in strength was not observed even though the degree of decolorizing was increased.
TABLE 4 Degree of decolorizing (%) Tensile strength (N) 0 1238 86.6 1237 91.2 1212
EXAMPLE 8
[0040] Some pieces of multifiber union cloth (according to JIS L0803) dyed with various kinds of dyes were impregnated with a sodium chloride solution of 10 g/L and were inserted between electrodes (fluorine-coated tin oxide thin film electrodes, resistance: 15 Ω, dimension: 5×12 cm). A plastic film formed with polyester (thickness: 0.1 mm, dimension: 2.5×12 cm) was inserted between the anode and the cloth, and electricity was applied with an electric current of 100 mA for 7 minutes. As a result, a part of the cloth having no film placed thereon was selectively decolorized. After application of electricity, the cloth was washed with water to remove remaining oxidized active species and then sufficiently dried. The resulting cloth was measured for the total K/S. The results obtained are shown in Table 5.
TABLE 5 Total K/S Without Electrification Degree of Dye Original yarn electrification processed decolorizing (%) C. I. Direct Red 28 Cotton yarn 221.66 86.93 60.8 (Congo Red) Nylon filament yarn 93.36 88.85 53.6 Worsted yarn 191.61 120.39 37.2 Rayon filament yarn 172.88 114.32 33.9 Raw silk 145.50 74.26 49.0 C. I. Direct Blue Cotton yarn 240.97 63.09 73.8 200 Nylon filament yarn 39.65 9.82 75.2 Worsted yarn 50.00 30.30 39.4 Rayon filament yarn 215.85 74.93 65.3 Raw silk 163.22 59.02 63.8 C. I. Acid Red 94 Nylon filament yarn 25.68 16.97 33.9 (Rose Bengal) Rayon filament yarn 108.67 88.39 18.7 Raw silk 48.62 25.27 48.0 C. I. Disperse Nylon filament yarn 454.73 325.72 28.3 Orange Acetate filament yarn 657.06 247.33 62.4 Worsted yarn 301.45 213.68 29.1 Acrylic spun yarn 502.73 442.07 12.1 Raw silk 428.46 115.03 73.2 Polyester spun yarn 433.88 424.94 2.1
[0041] According to the process for making a pattern of the invention, a product of dyed cloth or colored clothing, particularly a denim product, formed with a pattern of figures and letters by decolorizing can be provided, and a fine and complicated pattern can be made by the process with small blur at color contours. A product having a degree of decolorizing that is arbitrary adjusted can be easily provided by adjusting the processing time and the electric current. Furthermore, because no particular equipment or processing step is required, other various advantageous effects are also exerted, for example, patterns that support the needs of the consumers can be immediately provided. | A process for making a pattern according to intended design on cloth or clothing, particularly denim clothing, dyed with a colorant or a dye through decolorizing is provided. Fabric or clothing dyed with a colorant or a dye is impregnated with a substance forming an oxidized active species upon electrolysis and inserted between a pair of electrodes, and electricity is applied to the electrodes, whereby only a part where electricity is applied is selectively decolorized to make a pattern with gradated effect. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the production of smooth surfaced pressboard from polyaramid fibers.
2. Prior Art
U.S. 4,752,355 discloses a polyaramid pressboard and its production. The "Standard Pressboard" precursor referred to in this reference, though having relatively low density, has a very rough surface. The compression resistant pressboard product prepared by this reference is very dense.
SUMMARY OF THE INVENTION
The present invention relates to forming pressboard from polyaramid fiber by pressing to a predetermined controlled thickness. Surprisingly, because of the predetermined amount of compression a relatively smooth pressboard is obtained with relatively low density.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to polyaramid pressboard intended for use as a thin thermal barrier in automobiles. Present low density polyaramid pressboards have a rough surface caused by the screen pattern from the press used in their manufacture. This rough surface is undesirable when the pressboards are used in automobiles because such a surface can lead to increased pickup of dirt, dust, grease and moisture. Thus, it is desirable to have a smooth, impervious surface to prevent this pickup.
The present invention uses a platen operated at above the glass transition temperature (Tg) of the polyaramid being used to form the pressboard similar to the technique used to form dense polyaramid pressboards; but uses a stop mechanism so that a pressboard having a relatively low density of 0.70 to 0.95 g/cc is produced. The high temperature of the platen serves to fuse the polyaramid fibers near the surface of the pressboard making it impervious to contaminants while still forming a pressboard of low enough density to be useful as a thermal barrier and be economically attractive for this use.
The pressboard of the present invention comprises 20 to 95% by weight polyaramid fibrids and 80 to 5% by weight high temperature resistant floc, said pressboard having a calculated void volume of 31 to 49% by volume of the pressboard, and a thickness of 0.8 to 5.0 mm.
Preferably the pressboard comprises 50 to 70% by weight polyaramid fibrids and 30 to 50% by weight high temperature resistant floc. Preferably the high temperature resistant floc consists of a polyaramid. Preferably the polyaramid fibrids and high temperature resistant floc consist essentially of poly(p-phenylene isophthalamide)(MPD-I). The pressboard preferably comprises polyaramid fibrids and floc and has a thickness of 0.8 to 5.0 mm, a density of 0.70 to 0.95 g/cc and most preferably 0.70 to 0.80 g/cc.
The pressboard is prepared using an aqueous slurry of 0.1 to 2.0% by weight total solids comprising 20 to 95% by weight polyaramid fibrids and 80 to 5% by weight high temperature resistant floc having a length of 2 to 12 mm, said polyaramid fibrids and high temperature floc having a melting point of higher than 320° C. The slurry is formed into a waterleaf having a water content of 50 to 95% by weight. The waterleaf is combined into multiple layers to form a wet lap, the wet lap is pressed at 100° C. to 200° C. under a pressure of 10 to 60 kg/cm 2 to form low density pressboard having a calculated void volume of 30 to 60% by volume of the pressboard. The low density pressboard is dried, ultimately at 270° C. to 320° C., until no further moisture is evolved, and finally pressed at 8 to 350 kg/cm 2 at 270° C. to 320° C. with a mechanical stop to prevent excessive densification. Preferably the pressing temperature is 275°-300° C. Most preferably, the final pressing is at 275° to 285° C. and the pressure is 15 to 70 kg/cm 2 . Preferably the pressboard is cooled under restraint to prevent warping.
By "polyaramid" is meant a thermoplastic polymer containing repeating units of the formula
-(-NH--Ar--NH--CO--Ar'--CO-)-
wherein Ar and Ar' aromatic groups containing 6 to 14 carbon atoms. Preferably -Ar- and -Ar'- are phenylene, biphenylene, or naphthalene groups. Especially preferred is the case where both -Ar- and -Ar'- are phenylene groups.
By "polyaramid fibrids" is meant small, nongranular, nonrigid fibrous or film-like particles of a polyaramid having a melting point higher than 320° C. Two of their three dimensions are of the order of microns. Their smallness and suppleness allows them to be deposited in physically entwined configurations such as are commonly found in papers made from wood pulp. Fibrids can be prepared by precipitating a solution of the polyaramid into a coagulant such as described in U.S. Patent No. 3,018,091.
By "high temperature resistant floc" is meant short fibers, typically having a length of 2 to 12 mm and a linear density of 1-10 decitex, made of a material having a melting point higher than 320° C. such as polyaramids, aromatic polyamide-imides, aromatic polyimides, polybenzimidazoles, polybenzoxides, and the like, or inorganic materials such as glass, ceramic materials, aluminum, and the like. Other high temperature materials such as mica may also be present in relatively fine subdivided form.
By "polyaramid floc" is meant short fibers cut from fibers by a process such as those described in U.S. Pat. Nos. 3,063,966; 3,133,138; 3,767,756; and 3,869,430.
The polyaramid pressboard may be prepared by feeding an aqueous slurry of polyaramid fibrids and polyaramid floc to a cylinder paper making machine whereby water is removed and multiple layers of fibrous material having a water content of 50 to 95% by weight of the wet sheet are built up to a wet lap of the desired thickness. The wet lap is cut from the cylinder, laid flat and pressed at 100° to 200° C. under a pressure of 10 to 60 kg/cm 2 . The resulting pressboard has a calculated void volume of 35 to 50% by volume of the pressboard.
In accordance with the present invention, the pressboard prepared, as described above, is further dried, ultimately at a temperature of 270° to 320° C., until substantially no further moisture is evolved; and it is then pressed at a temperature of 270° to 320° C. and a pressure of 8 to 350 kg/cm 2 wherein the pressure applying means is limited mechanically in the amount of compression that can be applied to the pressboard, preferably followed by cooling the pressboard under restraint. A pressboard having the desired properties of a density of 0.70 to 0.95 g/cc, a calculated void volume of 31 to 41% by volume of the pressboard, and a surface smoothness of less than 300 micro inches (7.33×10 -6 m) can be obtained in both the machine and cross directions. Machine direction (MD) and cross direction (CD) of the pressboard is based on the original sheet orientation to the paper machine.
The drying is preferably accomplished by step-wise increases in temperature. Moisture evolution is facilitated by application and release of light pressure. In general the pressing is preferably at 275° to 300° C. at 15 to 70 kg/cm 2 for at least 5 minutes, but thick products may require longer times. The final temperature, in the drying steps, should be at or above the glass transition temperature (Tg) of the polyaramid fibrids which, in the case of the preferred poly(m-phenylene isophthalamide), is about 275° C.
The pressboard of this invention is useful in forming insulation such as for use in automobiles in particularly for the firewall separating the engine compartment from the passenger compartment. Products of this invention have a calculated void volume of 31 to 41% by volume of the pressboard and preferably a calculated void volume of 42 to 49% by volume and a preferred range of surface smoothness of less than 300 micro inches (7.33×10 -6 m).
TESTS
Density: Dry pressboard is cut into a rectangular sample measuring at least 10 cm by 10 cm making sure that the corners are cut square so that the upper and lower faces of the sample are of the same area and that the dimensions can be measured accurately. The length and width of the sample are measured to an accuracy of at least 0.25 cm. The thickness of the sample of pressboard is measured in at least ten places substantially equally apart around all sides of the pressboard, away from the edges, using a micrometer caliper which contacts the sample with surfaces having a diameter of about 0.16 cm at a pressure of about 0.1 kg/cm 2 , to an accuracy of at least 0 00025 cm, averaging the ten thickness measurements. The sample of the pressboard is then weighed to the nearest 0.0001 g. The volume of the pressboard V b is calculated in cm 3 and the weight is divided by the volume to give the density in g/cm 3 .
Calculated Void Volume: The void volume in cm 3 , V v , of a sample of the pressboard is determined from the relationship
V.sub.b =V.sub.m +V.sub.v or
V.sub.v =V.sub.b -V.sub.m where
V b is the volume of the pressboard in cm 3 as determined above, V m is the total volume of all materials comprising the pressboard, and V v is the remaining volume in cm 3 , which is taken as the void volume. V m is determined from the weights and densities of each of the materials of which the pressboard is made, calculated as follows: ##EQU1## where W f is the weight in g of the polyaramid fibrids in the pressboard sample, W i is the weight in g of the floc (including any other non-fibrid high temperature resistant material) in the pressboard sample, and Pi is the density of the material of which the floc is made (1.38 g/cm 3 for MpD-I and 1.44 g/cm 3 for poly(p-phenylene terephthalamide)). When there is more than one kind of floc (or other high temperature resistant material such as mica), Wi/Pi is calculated as follows: ##EQU2## where i=1, 2, . . . , n. The calculated void volume, as a percentage volume, % V v is then calculated as follows: ##EQU3##
In the case of a 100% MPD-I pressboard sample having a weight, in grams, of W b and a volume, in cm 3 , of V b , and since for this case ##EQU4##
The calculated void volume is a measure of all of the voids, both isolated voids and interconnected voids, in a sample of pressboard.
PREFERRED EMBODIMENTS OF THE INVENTION
EXAMPLE 1
A. Preparation of "Standard Pressboard"
Filaments of poly(m-phenylene isophthalamide)(MPD-I) having an inherent viscosity of 1.5, as measured from a 0.5 wt % solution in concentrated sulfuric acid, were dry spun from a solution containing 19 wt % MPD-I, 70 wt % dimethylacetamide (DMAc), 9 wt % calcium chloride and 2 wt % water. On leaving the drying tower, the as-spun filaments were given a preliminary wash with water so that they contained about 60 wt % DMAc, 15 wt % calcium chloride and 100-150 wt % water, based on the weight of dry polymer. The filaments were washed and drawn 4× at 90° C. in a counter-current extraction-draw process in which the calcium chloride, determined as chloride content and DMAc content were reduced to about 0.1 wt % and 0.5 wt % respectively. The filaments were crystallized immediately after drawing by passing them over hot rolls at a temperature of about 340° C. The filaments so-produced had a linear density of 2.2 decitex (2.0 denier), a tenacity of about 3.7 dN/tex (4.2 g/denier), an initial modulus of 70 dN/tex (79 gpd) and an elongation of 34%. The filaments were cut to floc having a length of 3.4 mm (0.135 in).
Fibrids of MPD-I having an inherent viscosity of 1.5 as determined from a 0.5 wt % solution in concentrated sulfuric acid, were prepared substantially as described by Gross in U.S. Pat. No. 3,756,908, column 5, lines 34-54, stopping short of the refining step.
An aqueous slurry was prepared containing 1.0 wt % fibrids and floc having a solid composition containing 60 wt % of the above MPD-I fibrids and 40 wt % of the MPD-I floc. The slurry was held in an agitated vessel and then pumped to a double disc refiner (Beloit Jones Model 3000 20-inch Double Disc refiner, made by the Jones division of the Beloit Corporation, Dalton, Mass. 01226) equipped with refining discs containing narrow bass and channels with surface dams. The plates of the refiner were positioned with a gap of 0.5 mm (20 mils) between the rotor and stator plates. The rotor plates were operated at 900 rpm. After passing through the refiner, the slurry was passed through a second refiner operating under the same conditions. After the two passes through the refiners the fibrids in the slurry were well reduced in size and well opened into fibrid films, while the floc fibers were well distributed among the fibrids. The slurry made in this way was then diluted to approximately 0.1 wt % solids and fed to a conventional cylinder wet paper-making machine upon which a continuous sheet of wet paper was made and transferred to an endless felt, the moisture content being adjusted by suction and pressure to about 400% based on solids (80% by weight based on wet sheet). The weight of the solids in the wet paper was approximately 36 g/m 2 . The continuous wet sheet was next delivered to a forming roll, where it was wound continuously on a cylindrical tube until it overlapped about 70 times. A longitudinal cut was then made in the layered paper and the entire thickness of wet lap (wet layered paper) was removed and placed between platens of a hot press; -- the platens being maintained at 140° C. and having been covered with a wire screen to facilitate moisture removal. The press was loaded at contact pressure, and the pressure was raised to and maintained for one hour at 35 kg/cm 2 while the temperature was maintained at 140° C. The product, herein designated as "Standard Pressboard" was a low density polyaramid pressboard approximately 1.6 mm thick. It was found to have a density of 0.85 g/cm 3 , a basis weight of 37 ounces per square yard (1.2 kg/m 2 ), a calculated void volume, and a % V v of 38% by volume pressboard.
B. One 25.5 cm×25.5 cm rectangular sheet of "Standard Pressboard" prepared as described in Part A above was predried at 150° C. The pressboard was then placed immediately in a hot press having platens oil heated to 280° C. and subjected to three 1 minutes cycles of contact pressure at 2 kg/cm 2 and 280° C. followed by release of pressure. A one-minute cycle wherein the platens were heated to 280° C. and the space between the platens was mechanically set at 1.4 mm followed. The pressboard was taken out hot and placed under contact pressure in a separate press, initially at room temperature and water cooled to absorb the heat of the pressboard. The product was a polyaramid pressboard approximately 1.4 mm thick. It was fond to have the density and smoothness reported in the Table below.
EXAMPLE 2
Example 1 was repeated except the "Standard Pressboard" Basis Weight was 36 ounces per square yard (1.22 kg/m 2 ) and the final press cycle was shortened to 30 secs. It was found to have the density and smoothness reported in the Table below.
EXAMPLE 3
Example 1 was repeated except the "Standard Pressboard" Basis Weight was 30.6 ounces per square yard (1.04 kg/m2). It was found to have the density and smoothness reported in the Table below.
EXAMPLE 4
Example 1 was repeated except the "Standard Pressboard" Basis Weight was 36.6 ounces per square yard (1.24 kg/m 2 ). It was found to have the density and smoothness reported in the Table below.
EXAMPLE 5
Example 1 was repeated except the "Standard Pressboard" Basis Weight was 36 ounces per square yard (1.22 kg/m 2 ). It was found to have the density and smoothness reported in the Table below.
EXAMPLE 6
Example 1 was repeated except the "Standard Pressboard" Basis Weight was 37.6 ounces per square yard (1.27 kg/m 2 ). It was found to have the density and smoothness reported in the Table below.
TABLE______________________________________ MD Range CD Range Density Micro- Micro-Example g/cc inches (×10.sup.7 m) inches (×10.sup.7 m)______________________________________1 0.85 150-190 (38-48) 130-188 (33-46)2 0.73 200-240 (51-61) 170-240 (43-61)3 0.79 150-210 (38-53) 200-250 (51-60)4 0.90 90-140 (23-36) 130-170 (33-43)5 0.88 120-180 (30-46) 100-130 (25-33)6 0.91 140-170 (36-43) 130-170 (33-43)______________________________________ | High temperature resistant pressboard having a density of 0.70 to 0.90 g/cc, a calculated void volume of 31 to 49, percent by volume of said pressboard and a smoothness of 80 to 250 microinches MD range and 90 to 260 microinches is disclosed. The pressboard is prepared by wet laying an aqueous dispersion of polyaramid fibrids and floc to form a waterleaf building up layers to form a wet lap which is dried and then pressed at 270° C. to 520° C. rising a press with a predetermined minimum opening to form the desired smooth low density pressboard. | 3 |
RELATED APPLICATION
This patent application is a continuation of application Ser. No. 09/102,299, filed Jun. 22, 1998, now U.S. Pat. No. 6,020,482, which is a divisional of application Ser. No. 08/343,433, filed Nov. 23, 1994, now abandoned. This patent application also claims priority to French Application 93-04117, filed Apr. 7, 1993, and French Application 92-06383, filed May 25, 1992.
FIELD OF THE INVENTION
The present invention relates to the bioreversible functionalization of phosphate or phosphonate groups of biologically active compounds.
The present invention relates more particularly to phosphotriester-type biologically active compounds bearing phosphate or phosphonate groups which are protected by protecting groups that are bioreversible in an intracellular medium.
BACKGROUND OF THE INVENTION
Compounds bearing a phosphate or phosphonate group have a negatively charged ionic nature and a physiological pH. As a result, the therapeutic activity of such compounds is limited by the low diffusion of negatively charged compounds across biological lipid membranes. Moreover, compounds bearing phosphate groups are readily dephosphorylated by the action of phosphatase enzymes in the blood or on cell membranes, which enzymes dephosphorylate substrate compounds. In general, charged phosphate or phosphonate compounds are poorly absorbed via oral administration, and do not diffuse efficiently across cell membranes or even the cerebral barrier, which are lipidic in nature.
Certain compounds, such as nucleoside derivatives or analogs, are active agents that are administered in non-phosphorylated form, but are phosphorylated in vivo in the form of metabolic monophosphate or triphosphate to become active.
Thus, nucleoside derivatives having antitumor activity, such as 5-fluorouridine, 5-fluoro-2′-deoxyuridine or 1-O-D-arabinofuranosylcytosine, exert their activity in phosphorylated form.
Similarly, in order to exert their antiproliferative activity, certain nucleoside or phosphononucleoside analogs need to be phosphorylated into the corresponding triphosphate thereof by cellular or viral enzymes; this triphosphate is then capable of inhibiting the viral and/or cellular polymerases.
Among the various structural classes of antiviral agents, 2′,3′-dideoxynucleosides are among the most effective compounds in the treatment of AIDS. However, these nucleoside analogs must undergo a biotransformation by cell kinases in order to exert their activity on the replication of HIV, the etiological agent of AIDS. This metabolization occurs via the dideoxynucleoside 5′-monophosphate and then the 5′-diphosphate to lead to the 5′-triphosphate, which is an inhibitor of HIV reverse transcriptase and which thereby interferes with the biosynthesis of viral DNA.
Despite their great therapeutic potential, 2′,3′-dideoxynucleosides suffer from limitations, in particular the low metabolizability of some of them by kinases into triphosphate. 2′,3′-Dideoxyuridine 5′-triphosphate, for example, is an excellent inhibitor of reverse transcriptase (Z. Hao et al., Proc. Am., Assoc. Cancer Res., 1988, 29, 348, E.Matthes et al., Biochem. Biophys. Res. Commun, 1987, 148, 78-85). However, the nucleoside thereof is able to inhibit the replication of HIV in vitro. Studies have shown that this result is linked to the low metabolizability of the nucleoside into its monophosphate by cell kinases (Z. Hao et al. Mol. pharmacol. 1990, 37, 157-153).
Thus, AZT is successively metabolized into the triphosphate thereof (AZTP), which is a potent inhibitor of HIV reverse transcriptase. Similarly, Acyclovir (ACV) is converted into the triphosphate thereof (ACVTP), which selectively inhibits herpesvirus DNA polymerase. The first step in the activation of the nucleosides (Nu) consists of a monophosphorylation, leading to the corresponding monophosphate (NUMP). It is this first step which is the most selective.
In order to circumvent this key step of enzymatic monophosphorylation, it has already been proposed to adminster NuMPs directly, but their use for therapeutic purposes was contraried by the abovementioned limitations and drawbacks.
Compounds bearing a phosphate or phosphonate group have a negatively charged ionic nature at physiological pH. The therapeutic activity of such compounds is consequently limited, on account of the low diffusion of negatively charged compounds across biological lipid membranes. In particular, charged compounds do not diffuse efficiently across cell membranes, or indeed across the cerebral barrier, which are lipidic in nature. Moreover, such compounds are readily dephosphorylated by the action of phosphatase enzymes in the blood or on the cell membranes, which enzymes dephosphorylate the substrate compounds thereof. In general, charged phosphate or phosphonate compounds are poorly absorbed via oral administration.
It has been sought to convert mononucleotides into neutral phosphotriesters capable of crossing the cell membrane and of intracellular delivery of the corresponding mononucleotide phosphotriester (NUMP). Such an approach has been adopted by various authors for a number of years, but has proved to be disappointing. The derivatives obtained were in general either excessively toxic or of insufficient extracellular stability, and did not in the end result provide any enhancement of the biological activity.
Thus, the use of phosphorylated nucleoside structures comprising bioreversible protecting groups of acyloxymethyl or acyloxybenzyl type has been proposed, for antitumor nucleoside derivatives such as 5-fluorouracil, in WO patents No. 9,008,155 and 9,119,721. However, these compounds are of limited chemical stability, and generate toxic formaldehyde metabolites in vivo. Furthermore, they are sparingly soluble and the yield of their chemical preparation is low.
The aim of the present invention is thus to provide other types of bioreversible groups which may be combined especially with mononucleotide or other structures such that the biological activity thereof is enhanced, in particular as regards compounds derived from or analogous to nucleosides having antiviral activity, and which reversible groups do not have the abovementioned drawbacks.
The present invention proposes to use novel groups, characterized by the presence of —SIS— and/or —S/C═Z enzyme-labile bonds which lead, after enzymatic activation, to the formation of unstable intermediates that selectively release the corresponding monophosphate or monophosphonate.
More precisely, the subject of the present invention is the compound corresponding to the general formula I:
RO—P(═O)(OR)—Nu (I)
in which:
R is a radical —(CH 2 )n—S—X, where X represents a radical —C(═Z)(Y) or —S—U, and Z is O or S;
Y and U represent an alkyl, aryl or saccharide radical which is optionally substituted, in particular with an OH, SH or NH group; and
n is equal to 1 to 4, preferably 1 or 2;
Nu is a radical consisting of a residue of a biologically active compound or the dephosphorylated residue of a compound which is biologically active when it bears a phosphate or phosphonate group.
Moreover, the present invention also relates to the compound corresponding to the general formula Ia:
RS—P(═O)(QR)—Nu (Ia)
in which:
R is a radical —(CH 2 )n—W—X, where X represents a radical —C(═Z)(Y) or —S—U, and Z is O or S;
Q is O or S;
W is O or S;
Y and U represent an alkyl, aryl or saccharide radical which is optionally substituted, in particular with an OH, SH or NH group;
n is equal to 1 to 4, preferably 1 or 2; and
Nu is a radical consisting of a residue of a biologically active compound or the dephosphorylated residue of a compound which is biologically active when it bears a phosphate or phosphonate group.
When, in the formulas (I) and (Ia), Nu is linked to the phosphorus by a P—O bond, the compound of formulas (I) and (Ia) according to the invention bears a phosphate group and thus constitutes a phosphotriester compound.
When Nu is linked to the phosphorus by a P—C bond, the compound of formulas (I) and (Ia) according to the invention bears a phosphonate group.
The mechanisms of bioreversibility of the radicals R take place via enzymatic cleavage of the S—X or O—X bonds and release of the (CH 2 ) 2 —S residues, according to the mechanisms which are illustrated by the examples represented FIG. 1 and FIG. 9 .
For Y and U there are especially mentioned, as alkyl group, a C 1 to C 7 alkyl; as aryl group, phenyl and benzyl radicals, and, as saccharide radicals, glucose, mannose or rhamnose.
In one embodiment, when X represents SU, U preferably represents the radical —(CH 2 ) n1 —X 1 where X 1 represents H, OH, SH or NH 2 and n 1 is equal to 1 to 4, preferably 1 or 2.
There are especially mentioned the compounds (I) and (Ia) in which R represents —(CH 2 ) 2 —S—S—(CH 2 ) 2 —OH.
In another embodiment, when X represents —C(═Z)Y, Y appropriately represents CH 3 or tBu.
There are especially mentioned the compounds (I) and (Ia) for which R represents —(CH 2 ) n —S—C(═O)—CH 3 or (CH 2 ) n —S— C(═O)—tBu with n=1 or 2.
In an advantageous embodiment of the present invention, for the compounds (I) and (Ia), there are especially mentioned the compounds for which Nu represents a 5′ residue of a natural nucleoside or of a derivative of a natural nucleoside, which is therapeutically active or for which the 5′-(O)-monophosphate or 5′-(C)-monophosphonate is therapeutically active.
These compounds of formulas (I) and (Ia) generally have antiviral or antitumor activity.
The compounds of formulas (I) and (Ia) for which Nu represents a 5′ residue of 2′,3′-dideoxynucleoside or 2′,3′-didehydronucleoside are more particularly mentioned.
The compounds (I) and (Ia) for which Nu is a 5′ residue of ddU (dideoxyuridine), ddT (dideoxythymidine), ddC (dideoxycytidine), AZT (3′-azido-2′,3′-dideoxythymidine) and the derivatives thereof, especially those substituted on the pyrimidine base or at 2′ and 3′ of the saccharide ring, are more particularly mentioned among the compounds (I) and (Ia) derived from dideoxynucleosides having antiviral activity.
ddT, ddC or AZT are illustrations of the radicals Nu which represent a 5′ residue of a therapeutically active natural nucleoside derivative.
ddU is an illustration of the radicals Nu which represent a 5′ residue of a nucleoside derivative which is only active in phosphorylated form. ddU (dideoxyuridine) is not enzymatically monophosphorylated in vivo. Only the triphosphate thereof is a polymerase inhibitor and imparts antiviral activity thereto.
The compounds for which Nu represents a 5′ residue of the derivatives 5-fluorouridine or 5-fluoro-2′-deoxyuridine or 1-β-D-arabinofuranosylcytosine are especially mentioned among the compounds (I) and (Ia) having antitumor activity. These compounds illustrate the advantage of the functionalization according to the invention in order to circumvent the resistance acquired to certain nucleoside drugs when this resistance is due to a loss of their ability to be monophosphorylated, as is often the case in antitumor chemotherapy.
According to another embodiment variant of the invention, in the compounds (I) and (Ia) the radical Nu represents a nucleoside analog residue such as a carbonucleoside (nucleoside in which the oxygen of the saccharide ring is replaced by a carbon), a phosphononucleoside (nucleoside in which the oxygen at 5′ is replaced by a carbon) or a purine- or pyrimidine-based derivative of acyclonucleoside type, that is to say one which contains no saccharide ring, such as ACV (aciclovir), or a methoxyalkylpurine or pyrimidine radical of formula CH 2 —O-alkylpurine or -pyrimidine.
The compounds (I) and (Ia) for which Nu represents a methoxyalkylpurine or -pyrimidine radical are illustrations of the phosphonate compounds. In the particular case of phosphonylmethoxyalkylpurine or -pyrimidine antiviral compounds, PMEA, HPMPA or HPMPC are especially mentioned, the formulae of which are given in FIGS. 3 and 4.
Thus, the present invention relates in particular to compounds in which Nu is a 3-hydroxy-2-methoxypropylpurine or -pyrimidine radical of formula: —CH 2 —OCH(CH 2 OH)—CH 2 -purine or -pyrimidine or a 2-methoxyethylpurine or -pyrimidine radical of formula —CH 2 —O—C 2 H 4 -pyrimidine and, for example, the compounds (I) and (Ia) for which Nu is a methoxyethyladenine or 3-hydroxy-2-methoxypropylcytosine radical.
When Nu represents a dephosphonylated residue (dephosphated or dephosphonated) of a molecule which is biologically active when it is in phospate or phosphonate form, the functionalization according to the invention may enable the physicochemical and biophysical parameters of the said molecule comprising a phosphate or phosphonate group to be modified in general. Compounds (I) and (Ia) may then consist, for example, of a phosphopeptide or phospholipid compound.
When Nu represents a residue of a nucleoside, of a nucleoside derivative or of a nucleoside analog, the latter may be D or L enantiomers.
The compounds according to the invention may be prepared by processes known to those skilled in the art.
In particular, the subject of the present invention is a process for the preparation of the compounds according to the invention, characterized in that a compound of formulas (I) and (Ia) is prepared, in which compound the functional groups of R, and possibly of Nu, are protected by suitable protecting groups, followed by deprotection of the said functional groups of R, and possibly of Nu, in order to obtain the compounds of formula (I) and (Ia).
In particular, a compound of formula (II):
O − —P(═O) (O − )—Nu (II)
where Nu is possibly protected, is reacted in an appropriate manner with the compound of formula (III):
X—S—(CH 2 ) n —OH (III)
where X is protected, in order to obtain the said protected compound of formula (I), which is then deprotected.
In a particular embodiment, the reaction between the compounds of formula (II) and (III) takes place in the presence of a condensing agent such as MSNT, in pyridine.
Other preparation processes are illustrated in the examples which follow, in which other characteristics and advantages of the present invention will also appear.
BRIEF DESCRIPTION OF THE DRAWINGS
The numerous objects and advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying figures, in which:
FIG. 1 represents decomposition mechanisms for groups which are bioreversible under enzymatic activation. The same mechanism takes place for both groups R.
FIG. 2 represents the decomposition mechanism for the bioreversible group of the compound of Example 2.
FIG. 3 represents the formula of certain compounds according to the invention.
FIG. 4 represents a preparation scheme for compounds prepared in Example 1, and the formula of the compounds HPMPA and HPMPC.
FIG. 5 represents the preparation schemes for compounds prepared in Examples 2 and 3.
FIG. 6 represents the preparation scheme for compounds prepared in Example 4.
FIG. 7 represents the preparation scheme for compounds prepared in Examples 6-14.
FIG. 8 represents the preparation scheme for compounds prepared in Examples 15 and 16.
FIG. 9 represents the decomposition mechanism for the bioreversible group of the compound of Example 16A.
FIG. 10 illustrates anti HIV activity in cell cultures comparing compounds of Example 16A and 16B with similiar compounds of formula I.
DETAILED DESCRIPTION OF THE INVENTION
The advantage of this invention resides in the difference in stability of the mononucleotide phosphotriesters between extracellular and intracellular media; it is initially shown that the decomposition of one of the compounds described in the invention (Example 2) complies fully with the abovementioned criteria and occurs according to the mechanism shown FIG. 2 .
The “ISRP on line” HPLC technique (“On-line Internal Surface Reversed-Phase Cleaning: The Direct HPLC Analysis of Crude Biological Samples”, A. Pompon, I. Lefebvre and J. L. Imbach, Biochemical Pharmacology, 43,1769-1775 (1992) was used for this study, the compound studied being incubated respectively in culture medium (RPMI/10% inactivated serum) and in a total cell extract (CEM).
The compound of Example 2 has a half-life of 9 hours in culture medium and of less than 5 minutes in cell extract. The corresponding intracellular release of NUMP is corroborated by the demonstration of biological activity, whereas the constituent nucleoside is inactive.
Furthermore, insofar as the rate-determining step for activation of the phosphotriester into mononucleotide is highly dependent on the initial kinetics of enzyme hydrolysis, a variation in the nature of the enzymelabile groups leads to a modulation of the pharmacokinetic parameters of the drug and results in delayactions.
These data clearly confirm the advantage of the invention.
Thin layer chromatographies were performed on Merck 60F 254 silica plates (Art. 5554). Column chromatographies on silica gel were carried out with Merck 60 H silica (Art. 7736) or with RP2 Merck silanized silica (Art. 7719). Before analysis or lyophilization, the solutions were filtered on Millex HV-4 filter (Millipore).
The UV spectra were recorded on a UVIKON 810 spectrophotometer.
Mass spectra were taken on a JEOL JMS DX 300 apparatus by the FAB ionization method in positive or negative mode in a matrix of glycerol (GT), glycerol/thioglycerol (GT) or 3-nitrobenzyl alcohol (NBA).
Proton NMR spectra were recorded on a Varian EM 360 apparatus or on a Bruker AC 250 apparatus. The chemical shifts are expressed in ppm relative to the tetramethylsilane (TMS) signal. The multiplicity and the appearance of the signals observed by NMR are indicated by one (or more) letter(s): s (singlet), d (doublet), t (triplet), m (multiplet), b (broad). Phosphorus NMR spectra were recorded on a Bruker WP 200 SY apparatus with proton decoupling. The chemical shifts are expressed in ppm relative to the H 3 PO 4 signal which is taken as external reference.
EXAMPLE 1
O-(2′,3′-dideoxyuridin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate (1) (Scheme in FIG. 4)
2-Hydroxyethyl Acetyl Sulfide (5)
A solution of 1.0 ml (14 mmol) of thioacetic acid in 5 ml of toluene is treated with 0.90 ml (12 mmol) of iodoethanol in the presence of 1.7 ml (12 mmol) of 1,8-diazabicyclo-(5.4.0)-7-undecene (DBU) for 2 hours. The reaction medium is diluted with dichloromethane and washed with water. The organic phase is dried over sodium sulfate and evaporated. The crude product obtained is purified on a column of silica gel (eluent: methanol (0-4%) in dichloromethane) to give 1.2 g (85%) of 5 in the form of an oil.
5: 1 H NMR (DMSO-d 6 ): d=2.32 (s, 3H, CH 3 ); 2.91 (t, 2H, CH 2 S, J=6.6 Hz); 3.45 (pseudo q, 2H, CH 2 OH, J=6 Hz); 4.97 (t, 1H, OH) ppm.
O-(2′,1,3′-dideoxyuridin-5′-yl)hydrogenophosphonate (6)
A 1.5 M solution of phosphorous acid (165 ml, 247 mmol) in anhydrous pyridine is added to 5.25 g of 2′,3′-dideoxy-uridine (24.7 mmol) and is treated with 16.8 ml of pivaloyl chloride (136 mmol). After reaction for 3 hours, aqueous 1 M triethylammonium bicarbonate solution is added to neutralize the mixture and the solvent is evaporated off under reduced pressure. The oil obtained is chromatographed on a column of silica gel (eluent: methanol (0-35%) in dichloromethane) to give 6. The product is taken up in methanol and is filtered on a Millipore filter. Evaporation of the solvent gives 7.10 g (76%) of 6 (in triethylammonium form) which is sufficiently pure for use in the next step of the synthesis. A sample of higher purity is obtained after an additional purification by thin layer chromatography on silica gel, using a mixture of isopropanol, ammonia solution and water (8:1:1) as eluent. The product, in ammonium form, is extracted from the silica with methanol, the solvent is stripped off by evaporation and the residue is taken up in water, filtered on a Millipore filter and lyophilized.
6: LTV (H 2 O): Λ max =262 nm (e 9940); Λ min =230 nm (e 2080)
MS (negative FAB, GT); 275 (M) −
1 H NMR (DMSO-d 6 ); d=1.78-2.05 (m: 3H, H-2′,3′,3″); 2.18-2.45 (m, IH, H-2″); 3.65-3.95 (m, 2H, H-5′,5″); 4.11 (m, 1H, H-4″); 5.55 (d, 1H, H-5, J=8.1 Hz); 5.95 (dd, 1H, H-l′, J=6.8 and 3.8 Hz); 6.63 (d, 1E, HP, J=592 Hz); 7.87 (d, 1H, H-6, J=8.1 Hz) ppm 31 P NMR (DMSO-d 6 ): d=1.60 ppm.
O-(2′,3′-dideoxyuridin-5′-yl)-O,O′-bio(S-acetyl-2-thioethyl)phosphate (1)
A solution of 200 mg (0.530 mmol) of the hydrogenophosphonate 6 of 2′,3′-dideoxyuridine in 5 ml of pyridine is treated with 196 μl of pivaloyl chloride for 30 minutes. 159 mg (1.33 mmol) of 2-hydroxyethyl acetyl Sulfide (5) are added and the reaction is left stirring for 2 hours. The phosphate formed is oxidized using 2% iodine solution in a pyridine-water mixture (98:2) until a persistent coloration is obtained (7-8 ml). The solvent is evaporated off under reduced pressure. The crude product obtained is co-evaporated with toluene and chromatographed on a column of silica gel (eluent: methanol (0-6%) in dichloromethane) to give 65 mg (25%) of compound 1 in the form of an oil.
1: UV (EtOH): Λ max =262 nm (e 9400); Λ min =230 nm (e 2500)
MS (positive FA.B): 497 (M+H) +
1 H NMR (DMSO-d 6 ):d=1.73-2.13 (m, 3H, H-2′,3′,3″) 2.20-2.4 (m, 1H, H-2″); 2.356 and 2.360 (s and s, 3H and 3H. 2 CH 3 ); 3.13 (t, 4H, 2 CH 2 S, J=6.4 Hz); 4.00-4.26 (m, 7H, H-4′,5′,5″and 2 CH 2 C H 2 OP); 5.60 (d, 1H, H-5, J=8.1 Hz); 6.01 (dd, 1H, H-l′, J=4.2 and 7.0 Hz); 7.64 (d, 1H, H-6, J=8.1 Hz); 11.3 (bs, 1H, NHCO) ppm.
31 P NMR (DMSO-d 6 ): d=−1.21 ppm
EXAMPLE 2
O,O′-Bis(S-(2-hydroxyethylsulfidyl)-2-thioethyl)-o-(2′,3′-dideoxyuridin-5′-yl)phosphate (2). (Scheme in FIG. 5)
O,O′-Bis (S-(O-(4-methoxytrityl)-2-oxethylsufidyl)-2-thioethyl)phosphate (8)
To a solution of 0.910 g (13.4 mmol) of imidazole in 18 ml of pyridine at 0 C. is added 0.406 ml (4.45 mmol) of phosphorus oxychloride. The mixture is stirred for 30 minutes at room temperature, then added to 3.80 g (8.91 mmol) of mono-O-(4-methoxytrityl)dithiodiethanol (7). After 18 hours, the reaction mixture is treated with 1 M triethylammonium acetate solution. The reaction products are extracted with dichloromethane and the organic phase is washed with water, dried over sodium sulfate, concentrated under reduced pressure and co-evaporated with toluene. Purification on a column of silica gel (eluent: methanol (0-10%) in dichloromethane) gives 2.2 g (48%) of 8 in the form of the triethyl-ammonium salt.
8: MS (negative FAB, NBA): 913 (M − ).
1 H NMR (DMSO-d 6 ) 1.14 (t, 9H, (C H 3 C H 2 ) 3 NH 1 J=7.3 Hz); 2.78 (t, 4H, 2 SC H 2 C H 2 OP, J=6.4 Hz); 2.86 (t, 4H, 2 SC H 2 C H 2 OMTr, J=6 Hz); 2.99 (q, 6H, (CH 3 C H 2 ) 3 NH + , J=7.3 Hz); 3.21 (t, 4H, 2 C H 2 OMTr, J=5.9 Hz); 3.71 (s, 6H, 2 CH 3 O); 3.87 (m, 4H, 2 C H 2 OP); 6.82-7.45 (m, 28H, 2 Tr) ppm.
31 p NMR (DMSO-d 6 ): −2.70 ppm.
O,O′-Bis (S-(2-hydroxyethylsulfidyl)-2-thioethyl)-O-(2′,3′-dideoxyuridin-5′-yl)phosphate (2)
A mixture of 666 mg (0.655 mmol) of 8 and 139 mg (0.656 mmol) of 2′,3′-dideoxyuridine in 5 ml of pyridine is treated with 486 mg (1.64 nmol) of 1-(2-mesitylene-sulfonyl)-3-nitro-1,2,4-triazole. After 30 hours, the reaction mixture is diluted with dichloromethane and washed with aqueous 1M triethylammonium acetate solution and then with water. The organic phase is dried over sodium sulfate, concentrated under reduced pressure, coevaporated with toluene and chromatographed on a column of silica gel (eluent: methanol (0-4%) in dichloromethane). The partially purified protected phosphotriester is treated with 5 ml of the acetic acid/water/methanol mixture (8:1:1) for 24 hours. The solvents are stripped off by evaporation under reduced pressure and the oil obtained is co-evaporated with toluene. Purification on a column of silica gel (eluent: methanol (0-6%) in dichloromethane) followed by purification on a column of silanized silica (eluent: ethanol (0-40%) in water) gives 52 mg (14%) of compound 2 after lyophilization in dioxane.
2: LTV (EtOH): Λ max 261 nm (∈ 9900); Λ min 231 nm (∈ 3100)
MS (positive FA.B, GT): 565 (M+H) + : 489 (M−SCH 2 CH 2 OH+2H) + ; 429 (M−HOCH 2 CH 2 SSCH 2 CH 2 +2H) + .
1 H NMR (DMSO-d 6 ): 1.63-1.9 (m, 1H, H-3′); 1.9-2.10 (m, 2H, H-2′3″); 2.33-2.40 (m, 1H, H-2″); 2.80 (t, 2H,HOCH 2 C H 2 S, J=6.4 Hz); 2.81 (t, 2H, HOCH 2 C H 2 , J=6.4 Hz); 3.00 (t, 4H, 2 SC H 2 CH 2 OP, J=6.3 Hz); 3.61 (pseudo q, 4H, 2, HOC H 2 , J=6 Hz), 4.07-4.32 (m, 7H, H-4′,5′,5″ and 2 CH 2 C H 2 OP); 4.89 (t, 2H, 2 HO, J=4.9 Hz); 5.598 (d, 1H, H-5, J=8.1 Hz); 5.604 (d, 1H, H-5, J=8.1 Hz); 6.00 (dd, 2H, 2H-1′, J=4.1 and 7.9 Hz);7.65 (d, 2H, 2H-6, J=8.0 Hz); 11.31 (bs, 1H, NHCO)ppm.
31 p NMR (DMSO-d 6 ): −0.880 ppm
EXAMPLE 3
O,O′-Bis(S-(2-hydroxyethylsulfidyl)-2-thioethyl)-O-(3′azido-3′-deoxythymidin-5′-yl)phosphate (3). (Scheme in FIG. 5)
A mixture of 666 mg (0.655 mmol) of 8 and 193 mg (0.722 mmol) of 3′-azido-3′-deoxythymidine in 5 ml of pyridine is treated with 486 mg (1.64 mmol) of 1-(2-mesitylenesulfonyl)-3-nitro-1,2,4-triazole. After 24 hours, 194 mg (0.656 mmol) of 1-(2-mesitylenesulfonyl)-3-nitro-1,2,4-triazole are added and the reaction is left for a further 24 hours. The reaction mixture is then diluted with dichloromethane and washed with aqueous 1M triethylammonium acetate solution and then with water. The organic phase is dried over sodium sulfate, concentrated under reduced pressure, co-evaporated with toluene and chromatographed on a column of silica gel (eluent: methanol (O-2%) in dichloromethane). The partially purified protected phosphotriester is treated with 5 ml of the acetic acid/water/methanol mixture (8:1:1) for 24 hours. The solvents are stripped off by evaporation under reduced pressure and the oil obtained is co-evaporated with toluene. Purification on a column of silica gel (eluent: methanol (0-6%) in dichloromethane) gives 130 mg (29%) of compound 3 after lyophilization in dioxane.
3: UV (EtOH): Λ max 264 nm (∈ 9600), Λ min 234 nm (∈ 2100)
MS (positive FAB, GT): 620 (M+H) + ; 544 (M−SCH 2 CH 2 OH+2H) =
1H NMR (DMSO-d 6 ): 1.80 (s, 3H, CH 3 ); 2.26-2.5 (m, 2H, H-2′2″); 2.796 (t, 2H, HOCH 2 C H 2 S, J=6.4 Hz); 2.802 (t, 2H, HOCH 2 C H 2 S, J=6.4 Hz); 2.99 (t, 4H, 2 SC H 2 C H 2 OP, J=6.3 Hz); 3.61 (pseudo q, 4H, 2 HOC H 2 ′ J=6 Hz); 4.02 (m, 1H, H-4′); 4.09-4.44 (m, 6H, H-5′,5″ and 2 CH 2 C H 2 OP); 4.48 (m, 1H, H-3′); 4.90 (t, 2H, 2 HO, J=5.3 Hz); 6.14 (t, 1H, H-l′, J=6.6 Hz); 7.49 (s, 1H, H-6); 11.37 (bs, 1H, NHCO) ppm.
31 P NMR (DMSO-d 6 ): −0.954 ppm
EXAMPLE 4
9-(2-(O,O′-Bis(S-(2-hydroxyethylsulfidyl)-2-thioethyl)phosphonylmethoxy-ethyl)adenine (4). (Scheme in FIG. 5)
N6-(4-Methoxytrityl)-9-(2-diethoxyphosphonylmethoxy ethyl)adenine (10)
A solution of 3.93 g (11.9 mmol) of 9-(diethoxyphosphonylmethoxyethyl)adenine (9) (A. Holy et al., Collection Czechoslovak Chem. Commun. 52 2792, 1987) and 146 mg (1.19 mmol) of 4-dimethylaminopyridine in 50 ml of dichloromethane is treated with 3.31 ml (23.8 mmol) of triethylamine and 7.35 g (23.8 mmol) of 4-methoxytrityl chloride for 4 hours. The reaction mixture is then diluted with dichloromethane and washed with aqueous sodium hydrogen carbonate solution and then with water.
The organic phase is dried over sodium sulfate and concentrated under reduced pressure. Chromatography on a column of silica gel (eluent: methanol (0-3%) in dichloromethane) allows 5.43 g (84%) of compound 10 to be isolated.
10: UV (EtOH): Λ max 275 nm (∈ 27200), Λ min 246 nm (∈ 11200)
MS (negative FAB, GT) 601 (M−H) − ; 406 (A mTr ) − ; 328 (M−MTr)−
1 H NMR (DMSO-d 6 ): 1.10 (t, 6H, 2 C H 3 C H 2 , J=7.0 Hz); 3.71 (s, 3H, CH 3 O), 3.80-3.98 (m, 4H. PC H 2 and CH 2 C H 2 ); 3.88 (q, 4H, 2 CH 3 C H 2 ′ J=8 Hz); 4.33 (t, CH 2 C H 2 ′ J=4.8 Hz) 6.80-7.37 (m, 14H, Tr); 7.91 (s, IH, H-8); 8.18 (s,H-2) ppm.
31 P NMR (DMSO-d 6 ): 21.35 ppm.
N 6 -(4-Methoxytrityl)-9-(2-phosphonylmethoxyethyl)adenine (11)
A solution of 5.00 g (8.31 mmol) of 10 in 29 ml of acetonitrile is treated with 3.29 ml (24.9 mmol) of trimethylsilyl bromide for 14 hours. The excess reagent and the solvent are stripped off by evaporation under reduced pressure. The oil obtained is taken up in triethylammonium bicarbonate and concentrated under reduced pressure. Purification is performed by chromatography on a column of silica gel (eluent: methanol (0-50%) in dichloromethane). After filtration in solution in di-chloromethane, 3.4 g (63%) of 11 are isolated in the form of a mixed salt of acid and triethylammonium (1:1).
11: MS (negative FAB, GT): 544 (M−H) − : 272 (M−MTr) − .
1 H NMR (DMSO-d 6 ): 1.11 (t, 9H, (C H 3 CH 2 )NH + , J=7.3 Hz); 2.96 (q, 6H, (C H 3 C H 2 )NH + , J=7.3 Hz); 3.34 (d, 2H, PCH 2 , J=8.4 Hz); 3.68 (s, 3H, CH 3 O); 3.8 (m, 2H, C H 2 CH 2 ); 4.27 (t, CH 2 C H 2 , J=4.5 Hz); 6.65-7.35 (m, 14H, Tr); 7.83 (s, 1H, H-8); 8.31 (s, 1H, H-2) ppm.
31P NMR (DMSO-d 6 ): 11.40 ppm.
N6-(4-Methoxytrityl)-9-(2-O,O′-bio(S-(O-(4-methoxytrityl)-2-oxethylaufidyl)-2-thioethyl))phosphonylmethoxyethyl)adenine (12)
A mixture of 296 mg (0.458 mmol) of 11 with 977 mg (2.29 nmol) of mono-O-(4-methoxytrityl) dithiodiethanol (7) in 5 ml of pyridine is treated with 341 mg (1.15 mmol) of 1-(2-mesitylenesulfonyl)-3-nitro-1,2,4-triazole. After 3 days, the reaction mixture is diluted with dichloromethane and washed with saturated aqueous sodium hydrogen carbonate solution and then with water. The organic phase is dried over sodium sulfate, concentrated under reduced pressure, co-evaporated with toluene and chromatographed on a column of silica gel (eluent: methanol (0-5%) in dichloromethane) to give 330 mg (53%) of 12.
12: UV (EtOH): Λ max 275 nm (∈ 28200), Λ min 253 nm (∈ 18300)
MS (negative FAB, NBA) 1360 (M−H)−: 952 (M−MtrOCH 2 CH 2 SSCH 2 CH 2 )−.
1 H NMR (DMSO-d 6 ): 2.75 (t, 4H, 2 SC H 2 CH 2 OP, J=6.3 Hz) 2.86 (t, 4H, 2 C H 2 CH 2 OMTr, J=5.9 Hz); 3.19 (t, 4H, 2 C H 2 OMTr, J=6.0 Hz); 3.68 (s, 3H, CH 3 O); 3.69 (s, 6H, 2 CH 3 O); 3. 83 (m, 4H, PCH 2 and CH 2 CH 2 ); 4.05 (m, 4H, 2 CH 2 OP); 4.28(t, 2H, CH 2 CH 2 , J=4.6 Hz); 6.87 -7.45 (m, 42H, 3 Tr); 7.88 (s, 1H, H-8); 8.12 (s, 1H, H-2)ppm.
31 P NMR (DMSO-d 6 ): 22.09 ppm.
9-(2-(O,O′-Bis(S-(2-hydroxyethylsulfidyl)-2-thioethyl)phosphonylmethoxyethyl)adenine (4)
The phosphotriester 12 (290 mg, 0.213 mmol) is treated with 15 ml of the acetic acid/water/methanol mixture (8:1:1) for 15 hours. The solvents are stripped off by evaporation under reduced pressure and the oil obtained is co-evaporated with toluene. Purification on a column of silica gel (eluent: methanol (0-8%) in dichloromethane) gives 116 mg (90%) of compound 4 after lyophilization in the water/dioxane mixture.
4: LTV (EtOH): Λ max 260 nm (∈ 14700); Λ min 228 nm (∈ 3600).
MS (positive FAB, GT): 545 (M+H) +
1 H NMR (DMSO-d 6 ): 2.80 (t, 4H, 2 SC H 2 CH 2 OP, J=6.4 Hz); 2.91 (t, 4H, 2 SC H 2 CH 2 OH, J=6.4 Hz); 3.61 (pseudo q, 4H, 2 C H 2 OH,J=6 Hz); 3.91 (t, 2H, C H 2 CH 2 , J=5.1 Hz) 3.95 (d, 2H, PCH 2 , 8.2 Hz); 4.15 (m, 4H, 2 C H 2 OP); 4.32 (t, 2H, CH 2 C H 2 , J=5. 0 Hz); 7.20 (bs, 2H, NH 2 ); 8.08 (s, 1H, H-8); 8.14 (s, 1H, H-2) ppm.
31 P NMR (DMSO-d 6 ): 22.24 ppm.
EXAMPLE 5
Evaluation of the Anti-HIV I Activity of CEM Cells and MT-4 Cells
HIV=Human immunodeficiency virus
MT-4=Human leukemia T cell
CEM=Human lymphoblastoid T cell
HIV-1 replication (LAI isolate) in CEM cells is measured by assaying the reverse transcriptase (RTase) in the culture supernatant after infection for 5 days. This activity reflects the presence of the virus released by the cells. After adsorption of the virus, the test compounds are added, at various concentrations, to the culture medium.
Antiviral activity is expressed as the lowest concentration of compound which reduces the production of RTase by at least 50% (ED 50 ).
The toxic effect on non-infected CEMs is assessed by a calorimetric reaction based on the capacity of living cells to reduce 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide into formazan after incubation for 5 days in the presence of various concentrations of the compounds. The results are expressed as the lowest concentration of compound which results in at least 50% inhibition of the formation of formazan (CD 50 ).
The compounds used as examples in this invention have the following anti-HIV activities:
Compound 1:
ED 50
CEM-TK-,
4.10 −6 M
(CD 50 7.10 −5 M)
CEM-SS,
5.10 −6 M
(CD 50 9.10 −5 M)
MT4,
2.10 −6
(CD 50 9.10 −5 M)
Compound 2:
ED
CEM-TK-,
8.10 −6 M
(CD 50 8.10−5 M)
CEM-SS,
6.10 −5 M
(CD 50 10 −4 M)
Compound 3:
ED 50
CEM-TK − ,
7.10 −6 M
(CD 50 8.10 −5 M)
CEM-SS,
7.10 −10 M
(CD 50 8.10 −5 M)
MT4
10 −9 M
(CD 50 8.10 −5 M)
Compound 4:
ED 50
CEM-TK − ,
8.10−8 M
(CD 50 4.10 −5 M)
CEM-SS,
3.10−6 M
(CD 50 > 10 −4 M)
MT4,
8.10−7 M
(CD 50 2.10 −5 M)
This set of data shows that there has indeed been intracellular release of the nucleoside monophosphate.
EXAMPLE 6
O,O′-Bis(S-acetyl-2-thioethyl)-N,N-diisopropylphosphoramidite
To a stirred solution of N,N-diisopropylphosphorodichloridate (4.04 g, 20 mmol) in tetrahydrofuran (150 ml) at −78° C. was added dropwise over 45 minutes a solution of S-acetylthioethanol (4.81 g, 40 mmol) and triethylamine (5.53, 40 mmol) in tetrahydrofuran (100 ml). The resulting reaction mixture was stirred for 2 hours at ambient temperature then filtered. The filtrate was concentrated under vacuum and the residue was diluted with cyclohexane and filtered. The filtrate was concentrated to a residue under vacuum, Diluted with cyclohexane, filtered and concentrate again. The final residue was chromatographed on a silica gel column. The column was eluted with a gradient of ethyl acetate in cyclohexane (0→20%) containing 5% triethylamine to obtain the title compound, O,O′-bis(S-acetyl-2-thioethyl-N,N-diisopropylphosphoramidite (5.3 g, 72%).
Mass Spec (FAB positive, GT): 370 (M+H) + , 103 [CH 3 C(O)SCH 2 CH 2 ] + .
NMR 1 H (DMSO-d 6 ): 3.70-3.47 (m, 6H, 2 C H 2 OP, 2 C H (CH 3 ) 2 ); 3.04 (t, 4H, 2SC H 2 J=6.4 Hz); 2.32 (s, 6H, 2C H 3 COS); 1.10 (d, 12H, 2 CH(C H 3 ) 2 ), J=6.8 Hz) ppm. NMR 31 p (DMSO-d 6 ): 147.9 ppm (q).
EXAMPLE 7
General Procedure For O-(2′,3′-dideoxynucleosid-5′-yl)-O′-O″-bis(S-acetyl-2-thioethyl)phosphates
To a solution of a 2′,3′-dideoxynucleoside [AZT (0.1 g, 0.37 mmol); ddA (0.05 g, 0.5 mmol); ddI (0.12 g, 0.5 mmol); or ddT (0.11 g, 0.5 mmol)] and O,O′-bis(S-acetyl-2-thioethyl)-N,N′-diisopropylphosphoramidite (1.2 eq.) in a mixture of tetrahydofuran/dimethylforamide (1:1, v/v, 5 ml per mmol) was added sublimed tetrazole (3.0 eq). After 30 min of stirring at ambient temperature the reaction mixture was cooled to −40° C. and a suspension of 3-chloroperbenzoic acid (1.3 eq) in dichloromethane (2 ml per mmol) was added. After stirring for one hour at ambient temperature the excess peracid was reduced with an aqueous solution of 10% sodium thiosulfate. The crude residue was diluted with dichloromethane and extracted with a saturated aqueous solution of sodium bicarbonate. The organic phase was wash with water, dried over sodium sulfate, filtered and evaporated under vacuum. The residue was chromatographed on a silica gel column eluted with a step gradient of methanol in dichloromethane to give the title bis(SATE)phosphotriesters as pure products.
EXAMPLE 8
O-(2′,3′-Dideoxy-3′-azidothymidin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate [Bis(SATE)AZTMP]
Prepared as per the above general procedure to give 0.11 g (53%) of the title compound.
UV (EtOH): Λ max 264 nm (ε 9800) λ min 246 nm (ξ 6500).
Mass Spec. (FAB positive, GT) 552 (M+H) + , (FAB negative, GT): 550(M−H) − .
NMR 1 H (DMSO-d6): 11.36 (sl, 1H, NH-3); 7.46 (d, 1H, H-6, J H-6, CH3-5 =0-7 Hz); 6.13 (t, 1H, H-1′, J H1′,2″ =6.7 Hz) 4.46 (m, 1H, H-3′); 4.20 (m, 2H, H-5′,5″); 4.03 (m, 5H, H-4′, CH 2 —C H 2 —O); 3.12 (t, 4H, S—C—H 2a -CH 2b , J Ha,Hb =6.3 Hz); 2.42 (m, 8H, H-2′,2″, C H 3 —CO); 1.78 (s, 3H, CH 3 -5) ppm.
EXAMPLE 9
O-(2′,3′-Dideoxyadenosin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate [Bis(SATE)ddAMP]
Prepared as per the above general procedure to give 0.65 g (50%) of the title compound.
UV (EtOH): Λ max 260 nm (ε 12000), 229 nm (ε 8600), ξmin 240 nm (ε 7200), 223 nm (ε 7900).
Mass Spec. (FAB positive, GT): 520 (M+H) + , 136 (BH 2 ) + ; (FAB negative, GT) 416 (M−CH 3 C(O)SCH 2 CH 2 ) − , 134 (B) − .
NMR 1 H (DMSO-d6): 8.25 & 8.13 (2s, 1H & 1H, H-2 & H-8); 7.24 (s, 2H, NH2); 6.24 (t, 1H, J=5.4 Hz, H-1′); 4.28 (m, 1H, H-4′); 4.18-4.03 (m, 2H, H-5′ & H-5″); 3.96 (q, 4H, 2 S—CH 2 —C H 2 —O); 3.06 (t, 4H, J=6.3 Hz, 2 S—C H 2 -CH 2 —O); 2.48 (m, 2H, H-2′ & H-2″); 2.32 & 2.31 (2s, 3H & 3H, 2 CH 3 ) ppm.
NMR 31 P (DMSO-d 6 ) 0.78 ppm.
EXAMPLE 10
O-(2′,3′-Dideoxyinosin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate [Bis(SATE)ddIMP]
Prepared as per the above general procedure to give 0.21 g (81%) of the title compound.
UV (EtOH) Λ max 242 nm (ε 14700), 235 nm (ε 14900) shoulder 266 nm (ε 5800) & 248 nm (ε 13400).
Mass Spec. (FAB positive, GT): 521 (M+H) + , 137 (BH 2 ) + , 103 (CH 3 C(O)SCH 2 CH 2 ) + ; (FAB negative, GT): 519 (M−H) 31 , 135 (B) − .
NMR 1 H (DMSO-d6): 12.36 (s, 1H, NH-1); 8.21 (s, 1H, H-2); 8.04 (s, 1H, H-8); 6.22 (m, 1H, H-1′); 4.28 (m, 1H, H-4′); 4.20-4.02 (m, 2H, H-5′ & H-5″); 3.97 (m, 4H, 2 S—CH 2 —C H 2 —OP); 3.07 (t, 4H, J=6.4 Hz, 2 S—C H 2 —C H 2 ); 2.49-2.42 (m, 2H, H-2′ & H-2″); 2.33 (s, 3H, CH 3 COS), 2.32 (s, 3H, CH 3 COS), 2.15-2.02 (m, 2H, H-3′ & H-3″) ppm.
NMR 31 P (DMSO-d 6 ) 0.77 (m) ppm.
EXAMPLE 11
O-(2′,3′-Dideoxythymidin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate [Bis(SATE)ddTMP]
Prepared as per the above general procedure to give 0.23 g (91%) of the title compound.
UV (EtOH) λ max 266 nm (ε 8800), λ min 246 nm (ε 5400).
NMR 1 H (DMSO-d6): 11.29 (s, 1H, NH-3); 7.47 (d, 1H, H-6; J=1.0 Hz); 6.01 (m, 1H, H-1′), 4.20-4.11 (m, 3H, H-4′,H-5′,5″); 4.04 (m, 4H, 2 CH 2 —C H 2 —OP); 3.11 (t, 4H, S—C— H 2a —CH 2b , J=6.3 Hz); 2.34 (s, 3H, C H 3 —COS); 2.33 (s, 3H, C H 3 —COS); 2.33-2.25 (m, 1H, H-2″); 2.00-1.90 (m, 3H, H-2″,3′,3″); 1.78 (d, 3H, CH 3 -5, J=0.6 Hz) ppm.
NMR 31 P (DMSO-d 6 ) 0.56 ppm.
EXAMPLE 12
N 6 -(4-Methoxytrityl)-9-(2-(O,O′-bis(S-acetyl-2-thioethyl)phosphonylmethoxyethyl)adenine [Bis(SATE)PMEA-MTr]
To a solution of N 6 -(4-methoxytrityl)-9-(2-phosphonylmethoxyethyl)adenine (compound 11) as a mixture of triethylammonium salts (0.25:0.75, 0.3 g, 0.43 mmol), 1-(2-mesitylenesulfonyl)-3-nitro-1,2,4-triazole (0.41 g, 1.38 mmol) in anhydrous pyridine (6 ml) was added S-acetylthioethanol (0.33 g, 2.77 mmol). The reaction mixture was stirred overnight at ambient temperature and then neutralized with an aqueous triethylammonium bicarbonate (1M, pH 7.5, 4 ml). Chloroform and water were added, the organic phase was decanted, dried over sodium sulfate, filtered and evaporated under vacuum. The residue was chromatographed on a silica gel column eluted with a gradient methanol in dichloromethane (0→2%) to give the title compound, bis(SATE)PMEA-MTr (0.15 g, 50%), as an oil.
Mass Spec. (FAB positive, GT): 750 (M+H) + .
NMR 1 H (DMSO-d6): 8.15 & 7.90 (2s, 1H & 1H, H-2 & H-8); 7.31-6.81 (m, 15H, trityl & NH); 4.32 (t, 2H, J=4.7 Hz, CH 2 N); 3.99-3.84 (m, 8H, 2 S—CH 2 —C H 2 —O, CH 2 —P, C H 2 —CH 2 —N); 3.70 (s, 3H, OCH 3 ); 3.01 (t, 4H, J 6.4 Hz, S—C H 2 —CH 2 —O); 2.30 (s, 6H, 2 CH 3 ) ppm.
NMR 31 p (DMSO-d 6 ) 22.51 ppm.
EXAMPLE 13
9-(2-(O,O′-Bis(S-acetyl-2-thioethyl)phosphonylmethoxyethyl)-adenine [Bis(SATE)PMEA]
A solution of bis(SATE)PMEA MTr (0. 21 g, 0.28 mmol) in acetic acid:water:methanol (8:1:1, v/v/v, 22 ml) was stirred overnight at ambient temperature. The reaction mixture was evaporated and the residue co-evaporated with 100% ethanol and dichloromethane. The residue was chromatographed on a silica gel column to give pure bis(SATE)PMEA (0.079 g, 59%). m.p. 66° C. (crystallized from toluene).
UV (EtOH) λ max 260 nm (ε 14200), 230 nm (ε 10400) λ min 240 nm (ε 9200), 223 nm (ε 9800).
Mass Spec. (FAB positive, GT): 570 (M+G+H) + , 478 (M+H) + ; (FAB negative, GT): 374 (M−CH 3 C(O)SCH 2 CH 2 ) − .
NMR 1 H (DMSO-d6): 8.12 & 8.06 (2s, 1H & 1H, H-2 & H-8); 7.17 (s, 2H, NH 2 ); 4.31 (t, 2H, J=5.0 Hz, CH 2 N); 4.00-3.86 (m, 8H, 2 S—CH 2 —C H 2 O, CH 2 —P, C H 2 —CH 2 —N); 3.03 (t, 4H, J=6.4 Hz, 2 S—C H 2 —CH 2 —O); 2.33 (s, 6H, 2 CH 3 ) ppm.
NMR 31P (DMSO-d 6 ) 22.53 ppm.
EXAMPLE 14
Evaluation of the Anti-HIV 1 Activity on Cem Cells and MT-4 Cells of Bis(SATE)phosphotriesters of AZT, ddA, ddI, ddT and PMEA
The compounds were tested as described in Example 5 above.
AZT
ED 50
CEM-TK
>10 −4 M
(CD 50 > 10 −4 M)
CEM-SS
4.8 10 −9 M ±
(CD 50 > 10 −4 M)
2.4 10 −9
MT-4
1.8 10 −8 M ±
(CD 50 > 10 −4 M)
0.6 10 −8
Bis(SATE)AZTMP
ED 50
CEM-TK −
3.9 10 −8 M
(CD 50 ND)
CEM-SS
2.2 10 −8 M
(CD 50 ND)
MT-4
7.8 10 −8 M
(CD 50 7.6 10 −5 M)
ddA
ED 50
CEM-TK −
1.1 10 −6 M
(CD 50 > 10 −4 M)
CEM-SS
5.4 10 −7 M ±
(CD 50 > 10 −4 M)
1.1 10 −7
MT-4
10 −5 M
(CD 50 > 10 −4 M)
Bis(SATE)ddAMP
ED 50
CEM-TK −
7.7 10 −10 M
(CD 50 > 10 −5 M)
CEM-SS
5.6 10 −10 M ±
(CD 50 2.4 10 −5 M) ±
3.4 10 −10
0.1 10 −5
MT-4
1.1 10 −8 M ±
(CD 50 1.6 10 −5 M) ±
0.8 10 −8
0.9 10 −5
ddI
ED 50
CEM-TK −
9.5 10 −7 M
(CD 50 > 10 −4 M)
CEM-SS
4.3 10 −6 M ±
(CD 50 > 10 −4 M)
2.0 10 −6
MT-4
1.1 10 −5 M ±
(CD 50 > 10 −4 M)
0.2 10 −5
Bis(SATE)ddIMP
ED 50
CEM-TK-
3.0 10 −7 M
(CD 50 > 10 −4 M)
CEM-SS
1.2 10 −6 M ±
(CD 50 > 10 −4 M)
0.6 10 −6
MT-4
3.4 10 −6 M ±
(CD 50 > 10 −4 M)
1.1 10 −6
ddT
ED 50
CEM-TK −
>10 −4 M
(CD 50 > 10 −4 M)
CEM-SS
4.0 10 −6 M
(CD 50 > 10 −4 M)
MT-4
ND
(CD 50 ND)
Bis(SATE)ddTMP
ED 50
CEM-TK −
5 10 −7 M
(CD 50 > 10 −4 M)
CEM-SS
1.7 10 −6 M
(CD 50 8.5 10 −5 M)
MT-4
ND
(CD 50 ND)
In the same manner as was seen for the activities exhibited in Example 5, the anti HIV activity of the above listed bis(SATE) derivatives show increases of up to ⅓ log units compared to their parent nucleosides (compare AZTMP and ddTMP to the parent nucleosides AZT and ddT, respectively). This increase in activity shows that there was intercellular release of the nucleoside monophosphate.
For Examples 15 and 16 below, 1 H NMR were recorded using a Bruker AC 250 or a Bruker AC 400 spectrometer at ambient temperature in CDCl 3 . Chemical shifts are given in δ-values referenced to the residual solvent peak (7.26 ppm). Deuterium exchange, decoupling and COSY experiments were performed in order to confirm proton assignments. 31 P NMR spectra were recorded at ambient temperature on a Bruker AC 250 spectrometer at 101.2 MHz with proton decoupling. Chemical shifts are reported relative to external H 3 PO 4 . 31 C NMR spectra were measured on a Bruker AC 400 spectrometer at 100.6 MHz with proton decoupling using CDCl 3 (77.00 ppm) as internal standard. Coupling constants, J, are reported in hertz. FAB mass spectra were reported in the positive-ion or negative-ion mode on a JEOL DX 300 mass spectrometer operating with a JMA-DA 5000 mass data system using thioglycerol/glycerol (1:1, v/v, G-T) as matrix. Xe atoms were used for the gun at 3 kV with a total discharge current of 20 mA. UV spectra were recorded on an Uvikon 810 (Kontron) spectrometer in ethanol (95%).
TLC was performed on precoated aluminum sheets of silica gel 60 F 254 (Merck), visualization of products being accomplished by UV absorbance followed by charring with 5% ethanolic sulfuric acid with heating; phosphorus-containing compounds were detected by spraying with Hanes molybdate reagent (Hanes et. al., Nature, 154, 1107-1112, 1949). Column chromatography was carried out on silica gel 60 (Merck).
High-performance liquid chromatography (HPLC) studies were carried out on a Waters Assoc. unit equipped with a model 616 pump system, a model 600S system controller, a model 996 photodiode array detector and a Millennium data workstation.
The column was a reverse phase analytical column (Macherey-Nagel, C 18 , 150×4.6 mm, 5 μm) protected by a prefilter and a precolumn (Nucleosil, C 18 , 5 μm). The compound to be analyzed was eluted using a linear gradient of 0% to 80% acetonitrile in 50 mM triethylammonium acetate buffer (pH 7) programmed over a 40 min period with a flow rate of 1 ml/min and detection at 260 nm.
Evaporation of solvents was carried out on a rotary evaporator at 40 °C. or lower under reduced pressure. Dichloromethane and 2-mercaptoethanol were distilled over calcium hydride and acetonitrile was dried over phosphorus pentoxide. Anhydrous N,N-dimethylformamide (Fluka) was used as supplied. All solvents used in reactions involving trivalent phosphorus compounds were degased by an argon stream before use. All reactions were carried out under rigorous anhydrous conditions under an argon atmosphere.
Tris(pyrrolidino)phosphine was prepared as described by Wiesler at al. (Wiesler et al., Methods in molecular biology: Protocols for nucleotides and analogs (S. Agrawal Ed.), Humana Press Inc., Totowa, N.J., Vol. 20, 1991-206, 1993. d4T and ddA were supplied by Sigma (D1413) and Fluka (36769) respectively and were dried over P 2 O 5 under reduced pressure ar RT prior to use. Sublimed 1-H-Tetrazole was purchased from Sigma and used as supplied. Elemental sulfur and trimethylacetic anhydride were purchased from Aldrich, tert-butyl hydroperoxide (3M in toluene) from Fluka.
EXAMPLE 15
2-Mercaptoethyl-1-pivaloate
The title compound was prepared by adapting a method described by Miles et al., J. Chem. Soc., 817-826, 1952. Trimethylacetic anhydride (5.8 ml, 28.5 mmol) was added dropwise to a mixture of 2-mercaptoethanol (2.0 ml, 28.5 mmol) and sulfuric acid in acetic acid (0.09 ml, 10%, v/v) at 0° C. The solution was heated for 1h at 60-65° C. and stirred during 3 h at room temperature. After dilution with diethylether (40 ml), the reaction mixture was neutralized with saturated NaHCO 3 solution (10 ml), the organic layer was separated, washed with water (3×10 ml), dried over sodium sulfate, filtered and evaporated. The residue was distilled under reduced pressure (bp 13 =63-64° C.) to yield 2.2 g (13.7 mmol, 48%) of 4 as a colorless oil.
R f 0.64 (ethyl acetate/toluene 2:8);
1 H NMR (CDCl 3 ) δ 1.17 (s, 9H, tBu), 1.43 (t, 1H, SH, J=8.5 Hz), 2.66-2.75 (m, 2H, SCH 2 CH 2 ), 4.14 (t, 2H, CH 2 CH 2 O)
EXAMPLE 16
General Procedure For the Preparation of the Phosphorodithiolates S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxyadenosin-5′-yl phosphorodithiolate and S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxy-2′,3′-didehydrothymidin-5′-yl phosphorodithiolate
The appropriate nucleoside (0.5 mmol) was dissolved either in a mixture of DMF and dichloromethane (d4T, 1:3, 6 ml) or in DMF (ddA, 6 ml) by warming the solution at 50° C. After cooling to room temperature, the solution was stirred for 2 h over 3 Å molecular sieve (0.5 g). Tris(pyrrolidino)phosphine 1 2 (120 mg, 0.55 mmol) was added, followed by 1H-tetrazole in seven aliquots (7×50 μl of 0.5M tetrazole in acetonitrile, 0.175 mmol) at 3 min intervals. After stirring at room temperature for 15 min, 1H-tetrazole (5.2 ml 0.5M tetrazole in acetonitrile, 2.60 mmol) was added, immediately followed by the addition of the thiol 4 (243 mg, 1.5 mmol). The reaction mixture was stirred at room temperature for 45 min and then cooled to −40° C. tert-Butyl-hydroperoxide (360 μl, 3M in toluene) was added and the reaction mixture allowed to warm to room temperature over 45 min. The reaction mixture was concentrated under reduced pressure to approximately 2 ml and diluted with dichloromethane (10 ml). The excess of oxidant was destroyed by the addition of Na 2 S 2 O 3 (10%, 5 ml). The organic phase was separated and the aqueous phase extracted twice with dichloromethane (2×10 ml). The combined organic layers were successively washed with brine (10 ml) and water (10 ml). The organic layer was dried with sodium sulfate, filtered and concentrated to dryness under reduced pressure. Column chromatography of the residue on silica gel afforded the title compounds.
EXAMPLE 16A
S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxyadenosin-5′-yl Phosphorodithiolate
85 mg, 0.14 mmol, 28% after chromatography [eluent, stepwise gradient of methanol (3→5%) in dichloromethane].
R f 0.30 (methanol/dichloromethane 1:9);
1 H NMR (CDCl 3 ) δ 1.20 (s, 18H, tBu), 2.19-2.28 (m, 2H, 3′-H, 3″-H), 2.48-2.68 (m, 2H, 2′-H, 2″-H), 3.07-3.20 (m, 4H, SCH 2 CH 2 ), 4.29 (t, 4H, CH 2 CH 2 O, J=6.4 Hz), 4.30-4.48 (m, 3H, 4′-H, 5′-H, 5″-H), 5.3 (bs, 2H, NH 2 ), 6.31 (q, 1H, 1′-H, J=3.9, 6.5 Hz), 8.07, 8.35 (2s, 2H, 2-H, 8-H);
13 C NMR (CDCl 3 ) δ 26.03 (C-3′), 27.05 (C(CH 3 ) 3 ), 30.42, 30.45 (2d, SCH 2 CH 2 , J p-c 14 Hz), 32.16 (C-2′), 38.72 (C(CH 3 ) 3 ), 62.56, 62.58 (2d, OCH 2 CH 2 , J p-c 5 Hz), 67.93 (d, C-5′, J p-c 8 Hz), 79.20 (d, C-4′, J p-c 8 Hz), 85.51 (C-1′), 120.02 (C-5), 138.71 (C-8), 149.23 (C-4), 152.82 (C-2), 155.48 (C-6), 177.95 (C═O);
31 P NMR (CDCl 3 ) δ 57.09 (s);
FAB MS (>0, G═T) m-e 604[M +H] + ;
FAB MS (<0, G-T) m-e 602 [M−H]; 474 [OPS (SR) (OddA)]; 385 [OPO(SR) 2 ];
UV (ethanol 95) λ max 259 nm (ε 14900);
HPLC t R 29.5 min.
EXAMPLE 16B
S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxy-2′,3′-didehydrothymidin-5′ -yl phosphorodithiolate
98 mg, 0.17 mmol, 33% after column chromatography (eluent ethylacetate/dichloromethane 3:7);
R f 0.28 (dichloromethane/ethyl acetate 4:6);
1 H NMR (CDCl 3 ) δ 1.19, 1.20 (2s, 18H, tBu), 1.94 (d, 3H, thymine-CH 3 , J=1.2 Hz), 3.09-3.21 (m, 4H, SCH 2 CH 2 ), 4.24-4.34 (m, 5H, CH 2 CH 2 O, 5′-H), 4.37-4.48 (m, 1H, 5″-H), 5.03-4.29 (m, 1H, 4′-H), 5.91-5.93 (m, 1H, 2′-H), 6.34-6.36 (m, 1H, 3′-H), 7.01-7.03 (m, 1H, 1′-H), 7.20 (d, 1H, 6-H, J=1.1 Hz), 8.80 (bs, 1H, NH);
13 C NMR (CDCl 3 ) δ 12.56 (thymine-CH 3 ), 27.08 (C(CH 3 ) 3 ), 30.51, 30.54 (2d, SCH 2 CH 2 , J p-c 40 Hz), 38.76 (C(CH 3 ) 3 ), 62.59, 62.63 (2d, OCH 2 CH 2 , J p-c 13 Hz), 67.15 (d, C-5′, J p-c 8 Hz), 84.15 (d, C-4′, J p-c 9 Hz), 89.58 (C-1′), 111.43 (C-5), 127.84 (C-2′), 132.86 (C-3′), 135.48 (C-6), 150.69 (C-2), 163.55 (C-4), 177.94 (C═O);
31 P NMR (CDCl 3 ) δ 57.29 (s)
FAB MS (>0, G-T) m-e 1185 [2M +H] + ;
FAB MS (<0, G-T) m-e 1183 [2M−H]; 591 [M−H]; 463 [OPS(SR)(Od4T)]; 385 [OPO(SR) 2 ];
UV (ethanol 95) λ max 264 nm (ε 7250);
Anal. Calcd for C 24 H 37 N 2 O 9 PS 2 : C, 48.63; H, 6.29; N, 4.73; S, 10.82; Found: C, 48.65; H, 6.38; N, 4.73; S, 10.97.
HPLC t R 29.6 min.
EXAMPLE 17
Stability Studies of Isosteric S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxyadenosin-5′-yl phosphorodithiolate and O-(2′,3′-dideoxyadenosin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate
Certain kinetic studies comparing the compound of example 16A, i.e., S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxyadenosin-5′-yl phosphorodithiolate, also designated as iso[Bis(SATE)ddA] and its isosteric compound of Example 9, i.e., O-(2′,3′-dideoxyadenosin-5′-yl)-O,O′-bis(S-acetyl-2-thioethyl)phosphate, also designated as [Bis(SATE)ddAMP] were effected. The kinetic were studies were performed in culture medium (RPMI containing 10% heat-inactivated fetal calf serum) in order to evaluate the stability of the pronucleotides in the extracellular medium used for antiviral evaluation in cell culture systems, and in total cell extracts that mimic the behavior of the compounds inside cells. The “on-line ISPR cleaning” HPLC method of Lefebvre et al., J. Med. Chem., 38, 3941-3950, 1995, were used for the studies. The products resulting from the decomposition were characterized by co-injection with authentic samples and/or by coupled HPLC/Mass Spectroscopy. The kinetics of transformation of the two isomeric pronucleotides strongly differed according to the medium. In culture medium the first iso-SATE group was cleaved in 38.5 hr whereas the first SATE group was cleaved in 165 hr. The second iso-SATE group was cleaved in 5.8 hr whereas the second SATE group was cleaved in 46 hr. In total cell extracts, the first iso-SATE group was cleaved in 5.3 hr whereas the SATE group was cleaved in 1 hr.
EXAMPLE 18
Decomposition Pathway of S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxyadenosin-5′-yl Phosphorodithiolate, i.e. iso[Bis(SATE)ddA], and S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxy-2′,3′-didehydrothymidin-5′-yl Phosphorodithiolate, i.e. iso [Bis(SATE)d4T]
The proposed decomposition pathway for the compounds of Example 16a and 16b, ie., S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxyadenosin-5′-yl phosphorodithiolate and S,S′-bis(O-pivaloyl-2-oxyethyl)O-2′,3′-dideoxy-2′,3′-didehydrothymidin-5′-yl phosphorodithiolate, also designated as iso[Bis(SATE)ddA] and iso[Bis(SATE)d4T] is shown in FIG. 9 . This pathway was studied in conjunction with the kinetic studies of Example 17. While we do not wish to be bound by theory, based upon these results it is presently believed that the decomposition pathway for the iso-SATE pronucleotide involves:
(a) carboxyesterase-mediated cleavage of the ester function leading to (A);
(b) nucleophilic attack of the liberated hydroxyl function on the phosphorus atom, forming the five-covalent intermediate (B);
(c) conversion of the intermediate (B) into the 2-mercaptoethyl phosphorotriester (C);
(d) spontaneous elimination of episulfide, leading to the corresponding phosphorothiolate diester (D); and
(e) hydrolysis of the phosphorothiolate diester (D) into the corresponding 5′-monophosphate by a similar mechanism (a-b-c-d) or following the action of phosphodiesterases. Additionally, the hydrolysis of the iso-SATE pronucleotide may involve a direct nucleophilic attack on the phosphorus atom, leading directly to the phosphothiolate diester (D). Again while we do not wish to be bound by theory, we believe this might explain the faster decomposition of the iso-SATE pronucleotide compound to that of the SATE pronucleotide compound in culture medium.
EXAMPLE 19
Anti-HIV activity of Mononucleoside S,S′-bis(O-pivaloyl-2-oxyethyl)phosphorodithiolates
The iso-SATE pronucleotides of Examples 16A and 16B were evaluated for their inhibitory effects on the replication of HIV-1 in CEM-SS and in thymidine-kinase deficient cell lines (CEM/TD). For comparison, the parent nucleosides ddA and d4T, and the corresponding bis(SATE) phosphotriesters bis(tBuSATE)ddAMP (the compound of Example 9) and bis(tBuSATE)d4TMP, were evaluated in the same experiments. The results are shown in FIG. 10 . In the two cell culture systems, the anti-HIV-1 activities of the tBu(iso)SATE pronucleotide were similar to those of their corresponding tBu(SATE) pronucleotides, both types of isomeric pronucleotides being more potent inhibitors than the parent compound ddA. The d4T derivative showed high inhibitory effects in thymidine-deficient (TK) CEM cells while, as expected, the d4T is weakly active in this cell line. This data clearly demonstrates that the isoSATE pronucleotides that were evaluated could act as efficient prodrugs forms of the 5′-monophosphates, circumventing the first activation step by cytosolic kinases. | Compounds of formula RS—P(═O)(QR)—Nu where: R is a radical —(CH 2 )n—W—X; X is a radical —C(═Z) (Y) or —S—U; Z is O or S; W is O or S; Q is O or S; Y and U are an alkyl, aryl or saccharide radical which is optionally substituted with, for example, an OH, SH or NH group; n is equal to 1 to 4, preferably 1 or 2; and Nu is a radical consisting of a residue of a biologically active compound or the dephosphorylated residue of a compound which is biologically active when it bears a phosphate or phosphonate group. | 2 |
BACKGROUND OF THE INVENTION
This invention relates in general to apparatus for pumping a liquid, and relates in particular to apparatus for metering a predetermined quantity of a first liquid for mixture with a second liquid.
There are many applications where it is necessary to meter and intermix two liquids or other fluids in some certain predetermined proportion. In the handling and dispensing of beverages, for example, a predetermined quantity of one ingredient such as a beverage concentrate must be intermixed with another ingredient to provide a beverage suitable for consumption. The proportion of concentrate mixed with the carrier or other liquid is usually a fixed proportion in order to maintain the desired taste and other characteristics of the resulting mixed beverage, and even a relatively small departure from the intended proportion of concentrate may produce a significant and easily-detectable departure from the desired taste or appearance of the mixed beverage. For that reason along with others, the ability to provide a consistent and repeatable proportionate mixture of two liquids is most important in the beverage industry. Numerous other instances of commercial or industrial application for metering apparatus will be apparent to those skilled in the art.
Although various types of pumping or dispensing apparatus have been proposed, the liquid metering apparatus of the prior art has proven less than satisfactory for many applications. A simple syphon metering system, depending on the flow of one liquid to provide a reduced pressure for pumping a quantity of a second liquid, makes metering accuracy dependent on velocity and rate of flow, viscosity of the liquids, and on other variables, and has proven difficult to maintain a desired matering proportion with necessary accuracy. While positive-displacement metering apparatus is not new by itself, such apparatus tends to be relatively complex and/or expensive to construct and maintain. Furthermore, positive-displacement liquid pumping apparatus of the prior art generally delivers a fixed volume of pumped liquid with each stroke or cycle of a motor or other driving device, and the volume of pumped liquid can be adjusted, if at all, only with some difficulty or expense.
SUMMARY OF INVENTION
Stated in general terms, the liquid metering apparatus of the present invention includes a motor which is operated in response to the positive displacement of a certain amount of a first or "operating" liquid, and which delivers a fixed yet selectably-variable amount of a second or "working" liquid for each operating cycle of the motor. Stated somewhat more specifically, liquid metering apparatus according to the present invention includes a pump which operates in response to delivery of a certain volume of an operating liquid, and which displaces a selectably variable volume of working liquid for each volume of operating liquid delivered.
The present liquid metering apparatus includes a motor which undergoes an operating cycle in response to delivery of a certain positive volume of operating liquid. Each operation of the motor causes a pump operating member to engage a pumping piston having an effectively variable stroke, so that the volume of working liquid pumped for each operation of the pump operating member is easily adjusted.
Accordingly, it is an object of the present invention to provide an improved liquid metering apparatus.
It is another object of the present invention to provide liquid metering apparatus for delivering a selectably fixed volume of one fluid in response to delivery of a certain volume of another fluid.
It is yet another object of the present invention to provide liquid metering apparatus for delivering a selectably variable volume of working liquid in response to delivery of a fixed volume of operating liquid.
Other objects and advantages of the present invention will become more readily apparent from the following description of disclosed embodiments thereof.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows a schematic view of metering apparatus according to disclosed embodiments of the present invention.
FIG. 2 is a section view showing a first disclosed embodiment of metering apparatus according to the present invention.
FIG. 3 is a fragmentary section view of the metering apparatus in FIG. 2, showing the shuttle valve in an alternative position.
FIG. 4 is a section view showing an alternative embodiment of metering apparatus according to the present invention.
FIG. 5 is a section view showing the pumping piston of the embodiment in FIG. 4.
FIG. 6 is a section view showing the sleeve shuttle valve of the embodiment in FIG. 4.
DESCRIPTION OF PREFERRED EMBODIMENTS
Turning first to the overall schematic diagram shown in FIG. 1, the metering apparatus according to the present invention is seen to include a metering pump indicated generally at 10, and connected to receive both a source of operating liquid and a supply of working liquid. The operating liquid is identified as water in FIG. 1, and is supplied to the metering pump at the inlet line 11. The working liquid is supplied to the metering pump through the line 15 from a suitable source of pumped liquid. It will be apparent to those skilled in the art, however, that the identification herein of specific liquids is only by way of example, and without limitation as to the particular kind or nature of liquids with which the present metering apparatus can be used.
Each operating cycle of the metering pump 10 causes the displacement of a certain amount of operating liquid such as water, as becomes more apparent below, and the displaced operating liquid exits the metering pump through the line 12 leading to the mixing chamber M. Each amount of working liquid pumped in response to an operating cycle of the metering pump 10 is also directed to the mixing chamber M, by way of the line 13. The two liquids are intermixed in the mixing chamber, and become the pumped mixture delivered along the line 14 for utilization elsewhere. The mixing chamber M can be any chamber or passage that commingles the two liquids passing through the metering pump 10; as is seen below with respect to the embodiment shown in FIG. 4, the mixing chamber may be integral with the metering pump.
Turning now to FIG. 2, there is shown a specific embodiment of metering pump 10 comprising a fluid-operated motor portion 16 and a positive-displacement pump portion 17. The motor portion 16 and the pump portion 17 are shown constructed in separate and separable components for ease of assembly and maintenance, with the two components being interconnected by way of the removable fasteners 18a and 18b.
Turning first to the motor portion 16, a motor housing 19 is provided having an internal cylindrical chamber 20 defining a pump motor cylinder within which the motor piston 21 is received for reciprocation. A suitable fluid seal such as the O-ring 22 is disposed about the periphery of the piston 21, to provide a fluid-tight wiping seal as the motor piston reciprocates within the cylinder 20. The region 23 to the left of the motor piston 21, as viewed in FIG. 2, receives operating liquid to act against the piston, as is pointed out later, while the region 24 to the right of the motor piston receives neither operating liquid nor working liquid and is normally vented to atmosphere.
The motor housing 19 extends a distance to the left of the cylinder 20 to define the valve housing 28, which as illustrated in FIG. 1 may preferably be formed integrally with the remainder of the housing 19 so as to minimize liquid sealing requirements. The valve housing 28 has an internal bore 29 coaxial with the cylinder 20, and of reduced diameter relative to the cylinder. Received within the bore 29 is a cylindrical member 30 comprising a shuttle valve for the operating liquid. The shuttle valve 30 is dimensioned to be freely reciprocable within the bore 29, and the shuttle valve has a pair of adjoining and intersecting indentations 31a and 31b formed on its exterior surface. The indentations 31a and 31b, which may advantageously be provided by a pair of partially-overlapping annular grooves formed about the exterior periphery of the shuttle valve 30, interact with a detent ball 32, urged inwardly against the shuttle valve by the detent spring 33, so as to define and limit two longitudinally-displaced positions which the shuttle valve may occupy within the bore 29. The first or left position of the shuttle valve 30 is shown in FIG. 2, and the second or right position of the shuttle valve is shown in FIG. 3.
An inlet port 37 and an outlet port 38 extend through the valve housing 28 for selective communication with the bore 29. The inlet and outlet ports are spaced apart from each other, and are longitudinally located relative to the two possible longitudinal positions of the shuttle valve 30, so that only one of the two ports is unblocked at either position of the shuttle valve. Thus, the inlet port 37 is unblocked and the outlet port 38 is blocked when the shuttle valve 30 is in the first position shown in FIG. 2; the opposite status of the inlet and outlet ports maintains when the shuttle valve moves to its second position, shown in FIG. 3.
Extending through the interior of the shuttle valve 30 is a hollow passage 41 concentric with the bore 29, and a valve operating rod 42 extends through the passage 41. The valve operating rod 42 is secured to the motor piston 21 for reciprocation in response to piston movement, but the operating rod does not engage the shuttle valve 30. The diameter of the operating rod 42, relative to the diameter of the passage 41 within the shuttle valve, is selected so that a fluid flow channel is defined between opposite ends of the shuttle valve, for a purpose described below.
One end 43 of the operating rod 42 extends a distance to the left of the shuttle valve 30, and a first valve operating compression spring 44 is retained about the operating rod between the end 43 and the left side of the shuttle valve. A second valve operating spring 45 is disposed about the operating rod 42, between the right end of the shuttle valve 30 and the boss 46 extending a distance axially outwardly from the motor piston 21.
The operating rod 42 extends a distance to the right of the motor piston 21, and terminates with a pump operating rod 47 extending into the pump portion 17 of the metering pump 10, described below. A return spring 48 surrounds the operating rod to the right of the motor piston 21, and biases the motor piston to the left as viewed in FIG. 2.
The pump portion 17 has an elongated pump body 50 which, in external configuration, may match the cross-sectional shape of the motor housing 19. One end of the pump body 50 may have an outside diameter of reduced dimension, as shown at 51, to accommodate the open end 52 of the motor housing 19 beyond the region 24 of the motor cylinder 20. An O-ring seal 53 may be fitted between the open end 52 of the motor housing and the region 51 of the pump body 50, although as previously stated neither operating fluid nor working fluid should normally be present within the region 24.
Extending longitudinally through the pump body 50 is a pump bore 55 coaxial with the motor cylinder 20 and with the pump operating rod 47, a portion of which extends a distance into the pump bore. One end of the motor piston return spring 48 is seated within a counterbore 56 of the pump bore 55, confronting the region 24 of the pump cylinder, and a radial bore 57 extends from the counterbore outwardly to the exterior of the pump body 50 to provide an air vent to the region 24 of the motor cylinder 20.
The portion of pump operating rod 47 extending within the pump bore 55 is sized to permit free reciprocation of the operating rod within the pump bore, as the motor piston 21 is driven for reciprocation. A floating pump piston 60 is fitted within the pump bore 55, and is equipped with an O-ring seal engaging the wall of the pump bore. That portion of the pump bore 55 extending from the right of the floating pump piston 60 comprises the pump chamber 64, the right end of which is defined by the end 62 of the piston stroke adjuster 63 which is screwed into a threaded receptacle 65, coaxial with the pump bore 55, formed in the end 66 of the pump body 50. An O-ring seal 67 is provided at the end 62 of the piston stroke adjuster to prevent leakage of working fluid from the pump chamber 64. A compression coil spring 61 within the pump chamber 64 extends between the end 62 of the piston stroke adjuster 63 and the facing end of the floating pump piston 60 at the other end of the pump chamber, tending to bias the floating pump piston toward the pump operating rod 47.
The line 15 supplying pumped liquid to the metering pump 10 communicates with the pump chamber 64 by means of the inlet port 70. A ball check valve 71 contained within the pump body 50, between the inlet port 70 and the line 15, prevents the pumped working liquid in the pump chamber 64 from returning to the line 15.
The output line 13 for the pumped working liquid similarly communicates with the pump chamber 64 by way of a port 72, and a second ball check valve 73 located within the pump body 50 prevents the pumped working liquid from returning to the pump chamber from the output line 13.
The operation of the metering pump embodiment shown in FIGS. 2 and 3 is now described. It is assumed that the shuttle valve 30 and the motor piston 21 are both in their respective left-most positions, that a source of pressurized working liquid is connected to the input port 37 of the motor, and that the inlet line 15 of the pump portion 17 is connected to a suitable supply of working liquid to be pumped. As the operating liquid enters the port 37 and flows through the bore 29 to enter the cylinder region 23, the operating liquid exerts a force moving the motor piston 21 to the right, compressing the return spring 48. The shuttle valve 30 remains in its first position, shown in FIG. 2. The rightward movement of the motor piston 21 carries with it the operating rod 42, causing the first valve spring 44 to compress and exert an increasing force against the left end of the shuttle valve 30 and correspondingly reducing the force of the second valve spring 45 against the right end of the shuttle valve.
When the force exerted on the shuttle valve by the first valve spring 44 exceeds the retaining force of the detent ball 32 against the cam surface 31b, the shuttle valve will suddenly shift to its second position shown in FIG. 3. At that time, the shuttle valve blocks the inlet port 37 and opens the previously-blocked outlet port 38, thus permitting the operating liquid in the region 23 of the motor cylinder 20 to drain along a path including the bore 29, the annular passage between the operating rod 42 and the interior passage 41 of the shuttle valve 30, and the outlet port 38 itself. The motor piston 21 is thus urged leftwardly by the piston return spring 48, causing the piston and the operating rod 42 to return to their initial position while forcing operating liquid out of the cylinder 20.
The leftward or return movement of the motor piston 21, under influence of the piston return spring 48, continues until the second valve operating spring 45 exerts sufficient leftward force against the shuttle valve 30 to return the shuttle valve to its initial position shown in FIG. 2. When that occurs, the operating fluid inlet port 37 is reopened and the motor operating cycle commences to repeat itself.
As the operating rod 47 moves rightwardly during the forward movement of the motor piston 21, the floating pump piston 60 is contacted and moved rightwardly, thereby compressing the spring 61 and reducing the volume of the pump chamber 64. Any working liquid previously in the pump chamber 64 is thereby forced past the check valve 73 and out along the line 13. When the pump operating rod 47 is withdrawn leftwardly by return movement of the motor piston 21, the spring 61 forces the floating pump piston 60 leftwardly to an extent determined by the fully-extended position of the spring, and by the adjustment position of the piston stroke adjuster 63. This spring-induced leftward or return movement of the floating pump piston 60 enlarges the volume of the pump chamber 64, thereby drawing a quantity of working liquid into the pump chamber through the check valve 71 and the inlet port 15. That quantity of working liquid drawn into the pump chamber 64 by the return stroke of the floating pump piston 60 will be ejected from the pump chamber 64 through the line 13, by the next forward stroke of the operating rod 47.
It will be appreciated that the length of the pump chamber 64 swept by the floating pump piston 60 in response to each complete operating cycle of the pump motor 16, and thus the volume of working liquid pumped by each such cycle, is determined by the position of the piston stroke adjuster 63. Moving the end 62 of the piston stroke adjuster further into the pump bore 55 correspondingly moves the floating pump piston 60 closer to the free end of the pump operating rod 47 in its leftmost position, thereby reducing the amount of free or lost motion in bore 55 which the pump operating rod must undergo in its forward stroke before contacting the floating pump piston. The volume of the pump chamber 64 swept by the floating pump piston in response to each stroke of the pump operating rod 47, and thus the volume of working liquid pumped in response to each such stroke, is thus increased. Similarly, rightward movement of the piston stroke adjuster increases the lost-motion space in bore 55 between the pump operating rod 47 and the floating pump piston 60, thereby decreasing the extent of pump piston movement and the volume of pumped working liquid pumped in response to each stroke of the pump operating rod.
It will thus be seen that each complete operating cycle of the motor portion 16 is caused by a certain fixed volume of operating liquid entering the motor, and then passing via line 12 to the mixing chamber M. For each such operating cycle of the motor 16, the mixing chamber M receives a pumped volume of working liquid which remains fixed for each operating cycle, but which is readily adjustable. The proportion of working liquid to operating liquid in the pumped mixture, flowing in the output line 14 from the mixing chamber M, thus is unchanged by flucuations in pressure, flow rate or other parameters of the operating liquid supplied to the motor portion 16, and is determined solely by setting the piston stroke adjuster 63 to provide the desired proportion.
Turning next to FIGS. 4-6, a second embodiment of metering pump is disclosed with primed reference numerals used to designate elements corresponding to like elements in the previously-described embodiment. The metering pump 10' includes both a motor portion 16' and a pump portion 17' whose construction and operation are substantially comparable to the preceding embodiment. Moreover, the pumped working liquid is mixed with the operating liquid internally within the metering pump 10', so that no separate mixing chamber M is required for the metering pump shown in FIGS. 4-6.
The metering pump 10' is assembled with two major external components, a cylinder 78 open at one end and a housing 79 also open at one end and telescopically received a distance within the open end of the cylinder. The piston 21' fits within the cylinder 78 for reciprocal movement between the open end of the housing 79 and the closed end 80 of the cylinder; the motor piston thus divides the interior of the cylinder 78 into a region 23' for receiving operating liquid as described below, and a region 24' which is vented to atmosphere through the vent bore 57' formed in the outwardly-extended central portion 81 of the cylinder.
The motor piston 21' is shown in detail in FIG. 5, and includes an operating rod 82 extending axially outwardly from the left face of the piston. The operating rod 82 terminates at the free end 83, and an extension to the left of the free end constitutes the pump operating rod 47'. An annular groove 86 extends around the periphery of the operating rod 82, spaced a short distance to the right of the free end 83.
A coaxial bore 87 is formed in the right surface 88 of the piston 21', and extends a distance inwardly into the operating rod 82. This bore 87, as seen in FIG. 4, accommodates one end of the piston return spring 48', the other end of which is positioned in a confronting recess within the closed end 81 of the cylinder 78. The interior of the operating rod 82 includes a coaxial second bore 89 of reduced diameter from the bore 87, and a coaxial third bore 90 of reduced diameter relative to the second bore. The interface 91 between the second and third bores is formed with a concave shape to provide a seat for the ball check valve 92, FIG. 4. A fourth coaxial bore 93 communicates with the third bore 90 through the remaining length of the operating rod 82, and thence through the interior of the pump operating rod 47' to communicate with the free end 94 of the pump operating rod.
Extending leftwardly from the closed end 98 of the housing 79 is an extension 99 containing a longitudinal bore 100 coaxial with the hollow interior of the cylinder 78. The bore 100 has a portion of somewhat enlarge diameter to constitute the pump chamber 64', communicating with the hollow interior 101 of the housing 79. The pump operating rod 47' of the motor piston 21', in assembly as seen in FIG. 4, extends a distance into the pump chamber 64', and an O-ring seal 102 surrounding the exterior of the pump operating rod provides a liquid-tight seal between the pump chamber 64' and the interior 101 of the housing 79.
Received within the bore 100 of the extension 99 is the floating pump piston 60', having a free end confronting the end 94 of the pump operating rod 47' within the pump chamber 64'. The other end of the floating pump piston 60' contacts a compression spring 61', located in the bore 100 between the floating pump piston and the piston stroke adjuster 63' screwed into a threaded opening in the end 103 of the extension 99.
The input line 11' for the motor operating liquid is attached to the exterior of the cylinder 78, in fluid communication with an annular channel 106 formed about the interior of the cylinder. The channel 106 is aligned with fluid flow ports collectively designated 107 in the housing 79, to allow operating liquid to flow from the line 11' into the cylinder region 23'. The fluid flow ports may be provided by a plurality of radial holes drilled through the wall of the housing 79 at equidistant circumferential spacing about the housing. Another annular channel 108 is formed in the interior of the cylinder 78, longitudinally spaced from the channel 106 and toward the open end of the cylinder. A corresponding series of fluid flow ports 109 is formed in the wall of the housing 79 in alignment with the channel 108, and the ports 109 may likewise be provided by a number of radial holes bored in the housing wall at equidistance circumferential spacing.
Slidably received within the interior of the housing 79, in close proximity to the inside surface 112 thereof, is the shuttle valve 30' shown in assembly in FIG. 4, and shown separately in FIG. 6. The shuttle valve 30', like its counterpart 30 in the preceding embodiment, is maintained in either of two positions by the detent ball 32', and is longitudinally dimensioned to block fluid flow either from the ports 107 or 109, depending on the position of the shuttle valve. The detent ball 32' is spring-biased to engage either of the cam surfaces 311' or 31b' circumferentially formed about the exterior of the shuttle valve.
A coaxial bore 113 extends through the shuttle valve 30' to accommodate the operating rod 82 of the motor piston 21', and also to define the annular fluid channel 114 (FIG. 4) surrounding the operating rod. The bore 113 through the shuttle valve 30' is counterbored at each end 115a and 115b, and a pair of valve operating springs 44' and 45' extend longitudinally outwardly in opposite directions from the two counterbores. The opposite end of the valve spring 44' engages a spring retainer 116, located adjacent the free end 83 of the operating rod 82 and held on the operating rod by the snap ring 117 received in the annular groove 86 of the operating rod. The other valve spring 45' presses against the confronting face of the piston 21', and is located about the region of enlarged diameter 118 forming a boss joining the operating rod 82 with the piston face.
The ball check valve 92 is retained within the bore 89 of the operating rod 82 by the plug 120, having a stem substantially narrower than the diameter of the second bore. The plug 120 terminates in a head engaging the inner end of bore 87, and there held in place by the piston return spring 48'. The plug 120 locates the ball check valve 92 within the second bore 89, but does not urge that ball against the valve seat 91. Radial fluid passage 121, which may comprise a number of radial holes bored through the operating rod 82, provides a fluid flow passage between the second bore 89 and the channel 114 surrounding the operating rod.
The working liquid to be pumped by the metering pump 10' is supplied through line 15', including a ball check valve 71' to prevent the return of working liquid from the pump chamber 64' to the line 15'. The outlet line 14' communicates with the annular channel 108 formed in the cylinder housing 78.
The operation of the metering pump embodiment shown in FIG. 4 is now discussed, and it will be seen that the operating is substantially similar in many respects to that of the preceding embodiment. Although the shuttle valve 30' is depicted in FIG. 4 midway between its two alternative positions, it is assumed the shuttle valve is initially to the left position allowing pressurized operating liquid to flow through the line 11' and the ports 107 to enter the cylinder region 23', thereby moving the piston 21' to the right against the return force of the piston return spring 48'. The pump operating rod 47' also moves to the right at this time, enlarging the effective volume of the pump chamber 64' and thereby drawing a quantity of working liquid into the pump chamber through the line 15' and the check valve 71'. Check valve 92 is held closed against seat 91 by differential pressure at this time.
Rightward movement of the motor piston 21' continues, compressing the valve operating spring 44' until the force of that spring against the shuttle valve 30' overcomes the retaining force of the detent 32' and moves the shuttle valve to its right-most position. The flow of operating liquid to the piston 21' is then blocked and the ports 109 in the housing 79 are unblocked, allowing the operating liquid in the cylinder region 23' to flow through the annular channel 114 and out of the ports 109 as the piston return spring 48' moves the piston towards its left-most position. Movement of the pump operating rod 47' into the pump chamber 64' causes the working liquid previously drawn into that chamber to flow through the bore 93 in the pump operating rod, past the check valve 92, and through the passages 121 to intermix with the flow of operating liquid passing through channel 114 toward the ports 109 and the exit line 14'. Accordingly, the return movement of the piston 21' causes a predetermined quantity of working liquid, previously pumped into the pump chamber 64', to become mixed with the fixed volume of operating liquid required to move the motor piston in a cycle of operation. The position of the floating pump piston 60', controlled by the piston stroke adjuster 63', determines the volume of working liquid to be pumped and intermixed with the operating liquid, for each complete cycle of the metering pump 10'.
It will be understood that the foregoing relates only to preferred embodiments of the present invention and that numerous changes and modifications may be made therein without departing from the spirit and the scope of the invention as defined in the following claims. | Metering apparatus combining a motor operated by a first liquid, and a pump driven by the motor to meter a selectably variable volume of a second liquid. The motor has a liquid-operated piston and a shuttle valve to control the flow of operating liquid to the piston. The piston drives a pump actuating rod which, in turn, engages a floating pump piston. The effective stroke of the floating pump piston can be varied to adjust the volume of liquid pumped in response to each cycle of the motor. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to breast imaging and in particular to a computerized simulator for training and testing of individuals performing analysis of screening and diagnostic breast images.
[0002] Breast cancer is the second leading cause of death in women and the most common cancer in women in the United States. Screening mammography is the only current exam that increases the detection of early clinically occult breast cancers in women of average risk.
[0003] Mammography uses low energy x-rays to provide a radiographic image of breast tissue typically under mild compression. The radiographic image can reveal masses, asymmetries, architectural distortion or microcalcifications associated with breast cancer when reviewed by a trained professional.
[0004] The results of mammographic imaging are typically provided in the form of a prose clinical report describing features of the mammogram and clinical impressions. Included with the report will often be a ranking expressed in terms of a BI-RADS (Breast Imaging-Reporting and Data System) assessment category ranging from 0-6. In the BI-RADS ranking, categories 1 and 2 are normal or benign, category 3 is probably benign, categories 4 and 5 indicate a suspicion or likelihood of malignancy, and category 6 reflects imaging of a patient with a known diagnosis of breast cancer prior to definitive treatment. Normally a category 0 assessment during a screening mammogram will result in a recall for additional imaging.
[0005] The interpretation of mammograms is a complex process requiring a significant level of experience-honed judgment. For this reason, training in the interpretation of mammograms is normally done by parallel assessments of current cases by an experienced clinician working together in a one-on-one session with the individual to be trained. Although such training is extremely valuable in obtaining competency, the need for and format of one-on-one training sessions of this type understandably limits the opportunity for such training,
SUMMARY OF THE INVENTION
[0006] The present inventor has recognized that valuable ancillary training can be obtained on an automated basis by using a set of mammographic images that have been pre-characterized by an expert. For this purpose, much of the complexity of a clinical evaluation can be usefully simplified to a trainee's assessment of the BI-RADS or similar categories reflecting whether a recall for additional imaging would be required. A similar simplification may be used to obtain a more nuanced assessment of the trainee's understanding by soliciting a prediction of the likely BI-RADS results of that follow-up imaging. Unlike in an actual screening where an expert does not know the outcome of subsequent screening or a biopsy, the expert's characterization of the mammographic images in the simulation may optionally be informed by after-the-fact knowledge about the case (e.g. subsequent screening and/or biopsy) to provide an extremely high level of effective expertise.
[0007] Specifically, the present invention provides a simulator for breast imaging (mammograms, ultrasound, etc.) including a medical grade computer display and a data input device communicating with an electronic computer. The computer memory may hold a data structure having multiple records linking breast imaging studies to expert recall instructions, the latter indicating whether a patient associated with each mammographic image should be recalled for additional imaging based on the mammographic image. During operation, the computer executes a stored program to successively read the records of the data structure and, for each record, to display at least one mammographic image of the record and receive input through the trainee input device indicating a trainee recommended recall instruction. After reviewing of the records is complete, the program outputs a report indicating divergence between the trainee recommended recall instructions and the expert recall instructions.
[0008] It is thus a feature of at least one embodiment of the invention to provide an automatable method of training and assessing the interpretation of mammographic images. By identifying quantitative, computer-readable features of the diagnosis (for example BI-RADS categories) meaningful automated evaluation can be performed while maintaining a realistic clinical setting.
[0009] The records of the data structure may provide expert recall instructions that are predominantly instructions for no recall.
[0010] It is thus a feature of at least one embodiment of the invention to provide a simulation experience that is roughly analogous to real world practice in which most screenings do not result in a recall.
[0011] Nevertheless, the records of the data structure may provide expert recall instructions instructing recall of the patient greater than a normal expected percentage of five to twelve percent. For example, the expert recall instructions may instruct recall of the patient for greater than 20 percent and as high as 25 percent of the records, to enhance the learning experience and provide appropriate feedback where user has difficulty.
[0012] It is thus a feature of at least one embodiment of the invention to provide a more engaging and better training experience by increasing the recall rate above that found in a typical population.
[0013] The after-recall assessments may be encoded as numeric BI-RAD scores.
[0014] It is thus a feature of at least one embodiment of the invention to make use of a familiar and well-established scoring technique for automatic skill comparison and assessment.
[0015] The simulator may further receive input through the data input device indicating a trainee predicted “after-recall” assessment predicting an assessment after the patient of the record is recalled for further imaging and analysis and the records of the data structure may further provide an expert “after-recall” assessment indicating the ultimate assessment of the patient. In this case, the output report may indicate a divergence between trainee predicted “after-recall” assessment and expert “after-recall” assessment. This prediction may further include a numeric likelihood of biopsy and a type of biopsy.
[0016] It is thus a feature of at least one embodiment of the invention to derive greater insight into the understanding of the trainee beyond the readily quantified recall recommendation, by having the trainee classify the findings, predict the likely results of that recall and optionally whether a biopsy will be required and the type of biopsy. As before, this prediction may be captured by machine-readable numeric scores.
[0017] The simulator may further receive input through the data input device indicating a trainee-determined location and description of the suspicious imaging finding on the mammographic image of each record and the records of the data structure may provide expert-determined location of suspicious imaging findings (masses, calcifications, etc) on the mammographic image of each record. In this case, the output report may indicate a divergence between trainee-determined locations of suspicious imaging finding and expert-determined locations of suspicious imaging findings informed by positional error between the trainee-determined location of suspicious imaging finding and the expert-determined location of suspicious imaging findings.
[0018] It is thus a feature of at least one embodiment of the invention to provide an automatic analysis of a trainee's identification of one or more suspicious imaging findings.
[0019] The monitor may provide a patient clinical history associated with each record.
[0020] It is thus a feature of at least one embodiment of the invention to allow the trainee to take into account extrinsic information about the patient such as may assist in the analysis of the breast imaging study.
[0021] The records of the data structure may provide records reflecting a normal age distribution. Alternatively or in addition, the records may reflect a normal distribution of breast tissue density types.
[0022] It is thus a feature of at least one embodiment of the invention to provide a simulation that to the extent practical reflects a typical population of patients.
[0023] The data structure may include no less than 50 records.
[0024] It is thus a feature of at least one embodiment of the invention to provide reports that have statistical significance and that provide suitable training opportunity.
[0025] The simulator may provide a time limit for performing a given number of reviews and may permit a given review to be postponed while ultimately requiring completion of any postponed reviews by including them in the report regardless of whether they are subsequently completed.
[0026] It is thus a feature of at least one embodiment of the invention to provide a natural working environment where reviews may be made out of order while preventing subversion of the evaluative aspects of the simulation that might occur if different individuals reviewed self-selected different cases.
[0027] These particular objects and advantages may apply to only some embodiments falling within the claims and thus do not define the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a block diagram of a simulation system according to the present invention providing a display of a data file of breast imaging (mammograms, for example) information by a computer for evaluation by a trainee and an input monitor for a worksheet to be completed by the trainee for evaluating that breast imaging information;
[0029] FIG. 2 is a logical diagram of the data file of breast imaging information of FIG. 1 and a similar data file for receiving input from the trainee evaluating the breast imaging information;
[0030] FIG. 3 is an example worksheet presented on the input monitor for use by the trainee in entering data related to evaluations of the breast imaging (i.e. mammographic) information;
[0031] FIG. 4 is a flowchart of the program executed by the computer of FIG. 1 for implementing a simulation session;
[0032] FIG. 5 is a simplified perspective view of a technique for comparing expert- and trainee-identified breast imaging finding locations for quantitative scoring; and
[0033] FIG. 6 is an example output report from the screening process. Similar outputs would also be made for diagnostic and other high order breast imaging examinations.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0034] Referring now to FIG. 1 , a simulator 10 for mammographic image viewing may provide mammography display monitors 12 a and 12 b for displaying mammographic images 14 of the type acquired with an x-ray mammography unit (not shown). The display monitors 12 will generally provide for at least five megapixel nominal resolution (for example, ten bit pixel resolution and 2048 by 2056 pixels) and will meet the standards of DICOM GSMF Part 14 .
[0035] A work list monitor 16 may also be provided to display a list of cases in which mammograms or other breast imaging studies need to be reviewed and a report input monitor 18 into which clinical report data may be entered by a trainee. The work list monitor 16 and report input monitor 18 may be standard computer monitors.
[0036] Each of the monitors 12 , 16 , and 18 may connect to a simulation computer 20 also connecting to data input devices 21 including, for example, a mouse 22 and keyboard 24 according to techniques and standards well understood in the art. The simulation computer 20 may be a standard desktop computer, for example, capable of running the Windows operating system. The simulation computer 20 may include one or more processors 26 communicating with an electronic memory 28 . The electronic memory 28 may be a logical combination of multiple memory devices including random access memory, disk drive memory and the like.
[0037] The electronic memory 28 may hold a commercially available operating system 30 as well as a simulation program 32 of the present invention as will be described below. In addition, the electronic memory 28 may hold a simulation data file 34 providing data for simulated patient cases that will be reviewed by the trainee and a trainee data file 36 holding information entered by the trainee during the simulation process.
[0038] Referring now to FIG. 2 , the simulation data file 34 may be represented as a logical table having records 38 (represented by rows), each corresponding to a different patient, holding data associated with a breast imaging exam in various attributes 40 (represented by columns). A first attribute 40 a may provide a record number, for example, an integer from one to the total number of records in the simulation data file 34 . In a preferred embodiment, the simulation data file 34 will include at least 100 records and typically more than 50 records. This record number will be used to match records 38 in the simulation data file 34 with corresponding records in the trainee data file 36 .
[0039] A second attribute 40 b may provide for a patient identifier that has been anonymized so as not to identify an actual patient. This patient identifier may be a number or a pseudonym.
[0040] A third attribute 40 c provides a breast imaging exam file 45 including one or more digitized mammographic images (or comparable other breast imaging study; for example ultrasound, MR, tomography) 14 associated with the patient of records 38 . Generally the mammographic images 14 will include left and right mediolateral oblique images and left and right craniocaudal images meeting DICOM standards. In one embodiment, the mammographic images 14 may include some text providing imaging parameters such as: laterality, image view, and radiation dose parameters (kVp, milliamps, compression thickness target and filter) but are otherwise free of any identification of an actual patient or any data indicating diagnostic conclusions.
[0041] A third attribute 40 d may provide for an abbreviated patient history 42 in text form, for example, noting previous breast imaging studies in their dates, family history abreast cancer, patient identified concerns, history of pregnancies if any and the like for the patient of the records 38 .
[0042] A fourth attribute 40 e provides an expert recall instruction 44 prepared by an expert having reviewed the data of attributes 40 c and 40 d and optionally having after-the-fact knowledge of the results of any later history on the patient including a recall examination, biopsy, and the like. The expert recall instruction 44 thus provides, to the greatest practical extent, a correct diagnosis based on the breast imaging exam information informed not only by experience but also by history on the patient. Generally the expert recall instruction 44 will be in the form of a BI-RADS rating of 0, 1, or 2 being the range typically provided after reviewing a screening mammogram according the following table:
[0000]
TABLE I
BI-RADS Assessment
Category
Category Title
0
Need additional
evaluation
1
Normal
2
Benign
3
Probably benign
4
Suspicion of
malignancy
5
Highly suggestive of
malignancy
6
Known biopsy-proven
malignancy
[0043] Note that while the expert recall instruction 44 is informed by the ultimate history of the patient, for example the results of a follow-up biopsy, the recommendation is made from the point of view of an expert viewing the mammographic images 14 and reviewing the patient history 42 only, and thus may indicate a BI-RADS category of 4 or 5, for example, in cases both where history proves a known malignancy or absence of a malignancy. That is, the expert recall instruction 44 represents a nearly infallible expert without knowledge of the future.
[0044] In addition, an attribute 40 f is provided for those records 38 having an expert recall instruction 44 of BI-RADS 4 or 5. This attribute 40 f provides one or more expert predictions 46 including a likelihood that a recall for a second imaging session will lead to a requirement of biopsy (after-recall), a conditional prediction of a type of biopsy that will be required if biopsy is indicated, and a conditional prediction if a biopsy is required as to whether cancer will be detected (an expert predicted “after-recall” assessment). Again these predictions are informed by the patient history and the information in the simulation data file 34 but represent the viewpoint of the nearly infallible expert without knowledge of the future.
[0045] Finally, attributes 40 g may store the coordinates 47 of any suspicious breast imaging finding identifiable from the breast imaging images 14 as informed by subsequent patient history but from the viewpoint of an expert without knowledge of the future.
[0046] The records 38 each may represent actual patients whose data has been anonymized. Desirably the set of records 38 is selected from a larger set of actual patient records to provide a distribution of different ages that represents a realistic population. For example, the age distribution of the records 38 may desirably conform approximately to the following table:
[0000]
TABLE II
<39 years
40-49 years
50-59 years
60-69 years
>70 years
2%
23%
33%
28%
14%
[0047] In addition, the records 38 may be selected among actual records of patients to provide a distribution of breast tissue types (breast fiboglandular tissue density), for example, corresponding proximately to the following table:
[0000]
TABLE III
Heterogeneous
Extremely dense
fatty (<25%
Scattered (25-50%
(51-75%
(<75%
glandular)
glandular)
glandular)
glandular)
8%
49%
39%
4%
[0048] The number of recall instructions typical in mammographic screening of a general population will vary from 5 to 12 percent; however, the simulation data file 34 is adjusted to provide for more recalls in order to maintain the interest level of the trainee and to provide for a more intense training experience. In one embodiment, the records 38 of simulation data file 34 will provide for 75% expert recall instructions 44 of BI-RAD categories 1 or 2 (no recall) and 25% expert recall instructions 44 of BI-RADS category 0 (recall).
[0049] The records 38 are selected so that within the 25% associated with expert recall instructions 44 of BI-RADS 0.17% will ultimately be classified as BI-RADS 1 or 2; 7% will ultimately be classified as BI-RADS 4 and 1% will ultimately be classified as BI-RADS 5. These percentages are based on the total number of records 38 .
[0050] Of the 25% of records 38 having expert recall instructions 44 of BI-RADS 0 that would, upon recall, then be classified as classified BI-RADS 4, 4% will have an expert BI-RADS subcategory of 4a (low suspicion of malignancy), 2% will have an expert BI-RADS subcategory of 4b (intermediate suspicion of malignancy), and 1% will have an expert BI-RADS subcategory of 4c (the moderate concern, but not classic for malignancy).
[0051] Referring now to FIGS. 1 and 2 , the trainee in reviewing the information from each record 38 on the monitors 12 , 16 and 18 , may enter his or her assessment on a worksheet 50 displayed on the report input monitor 18 . Generally, the worksheet 50 will provide for a number of data entry points 52 such as text record boxes, pulldown menus, and the like that may receive data entered by the trainee to be recorded in a trainee data file 36 in machine-readable form. In one embodiment, the worksheet 50 may include data entry points 52 mimicking those in commercial worksheets, such as the PenRad MIS system commercially available from PenRad™ Technologies Inc. of Buffalo, Minn., USA. A representation of portions of the PenRad MIS worksheet will be used in part in the following description of the invention; however, it should be appreciated that the invention is not limited to a particular commercial system or format.
[0052] Referring in particular to FIG. 2 , data from the data entry points 52 on the worksheet 50 may be stored in records 53 of trainee data file 36 , the former records 53 corresponding individually and in number to each of the records 38 in the simulation data file 34 . In this respect, for example, each record 53 may include attribute 54 a providing a record number matching one of the record numbers of attribute 40 a of the simulation data file 34 .
[0053] Generally, it will be of interest to capture all data entered by the trainee at data entry points 52 in the worksheet 50 even if they are not used in the assessment provided by the present invention. Attribute 54 b will hold this data including, for example, text descriptions of the trainee's assessment of the mammogram. All data collected could be used to provide insight into the trainee's evaluation process for breast imaging studies and thus reveal areas needing remediation.
[0054] Data specifically associated with a trainee recall instruction 56 (corresponding to the expert recall instruction 44 although not necessarily in value) will be captured in attribute 54 e described above. This trainee recall instruction 56 provides the trainee's best diagnosis based on the collaboration of information from the mammographic images 14 and patient history 42 expressed in the form of a BI-RADS assessment number (e.g. 0 1, one, or 2).
[0055] Attribute 54 d may store multiple trainee predictions 58 (corresponding generally to the expert predictions 46 although not necessarily in value) described above.
[0056] Finally, the data file 36 may also include attribute 54 e capturing locations for one or more suspicious imaging findings that may be identified by the trainee to be compared against the data of attribute 40 g for the corresponding record 38 .
[0057] Referring now to FIG. 3 , more specifically, the worksheet 50 may provide a text box 70 into which the BI-RAD category of the trainee recall instruction 56 selected by the trainee may be entered after reviewing the mammographic information of a given record 53 . This data may be typed into the text box 70 or entered by means of a pulldown menu or the like.
[0058] The worksheet 50 may present simplified depictions 72 of mammographic images 14 on which the trainee may locate the positions of any suspicious imaging finding evident in the mammographic images 14 by means of position markers 74 . The position markers 74 may be located on both medio-lateral oblique images and cranio caudal images to provide three dimensions of a Cartesian coordinate for the suspicious imaging finding (mass, calcifications, etc). The positional accuracy of this coordinate may be augmented by clock faces 76 showing approximate angular location of the imaging finding in the anterior-posterior direction. As noted above, the coordinates of one or inure located imaging findings may be stored in attribute 54 e.
[0059] In one embodiment of the invention, the worksheet 50 may include a prediction section 77 allowing the trainee to enter, for example, trainee predictions 58 including a trainee predicted “after-recall” assessment indicating a predicted finding after a recall of the patient for additional imaging and diagnosis. This predicted finding after-recall will be in the form of a BI-RADS category, for example, 2, 4, or 5 per Table I above. Category 4 may be broken out into subcategories 4a, 4b, and 4c. Predicted finding after-recall may be entered by marking one checkbox 78 in a table 81 providing for possible BI-RAD values. The checkbox 78 provides data entry points 52 .
[0060] A similar table 83 with checkboxes 85 providing data entry points 52 may allow the trainee to predict the likelihood that a biopsy is required and checkboxes 87 of table 89 may allow the entry by the trainee of a predicted type of biopsy that would be required. These data entry points 52 provide numeric values that match the categories of the expert predictions 46 discussed above but may differ in values from the expert predictions 46 of corresponding records.
[0061] Referring now to FIGS. 1 and 4 , in a simulation, program 32 may be started by trainee as indicated at process block 80 at a given time allocated for the simulation.
[0062] At the start of the simulation and during the simulation, the work monitor 16 provides a list of patient identifiers 41 each representing a case (and underlying records 38 ) that can be reviewed identified by the trainee. With some exceptions noted below, the trainee will typically move through the list in the order in which they are listed on the work monitor 16 .
[0063] At process block 82 , a current record 38 is identified and the mammographic images 14 for that record 38 are displayed on monitors 12 a and 12 b per process block 84 . Optional clinical data 43 may be also displayed, for example, on either work monitor 16 and 18 .
[0064] The trainee may postpone analysis of any given case, for example, as indicated by decision block 86 , in which case it is put back into a queue represented by the list of patient identifiers 41 and marked as incomplete. This postponed case must be completed before conclusion of the simulation session or counted against the trainee in an ultimate report which will be described. This postponing procedure prevents the trainees from cherry picking what may be perceived as easier cases but allows some flexibility in revisiting conclusions.
[0065] For cases that are not postponed, the trainee enters the assessments into the worksheet 50 as indicated by process block 88 .
[0066] If at decision block 90 , the trainee has assessed all of the cases in the simulation data file 34 or a predetermined simulation time has expired, an output report is generated as indicated by process block 92 as will be described below. At early stages of the simulation, however, at decision block 90 , the program will then go back to process block 82 and the next record 38 will be presented to the trainee.
[0067] Referring now to FIG. 6 , the report 94 generated at process block 92 in its simplest form may provide a table indicating in a first column all possible values of BI-RAD categories for the trainee recall instruction 56 . In this case BI-RADS category is 1 and 2 may be grouped together in one row and BI-RADS category 0 separated on a second row. A second column may then indicate the number of times that the trainee recall instructions 56 deviated from the expert recall instructions 44 . Cases that were not fully reviewed by the trainee will count as category errors as well as cases with substantive differences in diagnosis. Thus, for example, a trainee recall instruction 56 having a BI-RADS value of zero (recall) will count as an error when compared to an expert recall instruction 44 having a BI-RADS value of 1 or 2. On the other hand, a trainee recall instruction 56 having a BI-RADS value of 1 (normal) will not count as an error when compared to an expert recall instruction 44 having a BI-RADS value of 1 or 2.
[0068] Provision may be made to allow the trainee to review those cases where deviations occurred and compare them against the expert values. Notably, however, the total number of records, in any given category is not revealed to prevent possible future case counting by individuals in the simulation.
[0069] In addition, a third column may indicate prediction accuracy by the trainee with respect to a comparison of trainee predictions 58 and corresponding expert predictions 46 . In one embodiment, this prediction accuracy number may be calculated by assigning every correct prediction a value of 100 and for cases where the trainee predictions 58 and expert predictions 46 deviated, subtracting from this 100 value 25 times the difference between the trainee predictions 58 and the expert predictions 46 . These weighted accuracy values may then be totaled and divided by the number of records 38 times 100 to obtain the prediction accuracy. Separate prediction accuracy may be provided for each of the different types of predictions including BI-RADS predictions, biopsy predictions and biopsy type predictions. Again, the provisions may be made to allow the trainee to review those cases where deviations occur and to compare them against the expert values.
[0070] Referring now to FIGS. 3 , 5 , 6 , as noted above, the markers 74 entered by the trainee in the worksheet 50 report input monitor 18 , and stored at attribute 40 g , may be used to establish a three dimensional location 100 within a Cartesian coordinate system defined by the simplified images 72 of the suspicious mass identified by the trainee. Similar information stored at attribute 54 e of the trainee data file 36 provides a second location 102 for an expert-located suspicious mass. The vector difference between these two locations 100 and 102 may be compared against a predetermined accuracy threshold to see if a suspicious mass has been properly located.
[0071] If a suspicious mass is identified by the trainee and located within the predetermined accuracy threshold with respect to each location 102 , no error is indicated. If a suspicious mass is identified outside of the predetermined accuracy threshold or no suspicious mass is identified corresponding to a mass at location 102 , a false negative or missed mass is identified in the fourth column of report 94 (with a predicate −). If a suspicious mass is identified having no corresponding location 102 , a false positive is indicated at report 94 (with a predicate +).
[0072] In the event that multiple masses are present, each location 100 is compared to one closest location 102 for this purpose.
[0073] Generally, the output report may satisfy′ part of an audit under the Mammographic Quality Standards Act (MQSA). In this regard, the trainee may obtain all or part of the output report and may provide information such as recall rate, PPV, cancer detection rate and more.
[0074] Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context.
[0075] When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
[0076] References to “a microprocessor” and “a processor” or “the microprocessor” and “the processor,” can be understood to include one or more microprocessors that can communicate in a stand-alone and/or a distributed environment(s), and can thus be configured to communicate via wired or wireless communications with other processors, where such one or more processor can be configured to operate on one or more processor-controlled devices that can be similar or different devices. Furthermore, references to memory, unless otherwise specified, can include one or more processor-readable and accessible memory elements and/or components that can be internal to the processor-controlled device, external to the processor-controlled device, and can be accessed via a wired or wireless network.
[0077] It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications, are hereby incorporated herein by reference in their entireties. | A system simulating the reviewing process of breast imaging examination (i.e. mammographic) information provides a data file of breast imaging information including mammographic (and other breast imaging examinations) images that may be scored by a trainee on computerized worksheet and expert assessments of those images. Quantitative data in the expert assessment may be compared to trainee-entered data recovered from the worksheet to provide an assessment of trainee proficiency in interpreting breast imaging studies. The data file of breast imaging information may be derived from actual clinical data anonymized and selected to provide for realistic yet demanding simulation. | 6 |
RELATED APPLICATION
[0001] This application claims the benefit of priority from Norwegian Patent Application No. 2008 3370, filed on Aug. 1, 2008, the entirety of which is incorporated by reference.
BACKGROUND
[0002] 1. Field of Invention
[0003] This invention relates to a guide arrangement for marine risers, in particular for offshore oil and gas operations.
[0004] 2. Description of Related Art
[0005] Risers are often used for connecting offshore floating platforms or vessels with subsea installations. Such risers may be of various kinds, for example electric cables, fluid pipes, umbilicals or other forms of combined risers being of a flexible character. Typically, these risers are provided at intermediate portions of their length with buoyancy elements so as to obtain a favourable total curve or trajectory of the risers through the water.
[0006] In some cases where dynamic conditions have to be taken into consideration and there is limited space available around the floating platform or vessel concerned, there is a requirement for stabilizing or anchoring the risers so as to reduce or avoid sideways motions thereof. Such motions may be caused by sea currents or waves as well as other influences acting on the risers and/or platform/vessel.
[0007] In a known solution (Subsea Arch System by CRP Group Limited, Lancashire, England) to the above problem there is provided
at least one guide structure for a length of riser, a frame assembly for supporting said guide structure, anchor means at the seabed, tether means connecting said frame assembly to said anchor means, and a buoyancy element for keeping said guide structure at a desired level in the sea during operation.
[0013] More specifically, the known solution involves the use of a fixed guide structure in the form of an arch having an upward or “convex” curvature when installed for stabilizing one or more risers. However, the combination of a light and flexible riser, such as an umbilical or the like, with large dynamic movements as explained above, will require very large bending stiffeners at the entrance and exit of the arch. This involves highly increased costs.
OBJECTS AND SUMMARY
[0014] Substantial improvements in relation to the above are provided according to this invention, by having the guide structure pivotably supported by said frame assembly with a pivot axis being substantially horizontal.
[0015] Advantages obtained with this new guide arrangement are primarily a reduction in bending stress and strain imposed on the riser or umbilical, elimination of very large bend stiffeners, lighter steel structure work and easy installation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Further explanations of the invention follows below with reference to an embodiment of the invention as illustrated in the drawings, of which:
[0017] FIG. 1 is a system overview of a typical riser installation with a “lazy wave” configuration between a surface vessel and the seabed,
[0018] FIG. 2 in elevation shows more in detail the cooperating parts of the guide arrangement included in FIG. 1 , and
[0019] FIG. 3 shows a plan view according to line II-II in FIG. 2 .
DETAILED DESCRIPTION
[0020] In the typical situation of FIG. 1 a vessel 90 on sea surface 100 is connected through a riser 30 to a subsea installation (not shown). At a middle portion of riser 30 there are provided buoyancy elements 33 so as to obtain a desired configuration of the riser as a whole. Thus, as extended from vessel 90 the riser 30 will have an upward inclination before the buoyancy element portion 33 . At this intermediate portion of the riser there may be a need for some stabilization or anchoring of the riser 30 , in particular against movements in a lateral direction related to the general plane followed by riser configuration 30 .
[0021] Thus, a guide arrangement according to the invention providing for such anchoring, is shown in FIG. 1 with bottom anchor blocks 11 and 12 at seabed 200 , with tethers 13 , 14 connected to a frame assembly 10 supporting a guide structure 21 , whereby a buoyancy element 1 serves to keep the guide arrangement at a desired level in the sea. As will be seen better from FIG. 3 , the guide structure 21 may freely and pivotably adjust itself to the inclined configuration or portion of riser 30 passing through guide structure 21 .
[0022] Referring now to FIG. 2 as well as FIG. 3 , the embodiment shown therein comprises two guide structures 21 and 22 provided at respective side parts 15 and 16 of frame 10 , as shown in particular in FIG. 3 . Thus, this embodiment is useful in the case of two more or less parallel risers 30 , which is a situation being quite frequent in actual practice.
[0023] In this case frame 10 has a rectangular main shape and is adapted to have a substantial horizontal orientation in the sea. For this purpose the frame 10 is suspended by brace members 10 A, 10 B, 10 C and 10 D extending at an inclination from respective attachment points at the frame 10 upwards to a common, central suspension point 3 above the horizontal frame 10 . Between buoyancy tether 2 and the top of braces 10 A-D there is provided a swivel 3 S with a vertical axis of rotation. Guide structure 21 is pivotably supported by frame 10 at a pivot axis 21 P whereas guide structure 22 in a corresponding manner is pivotably supported about axis 22 P. Axis 21 P and axis 22 P are both substantially horizontal, so as to make possible an inclined position of guide structures 21 and 22 , for example as shown in FIG. 1 . Such angular movement of the guide structures is individual, allowing for different angles of inclination of the two guides. For such movements it is an advantage that the pivot axes 21 P, 22 P are located at a middle portion of the length of each guide structure 21 , 22 , preferably at a midpoint thereof. Accordingly there will be a kind of balanced arrangement of these guide structures.
[0024] In order that tethers 13 and 14 shall not prevent the movements of guides 21 , 22 they should be attached to frame 10 in a central region along side members 15 and 16 , preferably adjacent to axes 21 P and 22 P, respectively. For increased stability there may also be provided a third (or further) tether(s) with a bottom anchor at a point displaced from the line between anchors 11 an 12 .
[0025] Another feature of significance is also seen from FIG. 3 , namely that the length of each guide structure 21 , 22 is so large as to make the ends of these structures project outside the frame 10 . These ends of the guides are provided with relatively short bend stiffeners 25 - 28 , respectively. Thus, such bending stiffeners have a length being just a small fraction of the length of the guide structures. On the other hand the length of each guide structure 21 , 22 is many times the diameter of the riser 30 . This will provide for a secure angular movement as desired, when in operation the guide structures are under the influence of risers running through them.
[0026] It is preferred according to the invention to let the guide structures 21 and 22 have a basic pipe shape with an essentially rectilinear configuration. Moreover, for the required fixation of risers 30 through guide structures 21 and 22 against longitudinal displacement, clamps 41 and 42 are provided at a middle portion of each guide structure. Such clamps may be of more or less conventional types and are not shown in detail in the drawing.
[0027] Mounting of the guide structures 21 , 22 onto a riser 30 can be done at a laying vessel when deploying the riser at the offshore installation site. In the case of pipe-shaped guides (see FIGS. 2 and 3 ) the riser may be threaded through its guide or the guide may be split longitudinally for placing the riser first in one half pipe whereupon the other half is mounted so as to form a complete, closed guide containing a length of the riser. Then the assembly is deployed into the sea and afterwards each guide is connected to the frame pivot. The arrangement of frame 10 , anchors 11 , 12 , tether 2 and buoyancy element 1 can be installed before or after deployment of the riser 30 with the guides mounted thereto.
[0028] It will be understood that many modifications are possible, deviating from the exemplary embodiment shown in FIGS. 1-3 . The riser configuration may be different and the present guide arrangement could be located at other portions of the riser configuration than illustrated in FIG. 1 . Anchors 11 and 12 could be of any other type of anchor than the gravitation blocks shown, for example pile anchors. There may also be modifications of guide arrangements with only one guide structure, and in such case the frame assembly may be much simpler than illustrated in the drawing. | Guide arrangement for marine risers, in particular for offshore oil and gas operations. The guide arrangement has at least one guide structure ( 21, 22 ) for a length of riser, a frame assembly ( 10, 10 A-D) for supporting said guide structure, anchor means ( 11, 12 ) at the seabed, tether means ( 13, 14 ) connecting said frame assembly to said anchor means, and a buoyancy element ( 1 ) for keeping said guide structure ( 21, 22 ) at a desired level in the sea during operation. The guide structure ( 21, 22 ) is pivotably supported by said frame assembly ( 10, 10 A-D) with a pivot axis ( 21 P, 22 P) being substantially horizontal. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 13/373,641 filed Nov. 22, 2011 and a continuation in part of Ser. No. 13/317,624 filed Oct. 24, 2011.
FIELD OF THE INVENTION
This invention relates generally to docks and dock kits and, more specifically, to a universal dock kit.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
None
REFERENCE TO A MICROFICHE APPENDIX
None
BACKGROUND OF THE INVENTION
The length and width of lake docks vary depending on the type of lakeshore as well as the preference of the lakeshore owner. The requests for various widths and lengths of docks usually requires that docks be made to order for each application sometimes in dock lengths which preclude conventional shipping methods. That is, most conventional carriers have a maximum length for goods that they will transport or if they do transport longer length goods the costs of the transport becomes so costly it becomes uncompetitive to make and ship the dock to a customer in a remote location.
While posts for supporting a dock can be located at different positions along the dock in order to have a stable dock surface it is desirable to have a set of at least two elongated dock beams that run the entire length of the dock for supporting the dock planks thereon. With the use of continuous elongated dock beams one is assured that the dock planks can be secured to the dock beams to form a stable walking surface. One such dock beam that is suitable for forming elongated dock beams is the Vee shaped dock beams used in docks sold by R & D Manufacturing Inc. of Forest Lake Minn.
Aside from the difficulty in shipping docks in dock kit form another difficulty is that different length dock beams need to be fabricated for each different dock length that a customer orders, which results in requiring a large inventory of dock beams in order to anticipate the orders for different length docks. On the other hand additional dock planks can easily be added to the dock kit to accommodate requests for different length docks. Thus, there is a need for a universal dock kit that could be assembled in different lengths and also avoids the shipping problems when the length of the dock beams exceed the carriers standard capacity.
The invention described herein comprises a universal dock kit for in situ formation of dock beams of various length docks without incurring the costs and shipping restrictions on oversize items and without having an excessive inventory of dock beams.
SUMMARY OF THE INVENTION
A universal dock and universal dock kit suitable for shipping from a manufacturing site to a lake site where a dock can be erected using in situ formation of elongated dock beams wherein the elongated dock beams supporting the dock planks have a length that is greater than the length of any of the beams in the dock kit. The dock kit including mateable beams that include male and female beams that have surfaces that are mateable and securable to each other through fasteners to form the elongated dock beam with each of the shorter male and female beams having supports thereon for receiving and holding a plurality of dock planks thereon and for holding the mateable beams in an interlocked condition while stiffening the elongated beam. The use of dock beams that can be assembled into different lengths allows the same dock kit to be used for a range of different length docks by merely adding additional dock planks to the dock kit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an example of a dock kit of the invention;
FIG. 2 is a perspective view of mateable beams in surface-to-surface engagement with each other;
FIG. 2A is an end view of one of the mateable beams;
FIG. 2B is an end view of a mateable beam for forming surface to surface contact with the mateable beam of FIG. 2A ;
FIG. 3 shows two mateable beams located in an overlapping condition to form a dock beam;
FIG. 4 shows two mateable beams located in a different overlapping condition to form a dock beam longer than the dock beam of FIG. 3 ;
FIG. 5 shows two mateable beams located in a further overlapping condition to form a dock beam longer than the dock beam of FIG. 4 ;
FIG. 6 is a perspective view of the overlapping section of two mateable beams; and
FIG. 7 is a bottom view of two sets of overlapping beams forming dock beams for supporting a plurality of dock planks thereon.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a dock kit 10 including dock planks 23 - 26 , dock hardware 20 , dock posts 15 - 18 , a first set of mateable beams 11 and 12 and a second set of mateable beams 51 and 52 . Each of the set of mating beams can be overlapped and assembled to each other for forming an elongated dock beam which has a length longer than the length of the individual mating beams but less than the end to end length of the individual mating beams. The dock planks 23 - 26 can be secured to a pair of dock beams through the dock hardware 21 . The dock posts 15 - 18 can be used to support the dock above the water.
In the example shown in FIG. 1 a first set of mateable beams 11 and 12 comprise a metal vee shaped male beam 11 having a fixed length L and a metal vee shaped female beam 12 having a fixed length L. Typically, beams 11 and 12 may be formed from a metal such as sheet aluminum, however, other materials may be used without departing from the spirit and scope of the invention. Beam 11 includes a set of lateral flanges 43 and 44 with flange 43 having a first set of spaced apart holes 11 a and flange 44 having a second set of spaced apart holes 11 b with each set of spaced apart holes extending in a regular pattern along the flanges and a third set of spaced apart holes 11 c extending in a regular pattern along the apex end of the beam 11 . Similarly, beam 12 includes a set of lateral flanges 33 and 34 with flange 33 having a first set of spaced apart holes 12 a and flange 34 having a second set of spaced apart holes 12 b a third set of spaced apart holes 12 c extending in a regular pattern along the apex end of the beam 12 which each set of spaced apart holes extending in a regular pattern along the respective flanges and the apex end of beam 12 with the spacing between holes arranged so that a portion of the male beam 11 can be overlapped and secured to the female beam 12 through the extension of a set of fasteners 21 , such as bolts, through the aligned holes in the flanges and the apex of the beams 11 and 12 .
Similarly, the second set of mateable beams 51 , 52 also comprises a first vee shaped male beam 51 having a first fixed length L and a second vee shaped female beam 52 having a second fixed length L. Beam 51 includes a set of lateral flanges 53 and 54 with flange 53 having a first set of spaced apart holes 51 a and flange 54 having a second set of spaced apart holes 51 b and a third set of spaced apart holes 51 c extending in a regular pattern along the apex end of the beam 51 with each set of spaced apart holes extending in a regular pattern. Similarly, beam 52 includes a set of lateral flanges 55 and 56 with flange 55 having a first set of spaced apart holes 52 a and flange 56 having a second set of spaced apart holes 52 b and a third set of spaced apart holes 52 c extending in a regular pattern along an apex end of the beam 52 which each set of spaced apart holes extending in a regular pattern along the respective flanges and the apex end with the spacing between holes arranged so that a portion of the male beam 51 can be overlapped and secured to the female beam 52 through the extension of a set of fasteners, such as bolts, through the aligned holes in the flanges and the apex end of the beams 51 and 52 .
While dock beams can be manufactured in longer lengths the limitation on the length of goods that can be shipped from place to place makes it unfeasible to manufacture longer dock beams since not only is the shipping more difficult the cost of shipping increases substantially if a dock beam exceeds a certain length. Typically, most shippers limit the length of an article to a maximum of 10 feet in length, however, homeowners often need dock lengths in excess of ten feet, which requires having dock beams in excess of 10 feet.
A feature of the beams of the dock kit 10 is the use of shorter beams that can be assembled to each other to form a longer dock beam without the need for separate gusset plates or other tie members. A further feature is the ability to assemble shorter beams into a longer beam without the need of distorting the beams during the assemble of the beams into an elongated dock beam since the beams are mateable with each other thus reducing stress points on the elongated beam. A benefit of the inventions is that even though the mating beams may not be identical that when assembled the beams so closely resemble each other in physical appearance and size that the dock beams have a similar visual appearance to an observer so that the assembled dock beam appears as a continuous beam.
To appreciate the feature of the mating beams reference should be made to FIGS. 2 , 2 A and 2 B which show one example of the mateable beams for use in dock kit 10 . FIG. 2 shows a perspective end view of beam 11 , which is located within an internal cavity of beam 12 . In the example shown the beams 11 and 12 have a surface-to-surface contact between the inside surface 11 c of beam 11 the outside surface 12 c of beam 12 .
FIG. 2A shows an end view of beam 12 and FIG. 2B shows an end view of beam 11 . The beam 11 includes angled sides 41 and 42 terminating in an internal apex 40 having an internal radius of curvature R 1 and includes an internal beam contact surface 11 d . Beam 11 includes a first lateral flange 43 and a second lateral flange 44 for supporting dock planks thereon and for securing beam 11 beam 12 to each other.
Similarly, FIG. 2A shows an end view of beam 12 revealing the angled sides 32 and 36 terminating in an outside apex end 35 having an external radius of curvature R 1 and an external beam contact surface 12 d . A first lateral flange 33 for supporting dock planks thereon extends from side 42 and a second lateral flange 44 for supporting dock planks thereon extends from side 41 . The beam 12 includes angled sides 32 and 36 terminating in an external apex end 40 having an external radius of curvature R 1 . Beam 12 includes a first lateral flange 33 and a second lateral flange 34 for supporting dock planks thereon and for securing dock planks to beam 11 beam 12 .
As can be seem in FIG. 2 , FIG. 2A and FIG. 2 b the apex end of the female beam 11 has an inside radius of curvature R 1 and the apex end of male beam 12 has an external radius of curvature R 1 where the external radius of curvature of the male beam is equal or less than the inside radius of curvature of the female beam to enable beams 11 and 12 to mate in surface to surface contact with an inside surface 11 d of female beam 11 with an outside surface 12 d as illustrated in FIG. 2 and FIG. 6 .
In the example shown the fixed length of the male beam and the fixed length of the female beam are each less than ten feet in order to accommodate carrier restrictions. In the in situ formation of an elongated dock beam described herein the lateral flanges of each of the male beam 12 and the female beam 11 have regular spaced holes, so the female beam 11 and the male beam 12 can be overlapped and secured to each other in a variety of different lengths as evidenced by dock beams 50 , 51 and 52 , which are shown in FIG. 3 , FIG. 4 and FIG. 5 .
FIG. 3 shows that the male beam 12 fits in the cavity of the female beam 11 with the flanges and the apex end of each beam in contact with each other and a set of fasteners 21 extending therethrough with nuts 21 a thereon to hold the flanges and the apex end of the beams proximate each other so that beam 50 has a length L 2 .
A further benefit from the mateable beams is that the overlapping section of the beams interlock with other in surface to surface contact so that the top fasteners and bottom fasteners 21 and 21 a , which secure the flanges and apex ends of the beams to each other enable one to form the elongated dock beam from the shorter mateable beams. A further benefit of the overlapped beams is that the overlapping of the beams produce an elongated beam that is stiffer than an individual one-piece beam of similar length since the overlapped regions reinforce one another.
FIG. 4 shows the mateable beams 11 and 12 which have been in situ formed into a dock beam 51 having a length L 3 and FIG. 5 shows the mateable beams 11 and 12 which have been in situ formed to a beam 52 having a length L 4 through a set of fasteners 21 a and 21 b . In each case the length of the beam formed by the overlapping beams 11 and 12 is greater than the length of either beam 11 or beam 12 but is less than the end-to-end length of beams 11 and 12 since a portion of each beam overlap each other. Although more material is required for fabricating a dock beam of given length if the dock beam is made of shorter beams the cost premium has been found to be insignificant in comparison to the costs and problems in shipping longer dock beams that exceed surface carriers normal size limit. In each case the spaced apart holes may be used to obtain the various lengths. If desired an operator may elect to form additional holes for additional fasteners if so desired.
In the example shown the fixed length of the female beam and the fixed length of the male beam in the dock kit are the same length although one may be longer than the other without departing from the spirit and scope of the invention.
While dock kit 10 shows examples of four dock planks 23 , 24 , 25 , and 26 , which are to be fixedly mounted transversely to the dock beams 11 and 12 with the hardware fasteners 21 shown in box 20 . The actual number of dock planks included with the dock kit will depend on the ultimate length of the dock. Also included in dock kit 10 are a set of posts 15 , 16 , 17 , and 18 with post 15 having a footpad 15 a , post 16 having a footpad 16 a , post 17 having a footpad 17 a and post 18 having a footpad 18 a . Similarly, the actual number of dock planks included with the dock kit will depend on the ultimate length of the dock. Thus a dock kit may contain more or less items with a basic dock kit generally including at least two sets of dock beams that can be assembled into longer dock beams.
FIG. 6 shows in perspective view an example of the overlapping of the first set of mateable beams 11 and 12 to form a single dock beam through the alignment of holes 11 a in beam 11 with holes 12 a in beam 12 and the extension of a bolt 21 through the spaced apart holes in lateral flanges on each of the beams as well as through the apex end of each of the beams.
Thus, in one mode the invention comprises a dock kit 10 including a set of dock planks 23 - 26 , a female beam 11 having a first fixed length L 1 and an apex end 40 having a set of regular spaced openings 11 c with an inside beam contact surface 11 d and a pair of opposite extending lateral flanges, a male beam 12 having a second fixed length and an apex end with an outside beam contact surface 12 d and a pair of opposite extending lateral flanges 43 , 44 where the outside beam contact surface 12 d of the male beam 12 engages the inside contact beam surface 11 d of the female beam when the female beam and the male beam are overlapped to thereby form an elongated dock beam such as dock beam 50 , 51 , or 52 , which is of greater length than the length of either the female beam 11 or the male beam 12 but less than the end-to-end length of the female beam 11 and the male beam 12 .
FIG. 3 is a side view of beam 11 and beam 12 and illustrates how beam 11 and beam 12 which each have a length L 1 can be assembled into a single dock beam having a length L 2 which is longer than either the dock beam 12 or dock beam 11 but less than an end-to-end length of beam 11 and beam 12 . The dock beam 11 and dock beam 12 are secured to each other through a set of fasteners 21 and 21 b , which may be bolts with nuts.
FIG. 4 is a further side view of dock beam 11 and beam 12 and illustrates how beam 11 and dock beam 12 which each have a length L 1 can be assembled into a single dock beam having a length L 3 , which is longer than the dock beam 12 or dock beam 11 but less than an end-to-end length of beam 11 and beam 12 . The dock beam 11 and dock beam are secured to each other through a set of fasteners 21 and 21 b.
FIG. 5 is a side view of dock beam 11 and dock beam 12 and illustrates how beam 11 and beam 12 which each have a length L 1 can be assembled into a single dock beam having a length L 4 which is longer than the dock beam 12 or dock beam 11 but less than an end-to-end length of beam 11 and beam 12 . The dock beam 11 and dock beam 12 are secured to each other through a set of fasteners 21 and 21 a . Typically when the beams are secured to each other the beams include an overlap of at least two feet. However, the length of the overlap will depend on the material that the beams 11 and 12 are made from as well as the thickness and the shape of the mating beams. While mating beams 11 and 12 are shown as Vee shaped beams it is envisioned that other beams of other mateable shapes may also be used without departing from the spirit and scope of the invention described herein. While the mateable beams are secured with fasteners on the flange and preferably on the apex end of the beams in some cases the fasteners may be located on the sides of the beam to provide for securing the beams in another location other than the apex of the beam. For example, the spaced apart holes may be located in sides 12 , 36 and 42 , 41 without departing from the spirit and scope of the invention.
FIG. 7 shows a view of the underside of a dock having a first set of dock beams 11 and 12 located in an overlapped condition and a second set of dock beams 51 and 52 which are also located in an overlapped condition with each of the beams located parallel to each other and extending transverse to a set of dock planks 23 - 31 which are fastened thereto to form a dock 53 .
Thus one aspect of the invention includes a method of manufacture of a dock kit 10 for shipment for on site assembly where the assembled dock has a length L 3 by forming a male beam 12 of a first length L 1 and a female beam 11 of a second length L 2 where the length L 1 or L 2 is less than L 3 , forming a further male beam 51 of a further length L 1 and a further female beam 52 of a further length L 2 where the length L 1 or L 2 is less than L 3 , forming a set of mating features such as a vee shape with an apex end in each of the male beams and each of the female beams. One then prepares customer instructions on assembly of the first male beam and the first female beam to form a first dock beam of length L 3 where L 3 is greater than L 1 and for assembling the further female beam and the further male beam to form a second dock beam of length L 3 where L 3 is greater than L 1 or L 2 including overlapping the first male beam to the first female beam to form the first elongated dock beam and securing the male beam to the female beam through fasteners 20 extending through aligned holes in flanges formed in the female beam and flanges formed in the male beam and through an apex end of the male beam and an apex end of the female beam and overlapping the further male beam to the further female beam to form the second dock beam and securing the further male beam to the further female beam through fasteners extending through aligned holes in the flanges and the apex end of each of the further male beam and the further female beam.
While the examples show the spaced apart holes located in the male and female beam in some cases the spaced apart holes may be formed on site when the male and female beam are located in a face to face condition as shown in FIG. 2 . | A dock and dock kit suitable for shipping from a manufacturing site to an erection site where a dock can be erected having elongated dock beams with a length that is greater than the length of any of the beams in the dock kit and the mateable beams have surfaces that are mateable and securable to each other through fasteners to form elongated dock beams with each of the mateable beams having supports thereon for receiving and holding a plurality of dock planks thereon. | 4 |
FIELD OF THE INVENTION
The present invention relates to power supplies, systems, and methods for chemical vapor deposition.
BACKGROUND OF THE INVENTION
Chemical vapor deposition (CVD) is a process whereby a film is deposited on a substrate by reacting chemicals together in the gaseous or vapor phase to form a film. The gases or vapors utilized for CVD are gases or compounds that contain the element to be deposited and that may be induced to react with a substrate or other gas(es) to deposit a film. The CVD reaction may be thermally activated, plasma induced, plasma enhanced or activated by light in photon induced systems.
CVD is used extensively in the semiconductor industry to build up wafers. CVD can also be used for coating larger substrates such as glass and polycarbonate sheets. Plasma enhanced CVD (PECVD), for example, is one of the more promising technologies for creating large photovoltaic sheets, LCD screens, and polycarbonate windows for automobiles.
FIG. 1 illustrates a cut away of a typical PECVD system 100 for large-scale deposition processes—currently up to 2.5 meters wide. This system includes a vacuum chamber 105 of which only two walls are illustrated. The vacuum chamber 105 houses a linear discharge tube 110 . The linear discharge tube 110 is formed of an inner conductor 115 that is configured to carry a microwave signal, or other signals, into the vacuum chamber 105 . This microwave power radiates outward from the linear discharge antenna 115 and ignites the surrounding support gas 120 that is introduced through the support gas tube 120 . This ignited gas is a plasma and is generally adjacent to the linear discharge tube 110 . Radicals generated by the plasma and electromagnetic radiation disassociate the feedstock gas(es) 130 introduced through the feedstock gas tube 125 thereby breaking up the feedstock gas to form new molecules. Certain molecules formed during the dissociation process are deposited on the substrate 135 . The other molecules formed by the dissociation process are waste and are removed through an exhaust port (not shown)—although these molecules tend to occasionally deposit themselves on the substrate. This dissociation process is extremely sensitive to the amount of power used to generate the plasma.
To coat large substrate surface areas rapidly, a substrate carrier (not shown) moves the substrate 135 through the vacuum chamber 105 at a steady rate, although the substrate 135 could be statically coated in some embodiments. As the substrate 135 moves through the vacuum chamber 105 , the dissociation should continue at a steady rate and target molecules from the disassociated feed gas theoretically deposit on the substrate, thereby forming a uniform film on the substrate. But due to a variety of real-world factors, the films formed by this process are not always uniform.
Nonconductive and conductive films deposited utilizing plasma enhanced chemical vapor sources have been achieved with many types of power sources and system configurations. Most of these sources utilize microwaves, radio frequency (RF), high frequency (HF), or very high frequency (VHF) energy to generate the excited plasma species.
Those of skill in the art know that for a given process condition and system configuration of PECVD, it is the average power introduced into the plasma discharge that is a major contributing factor to the density of radicalized plasma species produced. These radicalized plasma species are responsible for disassociating the feedstock gas. For typical PECVD processes, the necessary density of produced radicalized species from the plasma must be greater than that required to fully convert all organic materials. Factors such as consumption in the film deposition processes, plasma decomposition processes of the precursor materials, recombination losses, and pumping losses should be taken into consideration.
Depending upon the power type, configuration and materials utilized, the required power level for producing the necessary density of radicalized plasma species can unduly heat the substrate beyond its physical limits, and possibly render the films and substrate unusable. This primarily occurs in polymer material substrates due to the low melting point of the material.
To reduce the amount of heat loading of the substrate, a method of high power pulsing into the plasma, with off times in between the pulsing, can be used. This method allows the plasma during the short high energy pulses to reach saturation of the radicalized species required for the film deposition process and loss to occur, while reducing the instantaneous and continuous heating of the substrate through the reduction of other forms of electromagnetic radiation.
Film property requirements are achieved by setting the process conditions for deposition, including the power levels, pulsing frequency and duty cycle of the source. To achieve required film properties the structure and structural content of the deposited film must be controlled. The film properties can be controlled by varying the radical species content, (among other important process parameters), and as stated in the above, the radical density is controlled primarily by the average and peak power levels into the plasma discharge.
To achieve several important film properties, and promote adhesion to some types of substrates, the films organic content must be finely controlled, or possibly the contents must be in the form of a gradient across the entire film thickness. Current technology, which enables control of only certain process parameters, cannot achieve this fine control. For example, current technology consists of changing the deposition conditions, usually manually or by multiple sources and chambers with differing process conditions, creating steps in the film stack up to achieve a gradient type stack. Primarily the precursor vapor content, system pressure, and or power level at one or more times is used to develop a stack of layers. These methods are crude at best and do not enable fine control. Accordingly, a new system and method are needed to address this and other problems with the existing technology.
SUMMARY OF THE INVENTION
Exemplary embodiments of the present invention that are shown in the drawings are summarized below. These and other embodiments are more fully described in the Detailed Description section. It is to be understood, however, that there is no intention to limit the invention to the forms described in this Summary of the Invention or in the Detailed Description. One skilled in the art can recognize that there are numerous modifications, equivalents and alternative constructions that fall within the spirit and scope of the invention as expressed in the claims.
One embodiment includes generating a first electrical pulse having a first pulse amplitude; using the first electrical pulse to generate a first density of radicalized species; disassociating a feedstock gas using the radicalized species in the first density of radicalized species, thereby creating a first deposition material; depositing the first deposition material on a substrate; generating a second electrical pulse having a second pulse amplitude, wherein the second pulse amplitude is different from the first pulse amplitude; using the second electrical pulse to generate a second density of radicalized species; disassociating a feedstock gas using the radicalized species in the second density of radicalized species, thereby creating a second deposition material; and depositing the second plurality of deposition materials on the first deposition material.
BRIEF DESCRIPTION OF THE DRAWINGS
Various objects and advantages and a more complete understanding of the present invention are apparent and more readily appreciated by reference to the following Detailed Description and to the appended claims when taken in conjunction with the accompanying Drawing wherein:
FIG. 1 illustrates one type of PECVD system;
FIG. 2 a illustrates a power supply for a PECVD system in accordance with one embodiment of the present invention;
FIG. 2 b is an alternative depiction of a power supply for a PECVD system in accordance with one embodiment of the present invention;
FIG. 3 illustrates one example of a pulse-width modulated power signal;
FIG. 4 illustrates one example of a pulse-amplitude modulated power signal;
FIG. 5 illustrates one example of a frequency-modulated power signal;
FIG. 6 a illustrates one example of a gradient film formed using pulse-width modulation;
FIG. 6 b illustrates one example of a multi-layer gradient film formed using pulse-width modulation;
FIG. 7 a illustrates one example of a gradient film formed using amplitude-width modulation;
FIG. 7 b illustrates one example of a multi-layer gradient film formed using amplitude-width modulation; and
FIGS. 8 a - 8 d illustrate the development of a multi-layer gradient film over time using a pulse-width modulated power signal.
DETAILED DESCRIPTION
In some PECVD processes the typical radical lifetime (time for the loss of and consumption of the radical species) is long enough so that there can be an off time of the plasma during which the radical density remaining is gradually consumed by the deposition of the film and loss mechanisms. Therefore, by controlling the total radical density during these on and off times of the plasma the chemical makeup of the film can be altered, as well as the over all layer properties of the film.
By modulating the power level into the plasma, the on time of the plasma and the timing between the power pulses, the user can make films that were not achievable before in PECVD. The layers could be a single gradient layer or a multiple stack of hundreds to thousands of micro layers with varying properties between each layer. Both processes can create a unique film.
FIG. 2 a illustrates a system constructed in accordance with one embodiment of the present invention. This system includes a DC source 140 that is controllable by the pulse control 145 . The terms “DC source” and “DC power supply” refer to any type of power supply, including those that use a linear amplifier, a non-linear amplifier, or no amplifier. The DC source 145 powers the magnetron 150 , which generates the microwaves, or other energy waves, that drive the inner conductor within the linear discharge tube (not shown). The pulse control 145 can contour the shape of the DC pulses and adjust the set points for pulse properties such as duty cycle, frequency, and amplitude. The process of contouring the shape of the DC pulses is described in the commonly owned, entitled “SYSTEM AND METHOD FOR POWER FUNCTION RAMPING OF MICROWAVE LINEAR DISCHARGE SOURCES,” which is incorporated herein by reference.
The pulse control 145 is also configured to modulate the DC pulses, or other energy signal, driving the magnetron 150 during the operation of the PECVD device. In some embodiments, the pulse control 145 can be configured to only modulate the signal driving the magnetron 150 . In either embodiment, however, by modulating the DC pulses, the power level into the plasma can also be modulated, thereby enabling the user to control radical density and make films that were not achievable before in PECVD. This system can be used to form variable, single gradient layers or a multiple stack of hundreds to thousands of micro layers with varying properties between each other.
FIG. 2 b illustrates an alternate embodiment of a power supply. This embodiment includes an arbitrary waveform generator 141 , an amplifier 142 , a pulse control 145 , a magnetron 150 , and a plasma source antenna 152 . In operation, the arbitrary waveform generator 141 generates a waveform and corresponding voltage that can be in virtually any form. Next, the amplifier 142 amplifies the voltage from the arbitrary waveform generator to a usable amount. In the case of a microwave generator (e.g., the magnetron 150 ) the signal could be amplified from +/ — 5 VDC to 5,000 VDC. Next, the high voltage signature is applied to the magnetron 150 , which is a high frequency generator. The magnetron 150 generates a power output carrier (at 2.45 GHZ in this case) that has its amplitude and or frequency varied based upon the originally generated voltage signature. Finally, the output from the magnetron is applied to the source 152 to generate a power modulated plasma.
Signal modulation can be applied by the pulse control 145 to the arbitrary waveform generator 141 . Signal modulation is a well-known process in many fields—the most well known being FM (frequency modulated) and AM (amplitude modulated) radio. But modulation has not been used before to control film properties and create layers during PECVD. Many forms of modulation exist that could be applied to a waveform power level, duty cycle or frequency, but only a few are described below. Those of skill in the art will recognize other methods. Note that modulation is different from simply increasing or decreasing the power or duty cycle of a power signal into a source.
FIG. 3 illustrates pulse-width modulation, which varies the width of pulse widths over time. With pulse-width modulation, the value of a sample of data is represented by the length of a pulse.
FIG. 4 illustrates pulse-amplitude modulation, which is a form of signal modulation in which the message information is encoded in the amplitude of a series of signal pulses. In the case of plasma sources the voltage, current or power level can be amplitude modulated by whatever percentage desired.
FIG. 5 illustrates frequency modulation (FM), which is the encoding of information in either analog or digital form into a carrier wave by variation of its instantaneous frequency in accordance with an input signal.
Referring now to FIGS. 6 and 7 , they show two examples of multi-layer films that could be produced with two differing forms of modulation, pulse-width and pulse-amplitude modulation. Both of these figures illustrate the film layers deposited on the substrate and the corresponding modulated power signal that is used to generate the plasma. Notice that the power signal is modulated during the deposition process, which differs from establishing and leaving initial set points that are static during the deposition process.
Referring first to FIG. 6 a, it illustrates a variable film 157 produced by pulse-width modulation. In this embodiment, the cycle between short pulse widths and long pulse widths is relatively long. This long cycle produces a variable-gradient coating on the substrate that varies through its thickness from a flexible, organo-silicon film located next to the substrate to a rigid, dense SiO2 or SiOxNy film. The film produced by this process becomes harder and more rigid as it extends out from the substrate.
A benefit is realized with this single, variable gradient layer because the flexible, softer portion of the film bonds better to the substrate than would the dense, rigid portion. Thus, the pulse width modulation allows a film to be created that bonds well with the substrate but also has a hardened outer portion that resists scratches and that has good barrier properties. This type of film could not be efficiently created without a modulated power signal.
By changing the modulation of the power signal, a multilayer gradient coating can be deposited on the substrate. FIG. 6 b illustrates this type of substrate and film 160 . In this embodiment, the cycle between short pulse widths and long pulse widths is relatively short, thereby creating multiple layers. These individual layers can also vary from less dense to more dense within a single layer—much as the single gradient layer in FIG. 6 a does.
In this embodiment, a less-dense, organo-silicon layer is initially deposited on the substrate. This type of layer bonds best with the substrate. The next layer is slightly more dense, and the third layer is an almost pure SiO2 or SiOxNy layer, which is extremely dense and hard. As the pulse width modulates to shorter pulse widths, the next layer is again a less-dense, organo-silicon layer that bonds easily to the dense layer just below. This cycle can repeat hundreds or even thousands of times to create a multilayer, gradient film that is extremely hard, resilient, and with good barrier properties. Further, this film can be produced with a minimal amount of heat and damage to the substrate.
FIGS. 7 a and 7 b illustrate another series of films similar to those shown in FIGS. 6 a and 6 b . These films, however, are created using pulse-amplitude modulation. Again, both a single gradient film 165 or a multilayer gradient film 170 can be created using modulation techniques. Note that this process works for almost any precursor and is not limited to silicon-based compounds.
Variable films can be created with other modulation techniques. In fact, there are many modulation technologies that could be implemented to effectively control the radical species density and electromagnetic radiation in relation to time, including, PWM—Pulse Width Modulation, PAM—Pulse Amplitude Modulation, PPM—Pulse Position Modulation, AM—Amplitude modulation, FM—Frequency Modulation, etc. Again, these techniques involve modulating a power signal during film deposition rather than setting an initial power point or duty cycle.
Referring now to FIGS. 8 a through 8 d, they show an example of pulse-width modulation and its possible affects on the films properties for SiO2 and or SiOxNy. A sine wave signal is used to drive the pulsing frequency at a fixed peak power level to increase or decrease the short term average power into the plasma. The sine wave shown is the drive signal, and it also indicates power.
At the beginning portion (left side) of the FIG. 8 a , the modulation increases the power level per given time interval by increasing the on-time and decreasing the off-time of the plasma, thus increasing the instantaneous radical density and electromagnetic components of the plasma. This process increases the radical density to the point at which all material was converted and deposited and a new material is the dominate contributor to the growing film stack, SiO2 or SiOxNy. FIG. 8 b shows the dense layer formed next to the substrate during this phase.
In the center of the drive signal, the on-time is at its lowest and off-time at its highest value. This effect decreases the instantaneous radical density to the point at which all material was consumed and the precursor material again becomes the dominate contributor to the growing film stack. FIG. 8 c shows the less-dense, more-organic layer formed during the second phase. This layer is deposited on the first layer.
Finally in the last portion of the waveform, the process returns to saturation of the radical density like in the first portion of the waveform. This phase deposits a hardened, dense layer. FIG. 8 d shows the dense, third layer deposited on the second layer. Accordingly, the three phases together leaving an inter layer of organic material between two hard, dense layers—thereby introducing flexibility into the entire film stack.
These modulation techniques can be used during inline or dynamic deposition processes. By utilizing these modulation techniques with the dynamic deposition process, it is possible to produce alignment layers for applications such as LCD displays, thereby replacing the polymide layers presently being used.
In summary, this discovery allows the user to achieve PECVD films not possible in the past, possibly with extended film properties and qualities not possible to date. The higher quality thin films are achieved from the ability to actively control the plasmas radical/electromagnetic radiation densities in continuous way per unit time by contouring the average and or peak power level per time interval. The drive waveform can be any waveform or even an arbitrary function. This technique can also be used to control the localized etching rate when the source and system is configured to do so.
In conclusion, the present invention provides, among other things, a system and method for controlling deposition onto substrates. Those skilled in the art can readily recognize that numerous variations and substitutions may be made in the invention, its use and its configuration to achieve substantially the same results as achieved by the embodiments described herein. Accordingly, there is no intention to limit the invention to the disclosed exemplary forms. Many variations, modifications and alternative constructions fall within the scope and spirit of the disclosed invention as expressed in the claims. | A method of generating a film during a chemical vapor deposition process is disclosed. One embodiment includes generating a first electrical pulse having a first pulse amplitude; using the first electrical pulse to generate a first density of radicalized species; disassociating a feedstock gas using the radicalized species in the first density of radicalized species, thereby creating a first deposition material; depositing the first deposition material on a substrate; generating a second electrical pulse having a second pulse amplitude, wherein the second pulse amplitude is different from the first pulse width; using the second electrical pulse to generate a second density of radicalized species; disassociating a feedstock gas using the radicalized species in the second density of radicalized species, thereby creating a second deposition material; and depositing the second plurality of deposition materials on the first deposition material. | 2 |
BACKGROUND AND SUMMARY
This invention relates to a leveling system for use with a vehicle, such as a recreational vehicle.
Various systems for leveling a recreational vehicle are known, such as are shown in U.S. Pat. Nos. 4,061,309; 4,165,861; 4,597,584; 4,743,037; and 4,746,133. These patents all show a leveling system having four jacks located one adjacent each corner of the vehicle.
It is an object of the present invention to provide a three-leg system for leveling a vehicle. It is a another object of the invention to provide a leveling system which is simple and efficient in its construction, and which is easily operated and provides highly satisfactory performance. It is a further object of the invention to provide a vehicle leveling system which is efficiently packaged and provides a minimal number of hydraulic and electrical connections to install. It is a further object of the invention to provide a leveling system which is adaptable for installation on a wide variety of vehicles.
In accordance with the invention, a system for leveling a vehicle, such as a recreational vehicle, comprises a number of extendable and retractable fluid-operated jacks mounted to the frame of the vehicle. In a preferred form, the system includes three jacks, two of which are located at opposite sides of the rear of the vehicle frame, with the third jack being centrally located at the front end of the vehicle frame. The system further includes a selectively operable source of pressurized fluid, such as a hydraulic pump, for supplying pressurized fluid from a reservoir. Broadly, the system includes a leveling arrangement for selectively providing pressurized fluid to certain of the jacks, to extend the jacks and to level the vehicle. Each jack includes a spring urging it to retract, with fluid pressure supplied to the jack overcoming the force of the spring to cause extension of the jack. When it is desired to retract the jacks, the leveling arrangement opens the jacks to reservoir to allow the springs to retract the jacks and to expel fluid therefrom to the reservoir.
The invention provides a number of features which provide highly advantageous construction, operation and/or installation of the vehicle leveling system.
In accordance with one feature of the invention, fluid pressure from the pump is provided to a primary supply/return line. A series of secondary supply/return lines each extend between the primary supply/return line and one of the jacks. A supply/return control valve is disposed in each secondary supply/return line. Each supply/return control valve is movable between a first position providing communication between the primary supply/return line and one of the jacks, to provide supply or return flow of fluid through the secondary supply/return line and the supply/return control valve, and a second position cutting off communication between the primary supply/return line and the jack. A return line communicates between the primary supply/return line and the reservoir, and a return control valve is disposed in the return line. The return control valve is movable between a first position allowing return flow from the primary supply/return line to the reservoir, and a second position preventing return flow to the reservoir through the return line. This feature of the invention minimizes the number of valves required to provide extension and retraction of the legs, thus reducing the cost of the system and entailing less wiring to install the system. Vehicle leveling systems of which the applicants are aware employ a number of valves equally twice the number of jacks, to provide extension and retraction of the jacks. That is, known four-jack systems require eight valves, whereas known three-jack systems require six valves. In accordance with this aspect of the invention, a three-jack system requires four valves to extend and retract the jacks, whereas a four-jack system requires five valves.
In accordance with another feature of the invention, a bidirectional flow-control valve is located between each jack and the primary supply/return line, to provide slow retraction of the jacks until the vehicle wheels engage the ground, and to thereafter provide fast retraction of the jacks once the load on the jacks has been relieved by the vehicle wheels. This feature of the invention reduces the overall time required to retract the jacks.
In accordance with another feature of the invention, a low pressure switch is interconnected with the primary supply/return line for detecting a threshold pressure which indicates that all of the jacks have engaged the ground, and for thereafter commencing operation of the leveling arrangement to level the vehicle. In a preferred form, the primary supply/return line is a passage formed in a manifold, and the low pressure switch is mounted to the manifold so as to be in communication with the primary supply/return line passage to detect the low pressure threshold within the primary supply/return line passage. In addition, a high pressure switch is preferably mounted to the manifold so as to be in communication with the primary supply/return line passage. The high pressure switch is interconnected with the leveling arrangement to terminate its operation when a high pressure threshold is attained, such as occurs when one of the jacks is fully extended. Mounting of the low and high pressure switches directly to the manifold provides advantageous packaging of the manifold, valve and switch components.
In accordance with yet another feature of the invention, the reservoir comprises a tank, and the pump is located within the tank. A motor drives the pump, and the pump and motor are mounted to the tank through a mounting arrangement which includes a supply passage forming a portion of the supply line for providing supply of flow of fluid from the tank in response to operation of the pump, and a return passage forming a portion of the return line for providing return flow of fluid to the tank. The manifold, in which the primary supply/return line passage is formed, is adapted for direct mounting to the pump and motor mounting arrangement for establishing direct communication between the supply and return passages formed in the mounting arrangement and a supply and return passage, respectively, formed in the manifold, each of which is in communication with the primary supply/return line passage. The direct mounting of the valve manifold to the pump mounting arrangement eliminates the need for connecting hydraulic hoses between the valve manifold and the reservoir, and provides a clean assembly which can easily be installed on the vehicle frame.
In accordance with yet another feature of the invention, the tank includes an end wall and one or more side walls, which cooperate to form a corner. An intake tube extends from the pump into the tank for providing intake of fluid to the pump from an inlet, and a discharge tube extends from the pump into the tank for discharging fluid into the tank from an outlet. The intake tube inlet and the discharge tube outlet are located in close proximity to each other, and also in close proximity to the corner. With this arrangement, the tank can be mounted such that either the end wall or the side wall adjacent the corner defines the lowermost extent of the tank. This feature accommodates mounting of the tank to the vehicle frame such that a longitudinal axis of the tank is oriented either horizontally or vertically.
In accordance with another feature of the invention, the vehicle has a suspension which includes one or more inflatable and deflatable air bags and a source of pressurized air, and the invention includes a pneumatic control system for inflating and deflating the airbags. The vehicle suspension includes one or more air pressure supply valves interposed between the source of pressurized air and the air bags. Each supply valve is movable between a first position for supplying pressurized air to the air bags, and a second position for cutting off supply of pressurized air to the air bags. The pneumatic control system of the invention includes one or more relay valves located between each supply valve and the air bags. Each relay valve is movable between a first position establishing communication between a supply valve and one or more air bags, and a second position for exhausting air from one or more air bags. A control valve is provided for selectively moving the relay valves between their first and second positions. The control valve is interconnected with the leveling arrangement for moving the relay valves to their second position to exhaust the air bags prior to leveling of the vehicle, and for moving the relay valves to their first position to fill the air bags after retraction of the legs and prior to operation of the vehicle. The control valve is preferably an electrically operated valve disposed between the pressurized air source and each relay valve. The relay valves are movable between their first and second positions in response to supply of pressurized air, and the control valve is movable in response to the leveling arrangement between a first position for supplying pressurized air to each relay valve from the pressurized air source, and a second position for cutting off supply of pressurized air to the relay valves. This feature of the invention provides a single solenoid-operated control valve which selectively supplies air pressure to the relay valves, thus minimizing the electrical wiring involved in installing the pneumatic control system. In addition, the control valve maintains pressure within the pressurized air source, such as a pressurized air tank, even during and after exhaustion of the air bags.
In accordance with a further feature of the invention, each supply/return control valve is manually movable from its second position to its first position, as is the return control valve. This feature allows the operator to position the supply/return control valves and the return control valve so as to allow the jacks to retract due to operation of the spring associated with each jack, in the event of an electrical failure of the system. In addition, pneumatic control valve is manually operable so as to allow the air bags to be filled in the event of an electrical failure of the system.
In accordance with yet another feature of the invention, the leveling arrangement is interconnected with the transmission neutral switch and the parking brake switch. When the operator starts the vehicle engine while the jacks are extended and either the parking brake is disengaged or the transmission is taken out of neutral or park, the jacks are automatically retracted.
In accordance with a further feature of the invention, the front jacks are retracted before the rear jacks when the operator initiates retraction. This minimizes side loads which can be incurred due to the geometry of the vehicle suspension during lowering of the jacks. The front jacks are preferably retracted until the front wheels engage the ground and the front jack is lifted from the ground, before the rear jacks begin retraction.
In accordance with a further feature of the invention, the leveling arrangement is interconnected with a sensing system for sensing voltage across the pump motor, which is operated off the vehicle battery. In the event the vehicle battery voltage is low/ the current supplied to the pump from the battery will increase, and may cause damage to the pump. The sensing system senses if the voltage at the pump falls below a predetermined threshold, and operation of the leveling arrangement is terminated if the voltage at the pump motor is less than the predetermined threshold. When this occurs, the jacks can still be retracted to allow operation of the vehicle.
The features of the invention as summarized in the foregoing paragraphs may be employed separately or in various subcombinations in a vehicle leveling system. In a particularly preferred form of the invention, however, the features are combined in a single leveling system providing highly satisfactory construction, operation and/or installation.
Various other features, objects and advantages of the invention will be made apparent from the following description, taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate the best mode presently contemplated of carrying out the invention.
In the drawings:
FIG. 1 is a schematic bottom plan view of the vehicle leveling system of the invention installed on a vehicle, such as a recreational vehicle;
FIG. 2 is a hydraulic schematic of the vehicle leveling system of the invention;
FIG. 3 is an exploded isometric view of one of the extendable and retractable jacks employed in the vehicle leveling system of the invention;
FIG. 4 is an isometric view showing the layout of the hydraulic and pneumatic components of the vehicle leveling system of the invention adapted for installation on the vehicle frame;
FIG 5 is an exploded isometric view, with a portion broken away, showing the tank, pump and motor assembly and the valve manifold assembly of the vehicle leveling system of the invention;
FIG. 6 is a schematic representation of the pneumatic control system forming a part of the leveling system of the invention in combination with the vehicle pneumatic system;
FIG. 7 is an isometric view of the pneumatic control valve incorporated in the pneumatic control system shown in FIG. 6;
FIG. 8 is a schematic wiring diagram of the vehicle leveling system of the invention; and
FIG. 9 is a schematic block diagram of the control system for the vehicle leveling system of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates the underside of a recreational vehicle 10 having a pair of front tires 12 and two sets of rear tires, shown at 14, 15. A front axle 16 extends between front tires 12, and a rear axle 18 extends between rear tire sets 14, 15. Front axle 16 and rear axle 18 are mounted to the frame (not shown) of vehicle 10.
In accordance with the invention, a leveling system is mounted to the vehicle frame, and includes a level-sensing switch 20, a pair of rear jacks 22, 24, and a front jack 26. Rear jack 22 is located adjacent rear tire set 14, while rear jack 24 is located adjacent rear tire set 15. Front jack 26 is centrally located between front tires 12 adjacent front axle 16. As will be explained, switch 20 is interconnected with a controller and a hydraulic system (not shown in FIG. 1), to control extension and retraction of jacks 22-26, resulting in raising of vehicle 10 to level the vehicle and lowering of vehicle 10 to allow operation of the vehicle.
While the leveling system of the invention is shown in conjunction with a recreational vehicle, it is to be understood that the system is capable of providing leveling of any vehicle or other movable structure.
FIG. 2 schematically illustrates the hydraulic circuitry of the vehicle leveling system according to the invention. The hydraulic system of FIG. 2 is interconnected with jacks 22-26, and reference is made to jack 22 in FIGS. 2 and 3 for a brief description of its construction, with the understanding that jacks 24 and 26 are constructed identically to jack 22.
Referring to FIGS. 2 and 3, jack 22 generally comprises a cylinder 27 adapted to be mounted to the vehicle frame, with a piston 28 (FIG. 2) mounted for reciprocable sliding movement within cylinder 27. A rod 29 (FIG. 2) is connected to the underside of piston 28, and a foot or shoe 30 (FIGS. 2, 3) is mounted to the opposite end of rod 29. Rod 29 is interconnected with a spring 31 (FIG. 2) located in the interior of cylinder 27, for urging piston 28 upwardly and thereby urging retraction of rod 29. Cylinder 27 defines an upper chamber 32 above piston 28, to which fluid is supplied or expelled through a line 33 (FIG. 2) and a fitting 33a (FIG. 3).
Referring to FIG. 3, jack 22 includes a mounting bracket 34 connected to cylinder 27, through which jack 22 is mounted to the frame of vehicle 10. A trip rod housing 35 is mounted to the side of cylinder 27 opposite bracket 34, and a trip rod 36 is adapted for placement within trip rod housing 35. A reed switch 37 is mounted above the upper end of trip rod 36, and a spring 38 is placed between reed switch 37 and the upper end of trip rod 36 to bias them away from each other. A cable 39 extends from reed switch 37. Reed switch 37 is fixed in position by a plate 40, adapted for connection to the upper end of cylinder 27.
The lower end of trip rod 36 is engaged by the upper surface of shoe 34 when jack 22 is fully retracted, to move the upper end of trip rod 36 into engagement with reed switch 37. This closes reed switch 37, to provide a signal through cable 39 that jack 22 is fully retracted. When extension of jack 22 is commenced and jack 22 is moved away from its fully retracted position, the upper surface of shoe 34 disengages the lower end of trip rod 36 and the upper end of trip rod 36 is moved away from reed switch 37 by the action of spring 38. This opens reed switch 37, to provide a signal through cable 39 that jack 22 is extended.
The internal construction of jacks 22, 24 and 26 may generally be shown and described in co-pending application Ser. No. 07/758,278 filed Aug. 27, 1991, which is a continuation of application Ser. No. 07/327,539 filed Mar. 23, 1989, the disclosure of which is hereby incorporated by reference, with particular reference being made to FIG. 3 of such application.
As noted, jacks 24 and 26 are substantially identical in construction and operation to jack 22. Referring to FIG. 2, fluid is supplied to or expelled from jacks 24 and 26 through lines 42 and 44, respectively.
As shown in FIG. 2, lines 32, 42 and 44 extend between a valve manifold 46 and jacks 22, 24 and 26, respectively. Manifold 46 is mounted to a pump and reservoir assembly, shown generally at 48.
A primary supply/return passage 50 is formed in valve manifold 46, extending inwardly from a port 52 formed in a side of manifold 46. A secondary supply/return passage 54 extends between primary supply/return passage 50 and a port 56, to which line 32 is connected. A secondary supply/return passage 58 extends between primary supply/return passage 50 and a port 60 to which line 42 is connected, and a secondary supply/return passage 62 extends between primary supply/return passage 50 and a port 64 to which line 44 is connected.
Referring still to FIG. 2, identical supply/return control valves 66, 68 and 70 are located in secondary supply/return lines 54, 58 and 62, respectively. Supply/return control valves 66-70 are solenoid operated dual poppet bidirectional blocking valves, with a manual override, such as manufactured by Delta under its Part No. 86020151.
Valves 66-70 each include a rightward block having a double check valve and a leftward block providing free flow therethrough. Valves 66-70 are biased toward their position shown in FIG. 2, in which their rightward blocks are located in secondary supply/return lines 54-62, respectively. In accordance with known construction, valves 66-70 are shiftable rightwardly in response to supply of electrical current to a solenoid. In the event of an electrical failure, valves 66-70 can be manually shifted between their rightward and leftward positions.
When supply/return control valve 66 is in its FIG. 2 position, fluid communication between primary supply/return passage 50 and jack 22 is cut off by means of the double check valve arrangement of valve 66. Similarly, valves 68 and 70 cut off communication between primary supply/return passage 50 and jacks 24 and 26, respectively, when in their FIG. 2 position.
When supply/return control valve 66 is shifted rightwardly, communication is established between primary supply/return passage 50 and jack 22. Similarly, shifting of supply/return control valves 68 and 70 rightwardly results in communication between primary supply/return passage 50 and jacks 24 and 26, respectively.
A retraction restricting valve 72 is located in secondary supply/return passage 54, between supply/return control valve 66 and port 56. Similarly, retraction restricting valves 74 and 76 are located between supply/return control valves 68, 70 and ports 60, 64, respectively.
Retraction restricting valves 72-76 are generally constructed in accordance with the teachings of Schneider U.S. Pat. No. 4,704,947 entitled "BIDIRECTIONAL FLUID FLOW VALVE, owned by the same assignee as the present application, and the disclosure of which is hereby incorporated by reference. Valves 72, 74 and 76 provide unrestricted flow in lines 54, 58 and 62, respectively, during supply of pressurized fluid from primary supply/return passage 50 to jacks 22-26, respectively, to extend jacks 22-26. On the other hand, when fluid pressure in primary supply/return passage 50 is relieved and flow control valves 66-70 are shifted rightwardly to provide retraction of jacks 22-26, respectively, retraction restricting valves 72-76 are shifted to provide a restriction in the return flow of fluid from jacks 22-26, respectively, to primary supply/return passage 50, until pressure on jacks 22-24 is relieved to a predetermined extent. In this application, retraction restricting valve 76 is shifted to provide slow retraction of front jack 26 until front wheels 12 engage the ground and relieve pressure on jack 26. When this occurs, retraction restricting valve 72 is shifted to its FIG. 2 position to eliminate the restriction in flow through valve 72 and to provide full flow of fluid there-across in secondary supply/return line 54, to provide fast retraction of jack 22. In a similar manner, retraction restricting valve 74 provides slow retraction of jack 24 until rear tire set 15 engages the ground, and thereafter fast retraction, and retraction restricting valve 76 provides slow retraction of jack 26 until rear tire set 14 engages the ground, and thereafter fast retraction.
A supply passage 78 is formed in valve manifold 46 between primary supply/return passage 50 and a port 80. A check valve 82 is disposed within supply passage 78 between port 80 and primary supply/return passage 50, providing one-way flow of fluid from port 80 to primary supply/return passage 50. A return passage 84 extends between primary supply/return passage 50 and a port 86. A return control valve 88 is located in return passage 84 between port 80 and primary supply/return passage 50.
Return control valve 88 is a two-way normally closed solenoid operated poppet valve, such as is sold by Delta under its Part No. 85002351. Return control valve 88 provides a rightward block having a check valve which prevents fluid flow from primary supply/return passage 50 through return passage 84 to port 86, and a leftward block having an oppositely oriented check valve which allows flow in return passage 84 from primary supply/return passage to port 86. Return control valve 88 is biased to its FIG. 2 position in which its rightward block is disposed in return passage 84. The leftward block of return valve 88 provides an alternate flow path restricting arrangement, which in this application is not used.
Pump and reservoir assembly 48 includes a reservoir 90 for containing a quantity of hydraulic fluid. An intake line 92 is located within reservoir 90, as is a discharge line 94. A pump 96 draws hydraulic fluid from reservoir 90 through intake line 92, and a pump motor 98 provides operation of pump 96. Pump 96 supplies fluid under pressure to a supply passage 100, which is connected to port 80 for supplying pressurized fluid to valve manifold supply passage 78 in response to operation of pump 96.
Discharge line 94 is connected to port 86 and thereby to return passage 84, for returning hydraulic fluid to reservoir 90 when return control valve 88 is shifted rightwardly.
A high pressure relief valve 102 is located in a line 104 spanning between supply passage 100 and discharge line 94.
Referring still to FIG. 2, a low pressure switch 106 is mounted to valve manifold 46 at port 52, so as to be in communication therethrough with primary supply/return passage 50. Similarly, a high pressure switch 108 is mounted to valve manifold 46 at a port 110, which communicates through a passage 112 with primary supply/return passage 50. Low pressure switch 106 is set to be actuated when a relatively low threshold of pressure, e.g. 350 psi, is experienced in primary supply/return passage 50. High pressure switch 108, on the other hand, is set to be actuated when a relatively high threshold of pressure, e.g. 2400 psi, is experienced in primary supply/return passage 50. As will be explained, low pressure switch 106 is actuated when jacks 22-26 are lowered so as to engage the ground, to commence the leveling operation. High pressure switch 108 is actuated when one of jacks 22-26 is fully extended, such as when vehicle 10 is parked on an excessive slope or one of jacks 22-26 is located over a depression or the like in the ground.
FIG. 5 illustrates valve manifold 46 and pump and reservoir assembly 48 in detail, as illustrated schematically in FIG. 2, and like reference characters will be used where possible to facilitate clarity.
Referring to FIG. 5 reservoir 90 is in the form of a tank having a pair of end walls 114, 116, with side walls 118, 120, 122 and 124 extending between end walls 114, 116. Pump 96 is mounted to end wall 116, and an adaptor plate 126 is mounted to the upper end of pump 96. Pump motor 98 is connected to adaptor plate 126.
Intake line 92 defines an inlet opening 128, through which fluid within reservoir 90 is supplied to pump 96 upon its operation. Discharge line 94 defines an outlet opening 130 for discharging hydraulic fluid into reservoir 90.
Intake line 92 and discharge line 94 are oriented in the interior of reservoir 90 such that inlet opening 128 and outlet opening 130 are located in close proximity to the corner defined by end wall 114 in combination with side wall 120, closely adjacent the lower end of side wall 120. With this construction of pump and reservoir assembly 48, it is possible to mount assembly 48 such that its longitudinal axis is disposed either horizontally or vertically. That is, assembly 48 can be mounted vertically as shown in FIG. 3, with end wall 114 defining the lowermost surface of reservoir 90, or along a horizontal axis in which side wall 118 defines the lowermost surface of reservoir 90. In either event, the location of inlet opening 128 and discharge opening 130 adjacent the corner defined by end wall 114 in combination with side wall 120 ensures that intake line 92 and discharge line 94 provide intake and discharge, respectively, of hydraulic fluid from or to the bottom of reservoir 90. Essentially, a line defined by the intersection of end wall 114 with side wall 120 defines an axis about which pump and reservoir assembly 48 can be pivoted to accommodate either vertical or horizontal mounting to the frame of vehicle 10.
Referring still to FIG. 5, operation of pump 96 provides hydraulic fluid under pressure to a supply port 132, and supply passage 100 (FIG. 2) extends inwardly into adaptor plate 126 from supply port 132. Similarly, a return port 134 is formed in adaptor plate 126, and communicates through a return passage formed therein with discharge line 94. Valve manifold 46 is mounted to adaptor plate 126 such that supply port 80 (FIG. 2) and return port 86 (FIG. 2), formed in the rear surface of valve manifold 46, are placed in communication with supply port 132 and return port 134, respectively, formed in adaptor plate 126. A pair of threaded socket head screws 136 extend through openings 138 formed in valve manifold 46 and into threaded openings 140 formed in the side surface of adaptor plate 126, to mount valve manifold 46 to adaptor plate 126.
O-rings 142 are placed between the rear surface of valve manifold 46 and the side surface of adaptor plate 126 to provide a fluid-tight seal between supply ports 80, 132 and return ports 86, 134 formed in valve manifold 46 and adaptor plate 126, respectively.
Referring still to FIG. 5, supply/return control valves 66, 68 and 70 comprise cartridges mounted to the front surface of valve manifold 46. Electrical prongs extends from each of valves 66-70 for providing an electrical connection thereto to control of the solenoid associated with valves 66-70. A series of 90° elbows 144, 146 and 148 are mounted to valve manifold 46 at ports 56, 60 and 64 (FIG. 2), respectively, in the upper end of vertical passages which comprise secondary supply/return passages 54, 58 and 62 formed in valve manifold 46. Each elbow 144-148 includes a nipple adapted to receive one end of a hydraulic line, the other end of which is connectable to one of jacks 22-26. Retraction restricting valves are placed within the vertical passages formed in valve manifold 46, between elbows 144-148 and supply/return control valves 66-70.
Return control valve 88 is similarly in the form of a cartridge mounted to the front surface of valve manifold 46, for controlling return flow of hydraulic fluid to return port 134. The cartridge comprising return control valve 88 further includes electrical connectors for operating the solenoid associated with valve 88, in a manner similar to valves 66-70.
Low-pressure switch 106 and high-pressure switch 108 are mounted in ports 52, 110, respectively, formed in the lower surface of valve manifold 46. Switches 106, 108 each include electrical connectors for interconnection with the leveling system, as will be explained.
The cartridges which comprise supply/return control valves 66-70, and return control valve 88, each include a knurled end knob 150 which allows an operator to manually shift valves 66-70 and 88 in the event of an electrical failure, wherein supply of electricity to the solenoids of valves 66-70 and 88 is cut off. As will be explained, this allows jacks 22-26 to be retracted in the event they are extended when an electrical failure occurs.
FIG. 6 schematically illustrates the pneumatic system of vehicle 10 having a suspension which includes a series of air bags, such as shown at 152, 154, 156 and 158, located one adjacent the location of each of the vehicle wheels. The vehicle further includes an air reservoir 160 containing a supply of pressurized air, furnished by an air compressor (not shown) as is known in the art. The vehicle suspension includes a rear air bag height valve 162, a front right air bag height valve 164, and a front left air bag height valve 166. Height valves 162-166 are supplied with the vehicle suspension, and in normal operation selectively supply pressurized air to bags 152-158, or exhaust air therefrom, in order to maintain a predetermined height between the axles and the vehicle frame. A line 168 extends between air tank 160 and height valve 162, and a line 170 tees into line 168 and is interconnected with height valves 164 and 166 through lines 172, 174, respectively. A line 176 extends between height valve 162 and a pair of lines 178, 180, which extend to air bags 152, 154, respectively.
The components of the pneumatic system described to this point are typically furnished with the vehicle, and the construction and operation of such components is known in the art.
In accordance with the invention, a relay valve 182 is connected in line 176 between height valve 162 and lines 178, 180. Similarly, a relay valve 186 is connected in a line 188 extending between height valve 164 and air bag 156, and a relay valve 190 is connected in a line 192 extending between height valve 166 and air bag 158. Relay valves 182, 186 and 190 are pilot operated air relay valves such as are available from Humphrey under Part No. P1103. Relay valves 182, 186 and 190 are spring biased to their positions as shown in FIG. 6, establishing communication in lines 176, 188 and 192, respectively. In response to the supply of pilot air pressure, relay valve 182 is shiftable leftwardly so as to cut off communication between height valve 162 and lines 178, 180, and establishing a vent to atmosphere of line 176 to exhaust air bags 152 and 154. Similarly, shifting of relay valve 186 leftwardly cuts off communication of height valve 164 with air bag 156, and air bag 156 is exposed to atmosphere through relay valve 186. Relay valve 190, when shifted leftwardly, cuts off communication of height valve 166 with air bag 158, and opens air bag 158 to atmosphere so as to exhaust air bag 158.
A pneumatic control valve 194 is interconnected with line 168 through a line 196, so as to be exposed to pressurized air within air tank 160. A line 198 provides communication between control valve 194 and the pilot end of relay valve 182. A line 200 communicates between line 198 and the pilot end of relay valve 190, and a line 202 communicates between line 200 and the pilot end of relay valve 186.
Control valve 194 is a double acting solenoid operated valve, with manual override, such as manufactured by Norgren under its designation "NUGGET 200", Part No. K41DA00-K1L-K1L.- Control valve 194 is normally in its position as shown in FIG. 6, in which communication between lines 196 and 198 is cut off. When control valve 194 is in this position, relay valves 182, 186 and 190 provide nothing more than conduits for passage of air between the air bags and the height valves. When it is desired to commence leveling by extending jacks 22-26, in a manner to be explained, control valve 194 is shifted leftwardly so as to establish communication between lines 196 and 198. When this occurs, the pilot ends of relay valves 182, 186 and 190 are exposed to air pressure from air tank 160 through control valve 194. Air bags 152 and 154 are exhausted through relay valve 182, while air bags 156 and 158 are exhausted through relay valves 186 and 190, respectively. Pressurized air is maintained within air tank 160 and the lines interconnecting air tank 160 with height valves 162-166 when air bags 152-158 are exhausted. When it is again desired to operate vehicle 10, control valve 194 is shifted rightwardly so as to cut off the supply of pressurized air to relay valves 182, 186 and 190, to recharge air bags 152-158 from air tank 160 prior to operation of vehicle 10. In contrast with prior art systems, which dumped the entire supply of pressurized air from the air bags and the air reservoir, the present invention provides a system which exhausts only the air bags, and which accordingly takes less time to recharge the air bags since it is not necessary to recharge the air tank as well.
FIG. 7 illustrates a physical embodiment of pneumatic control valve 194. Generally, control valve 94 includes a valve body 204 to which lines 196 and 198 are connected. The solenoids which provide shifting movement of control valve 94 each include electrical inputs 206, 208, which are interconnected with the vehicle leveling system in a manner as will be described. A manual override knob 208 is provided for selectively shifting control valve 194 to its position as shown in FIG. 6, which allows air bags 152-158 to be filled from air pressure within air tank 160 even in the event of an electrical failure which prevents operation of the solenoids associated with control valve 194. This allows vehicle 10 to be operated even in the event of such an electrical failure.
FIG. 8 schematically illustrates the electrical wiring connections involved with the leveling system components as shown as described with respect to FIGS. 1-7. As shown in FIG. 8, a pair of wires extend from each of jacks 22-26. Such wires are interconnected with the limit reed switches associated with jacks 22-26 for providing a signal when jacks 22-26 begin extension and are moved away from their fully retracted position.
A pair of wires are interconnected with each of valves 66-70 and 88 mounted to valve manifold 46, for controlling operation of the solenoids of valves 66-70 and 88. A pair of wires are also interconnected with each of low and high pressure switches 106, 108, for providing a signal in response to detection of low or high pressure, respectively, within valve manifold 46.
The vehicle battery, shown at 210, is interconnected with the starting solenoid, shown at 212, of pump motor 98. A pair of wires 214, 216 are connected across solenoid 212 for sensing voltage at solenoid 212, which reflects voltage supplied thereto from vehicle battery 210. As will be explained, when the voltage at solenoid 212 drops below a predetermined level, operation of the leveling system is terminated. As is known, when voltage supplied to solenoid 212 from vehicle battery 210 drops, the current supplied to solenoid 212 necessarily increases, which may result in burning out of pump motor 98. Detecting low voltage at solenoid 212 and shutting down the leveling system in response thereto, prevents damage to pump 98 in response to such an increase in current.
Level-sensing switch 20 is wired into a microprocessor control box, shown generally at 216, as are the wires associated with jacks 22-26, valves 66-70 and 88, low and high pressure switches 106, 108, solenoid 212 and pump motor 98. In addition, wires from the solenoids associated with air control valve 194 are wired into microprocessor control box 216.
A wire 218 is interconnected with an oil pressure indicator terminal 220 associated with the vehicle's junction box, shown at 222. A wire 224 extends from the neutral safety switch terminal 226 of junction box 222. A pair of wires 228, 230 extend from the switch bank of the vehicle's circuit breaker panel, shown at 232. In addition, a wire 234 is interconnected with a "jacks down" indicator light 236 from circuit breaker panel 232, and is interconnected with microprocessor control box 216 for providing a visual indication when any of jacks 22, 24 or 26 is moved away from its fully retracted position in response to opening of a reed switch, such as 37 (FIG. 3) associated with one of the jacks.
In addition, the vehicle's parking brake switch, shown at 238, is connected via a wire 240 to microprocessor control box 216, for providing a signal in response to engagement or disengagement of parking brake switch 238.
Microprocessor control box 216 is wired into a control panel 242, which is located within the interior of vehicle 10.
Control panel 242, in a typical system, includes an ON/OFF switch 244, an automatic retract switch 246 and an automatic level switch 248. In addition, control panel 242 includes an indicator light 250 for providing an indication of excess slope, an indicator light 252 for providing an indication that the system is level, an indicator light 254 for providing an indication that the system is retracted, and an indicator light 256 for providing an indication that the system requires checking.
FIG. 9 represents a block diagram of the main logic schematic of microprocessor control box 216 which, in accordance with known microprocessor technology, provides operation of the vehicle levelling system of the invention in response to operator input and various conditions as sensed by various components of the system.
FIG. 9 illustrates in block form the microprocessor control system for controlling the vehicle leveling system of the invention. The control system includes a central microprocessor 260 which includes timers and clock oscillator circuitry. Processor 260 may be a processor such as is available from Motorola under its designation MC68705R3S, which is an 8 bit processor including Random Access Memory (RAM) and Programmable Read-Only Memory (PROM). The control system includes a power conditioning block 262 connected to the vehicle battery for providing power to the control system. Power conditioning block 262 includes components which provide reverse polarity protection, transient conditioning, bulk filtering and voltage regulation for a logic circuit associated therewith.
An analog input conditioning block 264 is connected to power conditioning block 264 via a bus 266, to enable detection of low voltage situations prior to loss of logic voltage from the logic circuitry of power conditioning block 262, to avert situations in which the logic circuitry of power conditioning block 262 fails to execute code in a proper manner.
The control system further includes a reset control block 268 which consists of a voltage reference, an RC filter having a rapid discharge, and a comparator. The output of the comparator of block 268 applies a reset stimulus to central processor 260 for a predetermined amount of time during initial power application, to allow the processor clock to stabilize before attempting to execute operational code. Reduction of the regulated logic voltage below a known safe operating point is also detected by a comparison of the proportioned logic power voltage applied to a pin of the comparator, and the reference voltage applied to a different pin of the comparator. Unsafe low logic power voltage levels will cause the comparator of reset control block 262 to reset processor 260, and hold the reset stimulus on the processor until the low voltage condition has been corrected.
A watchdog circuit 270, which includes a microprocessor of its own, consists of a dual retriggerable one-shot circuit with timing components connected thereon, a trigger (retrigger) input and a decoder with outputs to an interrupt input of processor 260. Watchdog circuit block 270 detects abnormalities in processing and interrupts the execution of improper code. Such abnormalities can be caused by alteration, over time, of programmed values in the RAM operational program, or by errors in reading the programmed values caused by energetic transients impressed upon the processor bus or address lines. The output of watchdog circuit block 270 also is used as an absolute override to all output drivers, to reset the drivers to their OFF state regardless of instructions (outputs) provided by processor 260.
The control system further includes a switch input conditioning block 272 and an analog input conditioning block 274. The circuitry in analog input conditioning block 274 provides an alternative path for excess voltage of either polarity, to prevent damaging levels of voltage from existing at the analog input pins of processor 260. In addition, analog input conditioning block 274 provides for scaling of the input voltages by resistor proportions, in a manner as is known. Switch input conditioning block 272 provides "noise" filtering, transient clipping, and buffering of all of the switch inputs to processor 260, namely input from low pressure switch 106, high pressure switch 108, oil pressure terminal 220, neutral switch 226, parking brake switch 238 and circuit breaker panel 232. In addition, switch input conditioning block 272 includes "pull-up" resistors for ground true switches and "pull-down" resistors for vehicle voltage true state switches. The "pull-up" and pull-down" resistors minimize ambiguities caused by failures in the external circuitry which may also be connected to the switch contacts being used as inputs to switch input conditioning block 272.
The control system further includes a switch input conditioning and multiplexing block 274, which provides the same basic filtering and transient conditioning as switch input conditioning block 272, but includes a complex buffer multiplexer circuit. In a manner as is known, input/output requirements which exceed the capacity of the port structure of processor 260, are resolved by multiplexing two or more signals to each pin of a processor port. Block 274 provides for inputting of eight switch signals into four port pins.
The control system further includes a keypad scanning block 274. Keypad scanning block 274 includes a latch circuit microprocessor, the output of which is buffered by another microprocessor to activate a row of switches, including switches 244, 246 and 248, in the matrix of control panel 242. If one of switches 244-248 is "true", i.e. activated, the associated column line changes to the active state and is detected by the processor of keypad scanning block 276 via digital states on certain ports of the keypad scanning microprocessor. The row and column lines are "buffered" to protect the processor and other circuitry of keypad scanning block 276 from transient discharge damage. Keypad scanning block 276 further provides capabilities for up to four rows and four columns of a keypad, i.e. a 16-key matrix keypad. In the application of the present invention, however, only three switches, namely switches 244-248 are employed. Keypad scanning block 8 is interconnected with watchdog circuit block 270.
The control system further includes an output latch/driver block 280, which consists of a series of complex integrated circuits which can "decode" and "latch" the processor commanded state into a selected output. Each driver circuit includes a clearing function which is capable of positively turning off all outputs of the integrated circuits, and is connected to watchdog circuit block 270. The outputs of one of the integrated circuits of output latch/driver block 280 are directed to a power switch block 282.
Power switch block 282 includes a series of identical power switches each including a high power transistor, a current sampling resistor, and circuitry responding thereto which can be triggered ON to bypass the base driver to the power transistor if the current through the sampling resistor exceeds a predetermined level. The bypassing circuitry will RESET whenever the base drive for the power transistor is removed. The power switches are self-resetting, overload protected, high side drivers with integral fast recovery fly back diodes. Each individual power switch is interconnected with one of the solenoids to control the various components of the leveling system of the invention, namely the solenoids of supply/return control valves 66-70, return control valve 88, the two solenoids associated with pneumatic control valve 194, and solenoid 212 of pump motor 98.
Finally, the control system includes an emergency STOP/INTERRUPT block 284 which interfaces a separate optional operator-controlled emergency stop push button to a port on processor 260, which is programmed as an interrupt. Processor 260 is programmed so as to be responsible for monitoring interrupt status and control to ensure proper conditioning and response to the interrupt input.
Submitted as an appendix with this application is a print showing detailed circuitry for the control system block diagram of FIG. 9, which embodies the best mode presently known of carrying out the control system of the invention. It is believed the components shown in the appendix, and their interconnection and operation, will be apparent to one skilled in the art.
The leveling system, including the control system of FIG. 9 and its microprocessors, including central processor 260, is programmed to operate in the following manner.
Central processor 260 operates when the ignition system of vehicle 10 is turned on. When it is not desired to level the vehicle, the operator places ON/OFF switch 244 in its OFF condition. Indicator light 236 will display if any of jacks 22-26 are not completely retracted, responsive to the reed switch associated with each jack.
When it is desired to operate the leveling system, the operator places ON/OFF switch 244 in its ON condition. This can be done either to level the vehicle or to check the status of the vehicle leveling system, e.g. whether all of the jacks are retracted or whether the vehicle is level or has shifted and is no longer level. When the vehicle engine is running and jacks 22-26 are up, pneumatic control valve 194 is in its FIG. 6 position, allowing air pressure to be supplied to air bags 152-158.
To level the vehicle, the operator actuates automatic level switch 248, and an LED associated with switch 248 is illuminated. If desired, the backup alarm of the vehicle may be wired into the leveling system so as to activate the alarm for the duration of the automatic leveling sequence. Processor 260 is programmed so as to wait for a period of approximately five seconds before beginning extension of jacks 22-26. Processor 260 then outputs a signal to commence extension of jacks 22-26 in response to energizing the solenoids of supply/return control valves 66-70, to move valves 66-70 to a position allowing supply of pressurized fluid from primary supply/return passage 50 to secondary supply/return passages 54, 58 and 62. When jacks 22-26 are moved away from their fully retracted position off of the reed switch associated with each jack, processor 60 provides a signal to one of the solenoids of pneumatic control valve 194, to provide air pressure to relay valves 182, 186 and 190 so as to exhaust air bags 152-158. In a preferred form, pneumatic control valve 194 is pulsed for approximately five seconds to ensure that air bags 152-158 are fully exhausted. If the reed switch of any of jacks 22-26 is not cleared or disengaged, in one second, the automatic leveling sequence is aborted and the SYSTEM CHECK indicator 256 is illuminated. If desired, an audible alarm may also be activated to alert the operator to this condition.
Once jacks 22-24 are extended to the ground, low pressure switch 106 provides a signal to processor 260 that the low pressure threshold has been attained. Processor 260 continues extension of jacks 22-26 for approximately one second after low pressure is indicated, then pump 96 and motor 98 are shut off and supply/return control valves 66-70 are returned to their closed condition, to terminate extension of jacks 22-26.
If all of jacks 22-26 indicate the presence of low pressure in primary supply/return passage 50 without the presence of high pressure, then the leveling sequence takes place. Processor 260 checks the inputs of level-sensing switch 20 in the order of front, back, left then right. If any input to processor 20 provides a non-level signal, processor 260 provides a signal to the appropriate one of jacks 22-26 to level the vehicle. If the front of the vehicle is low, then front jack 26 is extended. If the rear of the vehicle is low, both rear jacks 22 and 24 are extended. If the left side of the vehicle is low, left rear jack 22 is extended. If the right side of the vehicle is low, right rear jack 24 is extended. When the input of level-sensing switch 20 indicates that the sensed portion of the vehicle has been leveled, processor 260 moves onto the next input from level-sensing switch 20 to repeat the leveling sequence until all inputs from level-sensing switch 20 indicate a level condition. The output of level-sensing switch 20 must be constant for a period of time, e.g. approximately two seconds, before SYSTEM LEVEL indicator 252 is illuminated.
If, during extension of jacks 22-26, high pressure switch 108 is actuated for over 0.50 seconds, and level-sensing switch 20 continues to supply a "low" indication, processor 260 aborts the automatic leveling sequence and provides a signal illuminating the EXCESS SLOPE indicator 250. The operator then must move vehicle 10 to a different location to try the leveling sequence over.
When the leveling sequence is completed and the output of level-sensing switch 20 is constant, processor 260 then tests each of jacks 22-26 individually to ensure that all jacks are on the ground. To do this, supply/return control valves 66-68 are actuated in turn for approximately 0.30 seconds, with a delay of approximately two seconds between such testing of each jack. After extending each jack in this manner, processor 260 reads low pressure switch 106 and high pressure switch 108. If low pressure is not indicated by low pressure switch 106, then the jack is not on the ground. On the other hand, if low pressure is indicated by low pressure switch 106, then the jack is satisfactorily on the ground. If both high and low pressure are indicated by switches 106, 108, then the jack is fully extended and probably not on the ground, and to be safe processor 260 is programmed to assume that the jack is not on the ground.
If processor 260 determines that all jacks are on the ground, it then waits until the outputs from level-sensing switch 20 are constant for a period of two seconds, and activates the SYSTEM LEVEL indicator 252.
If processor 260 determines that one of the jacks is not on the ground, then that jack is extended until low pressure switch 106 detects the presence of low pressure in supply/return passage 50, to determine if the jack is fully extended. If a jack is fully extended and not on the ground, then processor 260 provides a signal to illuminate EXCESS SLOPE indicator 250 and aborts the automatic leveling sequence.
After vehicle 10 has been leveled as outlined above and jacks 22-26 have been tested, and if vehicle 10 thereafter comes out of level for a period of more than two seconds, then processor 260 deactivates SYSTEM LEVEL indicator 250 and relevels vehicle 10 as outlined above, and the individual jacks are then retested.
In the event the automatic leveling sequence is aborted, processor 260 deactivates the visual indicator associated with the automatic leveling switch 248, and at the same time cuts off power to pump motor 98 and moves supply/return control valves 66-70 to their closed position. To retract jacks 22-26, the operator actuates automatic retract switch 246, and a visual indicator associated with switch 246 is illuminated. If desired, the system may activate the backup alarm of the vehicle, which can then remain on during the duration of the automatic retracting sequence. After automatic retract switch 246 is actuated, processor 260 waits for approximately five seconds, and then moves return control valve 88 to its position allowing flow in return passage 84 and return line 94. Supply/return control valve 70 is then shifted to allow flow in secondary supply/return line 62, to retract front jack 26. At the same time, pneumatic control valve 194 is shifted to its FIG. 6 position, to fill air bags 152-158. In addition, processor 260 begins a 15 second delay timer. When the 15 seconds is up, or when front jack 26 is moved to its fully retracted position as indicated by the reed switch associated therewith, whichever is sooner, processor 260 then provides a signal to supply/return control valves 66, 68 to shift them to a position allowing return flow in secondary supply/return passages 54, 58, to retract rear jacks 22-24. Processor 260 then waits for jacks 22-26 to completely retract. If this does not occur within five minutes, processor 260 provides a signal to illuminate SYSTEM CHECK indicator 256, and simultaneously operates an audible alarm and aborts the automatic retract sequence.
When the automatic retract sequence is aborted, return control valve 88 is shifted back to its FIG. 2 position to prevent return flow of fluid in return passage 84, and supply/return control valves 66-70 are also moved to their closed FIG. 2 position. The automatic retract visual indicator of switch 246 is deactivated.
When jacks 22-26 are completely retracted, supply/return control valves 66-70 and return control valve 88 are maintained open for approximately five seconds, and the SYSTEM RETRACT visual indicator 254 is illuminated to indicate that all jacks are fully retracted, and the automatic retracting sequence is aborted.
In the event the vehicle transmission is taken out of neutral or the vehicle's parking brake is disengaged, processor 260 receives a signal indicating either of these conditions. If the vehicle engine is not running, the signal indicating that the vehicle is out of neutral will be ignored by processor 260. If either the parking brake is disengaged, or the transmission is out of neutral and the vehicle engine is running, and any of jacks 22-26 are not fully retracted for a period of time of more than 0.50 seconds, then an emergency condition is identified by processor 260. When this occurs, processor 260 provides a signal to sound an audible alarm, and provides an intermittent flashing signal to "jacks down" indicator 236, which is located on the vehicle dashboard. At the same time, corresponding warning lights on control panel 242 are flashed. If the leveling system is not already turned on, processor 260 does so, and if the vehicle engine is running immediately begins the automatic retracting sequence to retract jacks 22-26. If the automatic emergency retracting sequence is started and thereafter the vehicle engine stops running, the automatic retracting sequence will continue. During this emergency state, ON/OFF switch 244 on control panel 242 is disabled.
Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention. | A system for leveling a vehicle, such as a recreational vehicle, includes three extendable and retractable fluid-operated jacks. The jacks are spring-biased to their retracted position. Supply of hydraulic fluid under pressure extends the jacks, and the jacks are retracted by relieving the supply of hydraulic fluid pressure to the jacks to allow the springs to expel fluid from the jacks. A number of unique aspects are incorporated in the leveling system for providing highly advantageous construction, operation and installation. | 1 |
FIELD OF THE INVENTION
The present invention pertains in general to a sewing operation with a sewing machine driving both a needle, and an upper and/or lower feed means for feeding the fabric to be sewn, and specifically to a sewing operation for forming satisfactory initial stitches.
BACKGROUND OF THE INVENTION
In a sewing machine equipped with a needle oscillating in the direction of feed, the needle plate has a stitch hole designed as a slot. This stitch slot extends in the direction of feed. As a consequence of this, the interlock of the initial stitches, especially of the first stitch, will come undone due to the lack of friction between the threads at the edge of the stitch slot on the pulling by the thread lever, and satisfactory stitches will be prevented from forming. This happens mainly in the case of short thread ends after a thread cutting operation.
SUMMARY AND OBJECTS OF THE INVENTION
The object of the present invention is to provide a process in a sewing machine with needle feed which guarantees reliable stitch formation at the beginning of a new sewing operation.
This is accomplished in a process where the needle is displaced into an end zone of the stitch hole of the needle plate prior to the sewing operation. A preselected number of initial stitches are then formed in this position of the needle. The displacement of the needle is then abolished, and the feed motion of the fabric being sewn is corrected by the amount of the displacement.
The process according to the present invention makes it possible to substantially improve conditions for stitch formation at the very beginning of the seam formation by the sufficient clamping effect of the threads at the edge of the stitch slot and thereby to achieve reliable initial stitch formation.
An advantageous feature of the invention is that during the initial stitches, the needle can perform a feed motion corresponding to the feed motion of the fabric. The feed motion of the fabric being brought about by upper and lower feed means.
The process according to the invention can also be designed so that the needle is stopped in its displaced position during the initial stitching and the entire feed motion of the fabric is performed by the feed means only during the phase in which the needle is withdrawn from the fabric. After the axis of the needle returns to its normal position, the needle can be moved allowing feeding for the fabric both when the needle has penetrated the fabric and when it has been withdrawn. This feature allows both the entry and the exit of the needle into and from the fabric being sewn to take place in the immediate end zone of the stitch slot. As a result of which optimal clamping conditions are created for the free thread ends at the edge of the stitch slot.
It is also possible to have the feed motion turned off during the first stitch, causing a reduction of thread consumption during the first stitch formation and consequently a reduction of after pulling of the sewing threads through the thread lever.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a synoptic, partially cut-away view of a sewing machine equipped with a needle feed mechanism;
FIG. 2 is an enlarged, partially cut-away side view of the sewing machine according to FIG. 1;
FIG. 3 is a sectional view along line III--III in FIG. 2;
FIG. 4 is a partially cut-away rear view of the stepping motor drive for swinging out the needle bar;
FIG. 5 is a block diagram of the electronic circuitry for the feed mechanism;
FIG. 6 is an enlarged sectional view through the needle plate of the sewing machine;
FIG. 7 is an enlarged detail from FIG. 4;
FIG. 8 is a flow chart of the control process of the sewing machine;
FIG. 9 is a flow chart describing the stitch formation process; and
FIG. 10 is a flow chart of the process where the oscillator drives the stepping motors.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings and in particular to FIG. 1, the sewing machine consists of a, base plate 1, a column 2, a stand 3, a arm 4, and a head 5. A main shaft 6, which is driven by a sewing motor 8 mounted underneath the base plate 1 via a V-belt 7, is mounted in arm 4 in the usual manner. A shuttle shaft 10, which is in a driving connection with a shuttle (not shown), is driven by the main shaft 6 via a toothed belt 9.
The main shaft 6 drives via a crank 11 and a connecting rod 12, a needle bar 14 equipped with the needle 13. The connecting rod 12 is hinged to the needle bar 14 via a hinge connection 15 (FIG. 2). The needle bar 14 is mounted in a rocker arm 17 carried by a rocking shaft 16 (FIG. 1). The rocking shaft 16 is mounted in the arm 4 in parallel to the main shaft 6.
The end of the rocking shaft 16 extending into the stand 3 carries a lever arm 18, which is connected to an eccentric rod 20 via a hinge pin 19. The eccentric rod 20 surrounds an eccentric 21 (FIG. 4), which is rigidly connected to a drive shaft 22 of a stepping motor 23 mounted in the arm 4. The eccentric 21 is guided with a pin 24 in a bore 25 of the arm 4, which bore extends coaxially to the drive shaft 22.
In the lower part of the column 2 (FIG. 2), a support 30 is mounted on an eccentric 31, which has pivot pins 34 and 35 extending into bores 32 and 33 provided in the column 2. The pivot pin 35 is provided with a slot 36. The eccentric 31 is clamped to the support 30 by a screw 37. An upright shaft 38, which is guided in the axial direction by an adjusting ring 39 and a coupling 40, is mounted in the support 30. The lower end of the support 30 is equipped with a flange plate 41, on which a stepping motor 42 is fastened, and the drive shaft 43 of this stepping motor is rigidly connected to the upright shaft 38 via the coupling 40. At its upper end, the upright shaft 38 carries a pinion 44 of a Spiroid gear mechanism 45, whose ring gear 46 is rigidly connected to a pushing wheel 47, which is mounted in a ball bearing in the known manner and has an inner part with an axle stub 48. The axle stub is received in a bore in an arm 30a of the support 30 and can be fixed with a screw 49 after adjustment in the axial direction.
The height of the pushing wheel 47 can be adjusted relative to a needle plate 50, which closes off the column 2 in the upward direction and through which the pushing wheel 47 extends through a slot 50a, by rotating the eccentric 31 by means of the slot 36. In parallel to the slot 50a, the needle plate 50 is provided with a stitch slot 50b for the passage of the needle 13.
The support 30 is firmly clamped to the column 2 by a screw 51, which is screwed into its upper part and extends through a slot 52 in the column 2.
A shaft 53 extending vertically is loosely mounted in the head 5 of the sewing machine. A clamping piece 54 is fastened by screws on the shaft 53. The clamping piece has a radial bore into which a pin 55 is inserted. A coupling piece 56 is loosely mounted on the shaft 53. A web 57, which is located on the side of the coupling piece 56, extends through a slot in the head 5 and secures the clamping piece 56 against rotation. The lower area of the coupling piece 56 is designed as an annular cutout, and thus it surrounds the clamping piece 54. The annular cutout has a recess 59 into which extends the pin 55. The annular cutout is formed at one of its ends with a locking groove 60, while its other end, is formed with a wall 61. A compression spring 62, which is supported by an adjusting ring 63 fastened on the shaft 53, gently presses the coupling piece 56 and consequently the upper wall of its annular cutout in the downward direction against the pin 55.
The free end of a leaf spring 64, which is fastened in the arm 4 and presses the coupling piece 56 in the downward direction, lies on the web 57 (FIG. 3). A lever arm 65 of an angle lever 66 is mounted in the head 5 and is connected via a connecting rod 67 to a lever mechanism (not shown) that can be actuated by the sewing machine operator. The lever arm 65 reaches under the web 57. Under the lever arm 65, a cam 68 is fastened on a shaft 69 mounted in the head 5. The shaft 69 (FIG. 2) carries a hand lever 70 at its end extending to the outside.
A block 71, which is provided with a groove guide 72, is fastened at the lower end of the shaft 53. An angular tab 73, which has an elongated slot and is rigidly connected to a rolling foot support 74, is fastened in the groove guide by screws. The rolling foot support 74 has a pipe connection 75 (cf FIG. 3), which passes over into an end piece 76 extending downward. A bore for fastening an axle stub 78 of a rolling foot 80 is mounted in a ball bearing and is provided in the end piece. The rolling foot 80 has a race 81 to which a ring gear 82 of a Spiroid gear mechanism 83, whose pinion 84 eccentrically meshes with the ring gear 82, is rigidly connected. A tubular support 85, which is locked in its position by screws 86 is screwed into the pipe connection 75, is held in the pipe connection 75. The support 85 consists of a tube 87 joining a hollow cylinder 88 in the upward direction, and an annular connection flange 89. A shaft 90, whose lower end carries the pinion 84, rigidly connected to an annular shoulder 91, and abuts against the lower end of tube 87, is mounted in the tube 87.
In the zone of its upper end, the shaft 90 is surrounded by the inner ring of a ball bearing 93 pressed into the hollow cylinder 88. The upper end of the shaft 90 is rigidly coupled by a coupling 94 with a drive shaft 95 of a stepping motor 96, whose housing is fastened by screws to the closing annular flange 89.
An impulse disk 100, which has two impulse paths, each of which cooperates with a pulse generator 101 and 102, respectively, is fastened to the main shaft 6 (FIG. 1) of the sewing machine. One of the impulse paths has a plurality of impulse markings 103 (FIG. 5) distributed uniformly on the circumference of the disk 100, while the other impulse path has only two impulse markings 104. One of the two impulse markings 104 passes by the pulse generator 101 during the exit of the needle 13 from the part being sewn and the other impulse marking passes by it during the entry of the needle 13 into the part being sewn.
The pulse generator 101 is connected to a control unit 105. A selector 106 is connected to the control unit via a control line 106a. AND gates 107, 108 and 109 are connected to the control unit 105 via the control lines 107a, 108a, and 109a, and counters 111, 112, and 113 are connected to the control unit 105 via a transfer bus 110. In addition, a keyboard 114 is connected to the control unit 105 via a transfer bus 114a, a display unit 115 is connected via a transfer bus 115a, and a data storage unit 116 is connected via a transfer bus 116a. The AND gates 107, 108 and 109 can be switched to "ON", i.e., for transmission of impulses present at their inputs E1. This is done by their inputs E2 being switched by the control unit 105 to High via the control lines 107a, 108a and 109a. The AND gates are switched to "OFF," i.e., no transmission at their inputs E1 when their inputs E2 are switched to Low.
The outputs of the counters 111, 112, and 113 are connected to inputs of power amplifiers 117,118, and 119 for the corresponding stepping motor 23, 42, and 96. In addition, the outputs of the counters 111, 112, and 113 are connected to the control unit 105 via the lines 111a, 112a, and 113a. Lines 117a, 118a, and 119a lead from the control unit 105 to the power amplifiers 117, 118, and 119. Furthermore, three switches 120, 121, and 122 are connected to the control unit 105; among these switches, switch 120 is used to actuate a reverse sewing operation, while the two switches 121 and 122 are provided for the slow drive of the stepping motors 42 and 96 in the forward and reverse directions during stoppage of the sewing machine, preferably with the needle in the raised position. An oscillator 123 is connected for this purpose to the two power amplifiers 118 and 119 via a divider 124 and a switch 125. The switch 125 is connected to the control unit 105 via a control line 125a. The oscillator 123 is also connected to the input F1 of the selector 106. The selector input F2 is connected to the pulse generator 102. The output of the selector 106 is connected to the inputs E1 of the three AND gates 107, 108, and 109, whose outputs are connected to the corresponding counter 111, 112, and 113, which are designed as decremental counters and can be preset individually from the control unit 105 via the transfer bus 110.
The number of steps to be performed by the stepping motors 23, 42, and 96 per sewing stitch and hence the feed length of the individual feeding members--the needle 13, the pushing wheel 47, and the rolling foot 80--between the individual stitches can be preselected with the keyboard 114. It is also possible to select different amounts of feed of the pushing wheel 47 relative to the rolling foot 80. The size of the preselected stitch length is displayed in the display unit 115.
A motor control device 126 is connected to the control unit 105 via a transfer bus 126a. The motor control device 126 is intended especially for controlling the sewing motor 8 and is connected thereto via a line 8a. A speed set value generator 127, designed as a pedal-operated member, is connected to the motor control device 126 via a transfer bus 127a. A counter 128 is connected to the control unit 105 via a transfer bus 128a and a line 128b, and to the pulse generator 101 via a line 128c.
The device operates as follows:
The sewing machine operator selects the desired amounts of feed of the needle 13, the pushing wheel 47, and the rolling foot 80 via the keyboard 114. Corresponding digital values are then retrieved from the data storage unit 116 via the control unit 105, and the counters 111, 112, and 113 are thus preset. Values corresponding to the amounts of feed are displayed in the display unit 115 at the same time.
During the operation of the sewing machine, the sewing motor 8 drives the main shaft 6 via the V-belt 7. The main shaft moves the needle bar 14 up and down via the drive connection formed by the crank 11 and the connecting rod 12. The main shaft 6 also drives the shuttle (not shown) via the toothed belt 9 and the shuttle drive shaft 10. The drive for feeding the part to be sewn is always generated, via the pulse generator 101, when the needle 13 is penetrating into the part to be sewn and when it again leaves the part to be sewn. The pulse generator 101 sends an impulse to the control unit 105 on passage of the impulse marking 104 through the pulse generator 101. The control unit now switches the potential on the inputs E2 of the AND gates 107, 108, and 109 to High via the control lines 107a, 108a, and 109a. The impulses subsequently sent by the pulse generator 102 on passage of the impulse markings 103, will now be transmitted by the AND gates 107, 108, and 109 to the counters 111, 112, and 113 via the selector 106 which is switched by the control unit 105 via the line 106a to input E2 during the drive of the sewing machine.
When one of the counters 111, 112 or 113 has reached the count "0", it sends a control impulse to the corresponding power amplifier 117, 118 or 119, as a result of which the corresponding stepping motor 23, 42 or 96 is tripped by one step of rotation. At the same time, this counter 111, 112 or 113 sends an impulse via a corresponding control line 111a, 112a and 113a to the control unit 105, which again presets this counter 111, 112 or 113 to a new value. The control unit 116 now polls the corresponding values from the data storage unit 116. At the same time, via the control lines 117a, 118a, and 119a connected to the power amplifiers 117, 118, and 119, the control unit determines whether the corresponding stepping motor 23, 42, and 96 is moved in the forward or reverse direction of rotation. On the passage of the second impulse marking 104 through the pulse generator 101, the process described is repeated. The stepping motors 23, 42 and 96 thus perform their predetermined number of steps and consequently the above-mentioned half amount of feed within half of one revolution of the pulse disk 100. The values that can be preset on the counters 111, 112, and 113 are selected so that the stepping motors 23, 42, and 96 can perform their maximum number of steps both during the phase in which the needle 13 has been removed from the fabric being sewn and during the phase in which the needle 13 has entered the fabric.
The tripping impulses acting on the stepping motors 23, 42, and 96 drive the rocker arm 17, the pushing wheel 47, and the rolling foot 80 to exert a joint feeding effect on the part being sewn. The stepping motor 42 now rotates the pushing wheel 47 via the upright shaft 38 that is rigidly coupled with its drive shaft 43 and via the Spiroid gear mechanism 45. At the same time the stepping motor 96 drives the rolling foot 80 via the shaft 90 that is rigidly coupled with its drive shaft 95 and the Spiroid gear mechanism 83. Also at the same time, the stepping motor 23 rotates the eccentric 21 stepwise in one direction via its drive shaft 22. The eccentric 21 transmits deflecting movements to the rocker arm 17 via the eccentric rod 20 and the lever arm 18. As a result of which the rocker arm 17 will swivel through corresponding angles. With the needle 13 in the fabric, this swivel takes place synchronously with the feed of the pushing wheel 47 and the rolling foot 80. When the needle 13 has been withdrawn from the fabric, this swivel is brought about by driving the eccentric 21 in the opposite direction.
The needle bar 14 is known to perform a sinusoidal oscillating movement in the direction of feed. It oscillates in the direction of feed during its phase in which it is within the fabric and in the opposite direction during the phase in which it is withdrawn from the fabric. The control device of the stepping motor 23 for swiveling the needle bar 14 is therefore designed so that during one revolution of the main shaft 6, i.e., during each feed between two stitch formations, it generates two sinusoidal component step sequences. One step sequence drives the stepping motor 23 in the direction of feed and the other drives the motor in the opposite direction. The stepping motors 42 and 96 for the pushing wheel 47 and the rolling foot 80 are advantageously also driven in two sinusoidal component step sequences rather than in a constant step sequence.
After the individual stepping motors 23, 42, and 96 have performed the numbers of steps in accordance with the data set on the keyboard 114 and polled correspondingly from the data storage unit 116, the input E2 of the corresponding AND element 107, 108 or 109 is switched by the control unit 105 via the control line 107a, 108a or 109a to potential L. Thus the further transmission of the tripping impulses from the pulse generator 102 is prevented by the corresponding AND element 107, 108 or 109.
To secure the stitch formation, the control unit 105 displaces the axis of the needle 13 into the end zone of the stitch slot 50b in the needle plate 50 prior to each sewing operation. To do so, the control unit 105 tests the state of the sewing motor 8 and the speed set value generator 127 via the transfer bus 126a. When the sewing motor 8 is stopped, the control unit 105 sends a signal via the transfer bus 126a to the motor control device 126, which will at first prevent the sewing motor 8 from being started.
During normal stitch formation, the amplitude of oscillation of the needle 13 around the center line M of the stitch slot 50b equals S/2 in which S is one full stitch length. From the stitch length S entered via the keyboard 114, the length L of the stitch slot 50b in the needle plate 50, and a selectable value K which corresponds to a residual or minimal distance between the needle 13 and the end of the stitch hole 50b, the control unit 105 calculates a displacement value W, at which the first entry of the needle 13 into the fabric is to take place during the next sewing operation. The displacement W of the needle 13 into the end zone of the stitch slot 50b from the center line M consequently equals L/2 minus half the amplitude of the oscillation S/2 minus the residual or safety distance K which the needle must keep from the end of the stitch slot. Thus, W=L/2-S/4-K.
For the first entry of the needle 13 cooperating with the pushing wheel 47 and the rolling foot 80, the control unit 105 reads from the data storage unit 116 corresponding digital values which correspond to the calculated value W, and thus brings about presetting of the counters 111, 112, and 113 via the transfer bus 110. The control unit 105 subsequently switches the selector 106 to F1, so that the impulses or High or Low values sent by the oscillator 123 can be transmitted to the inputs E1 of the AND gates 107, 108, and 109 in order to prompt a sewing operation with the sewing motor 8 stopped.
As soon as the control unit 105 receives the information via the control device 126 that the speed set value generator 127 is actuated, it switches the potential on the inputs E2 of the AND gates 107, 108, and 109 to High via control lines 107a, 108a, and 109a. The impulses sent by the oscillator 123 will now be transmitted to the counters 111, 112, and 113 via the selector 106 located in front of the AND gates 107, 108, and 109. The selector is switched to the input F1 when the sewing motor 8 is stopped.
The stepping motors 23, 42, and 96 will move in the above-described manner until the number of steps preset in the data storage unit 116 for driving the pushing wheel, the rolling foot, and the needle has been carried out. The inputs E2 of the corresponding AND gates 107, 108 or 109 are now switched by the control unit 105 to potential Low via the control line 107a, 108a or 109a, so that the further transmission of the timing impulses from the pulse generator 102 is prevented by the corresponding AND element 107, 108 or 109. At the same time, the sewing motor 8 is restarted via the collecting line 126a. The axis of the needle 13 has been swiveled by the value W and S/4 to the position S1 (FIG. 7) from the middle position M.
Via the transfer bus 128a, the counter 128 is loaded with a preselectable digital signal, which corresponds to the number of initial stitches that are to be made during the starting phase of sewing, after which the needle bar 14 is to return into its normal sewing position in the middle of the stitch slot 50b.
The selector 106 is switched by the control unit 105 to F2, so that the impulses sent by the impulse generator 102 will be transmitted to the inputs E1 of the AND gates 107, 108, and 109. However, data is input into the counters 111, 112, and 113 for performing the first stitch.
The motor control device 126 now drives the sewing motor 8 at the speed preselected by the speed set value generator 127. The first stitch is formed without feed, because the counters 111, 112, and 113 contain no data that would cause the stepping motors 23, 42, and 96 to be driven.
After the first stitch, the further stitches are made with the stitch length S entered via the keyboard 114 in the above-described manner by polling corresponding data from the data storage unit 116, and the needle performs its feed motion in the range designated by S'/2 in FIG. 7, so that satisfactory stitch formation takes place even during the first stitch. The counter 128 counts down by "1" on each stitch. As soon as the counter 128 reaches "0", the formation of the initial stitches is terminated. The counter 128 sends an impulse to the control unit 105 via the line 128b, after which, during the withdrawal of the needle 13 from the fabric being sewn, the next impulse of the pulse generator 101 induces a movement which causes the axis of the needle 13, the pushing wheel 47, and the rolling foot 80 to be moved back before the next stitch by the same amount by which they were moved forward in the direction of feed prior to the sewing operation. Thus, the needle 13 will again swing out during the further stitch formation in the middle zone of the stitch hole 50b of the needle plate 50 designated by S/2 in FIG. 7.
FIG. 8 shows a flow chart of the control process of the sewing machine, as is controlled by the control unit 105 of the circuit shown in FIG. 5.
After the sewing machine is started by switching on a main switch (not shown), polling is performed to determine whether the stitch length was changed 201. If it was changed, the control unit 105 calculates a new displacement value W 202; otherwise, the previous displacement value W is retained. For safety's sake, the sewing motor 8 is then switched off 203. Oscillator drive subroutine 204 (FIG. 10) of the stepping motors 23, 42, and 96 is now performed to displace the rocker arm 17 of the needle 13 to the end of the stitch slot 50b by the displacement value W from the middle M (FIG. 7).
During this oscillator drive, the selector switch 106 is switched to F1 239, and the AND gates 107, 108, and 109 are switched to "ON" 240. The counters 111, 112, and 113 are loaded with data values to generate the displacement of the rocker arm 17 by the displacement value W 241. A polling is performed to determine whether the displacement is a reverse displacement 242. If it is not, a polling is performed to determine whether an impulse from the oscillator 123 is present 244. Each counter 111, 245, 112, 244, and 113, 251 will then count down by "1" under the effect of the successive impulses from the oscillator 123. In the next step, the counters 111, 246, 112, 249, and 113, 252 are checked to determine whether their values equal "0". If not, the next impulse of the oscillator 123 is awaited in step 244. If one of the counters 111, 112, 113 is at "0", the corresponding stepping motor 23, 42, or 96 is tripped by one step in the steps 247, 250 or 253.
A polling is now performed 254 to determine whether the displacement of the rocker arm 17 has been completed. If not, the counters 111, 112, and 113 are set to new data values in step 255, and the count down process is repeated until the displacement is complete. Another polling is now performed 256 to determine whether a reverse displacement is present. If the displacement is not a reverse displacement, the selector switch 106 is switched to F2 and the AND gates 107, 108, and 109 are switched to "OFF" 259. The subroutine will thus return to step 205 in FIG. 8.
Counter 128 is set to the number of initial stitches here 205, and the sewing motor 8 is connected 206.
A polling is now performed 207 to determine whether this is the first stitch formation after the beginning of the sewing process. If yes, the counters 111, 112, and 113 are set to "0" 208. Regardless of whether the result of the polling was "YES" or "NO", a stitch is now performed 209, as will be described below on the basis of FIG. 9. If this is the first stitch formation, no feed of the fabric to be sewn is brought about by the stepping motors 23, 42, and 96, because the counters 111, 112, and 113 were set to "0".
After the stitch has been prepared, the counter 128 counts down by "1" 210, and a polling is performed to determine whether it is at "0" 211. The stitch formation is now continued until the counter 128 reaches "0", after which the sewing motor 8 is again turned off 212. The initial stitches to be prepared in the end zone of the stitch slot 50b have thus been prepared.
An oscillator drive 213 of the stepping motors 23, 42, and 90 is now again performed to displace the rocker arm 17 of the needle 13 back to the middle M of the stitch slot 50b by the displacement value W. The process takes place according to the flow chart shown in FIG. 10, but this time it is determined in step 242 that the displacement is a reverse displacement and switching over of the power amplifiers 117, 118, and 119 is now performed in step 243 via the lines 117a, 118a, and 119a in order to reverse the displacement of the rocker arm 17. The switching over of the power amplifiers 117, 118, and 119 is also abolished in step 257.
After completion of the displacement of the rocker arm 17, the sewing motor 8 is again turned on 214, and normal sewing stitches according to the subroutine 215 corresponding to FIG. 9 are now prepared.
After each completed stitch formation, a polling is performed 216 to determine whether the speed set value generator 127 is still being actuated. As long as it is actuated, one more stitch is prepared. It the set value generator 127 is not actuated, a polling is performed 217 to determine whether the presser foot was raised and consequently sewing was terminated. If yes, the sewing motor 8 is turned off 218, and the oscillator drive subroutine 219 according to FIG. 10 is performed, and the stepping motors 23, 42, and 96 are consequently driven via the oscillator 123 in the above-described manner as long as the needle 13 stands in its upper position 220, after which the AND gates 107, 108, and 109 are switched to "OFF" 221.
The stitch formation according to FIG. 9 is performed by first switching the selector switch 106 to F2 222. A polling is then performed to determine whether an impulse from the pulse generator 101 223 is present. As soon as such an impulse is present, the AND gates 107, 108, and 109 are switched to High 224. The data values for the stitch length are loaded into the counters 112, and 113, 225. In the presence of an impulse from the pulse generator 102, 226, the counters 111, 227, 112, 230, and 113, 233 count down by "1". This happens until they reach "0" 228, 229, 234, after which the stepping motors 23, 42, and 96 each perform one step 229, 232, and 235.
A testing is then performed to determine whether the intended stitch feed has been completed by all three stepping motors 23, 42, and 96 236. If not, the next data values are loaded into the counters 111, 112, and 113 237, after which--at the next impulse of the pulse generator 102--the described countdown process of the counters 111, 112, and 113 is performed, and the yet-to-be-performed steps of the stepping motors 23, 42, and 96 are performed long as the stitch feed set is being performed. The AND gates 107, 108, and 109 are then switched to "OFF" 238, and stitch formation of an individual stitch is terminated.
The switch 120 in FIG. 5 is used for short-term reverse sewing during stitch formation, i.e., when the selector 106 is switched to F2 and the AND gates 107, 108, and 109 are switched to "ON". Switch 120 will now only switch over the power amplifiers 117, 118, and 119 via the lines 117a, 118a, and 119a in order to reverse the drive of the stepping motors 23, 42, and 96, respectively, and consequently the feed as well.
The two switches 121 and 122 are used to slowly drive the stepping motors 42 and 96 in the forward and reverse direction during stoppage of the machine, when the needle 13 is in the high position. On actuating one of the two switches 121 or 122, the switch 125 is closed by the control unit 105, so that via the divider 124, which passes through only a reduced part of the impulses of the oscillator 123, these reduced impulses are sent via the oscillator 123 to the two power amplifiers 118 and 119. On actuating switch 122, the two power amplifiers 118 and 119 are also switched over at the same time via the lines 118a and 119a in order to reverse the direction of the feed to be performed.
The captions for the individual boxes are here now listed.
201=Has stitch length been changed?
202=Calculate new W value
203=Sewing motor 8 off
204=Oscillator drive subroutine
205=Set counter 128 to the number of initial stitches
206=Sewing motor 8 on
207=First stitch formation?
208=Set counters 111, 112, and 113 to "0"
209=Stitch formation subroutine
210=Counter 128: n=n-1
211=Has counter 128 been set to "0"?
212=Sewing motor 8 off
213=Oscillator drive subroutine
214=Sewing motor 8 on
215=Stitch formation subroutine
216=Has speed set value generator 127 been actuated?
217=Is presser foot in top position?
218=Sewing motor 8 off
219=Oscillator drive subroutine
220=Is needle in top position?
221=AND gates 107, 108, and 109 "OFF"
222=Selector 106 to F2
223=Impulse from pulse generator 101?
224=AND gates 107, 108, 109 to High
225=Load data values into counters 111, 112, and 113
226=Impulse from pulse generator 102?
227=Counter 111: n=n-1
228=Counter 111: n=0?
229=Stepping motor 23 performs one step
230=Counter 112: n=n-1
231=Counter 112: n=0?
232=Stepping motor 42 performs one step
233=Counter 113: n=n-1
234=Counter 113: n=0?
235=Stepping motor 96 performs one step
236=Has stitch feed been completed?
237=Load new data value into counters 111, 112, and 113
238=AND gates 107, 108, and 109 to High
239=Selector 106 to F1
240=AND gates 107, 108, and 109 to Low
241=Load data values into counters 111, 112, and 113
242=Reverse displacement?
243=Switching over of the power amplifiers 117, 118, 119
244=Impulse from oscillator 123
245=Counter 111 : n=n-1
246=Counter 111: n=0?
247=Stepping motor 23 performs one step
248=Counter 112: n=n-1
249=Counter 112: n=07
250=Stepping motor 42 performs one step
251=Counter 113: n=n-1
252=Counter 113: n=0?
253=Stepping motor 96 performs one step
254=Has displacement of the rocker arm 17 been concluded?
255=Load new data values into counters 111, 112, and 113
256=Reverse displacement?
257=Switching over of the power amplifiers 117, 118, 119
258=Selector 106 to F2
259=AND gates 107, 108, and 109 to Low
If the sewing operation is begun with a stitch sequence extending in the reverse direction, when, e.g., the button 120 for reverse sewing is actuated at the beginning of sewing the control device 105 shifts the axis of the needle 13 into the front area of the stitch hole 50b of the needle plate 50, i.e., into the area directed toward the sewing machine operation. The initial stitches are then made in a reversed feed direction analogously to the above-described embodiment in normal feed setting, after which the axis of the needle 13 is displaced into its middle area.
According to another embodiment of the present invention, it is also possible to stop the needle 13 during the preparation of the initial stitches by setting the counter 111 to "0" during this time. During the preparation of these initial stitches the material to be sewn is fed exclusively by the pushing wheel 47 and the rolling foot 80.
When the needle 13 leaves the material being sewn in the end zone of the stitch hole 50b after performing the first sewing stitch, the impulse now generated by the pulse generator 101 causes, via the control unit 105, the needle bar guide 17 to stop. At the same time, during the phase in which the needle 13 has been withdrawn from the fabric, the control unit 105 controls the entire feed motion of the pushing wheel 47 and the rolling foot 80 to prepare a stitch with the stitch length S set, while it prevents the pushing wheel 47 and the rolling foot 80 from being fed during the phase in which the needle 13 has penetrated into the fabric.
This stitching operation is performed until the counter 128 (FIG. 5), on which the number of initial stitches has been preselected, has been reset and it sends an impulse to the control unit 105 via the line 128b.
As was described in connection with the preceding embodiment, this impulse induces the reverse movement of the needle 13, and the needle is moved to above its next point of penetration into the fabric to be sewn. The further stitch formation is then again performed in the middle areas of the stitch hole 50b of the needle plate 50.
For reverse sewing, e.g., for bar tacking at the end of the seam, the switch 120 is actuated. As a result of this the control unit 105 reverses the direction of rotation of the stepping motors 23, 42, and 96 at the beginning of a new impulse sent by the impulse generator 101, via the control lines 117a, 118a, and 119a to the power amplifiers 117, 118, and 119, so that the stepping motors will drive the pushing wheel 47, the rolling foot 80, and the needle bar 14 in the opposite direction as long as the switch 120 is being actuated. The stepping motors 23, 42, and 96 now perform the sequence of steps in the above-described manner by polling the corresponding values set via the keyboard 114 from the data storage unit 118.
During the stopping of the sewing machine, which usually ends at the top dead center of the needle 13, the control unit 105 switches the selector 106 to an input F1, so that the impulses generated by the oscillator 123 are sent to the inputs E1 of the AND gates 107, 108, and 109. As soon as the sewing machine stops, timing impulses are sent from the oscillator 123 to the inputs E1 of the AND gates 107, 108, and 109 instead of the timing impulses from the pulse generator 102. Thus, the preselected feed of the needle 13, the pushing wheel 47, and the rolling foot 80 is completed even after the last withdrawal of the needle 13 from the fabric being sewn, so that the needle 13 is already located above the location of the next needle penetration. As soon as the end position of the preselected amount of feed has been reached, the control unit 105 switches off the AND gates 107, 108, and 109 via the control lines 107a, 108a, and 109a. | The invention describes a process for carrying out a sewing operation with a sewing machine having a needle feed.
In present sewing operations with a sewing machine having needle feed, defective stitches are often formed at the beginning, because the initial threads are not sufficiently clamped in the needle plate as a consequence of the elongated stitch hole. In the new process, the position of the needle prior to the beginning of sewing is displaced into an end zone of the stitch hole for performing a preselected number of initial stitches. | 3 |
This is a division of application Ser. No. 663,334, filed Oct. 22, 1984, now U.S. Pat. No. 4,613,310, Sept. 23, 1986 which is a continuation of application Ser. No. 405,916, filed Aug. 6, 1982, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to an outboard motor and more particularly to an improved cowling construction for the power head of such a motor.
Frequently, outboard motors are employed as auxiliary power units for sailboats. In many such installations, particularly with larger sailing craft, the outboard motor is carried by the stern of the sailing vessel at a level considerably lower than the rear deck. As a result, in order to pull the recoil starter associated with conventional outboard motors, the operator must pull the starting rope at an angle to that for which it is normally designed. That is, most outboard motors employ a recoil starter in which the starting rope is pulled in a substantially horizontal direction. However, when the outboard motor is used as an auxiliary power unit for a sailing vessel, the starting rope must be pulled at an upwardly inclined angle due to the lower positioning of the motor relative to the rear deck on which the operator is positioned. As a result, it is more difficult to pull the starting rope and starting difficulties can well be encountered.
It is, therefore, a principal object of this invention to provide an improved starting arrangement for outboard motors rendering them more adaptable to use as auxiliary power units on sailboats.
It is a further object of the invention to provide an improved cowling unit for an outboard motor that facilitates starting when associated as a power unit for a sailing vessel.
It is yet a further object of this invention to provide an improved cowling unit for an outboard motor that facilitates starting when used as an auxiliary power unit, which offers an instrument panel and which also facilitates servicing of the motor.
One of the prime difficulties in the design of outboard motors is silencing. Since the power unit is positioned above the water level and in close proximity to the operator, noise can well be a problem. It has been conventional practice to enclose the power head within an outer cowling so as to, among other things, minimize the transmission of noise. The outer cowling associated with most outboard motors includes an upper cover and lower tray. Heretofore, it has been the practice to form at least the lower tray from metal so as to insure good sealing between the upper housing and the tray. Although the use of plastic such as synthetic resins can significantly improve silencing, such materials have not heretofore been used for the lower tray because of the difficulties of insuring good sealing, particularly when the material properties change with age.
It is, therefore, a further object of this invention to provide an improved outer cowling for an outboard motor.
It is another object of this invention to provide an outer cowling for an outboard motor that may be formed from synthetic resin and which will insure good sealing throughout the life of the unit.
SUMMARY OF THE INVENTION
A first feature of the invention is adapted to be embodied in an outboard motor construction having a power head with an outer cowling. In accordance with this feature of the invention, the outer cowling has an inclined portion extending upwardly and rearwardly to form a face that may be seen from above. A starter handle is accessible from the inclined portion of the outer cowling.
Another feature of the invention is adapted to be embodied in an outer cowling arrangement for the power head for an outboard motor or the like. Such an outer cowling and arrangement includes a lower tray portion formed from a synthetic resin and an upper housing portion also formed from a synthetic resin. A supporting member is affixed to one of the portions and in turn carries a retaining member. Releasable latch means are carried by the other of the portions and is engageable with the retaining member for holding the cowling portions together.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a sailboat with an attached auxiliary power unit in the form of an outboard motor constructed in accordance with this invention.
FIG. 2 is an enlarged view of the area encompassed by the circle 2 in FIG. 1.
FIG. 3 is a further enlarged cross-sectional view showing the outer cowling arrangement associated with the outboard motor.
FIG. 4 is a yet further enlarged cross-sectional view of the forward portion of the outer cowling unit.
FIG. 5 is a cross-sectional view taken along the line 5--5 of FIG. 4.
FIG. 6 is a front elevational view of the outer cowling unit, with a portion broken away, to more clearly show the construction.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIGS. 1 and 2, a sailing vessel such as a cruiser, is identified generally by the reference numeral 11. The sailing cruiser 11 has a stern 12 to which an outrigger 13 is affixed so as to detachably support an outboard motor constructed in accordance with this invention, indicated generally by the reference numeral 14.
The motor 14 includes a clamping assembly 15 for detachably affixing the motor 14 to the outrigger 13 or to the stern of a boat in a known manner. The motor 14 includes a power head assembly, indicated generally by the reference numeral 16, a driveshaft housing 17 and a lower unit 18 including a driven propeller 19.
Referring now to the remaining figures, the power head 16 includes an internal combustion engine, shown in phantom and indicated generally by the reference numeral 21. The engine 21 is contained within an outer protective cowling constructed in accordance with the invention and including a lower tray portion 22 and an upper cover portion 23. In accordance with the invention, the tray portion 22 and upper cover portion 23 are formed from a suitable plastic material such as a synthetic resin so as to improve the sound deadening and reduce the transmissions of sounds from the engine 21 to the occupants of the associated watercarft such as the sailboat 11.
Normally, it has been considered to be impractical to form both the lower tray portion and upper cover portion of the cowling from a synthetic resin. The reason for this has been the difficulty of obtaining effective sealing between two such resinous pieces, particularly when the resin ages and is subject to deformation. In accordance with this invention, an arrangement is provided wherein the tray portion 22 and cover portion 23 are affixed together by a intermediate member so as to improve the sealing throughout the life of the unit.
In accordance with the invention, a supporting member 24, formed from a more rigid material such as a metal, is affixed to the forwardmost portion of the tray portion 22 by means of threaded fasteners 25. The supporting member 24 has in turn affixed to it a retaining member, indicated generally by the reference numeral 26. The retaining member 26 is affixed to the supporting member 24 by means of threaded fasteners 27 and is also formed from a more rigid material such as metal. The retaining member 26 extends generally upwardly into the forwardmost portion of the top cover portion 22 and has a forwardly extending portion 28 that cooperates to form a latch assembly, in a manner to be described. The top cover portion 23 has an inclined forward face 29 for a reason to be described. The forward face 29 and side and rear portions of the cover 22 terminate in depending flange portions 31 to which a seal 32 is affixed. The seal 32 engages and seals a corresponding upper portion of the lower tray 22.
To affix the cover 23 to the tray 22, a resilient latch member 33 is affixed to the forwardmost depending flange 31 and is adapted to extend into a recess 34 formed in the retaining member 26 so as to underlie the portion 28 and afford a detachable connection between the forwardmost portion of the cover 23 and the tray 22 via the retaining member 26.
A retaining member 35 (FIG. 3) is affixed to the flange 32 of the rear portion of the top cover 23. A pivotable supported latch 36 is engaged with the retaining member 35. A threaded fastener 37 fixes the latch 36 to a shaft 38 journalled in the lower tray 22. A handle 40 is fixed to the outer end of the shaft 38 for operation of the latch between latched and unlatched positions so the retainer 35 and latch 36 form a releasable latching assembly 39.
The lower tray 22 is formed with a central opening in which a gasket 41 is formed so as to provide sealing engagement with a flange 42 formed at the upper end of the driveshaft housing 17.
The outboard motor 14 is provided with a steering tiller 43 (FIGS. 1 and 2) that extends forwardly of the motor. In addition, a rotatable throttle handle 44 is positioned at the forward end of the tiller 43 for throttle control of the engine 21 in a known manner.
A shift mechanism is also employed that includes a control lever 45 (FIG. 3) that is operated in a known manner. The shift lever 45 is movable between a neutral position, as shown in FIG. 3, and a forward or reverse position. A detent mechanism 46 including a leaf spring 47 that is affixed to the supporting member 24 by means of a threaded fastener 48 is provided for retaining the shift lever 45 in each of its three positions. The lever 45 is connected to the transmission mechanism in the lower unit 28 (not shown) by means of a shift control rod 49.
As has been noted, the cover portion 23 has a face 29 that is inclined upwardly and rearwardly when the motor 14 is attached to the boat 11. The reason for this may be best understood by reference to FIGS. 1 and 2 as well as the remaining figures. The engine 21 is provided with a conventional recoil starter mechanism, indicated generally by the reference numeral 51, that is operated by means of a starter rope 52. With a conventional outboard motor arrangement, the starter rope 52 extends generally horizontally through the front face of the outer cowling and terminates at its starter handle 53. Such a horizontal arrangement is not suitable when the motor 14 is used to power a boat such as a sailboat 11. As may be readily seen from FIGS. 1 and 2, an operator standing on the deck of the boat adjacent the transom 12 must reach downwardly to have access to the starting handle 53. Thus, if the starting handle 53 and rope 52 are normally operated in a horizontal manner, it will be necessary for the operator to pull the handle 53 upwardy to clear the top of the transom 12. With conventional arrangements, this is awkward and furthermore reduces the effectiveness of the operator on operating the starter 51 to give rise to starter difficulties. In accordance with this invention, however, the starting rope may be pulled upwardly in the direction of the arrow 54 in FIG. 2 so as to effect starting due to an internal guide in the mechanism which will cause the normal starting direction of the rope 52 to follow the path of the arrow 54. This mechanism will now be described.
The sloping front side 29 of the top cover 23 is formed with an opening, indicated generally by the reference numeral 55. The opening 55 is normally closed by a control or operational panel 56. The panel 56 is formed with an integral hinged portion 57 that is pivotally connected to the retainer 26 by means of a pivot pin 58. The pivot pin 58 is held in position by means of a retaining pin 59. A seal 61 carried by the operational plate 56 and a seal 62 carried by the cover 23 around the opening 55 provide a water tight seal when the operational plate 56 is in its normal closed position. The plate 56 is maintained in this position by means of one or more threaded fasteners 63 cast into the plate 59 and nuts 64 that underlie the retainer 26.
The forward portion of the cover plate or operational board 56 is provided with a central opening 65 through which the starter rope 52 extends. Adjacent to the location of this opening when the board 56 is in its closed position, a guide 66 formed integrally with the retainer 26 engages the rope 52 and redirects its motion so that it will move along the line defined by the arrow 54 when the engine is started. Thus, no mechanical advantage will be lost and operation of the starter 51 from a higher level will be facilitated.
The panel 56 may, in addition to affording ease of operation of the starting handle 53, carry a number of instruments for indicating the condition of the engine 21. Because of the inclined angle of the panel 56 and the top cowling portion 29, these instruments may be readily viewed from an operator on the deck of the boat along the sight line 67 (FIG. 2). Such instruments are shown in FIG. 6 and may comprise an oil indicator 68, a stop switch 69, a tachometer 71 and a temperature gauge 72. Of course, other instruments may readily be used in conjunction with the panel 56.
It should be noted that the fact that the operational panel 56 is pivotally connected, not to the cover portion 23 but to the tray portion 22, permits ready detachment of the cover portion 23 for servicing of the engine. Furthermore, this simplifies the overall construction of the top cover portion 23. In addition, the operational panel 56 may be readily pivoted forwarded to the broken line position shown in FIG. 4 to afford access to the engine 21 and servicing by removal of the nuts 64. Thus, even though the panel 56 is inclined, it may be readily moved to a non-interferring forward position wherein servicing is facilitated.
Although there are advantages in having the operational panel 56 pivotal, it is to be understood that the invention may be employed in conjunction with arrangements wherein the panel 56 is rigidly carried by the retaining member 26. Also, although the invention is described in conjunction with the use of the motor 14 with a sailboat 11, it is to be understood that certain facets of the invention may be employed in conjunction with other types of watercraft. For example, the silencing afforded by having the tray 22 and cover portion 23 formed from synthetic resin with the attendant sealing improvement can be enjoyed with any outboard motor application. In addition, the inclination of the angle of operation of the starting handle 53 from the horizontal may be enjoyed in certain other arrangements as can the inclination of the panel on which the instruments are provided. Various other changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims. | An improved outer cowling arrangement for the power head of an outboard motor in which both the tray and top housing are formed from a synthetic resin for improving silencing. To insure a good fit and sealing, a supporting member and retaining member are affixed to each other and the supporting member is carried by one of the portions. Releasable latching means are carried by the other portion to engage the retainer member for holding the cowling portions together. The top housing has an inclined forward face in which a panel is positioned for passing the starting handle and starting rope. A guide defines a path of movement for the starting rope that is perpendicular to this inclined surface so that the motor can easily be started from a higher level, for example, when used as an auxiliary power source for a sailboat. | 1 |
This is a divisional of U.S. application Ser. No. 08/245,718 filed May 18, 1994, now abandoned, which is a divisional of U.S. application Ser. No. 08/102,658 filed Aug. 5, 1993, now U.S. Pat. No. 5,342,959 issued Aug. 30, 1994, which is a continuation of U.S. application Ser. No. 07/923,209 filed Jul. 31, 1992, now abandoned.
FIELD OF INVENTION
This invention relates to a novel method for preparing the enantiomeric forms of certain known racemic imidazole-1-ethanol derivatives which are useful as radiosensitizing or chemosensitizing agents. Novel intermediates utilized in this process are also involved as well as the chiral final products.
BACKGROUND OF INVENTION
The racemic mixture of certain compounds of the present invention is described in U.S. Patent 4,954,515 and 5,098,921. In particular, Example 2 of both patents describes the racemic mixture of the compound of Formula I set forth below wherein X is bromo. The racemic mixture of certain compounds of the present invention is also described generically as starting materials or intermediates in the following U.S. Pat. Nos. 4,596,817; 4,631,289; 4,757,148. Additionally, the racemic mixture of certain compounds of Formula I is described generically in U.S. Pat. No. 4,241,060 as hypoxic-cell radiosensitizers.
SUMMARY OF INVENTION
The present invention provides a novel process for the preparation of the enantiomers of compounds of the following general formula: ##STR3## wherein X is halogen or ##STR4##
In Formula I, X can be chlorine, bromine, fluorine, or iodine and preferably X is bromine or chlorine, and more preferably X is bromine, and R 1 can be OH, methyl, phenyl, or phenyl substituted as defined herein for R.
The present invention also provides novel intermediates useful in the preparation of the enantiomers of the compounds of Formula I. These novel intermediates have the following structures: ##STR5##
The compound depicted as Formula II above is 3-[3-(2-nitro-1H-imidazol-1-yl)-2-[(tri-R-silyl)oxy]propyl]-2-oxazolidinone. Formula III is 3-[2-hydroxy-3-(2-nitro-1H-imidazol-1-yl)propyl]-2-oxazolidinone; and Formula IV is (1-aziridinylmethyl)-2-nitro-1H-imidazole-1-ethanol. Preferably, R in Compound II is methyl.
The compounds of Formula I and each of the compounds of Formulas II, III, and IV exist in the (R)-(+) or (S)-(-) enantiomeric form or in the (R)-(-) or (S)-(+) enantiomeric form. The most preferred compound of the present invention is the (R)-(+) enantiomer of Formula I wherein X is bromo and this compound is depicted as follows: ##STR6## Pharmaceutically acceptable salts of the compound of Formula I are also within the present invention. These include salts of inorganic and organic acids, preferably inorganic acids such as hydrochloric, hydrobromic, and hydriodic acid. Most preferred of the salts is the hydrobromide.
The preferred enantiomer for the compound of Formula II where R is methyl is the (S)-(+) enantiomer; for the compound of Formula III is the (S)-(-) enantiomer, and for the compound of Formula IV is the (R)-(-) enantiomer.
The novel process of the present invention comprises reacting chiral 2-nitro-1-(2-oxiranylmethyl)-1H-imidazole with a 2-oxazolidinone of the formula ##STR7## wherein R is a lower alkyl group having from 1 to 4 carbon atoms, phenyl or phenyl substituted with lower alkyl having from 1 to 4 carbon atoms, lower alkoxy having from 1 to 4 carbon atoms, hydroxy, halogen such as chlorine, bromine, or fluorine, nitro, amino, or trifluoromethyl in the presence of a suitable catalyst to give a chiral compound of the formula ##STR8## wherein R has the meaning defined above which is (a) hydrolyzed, for example, with potassium fluoride in methanol or acetic acid in methanol to give chiral 3-[2-hydroxy-3-(2-nitro-1H-imidazol-1-yl)propyl]-2-oxazolidinone which is treated with an appropriate acid of formula HX wherein X is as defined above, preferably in acetic acid; the preferred acid being hydrobromic acid; or (b) treated in one step with such an acid to give a compound of Formula I.
DETAILED DESCRIPTION OF INVENTION
The compounds of Formula I are prepared as depicted in Chart I hereof. Although the preferred reagents and solvents are depicted in each of the steps, it is readily apparent that the reaction conditions may be varied somewhat. For example, in Step 1, suitable solvents include epichlorohydrin alone, lower aliphatic alcohols, water, ethers such as diethyl ether, and diisopropyl ether or tetrahydrofuran, and lower dialkyl ketones such as acetone. Typical bases that can be used include essentially all metal carbonates, especially those of Group I metals (Na, K, Rb, Cs), also common amine bases such as the tertiary lower alkyl amines (triethylamine, diisopropyl ethylamine, N--Me--pyrrolidine, etc). Also common metal hydrides such as NaH. Quaternary ammonium bases such as nBu 4 N + OH - , nBu 4 N + Cl - , etc; various fluoride bases such as nBu 4 NF, KF, CsF, etc. The temperature of the reaction in Step 1 can vary from room temperature to about 150° C.
In Step 2 of Chart I typical solvents which can be employed include various ethers, lower alcohols; other chlorinated solvents, aromatic hydrocarbons such as benzene, toluene; dipolar aprotic solvents such as DMF, lower dialkyl ketones, lower alkyl nitriles. In Step 2 the temperature can vary from -50° C. to 50° C. and the bases used can be the same as in Step 1.
In Step 3 of Chart I, in addition to using 3-tri-R-silyl-2-oxazolidinone neat as the solvent, other solvents which can be employed include various ethers, chlorinated hydrocarbons, dipolar aprotic solvents such as DMF, lower alkyl nitriles such as acetonitrile, aromatic hydrocarbons, and lower dialkyl ketones such as acetone. In addition to potassium silanolate, other catalysts which can be employed include other-metal silanolates, metal alkoxides, various metal and quaternary ammonium fluorides such as KF, CsF, nBu 4 N + F - , etc. The temperature can vary from 0° C. to 250° C. and the preferred oxazolidinone is 3-trimethylsilyl-2-oxazolidinone. The use of potassium trimethylsilanolate and 3-tri-R-silyl-2-oxazolidinone is a particularly novel feature of the present process.
In Step 4 of Chart I suitable solvents include water, lower alcohols, ethers, and lower alkyl organic acids such as acetic acid and the temperature can vary from 0° C. to 120° C. Suitable catalysts include mineral acids, strong organic acids such as trifluoroacetic acid, and those noted as suitable for Step 3.
In each of Steps 5 and 6 of Chart I, suitable solvents include lower alkyl organic acids and lower alkyl alcohols and acids can be mineral acids but preferably hydrobromic acid.
Chart I also depicts Steps 7 and 8 which represent an alternative method to prepare the chiral compound of Formula I. The oxirane intermediate from Step 2 is reacted with aziridine in an alcoholic solvent. The resulting chiral aziridine intermediate is ring opened with mineral acid in an organic solvent, preferably by hydrobromic acid in acetone. ##STR9##
(R) 3 Si=tri-R-silyl, preferably trimethylsilyl
The novel chiral compounds of Formula I are useful as chemosensitizers or radiosensitizers in patients having cancer. Thus, the compounds of Formula I have utility in patients having cancer which is sensitive to radiation or chemotherapy and are typically administered to said patients prior to being subjected to irradiation of the cancer or being administered chemotherapy. The manner of formulating the compounds of Formula I and the dosage amount of compound to be employed is as described in U.S. Pat. Nos. 5,098,921, 4,954,515 and 4,241,060, and in particular, column 5, line 36 to column 6, line 35 of U.S. Pat. No. 4,241,060, which portion is incorporated herein by reference.
It has been found that the (R)-enantiomer of the compounds of Formula I are particularly useful in that they are substantially devoid of emetic side effects. To illustrate this particular unique utility of the (R)-enantiomers, studies were carried out in beagle dogs on the (R)-enantiomer of a compound of Formula I where X is bromine as follows.
EMESIS STUDIES
Beagle dogs (approximately 10 kg body weight) were treated intravenously with a 10-minute infusion of 20 mL of the test compound prepared in sodium lactate buffer, pH 4.0. Dogs were scored over a 6-hour postdosing period for both the number of emetic episodes and the relative volume. Antiemetic therapy consisted of a 5-minute infusion of ondansetron, administered at a dose of 0.3 mg/kg 30 minutes prior to treatment with the nitroimidazole. The ED 50 value (expressed in mg/kg) is equivalent to the threshold dose at which 50% of the animals exhibited an emetic response.
MOUSE TOXICITY STUDIES
B 6 C 3 F 1 mice were treated with varying doses of test agent by either intraperitoneal, intravenous, or oral administration. Mice were observed for 14 days, noting clinical signs of toxicity and lethality. The maximum tolerated dose was established as the dose equal to or less than the LD 10 as determined from a probit analysis.
RADIOSENSITIZING EFFICACY IN MICE
Clonogenic survival of KHT fibrosarcomas was determined in assays employing B 6 C 3 F 1 mice. Tumors were implanted subcutaneously by trocar. Nine days postimplantation, when tumors ranged from 200 to 400 mg in size, mice were treated IP with a range of drug doses including the maximum tolerated dose of the test agent. Thirty minutes later mice received whole body irradiation at a dose of 10 Gray, delivered at a rate of 2 Gray/minute with a 320 kV x-ray machine. Twenty-four hours after treatment, animals were sacrificed, and tumors were excised. Tumors were enzymatically digested to give single cell suspensions prior to plating for cell survival by clonogenic assay.
Tumor growth delay was assessed in B 6 C 3 F 1 mice implanted IM with 5×10 5 SCC7 carcinoma tumor cells. On Days 10 through 13 post tumor implantation, mice were treated every 12 hours with the maximum tolerated dose of test agent (determined from a 10-day multiple treatment schedule). Thirty minutes later, mice were irradiated at the tumor site with a 2.5 Gray dose of x-rays. Upon completion of this 8 fraction protocol, tumor growth was monitored daily.
Results of the above tests on the racemic mixture, the (S) and the (R) isomers are shown in the following table. Although the activity and toxicity of the chiral compounds are comparable to the racemic mixture, the (R) isomer surprisingly shows significantly less emesis than the (S) isomer or the mixture.
______________________________________Comparison of Formula I Isomers (R/S) (S) (R)______________________________________ ToxicityLD.sub.10 (mg/kg) IP 540 850 850 IV ND 900 900 PO 1000 1100 1100 EfficacyExcision (250 mg/kg).sup.a IP 14 11 11(% control)Growth Delay.sup.b Fold IP 1.8 1.8 2.1Enhancement Emesis (Dogs)ED.sub.50 (mg/kg) IV ˜8 4 12 (6-12)______________________________________ .sup.a KHT fibrosarcoma .sup.b SCC7 carcinoma
The following illustrate in more detail the preparation of the chiral compounds of Formula I where X is bromine.
EXAMPLE 1
(S)-(-)-5-[[(2-Bromoethyl)amino]methyl]-2-nitro-1H-imidazole-1-ethanol, monohydrobromide
(a) (R)-(-)-α-(Chloromethyl)-2-nitro-1H-imidazole-1-ethanol
A stirred suspension of 63.4 g (561 mmole ) of 2-nitroimidazole, 9.1 g (28.1 mole) of anhydrous cesium carbonate, and 1.1 L of absolute ethanol maintained under nitrogen at room temperature is treated with 57 mL (729 mole) of (R)-(-)-epichlorohydrin. The mixture is heated to gentle reflux for 2 hours. The hot solution is filtered through a preheated pad of ethanol-moistened Celite®, the pad is washed with a little ethanol, and the filtrate is diluted with 170 mL of hexane. The filtrate is cooled at 0°-5° C. for 1 day. The resultant crystals are collected by filtration, washed with 120 mL ethyl acetate: diethyl ether (1:1 ) , and dried to give 46.7 g of product as tan needles, mp 126.5°-128° C., 93.9% pure by HPLC.
The mother liquor is concentrated to a solid residue that is suspended in 500 mL of ethyl acetate. The suspension is heated to boiling then filtered hot through preheated moist Celite. The filtrate is maintained at room temperature for 3 hours, then at 0°-5° C. for 35 hours. The resultant crystals are collected by filtration as above to give 31.9 g of a second crop, mp 127°-128.5° C., 97.4% pure by HPLC.
The mother liquor is further processed as above to give 9.2 g of a third crop of less pure product, mp 124°-127° C.
A 1.5-g sample of second crop product is dissolved in 30 mL of boiling ethyl acetate. The solution is treated with charcoal, filtered hot, then maintained first at room temperature for 16 hours then at 0°-5° C. for 48 hours. The resultant crystals are processed as above to give 0.49 g of product as light yellow plates, mp 128°-129° C.; [α] D 25 =-2.57° [cl, methanol].
Alternatively, a mixture of 0.42 g (3.7 mmole) of 2-nitroimidazole, 85 mg (0.62 mole) of anhydrous potassium carbonate, and 5 mL of (R)-(-)-epichlorohydrin is refluxed for 10 minutes then filtered while hot. The filtrate is concentrated and cooled to give a solid. Crystallization from ethanol and further processing as above gives 0.56 g of the product.
(b) (R)-(+)-2-Nitro-1-(2-oxiranylmethyl)-1H-imidazole
Reaction of 40.2 g (196 mole) of (R)-(-)-α-(chloromethyl)-1H-imidazole, 400 mL of 10% aqueous sodium hydroxide, and 400 mL of dichloromethane as described in Example 2 (b) below gives 29.6 g of product, mp 42°-44° C. Purification of a 1.35-g portion of product as described in Example 2(b) below gives 822 mg of product, mp 43°-44° C., 99.9% pure by HPLC; [α] D 25 =+84.95° [cl, methanol].
Alternatively, reaction of (R)-(-)-α-(chloromethyl)-1H-imidazole with 10% aqueous sodium hydroxide as described in Example 2(b) below gives the product.
(c) (R)-3-[3-(2-Nitro-1H-imidazol-1-yl)-2-[(trimethylsilyl)oxypropyl]-2-oxazolidinone
Reaction of 8.46 g (50 mole) of (R)-(+)-2-nitro-1-(2-oxiranylmethyl)-1H-imidazole, 9.4 mL (59.8 mmole) of 3-trimethylsilyl-2-oxazolidinone, and 64 mg of potassium trimethylsilanolate followed by workup as described in Example 2(c) below gives 8.04 g of pure product, mp 98°-100° C.; [α] D 25 -14.54° [cl, methanol].
(d) (R)-3-[2-Hydroxy-3-(2-nitro-1H-imidazol-1-yl)propyl]-2-oxazolidinone
Reaction of 493 mg of (R)-3-[3-(2-nitro-1H-imidazol-1-yl )-2-[(trimethylsilyl)oxy]propyl]-2-oxazolidinone with 3 mL of 1:1 methanol:glacial acetic acid as described in Example 2(d) below gives 40 mg of product, mp 136°-137° C., 98% pure by HPLC; [α] D 25 =+5.80° [cl, methanol].
(e) (S)-(+)-α-(1-Aziridinylmethyl)-2-nitro-1H-imidazole-1-ethanol
A solution of 0.3 g (1.8 mole) of (R)-(+)-2-nitro-1-(2-oxiranylmethyl)-1H-imidazole, 0.24 g (5.4 mmole) of 1H-aziridine, and 3.5 mL of 99:1 absolute ethanol:triethylamine is heated at reflux for 10 minutes, cooled, and concentrated. The residue is crystallized from 99:1 absolute ethanol:triethylamine to give 0.22 g of product, mp 118.5°-120° C. [α] D 24 =+23.5° [C0.98, chloroform].
(f) (S)-(-)-α-[[(2-Bromoethyl)amino]methyl]-2-nitro-1H-imidazole-1-ethanol, monohydrobromide
A mixture of 257 mg (1 mole) of (R)-3-[2-hydroxy-3-(2-nitro-1H-imidazol-1-yl )propyl]-2-oxazolidinone and 1 mL of 31% hydrogen bromide in acetic acid is stirred at room temperature for 7 days. The precipitated solids are collected by filtration, washed successively with 10 mL of 2:1 diethyl ether:2-propanol then 10 mL of diethyl ether, and air dried to leave 385 mg of product. The product is dissolved in 2 mL of hot methanol and the solution is stored at 25° C. for 3 hours, then at 0°-5° C. for 19 hours. The solids are collected by filtration, washed with 5 mL of 1:1 diethyl ether:ethanol, and dried at 40° C./200 mm/15 hours to give 209 mg of pure product as the monohydrobromide salt, mp 153°-154.5° C. (decomposition), 99.3% pure by HPLC.
Alternatively, reaction of 28.11 g (85.6 mmole) of (R)-3-[3-(2-nitro-1H-imidazol-1 -yl)-2[(trimethylsilyl)oxy]propyl]2-oxazolidinone, synthesized as described in Example 1(c), with 142 mL of 31% hydrogen bromide in acetic acid at room temperature for 4 days followed by workup as described in Example 2(f) below gives 18.12 g of pure product as the monohydrobromide salt, mp 154°-155.5° C. (decomposition), 100% optically pure by chiral HPLC; [α] D 25 =-6.94° (cl, methanol)
In another alternate procedure, treatment of S-(+)-α-(1-aziridinylmethyl)-2-nitro-1H-imidazole-1-ethanol, synthesized as described in Example 1(e), with aqueous hydrogen bromide in acetone, as described in The journal of Medicinal Chemistry 33, 2608 (1990) gives the product, mp 148°-149° C. (decomposition), 97.1% optically pure by chiral HPLC.
EXAMPLE 2
R-(+)-α-[[(2-Bromoethyl)amino]methyl]-2-nitro-1H-imidazole-1-ethanol, monohydrobromide
(a) (S)-(+)-α-(Chloromethyl)-2-nitro-1H-imidazole-1-ethanol
Reaction of a mixture of 75.6 g (669 mmole) of 2-nitroimidazole, 68 mL (869 mmole) of (S)-(+)-epichlorohydrin, 10.9 g (33.5 mmole) of anhydrous cesium carbonate, and 1.3 L of absolute ethanol as described in Example 1 gives 101.5 g of product, 92.6% pure by HPLC. A 9.87 g sample is recrystallized from 195 mL of ethyl acetate to give 7.45 g of pure product, mp 128°-129° C.; [α] D 25 =+2.39° [cl, methanol].
Alternatively, reaction of 2-nitroimidazole, anhydrous potassium carbonate, and (S)-(+)-epichlorohydrin as described in Example 1(a) gives the product.
(b) (S)-(-)-2-Nitro-1-(2-oxiranylmethyl)-1H-imidazole
To a vigorously stirring ice-cold suspension of 100.5 g (489 mmole) of (S)-(+)-α-(chloromethyl)-2-nitro-1H-imidazole-1-ethanol in 1 L of dichloromethane is added over 1 minute 1 L of 10% aqueous sodium hydroxide. The biphasic mixture is stirred for 7.5 hours at 0°-5° C., then diluted with 500 mL each of chloroform and water. The phases are separated and the aqueous phase is extracted three times with 200 mL portions of chloroform. The combined organic phases are dried over magnesium sulfate and concentrated to leave 71.1 g of a yellow oil that crystallizes upon prolonged storage at 0°-5° C. The crystals are dried at 0.05 m/25° C./8 hours to give 69.1 g of product, mp 42°-43° C., 98.4% pure by HPLC.
A portion (1.14 g) of the product is dissolved in 20 mL of ethyl acetate and the solution is loaded onto a silica gel (230-400 mesh) column (4×13 cm). The column is eluted with 1:1 ethyl acetate: cyclohexane. Pure product fractions are combined and evaporated to a solid that is crystallized from 14 mL of 5.2 hexane:ethyl acetate. The solution is kept at -5° to 0° C. for 6 hours and the solids are collected by filtration, washed with 20 mL of diethyl ether, and dried at 0.025 m/25° C. to give 681 mg of product as pale yellow crystals, mp 43°-44° C., 99% pure by HPLC; [α] D 25 =-82.18° [cl, methanol].
Alternatively, reaction of 0.56 g of (S)-(+)-α-(chloromethyl)-2-nitro-1H-imidazole-1-ethanol with 3 mL of 10% aqueous sodium hydroxide at 25° C. for 30 minutes followed by further processing as above gives 0.3 g of the product.
(c) (S)-3-[3-(2-Nitro-1H-imidazol-1-yl)-2-[(trimethylsiyl)oxy]propyl]-2-oxazolidinone
Under a brisk stream of dry nitrogen, a vigorously stirring mixture of 40.3 mL (256 mole) of 3-trimethylsilyl-2-oxazolidinone and 274 mg (2.1 mole) of potassium trimethylsilanolate is heated to 95° C. To the solution is added over 10 minutes a solution of 36.15 g (214 mole) of (S)-(-)-2-nitro-1-(2-oxiranylmethyl)-1H-imidazole in 26 mL of dry tetrahydrofuran during which an opening in the flask allows evaporation of solvent. The addition funnel is rinsed with 5 mL of solvent, and the flask is kept open for an additional 15 minutes. After heating at 95° C. for a total of 1.5 hours, 3.4 mL of additional 3-trimethylsilyl-2-oxazolidinone is added to the solution. The mixture is heated for an additional 1.5 hours then concentrated at 0.8 mm/50° C./16 hours to give an oil that is dissolved in 100 mL of 2:1 ethyl acetate:cyclohexane. The solution is loaded onto a column containing an 8×16 cm pad of silica gel (230-400 mesh). The column is eluted with ˜5 L of 2:1 ethyl acetate: cyclohexane. Product fractions are combined and concentrated first at 20 ram, then at 0.8 mm to give 71.45 g of an oil that solidifies on standing. The solids are diluted with 200 mL of tert-butyl methyl ether, and the suspension is refluxed for 45 minutes, cooled, and filtered. The solids are washed sparingly with tert-butyl methyl ether and dried to leave 37.18 g of pure product as a light yellow solid, mp 98°-100° C.; [α] D 25= +15.4° [cl, methanol].
The tert-butyl methyl ether filtrate is concentrated to leave ˜30 g of a viscous oil that is dissolved in 100 mL of 1:1 ethyl acetate:cyclohexane. The solution is loaded onto an 8×16 cm pad of silica gel as above and the column is eluted with 1:1 ethyl acetate: cyclohexane until pure product appears. The column is then eluted with ˜3 L of 2:1 ethyl acetate: cyclohexane. Pure product fractions are combined and concentrated as above to leave 13 g of a sticky solid that is triturated in 1:1 diethyl ether:ethyl acetate to leave 5.67 g of a second crop, mp 95°-98° C., after drying.
(d) (S)-3-[2-Hydroxy-3-(2-nitro-1H-imidazol-1-yl)propyl]-2-oxazolidinone
A solution of 10.51 g (32 mole) of (S)-3-[3-(2-nitro-1H-imidazol-1-yl)-2-[(trimethylsilyl)oxy]propyl]-2-oxazolidinone and 32 mL of 1:1 methanol:glacial acetic acid is stirred at 25° C. for 16 hours during which a precipitate forms. The suspension is diluted with 30 mL of absolute ethanol, and the solids are collected by filtration, washed with ethanol and dried to give 6.49 g of a pure white solid, mp 134°-136° C., 98.5 % optically pure by chiral HPCL; [α] D 25 =-5.97° [cl, methanol].
The filtrate is concentrated to near dryness and the solids are dissolved in methanol. The solution is decolorized with charcoal, then filtered through a pad of silica gel (230-400 mesh). The filtrate volume is reduced to 20 mL and the solution is refrigerated overnight. The solids are collected by filtration, then dissolved in ˜10 mL of methanol. The solution is refrigerated for 3 hours and the solids are collected by filtration, washed with methanol, and dried to leave a second crop as a light yellow solid, mp 134°-136° C. The combined filtrates from the above two crystallizations are concentrated to a solid that is crystallized from methanol as above to give a third crop of product, mp 134°-136° C. The second and third crops are combined and dried to leave 1.18 g of product, 100% optically pure by chiral HPLC; [α] D 25 -5.92 [cl, methanol].
(e) (R)-(-)-α-(1-Aziridinylmethyl)-2-nitro-1H-imidazole-1-ethanol
Reaction of (S)-(-)-2-nitro-1-(2-oxiranylmethyl)-1H-imidazole with 1H-aziridine as described in Example 1(e) gives the product, mp 119.5°-121° C. [α] D 24 -28.7° [cl. 15, chloroform].
(f) (R)-(+)-α-[[(2-Bromoethyl)amino]methyl]-2-nitro-1H-imidazole-1-ethanol, monohydrobromide
A mixture of 8.5 g (33.2 mmole) of (S)-3-[2-hydroxy-3-(2-nitro-1H-imidazol-1-yl)propyl]-2-oxazolidinone and 51 mL of 31% hydrogen bromide in acetic acid is stirred at room temperature for days. The precipitated solids are collected by filtration, washed successively with 70 mL of 1 diethyl ether:2-propanol then 100 mL of diethyl ether, and air dried to leave 11.8 g of product, mp 149°-151° C. (decomposition). The product is dissolved in 100 mL of hot methanol, the solution filtered through Celite, and the filtrate stored at 25° C. for 6 hours then at 0°-5° C. for 8 hours. The solids are collected by filtration, washed with 30 mL of 1:1 diethyl ether:methanol, and dried at 55° C./150 mm/15 hours to give 7 g of pure product as the monohydrobromide salt, mp 154°-156° C. (decomposition), 100% optically pure by chiral HPLC; [α] D 25 =+5.57° [cl, methanol].
Alternatively, to an ice-cold solution of 160 mL of 31% hydrogen bromide in acetic acid was added 31.2 g (95 mmole) of (S)-3-[3-(2-nitro-1H-imidazol-1-yl)-2-[(trimethylsilyl)oxy]propyl]-2-oxazolidinone, synthesized as described in Example 2(c), and the solution is allowed to slowly warm to 25° C. then stirred for 23.5 hours. The solids are collected by filtration, washed with 100 mL of 2:1 diethyl ether:2-propanol, and dried to leave 28.85 g of first crop material. The filtrate is poured slowly into a rapidly stirring solution of 1.2 L of 2:1 diethyl ether:2-propanol. The precipitated solids are collected by filtration, washed with ˜200 mL of 2:1 diethyl ether:2-propanol, then dissolved in a mixture of 80 mL of 1:1 31% hydrogen bromide in acetic acid: 2-propanol. The solution is stirred at 25° C. for 24 hours and the solids are collected by filtration then processed as above to leave 5.35 g of a second crop. The crops are combined and dissolved in 280 mL of hot methanol. The solution is maintained at 25° C. for 2 hours, then refrigerated for 4 hours. The solids are collected by filtration, washed with methanol, and dried to leave 17.62 g of product as the monohydrobromide salt, mp 157°-159° C. (decomposition), 100% optically pure by chiral HPLC; [α] D 25 =+5.55° [cl, methanol].
The filtrate is concentrated to a solid that is crystallized in ˜60 mL of methanol as above to leave 3.8 g of second crop material, mp 152°-154° C. (decomposition). Further processing of the filtrate affords 1.5 g of third crop and 0.5 g of fourth crop materials, mp 145°-150° C. (decomposition). The second through fourth crops are combined and crystallized in 60 mL of hot methanol, with cooling at -20° C. for 7 hours, and further processing as above to give 4.59 g of product, 100% optically pure by chiral HPLC; [α] D 25 =+5.71° [cl, methanol].
In another alternate procedure, treatment of (R)-(-)-α-(1-aziridinylmethyl)-2-nitro-1H-imidazole-1-ethanol, synthesized as described in Example 2(e), with aqueous hydrogen bromide in acetone, as described in The Journal of Medicinal Chemistry, 33, 2608 (1990), gives the product, mp 149°-150.5° C. (decomposition), 99.3% optically pure by chiral HPLC. | Chiral compounds useful as radiosensitizers or chemosensitizers having the formula ##STR1## wherein X is halogen or ##STR2## intermediates used to prepare these compounds, and a novel process to prepare these compounds are described. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is claims priority to U.S. Provisional Application Ser. No. 60/291,215 of Fei Mao, filed on May 15, 2001 and entitled “Biosensor Membranes Composed of Polyvinylpyridines”, which is incorporated herein in its entirety by this reference.
FIELD OF THE INVENTION
[0002] This invention generally relates to an analyte-flux-limiting membrane. More particularly, the invention relates to such a membrane composed of polymers containing heterocyclic nitrogens. The membrane is a useful component in biosensors, and more particularly, in biosensors that can be implanted in a living body.
BACKGROUND OF THE INVENTION
[0003] Enzyme-based biosensors are devices in which an analyte-concentration-dependent biochemical reaction signal is converted into a measurable physical signal, such as an optical or electrical signal. Such biosensors are widely used in the detection of analytes in clinical, environmental, agricultural and biotechnological applications. Analytes that can be measured in clinical assays of fluids of the human body include, for example, glucose, lactate, cholesterol, bilirubin and amino acids. The detection of analytes in biological fluids, such as blood, is important in the diagnosis and the monitoring of many diseases.
[0004] Biosensors that detect analytes via electrical signals, such as current (amperometric biosensors) or charge (coulometric biosensors), are of special interest because electron transfer is involved in the biochemical reactions of many important bioanalytes. For example, the reaction of glucose with glucose oxidase involves electron transfer from glucose to the enzyme to produce gluconolactone and reduced enzyme. In an example of an amperometric glucose biosensor, glucose is oxidized by oxygen in the body fluid via a glucose oxidase-catalyzed reaction that generates gluconolactone and hydrogen peroxide, whereupon the hydrogen peroxide is electrooxidized and correlated to the concentration of glucose in the body fluid. (Thomé-Duret, V., et al., Anal. Chem. 68, 3822 (1996); and U.S. Pat. No. 5,882,494 of Van Antwerp.) In another example of an amperometric glucose biosensor, the electrooxidation of glucose to gluconolactone is mediated by a polymeric redox mediator that electrically “wires” the reaction center of the enzyme to an electrode. (Csöregi, E., et al., Anal. Chem. 66, 3131 (1994); Csöregi, E., et al., Anal. Chem. 67, 1240 (1995); Schmidtke, D. W., et al., Anal. Chem. 68, 2845 (1996); Schmidtke, D. W., et al., Anal. Chem. 70, 2149 (1998); and Schmidtke, D. W., et al., Proc. Natl. Acad. Sci. U.S.A. 95, 294 (1998).)
[0005] Amperometric biosensors typically employ two or three electrodes, including at least one measuring or working electrode and one reference electrode. In two-electrode systems, the reference electrode also serves as a counter-electrode. In three-electrode systems, the third electrode is a counter-electrode. The measuring or working electrode is composed of a non-corroding carbon or a metal conductor and is connected to the reference electrode via a circuit, such as a potentiostat.
[0006] Some biosensors are designed for implantation in a living animal body, such as a mammalian or a human body, merely by way of example. In an implantable amperometric biosensor, the working electrode is typically constructed of a sensing layer, which is in direct contact with the conductive material of the electrode, and a diffusion-limiting membrane layer on top of the sensing layer. The sensing layer typically consists of an enzyme, an enzyme stabilizer such as bovine serum albumin (BSA), and a crosslinker that crosslinks the sensing layer components. Alternatively, the sensing layer consists of an enzyme, a polymeric mediator, and a crosslinker that crosslinks the sensing layer components, as in the above-mentioned “wired-enzyme” biosensor.
[0007] In an implantable amperometric glucose sensor, the membrane is often beneficial or necessary for regulating or limiting the flux of glucose to the sensing layer. By way of explanation, in a glucose sensor without a membrane, the flux of glucose to the sensing layer increases linearly with the concentration of glucose. When all of the glucose arriving at the sensing layer is consumed, the measured output signal is linearly proportional to the flux of glucose and thus to the concentration of glucose. However, when the glucose consumption is limited by the kinetics of chemical or electrochemical activities in the sensing layer, the measured output signal is no longer controlled by the flux of glucose and is no longer linearly proportional to the flux or concentration of glucose. In this case, only a fraction of the glucose arriving at the sensing layer is consumed before the sensor becomes saturated, whereupon the measured signal stops increasing, or increases only slightly, with the concentration of glucose. In a glucose sensor equipped with a diffusion-limiting membrane, on the other hand, the membrane reduces the flux of glucose to the sensing layer such that the sensor does not become saturated and can therefor operate effectively within a much wider range of glucose concentration.
[0008] More particularly, in these membrane-equipped glucose sensors, the glucose consumption rate is controlled by the diffusion or flux of glucose through the membrane rather than by the kinetics of the sensing layer. The flux of glucose through the membrane is defined by the permeability of the membrane to glucose, which is usually constant, and by the concentration of glucose in the solution or biofluid being monitored. When all of the glucose arriving at the sensing layer is consumed, the flux of glucose through the membrane to the sensing layer varies linearly with the concentration of glucose in the solution, and determines the measured conversion rate or signal output such that it is also linearly proportional to the concentration of glucose concentration in the solution. Although not necessary, a linear relationship between the output signal and the concentration of glucose in the solution is ideal for the calibration of an implantable sensor.
[0009] Implantable amperometric glucose sensors based on the electrooxidation of hydrogen peroxide, as described above, require excess oxygen reactant to ensure that the sensor output is only controlled by the concentration of glucose in the body fluid or tissue being monitored. That is, the sensor is designed to be unaffected by the oxygen typically present in body fluid or tissue. In body tissue in which the glucose sensor is typically implanted, the concentration of oxygen can be very low, such as from about 0.02 mM to about 0.2 mM, while the concentration of glucose can be as high as about 30 mM or more. Without a glucose-diffusion-limiting membrane, the sensor would become saturated very quickly at very low glucose concentrations. The sensor thus benefits from having a sufficiently oxygen-permeable membrane that restricts glucose flux to the sensing layer, such that the so-called “oxygen-deficiency problem,” a condition in which there is insufficient oxygen for adequate sensing to take place, is minimized or eliminated.
[0010] In implantable amperometric glucose sensors that employ wired-enzyme electrodes, as described above, there is no oxygen-deficiency problem because oxygen is not a necessary reactant. Nonetheless, these sensors require glucose-diffusion-limiting membranes because typically, for glucose sensors that lack such membranes, the current output reaches a maximum level around or below a glucose concentration of 10 mM, which is well below 30 mM, the high end of clinically relevant glucose concentration.
[0011] A diffusion-limiting membrane is also of benefit in a biosensor that employs a wired-enzyme electrode, as the membrane significantly reduces chemical and biochemical reactivity in the sensing layer and thus reduces the production of radical species that can damage the enzyme. The diffusion-limiting membrane may also act as a mechanical protector that prevents the sensor components from leaching out of the sensor layer and reduces motion-associated noise.
[0012] There have been various attempts to develop a glucose-diffusion-limiting membrane that is mechanically strong, biocompatible, and easily manufactured. For example, a laminated microporous membrane with mechanical holes has been described (U.S. Pat. No. 4,759,828 of Young et al.) and membranes formed from polyurethane are also known (Shaw, G. W., et al., Biosensors and Bioelectronics 6, 401 (1991); Bindra, D. S., et al., Anal. Chem. 63, 1692 (1991); Shichiri, M., et al., Horm. Metab. Res., Suppl. Ser. 20, 17 (1988)). Supposedly, glucose diffuses through the mechanical holes or cracks in these various membranes. Further by way of example, a heterogeneous membrane with discrete hydrophobic and hydrophilic regions (U.S. Pat. No. 4,484,987 of Gough) and homogenous membranes with both hydrophobic and hydrophilic functionalities (U.S. Pat. Nos. 5,284,140 and 5,322,063 of Allen et al.) have been described. However, all of these known membranes are difficult to manufacture and have inadequate physical properties.
[0013] An improved membrane formed from a complex mixture of a diisocyanate, a diol, a diamine and a silicone polymer has been described in U.S. Pat. Nos. 5,777,060 (Van Antwerp), 5,786,439 (Van Antwerp et al.) and 5,882,494 (Van Antwerp). As described therein, the membrane material is simultaneously polymerized and crosslinked in a flask; the resulting polymeric material is dissolved in a strong organic solvent, such as tetrahydroforan (THF); and the resulting solution is applied onto the sensing layer to form the membrane. Unfortunately, a very strong organic solvent, such as THF, can denature the enzyme in the sensing layer and also dissolve conductive ink materials as well as any plastic materials that may be part of the sensor. Further, since the polymerization and crosslinking reactions are completed in the reaction flask, no further bond-making reactions occur when the solution is applied to the sensing layer to form the membrane. As a result, the adhesion between the membrane layer and sensing layer may not be adequate.
[0014] In the published Patent Cooperation Treaty (PCT) Application bearing International Publication No. WO 01/57241 A2, Kelly and Schiffer describe a method for making a glucose-diffusion-limiting membrane by photolytically polymerizing small hydrophilic monomers. The sensitivities of the glucose sensors employing such membranes are widely scattered, however, indicating a lack of control in the membrane-making process. Further, as the polymerization involves very small molecules, it is quite possible that small, soluble molecules remain after polymerization, which may leach out of the sensor. Thus, glucose sensors employing such glucose-diffusion-limiting membranes may not be suitable for implantation in a living body.
SUMMARY OF THE INVENTION
[0015] The present invention is directed to membranes composed of crosslinked polymers containing heterocyclic nitrogen groups, particularly polymers of polyvinylpyridine and polyvinylimidazole, and to electrochemical sensors equipped with such membranes. The membranes are useful in limiting the flux of an analyte to a working electrode in an electrochemical sensor so that the sensor is linearly responsive over a large range of analyte concentrations and is easily calibrated. Electrochemical sensors equipped with membranes of the present invention demonstrate considerable sensitivity and stability, and a large signal-to-noise ratio, in a variety of conditions.
[0016] According to one aspect of the invention, the membrane is formed by crosslinking in situ a polymer, modified with a zwitterionic moiety, a non-pyridine copolymer component, and optionally another moiety that is either hydrophilic or hydrophobic, and/or has other desirable properties, in an alcohol-buffer solution. The modified polymer is made from a precursor polymer containing heterocyclic nitrogen groups. Preferably, the precursor polymer is polyvinylpyridine or polyvinylimidazole. When used in an electrochemical sensor, the membrane limits the flux of an analyte reaching a sensing layer of the sensor, such as an enzyme-containing sensing layer of a “wired enzyme” electrode, and further protects the sensing layer. These qualities of the membrane significantly extend the linear detection range and the stability of the sensor.
[0017] In the membrane formation process, the non-pyridine copolymer component generally enhances the solubility of the polymer and may provide further desirable physical or chemical properties to the polymer or the resulting membrane. Optionally, hydrophilic or hydrophobic modifiers may be used to “fine-tune” the permeability of the resulting membrane to an analyte of interest. Optional hydrophilic modifiers, such as poly(ethylene glycol), hydroxyl or polyhydroxyl modifiers, may be used to enhance the biocompatibility of the polymer or the resulting membrane. In the formation of a membrane of the present invention, the zwitterionic moiety of the polymer is believed to provide an additional layer of crosslinking, via intermolecular electrostatic bonds, beyond the basic crosslinking generally attributed to covalent bonds, and is thus believed to strengthen the membrane.
[0018] Another aspect of the invention concerns the preparation of a substantially homogeneous, analyte-diffusion-limiting membrane that may be used in a biosensor, such as an implantable amperometric biosensor. The membrane is formed in situ by applying an alcohol-buffer solution of a crosslinker and a modified polymer over an enzyme-containing sensing layer and allowing the solution to cure for one to two days. The crosslinker-polymer solution may be applied to the sensing layer by placing a droplet or droplets of the solution on the sensor, by dipping the sensor into the solution, or the like. Generally, the thickness of the membrane is controlled by the concentration of the solution, by the number of droplets of the solution applied, by the number of times the sensor is dipped in the solution, or by any combination of the these factors. Amperometric glucose sensors equipped with diffusion-limiting membranes of the present invention demonstrate excellent stability and fast and linear responsivity to glucose concentration over a large glucose concentration range.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is an illustration of a typical structure of a section of an analyte-diffusion-limiting membrane, according to the present invention.
[0020] FIG. 2A is a schematic, side-view illustration of a portion of a two-electrode glucose sensor having a working electrode, a combined counter/reference electrode, and a dip-coated membrane that encapsulates both electrodes, according to the present invention. FIGS. 2B and 2C are schematic top- and bottom-view illustrations, respectively, of the portion of the glucose sensor of FIG. 2A . Herein, FIGS. 2A , 2 B and 2 C may be collectively referred to as FIG. 2 .
[0021] FIG. 3 is a graph of current versus glucose concentration for sensors having glucose-diffusion-limiting membranes, according to the present invention, and for sensors lacking such membranes, based on average values.
[0022] FIG. 4 is a graph of current output versus time at fixed glucose concentration for a sensor having a glucose-diffusion-limiting membrane, according to the present invention, and for a sensor lacking such a membrane.
[0023] FIG. 5 is a graph of current output versus time at different levels of glucose concentration for sensors having glucose-diffusion-limiting membranes, according to the present invention, based on average values.
[0024] FIG. 6 is a graph of current output versus time at different levels of glucose concentration, with and without stirring, for a sensor having a glucose-diffusion-limiting membrane, according to the present invention, and for a sensor lacking such a membrane.
[0025] FIG. 7A is a graph of current output versus glucose concentration for four separately prepared batches of sensors having glucose-diffusion-limiting membranes, according to the present invention, based on average values. FIGS. 7B-7E are graphs of current output versus glucose concentration for individual sensors in each of the four above-referenced batches of sensors having glucose-diffusion-limiting membranes, respectively, according to the present invention. Herein, FIGS. 7A , 7 B, 7 C, 7 D and 7 E may be collectively referred to as FIG. 7 .
DESCRIPTION OF THE INVENTION
[0026] When used herein, the terms in quotation marks are defined as set forth below.
[0027] The term “alkyl” includes linear or branched, saturated aliphatic hydrocarbons. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl and the like. Unless otherwise noted, the term “alkyl” includes both alkyl and cycloalkyl groups.
[0028] The term “alkoxy” describes an alkyl group joined to the remainder of the structure by an oxygen atom. Examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, tert-butoxy, and the like. In addition, unless otherwise noted, the term ‘alkoxy’ includes both alkoxy and cycloalkoxy groups. The term “alkenyl” describes an unsaturated, linear or branched aliphatic hydrocarbon having at least one carbon-carbon double bond. Examples of alkenyl groups include ethenyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-methyl-1-propenyl, and the like.
[0029] A “reactive group” is a functional group of a molecule that is capable of reacting with another compound to couple at least a portion of that other compound to the molecule. Reactive groups include carboxy, activated ester, sulfonyl halide, sulfonate ester, isocyanate, isothiocyanate, epoxide, aziridine, halide, aldehyde, ketone, amine, acrylamide, thiol, acyl azide, acyl halide, hydrazine, hydroxylamine, alkyl halide, imidazole, pyridine, phenol, alkyl sulfonate, halotriazine, imido ester, maleimide, hydrazide, hydroxy, and photo-reactive azido aryl groups. Activated esters, as understood in the art, generally include esters of succinimidyl, benzotriazolyl, or aryl substituted by electron-withdrawing groups such as sulfo, nitro, cyano, or halo groups; or carboxylic acids activated by carbodiimides.
[0030] A “substituted” functional group (e.g., substituted alkyl, alkenyl, or alkoxy group) includes at least one substituent selected from the following: halogen, alkoxy, mercapto, aryl, alkoxycarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl, —OH, —NH2, alkylamino, dialkylamino, trialkylammonium, alkanoylamino, arylcarboxamido, hydrazino, alkylthio, alkenyl, and reactive groups.
[0031] A “crosslinker” is a molecule that contains at least two reactive groups capable of linking at least two molecules together, or linking at least two portions of the same molecule together. Linking of at least two molecules is called intermolecular crosslinking, while linking of at least two portions of the same molecule is called intramolecular crosslinking. A crosslinker having more than two reactive groups may be capable of both intermolecular and intramolecular crosslinkings at the same time.
[0032] The term “precursor polymer” refers to the starting polymer before the various modifier groups are attached to form a modified polymer.
[0033] The term “heterocyclic nitrogen group” refers to a cyclic structure containing a sp 2 hybridized nitrogen in a ring of the structure.
[0034] The term “polyvinylpyridine” refers to poly(4-vinylpyridine), poly(3-vinylpyridine), or poly(2-vinylpyridine), as well as any copolymer of vinylpyridine and a second or a third copolymer component.
[0035] The term “polyvinylimidazole” refers to poly(1-vinylimidazole), poly(2-vinylimidazole), or poly(4-vinylimidazole).
[0036] A “membrane solution” is a solution that contains all necessary components for crosslinking and forming the membrane, including a modified polymer containing heterocyclic nitrogen groups, a crosslinker and a buffer or an alcohol-buffer mixed solvent.
[0037] A “biological fluid” or “biofluid” is any body fluid or body fluid derivative in which the analyte can be measured, for example, blood, interstitial fluid, plasma, dermal fluid, sweat, and tears.
[0038] An “electrochemical sensor” is a device configured to detect the presence of or measure the concentration or amount of an analyte in a sample via electrochemical oxidation or reduction reactions. Typically, these reactions can be transduced to an electrical signal that can be correlated to an amount or concentration of analyte.
[0039] A “redox mediator” is an electron-transfer agent for carrying electrons between an analyte, an analyte-reduced or analyte-oxidized enzyme, and an electrode, either directly, or via one or more additional electron-transfer agents. A redox mediator that includes a polymeric backbone may also be referred to as a “redox polymer”.
[0040] The term “reference electrode” includes both a) reference electrodes and b) reference electrodes that also function as counter electrodes (i.e., counter/reference electrodes), unless otherwise indicated.
[0041] The term “counter electrode” includes both a) counter electrodes and b) counter electrodes that also function as reference electrodes (i.e., counter/reference electrodes), unless otherwise indicated.
[0042] In general, membrane of the present invention is formed by crosslinking a modified polymer containing heterocyclic nitrogen groups in an alcohol-buffer mixed solvent and allowing the membrane solution to cure over time. The polymer comprises poly(heterocyclic nitrogen-containing constituent) as a portion of its backbone and additional elements, including a zwitterionic moiety, a hydrophobic moiety, and optionally, a biocompatible moiety. The resulting membrane is capable of limiting the flux of an analyte from one space, such as a space associated with a biofluid, to another space, such as space associated with an enzyme-containing sensing layer. An amperometric glucose sensor constructed of a wired-enzyme sensing layer and a glucose-diffusion-limiting layer of the present invention is very stable and has a large linear detection range.
Heterocyclic-Nitrogen Containing Polymers
[0043] The polymer of the present invention has the following general formula, Formula 1a:
[0000]
[0000] wherein the horizontal line represents a polymer backbone; A is an alkyl group substituted with a water soluble group, preferably a negatively charged group, such as sulfonate, phosphate, or carboxylate, and more preferably, a strong acid group such as sulfonate, so that the quaternized heterocyclic nitrogen to which it is attached is zwitterionic; D is a copolymer component of the polymer, as further described below; each of n, l, and p is independently an average number of an associated polymer unit or polymer units shown in the closest parentheses to the left; and q is a number of a polymer unit or polymer units shown in the brackets.
[0044] The heterocyclic nitrogen groups of Formula 1a include, but are not limited to, pyridine, imidazole, oxazole, thiazole, pyrazole, or any derivative thereof. Preferably, the heterocyclic nitrogen groups are independently vinylpyridine, such as 2-, 3-, or 4-vinylpyridine, or vinylimidazole, such as 1-, 2-, or 4-vinylimidazole. More preferably, the heterocyclic nitrogen groups are independently 4-vinylpyridine, such that the more preferable polymer is a derivative of poly(4-vinylpyridine). An example of such a poly(4-vinylpyridine) of the present invention has the following general formula, Formula 1b:
[0000]
[0000] wherein A, D, n, l, p and q are as described above in relation to Formula 1a.
[0045] While the polymer of the present invention has the general Formula 1a or Formula 1b above, it should be noted that when A is a strong acid, such as a stronger acid than carboxylic acid, the D component is optional, such that p may equal zero. Such a polymer of the present invention has the following general formula, Formula 1c:
[0000]
[0000] wherein A is a strong acid and the heterocyclic nitrogen groups, n, l and q are all as described above. Sulfonate and fluorinated carboxylic acid are examples of suitably strong acids. It is believed that when A is a sufficiently strong acid, the heterocyclic nitrogen to which it is attached becomes zwitterionic and thus capable of forming intermolecular electrostatic bonds with the crosslinker during membrane formation. It is believed that these intermolecular electrostatic bonds provide another level of crosslinking, beyond the covalent bonds typical of crosslinking, and thus make the resulting membrane stronger. As a result, when A is a suitably strong acid, the D component, which is often a strengthening component such as styrene, may be omitted from the polymers of Formulas 1a and 1b above. When A is a weaker acid, such that the heterocyclic nitrogen is not zwitterionic or capable of forming intermolecular electrostatic bonds, the polymer of the present invention does include D, as shown in Formulas 1a and 1b above.
[0046] Examples of A include, but are not limited to, sulfopropyl, sulfobutyl, carboxypropyl, and carboxypentyl. In one embodiment of the invention, group A has the formula -L-G, where L is a C2-C12 linear or branched alkyl linker optionally and independently substituted with an aryl, alkoxy, alkenyl, alkynyl, —F, —Cl, —OH, aldehyde, ketone, ester, or amide group, and G is a negatively charged carboxy or sulfonate group. The alkyl portion of the substituents of L have 1-6 carbons and are preferably an aryl, —OH or amide group.
[0047] A can be attached to the heterocyclic nitrogen group via quaternization with an alkylating agent that contains a suitable linker L and a negatively charged group G, or a precursor group that can be converted to a negatively charged group G at a later stage. Examples of suitable alkylating agents include, but are not limited to, 2-bromoethanesulfonate, propanesultone, butanesultone, bromoacetic acid, 4-bromobutyric acid and 6-bromohexanoic acid. Examples of alkylating agents containing a precursor group include, but are not limited to, ethyl bromoacetate and methyl 6-bromohexanoate. The ethyl and methyl ester groups of these precursors can be readily converted to a negatively charged carboxy group by standard hydrolysis.
[0048] Alternatively, A can be attached to the heterocyclic nitrogen group by quaternizing the nitrogen with an alkylating agent that contains an additional reactive group, and subsequently coupling, via standard methods, this additional reactive group to another molecule that contains a negatively charged group G and a reactive group. Typically, one of the reactive groups is an electrophile and the other reactive group is a nucleophile. Selected examples of reactive groups and the linkages formed from their interactions are shown in Table 1.
[0000] TABLE 1 Examples of Reactive Groups and Resulting Linkages First Reactive Group Second Reactive Group Resulting Linkage Activated ester* Amine Amide Acrylamide Thiol Thioether Acyl azide Amine Amide Acyl halide Amine Amide Carboxylic acid Amine Amide Aldehyde or ketone Hydrazine Hydrazone Aldehyde or ketone Hydroxyamine Oxime Alkyl halide Amine Alkylamine Alkyl halide Carboxylic acid Ester Alkyl halide Imidazole Imidazolium Alkyl halide Pyridine Pyridinium Alkyl halide Alcohol/phenol Ether Alkyl halide Thiol Thioether Alkyl sulfonate Thiol Thioether Alkyl sulfonate Pyridine Pyridinium Alkyl sulfonate Imidazole Imidazolium Alkyl sulfonate Alcohol/phenol Ether Anhydride Alcohol/phenol Ester Anhydride Amine Amide Aziridine Thiol Thioether Aziridine Amine Alkylamine Aziridine Pyridine Pyridinium Epoxide Thiol Thioether Epoxide Amine Alkylamine Epoxide Pyridine Pyridinium Halotriazine Amine Aminotriazine Halotriazine Alcohol Triazinyl ether Imido ester Amine Amidine Isocyanate Amine Urea Isocyanate Alcohol Urethane Isothiocyanate Amine Thiourea Maleimide Thiol Thioether Sulfonyl halide Amine Sulfonamide *Activated esters, as understood in the art, generally include esters of succinimidyl, benzotriazolyl, or aryl substituted by electron-withdrawing groups such as sulfo, nitro, cyano, or halo; or carboxylic acids activated by carbodiimides.
By way of example, A may be attached to the heterocyclic nitrogen groups of the polymer by quaternizing the heterocyclic nitrogens with 6-bromohexanoic acid and subsequently coupling the carboxy group to the amine group of 3-amino-1-propanesulfonic acid in the presence of a carbodiimide coupling agent.
[0049] D is a component of a poly(heterocyclic nitrogen-co-D) polymer of Formula 1a or 1b. Examples of D include, but are not limited to, phenylalkyl, alkoxystyrene, hydroxyalkyl, alkoxyalkyl, alkoxycarbonylalkyl, and a molecule containing a poly(ethylene glycol) or polyhydroxyl group. Some poly(heterocyclic nitrogen-co-D) polymers suitable as starting materials for the present invention are commercially available. For example, poly(2-vinylpyridine-co-styrene), poly(4-vinylpyridine-co-styrene) and poly(4-vinylpyridine-co-butyl methacrylate) are available from Aldrich Chemical Company, Inc. Other poly(heterocyclic nitrogen-co-D) polymers can be readily synthesized by anyone skilled in the art of polymer chemistry using well-known methods. Preferably, D is a styrene or a C1-C18 alkyl methacrylate component of a polyvinylpyridine-poly-D, such as (4-vinylpyrine-co-styrene) or poly(4-vinylpyridine-co-butyl methacrylate), more preferably, the former. D may contribute to various desirable properties of the membrane including, but not limited to, hydrophobicity, hydrophilicity, solubility, biocompatibility, elasticity and strength. D may be selected to optimize or “fine-tune” a membrane made from the polymer in terms of its permeability to an analyte and its non-permeability to an undesirable, interfering component, for example.
[0050] The letters n, l, and p designate, respectively, an average number of each copolymer component in each polymer unit. The letter q is one for a block copolymer or a number greater than one for a copolymer with a number of repeating polymer units. By way of example, the q value for a polymer of the present invention may be ≧about 950, where n, l and p are 1, 8 and 1, respectively. The letter q is thus related to the overall molecular weight of the polymer. Preferably, the average molecular weight of the polymer is above about 50,000, more preferably above about 200,000, most preferably above about 1,000,000.
[0051] The polymer of the present invention may comprise a further, optional copolymer, as shown in the following general formula, Formula 2a:
[0000]
[0000] wherein the polymer backbone, A, D, n, 1, p and q are as described above in relation to Formulas 1a-1c; m is an average number of an associated polymer unit or polymer units shown in the closest parentheses to the left; and B is a modifier. When the heterocyclic nitrogen groups are 4-substituted pyridine, as is preferred, the polymer of the present invention is derivative of poly(4-vinylpyridine) and has the general formula, Formula 2b, set forth below.
[0000]
[0052] Further, when A is a suitably strong acid, as described above, the D copolymer is optional, in which case the polymer of the present invention has the general formula, Formula 2c:
[0000]
[0053] In any of Formulas 2a-2c, B is a modifier group that may add any desired chemical, physical or biological properties to the membrane. Such desired properties include analyte selectivity, hydrophobicity, hydrophilicity, elasticity, and biocompatibility. Examples of modifiers include the following: negatively charged molecules that may minimize entrance of negatively charged, interfering chemicals into the membrane; hydrophobic hydrocarbon molecules that may increase adhesion between the membrane and sensor substrate material; hydrophilic hydroxyl or polyhydroxy molecules that may help hydrate and add biocompatibility to the membrane; silicon polymers that may add elasticity and other properties to the membrane; and poly(ethylene glycol) constituents that are known to increase biocompatibility of biomaterials (Bergstrom, K., et al., J. Biomed. Mat. Res. 26, 779 (1992)). Further examples of B include, but are not limited to, a metal chelator, such as a calcium chelator, and other biocompatible materials. A poly(ethylene glycol) suitable for biocompatibility modification of the membrane generally has a molecular weight of from about 100 to about 20,000, preferably, from about 500 to about 10,000, and more preferably, from about 1,000 to about 8,000.
[0054] The modifier B can be attached to the heterocyclic nitrogens of the polymer directly or indirectly. In direct attachment, the heterocyclic nitrogen groups may be reacted with a modifier containing an alkylating group. Suitable alkylating groups include, but are not limited to, alkyl halide, epoxide, aziridine, and sulfonate esters. In indirect attachment, the heterocyclic nitrogens of the polymer may be quaternized with an alkylating agent having an additional reactive group, and then attached to a molecule having a desired property and a suitable reactive group.
[0055] As described above, the B-containing copolymer is optional in the membrane of the present invention, such that when m of Formula 2a-2c is zero, the membrane has the general formula of Formula 1a-1c, respectively. The relative amounts of the four copolymer components, the heterocyclic nitrogen group containing A, the optional heterocyclic nitrogen group containing B, the heterocyclic nitrogen group, and D, may be expressed as percentages, as follows: [n/(n+m+l+p)]×100%, [m/(n+m+l+p)]×100%, [l/(n+m+l+p)]×100%, and [p/(n+m+l+p)]×100%, respectively. Suitable percentages are 1-25%, 0-15% (when the B-containing heterocyclic nitrogen group is optional) or 1-15%, 20-90%, and 0-50% (when D is optional) or 1-50%, respectively, and preferable percentages are 5-20%, 0-10% (when the B-containing heterocyclic nitrogen group is optional) or 1-10%, 60-90%, and 5-20%, respectively.
[0056] Specific examples of suitable polymers have the general formulas, Formulas 3-6, shown below.
[0000]
EXAMPLES OF SYNTHESES OF POLYVINYLPYRIDINE POLYMERS
[0057] Examples showing the syntheses of various polyvinylpyridine polymers according to the present invention are provided below. Numerical figures provided are approximate.
Example 1
Synthesis of a Polymer of Formula 3
[0058] By way of illustration, an example of the synthesis of a polymer of Formula 3 above, is now provided. A solution of poly(4-vinylpyridine-co-styrene) (10% styrene content) (20 g, Aldrich) in 100 mL of dimethyl formamide (DMF) at 90° C. was stirred and 6-bromohexanoic acid (3.7 g) in 15-20 mL of DMF was added. The resulting solution was stirred at 90° C. for 24 hours and then poured into 1.5 L of ether, whereupon the solvent was decanted. The remaining, gummy solid was dissolved in MeOH (150-200 mL) and suction-filtered through a medium-pore, fritted funnel to remove any undissolved solid. The filtrate was added slowly to rapidly stirred ether (1.5 L) in a beaker. The resulting precipitate was collected by suction filtration and dried at 50° C. under high vacuum for 2 days. The polymer had the following parameters: [n/(n+l+p)]×100%≈10%; [l/(n+l+p)]×100%≈80%; and [p/(n+l+p)]×100%≈110%.
Example 2
Synthesis of a Polymer of Formula 5
[0059] By way of illustration, an example of the synthesis of a polymer of Formula 5 above, is now provided. A solution of poly(4-vinylpyridine-co-styrene) (10% styrene) (20 g, Aldrich) in 100 mL of anhydrous DMF at 90° C. was stirred, methanesulfonic acid (˜80 mg) was added, and then 2 g of methoxy-PEG-epoxide (molecular weight 5,000) (Shearwater Polymers, Inc.) in 15-20 mL of anhydrous DMF was added. The solution was stirred at 90° C. for 24 hours and 1,3-Propane sultone (2.32 g) in 10 mL of anhydrous DMF was added. The resulting solution was continuously stirred at 90° for 24 hours, and then cooled to room temperature and poured into 800 mL of ether. The solvent was decanted and the remaining precipitate was dissolved in hot MeOH (˜200 mL), suction-filtered, precipitated again from 1 L of ether, and then dried at 50° C. under high vacuum for 48 hours. The resulting polymer has the following parameters: [n/(n+m+l+p)]×100%≈10%; [m/(n+m+l+p)]×100%≈10%; [l/(n+m+l+p)]×100%≈70%; and [p/(n+m+l+p)]×100%≈10%.
Example 3
Synthesis of a Polymer Having a Polyhydroxy Modifier B
[0060] By way of illustration, an example of the synthesis of a polymer having a polyhydroxy modifier B, as schematically illustrated below, is now provided. Various polyhydroxy compounds are known for having biocompatibility properties. (U.S. Pat. No. 6,011,077.) The synthesis below illustrates how a modifier group having a desired property may be attached to the polymer backbone via a linker.
[0000]
[0000] 1,3-propane sultone (0.58 g, 4.8 mmoles) and 6-bromohexanoic acid (1.85 g, 9.5 mmoles) are added to a solution of poly(4-vinylpyridine-co-styrene) (˜10% styrene) (10 g) dissolved in 60 mL of anhydrous DMF. The resulting solution is stirred at 90° C. for 24 hours and then cooled to room temperature. O—(N-succinimidyl)-N,N,N′,N′-tetramethyl-uronium tetrafluoroborate (TSTU) (2.86 g, 9.5 mmoles) and N,N-diisopropylethylamine (1.65 mL, 9.5 mmoles) are then added in succession to the solution. After the solution is stirred for 5 hours, N-methyl-D-glucamine (2.4 g, 12.4 mmoles) is added and the resulting solution is stirred at room temperature for 24 hours. The solution is poured into 500 ml of ether and the precipitate is collected by suction filtration. The collected precipitate is then dissolved in MeOH/H 2 O and the resulting solution is subjected to ultra membrane filtration using the same MeOH/H 2 O solvent to remove small molecules. The dialyzed solution is evaporated to dryness to give a polymer with the following parameters: [n/(n+m+l+p)]×100%≈10%; [m/(n+m+l+p)]×100%≈10%; [l/(n+m+l+p)]×100%≈70%; and [p/(n+m+l+p)]×100%≈10%.
Crosslinkers
[0061] Crosslinkers of the present invention are molecules having at least two reactive groups, such as bi-, tri-, or tetra-functional groups, capable of reacting with the heterocyclic nitrogen groups, pyridine groups, or other reactive groups contained on A, B or D of the polymer. Preferably, the reactive groups of the crosslinkers are slow-reacting alkylating groups that can quaternize the heterocyclic nitrogen groups, such as pyridine groups, of the polymer. Suitable alkylating groups include, but are not limited to, derivatives of poly(ethylene glycol) or polypropylene glycol), epoxide (glycidyl group), aziridine, alkyl halide, and sulfonate esters. Alkylating groups of the crosslinkers are preferably glycidyl groups. Preferably, glycidyl crosslinkers have a molecular weight of from about 200 to about 2,000 and are water soluble or soluble in a water-miscible solvent, such as an alcohol. Examples of suitable crosslinkers include, but are not limited to, poly(ethylene glycol) diglycidyl ether with a molecular weight of about 200 to about 600, and N,N-diglycidyl-4-glycidyloxyaniline.
[0062] It is desirable to have a slow crosslinking reaction during the dispensing of membrane solution so that the membrane coating solution has a reasonable pot-life for large-scale manufacture. A fast crosslinking reaction results in a coating solution of rapidly changing viscosity, which renders coating difficult. Ideally, the crosslinking reaction is slow during the dispensing of the membrane solution, and accelerated during the curing of the membrane at ambient temperature, or at an elevated temperature where possible.
Membrane Formation and Sensor Fabrication
[0063] An example of a process for producing a membrane of the present invention is now described. In this example, the polymer of the present invention and a suitable crosslinker are dissolved in a buffer-containing solvent, typically a buffer-alcohol mixed solvent, to produce a membrane solution. Preferably, the buffer has a pH of about 7.5 to about 9.5 and the alcohol is ethanol. More preferably, the buffer is a 10 mM (2-(4-(2-hydroxyethyl)-1-piperazine)ethanesulfonate) (HEPES) buffer (pH 8) and the ethanol to buffer volume ratio is from about 95 to 5 to about 0 to 100. A minimum amount of buffer is necessary for the crosslinking chemistry, especially if an epoxide or aziridine crosslinker is used. The amount of solvent needed to dissolve the polymer and the crosslinker may vary depending on the nature of the polymer and the crosslinker. For example, a higher percentage of alcohol may be required to dissolve a relatively hydrophobic polymer and/or crosslinker.
[0064] The ratio of polymer to cross-linker is important to the nature of the final membrane. By way of example, if an inadequate amount of crosslinker or an extremely large excess of crosslinker is used, crosslinking is insufficient and the membrane is weak. Further, if a more than adequate amount of crosslinker is used, the membrane is overly crosslinked such that membrane is too brittle and/or impedes analyte diffusion. Thus, there is an optimal ratio of a given polymer to a given crosslinker that should be used to prepare a desirable or useful membrane. By way of example, the optimal polymer to crosslinker ratio by weight is typically from about 4:1 to about 32:1 for a polymer of any of Formulas 3-6 above and a poly(ethylene glycol) diglycidyl ether crosslinker, having a molecular weight of about 200 to about 400. Most preferably, this range is from about 8:1 to about 16:1. Further by way of example, the optimal polymer to crosslinker ratio by weight is typically about 16:1 for a polymer of Formula 4 above, wherein [n/(n+l+p)]×100%≈10%, [l/(n+l+p)]×100%≈80%, and [p/(n+l+p)]×100%≈10%, or for a polymer of Formula 5 above, wherein [n/(n+m+l+p)]×100%≈10%, [m/(n+m+l+p)]×100%≈10%, [l/(n+m+l+p)]×100%≈70%, [p/(n+m+l+p)]×100%≈10%, and r≈110, and a poly(ethylene glycol) diglycidyl ether crosslinker having a molecular weight of about 200.
[0065] The membrane solution can be coated over a variety of biosensors that may benefit from having a membrane disposed over the enzyme-containing sensing layer. Examples of such biosensors include, but are not limited to, glucose sensors and lactate sensors. (See U.S. Pat. No. 6,134,461 to Heller et al., which is incorporated herein in its entirety by this reference.) The coating process may comprise any commonly used technique, such as spin-coating, dip-coating, or dispensing droplets of the membrane solution over the sensing layers, and the like, followed by curing under ambient conditions typically for 1 to 2 days. The particular details of the coating process (such as dip duration, dip frequency, number of dips, or the like) may vary depending on the nature (i.e., viscosity, concentration, composition, or the like) of the polymer, the crosslinker, the membrane solution, the solvent, and the buffer, for example. Conventional equipment may be used for the coating process, such as a DSG D1L-160 dip-coating or casting system of NIMA Technology in the United Kingdom.
Example of Sensor Fabrication
[0066] Sensor fabrication typically consists of depositing an enzyme-containing sensing layer over a working electrode and casting the diffusion-limiting membrane layer over the sensing layer, and optionally, but preferably, also over the counter and reference electrodes. The procedure below concerns the fabrication of a two-electrode sensor, such as that depicted in FIGS. 2A-2C . Sensors having other configurations such as a three-electrode design can be prepared using similar methods.
[0067] A particular example of sensor fabrication, wherein the numerical figures are approximate, is now provided. A sensing layer solution was prepared from a 7.5 mM HEPES solution (0.5 μL, pH 8), containing 1.7 μg of the polymeric osmium mediator compound L, as disclosed in Published Patent Cooperation Treaty (PCT) Application, International Publication No. WO 01/36660 A2, which is incorporated herein in its entirety by this reference; 2.1 μg of glucose oxidase (Toyobo); and 1.3 μg of poly(ethylene glycol) diglycidyl ether (molecular weight 400). Compound L is shown below.
[0000]
[0000] The sensing layer solution was deposited over carbon-ink working electrodes and cured at room temperature for two days to produce a number of sensors. A membrane solution was prepared by mixing 4 volumes of a polymer of Formula 4 above, dissolved at 64 mg/mL in 80% EtOH/20% HEPES buffer (10 mM, pH 8), and one volume of poly(ethylene glycol) diglycidyl ether (molecular weight 200), dissolved at 4 mg/mL in 80% EtOH/20% HEPES buffer (10 mM, pH 8). The above-described sensors were dipped three times into the membrane solution, at about 5 seconds per dipping, with about a 10-minute time interval between consecutive dippings. The sensors were then cured at room temperature and normal humidity for 24 hours.
[0068] An approximate chemical structure of a section of a typical membrane prepared according to the present invention is shown in FIG. 1 . Such a membrane may be employed in a variety of sensors, such as the two- or three-electrode sensors described previously herein. By way of example, the membrane may be used in a two-electrode amperometric glucose sensor, as shown in FIG. 2A-2C (collectively FIG. 2 ) and described below.
[0069] The amperometric glucose sensor 10 of FIG. 2 comprises a substrate 12 disposed between a working electrode 14 that is typically carbon-based, and a Ag/AgCl counter/reference electrode 16 . A sensor or sensing layer 18 is disposed on the working electrode. A membrane or membrane layer 20 encapsulates the entire glucose sensor 10 , including the Ag/AgCl counter/reference electrode.
[0070] The sensing layer 18 of the glucose sensor 10 consists of crosslinked glucose oxidase and a low potential polymeric osmium complex mediator, as disclosed in the above-mentioned Published PCT Application, International Publication No. WO 01/36660 A2. The enzyme- and mediator-containing formulation that can be used in the sensing layer, and methods for applying them to an electrode system, are known in the art, for example, from U.S. Pat. No. 6,134,461. According to the present invention, the membrane overcoat was formed by thrice dipping the sensor into a membrane solution comprising 4 mg/mL poly(ethylene glycol) diglycidyl ether (molecular weight of about 200) and 64 mg/mL of a polymer of Formula 4 above, wherein [n/(n+l+p)]×100%≈10%; [l/(n+l+p)]×100%≈80%; and [p/(n+l+p)]×100%≈10%, and curing the thrice-dipped sensor at ambient temperature and normal humidity for at least 24 hours, such as for about 1 to 2 days. The q value for such a membrane overcoat may be ≧about 950, where n, l and p are 1, 8 and 1, respectively.
Membrane Surface Modification
[0071] Polymers of the present invention have a large number of heterocyclic nitrogen groups, such as pyridine groups, only a few percent of which are used in crosslinking during membrane formation. The membrane thus has an excess of these groups present both within the membrane matrix and on the membrane surface. Optionally, the membrane can be further modified by placing another layer of material over the heterocyclic-nitrogen-group-rich or pyridine-rich membrane surface. For example, the membrane surface may be modified by adding a layer of poly(ethylene glycol) for enhanced biocompatibility. In general, modification may consist of coating the membrane surface with a modifying solution, such as a solution comprising desired molecules having an alkylating reactive group, and then washing the coating solution with a suitable solvent to remove excess molecules. This modification should result in a monolayer of desired molecules.
[0072] The membrane 20 of the glucose sensor 10 shown in FIG. 2 may be modified in the manner described above.
Experimental Examples
[0073] Examples of experiments that demonstrate the properties and/or the efficacy of sensors having diffusion-limiting membranes according to the present invention are provided below. Numerical figures provided are approximate.
Calibration Experiment
[0074] In a first example, a calibration experiment was conducted in which fifteen sensors lacking membranes were tested simultaneously (Set 1), and separately, eight sensors having diffusion-limiting membranes according to the present invention were tested simultaneously (Set 2), all at 37° C. In Set 2, the membranes were prepared from polymers of Formula 4 above and poly(ethylene glycol) diglycidyl ether (PEGDGE) crosslinkers, having a molecular weight of about 200. In the calibration experiment for each of Set 1 and Set 2, the sensors were placed in a PBS-buffered solution (pH 7) and the output current of each of the sensors was measured as the glucose concentration was increased. The measured output currents (μA for Set 1; nA for Set 2) were then averaged for each of Set 1 and Set 2 and plotted against glucose concentration (mM), as shown in the calibration graph of FIG. 3 .
[0075] As shown, the calibration curve for the Set 1 sensors lacking membranes is approximately linear over a very small range of glucose concentrations, from zero to about 3 mM, or 5 mM at most. This result indicates that the membrane-free sensors are insufficiently sensitive to glucose concentration change at elevated glucose concentrations such as 10 mM, which is well below the high end of clinically relevant glucose concentration at about 30 mM. By contrast, the calibration curve for the Set 2 sensors having diffusion-limiting membranes according to the present invention is substantially linear over a relatively large range of glucose concentrations, for example, from zero to about 30 mM, as demonstrated by the best-fit line (y=1.2502x+1.1951; R 2 ˜0.997) also shown in FIG. 3 . This result demonstrates the considerable sensitivity of the membrane-equipped membranes to glucose concentration, at low, medium, and high glucose concentrations, and of particular relevance, at the high end of clinically relevant glucose concentration at about 30 mM.
Stability Experiment
[0076] In a second example, a stability experiment was conducted in which a sensor lacking a membrane and a sensor having a diffusion-limiting membrane according to the present invention were tested, simultaneously, at 37° C. The membrane-equipped sensor had a membrane prepared from the same polymer and the same crosslinker as those of the sensors of Set 2 described above in the calibration experiment. In this stability experiment, each of the sensors was placed in a PBS-buffered solution (pH 7) having a fixed glucose concentration of 30 mM, and the output current of each of the sensors was measured. The measured output currents (μA for the membrane-less sensor; nA for the membrane-equipped sensor) were plotted against time (hour), as shown in the stability graph of FIG. 4 .
[0077] As shown, the stability curve for the membrane-less sensor decays rapidly over time, at a decay rate of about 4.69% μA per hour. This result indicates a lack of stability in the membrane-less sensor. By contrast, the stability curve for the membrane-equipped sensor according to the present invention shows relative constancy over time, or no appreciable decay over time, the decay rate being only about 0.06% nA per hour. This result demonstrates the considerable stability and reliability of the membrane-equipped sensors of the present invention. That is, at a glucose concentration of 30 mM, while the membrane-less sensor lost sensitivity at a rate of almost 5% per hour over a period of about 20 hours, the membrane-equipped sensor according to the present invention showed virtually no loss of sensitivity over the same period.
Responsivity Experiment
[0078] Ideally, the membrane of an electrochemical sensor should not impede communication between the sensing layer of the sensor and fluid or biofluid containing the analyte of interest. That is, the membrane should respond rapidly to changes in analyte concentration.
[0079] In a third example, a responsivity experiment was conducted in which eight sensors having diffusion-limiting membranes according to the present invention were tested simultaneously (Set 3), all at 37° C. The sensors of Set 3 had membranes prepared from the same polymers and the same crosslinkers as those of the sensors of Set 2 described in the calibration experiment above. In this responsivity experiment, the eight sensors were placed in a PBS-buffered solution (pH 7), the glucose concentration of which was increased in a step-wise manner over time, as illustrated by the glucose concentrations shown in FIG. 5 , and the output current of each of the sensors was measured. The measured output currents (nA) were then averaged for Set 3 and plotted against time (real time, hour:minute:second), as shown in the responsivity graph of FIG. 5 .
[0080] The responsivity curve for the Set 3 sensors having diffusion-limiting membranes according to the present invention has discrete steps that manic the step-wise increases in glucose concentration in a rapid fashion. As shown, the output current jumps rapidly from one plateau to the next after the glucose concentration is increased. This result demonstrates the considerable responsivity of the membrane-equipped sensors of the present invention. The responsivity of these membrane-equipped electrochemical sensors makes them ideal for analyte sensing, such as glucose sensing.
Motion-Sensitivity Experiment
[0081] Ideally, the membrane of an electrochemical sensor should be unaffected by motion or movement of fluid or biofluid containing the analyte of interest. This is particularly important for a sensor that is implanted in a body, such as a human body, as body movement may cause motion-associated noise and may well be quite frequent.
[0082] In this fourth example, a motion-sensitivity experiment was conducted in which a sensor A lacking a membrane was tested, and separately, a sensor B having a diffusion-limiting membrane according to the present invention was tested, all at 37° C. Sensor B had a membrane prepared from the same polymer and the same crosslinker as those of the sensors of Set 2 described in the calibration experiment above. In this experiment, for each of test, the sensor was placed in a beaker containing a PBS-buffered solution (pH 7) and a magnetic stirrer. The glucose concentration of the solution was increased in a step-wise manner over time, in much the same manner as described in the responsivity experiment above, as indicated by the various mM labels in FIG. 6 . The stirrer was activated during each step-wise increase in the glucose concentration and deactivated some time thereafter, as illustrated by the “stir on” and “stir off” labels shown in FIG. 6 . This activation and deactivation of the stirrer was repeated in a cyclical manner at several levels of glucose concentration and the output current of each of the sensors was measured throughout the experiment. The measured output currents (μA for sensor A; nA for sensor B) were plotted against time (minute), as shown in the motion-sensitivity graph of FIG. 6 .
[0083] As shown, the output current for the membrane-less sensor A is greatly affected by the stir versus no stir conditions over the glucose concentration range used in the experiment. By contrast, the output current for sensor B, having diffusion-limiting membranes according to the present invention, is virtually unaffected by the stir versus no stir conditions up to a glucose concentration of about 10 mM, and only slightly affected by these conditions at a glucose concentration of about 15 mM. This result demonstrates the considerable stability of the membrane-equipped sensors of the present invention in both stirred and non-stirred environments. The stability of these membrane-equipped electrochemical sensors in an environment of fluid movement makes them ideal for analyte sensing within a moving body.
Sensor Reproducibility Experiment
[0084] Dip-coating, or casting, of membranes is typically carried out using dipping machines, such as a DSG D1L-160 of NIMA Technology of the United Kingdom. Reproducible casting of membranes has been considered quite difficult to achieve. (Chen, T., et al., In Situ Assembled Mass - Transport Controlling Micromembranes and Their Application in Implanted Amperometric Glucose Sensors , Anal. Chem., Vol. 72, No. 16, Pp. 3757-3763 (2000).) Surprisingly, sensors of the present invention can be made quite reproducibly, as demonstrated in the experiment now described.
[0085] Four batches of sensors (Batches 1-4) were prepared separately according to the present invention, by dipping the sensors in membrane solution three times using casting equipment and allowing them to cure. In each of the four batches, the membrane solutions were prepared from the polymer of Formula 4 and poly(ethylene glycol) digycidyl ether (PEDGE) crosslinker having a molecular weight of about 200 (as in Set 2 and other Sets described above) using the same procedure. The membrane solutions for Batches 1 and 2 were prepared separately from each other, and from the membrane solution used for Batches 3 and 4. The membrane solution for Batches 3 and 4 was the same, although the Batch 3 and Batch 4 sensors were dip-coated at different times using different casting equipment. That is, Batches 1, 2 and 3 were dip-coated using a non-commercial, built system and Batch 4 was dip-coated using the above-referenced DSG D1L-160 system.
[0086] Calibration tests were conducted on each batch of sensors at 37° C. For each batch, the sensors were placed in PBS-buffered solution (pH 7) and the output current (nA) of each of the sensors was measured as the glucose concentration (mM) was increased. For each sensor in each of the four batches, a calibration curve based on a plot of the current output versus glucose concentration was prepared as shown in FIG. 7B (Batch 1: 5 sensors), FIG. 7C (Batch 2: 8 sensors), FIG. 7D (Batch 3: 4 sensors) and FIG. 7E (Batch 4: 4 sensors). The average slopes of the calibration curves for each batch were the following:
[0087] Batch 1: Average Slope=1.10 nA/mM (CV=5%);
[0088] Batch 2: Average Slope=1.27 nA/mM (CV=10%);
[0089] Batch 3: Average Slope=1.15 nA/mM (CV=5%); and
[0090] Batch 4: Average Slope=1.14 nA/mM (CV=7%).
[0000] Further, for each batch, the current output for the sensors in the batch was averaged and plotted against glucose concentration, as shown in FIG. 7A . The average slope for Batches 1-4 was 1.17 nA/mM (CV=7.2%).
[0091] The slopes of the curves within each batch and from batch-to-batch are very tightly grouped, showing considerably little variation. The results demonstrate that sensors prepared according to the present invention give quite reproducible results, both within a batch and from batch-to-batch.
[0092] The foregoing examples demonstrate many of the advantages of the membranes of the present invention and the sensors employing such membranes. Particular advantages of sensors employing the membranes of the present invention include sensitivity, stability, responsivity, motion-compatibility, ease of calibration, and ease and reproducibility of manufacture.
[0093] Various aspects and features of the present invention have been explained or described in relation to beliefs or theories, although it will be understood that the invention is not bound to any particular belief or theory. Various modifications, processes, as well as numerous structures to which the present invention may be applicable will be readily apparent to those of skill in the art to which the present invention is directed upon review of the specification. Although the various aspects and features of the present invention have been described with respect to various embodiments and specific examples herein, it will be understood that the invention is entitled to protection within the full scope of the appended claims. | Novel membranes comprising various polymers containing heterocyclic nitrogen groups are described. These membranes are usefully employed in electrochemical sensors, such as amperometric biosensors. More particularly, these membranes effectively regulate a flux of analyte to a measurement electrode in an electrochemical sensor, thereby improving the functioning of the electrochemical sensor over a significant range of analyte concentrations. Electrochemical sensors equipped with such membranes are also described. | 2 |
BACKGROUND OF THE INVENTION
Electric warp stop-motions are well known in the weaving trade. Their function is to stop the loom when the warp thread breaks. Toward this end, as is well known in the art, as each warp thread leaves the warp beam and passes over the whip roll, it is passed through a drop wire which is an integral part of the electric stop-motion. The electric stop-motion is positioned between the warp beam and the heddles in the harness mechanism which forms the shed. Electric warp stop-motions have long been known and need not be described as the support mechanism of this invention is useful with any desired electric warp stop-motion utilizing drop wires and electrodes.
As is well known throughout the trade, the positioning of the warp stop-motion device is critical to the grain or the appearance of the fabric. It is therefore of great importance to provide means for rapidly and accurately shifting or adjusting the warp stop-motion device longitudinally and laterally of the loom and vertically, as desired. Prior attempts to provide a suitable support for electric warp stop-motion devices are shown in U.S. Pat. No. 2,858,857 issued Nov. 4, 1958 to Jaime Picanol, U.S. Pat. No. 3,421,552 issued Jan. 14, 1969 to Stanley J. Sotek, U.S. Pat. No. 3,584,659 issued June 15, 1971 to Erwin Pfarrwaller, and U.S. Pat. No. 3,358,718 issued Dec. 19, 1967 to Harold J. Bager, et. al.
The support mechanisms of the prior art are satisfactory to permit adjustments of the warp stop-motion device longitudinally and laterally of the loom and also vertically, but the time required to make the adjustments is objectionable and it is objectionable to need to make adjustments after the stop-motion mechanism is moved to work on the loom or replace a warp beam.
In recent years, loom operating speed have increased tremendously and the size of the warp beam has correspondingly increased in order to provide a larger supply of yarn and reduce the number of times the warp beam had to be replaced during operation of the high speed loom.
In certain prior art support mechanisms for electric stop-motion devices it is necessary to remove the stop-motion mechanism in order to replace the new enlarged warp beam and it is consequently necessary to readjust the position of the warp stop-motion mechanism when said mechanism is reinstalled on the loom after the warp beam has been changed. This results in considerable down time for the loom with a consequent loss of production.
SUMMARY OF THE INVENTION
The present invention includes means for quickly and accurately adjusting the position of the warp stop-motion mechanism to any desired location by manipulating it longitudinally, laterally, and vertically relative to the loom. Additionally, the warp stop-motion mechanism is supported by means of the present invention in cantilever fashion from the frame of the loom in such a manner that the stop-motion mechanism may be manually pivoted upwardly and then mechanically held out of the way when desired, as when changing a warp beam of the present large diameter. The support mechanism of the present invention may be manually lowered back into its original optimum operating position automatically without attention by the operator except to tighten the few bolts necessary to hold it in that position during operation of the loom.
It is an object of this invention to provide a support mechanism for electric warp stop-motion mechanisms which supports the stop-motion mechanism in pivoted cantilever fashion from the loom frame, and which includes a positive stop for automatically reestablishing the desired location of the warp stop-motion mechanism after it has been purposefully moved out of the way.
It is a further object of the invention to provide support means for a warp stop-motion mechanism, which support means provides firm rigid support for the elongated and fragile components of the mechanism to restrict vibration and thereby increase its useful life.
It is a still further object of the invention to provide support means for a warp stop-motion, which support means comprises components which are individually replaceable when necessary instead of having to replace the entire support unit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a somewhat schematic perspective view looking at the rear and one side of a weaving loom and illustrating one approximate relative positioning of the warp beam and the electric stop-motion mechanism;
FIG. 2 is an enlarged perspective view, with parts broken away, illustrating the attachment of the support assembly according to the invention on one side of the loom and operatively connected with the electric stop-motion mechanism;
FIG. 3 is a side elevation of the support assembly shown in FIG. 2 in operative position and bearing against the positive stop pin;
FIG. 4 is a view similar to FIG. 3 but showing the support assembly pivoted away from the positive stop pin to elevate the stop-motion device;
FIG. 5 is a top plan view of the support assembly shown in FIG. 2, removed from the loom;
FIG. 6 is a vertical sectional view taken substantially along the line 6--6 in FIG. 2; and
FIG. 7 is a vertical sectional view taken substantially along the line 7--7 in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
Referring more specifically to the drawings, a weaving loom generally designated by the reference numeral 10 includes a frame 11 which supports a warp beam 12 extending transversely across the rear of the loom 10. Individual ends of warp yarn, only one of which is indicated at Y for purposes of illustration, are drawn from the warp beam 12, across a whip roll 19 and through a stop-motion mechanism broadly indicated at 13 enroute to the weaving instrumentalities, not shown, on the loom 10.
The stop-motion mechanism 13 includes a drop wire 14 for each warp yarn Y supported about electrodes 15 and between separator bars 16. The electrodes 15 and separator bars 16 extend transversely across the rear of the loom and are supported between spacer blocks 17, there being a block 17 of desired thickness between adjacent electrodes 15 and separator bars 16 (FIG. 7) to maintain them in desired spaced relation. Each spacer block 17 has an opening 18 therethrough to slidably receive a threaded rod 20 having a free end 21 over which the blocks 17 are threaded preparatory to clamping the electrodes 15 and separator bars 16 between the blocks 17. End blocks 22 are also threaded on the threaded rods 20 to support the outermost and innermost electrodes and separator bars.
A threaded rod 20 is provided at each side of the loom 10 and includes a fixed end 23 received for longitudinal adjustment in a tubular extension 24 of a pivot bracket 25.
It will be understood that the rod 20, tubular extension 24 and pivot bracket 25 are components of a support assembly broadly indicated at 19 and that there is a support assembly 19 of the same instruction on each side of the loom 10 and that the following description of the support assembly 19 illustrated in the drawings on one side of the loom is equally applicable to the support assembly on the other side of the loom.
The support assembly 19 for the stop-motion mechanism 13 comprises an L-shaped angle bracket 26 including a horizontally disposed plate 27 and a vertically disposed plate 28. The horizontal plate 27 has a transversely extending slot 30 through which a bolt 31 loosely passes and is secured to the frame 11 of the loom 10. The vertical plate 28 of bracket 26 has a pair of threaded bores, not shown which threadably engage bolts 31 and 32 extending through vertical slots 33 and 34 in a mounting plate 35. The pivot bracket 25 is journaled on the mounting plate 35 by a pivot pin 36 extending through the axis of the pivot plate 25. The pivot bracket 25 is freely pivotal about pin 36 relative to mounting plate 35, but may be supported in raised position by adjustment of bolts 37 and 38 which loosely penetrate arcuate slots 40 and 41 through pivot bracket 25 and are threadably retained in threaded bores 42 and 43 (FIG. 5) in mounting plate 35. The pivot bracket 25 is primarily supported in its intended operative position by an abutment or stop 44 projecting laterally inwardly from the mounting plate 35 for engagement by the proximal edge 45 of pivot bracket 25 when it is in the operative postion of FIGS. 2 and 3.
The bolts 37 and 38 may be loosened when desired to elevate the stop-motion mechanism 13 and the pivot bracket 25 may be rotated within the limit of the arcuate slots 40, 41 as shown in FIG. 4, after which the bolts 37, 38 may be tightened to retain the threaded rods 20 and the stop-motion mechanism 13 in an elevated position out of the way while work is carried out on the loom as by replacing the warp beam 12. When it is desired to reposition the stop-motion mechanism 13 in its operative position, the bolts 37, 38 are loosened to permit the pivot bracket 25 to rotate to the right in FIGS. 3 and 4 until the edge 45 engages the fixed abutment 44, thereby automatically returning the stop-motion mechanism 13 to its predetermined optimum operating position.
The predetermined optimum operating position of the stop-motion mechanism 13 is achieved through manipulation of the various provisions for adjustment on the novel support assembly 9. The threaded rods 20 permit an infinite adjustment of the stop-motion mechanism 13 longitudinally of the loom within a broad range, by manipulation of the nuts 46 and 47, and the vertical slots 33, and 34 in the mounting plate 35 permit vertical adjustment of the stop-motion mechanism 13, while transverse adjustment of the positioning of the stop-motion mechanism 13 is accomplished through transverse manipulation of the horizontal plate 27 of angle bracket 26 by loosening the bolts which hold the plate 27 on the loom frame 11.
Referring to FIG. 7, it will be observed that each of the spacer blocks 17 is shaped to snugly clamp the electrodes 15 and separator bars 16 when the end member 22 are moved toward each other by manipulation of the nuts 48 and 49 adjacent the innermost and outermost end pieces 22.
Additional support for the medial portion of the electrodes 15 and separator bars 16 is provided by a bridge 50 located at about the mid-point of the electrodes 15 and separator bars 16 between the sides of the loom. The bridge 50 comprises a base plate 51, an intermediate spacer plate 52 and a top spacer plate 53 (FIG. 6). The base plate 51 is shown as being of rectangular configuration while the intermediate spacer plate 52 has notches 54 communicating with its lower edge 55 and spaced and shaped to receive separator bars 16. The notches 54 are dimensioned to tightly receive the separator bars to minimize movement of the bars resulting from the normal vibration of the loom. As best seen in FIG. 6, the lower edge of the separator bars 16 rests on the upper surface 58 of base plate 51. The intermediate separator plate 52 also has a plurality of notches 56 communicating with its upper edge 57 to receive the electrodes 15.
The electrodes 15 may each have a stiffening rib 60 extending longitudinally along one side and the notches 56 are cut to such a depth in the plate 52 that with the electrodes 15 fully seated in their respective notches 56 the ribs 60 on the electrodes substantially coincide with the upper edge 57 of plate 52. The upper stabilizing plate 53 has corresponding notches 61 formed in its lower edge and communicating therewith to receive the upper portions of the electrodes 15 seated in notches 56 in intermediate plate 52. The three plates 51, 52, and 53 are held together by metal straps 62 and 63, the straps 62 and 63 being anchored to the base plate 51 as by bolts 64 and to the top plate 53 as by bolts 65.
The separator blocks 17 and the end blocks 22 are each shaped to define chambers for the reception of the electrodes 15 and separator bars 16. As most clearly seen in FIG. 7, each block 17 has a chamber 70 in its lower portion slightly less than the thickness of the separator bar 16 received in the chamber 70, and a chamber 71 in its upper portion to receive an electrode 15. The chamber 71 includes an arcuate recess 72 to accommodate the rib 60 on electrode 15 and the chamber 71 is slightly less than the thickness of the rib 15 so that the rib protrudes beyond the chamber 71 to bear against a straight wall 73 of the adjoining spacer block 17. In like manner, the separator bars 16 project beyond their respective chamber 70 to bear against a straight wall 74 on the adjacent separator block 17. Note that the outermost end block 22 has a chamber 70 for a separator bar 16 while the innermost end block 22 has a straight wall 74 bearing against the separator bar 16 in the chamber 70 of the adjoining separator block 17.
Arranged in this manner, the electrodes 15 and separator bars 16 are held rigidly in place when the nuts 46 and 47 on the threaded bars 20 are tightened to press the blocks 17 and 22 tightly against the electrodes 15 and separator bars 16. This rigid clamping practically eliminates wear of the electrodes and separator bars which normally occurs due to loom vibration.
The electrodes 15 are electrically connected to a source of electricity and grounded by wires 75 connected to springs 76 which easily and conveniently fit into notches in the ends of the electrodes 15.
There is thus provided an improved support assembly for the electric stop-motion mechanism of a weaving loom, which support assembly includes means for adjusting the mechanism longitudinally, transversely and vertically to achieve the optimum operating position, means for quickly, pivoting the stop-motion mechanism out of the way when desired to perform routine or repair operations on the loom without disturbing the warp yarns in the drop wires, and means for automatically repositioning the stop-motion assembly at its said predetermined optimum operating position without further attention by the operator.
Although specific terms have been used in describing the invention they are used in a descriptive sense only and not for purpose of limitation. | The invention comprises a fully adjustable and pivotal support for a warp stop-motion which may be finely adjusted to its optimum operable position and then pivoted upwardly and out of the way when desired, as while changing the warp beam, and instantly and accurately retured to said optimum operating position by means of a positive stop which positions the warp stop-motion mechanism in said optimum operative position automatically without further attention by the operator except to tighten the few bolts necessary to hold the warp stop-motion mechanism in said optimum operating position. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and hereby claims priority to PCT Application No. PCT/EP2008/066988 filed on Dec. 8, 2008 and DE Application No. 10 2008 003 005.8 filed on Jan. 2, 2008, the contents of which are hereby incorporated by reference.
BACKGROUND
[0002] The invention relates to a system for measuring a change in position of a medical device, such as an endoscopy capsule, and to an appliance which utilizes this measurement in order to influence the position of the medical device.
[0003] Endoscopy capsules are used increasingly in medicine to diagnose or treat the inside of a patient. An endoscopy capsule can contain inter alia medical instruments for instance for biopsy or for introducing medicines into the body and/or image systems such as cameras. Furthermore, a permanent magnet can be integrated in the capsule, which affords the capsule a magnetic dipole moment, so that that it can be maneuvered at will with the aid of a magnetic coil arrangement as described in DE 103 40 925 B3 for instance.
[0004] With examinations inside the body using a medical device such as an endoscopy capsule, the position of the device is generally monitored and if necessary influenced. For instance, with an examination of the stomach, this is half filled with water and the endoscopy capsules floats on the water surface. When recording images of the inside of the stomach, the problem arises that the capsule and with it the camera are moved as a result of the water movement which cannot be avoided, so that only unclear, blurred images can be recorded. In the event that a series of images of a certain region is to be recorded, it is necessary for the capsule to be stationary.
[0005] For position determination purposes, electromagnetic measuring methods mostly use low-frequency magnetic alternating fields, which penetrate the human body in an almost uninfluenced fashion, thereby rendering an absolute position determination possible. A system of this type is described in WO 2005/120345 A2. Nevertheless, known systems on the one hand are disadvantageous in terms of a limited measuring accuracy. On the other hand, as a result of a poor signal-to-noise ratio and the necessary long integration time associated therewith, the temporal resolution is relatively minimal and the measuring value delay is comparatively great. Alternatively, phase difference measurements on high-frequency electromagnetic waves were proposed for the absolute position measurement of medical devices in the inside of the body. Account was not taken here of the fact that the wave propagation through body tissue with a different dielectric constant and conductivity results in a considerable deformation of the spherical wave front in the free space. Nevertheless, to enable an absolute position determination, complex correction methods are needed.
SUMMARY
[0006] One potential object is therefore to specify an apparatus and a method, with which a change in position of a medical device can be detected and can counteract a change of this type.
[0007] The inventors proposals assume that the absolute position of the device is not needed to control the position of a medical device inside the body and for a possible position correction but that only changes in position have to be detected in accordance with their direction and at least roughly in accordance with their size. When determining a deviation of the medical device from a target position or more generally if the medical device implements an unwanted movement, a controller can be used, which counteracts the deviation and/or the movement. It is accordingly sufficient only to implement a relative position determination.
[0008] To this end, the medical device sends high-frequency electromagnetic signals continuously or at intervals, the electromagnetic signals being received by several spatially distributed receiving devices. The temporal behavior of the phase differences between the signals received at the receiving devices and a reference signal is monitored in order to detect a movement of the medical device. The reference signal can originate here from a separate reference signal source or from one of the receiving devices. In the event that one or several of the phase differences of the receiving devices change, it is assumed that the medical device has moved, so that if necessary corresponding countermeasures can be taken to counteract the movement.
[0009] The countermeasures are triggered by a control facility as a function of the detected phase differences. The control facility controls a maneuvering apparatus for influencing the position of the medical device, with it being possible for the maneuvering apparatus to be a magnetic coil arrangement, as described in DE 103 40 925 B3.
[0010] The method is advantageous in that only one relative position measurement is implemented, such that as a result of the high signal-to-noise ratio, a rapid measurement and thus a short reaction time ensue. Deviations in the medical device from a target position are thus rapidly detected and can be correspondingly corrected at short notice before the sum of the position changes becomes too great. Furthermore, contrary to the absolute position measurements, no knowledge is advantageously needed relating to the body tissue located between the medical device and/or the transmit facility and the receiving devices (e.g. dielectric constant, conductivity).
[0011] To enable a more precise and rapid absolute position measurement, it is conceivable for the method and/or apparatus to be combined with other, e.g. low-frequency measuring methods for absolute position measurement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] These and other objects and advantages of the present invention will become more apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:
[0013] FIG. 1 shows a first exemplary embodiment of the proposed apparatus,
[0014] FIG. 2 shows a second exemplary embodiment of the proposed apparatus,
[0015] FIG. 3 shows an arrangement of a plurality of receiving devices and a medical device on a patient,
[0016] FIG. 4 shows an overview of the changes in phase difference occurring during a movement of a medical device according to FIG. 3
[0017] FIG. 5 shows a maneuvering apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
First Exemplary Embodiment
[0019] FIG. 1 shows a first embodiment of an apparatus for controlling a position x,y,z of a medical device 10 in a workspace A. The workspace A can be a cavity in the inside of a patient, like for instance the stomach, while the medical device 10 is preferably an endoscopy capsule. The endoscopy capsule 10 is equipped with a permanent magnet and therefore has a magnetic dipole moment, so that it can be maneuvered magnetically and in a contact-free fashion with the aid of a maneuvering apparatus 80 and/or magnetic coil arrangement, as described for instance in DE 102 40 925 B3 and according to the exemplary illustration shown in FIG. 5 .
[0020] Furthermore, the endoscopy capsule 10 contains a transmit facility. This sends a modulated or non-modulated signal S continuously or at intervals, for instance a high frequency signal S with a frequency of 435 MHz.
[0021] The signal S is received by one or several of four receiving devices 11 - 14 in the first exemplary embodiment. To this end, the receiving devices 11 - 14 are provided with an antenna for receiving an electrical and/or a magnetic field. Furthermore, the receiving devices 11 - 14 each contain a preamplifier for amplifying the received signal. The signals SE 11 -SE 14 received and amplified with the receiving devices 11 - 14 are transmitted to a signal processing facility 20 . The signal processing facility 20 contains several facilities 21 - 24 , with each receive facility 11 - 14 being assigned a facility 21 - 24 . The facilities 21 - 24 each have a first and a second signal input and a signal output, with the received signals SE 11 -SE 14 applied in each instance at the second signal input.
[0022] Furthermore, a reference signal source 60 is provided, which generates a reference signal R. The reference signal source 60 may be a reference oscillator, the frequency of which preferably only deviates marginally from the frequency of the signal S. The reference signal R is applied at each first signal input of the facilities 21 - 24 .
[0023] The facilities 21 - 24 preferably each contain a mixing device 31 - 34 and a phase measurer 41 - 44 , with each mixing device 31 - 34 having a first and a second signal input in each instance. The first and/or second signal inputs of the facilities 21 - 24 correspond to the first and/or second inputs of the mixing devices 31 - 34 . The signal outputs of the phase measurer 41 - 44 correspond to the signal outputs of the facilities 21 - 24 .
[0024] The signals applied at the signal inputs of a mixing device 31 - 34 are mixed with one another in a known manner. The output signals of the mixing device 31 - 34 are each forwarded to a signal input of the phase measurer 41 - 44 . The phase measurer 41 - 44 determines the phase position of the signal applied at its input, with, for instance, the signal initially being amplified such that a rectangular signal almost arises and the zero passage of the rectangular signal is then determined. The output signals of the phase measurer 41 - 44 then correspond in each instance to the phase deviations dφ 11 ,dφ 12 ,dφ 13 ,dφ 14 between the phases of the signals, which are applied at the first and second signal inputs of the facilities 21 - 24 and/or the mixing device 31 - 34 . For instance, the signal R is applied at the first signal input of the facility 21 , while the signal SE 11 received at the receive facility 11 is applied at the second signal input of the facility 21 . The output signal of the facility 21 then corresponds to the deviation dφ 11 =φ(SE 11 )−φ(R) between the phase φ(SE 11 ) of the signal SE 11 and the phase φ(R) of the reference signal R. The same applies to the input and output signals of the facilities 22 - 24 , i.e. the output signals of the facilities 21 - 24 correspond to the phase deviations dφ 11 ,dφ 12 ,dφ 13 ,dφ 14 between the phases φ(SE 11 ), φ(SE 12 ), φ(SE 13 ), φ(SE 14 ) of the signals SE 11 -SE 14 received at the receiving devices 11 - 14 and the phase φ(R) of the reference signal R generated by the reference signal source 60 .
[0025] Since the frequencies of the reference signal source 60 and the transmit facility do not generally exactly agree with the endoscopy capsule 10 , the phase deviations dφ 11 ,dφ 12 ,dφ 13 ,dφ 14 do are not temporally constant but increase linearly with time. Provided that the endoscopy capsule 10 is not moved, the difference between the deviations must however be temporally constant. A difference formation apparatus 50 is therefore provided in the signal processing facility 20 , into which the deviations dφ 11 ,dφ 12 ,dφ 13 ,dφ 14 are fed.
[0026] In the difference formation apparatus 50 , phase differences Δφ 1 , Δφ 2 , Δφ 3 are determined. Here any of the phase deviations dφ 11 ,dφ 12 ,dφ 13 ,dφ 14 is determined as a reference value dφ ref , for instance dφ ref =dφ 11 , and the difference between the remaining phase deviations dφ 12 ,dφ 13 ,dφ 14 and the reference value dφ ref is formed, i.e. Δφ 1 =dφ 12 −dφ 11 , Δφ 2 =dφ 13 −dφ 11 and Δφ 3 =dφ 14 −dφ 11 . The selection of one of the deviations as a reference value dφ ref can take place randomly or for instance as a function of the sum of the deviations dφ 11 ,dφ 12 ,dφ 13 ,dφ 14 .
[0027] The phase differences Δφ 1 , Δφ 2 , Δφ 3 are determined temporally continuously or at intervals.
[0028] The phase differences Δφ 1 , Δφ 2 , Δφ 3 are fed to a control facility 70 . The control facility 70 is connected to a maneuvering apparatus 80 for influencing the position x, y, z of the endoscopy capsule 10 and uses the phase differences Δφ 1 , Δφ 2 , Δφ 3 to control the maneuvering apparatus 80 . Here x, y, z defines the position of the center of gravity of the endoscopy capsule 10 in a Cartesian coordinate system, which can be predetetermined for instance by the geometry of the maneuvering apparatus 80 .
Second Exemplary Embodiment
[0029] In a second, preferred exemplary embodiment, which is shown in FIG. 2 , the medical device 10 , as in the first exemplary embodiment, sends a modulated or non-modulated signal S with the aid of a transmit facility continuously or at intervals. The signal S is received by the receiving devices 11 - 14 , with one of the receiving devices 11 - 14 subsequently being referred to as the first receive facility 14 and the remaining receiving devices being referred to as second receiving devices 11 - 13 . The receiving devices 11 - 14 each include an antenna for receiving an electrical and/or a magnetic field and a preamplifier for amplifying the received signal.
[0030] The signals SE 11 -SE 14 received and amplified with the receiving devices 11 - 14 are transmitted to a signal processing facility 20 . In the signal processing facility 20 , phase differences Δφ 1 , Δφ 2 , Δφ 3 are determined between the signals SE 11 -SE 13 received at the second receiving devices 11 - 13 and the signal SE 14 received at the first receive facility 14 , i.e. Δφ 1 =φ(SE 11 )−φ(SE 14 ) Δφ 2 =φ(SE 12 )−φ(SE 14 ), Δφ 3 =φ(SE 13 )−φ(SE 14 ), with φ(X) symbolizing the phase of a signal X. The received signal SE 14 of the first receive facility 14 is used correspondingly as a reference signal R within the meaning of the first exemplary embodiment.
[0031] Facilities 21 - 23 , for instance phase detectors 21 - 23 , are provided for determining the phase differences Δφ 1 , Δφ 2 , Δφ 3 , with the number of phase detectors 21 - 23 corresponding at least to the number of the second receiving devices 11 - 13 .
[0032] Each phase detector 21 - 23 has a first and a second signal input and a signal output. In this way the first receive facility 14 for transmitting the received signal SE 14 is connected to the first signal input of each phase detector 21 - 23 . The second receiving devices 11 - 13 are each connected to the second signal input of the phase detectors 21 - 23 , while the signal outputs for transmitting the determined phase differences Δφ 1 , Δφ 2 , Δφ 3 are connected to a control facility 70 .
[0033] Since the frequencies of the received signals SE 11 -SE 14 are identical, it is possible to determine the phase differences in the second exemplary embodiment directly, contrary to the first exemplary embodiment.
[0034] The phase differences Δφ 1 , Δφ 2 , Δφ 3 are fed to the control facility 70 as in the first exemplary embodiment. As in the first exemplary embodiment, the control facility 70 is connected to a maneuvering apparatus 80 for influencing the position x, y, z of the endoscopy capsule 10 and uses the phase differences Δφ 1 , Δφ 2 , Δφ 3 to control the maneuvering apparatus 80 .
[0035] The signal processing facility 20 is configured such that instead of the received signal SE 14 of the first receive facility 14 , a signal SE 11 -SE 13 received at any of the other receiving devices 11 - 13 can be used as a reference signal R, i.e. for instance the signal SE 12 of the receive facility 12 . Accordingly, the phase differences Δφ 1 , Δφ 2 , Δφ 3 would be calculated according to Δφ 1 =φ(SE 11 )−φ(SE 12 ) Δφ 2 =φ(SE 13 )−φ(SE 12 ), Δφ 3 =φ(SE 14 )−φ(SE 12 ). The receive facility 12 then assumes the role of the first receive facility, while the receiving devices 11 , 13 , 14 form the group of the second receiving devices. A realization with the aid of a first and a second multiplexer would be conceivable, with the first multiplexer selecting one signal from the signals SE 11 -SE 14 , e.g. SE 14 and outputting this to the first signal inputs of the phase detectors 21 - 23 , while the second multiplexer selects the remaining three signals from the signals SE 11 -SE 14 , in the example SE 11 , SE 12 and SE 13 and forwards these to the second signal inputs in each case. Alternatively, other possibilities of defining any of the receiving devices 11 - 14 in a circuit-specific fashion as a first receive facility and conveying the signals SE 11 -SE 14 accordingly to the first and second signal inputs of the phase detectors are also conceivable.
[0036] More than four receiving devices are advantageously used to increase the measuring accuracy. FIG. 3 shows a system comprising an endoscopy capsule 10 and eight receiving devices 11 - 18 , which are attached in the region of a workspace A. In a concrete application, the workspace A can be the inside of a patient, with it being possible for the endoscopy capsule to be located in the stomach of the patient for instance. In addition to the receiving devices 11 - 18 shown in FIG. 3 , further receiving devices can be provided in planes in front of and behind the image plane shown. The receiving devices are advantageously arranged such that the whole region to be examined with the endoscopy capsule 10 is surrounded by a network of receiving devices.
Functionality
[0037] The first and second exemplary embodiment differ in terms of providing the reference signal R. While a separate reference signal source 60 provides the reference signal R in the first exemplary embodiment, any of the receiving devices 11 - 14 in the second exemplary embodiment is used as a source of the reference signal R. The basic methods performed in the control facility 70 for controlling the position x,y,z of the endoscopy capsule 10 based on the determined phase differences Δφ 1 , Δφ 2 , Δφ 3 are identical for both exemplary embodiments.
[0038] With the system shown in FIG. 3 , seven phase differences Δφ 1 to Δφ 7 are determined and fed to the control facility 70 . In the event that the endoscopy capsule 10 is not moved, i.e. is stationary relative to the receiving devices 11 - 18 , the phase differences Δφ 1 to Δφ 7 are temporally constant.
[0039] If the capsule 10 is moved, at least some of the phase differences Δφ 1 to Δφ 7 change during the movement. It can generally be assumed here that a large change in a phase difference accompanies a large movement of the capsule 10 in the direction of the connecting line between the capsule 10 and that of the corresponding receive facility.
[0040] The control facility 70 evaluates the determined phase differences Δφ 1 to Δφ 7 by the temporal behavior Δφ 1 (t) to Δφ 7 (t) of the phase differences Δφ 1 to Δφ 7 fed thereto being monitored. The momentary, i.e. phase differences Δφ 1 (t 2 ) to Δφ 7 (t 2 ) determined at a time instant t 2 , are compared here with the phase differences Δφ 1 (t 1 ) to Δφ 7 (t 1 ) determined immediately beforehand at a time instant t 1 (t 1 <t 2 ).
[0041] Alternatively, the current phase differences Δφ 1 (t 1 ) to Δφ 7 (t 1 ) can be stored as reference values at a first arbitrary time instant t 1 . For instance, if an operator of the system has moved the endoscopy capsule 10 into a target position x(t 1 ), y(t 1 ), z(t 1 ), in which a series of images of a certain region of the inside of the stomach is to be recorded, it is necessary for the capsule 10 to be stationary. At this time instant t 1 , the current phase differences Δφ 1 (t 1 ) to Δφ 7 (t 1 ) determined are stored by the operator pushing a button for instance. The subsequent phase differences Δφ 1 (t) to Δφ 7 (t) determined at second time instants t are continuously compared in the control facility 70 with the stored reference values Δφ 1 (t 1 ) to Δφ 7 (t 1 ).
[0042] With a change in one or several of the phase differences Δφ 1 to Δφ, a control of the maneuvering apparatus 80 is initiated by the control facility 70 . In the two exemplary embodiments, the maneuvering apparatus 80 is preferably an arrangement with several individual coils for the contactless guidance of the endoscopy capsule 10 , as is described for instance as a “magnetic coil arrangement” in DE 103 40 925 B3. The maneuvering apparatus 80 generates, by a correspondingly targeted current feed of the individual coils, one or several magnetic field components, B x , B y , B x and/or one or several gradient fields G i,j =∂B i /∂j with i,j=x, y, z, as a result of which the interaction with the magnetic dipole moment of the permanent magnet of the capsule 10 can exert torques and/or forces on the capsule 10 . The targeted current feed of the individual coils and consequently thereof the gradient fields G i,j and/or the magnetic field components B x , B y , B z are developed as a function of the control predetermined by the control facility 70 .
[0043] The control takes place in this way in that with a change in the position x, y, z of the endoscopy capsule 10 , which is connected to a change in one or several phase differences as described above, the gradient fields G i,j and/or the magnetic field components B x , B y , B z are adjusted so that the generated forces and torques counteract the detected movement of the capsule.
[0044] As the relationships between the current feed of one or several of the individual coils and the torques and forces thus generatable are known in respect of amount and direction, the movement of the endoscopy capsule which is detected by monitoring the phase differences can be selectively counteracted by the corresponding individual coils having current applied in accordance with the detected movement direction and if necessary amplitude. Reference is made to DE 103 40 925 B3 for the basic functionality of the maneuvering apparatus 80 . The maneuvering apparatus 80 of the apparatus operates comparably, but is not defined in terms of design of the “magnetic coil arrangement” in DE 103 40 925 B3 but can instead also include more or fewer individual coils and be embodied in order to generate another number of magnetic degrees of freedom than the maneuvering apparatus or “magnetic coil arrangement” in DE 103 40 925 B3.
[0045] The result of the control of the maneuvering apparatus 80 by the control facility 70 is correspondingly such that the phase differences Δφ 1 (t) to Δφ 7 (t) remain temporally constant or the currently determined phase differences Δφ 1 (t) to Δφ 7 (t) correspond to the stored reference values Δφ 1 (t 1 ) to Δφ 7 (t 1 ). Unwanted movements of the endoscopy capsule or deviations in the position x, y, z of the capsule 10 from a target position x(t 1 ), y(t 1 ), z (t 1 ) can be counteracted.
Further Embodiments
[0046] The movement of the capsule 10 in the x-direction, which is indicated by the arrow in FIG. 3 , is reflected in a comparatively large change in the phase differences Δφ 2 , Δφ 6 determined in respect of the receiving devices 12 , 16 . The phase differences Δφ 4 , Δφ 6 determined in respect of the receiving devices 14 , 18 are by contrast not changed or only changed minimally. FIG. 4 shows a diagram, in which, for the receiving devices 11 - 18 , the changes in the phase differences Δφ 1 , Δφ 7 , are plotted in any units, which can result during a movement of the capsule 10 in the x-direction according to FIG. 3 .
[0047] During the evaluation of the phase differences in the control facility 70 , only a limited number of phase differences, in particular only the largest phase differences Δφ 1 , Δφ 2 , Δφ 3 , Δφ 5 , Δφ 6 , Δφ 7 are preferably taken into account, while the remaining Δφ 4 is disregarded. A weighting can alternatively take place in accordance with the sums of the phase differences.
[0048] In the event that the endoscopy capsule is equipped with an imaging system such as a camera and transmits a video signal, the transmitter available for this purpose in the capsule can also be used to transmit the signal S, with a carrier frequency of 433 MHz typically being used. It is then possible to dispense with a separate transmit facility or other additional equipment in the capsule for transmitting the signal S for position control purposes. The transmit program of the capsule must possibly be changed such that the image transmission is interrupted at predetermined intervals and a non-modulated signal is sent for the position measurement for a few microsecs.
[0049] The receiving devices can be attached directly to the patient, for instance by adhesion to the skin, or on the maneuvering apparatus 80 . For practical reasons, the receiving devices inside the cylindrical maneuvering apparatus 80 are attached to the inner cylinder wall in the case of a maneuvering apparatus 80 and/or magnetic coil arrangement as described in DE 103 40 925 B3 for instance.
[0050] The invention has been described in detail with particular reference to preferred embodiments thereof and examples, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention covered by the claims which may include the phrase “at least one of A, B and C” as an alternative expression that means one or more of A, B and C may be used, contrary to the holding in Superguide v. DIRECTV, 69 USPQ2d 1865 (Fed. Cir. 2004). | A system measures a change in position of a medical appliance, such as an endoscopy capsule. A device uses this measurement in order to influence the position of the medical appliance. The medical appliance sends a signal that is received by a multiplicity of spatially separate receiving devices. The time profile of the phase differences between the received signals and a reference signal provides an indication of whether the medical appliance has moved. In the event of a movement being detected, a maneuvering device can be regulated by a regulating means in such a way that the maneuvering device generates forces and/or torques and applies them to the medical appliance to counteract the detected movement. | 0 |
TECHNICAL FIELD
[0001] The present disclosure relates to sealing arrangements in gas turbines, and particularly to sealing arrangements comprising two seals to seal the gap between the first vane and the picture frame.
BACKGROUND OF THE INVENTION
[0002] In a gas turbine, there is a gap between the picture frames in the combustor outlet and the first vane of the turbine. Movement of the two parts relative to one another can be considerable, and a gap must be left between the parts to avoid contact. The gap is generally purged with cooling air. It has been appreciated that it would be advantageous to improve the design around this gap to, for example, reduce the cooling air requirements.
SUMMARY OF THE INVENTION
[0003] The invention is defined in the appended independent claims to which reference should now be made. Advantageous features of the invention are set forth in the dependent claims.
[0004] According to a first aspect of the invention, there is provided a gas turbine comprising a picture frame, a first vane, and a sealing arrangement to seal a gap between the picture frame and the first vane, the sealing arrangement comprising two seals arranged in series between the picture frame and the first vane. This can help to reduce leakage and hot gas ingestion in the gap between the picture frame and the first vane, particularly on the inner platform (inner diameter) between each picture frame and the first vane (rocking vane). In particular, this can seal the gap during all operating conditions despite first vane movements in both the axial and radial directions (compared to the gas turbine longitudinal axis). The noble parts (first vane and picture frame) of the gas turbine are not affected, and the solution can be retrofitted to existing turbines. Use of two seals can also provide redundancy, so that the gap can still be sealed if one of the seals fails or the performance of one or both the seals deteriorates. The seal closest to the hot gas flow can reduce hot gas ingestion in particular, and the seal furthest from the hot gas flow can reduce and/or control the flow of cooling fluid in particular.
[0005] In one embodiment, one of the seals is a honeycomb seal, a dogbone seal, a hula seal or a piston seal and the other seal is a honeycomb seal, a dogbone seal, a hula seal or a piston seal. A piston seal can compensate for both axial and radial displacement, as the piston can be pushed up against the first vane by pressure behind the piston seal in the piston volume. In one embodiment, one of the seals is a honeycomb seal, the first vane comprises a sealing portion arranged to seal the gap in combination with the honeycomb seal.
[0006] In one embodiment, at least one of the seals is a hula seal, and at least one of the at least one hula seals is a conical hula seal. A conical hula seal can be particularly suited to cope with vane movements in both the axial and radial directions (compared to the gas turbine longitudinal axis).
[0007] In one embodiment, the conical hula seal comprises an inner part, a plurality of fingers and an outer part, wherein the inner part is attached to one end of each of the plurality of fingers and the outer part is attached to the other end of each of the plurality of fingers.
[0008] In one embodiment, at least one of the seals is a dogbone seal, and the picture frame comprises a socket for holding the dogbone seal. In one embodiment, at least one of the seals is a piston seal, the piston seal comprises a piston seal front end for contacting a first vane, the majority of the piston seal front end is at least half the width of the widest part of the piston seal in a radial direction relative to a gas turbine longitudinal axis, and the piston seal front end has a tapered portion for contacting the first vane.
[0009] In one embodiment, the first vane comprises a first vane contact surface to contact at least one of the seals. In one embodiment, the first vane contact surface is parallel or substantially parallel to a surface of the picture frame on the opposite side of the gap.
[0010] In one embodiment, the first vane contact surface is conical or spherical. This can help better seal the gap. In one embodiment, the first vane contact surface is angled such that an elastic range of movement of the first vane relative to the picture frame is minimised. This can minimise the gap width and make sealing the gap easier.
[0011] According to a second aspect of the invention, there is provided a method of cooling a gas turbine comprising a picture frame, a first vane, and a sealing arrangement to seal the gap between the picture frame and the first vane, the sealing arrangement comprising two seals arranged in series between the picture frame and the first vane, comprising the step of supplying cooling fluid to the gap between the picture frame and the first vane. This can purge the gap to reduce hot gas ingestion.
[0012] In one embodiment, the method comprises the step of maintaining a higher pressure at the end of the gap furthest from a hot gas flow than the pressure at a hot gas flow end of the gap.
[0013] In one embodiment, at least one of the seals is a piston seal and the method comprises the step of supplying cooling fluid to a volume between the piston seal and the picture frame such that the piston seal remains in contact with the first vane.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawings in which:
[0015] FIG. 1 shows a cross-section of an embodiment of the invention comprising a honeycomb seal and a conical hula seal;
[0016] FIG. 2 shows a cross-section of an embodiment of the invention comprising a honeycomb seal and a dogbone seal;
[0017] FIG. 3 shows a cross-section of an embodiment of the invention comprising two honeycomb seals;
[0018] FIG. 4 shows a perspective view of a conical hula seal on a bulkhead;
[0019] FIG. 5 shows a top view of the conical hula seal of FIG. 4 ;
[0020] FIG. 6 shows graphically the movement of a point on the first vane surface during gas turbine operation;
[0021] FIG. 7 shows a cross-section view of a piston seal; and
[0022] FIG. 8 shows a cross-section view of an alternative piston seal.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] FIG. 1 shows a first vane 1 (rocking vane) on one side of a gap 24 , 26 , 44 , 46 , to be sealed, with a first sealing portion 2 and a second sealing portion 7 (vane tooth). On the other side of the gap 24 , 26 , 44 , 46 to be sealed is a picture frame 4 and a bulkhead 5 attached to the picture frame 4 . The bulkhead 5 is shown as a separate component to the picture frame 4 in the embodiments in this application, but the bulkhead 5 may also be an integral part of the picture frame 4 . In the gap 24 , 26 , 44 , 46 between the first vane 1 and the picture frame 4 and bulkhead 5 , a first seal (honeycomb seal 3 ) and a second seal (conical hula seal 6 ) are arranged.
[0024] The honeycomb seal 3 is arranged between the picture frame 4 and the bulkhead 5 on one side of the gap 44 , 46 . The first sealing portion 2 , which is a protrusion extending from the first vane 1 , extends across the gap 44 , 46 to interact with the honeycomb seal 3 and seal the gap 44 , 46 .
[0025] The conical hula seal 6 extends between the second sealing portion 7 and the bulkhead 5 . Preferably, the surface 12 of the bulkhead adjacent to the conical hula seal 6 and the surface 14 of the second sealing portion 7 adjacent to the conical hula seal 6 are parallel or substantially parallel (in use they will not always be parallel), both extending in a hula seal direction 16 , the hula seal direction 16 being at an angle from the longitudinal axis direction 18 . The longitudinal axis direction 18 is the direction of the longitudinal axis of the gas turbine (not shown), which is generally also parallel to the axis of the first vane 1 and the picture frame 4 .
[0026] In FIG. 2 , an alternative embodiment is shown in which a dogbone seal 8 is provided as the second seal rather than a conical hula seal. The dogbone seal 8 comprises a bulkhead portion 54 adjacent to the bulkhead, a first vane portion 56 adjacent to the second sealing portion 7 , and a central portion 58 joining the bulkhead portion and the first vane portion. The bulkhead portion 54 and the first vane portion 56 are typically cylindrical. The bulkhead 5 also differs from the bulkhead in FIG. 1 in that a socket 20 is provided to hold the dogbone seal 8 . In FIG. 2 , the last part of the gap 24 is effectively part of the compressor plenum.
[0027] In FIG. 3 , an alternative embodiment is shown in which a second honeycomb seal 9 is provided as the second seal. The bulkhead 5 comprises a recess 30 in which the second honeycomb seal 9 is placed. In addition, the second sealing portion 7 comprises a second sealing portion nose 10 . This second sealing portion nose 10 has the same function as first sealing portion 2 . The first seal (honeycomb seal 3 ), as in the embodiments in FIGS. 1 and 2 , is provided to seal a first gap 44 , 46 which extends in a direction 34 perpendicular to the longitudinal axis direction 18 . The second seal (second honeycomb seal 9 ) is provided to seal a second gap 24 , 26 which extends in a direction 38 , the direction 38 being at an angle A from the longitudinal direction 18 .
[0028] Hula seals such as that shown in FIG. 1 will now be described in more detail. In annular hula seals, the hula seal describes a ring in which the inner part and the outer part are at the same distance from the central axis of the hula seal (i.e. the axis through the centre of the hula seal, which is the hula seal longitudinal axis in the longitudinal axis direction 18 ). In contrast, a conical hula seal has an inner part that is closer to the central axis of the hula seal than the outer part. In other words, the hula seal direction in an annular hula seal is parallel to the longitudinal axis direction 18 (hula seal longitudinal axis), whereas the hula seal direction in a conical hula seal is at an angle from the longitudinal axis direction 18 .
[0029] A cone is a three-dimensional geometric shape that tapers smoothly from a flat base; the base may be circular or may be another shape. Mathematically, a conical hula seal is conical frustum, being in the shape of the surface of the frustum of a cone (i.e. a section of the cone not including the apex, also known as a truncated cone), in contrast to an annular hula seal in which the hula seal follows the shape of the surface of a cylinder. It should be noted for completeness that hula seals do not strictly describe a precisely annular or conical shape, as can be seen in FIG. 3 for example, where a conical hula seal 6 follows a hula seal direction 16 but the curvature of the fingers deviates slightly from a perfect cone.
[0030] FIGS. 4 and 5 show a conical hula seal 6 attached to a bulkhead 5 , which is in turn attached to or part of a picture frame 4 (see FIG. 1 ). The conical hula seal 6 comprises an inner part 64 extending in a circumferential direction 69 relative to a longitudinal axis direction 18 (hula seal axis direction, see FIG. 1 ). The inner part 64 is configured to be attached to the surface 12 (see FIG. 1 ) of the bulkhead 5 . A plurality of fingers 66 , each attached to the inner part 64 , extend away from the inner part 64 in a hula seal direction 16 (see FIG. 1 ). An outer part 68 is provided at the distal end of the fingers 66 from the inner part 64 . The conical hula seal extends in a hula seal direction 16 (see FIG. 1 ) at an angle A from the longitudinal axis direction 18 . A cross section of the conical hula seal 5 along the line I-I in FIG. 5 would correspond to the view of the conical hula seal 5 in FIG. 1 . It is noted that the bulkhead of FIG. 4 is a different design to the bulkhead of FIG. 1 .
[0031] The fingers 66 do not extend in a straight line, but curve such that the direction of each finger describes an angle greater than angle A (see FIG. 1 ) nearer the inner part 64 and an angle smaller than angle A near the outer part 68 . The outer part 68 is arranged to slidably contact the surface 12 (see FIG. 1 ) of the bulkhead 56 .
[0032] The hula seal may be an entire ring or may be made up of multiple individual hula seals (hula seal segments). The hula seal of FIG. 5 is a hula seal segment. In one example, 20 hula seals are placed around the 360° annular joint, each extending 15° around the circumference in the circumferential direction 40 . The other types of seals described herein may also be segmented in this way.
[0033] In a gas turbine, a plurality of picture frames (sequential liner outlets) are arranged around the longitudinal axis of the gas turbine in a ring, with the picture frames typically being attached to sequential liners and with the sequential liners surrounding can combustors. In other words, the picture frames all intersect a plane perpendicular to the longitudinal axis. The sealing solution discussed in this application can be applied on the inner diameter of the picture frames (the edge of the picture frames closest to the longitudinal axis). Preferably, each picture frame has a separate seal segment or segments; that is, seal segments do not extend across multiple picture frames in the circumferential direction relative to the longitudinal axis. This can allow for single vane/blade assembly and/or disassembly during manufacture, maintenance and repair.
[0034] The sealing solution discussed in this application is preferably for sealing a gap between two static parts such as the gap between the picture frame and the first vane.
[0035] When in use, the second sealing portion surface 14 (more specifically, a particular spot on the second sealing portion surface 14 ) will move along a path similar to that shown in FIG. 6 during its operation cycle. The range of movement fits within an angled rectangular box 148 , angled at an angle α from the longitudinal axis direction 18 . Preferably, angle A (see FIGS. 1 and 3 ) is the same or substantially the same as angle α. There are two directions of movement, the sliding range 158 and the elastic range 159 . Movement in the direction of the sliding range 158 can be due to rocking (rotation) of the first vane, for example, and movement in the direction of the elastic range 159 can be due to thermal expansion/contraction of components, for example.
[0036] Initially, at the assembly or cold position 150 in FIG. 6 , the first vane 1 is in a certain position. During startup, the first vane starts moving in a direction as shown by movement line 156 , passing through point 151 which may be a first maximum extent in the sliding range. At full load, the first vane position may be at point 152 , and during steady state operation the first vane position may be at point 153 . During operation, the loading may vary, and the first vane position may vary accordingly, moving on or near the movement line 156 in the area between and around points 152 and 153 . On shut down, the first vane then cools and continues further around the movement line 156 . During shut down, the first vane reaches a second maximum extent on the sliding range at point 154 . Once fully cooled, the first vane will have completed a full circle of movement line 156 , arriving back at its cold position at point 150 . The movement line 156 of FIG. 6 and the description of the points on the curve are an approximation, and deviations may occur from this approximation.
[0037] During assembly of the gas turbine, the sealing portion 2 is crushed into the honeycomb seal 3 and generally stays in contact during operation. Similarly, the second sealing portion nose 10 would be crushed into the honeycomb seal 9 .
[0038] In use, cooling fluid may be supplied to the gap between the picture frame and the first vane. This can help reduce hot gas ingestion and can purge the gap.
[0039] A further alternative seal is shown in FIG. 7 , namely a piston seal 15 . As with the other seals described herein, the piston seal 15 is designed to seal the gap 24 , 26 between the second sealing portion 7 of the first vane 1 and the bulkhead 5 , which is attached to the picture frame 4 . At a front end of the piston seal, a piston seal front end 107 is arranged to contact the second sealing portion surface 14 ; the front end of the piston seal is shaped like one half of a dogbone seal. A back end 105 of the piston seal 15 is arranged in a piston volume 102 of the bulkhead 5 . The piston seal 15 can move relative to the bulkhead 5 . At a back end 104 of the piston volume 102 , a source of pressure (not shown) such as a source of cooling fluid is provided. Optionally, a notch 108 for an additional seal (not shown; for example a rope seal) is provided in one or both of the side walls of the piston. This notch could alternatively be in one of both of the side walls of the piston volume. This additional seal can help reduce leakage past the back end 105 of the piston seal 15 .
[0040] FIG. 8 shows an alternative embodiment of the piston seal of FIG. 7 , with an alternative shape of piston seal front end 107 . In this design, a majority of the extent (preferably at least 75%) of the piston seal front end (i.e. the part of the piston seal extending across the gap to contact the first vane) is more than half the width of the piston volume (the width of the piston volume in the direction perpendicular to the longitudinal axis direction 18 ; this is normally the same or very similar to the width of the main part of the piston seal). This design may be more rigid than the embodiment in FIG. 7 . The part of the front end 107 adjacent to the first vane is preferably tapered. The taper is preferably a convex shape; this can allow better contact with the first vane over a range of operating conditions.
[0041] The piston seal 15 may be various shapes besides the examples in FIGS. 7 and 8 .
[0042] As with many of the other embodiments described herein, the second sealing portion surface 14 in FIG. 6 is preferably substantially parallel to the bulkhead surface, on the opposite side of the gap.
[0043] The piston seal embodiment in FIGS. 7 and 8 is shown with a piston volume 102 in the bulkhead 5 parallel to longitudinal axis direction 18 , but the piston volume 102 may be angled in other directions, for example perpendicular to the second sealing portion surface 14 . The piston seal would also be re-orientated accordingly in line with the piston volume.
[0044] The depth of the piston volume 102 from the bulkhead surface 12 to the back end 104 of the piston volume 102 may be determined during a design phase based on the length of the piston seal 15 and the expected size of the gap between the bulkhead surface 12 and the second sealing portion surface 14 .
[0045] When in use, the pressure in the cavity in between the back end 104 of the cavity 102 and the back end 105 of the piston seal 15 is preferably higher than the pressure in the gap 24 , 26 on either side of the piston seal 15 . At a minimum, the pressure at the back end 105 should be high enough to keep the piston seal front end 107 adjacent to the second sealing portion surface 14 . The honeycomb seal 3 and/or the second honeycomb seal 9 may also have a similar pressure profile, with a source of pressure such as a source of cooling air provided to push the honeycomb seal 3 /second honeycomb seal 9 against the first sealing portion and second sealing portion nose respectively.
[0046] A limited number of specific embodiments are described above. More generally, various sealing solutions can be used to seal the gap between the picture frame 4 and the first vane 1 . For the first seal, a honeycomb seal is shown in FIGS. 1 to 3 , but any of the other seals described in this application could also be used as the first seal. Similarly, any of the seals in this application could be used as the second seal. Any combination of seals is also possible. For example, both the first and second seals could be conical hula seals, with the picture frame and first vane designed so that the picture frame and first vane have the structure shown surrounding the conical hula seal in FIG. 3 for both the first seal and the second seal. Three or more seals in series could also be provided.
[0047] The first and second seals would be in series; that is, the second seal would be in a different part of the gap to the first seal in the axial direction perpendicular to the longitudinal axis direction 30 . In other words, any escaping hot gas from the hot gas flow would have to pass through both the conical hula seal and the second seal.
[0048] The seals described herein may be an entire ring or may be made up of multiple individual seals (seal segments). For example, the conical hula seal 6 of FIG. 4 is a hula seal segment. In one example, 20 seals are placed around the 360° annular joint, each extending 15° around the circumference in the circumferential direction 69 .
[0049] Each seal can describe a partial or full ring as described above. The longitudinal axis direction 18 will typically be perpendicular to the plane of this partial or full ring. For seal segments, the longitudinal axis of each seal segment is the longitudinal axis of a full ring of seal segments. The seal longitudinal axis will generally also be the longitudinal axis of the picture frame at the end of the sequential liner (the combustor outlet) and/or the gas turbine longitudinal axis.
[0050] The first sealing portion 2 and the additional seal portion 10 may be various shapes; these parts are required to extend across the gap from the first vane to interact with a honeycomb seal. Similarly, the socket 20 could vary in shape depending on the shape of the dogbone seal and the recess 30 could vary depending on the shape of the second honeycomb seal and the bulkhead.
[0051] The bulkhead 5 is shown varying in shape in the different embodiments shown in the Figures to accommodate the different types of seal. These bulkhead shapes are examples, and other bulkhead shapes are also possible. For example, a bulkhead of the shape shown in FIG. 1 could be amended by the addition of a socket 20 for the dogbone seal but otherwise retain its shape. The bulkhead surface, second sealing portion surface and first vane shape can also vary depending on the seals used.
[0052] The vane tooth 7 is a part of the first vane 1 in the embodiments above, but may also be a separate component attached to the first vane. The first sealing portion 2 and the additional seal portion 10 may also each be either an integral part of the first vane 1 or separate components attached to the first vane.
[0053] The honeycomb seal 3 as a first seal is shown between the picture frame and the bulkhead in the embodiments described above. Alternatively, the honeycomb seal 3 could be attached only adjacent to the picture frame or only adjacent to the bulkhead.
[0054] In FIG. 3 , the honeycomb seal 9 as a second seal is angled at an angle A from the longitudinal axis direction 18 . Alternatively, a second honeycomb seal at a different angle could be used, for example a honeycomb seal similar to the honeycomb seal as a first seal in FIGS. 1 to 3 or a honeycomb seal at an angle parallel to the longitudinal axis direction. The design of the bulkhead 5 and the second sealing portion 7 would need adjusting accordingly. Similarly, the honeycomb seal 3 as a first seal of any of the embodiments could be angled in a different direction to that shown in FIGS. 1 to 3 .
[0055] The honeycomb is generally orientated so that it can elastically deform under the pressure of the first sealing portion 2 or the second sealing portion surface 14 . The lines shown in the honeycomb seal 3 and second honeycomb seal 9 show the walls of the honeycomb; that is, the hexagonal nature of the honeycomb structure would be seen if the seal was viewed in the direction of the lines shown in the honeycomb. The honeycomb seal 3 shown in the Figures is aligned such that the hexagonal honeycomb structure extends in a circumferential direction relative to the gas turbine longitudinal axis. The second honeycomb seal 9 shown in FIG. 9 has the hexagonal honeycomb structure at a different angle, extending perpendicular to the second sealing portion surface 14 .
[0056] Although only a conical hula seal is shown in the Figures, an annular hula seal may also be used. A radial hula seal could also be used, which is the extreme case where the hula seal direction is perpendicular to the longitudinal axis direction 18 . In the case of a conical hula seal, the hula seal direction 16 can be at an angle A other than that shown in the examples, and is preferably set such that angle A is within 15° of angle α, more preferably within 5°, and most preferably at an angle A=α. This is the angle that minimises the relative movement of the first vane and the picture frame/bulkhead during gas turbine operation. This minimises the elastic range 159 and thus enables the gap between the first vane and the picture frame/bulkhead, specifically between the second sealing portion surface 14 and the bulkhead surface 12 , to be minimised. This minimises the required range of movement of the conical hula seal. Similarly, the bulkhead surface 12 associated with the conical hula seal is preferably at an angle within 15° of angle α, more preferably within 5°, and most preferably at an angle A=α, and the second sealing portion surface is preferably within 15° of angle α, more preferably within 5°, and most preferably at an angle A=α.
[0057] The dogbone seal 8 is shown as extending parallel to the longitudinal axis direction 18 in FIG. 2 , but may also extend at an angle to the longitudinal axis direction 18 . Other shapes of dogbone seal could be used besides the example described above; the same is true for the hula seals, dogbone seals, piston seals and honeycomb seals described herein.
[0058] In the embodiment of FIG. 2 , a further socket (not shown) may be provided in the second sealing portion 7 to hold the dogbone seal 8 in place. When the dogbone seal is held at both ends in this way, it will generally need to be made of an extendable material, as the distance between the two sockets will vary when in use. When the dogbone seal is held at only one end, it is generally necessary for the gap to be narrower on the side of the dogbone seal that is at a lower pressure. The further socket (not shown) is optional because the pressure difference can hold the seal in place—the volume 24 (of the gap between the picture frame 4 /bulkhead 5 and the first vane 1 ) that is closer to the longitudinal axis than the dogbone seal 8 is at a higher pressure than the volume 26 (of the gap between the picture frame 4 /bulkhead 5 and the first vane 1 ) further from the longitudinal axis than the dogbone seal 8 . The pressure difference, along with the shape of the gap, which is narrower on the side of the dogbone seal that is at a lower pressure, keeps the dogbone seal in a position that seals the gap. As a result, it is not essential to provide support on the second sealing portion 7 . Alternatively, a socket could be provided in only the first vane 1 (for example in the vane tooth 7 ) and not in the bulkhead 5 .
[0059] Considerable variation is possible in the shape, direction, width and length of the gap between the picture frame and the first vane. The first gap 44 , 46 largely extends in a direction perpendicular to the longitudinal direction 18 , with the first sealing portion 2 extending into the gap to help seal the gap along with honeycomb seal 3 . As implied above when discussing the angles of the various seals, this gap may extend in a different direction in alternative embodiments. Similarly, second gap 24 , 26 may extend in a direction other than that shown in FIGS. 1 to 3 . The shape of the various parts of the first vane (first sealing portion, second sealing portion, second sealing portion nose, second sealing portion surface) may also vary accordingly.
[0060] As with the gap sealed by a dogbone seal 8 in the embodiment in FIG. 2 , the gaps may also vary in width along their extent.
[0061] For ease of reference, different parts of the gap between the first vane and the picture frame/bulkhead have been denoted with reference numerals. The gap comprises three parts, a first gap 44 , 46 , an intermediate region 48 and a second gap 24 , 26 . Dotted lines are shown to delineate where these three regions of the gap could start and finish. The first gap 44 , 46 between the first vane and the picture frame/bulkhead corresponds to the part of the gap with the first seal, and is divided into a volume 44 adjacent to the hot gas flow (not shown) and a volume 46 on the other side of the first sealing portion 2 to the hot gas flow.
[0062] The pressure is typically higher in the volume 46 on the other side of the first sealing portion 2 to the hot gas flow than in the volume 44 adjacent to the hot gas flow; this can allow for a purging flow to leak through the seal, avoiding hot gas ingestion past the first sealing portion and the first seal.
[0063] There is then an intermediate region 48 of the gap between the first gap 44 , 46 and the second gap 24 , 26 , although this intermediate region 48 is optional and the first gap 44 , 46 and second gap 24 , 26 may lead directly to one another.
[0064] The second gap 24 , 26 has a similar structure to the first gap 44 , 46 , with a volume 24 in the gap on the far side of the second sealing portion nose 10 relative to the hot gas flow and a volume 26 in the gap on the near side of the second sealing portion nose 10 relative to the hot gas flow (adjacent to the intermediate region 48 or the first gap 44 , 46 ).
[0065] In the case of a piston, dogbone or hula seal, the seal itself would split the first or second gap region rather than the first sealing portion or the second sealing portion nose as shown in the honeycomb seals embodiment of FIG. 3 . In the case of a hula seal, an additional portion of the volume of the gap is between the hula seal itself and the bulkhead.
[0066] Various modifications to the embodiments described are possible and will occur to those skilled in the art without departing from the invention which is defined by the following claims.
[0000]
REFERENCE SIGNS
1
first vane
2
first sealing portion
3
honeycomb seal
4
picture frame
5
bulkhead
6
conical hula seal
7
second sealing portion
8
dogbone seal
9
second honeycomb seal
10
second sealing portion nose
12
bulkhead surface
14
second sealing portion surface (first vane contact surface)
15
piston seal
16
hula seal direction
18
longitudinal axis direction
20
socket
24
(partial) volume of the second gap (end of
the gap furthest from the hot gas flow)
26
(partial) volume of the second gap
30
recess
34
first gap direction
38
second gap direction
44
(partial) volume of the first gap (hot gas flow end of the gap)
46
(partial) volume of the first gap
48
intermediate region of the gap
54
dogbone seal bulkhead portion
56
dogbone seal first vane portion
58
dogbone seal central portion
64
inner part
66
finger
68
outer part
69
circumferential direction
102
piston volume
104
back end of the piston volume
105
back end of the piston seal
107
piston seal front end
108
notch
148
angled rectangular box
150
assembly/cold position
151
startup
152
full load
153
steady state operation
154
extreme point in shut down
156
movement line
158
sliding range
159
elastic range
A
angle
α
angle | The invention concerns a gas turbine having a picture frame, a first vane, and a sealing arrangement to seal a gap between the picture frame and the first vane, the sealing arrangement including two seals arranged in series between the picture frame and the first vane. In exemplary embodiments, one of the seals is a honeycomb seal, a dogbone seal, a hula seal or a piston seal and the other seal is a honeycomb seal, a dogbone seal, a hula seal or a piston seal. A method of supplying cooling fluid to the gap between the picture frame and the first vane is also disclosed. | 5 |
FIELD OF THE INVENTION
[0001] The present disclosure relates to queue-management techniques and can be applied, for example, to managing first-in/first-out (FIFO) queues in the field of so-called systems-on-chip (SoCs). The disclosure has been developed with attention paid to its possible use in situations in which it is desirable to know in advance the contents of a queue, such as a FIFO queue (i.e. a “look-ahead” function).
BACKGROUND OF THE INVENTION
[0002] System-on-chip technology today facilitates provision of even rather complex systems for communication between different modules of an integrated circuit (for example, a processing unit, memories, peripherals, and other dedicated units) so as to ensure observance of the specifications of performance of the system.
[0003] Various applications foresee the use of first-in/first-out (FIFO) queues between devices with different clock frequencies. For example, a FIFO queue can be set between a first device, for example a microprocessor, which writes information in the FIFO queue and a second device, for example a peripheral or a second microprocessor, which reads the information from the FIFO queue. Each device reads and writes data in the FIFO queue with a rate equal to that of its own clock. However, FIFO queues can be used also in synchronous systems.
[0004] In complex digital systems, the possibility of carrying out a sort of “anticipation” by investigating the subsequent contents of a queue, an operation that is also known by the term “look-ahead”, can be particularly useful for anticipating execution of some processes or tasks and for implementing specific system functions. Currently, specific known approaches to address this problem are not available.
[0005] The inventors have noted that, in principle, an approach represented in FIG. 1 could be envisaged, in which, for search of a value, all the data stored in the FIFO queue are checked. In the communication between a master node 10 and a slave node 20 control information is exchanged on control lines 16 . This occurs both in the case where the two nodes 10 and 20 use two different clocks and in the case where the two nodes use one and the same clock. The master node is responsible for “writing” or storing new data in a FIFO queue 30 , getting them to travel on an input line 12 , while the slave node 20 is responsible for “reading” or extracting the data stored in the queue 30 through an output line 14 . The master node 10 thus works at a first end of the FIFO queue 30 , while the slave node 20 works at the other end.
[0006] The presence of the FIFO queue 30 serves to enable co-existence of the two domains with different clock frequency. The FIFO queue 30 can be in particular a buffer used for regulating the flow of data in the communication between devices that work at different rates. It will on the other hand be appreciated that, in on-chip communication systems, the use of buffers is not necessarily linked to the need to regulate the flow of data between devices that work at different speeds. Other examples of possible use of buffers are: protocol conversion, packeting as in the case of network-on-chip, or conversion of data size.
[0007] The module designated in FIG. 1 by the reference number 25 represents the prediction, or look-ahead, unit. The approach here hypothesized envisages a parallel check of all the data stored in the FIFO queue 30 . Each module contained in the unit 25 , and designated by the reference number 40 , is fundamentally a comparator module designed to compare the values present on its inputs 42 , 44 with the purpose of selecting and issuing at output 46 the desired value (which can be a value sought, the maximum value, or the minimum value). The value selected by the comparator 40 is then made available at output and used as input for the next comparator 40 in the cascade, which compares it with a next element in the FIFO queue 30 . At the end of all the comparisons, the value sought is made available by the unit 25 at output on the line 18 .
[0008] This approach may prove, however, very slow and costly: in fact, for a queue of size N, N−1 comparators are used and there is a long critical path provided by the cascade of the comparators. Furthermore, this approach may prove far from flexible in so far as the length of the critical path and the production cost increase with the increase of the length of the queue.
SUMMARY OF THE INVENTION
[0009] On the basis of the above premises, there emerges the need to have available an efficient, low-cost, and high-performance mechanism for executing the look-ahead operation in a queue, such as for example a FIFO queue. Such an approach is frequently required by components present in the system that are located downstream of the queue, for example for anticipating execution of a given task. The look-ahead technique substantially implies the fact of investigating the contents of a memory, for example to identify the maximum or minimum value of a subset of bits or for detecting the presence or otherwise of a given value within the queue, without carrying out an exhaustive check on the contents.
[0010] An object of the invention is to provide an approach that is able to satisfy such requirements. According to the invention, these and other objects are provided by a method for managing a queue, such as for example a FIFO queue, and executing a look-ahead function on the data contained in the queue that includes associating to the data in the queue respective state variables, the value of each of which represents the number of times a datum is present in the queue. The look-ahead function is then executed on the respective state variables, preferentially using a number of state variables equal to the number of different values that may be assumed by the data in the queue. The look-ahead function can involve identification of the presence of a given datum in the queue and is, in that case, executed by verifying whether among the state variables there exists a corresponding state variable with non-nil value. It is also possible to organize the state variables in a monotonically ordered sequence in which the position of each state variable corresponds to the datum to which it is associated. The look-ahead function that involves identification of the datum in the queue having maximum value or minimum value can in this case be executed by identifying the datum as the one corresponding to the state variable of non-nil value occupying one of the end positions in the ordered sequence.
[0011] The invention also refers to a corresponding device, as well as to a computer program product that can be loaded into the memory of at least one computer and comprises portions of software code that are able to implement the method when the product is run on at least one computer.
[0012] As used herein, the reference to such a computer program product is understood as being equivalent to the reference to a computer-readable means containing instructions for control of the processing system for coordinating implementation of the method according to the invention. The reference to “at least one computer” is evidently meant to highlight the possibility of the present invention being implemented in a modular form and/or in a distributed form.
[0013] Various embodiments are suited to being applied to synchronous and asynchronous codes, likewise enabling at each cycle output of updated information from the queue.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will now be described, purely by way of non-limiting example, with reference to the annexed drawings, in which:
[0015] FIG. 1 is a schematic diagram illustrating a look ahead approach;
[0016] FIG. 2 is a block diagram of the main steps of an approach according to the present invention;
[0017] FIG. 3 is a schematic diagram illustrating an embodiment of the present invention with respect to a synchronous queue;
[0018] FIG. 4 is a schematic diagram illustrating another embodiment of the present invention with respect to an asynchronous queue; and
[0019] FIG. 5 is a schematic diagram illustrating an alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Illustrated in the ensuing description are various specific details aimed at providing an in-depth understanding of the embodiments. The embodiments can be implemented without one or more of the specific details, or with other methods, components, materials, etc. In other cases, known structures, materials, or operations are not illustrated or described in detail so that various aspects of the embodiments will not be obscured.
[0021] The reference to “an embodiment” or “one embodiment” in the framework of this description indicates that a particular configuration, structure or characteristic described in relation to the embodiment is comprised in at least one embodiment. Hence, phrases such as “in an embodiment” or “in one embodiment” that may be present in different points of this description do not necessarily refer to one and the same embodiment. Furthermore, particular conformations, structures, or characteristics can be combined adequately in one or more embodiments. The references are used herein only for convenience and hence do not define the sphere of protection or the scope of the embodiments.
[0022] In particular, it will be appreciated that, whereas the present description draws attention, above all for simplicity of reference, to the application to queues of a FIFO type, various embodiments are suited to being used in relation to queues of any type.
[0023] The general idea underlying various embodiments is that of managing a set of state variables, which, at each clock cycle, enable knowledge of the data stored in a queue, such as for example a FIFO queue. In this way, it is possible to avoid examination of all the data present in the FIFO queue by reading each item thereof, as in the case hypothesized with reference to FIG. 1 .
[0024] In various embodiments it is sufficient to examine the contents of some interfaces in which the state variables are updated only when a datum is written and/or read into/from the queue. These state variables are used for calculating the output value of the look-ahead mechanism.
[0025] In various embodiments, the state variable associated to a value that is present n times in the FIFO queue has a value equal to n, whereas the state variable associated to a value that is not present in the FIFO queue has a nil value. If the aim of the look-ahead function is to examine the presence or otherwise of a given value, it may be sufficient to have available just one state variable.
[0026] The state variable could be in principle also a variable of a Boolean type, in which associated to each of the two states is the condition of value present or value absent. A variable of a Boolean type does not on the other hand enable management of situations in which various occurrences of the value sought are present in the queue. In general, the different state variables enable tracing of the presence of different values, while the possibility of the single variable assuming different values enables management of the situation in which there are several occurrences of that particular value in the queue.
[0027] In the case where the aim is to find the maximum value or the minimum value among the data stored in a FIFO queue, the number of state variables can be equal to the number of values that the subset of data to be monitored can assume. Hence, there will be a state variable associated to each possible value that can be assumed by the elements in the queue. In this case, in various embodiments, it is possible to organize the state variables in a monotonically ordered sequence in which the position of each state variable corresponds to the data to which it is associated. The look-ahead function that entails identification of the datum in the queue having maximum or minimum value is performed by identifying the datum as the one corresponding to the state variable of non-nil value occupying one of the end positions in the ordered sequence.
[0028] It will be appreciated that the approach can be extended also to look-ahead operations of a more complex nature, such as for example determination of the average (for example, weighted average) of the values of the data in the queue. Each state variable identifies in fact a corresponding data value, and the value assumed by the variable indicates how many times (never, once or else a number of times, and how many times) the value is present. In fact, with the approach described herein, the set of the state variables, and the values assumed thereby, constitute in practice a “histogram” of the contents of the queue designed to be updated whenever a value is written (entered) in and/or read (extracted) from the FIFO queue.
[0029] In various embodiments, during each clock cycle, only the value of a state variable is incremented or decremented by one unit. As has been seen, the state variables can be obtained, for example, via counters, and each counter can be able to count up to a value equal to the length of the FIFO queue (in the case where stored in the FIFO queue are values that are all equal, the state variable associated to the value will assume a value equal to the length of the queue).
[0030] The steps of the example of embodiment considered herein are illustrated with reference to the flowchart of FIG. 2 and are executed at each clock cycle to obtain at output the result of the look-ahead scanning. Detected in step 50 is a write/read event that concerns the FIFO queue 30 . In the step 52 the datum is decoded and control passes to the next selection step 54 . In the case of a write operation, in step 56 the state variable addressed by the index Wi and regarding write operations is decremented. Instead, in the case of a read operation, in step 58 a state variable addressed by the index Ri and regarding read operations is incremented. Finally, in the case of a combined read and write operation, in step 60 the state variable addressed by the index Ri is incremented, and in a step 62 the state variable addressed by the index Wi is decremented.
[0031] In any case, at the end of these operations of updating of the state variables it is possible to continue with the step 64 in which the index of the block of the FIFO queue that contains the maximum value or the minimum value is identified. In particular, in step 64 a the maximum index from among the non-nil variables is sought, and this index identifies the position in which the maximum value is located. In like manner, in a step 64 b the minimum index from among the non-nil variables is sought, and this index identifies the position in which the minimum value is located. At output from step 64 there is the index that identifies the position of the value sought. Finally, in step 66 the index is encoded and at the next step 68 the maximum value/minimum value sought is made available.
[0032] In practice, synchronous queues and asynchronous queues are used, and in what follows the different architectures of the units for execution of the look-ahead operations will be described in detail. With reference to FIGS. 3 and 4 , two possible embodiments are illustrated in the synchronous case and in the asynchronous case, respectively. As compared to the approach illustrated in FIG. 1 , the cascade of comparator modules is replaced by a series of modules, the functions of which will be described below.
[0033] In the more general case, the FIFO queue is able to manage the control flow both at the input interfaces and at the output interfaces (usually this function is based upon a validation and acknowledgement protocol).
[0034] The modules 70 and 72 represent, respectively, a module for detection of a write operation and a module for detection of a read operation. In particular the modules 70 and 72 used for detecting write/read operations are combinational circuits that detect, respectively, whether the data are written or read in/from the FIFO queue. Their function depends upon the particular protocol for control of the flow implemented by the FIFO queue. For a flow-control protocol based upon the validation and acknowledgement (valid/ACK) paradigm, this circuit amounts to an AND logic port.
[0035] The modules C 1 , C 2 , . . . CK contained in the module 76 are counter modules. The number of counters K is equal to the number of the possible values that the X bits present on the lines 12 a and 14 a can assume. Each counter present in the module 76 has a dimension equal to the value of the length of the FIFO queue. The output logic has the function of detecting when the output of the counter is other than zero.
[0036] The decoder module 74 provides: incrementing by one unit of the value contained in the counter identified via the X bits present on the line 12 a if a write operation is identified, i.e., if an enable signal arrives at input on the line 70 a; and decrementing by one unit of the value contained in the counter identified via the X bits present on the line 14 a if a read operation is identified, i.e., if an enable signal arrives at input on the line 72 a. The function of the encoder module 78 depends instead upon the particular type of look-ahead operation to be executed.
[0037] As mentioned previously, in various embodiments the number K of the counters C 1 , C 2 , . . . CK is equal to the number of values that the elements of the FIFO queue can assume. The counter C 1 is associated to the lowest value that can be present within the FIFO queue, while the counter CK is associated to the highest value that can be present within the FIFO queue. If a counter CJ is zero it means that the value associated thereto is not present in the FIFO queue. In fact, not necessarily all the possible values are present simultaneously in the queue. A single value can be repeated a number of times and others may not be present within the FIFO queue.
[0038] There are thus present K counters, and each counter other than zero indicates the presence in the FIFO queue of the value associated to the counter. Furthermore, if the contents of the counter is greater than 1 it means that the value is present a number of times in the FIFO queue (and this means that there will be at least one nil counter).
[0039] In the case where the maximum value is sought, the output of the encoder 78 corresponds to the input value other than zero that is in the position on the extreme right; i.e., the counter other than zero with the highest index is sought (starting from K down to 1). Instead, in the case where the minimum value is sought, the output of the encoder 78 corresponds to the input value other than zero that is in the position on the extreme left; i.e., the counter other than zero with the lowest index is sought (starting from 1 up to K). Alternatively, to verify whether a given value is present or otherwise in the FIFO queue, it is sufficient to verify whether the output of the corresponding counter is other than zero.
[0040] In general, in one and the same look-ahead unit 25 , multiple decoding techniques can be implemented to obtain different look-ahead information at the same time The register module 80 (which is an optional module) has the purpose of re-timing the output, to break the combinational path and have a sufficient margin in terms of time. Tests conducted in 65-nm technology have shown that the encoder 78 can function properly at frequencies in the region of 700 MHz.
[0041] In the asynchronous case, the FIFO queues are generally written and read using different clocks that are not synchronized with one another. In this case, the embodiment appearing in FIG. 3 can be modified, as illustrated in FIG. 4 . Since, according to the approach proposed, the look-ahead logic mechanism functions in the domain of the clock referred to the write operations, there is the need to synchronize the inputs of the decoder module 74 (i.e., the ones present on the right in FIG. 4 ) with the output of the encoder module 78 (i.e., the look-ahead information present on the line 18 ).
[0042] For this purpose, it is possible to envisage the use of a synchronization chain, implemented according to the typical “brute force” approach, to be used at output from the encoder. The same approach in the case of the inputs of the encoder could cause the loss of data, and in turn the loss of data would alter the value of the state variables, thus damaging execution of the method.
[0043] In this regard, it is possible to generate, in a generator module 82 , a local read pointer 82 a in the first clock domain. The local pointer 82 a is used for reading the FIFO queue at a local level and is compared in a comparison module 84 with the synchronised pointer present on the line 82 b. The comparison serves to establish whether the FIFO queue has been read and whether the state variables are to be updated. Whenever the local pointer is different from the synchronised pointer, an enable signal 84 a that enables decrementing of the counter identified by the X bits present on the line 14 a is generated by the comparison module 84 . Finally, the output of the encoder 78 can be encoded according to a Gray code in a module 86 , synchronized in a module 88 , and decoded in a module 90 . Finally, presented hereinafter are some observations useful for understanding operation of various embodiments of the architecture of FIG. 4 .
[0044] The approach for managing asynchronous FIFO queues can envisage the read pointer 82 a being generated by the generator 82 in the read domain and being synchronized also with the write domain. When the local pointer 82 a differs from the synchronized one, the generator of the local pointer 82 can increment its output by one unit, and the decoder 74 can be authorized to decrement one of the counters 76 (the one selected via the value defined by the X bits coming from the output port of the local pointer 82 a of the FIFO queue). The local read port of the FIFO queue works in the first clock domain and is managed via the local pointer 82 a . The look-ahead information present on the line 18 can be synchronized via the typical brute-force approach, and, to avoid spurious values, also a Gray encoding can optionally be used.
[0045] According to the particular application, a different approach can be used, including the storage of the necessary information in a separate FIFO queue, as illustrated in FIG. 5 . In particular, a separate FIFO queue 35 is created, which is addressed through a separate bus 92 and which contains the information on the state variables. The approach is possible whenever there is no need to forward this information together with the inputs of the FIFO queue. The operation of writing in the separate FIFO queue is managed like that for the main FIFO queue (same write pointer WR and same control signals). The operation of reading of the separate FIFO queue in the synchronous case is managed like the one in the main FIFO queue, whereas in the asynchronous case it is managed via the local read pointer. However, in the asynchronous case there is no need to have a local read port in the main FIFO queue.
[0046] In general, the approach proposed is used when there is the need to analyze a particular subset of bits. Other typical applications are: management of the quality of service (QoS) in on-chip communications systems (for example, networks-on-chip); memory controllers for reorganizing and optimizing accesses to the memory; and central processing units (CPUs) of a general-purpose or specialized type for optimizing execution of a pipeline type.
[0047] The look-ahead approach described herein affords high performance (in terms of clocks) and a low cost (due to the area occupied). Furthermore, with the approach the look-ahead operation does not affect the performance of the queue. When working on an asynchronous queue, synchronization is guaranteed to limit the risk of conditions of meta-stability. Other possible applications are represented by traffic management in such a way as to reorganize the accesses to the memory areas for optimizing system performance.
[0048] Of course, without prejudice to the principle of the invention, the details and the embodiments may vary, even significantly, with respect to what has been described herein purely by way of example, without thereby departing from the scope of the invention, as defined by the annexed claims. In particular, it should be emphasized that, while the present description has concentrated attention on its application to queues of a FIFO type, various embodiments are suited to being used in relation to queues of any type. | A method for managing a queue, such as for example a FIFO queue, and executing a look-ahead function on the data contained in the queue includes associating to the data in the queue respective state variables (C 1, C 2 , . . . CK), the value of each of which represents the number of times a datum is present in the queue. The look-ahead function is then executed on the respective state variables, preferentially using a number of state variables (C 1, C 2 , . . . CK) equal to the number of different values that may be assumed by the data in the queue. The look-ahead function can involve identification of the presence of a given datum in the queue and is, in that case, executed by verifying whether among the state variables (C 1, C 2, . . . CK) there exists a corresponding state variable with non-nil value. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 62/344,887 filed on Jun. 2, 2016, entitled “PROBIOTIC AUGMENTATION OF ANTI-TUMOR ENDOTHELIUM IMMUNE RESPONSES”, the contents of which are incorporated herein by reference as though set forth in their entirety.
FIELD OF THE INVENTION
[0002] The invention pertains to field of probiotics. More particularly the invention pertains to the use of probiotics and prebiotics to augment immune responses towards tumor endothelial cells.
BACKGROUND
[0003] The immune system is comprised of multiple different cell types, biologically active compounds and molecules and organs. These include lymphocytes, monocytes and polymorphonuclear leukocytes, numerous soluble chemical mediators (cytokines and growth factors), the thymus, postnatal bone marrow, lymph nodes, liver and spleen. All of these components work together through a complex communication system to fight against microbial invaders such as bacteria, viruses, fungi and parasites, and tumor cells. Together, these components recognize specific molecular antigens as foreign or otherwise threatening, and initiate an immune response against cells or viruses that contain the foreign antigen. The immune system also functions to eliminate damaged or cancerous cells through active surveillance using the same mechanisms used to recognize microbial or viral invaders. The immune system recognizes the damaged or cancerous cells via antigens that are not strictly foreign, but are aberrantly expressed or mutated in the targeted cells.
SUMMARY OF THE INVENTION
[0004] A method of augmenting an immune response to tumor endothelial cells, the method may comprise the steps: a) obtaining a tumor endothelial antigen or composition of antigens; b) administering the tumor endothelial antigen or composition of antigens in an immunogenic manner to a host; and c) providing a probiotic and/or prebiotic mixture to the host being immunized. The antigen expressed on tumor endothelial cells may be selected from a group comprising: a) ROBO-4; b) VEGF-R2; c) FGF-R; d) CD105; e) TEM-1; f) survivin; g) CD93; h) CD 109; and i) ROBO 1-18. The antigenic composition may comprise of ValloVax. The probiotic administered may be Lactobacillus kefiranofaciens . The probiotic administered may be a strain of Lactobacillus kefiranofaciens selected from the group consisting of R2C2, INIX, K2, BioSP and ES1. The probiotic administered may be Bifidobacteria . The Bifidobacteria may be Bifidobacterium NCIMB 41676. The probiotic administered may be Lactobacillus salivarius . The prebiotic administered may be fructose polymers GF n and F m , either containing a glucose (G) end-group, or without a glucose end-group, and one or more component of a group of prebiotics consisting of modified or unmodified starch and partial hydrolysates thereof, partially hydrolysed inulin, natural oligofructoses, fructo-oligosaccharides (FOS), lactulose, galactomannan and suitable partial hydrolysates thereof, indigestible polydextrose, acemannan, various gums, indigestible dextrin and partial hydrolysates thereof, trans-galacto-oligosaccharides (GOS), xylo-oligosaccharides (XOS), beta-glucan and partial hydrolysates thereof, together if desired with phytosterol/phytostanol components and their suitable esters, and if desired other plant extracts, mineral components, vitamins and additives. The probiotic administered may be selected from a group comprising: a) Lactobacillus ; b) Leuconostoc ; c) Pediococcus ; d) Lactococcus ,; e) Aerococcus ; f) Carnobactehum ; g) Enterococcus ; h) Oenococcus ; i) Teragenococcus ; j) Vagococcus , and h) Weisella. The probiotic bacteria may be selected from a group, alone or in combination, comprising: a) Streptococcus thermophiles ; b) Lactobacillus reuteri ; c) Bifidobacterium bifidium ; d) Latobacillus acidophilus ; and e) Latobacillus casei.
DETAILED DESCRIPTION OF THE INVENTION
[0005] In one embodiment, specific probiotic bacteria are administered individually or in combination with tumor endothelial antigens, or polyvalent mixtures containing tumor endothelial antigens. In one embodiment, lactic acid bacterium and/or Bifidobacterium are administered at a concentration of 10(6) to 10(12) colony forming units (CFU) of bacteria per gram of support material, and more particularly from 10(8) to 10(12) CFU of bacteria/gram of support material, preferably 10(9) to 10(12) CFU/gram of support material for the lyophilized form. In the specific embodiment, said bacterium is administered orally, at a frequency sufficient to induce immune modulation. Specifically, immune modulation comprises upregulation of Th1 cytokines, and ability of vaccination with tumor endothelial specific antigens or composition of antigens. In one embodiment, ValloVax is administered subsequent to initiation of probiotic treatment. In one embodiment, administration of probiotics is performed daily for two weeks prior to ValloVax immunization.
[0006] Suitably the lactic acid bacterium and/or Bifidobacterium used in accordance with the present invention may be administered at a dosage of from about 10 6 to about 10 12 CFU of microorganism/dose, preferably about 10 8 to about 10 12 CFU of microorganism/dose. By the term “per dose” it is meant that this amount of microorganism is provided to a subject either per day or per intake, preferably per day. For example, if the microorganism is to be administered in a food product (for example in a yoghurt)—then the yoghurt will preferably contain from about 10 8 to 10 12 CFU of the microorganism. Alternatively, however, this amount of microorganism may be split into multiple administrations each consisting of a smaller amount of microbial loading—so long as the overall amount of microorganism received by the subject in any specific time (for instance each 24 hour period) is from about 10 6 to about 10 12 CFU of microorganism, preferably 10 8 to about 10 12 CFU of microorganism.
[0007] In accordance with the present invention, an effective amount of at least one strain of a microorganism may be at least 10 6 CFU of microorganism/dose, preferably from about 10 6 to about 10 12 CFU of microorganism/dose, preferably about 10 8 to about 10 12 CFU of microorganism/dose. In one embodiment, preferably the lactic acid bacterium and/or Bifidobacterium used in accordance with the present invention (such as a strain of Lactobacillus spp.; for example a strain of Lactobacillus acidophilus, Lactobacillus salivarius and/or Lactobacillus plantarum and/or a strain of Bifidobacterium spp., such as a strain of Lactobacillus acidophilus or Lactobacillus salivarius , for example Lactobacillus acidophilus strain such as NCFM or Lactobacillus salivarius strain 33) such as a strain of Bifidobacterium animalis subsp. lactis, for example Bifidobacterium animalis subsp. lactis strain 420 (B420)) may be administered at a dosage of from about 10 6 to about 10 12 CFU of microorganism/day, preferably about 10 8 to about 10 12 CFU of microorganism/day. Hence, the effective amount in this embodiment may be from about 10 6 to about 10 12 CFU of microorganism/day, preferably about 10 8 to about 10 12 CFU of microorganism/day.
[0008] The probiotic mixtures may be used according to the present invention in the form of solid or liquid preparations or alternatives thereof. Examples of solid preparations include, but are not limited to tablets, capsules, dusts, granules and powders which may be wettable, spray-dried or freeze-dried. Examples of liquid preparations include, but are not limited to, aqueous, organic or aqueous-organic solutions, suspensions and emulsions. Suitable examples of forms include one or more of: tablets, pills, capsules, ovules, solutions or suspensions, which may contain flavouring or colouring agents, for immediate-, delayed-, modified-, sustained-, pulsed- or controlled-release applications. By way of example, if the composition of the present invention is used in a tablet form—such for use as a functional ingredient—the tablets may also contain one or more of: excipients such as microcrystalline cellulose, lactose, sodium citrate, calcium carbonate, dibasic calcium phosphate and glycine; disintegrants such as starch (preferably corn, potato or tapioca starch), sodium starch glycoliate, croscarmellose sodium and certain complex silicates; granulation binders such as polyvinylpyrrolidone, hydroxypropylmethylcellulose (HPMC), hydroxypropylcellulose (HPC), sucrose, gelatin and acacia; lubricating agents such as magnesium stearate, stearic acid, glyceryl behenate and talc may be included. Furthermore, examples of nutritionally acceptable carriers for use in preparing the forms include, for example, water, salt solutions, alcohol, silicone, waxes, petroleum jelly, vegetable oils, polyethylene glycols, propylene glycol, liposomes, sugars, gelatin, lactose, amylose, magnesium stearate, talc, surfactants, silicic acid, viscous paraffin, perfume oil, fatty acid monoglycerides and diglycerides, petroethral fatty acid esters, hydroxymethylcellulose, polyvinylpyrrolidone, and the like. Preferred excipients for the forms include lactose, starch, a cellulose, milk sugar or high molecular weight polyethylene glycols.
[0009] In one embodiment, probiotic bacteria are administered in the form of a nutraceutical. Nutraceuticals, whether in the form of a liquid extract or dry composition, are edible and may be eaten directly by humans or mammals. Said nutraceuticals are preferably provided to humans in the form of additives or nutritional supplements e.g., in the form of tablets of the kind sold in health food stores, or as ingredients in edible solids, more preferably processed food products such as cereals, breads, tofu, cookies, ice cream, cakes, potato chips, pretzels, cheese, etc., and in drinkable liquids e.g., beverages such as milk, soda, sports drinks, and fruit juices. Thus, in one embodiment a method is provided for enhancing the nutritional value of a food or beverage by intermixing the food or beverage with a nutraceutical in an amount that is effective to enhance the nutritional and probiotic or immune modulatory value of the food or beverage. In one embodiment, a flavoring agent is added. Preferred flavoring agents include sweeteners such as sugar, corn syrup, fructose, dextrose, maltodextrose, cyclamates, saccharin, phenyl-alanine, xylitol, sorbitol, maltitol, and herbal sweeteners such as Stevia. Examples of foods into which probiotics useful for the practice of the invention can be incorporated into include soft drinks, a fruit juice or a beverage comprising whey protein, health teas, cocoa drinks, milk drinks and lactic acid bacteria drinks. Probiotic bacteria may be administered together with agents known to enhance efficacy and retention of probiotics, including [0035] In a further embodiment of the present invention various extracts and plant powders are incorporated into our compositions, depending on the desired properties according to the end use of said compositions. These compositions according to the present invention can be characterized in that in addition to the discussed prebiotics and phytosterols and lecithins the said further plant extracts or powders are one or more of those of Panax ginseng (red, Korean ginseng), Panax ginseng (white, Chinese ginseng), Rhodiola rosea (golden root), Panax quinquefolium (American ginseng), Eleutherococcus senticosus (Siberian ginseng), Cynara scolymus (artichoke), Uncaria tomentosa (Cat's claw), Lepidium meyenii (maca, Peruvian ginseng), Paullinia cupana (guarana), Croton lechleri (Sangre de Grado), Whitania somnifera (ashwagandha, Indian ginseng), Panax japonicus (Japanese ginseng), Panax vietnamensis (Vietnamese ginseng), Panax trifolius, Panax pseudoginseng, Panax notoginseng, Malpighia glabra (acerola), Ylex paraguayiensis (Yerba mate), Astragalus membranaceus (astragalus), Stevia rebaudiana (stevia), Pfaffia paniculata (Brazilian ginseng, suma), Ginkgo biloba, Tabebuia impetiginosa (Pau d'arco), Echinacea purpurea, Peumus boldus (boldo), Gynostemma pentaphyllum (Jiaogulan, also known as Southern Ginseng or Xiancao), Sutherlandia frutescens (African ginseng), Aloe vera (aloe), Cistanche salsa, Cistanche deserticola (and other Cistanche sp.), Codonopsis pilosula (“poor man's ginseng.”), Nopal opuntia (Prickly pear cactus), Citrus sinensis (Citrus aurantium) and other members of the citrus family (lemon, lime, tangerine, grapefruit), Camelia sinensis (tea), Plantago psyllium (psyllium), Amaranth edulis and other amaranth sp. (amaranth), Commiphora mukul (guggul lipid), Serenoa repens, Serenoa serrulata (saw palmetto), Cordyceps sinensis (Cordycaps), Lentinula edodes (shitake), Ganoderma lucidium (Reishi), Grifola frondosa (maitake), Tremella fuciformis (Silver ear), Poria cocos (Hoelen), Hericium erinaceus (Lion's Mane), Agaricus blazei (Sun mushroom), Phellinus linteus (Mulberry yellow polypore), Trametes versicolo , Coriolus versicolor (Turkey tails), Schizophyllum commune (Split gill), Inonotus obliquus (Cinder conl), oat bran, rice bran, linseed, garlic, Ceratonia siliqua (locust been gum or flour from the seeds of carob tree), Cyanopsis tetragonoloba (guar gum, EU Food additive code E412), Xanthomonas campestris (xanthan gum). These plant extracts and plant powders are capable to potentiate the bioactivity of these compositions based on prebiotics, phytosterols, lecithins, vitamins and minerals. In given cases it also adds other prebiotics to the aforementioned prebiotic mixtures. These can result in more pronounced bioactivities as prebiotics and also in the chosen other bioactivity directions.
[0010] The nutraceuticals described herein are intended for human consumption and thus the processes for obtaining them are preferably conducted in accordance with Good Manufacturing Practices (GMP) and any applicable government regulations governing such processes. Especially preferred processes utilize only naturally derived solvents. In contrast to nutraceuticals, the so-called “medical foods” are not meant to be used by the general public and are not available in stores or supermarkets. Medical foods are not those foods included within a healthy diet to decrease the risk of disease, such as reduced-fat foods or low-sodium foods, nor are they weight loss products. A physician prescribes a medical food when a patient has special nutrient needs in order to manage a disease or health condition, and the patient is under the physician's ongoing care. The label must clearly state that the product is intended to be used to manage a specific medical disorder or condition. An example of a medical food is nutritionally diverse medical food designed to provide targeted nutritional support for patients with chronic inflammatory conditions. Active compounds of this product are for instance one or more of the compounds described herein. The present invention thus relates to the use of an immuno-modulating properties of probiotics as related to prevention and/treatment of pregnancy complications. Thus said probiotics can be used in the preparation of a medicament, a vaginal suppository, medical food or nutraceutical to induce immune tolerance or immune modulation.
[0011] In some embodiments, the compositions according to the present invention comprise prebiotic components selected from fructose polymers GF n and F m , either containing a glucose (G) end-group, or without this glucose end-group and one or more component of a group of prebiotics consisting of modified or unmodified starch and partial hydrolysates thereof, partially hydrolysed inulin, natural oligofructoses, fructo-oligosaccharides (FOS), lactulose, galactomannan and suitable partial hydrolysates thereof, indigestible polydextrose, acemannan, various gums, indigestible dextrin and partial hydrolysates thereof, trans-galacto-oligosaccharides (GOS), xylo-oligosaccharides (XOS), beta-glucan and partial hydrolysates thereof, together if desired with phytosterol/phytostanol components and their suitable esters, and if desired other plant extracts, mineral components, vitamins and additives. The fructose polymers of GF n or F m structures (G=glucose; F=fructose; n>2; m>2) are linear fructose polymers having either a glucose (G) and −group, or being without this glucose and -group. Oligofructoses are consisted of 3 to 10 carbohydrate units. Above that, chicory inulin contains 10 to 60 carbohydrate units, typically with 27 carbohydrates (fructoses with our without one glucose end-group and a fructose chain). Other plants may produce different fructans. These fructans are capable to increase the number of colonized and planktonic bacteria in the large intestine. This results in a change that those bacteria that are less advantageous or may turn dangerous are suppressed by the higher probiotic colony of bacteria. Depending on the chain length of these fructans or other prebiotics, they can be fermented by probiotic bacteria at different positions in the colon. We have found that the longer inulins are capable to rich the distal colon and sigmoid colon and exert their anticancer actions in the positions where typically most of the cancerous problems occur. The occurrence of these cancers can be the result of various types of carcinogenesis. It has been demonstrated in the literature that directly induced chemical carcinogenesis can be greatly reduced by probiotic bacteria. The prebiotic compositions of our invention can corroborate this effect by considerably increasing the number of Bifidocateria and other beneficial probiotic strains. The local chemical carcinogenesis can also be the result of the formation of secondary bile acids. These secondary bile acids are often formed upon the action of enzymes produced by resident Clostridia . By probiotic suppression of the number of these bacteria according to the invention, the chance of secondary bile acid formation can also be reduced. This can be demonstrated by measuring the faecal primary/secondary bile acid ratio. Other prebiotics can be selected from a group of prebiotics consisting of various gums (guar gum, xanthan gum, locust been gum), carob seed flour, oat bran, rice bran, barley, modified or unmodified starch and suitable partial hydrolysates thereof, partially hydrolysed inulin, natural or synthetic/biosynthetic oligofructoses, fructo-oligosaccharides (FOS), lactulose, galactomannan and suitable hydrolysates thereof, indigestible polydextrose, indigestible dextrin and partial hydrolysates thereof, trans-galacto-oligosaccharides (GOS), xylo-oligosaccharides (XOS), acemannan, lentinan or beta-glucan and partial hydrolysates thereof, polysaccharides P and K (PSP, PSK), tagatose, various fungal oligosaccharides and polysaccharides, together with other components.
[0012] Before or during the tumor endothelium vaccination protocol, the subjects are subjected to radiation directed at the tumor or, in some cases, to whole body irradiation. The effect of this radiation treatment is to induce remodeling of the vasculature so that extravasation of effector T cells into the tumor is enhanced. If the tumor to be treated is not a solid tumor or a tumor with defined lesions, this aspect of the protocol is optional and generally unnecessary. However, when radiation is utilized, probiotics are utilized to repair immune responses before vaccine administration. Additionally, prebiotics may be administered prior to irradiation.
[0013] The effect of radiation is to ease the entry of the effector T cells elicited by the vaccine into solid tumors, so that the radiation can be administered immediately before or during the vaccination protocol. The level of radiation dosage will depend on whether the tumor is targeted directly or whole body radiation is employed and on the level of remodeling that needs to be effected. The radiation schedule can be integrated with the schedule for administration of the vaccine and with the schedule for the administration of anti-CTLA- 4 antibody that modulates the effect of Tregs. Each of the radiation treatments may be scheduled at a time selected to correspond to a particular administration of the vaccine and/or the Tregs modulator. In aspects of the invention, immunostimulatory oligonucleotides are administered together with probiotics. The immunostimulatory oligonucleotides can encompass various chemical modifications and substitutions, in comparison to natural RNA and DNA, involving a phosphodiester internucleoside bridge, a .beta.-D-ribose unit and/or a natural nucleoside base (adenine, guanine, cytosine, thymine, uracil). Examples of chemical modifications are known to the skilled person and are described, for example in Uhlmann E. et al. (1990), Chem. Rev. 90:543; “Protocols for Oligonucleotides and Analogs” Synthesis and Properties & Synthesis and Analytical Techniques, S. Agrawal, Ed., Humana Press, Totowa, USA 1993; Crooke, S. T. et al. (1996) Annu. Rev. Pharmacol. Toxicol. 36:107-129; and Hunziker J. et al., (1995), Mod. Synth. Methods 7:331-417. | Augmenting or stimulating an immune response, to tumor endothelial cells, by: a) obtaining a tumor endothelial antigen or composition of antigens; b) administering said tumor endothelial antigen or composition of antigens in an immunogenic manner to a host; and c) providing a probiotic and/or prebiotic mixture to said host being immunized. | 0 |
[0001] This is a continuation of co-pending parent application Ser. No. 11/125,200, filed May 10, 2005, itself a continuation of grandparent co-pending application Ser. No. 09/666,856, filed Sep. 21, 2000, now allowed.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of common networks for data communication and telephony, and, more specifically, to the networking of telephone sets within a building over digitally oriented local area network wiring, simultaneously with the data transmission.
BACKGROUND OF THE INVENTION
[0003] Small office and business environments commonly employ a multiplicity of work cells, each equipped with a telephone set and a computer. Two separate networks are usually employed for communication among the cells and between them and the outside world—a telephone network, connecting between the telephone sets and outside telephone lines, and a so-called local area network (LAN), connecting the computers among themselves and to outside network lines.
[0004] The tern computer or personal computer will be understood to include a workstation or other data terminal equipment (DTE) or at least one digital device capable of inputting and outputting data, whereby each computer includes an interface for connection to a local area network (LAN), used for digital data transmission; any such device will also be referred to as a remote digital device. The term telephone set will be understood to include any device which can connect to a PSTN (Public Switched Telephone Network), using telephony band signals, such as fax machine, automatic answering machine or dial-up modem; any such device will also be referred to as a remote- or local telephone device.
[0005] Such an environment is depicted in FIGS. 1 a and 1 b, which show a typical small office/business configuration, requiring two separate and independent networks. FIG. 1 a shows a telephony network 10 comprising a PABX (Private Automatic Branch Exchange) 11 , connected via lines 12 a, 12 b, 12 c and 12 d to telephone devices 13 a, 13 b, 13 c and 13 d respectively. The telephone are of the POTS (Plain Old Telephone Service) type, requiring each of the connecting lines 12 to consist of a single pair of wires.
[0006] FIG. 1 b shows a local area network (LAN) 15 for allowing communication between computers. Such a network comprises a hub (or switching hub) 16 , connected via lines 17 a, 17 b, 17 c and 17 d to computers 18 a, 18 b, 18 c and 18 d respectively. Popular types of LANs are based on the IEEE802.3 Ethernet standard, using 10BaseT or 100BaseTX interfaces and employing, for each connecting line 17 , two twisted pairs of wires—one pair for transmitting and one pair for receiving.
[0007] Installation and maintenance of two separate networks is complicated and expensive. It would therefore be advantageous, especially in new installations, to have a combined wiring network system that serves both telephony and data communication requirements.
[0008] One approach is to provide a LAN only, which selves for normal inter-computer communication, and make it serve also for telephony. One general method for this approach, in common usage today, utilizes so-called Voice-Over-Internet-Protocol (VoIP) techniques. By such techniques, known in the art, telephone signals are digitized and carried as data in any existing LAN. Systems employing such techniques are, however, complex and expensive, and the quality of the voice carried by currently available technology is low.
[0009] Another, opposite approach is to utilize an existing telephone infrastructure for simultaneously serving as both telephone and data networking. In this way, the task of establishing a new local area network in a home or other building is simplified, because there are no additional wires to install.
[0010] U.S. Pat. No. 4,766,402 to Crane teaches a way to form a LAN over two-wire telephone lines, but without the telephone service.
[0011] The concept of frequency division multiplexing (FDM) is well-known in the art, and provides a means of splitting the inherent bandwidth of a wire into a low-frequency band, capable of carrying an analog telephony signal, and a high-frequency band, capable of carrying data or other signals. Such a technique, sometimes referred to as ‘data over voice’, is described, for example, in U.S. Pat. Nos. 5,896,443, 4,807,225, 5,960,066, 4,672,605, 5,930,340, 5,025,443 and 4,924,492. It is also widely used in xDSL systems, primarily Asymmetric Digital Subscriber Loop (ADSL) systems.
[0012] A typical system employing FDM is illustrated in FIG. 2 , which shows schematically a combined telephony/data network 20 , providing in this case connections to two work cells by means of corresponding two cables 12 a and 12 b, each comprising a single twisted pair of wires. The lower part of the spectrum of cable 12 a is isolated by Low Pass Filters (LPF) 22 a and 22 b, each connected to a respective end of the cable. Similarly, the higher part of the spectrum is isolated by respective High Pass Filters (HPF) 21 a and 21 b. The telephony network uses the lower spectrum part by connecting the telephone 13 a and the PABX 11 to the respective LPFs. In order to use the higher part of the spectrum for data communication, telephone-line modems 23 a and 23 b are respectively connected to the HPFs 21 a and 21 b at both cable ends. Hub 16 connects to modem 23 a, while, on the user side, modem 23 b connects to computer 18 a, thus offering connectivity between the computer and the hub. The spectrum of the other cable 12 b is similarly split and cable 12 b connects telephone set 13 b to PABX 11 via LPFs 22 c and 22 d, while computer 18 b connects to hub 16 via modem 23 d, coupled to HPF 21 d, and modem 23 c, coupled to HPF 21 c. Additional telephones 13 and computers 18 can be added in the same manner. This prior-art concept is disclosed in U.S. Pat. No. 4,785,448 to Reichert et al. (hereinafter referred to as “Reichert”) and U.S. Pat. No. 5,841,841 to Dodds et al. (hereinafter referred to as “Dodds”). Both Reichert and Dodds suggest a method and apparatus for applying frequency domain/division multiplexing (FDM) technique for residential telephone wiring, enabling simultaneously carrying telephone and data communication signals, as described above.
[0013] Network 20 , employing an FDM method, typically requires two modems (such as 23 a and 23 b in FIG. 2 ) for each connected cell. Such modems are complex and expensive. In addition, the low communication quality of a typical telephone line, which was designed to carry low-frequency (telephony) signals only, limits both the data-rate and the distance of the data communication.
[0014] The concept of forming a phantom channel to serve as an additional path in a two wire-pairs communication system is known in the art of telephony, and disclosed in several patents, classified under U.S. Class 370/200. Commonly, such a phantom channel path is used to carry power to feed remote equipment or intermediate repeaters. In some prior-art systems, exemplified by U.S. Pat. Nos. 4,173,714, 3,975,594, 3,806,814, 6,026,078 and 4,937,811, the phantom channel is used to carry additional signals, such as metering and other auxiliary signals. Thus, all such systems use the phantom channel only as means for helping the communication service over the main channels. None of the mentioned prior-art uses the phantom channel for carrying an additional communication type of service, or for functionally combining two distinct networks.
[0015] It would thus be desirable to allow a data networking system to simultaneously also provide telephone service without any additional wiring.
SUMMARY OF THE INVENTION
[0016] It is an object of the invention to allow a data networking system to simultaneously also provide telephone service without any additional wiring.
[0017] This object is realized in accordance with a broad aspect of the invention by a communication network for providing simultaneous digital data- and analog telephone communication between a central location and at least one remote location, the communication network comprising:
[0018] a central digital device,
[0019] a central telephone device and,
[0020] for each remote location—a remote digital device, a remote telephone device and a cable having a remote end at the respective remote location and a near end at the central location;
[0021] said cable including at least two pairs of conductors, each pair operative as a data channel for carrying data signals between said remote digital device and said central digital device and said at least two pairs cooperatively forming a phantom channel, operative to carry telephone signals between said remote telephone device and said central telephone device.
[0022] Conventional data networks use a four-conductor circuit arrangement providing two communication channels between two units. For example, in a local area network based on Ethernet 10BaseT or 100BaseTX, two pairs of conductors are employed between a hub and DTE such as a computer. By means of the invention, POTS connection, such as between exchange and telephone apparatus, is accomplished simultaneously over the same four conductors used for the two communication channels without interference. The POTS service communication is accomplished via a phantom circuit arrangement over the four conductors.
[0023] Such configuration can be employed within small office or small business, wherein single wiring infrastructure is used for distributing both data and telephone signals from a central location, including a hub and an exchange to a remote station, each such station comprising a telephone unit and a data unit (e.g. desktop computer).
[0024] The present invention also provides a circuit arrangement wherein a cable that includes two twisted-conductor pairs provides both a two-way data communication channel for a connected computer and, simultaneously, a path for POTS signal to and from a connected telephone set, using the phantom channel method. In the preferred embodiment, the data communication channel consists of an Ethernet IEEE802.3 LAN channel and 10BaseT, or 100BaseTX, interfaces.
[0025] According to the invention, each two-conductor pair is terminated at each of its ends with a center tapped primary transformer winding (hereinafter cable-side winding), whereby each conductor of the pair is connected to a respective end of the cable side winding. Each winding is inductively coupled to a secondary winding (hereinafter referred to as equipment side winding), whose ends are connected to another pair of conductors that form the continuation channel for the data carrying signal, wherein the equipment side winding is connected to the data communication equipment. The center taps of each of the two primary winding at any end of the cable are connectable to the respective conductors of a telephone circuit, to carry the POTS signals. Thus, the two pairs of conductors at opposite ends of the cable, through the center taps of the respective primary transformer windings, form first and second connections of the two conductor phantom channel, which is used for carrying the telephone signal.
[0026] The invention can be implemented by means of two modules—one at each end of the two-conductor-pairs cable. Each module comprises two transformers, with a center-tap in the primary (cable side) winding. The module retains the two-pair data communication capability, while simultaneously including a phantom channel via the center-tap connections, for telephone service. The phantom channel can be accessed via a connector in the module. The module can be a stand-alone unit, or integrated within any unit in the network, such as a digital network hub, a telephone exchange, a server computer or telephone set. Alternatively, the module can be integrated within a wall outlet connected to one or both ends of the cable.
[0027] In another embodiment, the modules form a kit, which is used to upgrade an existing local area network to support telephone networking also.
[0028] The invention can be used in a small office or small business environment, which has a central location that comprises a telephone exchange and a digital network concentration unit (such as a hub, a switch or a router), connected to multiple remote work stations via LAN wiring.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:
[0030] FIGS. 1 a and 1 b show respectively a common prior art telephone and Local Area Network configuration as used within a small office or a small business;
[0031] FIG. 2 shows a prior art telephone and local area networks using the telephone-wiring infrastructure;
[0032] FIG. 3 shows a combined telephone and data communication network according to the present invention;
[0033] FIG. 4 shows schematically a data communications network having multiple phantom channels according to the present invention all sharing a common return;
[0034] FIG. 5 a shows schematically a computer modified according to the invention for direct coupling to a telephone set;
[0035] FIG. 5 b shows schematically a telephone set modified according to the invention for direct coupling to a computer;
[0036] FIG. 6 shows modified wall outlet that adds a phantom channel telephone service to an existing data communication system according to the present invention; and
[0037] FIGS. 7 a to 7 d show different views of an attachable wall plug connector that adds a phantom channel telephone service to an existing data communication system according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0038] In the following description it is to be noted that the drawings and descriptions are conceptual only. In actual practice, a single component can implement one or more functions; alternatively, each function can be implemented by a plurality of components and circuits. In the drawings and descriptions, identical reference numerals are use to indicate those components that are common to different embodiments or configurations.
[0039] FIG. 3 illustrates a preferred embodiment of the present invention. The network 30 is a part of an IEEE802.3 local area network, using 10BaseT interfaces. A hub 16 , defining a central location, is connected to a typical computer 18 a via a cable that includes two wire pairs 17 a 1 and 17 a 2 . Each pair is operative to carry data in one direction only, one pair, say 17 a 1 , canning data from the hub 16 to the computer 18 a, while the other pair, 17 a 2 , carries data in the other direction. FIG. 3 also shows a telephone set 13 a, associated with computer 18 a and preferably near it, and a telephone private automatic ranch exchange (PABX) 11 , which is preferably also at the central location. The term hub is used herein to represent any digital network concentrating unit and may equally refer to a switching hub, a router, a server computer or to any digital device having multiple data ports; any of these being also referred to herein as a central digital device. Similarly, PABX is used herein to represent any type of central telephone switching unit and will also be referred to as a central telephone device.
[0040] According to the invention, a signal transformer is inserted at each end of each wire pair, whereby, for example, transformer 31 a 1 is inserted at the end of wire pair 17 a 1 that is near hub 16 and transformer 31 b 1 is inserted at the end of wire pair 17 a 1 that is near computer 18 a. Similarly, transformers 31 a 2 and 31 b 2 are inserted at the ends of wire pair 17 a 2 that are near hub 16 and computer 18 a, respectively. The signal transformers bearing the prefix 31 are designed so that the signal attenuation via these transformers is negligible. Hence, the performance of the data communication network is fully retained, and the hub 16 continues to communicate fully with the computer 18 a in the usual manner. Such transformers are known in the art and are often used in LANs, in order to meet isolation and common-mode rejection requirements. Commonly, such signal transformers are equipped with a primary winding and a secondary winding both being untapped coils. In the invention, each signal transformer bearing the prefix 31 , say 31 a 2 has a primary winding 35 , whose ends are connected to the respective wires of the cable, and a secondary winding 36 , whose ends are connected to the respective system component (hub 16 or computer 18 a ).
[0041] However, unlike the conventional configuration for signal transformers, according to the present invention each primary winding 35 has a center-tap shown as 37 a 1 and 37 a 2 , for the two signal transformers 31 a 1 and 31 a 2 , respectively. PABX 11 is connected, via two respective wires 38 a, to the center-taps 37 a 1 and 37 a 2 of transformers 31 a 1 and 31 a 2 . Similarly, the telephone set 13 a is connected, via two respective wires 38 b, to the center-taps 37 b 1 and 37 b 2 of transformers 31 b 1 and 31 b 2 , respectively. In this configuration, the telephony signals are carried in a ‘phantom’ way together with the data communication signals, without any interference between the two. In practice, the hub side transformers 31 a 1 and 31 a 2 may be integrated to form a module 32 a, while the computer side transformers 31 b 1 and 31 b 2 may be integrated to form a module 32 b. while the network 30 has so far been described as supporting a single computer and a single telephone, additional work cells, each comprising a telephone and a computer can be supported, whereby each computer is connected with hub 16 through a corresponding two wire pairs cable, by inserting an additional set of modules 32 a and 32 b in each such cable.
[0042] While the invention has been described specifically for 10BaseT (10 Mb/s) interfaces, the invention can be equally applied to 100BaseTX (100 Mb/s) interfaces. Furthermore, the invention can be equally applied in any wired networking system using at least two wire pairs. Transformers can be used in all wired communication systems whose signals do not include direct current (DC) components. In systems that use four or more pairs of wires, such as those based on the evolving 1000BaseTX Ethernet standard, each two pairs can be used to form a single phantom channel. Thus, four pairs can form two phantom channels, each carrying one POTS circuit, by terminating each pair with a transformer as described above. Alternatively and preferably, as shown in FIG. 4 , three pairs 17 a 1 , 17 a 2 and 17 a 3 can each form a phantom channel with the fourth pair 17 a 4 , which serves as the common return path. In this case, each telephone circuit 13 a, 13 b and 13 c has one of its two wires connected to the center-tap 37 b 1 , 37 b 2 and 37 b 3 of the respective transformer 31 b 1 , 31 b 2 and 31 b 3 at the corresponding end of the respective pair and the other wire—to the center-tap 37 b 4 of the transformer 31 b 4 at the corresponding end of the common pair. More generally, with N pairs of conductors, each pair serving as a data channel, it is possible to similarly provide N−1 phantom channels for telephone service.
[0043] In the configuration shown in FIG. 3 the modules 32 a and 32 b are stand-alone modules, mechanically separate from other components in the network. However, also other configurations are possible. For example, the hub side module 32 a can be integrated, fully or in part, within the hub 16 . In such a case, the hub's existing data connection-unit (such as a distribution frame—for connecting thereto all line pairs) is preferably substituted by one that includes module 32 a; in addition, a telephone connector is provided, for connecting all telephone lines (whose other ends are connected to their respective center taps in module 32 a ) to the PABX. Alternatively, module 32 a can be similarly integrated within PABX 11 , whereby an appropriate connection with the hub is provided.
[0044] FIG. 5 a shows schematically an arrangement where the computer side module 32 b is integrated, fully or in part, within the computer 18 a. Thus, the secondary windings 36 of the transformers 31 a 1 and 31 a 2 are connected to receiver and transmitter circuitry 39 a and 39 b within the computer 18 a. The ends of the primary windings 35 of the transformers 31 a 1 and 31 a 2 are connected to a standard socket outlet 40 for connecting to the network. The center-taps 37 a 1 and 37 a 2 are connected to a standard telephone outlet 41 , enabling connection thereto of a telephone set such as designated 13 a in FIG. 3 .
[0045] FIG. 5 b shows schematically the complementary arrangement where the module 32 b is integrated the telephone set 13 a. Thus, the secondary windings 36 of the transformers 31 a 1 and 31 a 2 are connected to a standard outlet 42 for connecting thereto a computer such as designated 18 a in FIG. 3 . The ends of the primary windings 35 of the transformers 31 a 1 and 31 a 2 are connected to a standard socket outlet 43 for connecting to the network. The center-taps 37 a 1 and 37 a 2 are connected to telephone circuitry 44 , within the telephone set 13 a.
[0046] Alternatively, the computer side module 32 b can be integrated within a wall connector allowing direct or indirect connection to an existing wall socket outlet. Thus, such a wall connector can be constituted by a substitute wall socket having integrated therein a pair of signal transformers and two female outlets for connecting a computer and telephone thereto, respectively. Alternatively, the wall connector can be constituted by a plug connector having integrated therein a pair of signal transformers and two female outlets for connecting a computer and telephone thereto, respectively. Such a plug connector allows a computer and telephone to be connected to an existing wall socket outlet without requiring any modification thereto.
[0047] FIG. 6 shows the faceplate of a modified socket outlet 45 according to the invention. Two conductor pairs are connected to the outlet at the rear (not shown in the Figure), connected to the primary windings of two signals transformers housed in it (not shown in the Figure). The secondary windings of the transformers are connected to RJ-45 data connector 46 , while the center taps are connected to the RJ-11 telephony connector 47 . Such an outlet is physically similar in size, shape, and overall appearance to a standard outlet, so that such an outlet can be substituted for a standard outlet in the building wall. No changes are required in the overall LAN line layout or configuration. Such an outlet can easily substitute an existing standard data outlet to thus additionally provide telephony support. Thus a conventional outlet has a single female connector having two pairs of wiper contacts connected to the respective twisted-wire pairs for data transmission and reception. A computer is plugged into such a conventional outlet via a single male connector (plug) having four pins: two for handling data transmission and two for handling data reception. On inserting the plug into the socket outlets, the pins brush against the wiper contacts in the socket outlet, thus establishing electrical connection between the two.
[0048] The invention allows for the conventional outlet to be replaced by a modified outlet having therein a pair of signal transformers, the ends of whose respective primary windings are adapted to be connected to the ends of a respective conductor pair in the network. The secondary winding of each signal transformer is connected internally to a respective pair of wiper contacts of a first female connector. Thus, the ends of both secondary windings are connected to first female connector by means of four wiper contacts in total. The respective center-taps of each of the two primary windings are connected to a pair of wiper contacts in a second female connector proximate the first female connector. Thus, a computer can be connected, via four pins of a suitable jack plug, to the first female connector, while a telephone can be connected, via two pins of a suitable jack plug to the second female connector. The two wire pairs 17 a 1 and 17 a 2 are routed and connected to such an outlet, which will now comprise two faceplate connectors—a data connector (e.g. RJ-45 for 10BaseT) and a telephone connector (e.g. RJ-11).
[0049] Such an implementation requires that the socket outlets in an existing data network be replaced by a modified outlet according to the invention. FIGS. 7 a to 7 d show various views of a plug assembly 50 according to the invention for operation in 10BaseT or 100BaseTX environment that allows the invention to be implemented without requiring any modification to the data network or to the existing socket outlet. In use, the plug assembly 50 is plugged into a standard socket outlet and is retained therein by means of a latch 51 . The plug assembly 50 contains the module 32 b connected to separate data- and telephony socket outlets 52 and 53 in a similar manner to the modified socket outlet 45 described above with reference to FIG. 6 . A standard RJ45 jack plug 54 is connected to the module 32 b for mating with the wall outlet when plugged into its socket. The jack plug 54 thus includes two pairs of pins each connected to the primary winding of a respective signal transformer within the module 32 b. The secondary windings of the two signal transformers are connected to respective wiper contacts in the data-telephony socket outlet 52 . The respective center-taps of each of the primary windings are connected to a pair of wiper contacts in the telephony socket outlet 53 proximate the data-telephony socket outlet 52 . Cables from the computer and the telephone set terminate in standard jack plugs that are plugged into the respective data- and telephony socket outlets 52 and 53 within the plug assembly 50 . Thus, the plug assembly 50 obviates the need for any changes to be made to the existing infrastructure.
[0050] As mentioned above, 10BaseT and 100BaseTX interfaces, as well as other data communication interfaces, often include signal transformers in the line connection circuitry, in order to meet isolation and common-mode rejection requirements. In such cases, additional transformers, though possible, are not required and the method of the present invention can be implemented by adding center-tap connections to the respective windings of the existing transformers and using them to form a phantom channel, to serve for telephone connection in the manner described above. Alternatively, the existing transformers can be substituted by ones with center-taps as specified above.
[0051] It is noted that, while a phantom channel has been known in the art, its use in the system and method disclosed herein is novel, because:
[0052] (a) Local area networks (LANs) in general, and Ethernet networks in particular, currently do not employ phantom channels, nor is any configuration employing such channels specified in the IEEE802.3 standards; the concept is known in the realm of telephony only, which is very different from that of data communication LANs.
[0053] (b) Using a phantom channel itself to carry POTS service is not known in the art; rather, phantom channels are used only to carry power to remote units and/or management- or control signals to support the main service that is provided by the two conductor pairs.
[0054] While the invention is described above relating to hub units, it is clear that any other multi-port data communication device can be used, such as switch, router or gateway.
[0055] The present invention also embraces a method for upgrading an existing local area network (LAN) installation that includes a two-conductor pair cable between two digital devices, to also and simultaneously convey signals between two telephone devices, the method comprising:
(a) inserting a first pair of signal transformers having center-tapped primary windings at a first end of the cable, with respective ends of the primary windings connected to respective conductors of the cable; and (b) inserting a second pair of signal transformers having center-tapped primary windings at a second end of the cable, with respective ends of the primary windings connected to respective conductors of the cable;
[0058] thereby allowing respective secondary windings of each signal transformer to be connected to the digital devices and allowing the respective center-taps of the signal transformers to be connected to telephone equipment.
[0059] If the LAN already includes signal transformers that do not have center-taps, they are, in step (a) above, replaced by the specified transformers or, alternatively, a center-tap is added to each primary winding.
[0060] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. | A method and apparatus for enabling a local area network wiring structure to simultaneously carry digital data and analog telephone signals on the same transmission medium. It is particularly applicable to a network in star topology, in which remote data units (e.g. personal computers) are each connected to a hub through a cable comprising at least two pairs of conductors, providing a data communication path in each direction. Modules at each end of the cable provide a phantom path for telephony (voice band) signals between a telephone near the data set and a PBX, through both conductor pairs in a phantom circuit arrangement. All such communication paths function simultaneously and without mutual interference. The modules comprise simple and inexpensive passive circuit components. | 8 |
FIELD OF THE INVENTION
[0001] The present invention relates to a filter for a smoking article such as a cigarette.
BACKGROUND
[0002] The main function of smoking article filters is to remove some of the substances produced by combustion of the smokable material from the smoke flow as it is drawn by the smoker. Various types of filter constructions have been described.
[0003] As well as removing material from the gaseous flow drawn by the smoker, the filter may also be arranged to impart selected substances into the smoke for the purpose of modifying various characteristics. For example, filtration of smoke is generally thought to have a negative effect on the flavour and taste characteristics of the smoke and smoking article filters have been described that are arranged to impart flavourants into the smoke flow.
[0004] Menthol is used as a flavourant in a variety of products and is a popular flavourant for use in cigarettes, pipe tobacco, chewing tobacco, and other smoking materials. Menthol produces a cooling sensation when inhaled or consumed and is used extensively because of the refreshing cooling effect it imparts to tobacco smoke.
[0005] However, menthol has a high degree of volatility at room temperature, and this makes the menthol concentration difficult to control. It also poses problems in the packaging and handling of the smoking articles. Furthermore, smoking products containing menthol frequently have a short shelf life due to loss of menthol from the product during storage.
[0006] To overcome this problem, menthol derivatives or similar compounds that release menthol or menthol-like flavourants have been developed. However, such derivatives may suffer from one or more drawbacks. For example, they may not yield a sufficient quantity of free menthol upon use of the smoking article, they may be unstable or difficult to process, or the pyrolysis or hydrolysis products may be toxic, or may result in an unacceptable taste.
[0007] Smoking article filters have been described in which the smoke becomes flavoured as it is drawn due to the filter material having a flavouring agent such as menthol applied uniformly upon it. However, this means of flavouring the smoke has drawbacks including inconsistency of flavour provision, and complications during the manufacturing process, in particular, when one flavourant is exchanged for another.
[0008] To overcome this problem, smoking articles have been described in which a flavoured element is introduced into the filter, for example, menthol adsorbed on a support such as diatomaceous earth, from which the menthol is later released. However, it has often been the case that the flavoured element is not introduced in the correct amount or correct position to provide the optimal effect on the smoke. Generally such methods suffer from low menthol yields, and may result in unacceptable taste or appearance of the smoking product.
[0009] A modification to the approach of using a flavoured element is described in US 2005/0255978 which discloses an apparatus for manufacturing smoking article filters which have a thread loaded with flavourant passing along the central axis. In this way, greater control may be exerted over the position and amount of flavourant that is incorporated. The preferred material for the manufacture of the thread is cotton, although other materials such as cellulose acetate and rayon may also be used. Cotton thread has drawbacks as a material for providing flavourant, for example becoming discloured and unsightly during consumption of the smoking article. To overcome this problem the cotton may be dyed, however, dyes do not generally have regulatory approval, and may also leach into the surrounding filter material.
SUMMARY OF THE INVENTION
[0010] According to the present invention there is provided a filter for a smoking article, wherein said filter comprises at least one thread composed of material derived from a plant containing a naturally occurring tobacco flavourant.
[0011] The plant may be a member of the order Lamiales, which includes plants such as mint, lavender, lilac, olive, and jasmine. More specifically, the plant may be a member of the family Lamiaceae, which is also known as the family Labiatae, or the mint family, and includes many aromatic herbs such as basil, mint, rosemary, sage, savory, marjoram, oregano, thyme, lavender, and perilla. In particular, the plant may be of the genus Mentha , and may be of the species Mentha arvensis.
[0012] Threads composed from plant material such as this can have the added advantage of being naturally coloured. Consequently, the thread may be easily distinguished from the remainder of the filter material, giving the filter an interesting and attractive appearance, and making any discolouration of the thread or filter material less obvious.
[0013] To provide the desired level of flavour to the smoke, the thread may further comprise additional flavourant. Alternatively or additionally, flavourant may be added to the remaining filter material.
[0014] The thread may be between 0.2 mm and 5 mm in diameter, preferably between 0.4 mm and 3 mm in diameter, more preferably between 0.5 mm and 1.5 mm in diameter, and most preferably between 0.7 mm and 1 mm in diameter.
[0015] The invention also includes a method of making a filter for a smoking article. The method may involve inserting a thread comprising material from a plant containing a naturally occurring tobacco flavourant into a filter rod. The thread may be inserted into substantially the central cylindrical axis of the filter rod.
[0016] As used herein, the term “smoking article” includes smokable products such as cigarettes, cigars and cigarillos whether based on tobacco, tobacco derivatives, expanded tobacco, reconstituted tobacco or tobacco substitutes and also heat-not-burn products.
[0017] As used herein, the terms “flavour” and “flavourant” refer to materials which may be used to create a desired taste or aroma in a product.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] For a fuller understanding of the invention, reference is made to the single FIGURE of the accompanying drawing which illustrates an embodiment of a filter given by way of example, of a filter cigarette.
DETAILED DESCRIPTION
[0019] FIG. 1 shows a filter cigarette comprising a filter 1 and a tobacco rod 2 . Both the filter 1 and tobacco rod 2 are substantially cylindrical, being generally circular in cross-section, and have diameters which are of a similar size. A layer of tipping paper 3 is wrapped around the cigarette and holds the tobacco rod 2 and the filter 1 together in a longitudinally abutting relationship.
[0020] The filter is primarily composed from fibrous cellulose acetate filter material 4 encompassed by a layer of plugwrap (not shown) in a manner well known per se. Located within the filter material is a thin thread 5 which is manufactured from material derived from a plant of the species Mentha arvensis , a type of mint. The thread 5 is situated substantially in the diametric centre of the filter and extends from the mouth end 6 of the filter to the tobacco rod 2 in a generally linear configuration.
[0021] In use, negative pressure created by the user sucking on the mouth end 6 of the filter has the effect of drawing smoke along the tobacco rod 2 and through the filter 1 . As smoke passes through the filter 1 , particulate components of the smoke are retained by the cellulose acetate fibres, at least to some extent. Concurrently with the removal of particulate components, however, flavourants diffuse from the thread 5 , into the flow of smoke, and are thus sucked into the mouth of the user.
[0022] One method of introducing the thread 5 into the filter 1 is as follows. The filter 1 is manufactured using a process in which a supply of filter material is continuously advanced, the advancing material being continuously condensed to rod form, and the resulting rod being continuously cleaved into individual lengths. Incorporation of the thread 5 occurs as the continuous thread is directed into the centre of the filter material as or before its condensation to rod form. As a result the thread becomes incorporated in the body of the filter rod and extends continuously longitudinally thereof.
[0023] The amount of flavourant provided to the smoke by the thread is dependent on a number of factors including the thickness of the thread, the fine structure and the moisture content, and the concentration of flavourant in the plant matter chosen as the raw material.
[0024] The thread need not be located at the diametric centre of the filter, and so may be off-centre, and may even be situated substantially towards the circumferential edge of the filter. Two or more threads can be incorporated within the filter, for example between 2 and 20 threads, preferably between 3 and 15 threads, more preferably between 4 and 10 threads.
[0025] The thread may have additional flavourants entrained within for the purpose of enhancing or modifying the natural flavour provided by the plant material. In the case of a filter containing multiple threads, the threads within a filter may comprise the same or different flavourants. In some embodiments, the thread may be treated with a colourant prior to its incorporation into the filter for example, for the purpose of providing an interesting and attractive appearance to the mouth end 6 of the filter, to provide flavour identification (such as different colours for different flavours), or to mask any discolouration of the thread or filter material.
[0026] When colourants and/or flavourants are added to the thread, these agents are preferably applied to the or each thread immediately before the thread is incorporated in the filter material, for example, by directing the thread through a solution of the agent and then into the filter material as it is condensed. The solvent for the agent is chosen to be compatible with the filtering material and any other component of the filter product.
[0027] The filter 1 may comprise a ventilated filter, for example having a porous or perforated wrapper through which in use, external air is drawn to dilute the smoke drawn through the filter. Diluting air tends to travel along the peripheral region of the filter, so that the thread extending along the filter core, where the smoke concentration is highest, increases the possibility of diffusion of flavourant from the thread most effectively and economically.
[0028] The invention also includes further modifications and variations falling within the scope of the claims. For example, although the thread has been described as being made from mint, other suitable plants my be utilised and for example the plant may be a member of the order Lamiales, which includes plants such as mint, lavender, lilac, olive, and jasmine. More specifically, the plant may be a member of the family Lamiaceae, which is also known as the family Labiatae, or the mint family, and includes many aromatic herbs such as basil, mint, rosemary, sage, savory, marjoram, oregano, thyme, lavender, and perilla.
[0029] These plants may have beneficial qualities. For example, some of these plants are known to contain compounds which have anti-inflammatory properties.
[0030] The filter may be a composite filter comprising a plurality of abutted filter sections, for example at least two, preferably at least three filter sections, provided that at least one of the sections comprises a thread as herein described. Preferably the composite filter comprises a single section incorporating a thread as herein described, this section being preferably located at the mouth end of the filter. The filter sections of the composite filter not containing a thread may comprise one or a combination of cellulose acetate, polypropylene, paper or any other suitable material, and may alternatively or additionally comprise adsorbent material, for example, activated charcoal, a resin material such as amberlite or duolite, and/or catalytic material. | A filter for a smoking article such as a cigarette is provided comprising a body of smoke filtering material ( 1 ) and having a thread ( 5 ) incorporated therein. The thread is composed of material derived from a plant containing a naturally occurring tobacco flavorant. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to chemical process towers and, more particularly, to a method of and apparatus for cartridge tray sealing for chemical process towers.
2. History of the Prior Art
Distillation columns are utilized to separate selected components from a multi-component stream. Generally, such gas-liquid contact columns utilize either cartridge trays, packings or combinations thereof. In recent years the trend has been to replace the so-called "bubble caps" by sieve and valve trays in most trayed column designs, and the popularity of packed columns, either random (dumped) or structured packings has been utilized in combination with the trays in order to effect improved separation of the components in the stream.
Successful fractionation in the column is dependent upon intimate contact between liquid and vapor phases. Some vapor and liquid contact devices, such as trays, are characterized by relatively high pressure drop and relatively high liquid hold-up. Another type of vapor and liquid contact apparatus, namely structured high efficiency packing, has also become popular for certain applications. Such packing is energy efficient because it has low pressure drop and low liquid hold-up. However, these very properties at times make columns equipped with structured packing difficult to operate in a stable, consistent manner. Moreover, many applications simply require the use of trays.
When cartridge trays are the predominant column contacting devices, there is little need to be concerned about vapor distribution because pressure drop across the trayed column is high. For trayed towers with approximately 50 trays, a pressure drop on the order of 6 PSI (300 mmHg) is common in the prior art. This is, however, more than an order of magnitude greater than the kinetic energy generated by the incoming vapor. The velocity head of vapor entering the distillation column is often greater than 3 to 4 inches of water in refinery heavy oil fractionators whereas the velocity head is no more than 5 mm in chemical or gas treating columns. It is true, however, that when the trays of a 50 tray tower are replaced by packing, the pressure drop through the column is typically reduced by a full order of magnitude, to with on the order of 30 mmHg. This is especially true of structured packing such as that set forth and described in U.S. Pat. No. 4,604,247 assigned to the assignee of the present invention. If the kinetic energy of the feed vapor is kept at 10 mm or more, severe mal-distribution may occur.
Cartridge trays or distillation trays may be assembled in bundles of up to 15 or more trays in a tower. The bundles are inserted into the towers ranging in size from 6" to 36" in diameter. To seal the trays against vapor and liquid bypass, cartridge trays are designed with an edge seal on each tray. This sealing technique is extremely important in the design and operation of the tower. The basic theory of a distillation tray is to maintain a liquid level on the tray and allow the vapor to pass through an open area on the tray and through the liquid disposed thereabove. At the same time, the liquid is allowed to flow across the tray into a downcomer for passage to the tray below. This action is controlled by the design of the hole area in the tray floor. Hole area is calculated to maintain a certain vapor velocity and to achieve the proper vapor-liquid interaction. However, if leakage of liquid or bypassing of vapor occurs at the edge of the tray, the design conditions will be altered and the tray will not operate in accordance with the specification. For this reason the design and manufacture of the trays has received considerable attention.
The fabrication and assembly of cartridge tray tower shells are subject to a number of tolerance problems. For example, shells that are fabricated from rolled and welded plates formed into a round shell are affeoted by the heat of welding. When rolled and welded methods of fabrication are used, shell size and tolerance variations occur in the diameter and velocity at the shell flanges and nozzle locations as well as along the axial and circumferntial weld seams. In addition to the problems recited above, the irregularities in the shell surface may restrict movements of prior art tray sealing designs making it difficult or impossible to insert a tray bundle into a tower region where the deformation has occurred
A particularly effective cartridge tray design for process columns is the sieve tray. This tray is constructed with a large number of elongate apertures formed in the bottom surface. The apertures permit the ascending vapor to flow into direct engagement with the liquid that is flowing across the tray. When there is sufficient vapor flow upwardly through the tray, the liquid is prevented from running downwardly through the apertures (referred to as "weeping"). A small degree of weeping is normal in trays, while a larger degree of weeping is detrimental to the capacity and efficiency of a tray. A further discussion of cartridge trays and related aspects of process column operations may also be seen in U.S. Pat. No. 4,956,127, assigned to the assignee of the present invention.
In the assembly stage, the cartridge trays are generally placed in the process column atop support rings. The support rings are generally welded or otherwise permanently secured to the inside surface of the tower and provide mechanical support for the cartridge tray. The issue of sealing the cartridge tray to the column walls and/or the underlying support ring is always a consideration. Prior art approaches have included expandable metal rings which engage the cylindrical walls of the process column. However, out-of-round problems as well as manufacturing tolerance variations often prevent a uniform sealing therearound. It has also been observed that welding along the tower wall in conjunction with construction of tower internals often causes thermal deformation of the tower walls which further exacerbates the out-of-round condition. The utilization of inflexible sealing members against such a tower wall thus generates a myriad of sealing problems. To accommodate for out-of-round regions, more flexible sealing members have been proposed. In the main, the sealing members comprise gaskets and the like which elastically deform to accommodate shape variations. Unfortunately many of the materials for which the flexible gaskets are fabricated find the tower environment to be extremely hostile, and gasket deterioration is commonplace. For this reason, improved sealing member designs have included rings which have a higher degree of flexibility and many accommodate hostile environments. One such ring is set forth and shown in U.S. Pat. No. 4,255,363 wherein a ring is made from polytetrafluoroethylene (PTFE). In that prior art reference it is seen that the PTFE ring is assembled with means for adjusting the pressure of the seal against the tower wall and to accommodate for more effective sealing. Yet even the degree of flexibility afforded by PTFE or other synthetic fluorine material, in and of itself, may not always be sufficient for certain tolerance variations in the tower wall that could be accommodated by more flaccid structures. It would be an advantage, therefore, to overcome the problems of the prior art by providing a reliable, flexible seal that could accommodate both wise tolerance variations and the hostile environment of a chemical process tower.
The present invention provides such an advancement over the prior art by utilizing a teflon impregnated fiberglass gasket of generally flexible construction. The gasket is secured to the cartridge tray ring and presents a double lip outwardly thereof adapted for engaging the process tower wall. The lips are presented in an upwardly deflected orientation for providing a flexible sealing surface against the tower wall and permitting the build-up of liquid pressure thereagainst while preventing the passage of liquid and vapor therethrough and around the cartridge tray perimeter.
SUMMARY OF THE INVENTION
The present invention relates to sealing members for cartridge trays of chemical process towers. More particularly, one aspect of the present invention includes a teflon impregnated fiberglass gasket of generally flaccid construction secured to the outer perimeter of a cartridge tray. The tray is disposed within a column with the outwardly facing lips of the gasket deformed upwardly against the inside walls of the tower.
In another aspect, the invention includes a method and apparatus for sealing the perimeter of a cartridge tray utilizing a double, pliable seal. The seal material may be supplied as teflon impregnated fiberglass tape, although any pliable material that would be compatible with the process chemicals and temperature conditions within the tower would be suitable. In this sealing method, the fiberglass tape is contained in a channel by a metal retainer band and the edges of the tape extend beyond the edge of the tray to allow the tape to deflect up and out against the tower wall. This arrangement allows the tape seal to conform to irregularities of the tower shell and maintain a seal therein. The arrangement also allows more clearance between the edge of the tray and the tower wall which allows the tray bundle to bypass restrictions and variations in the shell.
In yet another aspect, the invention includes an improved cartridge tray seal for a chemical process tower of the type wherein a cartridge tray is disposed within a tower shell for the passage of vapor and liquid thereacross. The improvement comprises the cartridge tray housing a peripheral sealing section adapted for abutting engagement with the shell, the sealing region including a flaccid member impregnated with material for resisting the liquid and vapor within the process tower. Means are provided for securing the flaccid member about the sealing region for permitting said sealing member to extend outwardly therefrom into engagement with the shell wall. In one embodiment of the invention, the flaccid material is teflon impregnated fiberglass.
In a further aspect, the above described invention includes the sealing region being formed with a generally u-shaped channel adapted for receiving the flaooid material therein. Fastener means are provided for positioning upon the flaccid material and within the channel for the secured engagement of the flaccid material. The securing means may comprise a metallic strap positioned within the u-shaped channel and secured therein against the flaccid material. The flaccid material is provided in a width sufficient to permit its placement within the sealing region with a two sided folded portion extending outwardly therefrom for forming a double lip seal against the shell wall.
In yet a further aspect, the invention includes a method of sealing a cartridge tray within the shell of a chemical process tower comprising steps of providing a flaooid member for positioning within the sealing region of said cartridge tray and impregnating the flaccid member with a material for resisting the chemical effects of the liquid and vapor of the chemical process tower. The flaccid material is secured within the sealing region of the cartridge tray, and the flaccid material is extended outwardly from the sealing region into engagement with the side walls of the shell for the sealed engagement of the tray thereagainst.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further objects and advantages thereof, reference may now be had to the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a cut-away perspective view of a chemical process tower illustrating the various tower internal configurations thereof;
FIG. 2 is an enlarged, side elevational view of the array of chemical process tower cartridge trays of FIG. 1 illustrating the use of sealing members therearound;
FIG. 3 is an enlarged, side elevational, fragmentary, cross-sectional view of a portion of a prior art cartridge tray and sealing member; and
FIG. 4 is an enlarged, side elevational, fragmentary, cross-sectional view of a portion of the cartridge tray and sealing member of FIG. 2.
DETAILED DESCRIPTION
Referring first to FIG. 1, there is shown a fragmentary, perspective view of an illustrative packed exchange tower or column with various sections out away for showing a variety of tower internals and the utilization of one embodiment of the improved high capacity tray assembly of the present invention. The exchange column 10 of FIG. 1 comprises a cylindrical tower 12 having a plurality of packing bed layers 14 and trays disposed therein. A plurality of manways 16 are likewise constructed for facilitating access to the internal region of the tower 12. Also provided are side stream draw off line 20, liquid side feed line 18, and side stream vapor feed line or reboiler return line 32. A reflux return line 34 is provided atop the tower 10.
In operation, liquid 13 is fed into the tower 10 through reflux return line 34 and side stream feed input feed line 18. The liquid 13 flows downwardly through the tower and ultimately leaves the tower either at side stream draw off 20, or at bottom stream draw off line 30. In its downward flow, the liquid 13 is depleted of some material which evaporates from it as it passes through the trays and packing beds, and is enriched or added to by material which condenses into it out of the vapor stream.
Still referring to FIG. 1, the exchange column 10 is diagrammatically arranged for purposes of clarity. In this illustration, the column 10 includes a vapor outlet in overhead line 26 disposed atop the tower 12 and a lower skirt 28 disposed in the lower region of the tower around bottom stream takeoff line 30 coupled to a reboiler (not shown). Reboiler return conduit 32 is shown disposed above the skirt 28 for recycling vapor therein upwardly through the trays and/or packing layers 14. Reflux from condensers is provided in the upper tower region 23 through entry conduit 34 wherein reflux is distributed throughout a liquid distributor 36 across upper packing bed 38. It may be seen that the upper packing bed 38 is of the structured packing variety. The regions of the exchange column 10 beneath the upper packing bed 38 are shown for the purpose of illustration and include a liquid collector 40 disposed beneath a support grid 41 in support of the upper structured packing 38. A liquid distributor 42, adapted for redistributing liquid 13, is likewise disposed therebeneath. A second liquid distributor array 43 is illustrated below the lowest tray 48A. This particular distributor array may be of the type shown in U.S. Pat. No. 4,909,967, assigned to the assignee of the present invention. Likewise, a lower structured packing bed 44 is shown in the lower tower region.
Referring still to FIG. 1, an array of trays is also shown for purposes of illustration within column 10. In many instances, process columns contain only packing, only trays, or combinations of packing and trays. The present illustration is, however, a combination for purposes of discussion of the overall tower and its operation. A trayed column usually contains a plurality of trays 48 of the type shown herein. In many instances, the trays 48 are valve or sieve trays. Such trays comprise plates which are perforated or slotted in construction. The vapor and the liquid engage at or along the tray and, in some assemblies, are permitted to flow through the same openings in a counter-current flow arrangement. Optimally, the vapor and liquid flows reach a level of stability within the tower 10. With the utilization of downcomers, to be described in more detail below, this stability may be achieved with a relatively low flow rate permitting the ascending vapor to mix with the descending liquid. In some embodiments no downcomers are used and the vapor and the liquid use the same openings, alternating as the respective pressures change.
In the present embodiment, each tray is sealed against the tower wall by a special sealing gasket 49, which will be discussed in detail below. The gasket 49 permits the tray 48 to seal against the tower walls 12 in order to facilitate the counter-current flow conditions existing between the ascending vapor 15 and the descending vapor 13. This flow condition is the subject of a myriad of critical design considerations including the position downcomers 54, liquid/vapor ratios, liquid cooling, liquid flow/back-mixing, foaming (froth), height, froth uniformity and the presence of solids or slurries therein. Reliability and corrosion are likewise considerations in the selection of the various elements in the packed towers. The parameters for material selection in the fabrication of the tower internal are in many instances, the result of such considerations. The anatomy of the packed column, as shown in FIG. 1, is likewise described in more detail in an article by Gilbert Chem, one of the inventors herein, entitled "Packed Column Internals" appearing in the Mar. 5, 1984 edition of Chemical Engineering. inoorporated herein by reference.
Referring now to FIG. 3, there is shown an enlarged, side elevational, cross-sectional view of a section of a prior art tray disposed within a chemical process tower and rigidly mounted therein. The tray 50 comprises a plurality of tray members 52 disposed between the downcomers 54 shown in FIG. 1. Liquid 13 is shown to flow across each tray during its descending path through the tray array 50. In this particular embodiment, the tray 52 is mounted to the side wall of the tower by a mounting ring 55. The mounting ring 55 includes a box shaped gland member 56 that is circumferentially disposed around the tray in sealed engagement with the tower walls. Such a seal provides a much larger surface area against which vapor or liquid may be sealed. As ascending vapor mixes with the descending liquid, both vapor and liquid are hopefully prevented from bypassing central tray active area by virtue of such sealing members. However, the box shaped gland member 56 does not provide sufficient flexibility to accommodate out-of-round and deformed sections of the tower shell 12A.
Referring now to FIG. 4, there is shown an enlarged, side elevational, cross-sectional view of the improved sealing gland 60 of the present invention illustrating the mounting of a tray 62 within a process tower 12. The sealing gland comprises a double, pliable seal. The seal material may be supplied as teflon impregnated fiberglass tape 60, although any pliable material that would be compatible with the process chemicals and temperature conditions within the tower would be suitable. In this sealing method the fiberglass tape 60 is contained in a channel 63 by a metal retainer band 64. Channel 63 is secured beneath the tray 62 along the perimeter thereof. The edges 65 and 66 of the tape 60 extend beyond the edge of the tray to allow the tape 60 to deflect up and out against the tower wall 12A. This arrangement allows the tape edges 65 and 66 to conform to irregularities of the tower shell 12A and maintain a seal thereagainst. It is for this reason that flacoid material is utilized in a width sufficient to provide edges 65 and 66 to engage all deformed and out-of-round regions of the shell 12A. The arrangement also allows more clearance between the edge of the tray and the tower wall 12A which allows the tray bundle 62 to bypass restrictions and variations in the shell. It is of distinct advantage to provide more clearance between the tray and the tower walls afforded by the present invention in view of the costs associated within installation problems.
Referring now to FIG. 2, there is shown an array of trays 101 installed in a tower shell 103. Upper tray 104 is disposed atop and above intermediate tray 106 which is disposed above lower tray 108. The tray alignment, configuration and the diagrammatioal representation thereof is shown for purposes of illustration only. A myriad of tray designs and configurations may be incorporated in accordance with the principles of the present invention. What is shown are representative trays in conjunction with a sealing gland assembly constructed in accordance with the principles of the present invention and as particularly described relative to FIG. 4. A sealing gland assembly 110 is shown disposed along the perimeter of each of the trays 104, 106 and 108, which assembly provides a means for sealing said cartridge tray against the passage of vapor and liquid thereover and therethrough. In some instances, liquid is disposed above the sealing member, as in the region of a downcomer. For example, upper tray 104 is constructed with a reservoir 112 disposed adjacent liquid input pipe 114. The liquid 116 is allowed to accumulate within the vessel 112 above the sealing member 110 for flowing across the surface of the tray 104. A downcomer 118 is shown on the opposite side of tray 104, which downcomer permits the flow of liquid 116 downwardly toward tray 106. In a lower region of downcomer 118 the liquid 116 is accumulated for discharge in an open region 120 beneath the downcomer 118 wherein liquid is discharged outwardly therefrom for flow across tray 106. A downcomer 122 is likewise disposed on the opposite side of tray 106 for discharging liquid downward to lower tray 108. Finally, a downcomer 124 is shown disposed on the side of tray 108 opposite downcomer 122.
The process column illustrated in FIG. 2 and described above, is shown for purposes of illustration. Each of the cartridge tray sealing members 110 are disposed in a region of the vessel shell 103 that is subject to deformation. As discussed above, the deformation may occur through the initial assembly process wherein welding causes distortion in the generally cylindrical side walls and/or in the process of physical loading. For example, the height of liquid 116 in top tray 104 can cause deformation both in the tray 104 as well as in related structural members. The sealing member 110 must be capable of accommodating surface irregularities between the tray 104 and the shell 103. For this reason, each illustration of the sealing member 110 includes a pair of lip members 130 and 13 disposed outwardly against the shell 103 from tray channel 132. As described above, the channel 132 is secured to the underside of the cartridge tray for housing the teflon impregnated material therein and for the outward extension therefrom to facilitate the sealing as described herein. The sealing also prevents the upward flow of vapor 140 from passing around the trays along the sidewalls of the shell 103. Such passage would bypass the active area of the trays and reduce the efficiency of the column.
Shrinkage of the tower walls may occur through welding as well as physical loading therein. Deformation in the shell can also occur when welding the nozzle to the shell surface, which nozzles are necessary for the function of the tower as shown in FIG. 2. Deformation may occur at the long seam of the tower which is a structural concern in both the fabrication as well as the use of cylindrical towers. As shown herein, the loading of the trays within the tower with the counter current flow of vapor and liquid will impart to the shell both a station and a dynamic load which must be accommodated with appropriate flexibility in the sealing members thereagainst. Since it is well known that welding has a drastic effect upon the metal shell itself and the diameter which may be reduced due to shrinkage at welded circumferntial shell joints, it is necessary for sealing members to have flexibility and accommodation of spaces. It is for this reason that the double contact, pliable cartridge tray edge seal of the present invention provides such a marked advance over prior art configurations. The surface irregularities of the tower shell maybe easily accommodated with the pliable cartridge and the sealing effectiveness enhanced by the double contact afforded therewith.
In operation, the sealing gland of the present invention affords the tray the flexibility of accommodating irregularities in both the tray and the wall of the chemical process column. It is well known that such process column walls are not perfectly cylindrical and various surface irregularities can cause sealing problems with conventional prior art sealing glands. The use of rigid wipers and the like, though successful in accommodating various irregularities, provides a fixed dimensional shape that may often not accommodate said irregularities. The present invention facilitates surface irregularities by utilizing a substantially flaccid member that is sufficiently impregnated with a substance, such as teflon, whereby substantial amounts of both vapor and liquid are prevented from passing therethrough when installed as shown herein. The structural ring of the tray in which the teflon impregnated fabric is mounted provides the overall shape that accommodates the tray-tower installation. In this manner, manufacturers may also reduce the time and expense necessary for precision fabrication of tower internals which are mandated by the requirements for sealing between the trays and the tower walls.
In addition to the initial installation feasibility, the teflon impregnated fabric further provides enhanced reliability by presenting a surface capable of withstanding the hostile chemical environment typically found in such tray installations.
It is thus believed that the operation and construction of the present invention will be apparent from the foregoing description. While the method and apparatus shown or described has been characterized as being preferred, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the following claims. | A cartridge tray seal for a chemical process tower. The seal includes a teflon impregnated fiberglass member which presents a generally flaccid sealing element. The member is folded within a generally u-shaped channel positioned around the perimeter of the cartridge tray. A securing strap is positioned within the u-shaped channel to sandwich the fiberglass material therein in a configuration for presenting a pair of outwardly extending sealing lips for engagement against the shell wall. This double pliable seal is able to accommodate shell wall deformations and out-of-round conditions which would ordinarily result in liquid and/or vapor leakage around the cartridge tray. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to the field of methods and processes for extraction of liquids or juices of materials to be pressed and for control of presses, including membrane presses, particularly to an automatic determination process for command and control of a preliminary pressurized or forced draining before pressing in batch presses.
FIELD OF THE INVENTION
Currently, the pressing of destemmed grape crops or of materials to be pressed that contain a great deal of free-run juices generally poses many problems, at the beginning of the pressing cycle, for the users of batch presses (membrane presses, plate presses, . . . ). "Free-run juices" are those juices which flow from the material to be pressed by virtue of the inherent pressing of the material upon itself or juices which flow because of the inherent qualities or characteristics of the material to be pressed. These are juices that are already present in the pressing tank prior to any pressure being exerted upon the material to be pressed by a pressing element of the press.
Among the most frequently encountered problems can be mentioned on the one hand, squirtings of juices, and on the other hand, blockages of juices, involving dangers of clogging of the draining elements, such as the orifices permitting the evacuation of liquids outside the tanks of the press.
These malfunctions, for the user, are reflected by considerable losses of time, by a necessity of monitoring the press and by difficulties in defining an automatic pressing cycle (a cycle that is variable as a function of the filling conditions).
These problems and malfunctions are due to the presence of large quantities of free-run juices in the press after it is filled, the evacuation of these juices being poorly controlled by the known automatic pressing processes.
The study of said harmful phenomena makes it possible to distinguish two main causes of malfunction of the presses when the pressed grape crop contains a great deal of free-run juices.
Actually, at the beginning of the pressing cycle, the air located between the mobile pressing element and the grape crop is trapped since it cannot pass through the liquids blocked in the press, or the mass of the materials to be pressed.
In addition, the pressure generated in the tank of the press by the displacement of the pressing element (membrane, for example) is transmitted, by the liquids, to the materials in contact with the orifices assuring the evacuation of the liquids or juices outside the press and thus causes the clogging of the latter.
SUMMARY OF THE INVENTION
The object of the present invention is to eliminate such drawbacks and disadvantages by preparing the materials to be pressed for a normal pressing cycle, such as, for example, the cycle described in French patent application No. 90-14488 filed on Nov. 16, 1990 in the name of the same applicant.
For this purpose, this invention has as its object an automatic determination process for command and control of a forced or preliminary pressurized draining before pressing for batch presses, characterized in that it consists, after filling of the press and before starting the normal pressing cycle, in measuring continuously the flow rate of the liquids without applying pressing pressure, in ascertaining the minimum value and maximum value of said flow rate, in particular when the tank of the press rotates, in then comparing these values respectively with predetermined quantities, then, as a function of the results of said comparisons, in performing, if necessary, a forced draining of the materials to be pressed, while simultaneously checking for the possible presence of a clogging of the orifices for evacuation of liquids, in repeating the preceding operations until the results of said comparisons no longer entail the performing of a forced draining and, finally, in starting the normal pressing cycle.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be better understood as a result of the following description, which relates to a preferred embodiment, given by way of nonlimiting example, and explained with reference to the accompanying diagrammatic drawings, in which:
FIGS. 1A, 1B, 1C and 1D illustrate, by section views of a membrane press, the various phases of a forced draining according to the invention, and,
FIG. 2 represents, on the same timing diagram, the curves of variation of the flow rate of the liquids and of the pressing pressure applied during a forced draining according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
According to the invention, and as may be seen in FIGS. 1 and 2, the automatic determination process for command and control of a forced draining consists, after filling of press 1 and before starting normal pressing cycle C, in measuring continuously the flow rate D of the liquids without applying pressing pressure, in ascertaining the minimum value D min and the maximum value D max of said rate D, in particular when the tank of press 1 rotates, in then comparing these values D min and D max respectively with predetermined quantities K 1 ×D o and K 2 ×D o , then, as a function of the results of said comparisons, in performing, if necessary, a forced draining of materials to be pressed 2, by simultaneously checking for the presence of a clogging of orifices 3 for evacuation of said liquids, in repeating the preceding operations until the results of said comparisons no longer entail the performing of a forced draining and, finally, in starting the normal pressing cycle C.
The latter can consist of one of the numerous pressing cycles known to a person skilled in the art, and, advantageously, of the one described in said French patent application No. 90-14488.
According to a first characteristic of the invention, a forced draining of materials to be pressed is performed only when at least one of the following conditions is verified:
D.sub.max ≧K.sub.1 ×D.sub.o or D.sub.min ≧K.sub.2 ×D.sub.o,
where K 1 is a constant whose value is between 0.5 and 2, where K 2 is a constant whose value is between 0.05 and 0.4 and where D o is a flow rate value determined as a function of the size and the filling rate of the tank of press 1.
Of course, it is understood that if none of the above two conditions is verified, a normal pressing cycle C is immediately initiated.
For a membrane press, D o can advantageously be determined automatically as indicated in the above-mentioned patent application in the name of the applicant.
In regard to constants K 1 and K 2 , they can preferably be equal respectively to 1 and 0.15.
As FIGS. 1A, 1B, 1C and 1D of the accompanying drawings show, by way of example relative to a membrane press, the forced draining of materials to be pressed 2 consists in causing, first of all, the removal of air 4 contained in the tank of the press 1, then in performing a controlled pressing at low pressure, followed by a decompression of said tank.
To be able to drive air 4 trapped between membrane 5, on the one hand, and materials to be pressed 2 and the free-run liquids or juices, on the other hand, the tank of press 1 is brought into a position that allows the removal of air 4 through a suitable opening, for example one of the drains 3' used to evacuate the liquids during the pressing phase (FIG. 1B).
Then, the pressing element, in this case membrane 5 (FIG. 1C), is displaced so as to raise materials to be pressed 2 in the tank in the direction of said drain 3', until all of the air is driven from this tank.
Consequently, air 4 contained in the tank of press 1 is driven outside tank 1 through orifices 3 and at least a drain 3' provided for the evacuation of liquids, the tank 1 being positioned so that the orifices 3 and the drain 3' are located in the upper part of the tank and air 4 then being driven by the raising of materials to be pressed 2 in the tank under the action of the pressing element.
This operation can, in the case of a membrane press 1, be perfectly controlled by controlling the pressure applied to said membrane 5, which is a function of the diameter of the tank of said press 1.
As soon as air 4 is completely driven from the tank of press 1, the latter is again placed in normal pressing position, corresponding to a maximum ability to evaluate the liquids or juices extracted and, a controlled pressing at low pressure is started.
This controlled pressing at low pressure for the forced draining consists, after removal of air 4 contained in the tank of press 1, in applying a first pressing pressure P 1 of low value, for a time T 1 determined as a function of the flow of the liquids, then in applying, if no clogging of orifices 3 for evacuation of the liquids has been detected during pressure level P 1 , a second pressing pressure P 2 , of greater intensity than P 1 and, then, in performing a decompression and, optionally, a mixing of materials to be pressed 2 after completion of pressure level P 2 .
Pressures P 1 and P 2 can, by way of indication, have values respectively between 0.1 and 0.2 bar and between 0.2 and 0.5 bar.
Time T 1 can be calculated, during pressure level P 1 , by analyzing the decrease in the flow rate of the liquids or juices extracted as described in the above-mentioned patent application in the name of the same applicant.
According to a characteristic of the invention, pressure level P 2 is maintained for at least a predetermined time T 2 and, if necessary, beyond the latter until flow rate D of the extracted liquids falls below a set-point value D 2 , a function of D o .
For a membrane press, the value of time T 2 can, advantageously, be between 1 minute and 5 minutes, while preferably being on the order of 2 minutes and the set-point value D 2 can be between 2×D o and 5×D o , while preferably being on the order of 3×D o .
The decompression after forced draining is accompanied by a mixing of materials to be pressed 2, in the form, for example, for a membrane press, of 1 to 5 complete rotations of the tank of press 1, and, preferably, of 2 rotations of this type.
It can also happen that excess pressures generated during the filling, by means of a pump for example, of the tank of press 1, may cause a clogging of the orifices that assure, in normal operation, the evacuation of liquids or juices.
Now, according to a feature of the invention, orifices 3 are considered as being clogged when, after application of the first pressure P 1 for a time T C during a forced draining, flow rate D of the extracted liquids is less than D o , this while D min ≧K 2 ×D o during the phase preceding the application of pressure P 1 .
When said conditions are verified, therefore in the case of detection of a clogging, the process according to the invention can consist in prolonging the application of pressure P 1 for a predetermined time T P , then in disengaging clogged orifices 3 by performing a vigorous mixing of materials to be pressed 2 after decompression.
By way of indication, time T C can be on the order of 10 seconds, time T P can be between 1 minute and 5 minutes (preferably 2 minutes) and, the number of rotation revolutions of the tank of press 1, for a membrane press, can be between 2 revolutions and 5 revolutions (preferably 3 revolutions).
During this decompression phase, the conditions leading to a forced draining are again controlled.
As a result of the invention, it is consequently possible to detect the necessity of a forced draining of the materials to be pressed, before the engaging of a normal pressing cycle C and to automate and control this forced draining.
In addition, the invention also makes it possible to detect the possible clogging of the orifices for evacuation of the clogged liquids and to automate the unclogging of the latter.
Thus, the process according to the invention, by avoiding the complications connected with the presence of large quantities of free-run juices, brings about an optimizing of the yield of press 1 under consideration, particularly for materials to be pressed containing a great deal of free-run juices and after filling of press 1, for example by a closable opening 7 through which materials to be pressed are loaded.
Of course, the invention is not limited to the embodiment described and represented in the accompanying drawings. Modifications are possible, particularly from the viewpoint of the constitution of technical equivalents, without thereby going outside the scope of protection of the invention. | An automatic process in which after the press is filled and before starting a normal pressing cycle the flow rate of liquids is measured continuously without applying any pressing pressure. The tank is then rotated and the minimum and maximum values of the flow rates are determined and then compared respectively with predetermined values. Based upon this comparison and as a function of the results of the comparisons there is performed a preliminary pressurized draining of the materials to be pressed while at the same time the orifices for evacuation of the liquids are checked for possible clogging. These operations are repeated until the results of the comparisons no longer warrant a pressurized preliminary draining and subsequently initiating the normal pressing cycle. | 1 |
BACKGROUND OF THE INVENTION
The present inventions relates to a liquid dispenser and more particularly to a dispenser of liquid pharmaceuticals that are to be delivered by spraying or by jet.
There already exist liquid dispensers of the type comprising in particular a tank fitted with liquid-extractor means such as a valve or a pump having a dispenser head mounted thereon.
The extractor means are suitable for being actuated by moving the tank axially relative to a delivery tube which is fed by the extractor means and which has a portion that projects outside and that is covered by said head.
Nevertheless, for certain pharmaceuticals such as homeopathic or ophthalmic liquids, for example, the doses to be administered correspond to volumes that are very small, of the order of 30 microliters (μl) to 50 μl.
Under such conditions, the liquid is packaged in tanks constituted by small-content flasks which are therefore of small size, thus making them difficult to use.
In particular, the head covering the spray tube is then of small dimensions which are ill-suited to the numerous handling operations which are nevertheless required in order to obtain axial displacement of the delivery tube.
SUMMARY OF THE INVENTION
An object of the present invention is to resolve those technical problems by providing packaging which is easier to handle, and to do so independently of the size of the doses of liquid that are to be dispensed.
According to the invention, this object is achieved by means of a dispenser of the above type characterized in that it comprises firstly a discharge duct connected in leakproof manner to the outer portion of the delivery tube and passing through an endpiece connected rigidly to a housing containing the tank, and secondly at least one side knob engaging the tank or the delivery tube and carrying a cam designed to co-operate in sliding contact with at least one sloping wall secured to said endpiece in such a manner that substantially radial thrust on said knob is transformed into axial displacement of the tube relative to the tank, thereby causing the liquid to be dispensed.
According to an advantageous characteristic, the tank is enclosed in removable manner inside the housing that is defined at its top end by said endpiece.
According to another characteristic, said knob has a pushbutton-forming outside flank whose generator lines are at least in part parallel with those of the duct.
Preferably, said pushbutton-forming outside flank extends in flush manner in openings formed in the side wall of the housing.
Advantageously, said pushbutton-forming outside flank has fluting.
In a variant, said endpiece is extended downwards by a substantially cylindrical skirt provided at its bottom end with fastener members for fastening to the housing.
In another variant, said housing is provided with a set of two diametrically opposite knobs.
Advantageously, the free end of said duct is provided with a spray nozzle.
Preferably, the duct is connected to said tube by mutual engagement with radial clamping.
In a first embodiment, the tank is held stationary inside the housing while said knob is secured to the tube and said sloping wall slopes towards the bottom of the discharge duct.
In which case, said discharge duct is slidably mounted inside the endpiece while the tank is held stationary in a stand fixed in optionally releasable manner to said housing.
Preferably, said knob is provided with a spacer-forming link arm connected to said duct.
Furthermore, said cam is formed by a bulge carried by the inside flanks of the knob.
In a second embodiment, said knob is secured to the tank which is axially movable inside the housing, while said sloping wall slopes towards the top of the discharge duct.
In which case, said discharge duct is fixedly mounted in the endpiece while the tank slides in an internal bore in the housing.
Preferably, said knob is mounted on the neck of the tank by means of a fastening ring.
Advantageously, said cam is formed by the bottom edge of the outside flank of the knob.
In a particular variant, said sloping walls present faces coming into contact with said cams and having varying slope.
The dispenser of the invention is of highly ergonomic shape and provides flexibility and great comfort in use.
A particularly suitable application lies in the field of spraying cosmetics such as hydrating substances or pharmaceuticals such as nasal solutions.
The dispenser can be adapted equally well to a pressurized tank fitted with a valve or to an atmospheric tank fitted with a pre-compression pump.
The pushbutton-forming side knobs provide control over the extractor means that is easy, reliable, and sensitive, thus enabling the liquid to be dispensed with great accuracy.
Furthermore, the overall appearance is very attractive and looks like a conventional bottle or flask type container.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood on reading the following description accompanying by the drawings, in which:
FIGS. 1A and 1B are section views through a first embodiment of a dispenser of the invention shown respectively in a rest position and while dispensing;
FIGS. 2A and 2B are respectively a front view and a perspective view of the embodiment of FIGS. 1A and 1B; and
FIGS. 3A and 3B are section views of a second embodiment of the dispenser of the invention respectively in a rest position and while dispensing.
DETAILED DESCRIPTION OF THE INVENTION
The dispenser shown in the figures is designed to deliver successive doses of a liquid contained in a tank.
As shown in FIGS. 1A, 1 B, 3 A, and 3 B, the dispenser is fitted in conventional manner with liquid extracting device which is constituted either by a precompression pump P mounted in this case on the neck of an atmospheric tank R, or else by a valve (not shown) mounted on a tank under pressure.
The extracting device is suitable for being actuated by the user who, for this purpose, exerts manual thrust on a delivery tube 10 fed by the extracting device and has an end portion that projects outside the tank R, which end portion is optionally covered by a dispenser head (not shown).
The thrust can also be exerted on the bottom of the tank R by the user who then holds the tube 10 stationary, such that in all cases there is axial relative displacement of the tube T towards the tank R with said tank being put under pressure.
When the valve of the pump opens, then the liquid can escape to the outside via the tube T which then returns to its initial position under drive from return means (not shown).
In the invention, the external portion of the delivery tube T is connected in leakproof manner to a discharge duct 1 . The connection is implemented in this case by the tube T being engaged in the duct 1 with radial clamping. Where appropriate, the bottom end 1 a of the duct 1 could be provided with an appropriate countersink.
The discharge duct 1 extends the tube T axially through an endpiece 2 .
The endpiece 2 is also connected rigidly to a housing B that contains the tank R by means that are described below.
In the embodiments of the figures, the tank R is enclosed inside a housing B whose top portion is defined by the endpiece 2 and whose bottom portion is defined by a bottom-forming stand 3 . The housing B is optionally removable so as to enable the housing to be refilled or to enable said tank to be refilled.
In FIGS. 1A and 13, the endpiece 2 is extended downwards by a skirt 2 a that is substantially cylindrical and provided at its bottom end with fastening members 23 designed to co-operate with complementary members 32 provided on the stand 3 so as to connect the endpiece 2 rigidly to the housing B.
The skirt 2 a of the endpiece 2 constitutes a portion of the side wall of the housing B and it can be made (FIG. 2B) integrally with the endpiece 2 , or else it can be made in the form of a separate piece for assembly thereto (FIG. 2 A).
The top end 1 b of the duct 1 is provided with a spray nozzle 10 .
The dispenser of the invention has at least one, and in this case two diametrically opposite knobs 11 and 12 .
Each of the knobs 11 , 12 is provided with a cam 110 , 120 for co-operating in sliding contact with a sloping wall 21 , 22 secured to the endpiece 2 . These knobs engage either with the delivery tube T as in the embodiment of FIGS. 1A and 1B, or else with the tank R as in the embodiment of FIGS. 3A and 3B.
The length of the sloping walls 21 , 22 is adjusted as a function of the stroke needed by the tube T to enable a predetermined dose of liquid to be delivered. The position of the housing B and of the endpiece 2 relative to the tank R or the tube T is maintained by appropriate fastening means providing a rigid connection that suffices to guarantee that the liquid is extracted in accurate doses.
Co-operation between the cams 110 , 120 of the knobs 11 , 12 and the sloping walls 21 , 22 of the endpiece is such that substantially radial thrust on at least one of the knobs causes upward or downward sliding which in turn causes the tube T to move axially closer to the tank R. The relative stroke of the tube T corresponds to actuating the extracting device P in such a manner as to deliver one dose of liquid.
Openings 20 are formed in the side wall of the housing B to receive the knobs 11 , 12 with a small amount of clearance relative to their outside flanks 11 c, 12 c.
The outside flanks 11 c, 12 c extend in the openings 20 so as to be flush with the surrounding wall of the skirt 2 a so as to avoid creating a discontinuity on the housing and so as to conserve its shape as a body of revolution. The edges of the openings 20 are advantageously chamfered.
The outside flanks 11 c, 12 c form pushbuttons and possess generator lines which are parallel at least in part to those of the duct 1 .
The visible faces of the flanks 11 c, 12 c are preferably provided with fluting 13 to improve manual thrust and avoid any slipping.
In FIGS. 1A and 1B, the cams 110 , 120 are made in the form of projections carried by the top portions of the inside flanks 11 b, 12 b of the knobs 11 , 12 and the sloping walls 21 , 22 slope towards the bottom of the duct 1 .
Under such circumstances, the cams are in sliding contact with the bottom faces of the sloping walls.
The knobs 11 , 12 are attached to the duct 1 by link arms 11 a, 12 a that form spacers and that extend substantially perpendicularly to the side wall of said duct.
Where appropriate, the link arms are integrated in a disk which is mounted coaxially about the duct 1 .
The inside flanks 11 b, 12 b extend the arms 11 a, 12 a upwards and radially away from the duct 1 , thereby connecting them with the outside flanks 11 c, 12 c.
The inside flanks 11 b, 12 b are provided with stiffeners in the form of ribs 111 , 112 which nevertheless allow a certain amount of flexibility in deformation to remain.
The duct 1 slides freely in an axial bore formed in the solid endpiece 2 whereas the tank R is held stationary inside the housing B.
The top end 1 b of the duct 1 projects freely out from the endpiece 2 , at least when the dispenser is in the rest position.
The stand 3 has a cylindrical cavity 30 for receiving the tank R and of dimensions that are adjusted for this purpose so as to hold the tank by radial clamping.
To facilitate insertion of the tank R in the stand 3 , the cavity 30 is provided with a tapering top mouth 31 .
In FIGS. 3A and 3B, the knobs 11 , 12 are secured to the tank R which in this case is axially movable inside the housing B while the discharge duct 1 is mounted to be fixed in the endpiece 2 and projects downwards therefrom.
The tank R slides axially in guided manner in an internal bore 32 formed in the stand 3 , while the inside flanks 11 b, 12 b are subjected to bending towards the axis of the duct 10 under the effect of the radial thrust on the knobs 11 , 12 whose outside flanks 11 c, 12 c then come to be received inside the endpiece 2 .
The sloping walls 21 , 22 slope up towards the top of the duct 1 and co-operate, still by sliding, with the bottom edges of the outside flanks 11 c, 12 c forming the cams of the knobs 11 , 12 .
To this end, the bottom edges of the flanks 11 c, 12 c are curvilinear in profile, and under such circumstances it is the top faces of the sloping walls 21 , 22 that come into sliding contact with the cams.
Each of the sloping walls 21 , 22 is made as a plane portion carried by a cone placed between the inner side wall of the housing B and the endpiece 2 and being secured, where appropriate, to the bottom portion of said endpiece.
The contact faces of the sloping walls 21 , 22 are optionally of slope that varies along the height thereof in a manner that is discontinuous or continuous (i.e. defining a curve) thus making it possible, for example, for the slope to be shallower in the lower portions thereof corresponding to the beginning of thrust being applied to the knobs 11 , 12 .
The knobs 11 , 12 are mounted on the neck of the tank R by means of a ring 121 secured to the inside flanks 11 b, 12 b and secured to the inside flanks 11 b, 12 b and fitted, for example, with snap-fastening members for co-operating with complementary members carried by the neck of the tank R or by a bushing D that also serves to lock the extracting device P. | A liquid dispenser of the type comprising a tank (R) fitted with liquid extractor means (P) suitable for being actuated by axial displacement of the tank relative to a delivery tube (T) having a portion that projects outwards, the dispenser being characterized in that it comprises firstly a discharge duct ( 1 ) connected in leakproof manner to the outer portion of the delivery tube (T) and passing through an endpiece ( 2 ) connected rigidly to a housing (B) containing the tank (R), and secondly at least one side knob ( 11, 12 ) engaging the tank or the delivery tube and carrying a cam ( 110, 120 ) designed to co-operate in sliding contact with at least one sloping wall ( 21, 22 ) secured to said endpiece ( 2 ) in such a manner that substantially radial thrust on said knob ( 11, 12 ) is transformed into axial displacement of the tube (T) relative to the tank (R), thereby causing the liquid to be dispensed. | 1 |
BACKGROUND OF THE INVENTION
The personal computer has enjoyed more and more frequent and versatile application in commercial and private areas in communications technology, particularly in telecommunications. A comfortable user surface enables an uncomplicated operation and utilization of the personal computer. In telecommunications, the personal computer can be coupled, for example, to a subscriber terminal equipment (telephone, switching system). The services (for example telephone number register, computer-assisted dialing, telephone manager) that are possible in telecommunications technology can be designed more transparent and user-friendly for the telecommunication subscriber on the basis of this combination. The combination of personal computer/subscriber terminal equipment makes it possible for the telecommunication subscriber to select the call numbers of another telecommunication subscriber stored in the personal computer from a telephone number register and to initiate a call set-up with the personal computer. It is of particular help in the selection of a telecommunication subscriber when telephone numbers from an electronic telephone book can be selected at the personal computer and connections can be set up to other telecommunication subscribers.
The invention is directed to a circuit arrangement for data conversion in a data transmission between a serial data interface of a personal computer and a serial data interface of a communication equipment.
Given a combination of a personal computer with a subscriber terminal equipment such as, for example, a switching system or an added-feature telephone having a plurality of function keys, additional transmission paths are required within the device combination. Communication is required due to the collaboration of the personal computer with the communication equipment. This requires a continuous occupation of a V.24 data interface at the personal computer.
Up to now, it was standard to employ a specific modem (Hayes modem) given a telephone number selection implemented with the personal computer. These modems are thereby installed, for example, at an interchange point between a public communication network and private lines. A further possibility of arranging a Hayes modem in system-oriented fashion given the combination of personal computer and subscriber terminal equipment is that the Hayes modem is integrated on a PC card and is inserted in the personal computer at a free card slot. A specific PC card, for example a plug-in modem having a connected telephone, assumes the function of the Hayes modem. The occupation of a PC card slot and/or the occupation of at least one defined data interface considerably limits the possible use of the personal computer. In favor, for example, of a telecommunications-oriented use of the personal computer, the integration of circuits for system expansion that are implementable on pluggable PC cards must thus be foregone.
SUMMARY OF THE INVENTION
It is an object of the invention to disclose a way, given optimally low hardware and/or software load on a personal computer, to enable a selection of telecommunications subscribers and the control of communication procedures proceeding from a personal computer connected to the telecommunications equipment.
This object is achieved in accordance with the invention by providing a circuit arrangement for data conversion in a data transmission between a serial data interface of a personal computer and a serial data interface of the communication equipment. A microprocessor module is arranged between a level-converting module and a decoupling module, the microprocessor module comprising a serial-to-parallel converter arranged at an input side thereof, a parallel-to-serial converter arranged at an output side thereof, and a control means for converting data according to a given procedure. The level-converting module has its input side connected to the serial data interface of the personal computer and its output side connected to the serial-to-parallel converter. The decoupling module which is provided has means for electrical isolation of the communication equipment from the personal computer, and has its output side connected to the serial data interface of the communication equipment and its input side connected to the parallel-to-serial converter.
The invention is distinguished by the advantage that a selection of a telecommunication subscriber as well as communication procedures between a personal computer and a subscriber terminal equipment are possible without auxiliary hardware equipment. A PC slot is not occupied. A limitation in the expansion of the personal computer (for example, graphics card, memory card . . . ) or an abandonment of periphery equipment due to a permanently occupied PC slot or a special data interface is not necessary. Beyond this, it is especially advantageous to achieve cross-system procedures such as, for example, the control or interrogation of function keys of a subscriber terminal equipment connected to a personal computer. The data transmission between the personal computer and the communication equipment thereby advantageously occurs only over a serial data interface at the personal computer. Furthermore, the afore-mentioned performance features are not blocked by the outage of the personal computer given a malfunction in the operating system of the personal computer. An uncomplicated unplugging of a plug-type connection at the data interface at the malfunctioning personal computer and a new connection of the plug-type connection to a data interface at an operational personal computer enables an immediate re-employment of the described performance features.
A further development of the invention is that the input of the microprocessor module can be input with Hayes command input data. The microprocessor module converts the data into a pulse sequence adapted to the telecommunications equipment so that a connection to other subscriber terminal equipment or data processing systems is achieved via a telecommunications equipment connected to a switching system.
A development of the invention is that the microprocessor module can be switched into a transparent condition by an instruction mode, this yielding the advantage that a broader signaling than the known Hayes command is possible between the telecommunications equipment and the connected personal computer. A control of more complex procedures including status requests of supplementary performance features thereby becomes possible. This yields the advantage that an expanded user surface for the subscriber terminal equipment is achieved given an appropriate selection. Beyond this, function requests are possible in the subscriber terminal equipment. This yields the advantages that, for example, a constant function and status check can be implemented via performance features that are integrated in the subscriber terminal equipment.
In a further development of the invention, the components employed in the decoupling module for the electrical isolation of the personal computer and the communication equipment can be opto-couplers. This yields the advantage that a potential difference with respect to ground potential does not lead to the destruction of electronic circuits in the personal computer or in the communication equipment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block circuit diagram of a circuit arrangement according to the invention;
FIG. 2 is a flow chart of a program "Start V.24";
FIG. 3 is a flow chart of a program "Transparent"; and
FIG. 4 is a flow chart of a program "Start Device".
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 schematically illustrates, in a scope necessary for an understanding of the invention, a circuit arrangement for data conversion in an asynchronous, bidirectional data transmission. The circuit arrangement is essentially formed by a level-converting module TR, a microprocessor module MP, a decoupler module EM, and a power supply module SV.
The input ETR of the level-converting module TR is connected to a serial data interface COMP (COM-Port) of the personal computer PC. Given a selection of a communication subscriber via the keyboard of the personal computer PC, this selection is input with the corresponding Hayes command. The signal level of the coded data present at the input side at the level-matching module TR corresponds to a V.24 signal level. Receiver modules are utilized in the level-matching module TR that convert the V.24 level into the TTL level and the TTL level into the V.24 level. For example, components Max 234 of the MAXIM Company can be employed for this purpose.
The signal level of the coded data is matched at the output ATR of the level-matching module TR to the voltage level needed in the microprocessor MP. Two receiver/transmitter modules UART1, UART2 for the serial-to-parallel and parallel-to-serial conversion of data streams as well as a control unit μP for processing data words are arranged in the microprocessor module MP. A single-chip processor, for example the 80C51 of INTEL, or the 80C31 having an additional EPROM, for example the 27C256, can be utilized as the control unit μP. The serial data present at the input EMP of the microprocessor module MP are converted into parallel data word formats by the first UART1 module. An autonomous module such as, for example, the UART SCC2691 of VALVO, is employed as UART1 for connection to the PC. The control unit μP interprets the data present in data words. Corresponding to the expansion or to a product line of the communication equipment T (for example HICOM, SET 451, 551, 751), the control unit μP of the microprocessor module MP converts the data transmitted from the personal computer PC, for example the Hayes commands, into pulse sequences. These pulse sequences correspond to the pulse sequences that are initialized by the actuation of function keys, for example the selection key or memory keys at the communication equipment T (see FIGS. 2, 3, 4).
The data transmitted from the personal computer PC are then respectively further-processed in the subscriber terminal equipment T as though they had arisen by direct actuation of the function keys.
The decoded and matched data that are present in parallel are converted into a serial data stream by a second receiver/transmitter UART2.
The control signals present at the output of the microprocessor module MP are forwarded to the subscriber terminal equipment T and the serial data interface EZ therein via a decoupling module EM. The serial data interface E2, as an expansion location, is normally provided for the connection of auxiliary equipment. The E2 data interface is constructed for the communication between a plurality of processors 80C51 of INTEL. The method is based on a 9-bit transmission, whereby one bit serves the purpose of distinguishing between address and data information. In a further development, the circuit of the second receiver/transmitter UART2 can be integrated in the 80C51 control unit μP. The data lines between the input EEM and the output AEM of the decoupling module EM are electrically isolated by opto-electrical components, for example opto-couplers. The electrical isolation between personal computer PC and subscriber terminal equipment T would likewise be possible in the level-converting module TR. Dependent on whether the electrical isolation occurs at the data interface side E2 of the subscriber terminal equipment T or following the V.24 interface of the personal computer PC, the 5 volt supply or only the supply of the level-converting modules is electrically isolated from the line feed. For example, opto-couplers having the type designation HCPL 2200 are utilized for the electrical isolation of the electrical signals. The level-converting module, microprocessor module, and the decoupling module are each respectively connected to the power supply module SV by lines STR, SVA; SMP, SVA; SEM, SVA. The power supply module SV is connected to the communication equipment T via a further connection SK. The power supply module SV is connected to the operating voltage deriving from a telephone line via this connection SK. Corresponding to the connected modules, the power supply module SV transforms the operating voltage into the respectively required operating voltage in the connected modules. The power supply module SV is composed of a DC/DC converter that generates 5 V for supplying the electrical components from the telephone line voltage. Discrete components or an integrated component such as, for example, the component PSB2120P of Siemens AG, can be utilized as the DC/DC converter.
FIG. 2 schematically shows a flow chart of a program "Start V.24". With this program, data are read out, from, example, a memory unit of a personal computer PC, via a data interface COMP and are forwarded to a microprocessor module MP. The data are evaluated in the microprocessor module MP, and a serial-to-parallel converter UART1 is set. The program "Start V.24" implemented in the microprocessor module MP interrogates the data stream coming from the data interface COMP of the personal computer PC until, for example, the data word "A" is present at the input of the microprocessor module MP. After evaluation of the data word, the program execution leads to a following branch. When, for example, a "T" follows as a next data word, then a transmission rate (for example, 300 to 9600 bit/s), a data word length (for example 8 bits) as well as a parity method are recognized from the received data word sequence "AT", and the UART is correspondingly set. When a different data word input follows after the input of the received data word "A", the program returns to its starting address. The procedure of the data word input occurs until the data word sequence "AT" arises. After all data which set the serial-to-parallel converter UART1 are received and have been terminated by an end of line mark [CR], the function of the microprocessor module MP is respectively defined in greater detail by further data words. Following data word sequences are received and interpreted by the microprocessor module MP. In detail, these are the following data word sequences that effect a branching of the program "START V.24":
Input of the end of line mark [CR]:
Whether the communication between the personal computer PC and the microprocessor module MP is functioning can be identified with this dummy command.
Input of the data word sequence d 123 [CR]:
Given input of the data word 1 (selection digit 1), a further data word that emulates the beginning of a key pressure on the "push button 1", and a second data word that emulates the end of the key pressure, are deposited in a queue of a memory unit of the microprocessor MP. The same storing event occurs for the "selection digit 2" and the "selection digit 3".
Input of a data word sequence h [CR]:
A call cleardown occurs after the input of this data word sequence. A data word that initially emulates the end of the key pressure of a disconnect button is thereby entered into the queue of the memory unit of the microprocessor module MP.
Input of a data word sequence z [CR]:
A resetting of the microprocessor module MP occurs after the input of this data word sequence.
Input of a data word sequence % u1 [CR]:
The request to forward the characteristics of the type of the telecommunication equipment T connected to an E2 data interface to the PC occurs after input of the data word sequence.
Following the above-recited data sequences, a transmission of the data word sequence "OK" (command accepted) via the data interface COMP to the personal computer PC occurs as controlled by the control unit of the microprocessor module MP. Following thereupon, the execution routine of the program "START V.24" again begins at its starting address.
Input of a data word sequence % u [CR]:
After input of this data word sequence, the microprocessor module is switched into a transparent mode. After the transmission of the character sequence "OK", the program "START V.24" branches into a program "Transparent" that executes the transparent mode.
When an undefined input of a data word sequence occurs, then the user is alerted by an error display "ERROR", for example at a data viewing means of the personal computer PC.
FIG. 3 reproduces a program execution of a program "Transparent". In a first program step, a data word is read by the data interface COMP of the personal computer PC. When this data word is not a beginning of a transparent data word sequence, then a return is made to the program start and it waits for the next data word. When the data word is a "Start Character" for data words to be sent (start information, message), it is stored in a waiting queue of a memory unit of the personal computer PC, and the data words subsequently transmitted from the PC are interpreted as start information and are likewise stored in a waiting queue. The data words (message) following thereupon are subsequently received and stored until the end of the message transmitted by the PC is recognized. When the memory capacity of the waiting queue in the memory unit of the microprocessor module MP is exhausted, then the control unit of the personal computer PC is initiated to interrupt the data stream until memory capacity is again present in the waiting queue. When the received data word is a command to end the transparent mode, then a branch is undertaken to the program start of the program "START V.24"; otherwise, a jump is made to the starting address of the program "Transparent" in order to receive the next data words.
FIG. 4 reproduces a program execution of a program "Start Device" that controls an address or data exchange between the microprocessor module MP and the E2 data interface of the telecommunication equipment T. The program "Start Device" begins with a program portion "Power up Reset" that effects an activation of the V.24 and of the E2 interfaces. Following thereupon, data of the telecommunication equipment T (telephone type) connected to the circuit arrangement (see FIG. 1) are read and deposited in a memory unit of the microprocessor module MP. A program branch following thereupon evaluates the poll addresses coming from the telecommunication equipment T. In the no branch, the program waits for the next poll address. In the yes branch, a question is asked whether data follow the addresses. When data follow the addresses, these are read and, in the case of the transparent mode, are forwarded to the PC; when the transparent mode is not active in the microprocessor module MP, this part of the program is skipped over. A check is carried out in a program branch unit following this program module to see whether all data words have already been read out from the waiting queue, i.e. the memory unit. In the no branch, the data words are transmitted to the telecommunication equipment T. When the waiting queue of the memory unit has already been completely read out, then, in the yes branch, the reception of the data words is acknowledged by the telecommunication equipment T. The program waits for the next poll address after the execution of the program step in the no branch or yes branch.
Although various minor changes and modifications might be proposed by those skilled in the art, it will be understood that I wish to include within the claims of the patent warranted hereon all such changes and modifications as reasonably come within my contribution to the art. | A circuit arrangement is disclosed for data conversion in an asynchronous, bidirectional data transmission between a serial data interface of a personal computer and a serial data interface of an expansion point of a communication equipment, particularly a subscriber terminal equipment. The procedures implemented in the microprocessor module of the circuit arrangement convert data for the selection of a telecommunication subscriber into a pulse sequence corresponding to the communication equipment, and also convert communication procedures between the personal computer and a communication equipment as well as status requests of performance features of the communication equipment. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of copending International Patent Application PCT/EP2004/014188 filed on Dec. 13, 2004 and designating the United States, which was not published under PCT Article 21(2) in English, and claims priority of U.S. patent application Ser No. 10/736,448 and of European Patent Application EP 03 028 803.9, both filed on Dec. 15, 2003, which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a method for preparing a solution of a refolded, recombinantly expressed or chemically synthesized eukaryotic membrane protein in monodisperse form, to methods for preparing a crystalline form of a recombinantly expressed or chemically synthesized membrane protein, to a crystalline form of a recombinantly expressed or chemically synthesized eukaryotic membrane protein, and to a crystalline form of a complex of a recombinantly expressed or chemically synthesized eukaryotic membrane protein and of an accessory agent.
[0004] 2. Related Prior Art
[0005] Methods of these kinds and crystalline forms of proteins are generally known in the art.
[0006] Membrane proteins are of great pharmacological interest because of their importance as therapeutic and/or diagnostic targets. The most important exponents of membrane proteins are G-protein-coupled receptors (GPCRs), ion channels, and transport proteins.
[0007] Since the human genome has been deciphered the existence of about 350 GPCRs is known, without including the olfactory and gustatory receptors. The GPCRs analyzed in detail so far are almost exclusively very important pharmacological targets. For example, the nociceptin receptor is of great relevance in pain therapy. There are many companies doing research on antagonists against the nociceptin receptor in order to develop a potent analgesic. Comparable can be said for what concerns the opiate receptors.
[0008] Another receptor which is very well examined concerns the β-adrenergic receptor. Antagonists against that receptor are responsible for the regulation of blood pressure.
[0009] Many cytokine receptors play an important role in connection with inflammations and allergies. In the middle of interests herewith is the CXCR1 receptor.
[0010] Another not very well analyzed group of receptors are the so-called frizzled receptors. To that group belong 10 receptors which inter alia are involved in embryogenesis.
[0011] Also the rhodopsin which is located in the eye belongs to the GPCRs in the broadest sense, with rhodopsin being the only membrane receptor that naturally occurs in large amounts. All other receptors are only present in small amounts in the cell membrane.
[0012] Dysfunctional ion channels have been described in connection with many diseases, such as cystic fibrosis, diabetes mellitus, myotonia, epilepsy, and others.
[0013] Because of the enormous pharmaceutical importance of the membrane proteins there is a need for the finding of substances which are able to interact with membrane proteins, e.g. for their usage as an inhibitor or activator of a GPCR.
[0014] By the known high-throughput-screening (HTS) methods it is not possible to find agonists, antagonists or inverse-agonists for/against membrane proteins, e.g. GPCRs, in a satisfactory, time-saving and effective manner. The possible variations with chemical compounds are about 10 60 . Via the current HTS methods it is impossible to use that available chemical space. This is verified by the poor amount of registered drugs in the last years which are based on new innovative structures.
[0015] By means of new methods like the so-called in silico-screening or the “rational drug design” (RDD) it is possible to find new ligands for membrane proteins more efficiently and faster than with the HTS methods.
[0016] The prerequisite for the performance of an in silico-screening or RDD is the availability of the 3D-structure of the protein and thus of large amounts of such membrane protein in monodisperse form. In this context the term “monodisperse” is to be understood in the sense of a condition of a substance, e.g. a membrane protein, which is given if said substance has been purified, having a uniform particle size and being dissolved in an appropriate solvent. Furthermore, in order to provide especially well-suited starting material for a crystallization process the protein should be correctly folded without having any posttranslational modifications.
[0017] What concerns soluble, non-membrane proteins it is very often possible to obtain a solution of large amounts of monodisperse protein which subsequently can be crystallized in order to elucidate their three-dimensional structures. In fact, today the crystallization of soluble proteins is more or less a standard procedure.
[0018] More or less the same applies for bacterial membrane proteins which can be natively expressed, purified and, sometimes, even crystallized; cf. Ostermeier C., and Michel H. (1997), “Crystallization of membrane proteins”, Current Opinion in Structural Biology, 7: 697-701.
[0019] The situation is totally different with eukaryotic membrane proteins, such as GPCRs. In the case of producing the membrane protein by expressing it as a recombinant protein, e.g. in E. coli bacteria, one usually will obtain the membrane protein in form of so-called inclusion bodies. Those inclusion bodies are aggregates of insoluble, non- or misfolded membrane protein. Only a small fraction will be obtained as natively folded protein and/or will even be present as a solution of monodisperse protein. Therefore, by usage of common methods, the yield of monodisperse membrane proteins is very small. The problems concerning the purification of membrane proteins for crystallization purposes are e.g. described in Ostermeier C., and Michel H., loc.cit.
[0020] A method for preparing a part of a special kind of membrane protein, namely of cytochrome P450 monooxygenase, is described in the WO 03/035693, whereby said part being localized beyond the membrane and is, therefore, actually not a membrane protein. In Buchanan S. K. (1999), “β-barrel proteins from bacterial outer membranes: structure, function and refolding”, 9: 455-461, also a preparation of a very special kind of β-barrel proteins is described. These membrane proteins are very stable because of their high content of β-pleated sheets. However, the methods disclosed in both documents cannot be transferred to the preparation of other kinds of widespread membrane proteins, such as GPCRs or ion channels because of their high portions of α-helical sections.
[0021] In Urbani A., (2001), “Properties of detergent solubilized cytochrome c oxidase (cytochrome cbb 3 ) purified from Pseudomohas stutzeri”, FEBS Letters 508: 29-35, a method for preparing a special kind of a bacterial membrane protein is disclosed. That known method has been adapted for production of small amounts of bacterial membrane protein cbb 3 and cannot be used for preparation of the most pharmacological interesting human membrane proteins, e.g. GPCRs, especially not for preparation of large amounts of membrane proteins sufficient for subsequent crystallization since in the known method the protein was selectively extracted from bovine retinal membranes.
[0022] Okada T. et al. (2000), “X-ray diffraction analysis of three-dimensional crystals of bovine rhodopsin obtained from mixed micelles”, Journal of Structural Biology 130: 73-80, disclose a method for preparation of the photoreceptor membrane protein rhodopsin. According to this known method the protein was selectively extracted from bovine retinal membranes and afterwards crystallized. This method is adjusted to a special kind of protein which is the only known GPCR being present in large amounts embedded in the retina. However, all other known GPCRs only occur in very small amounts within biological membranes. Therefore, that known method is not helpful for producing large amounts of most of the interesting GPCRs.
[0023] Document DE 199 39 246 A1 discloses a method by which large amounts of different kinds of membrane proteins folded into their native or active structure can be produced. With that method a membrane protein is provided solubilized in a first detergent which is then changed for a second detergent. Herewith, the further above mentioned problem concerning the inclusion bodies problem is solved via a refolding procedure. A problem with that known method is that no solution of refolded membrane protein in monodisperse form is obtained, and that the membrane proteins are not present in a sufficiently homogenous form.
SUMMARY OF THE INVENTION
[0024] Therefore, it is an object of the present invention to provide a reliable method by which a solution of large amounts of refolded eukaryotic membrane protein in monodisperse form can be obtained and which is also simple to handle. Furthermore, the new method should not be limited to the preparation of a special kind of membrane protein but should also be applicable to widespread membrane proteins such as GPCRs. Moreover, the method should use bacterial expression systems in order to provide sufficient amounts of membrane protein.
[0025] According to the present invention, this object is achieved by providing a method for preparing a solution of a refolded, recombinantly expressed or chemically synthesized eukaryotic membrane protein in monodisperse form, comprising the steps of: (a) providing of membrane protein solubilized in a first detergent, (b) inducing refolding of said membrane protein into its native or active form, and (c): performing a size exclusion chromatography on said solution of refolded membrane protein.
[0026] Herewith the problem underlying the present invention is totally solved.
[0027] The inventors have realized that with that method it is ensured that the provided membrane protein will be obtained in monodisperse form. It was especially surprising that by means of steps (a) to (c) a homogenous solution of membrane protein being refolded into its active form is yielded. One would rather expect that additional measures had to be carried out, for separating unwanted non-active protein from the desired active protein. However, according to the invention the only step needed further to refolding is a size exclusion chromatography according to step (c), e.g. by the use of a Superdex 200 column, by which step protein of a homogeneous size or shape, e.g. monomeric protein, is separated from protein of a size different to that, e.g. from non-monomeric protein. By this size exclusion chromatography also dimeric protein can be separated e.g. from mono-, tri-, tetra-, penta-, hexameric etc. protein. In the case of ion channel proteins which, in most cases, consist of several subunits, it is mostly even desirable to separate the fully assembled channel, e.g. the tetrameric or pentameric protein, from individual subunits or partially assembled ion channels.
[0028] A further advantage of that method is that it is not necessary to isolate the interesting protein out of a biological membrane which would require to provide large amounts of biological raw material as starting material, even though the yield of membrane protein would still be scanty. In contrast, by the usage of recombinantly expressed or chemically synthesized protein well-established molecular expression systems and chemical synthesis methods, respectively, can be applied which are capable of producing sufficient amounts of membrane protein for, e.g., a subsequent crystallization.
[0029] The membrane proteins yielded according to the invention are sufficiently homogenous and monodisperse, e.g. for a subsequent usage in a crystallization procedure for elucidating their three dimensional structure.
[0030] Furthermore, by means of the inventive method also widespread and pharmacological important eukaryotic membrane proteins such as GPCRs can be obtained in large amounts, i.e. the method is not limited to the preparation of untypical and less interesting kinds of e.g. bacterial membrane proteins or β-barrel proteins.
[0031] The generic term “size exclusion chromatography” comprises all physico-chemical separation methods by which substances, e.g. membrane proteins, can be separated from each other on account of their different sizes. Examples for those chromatographic methods are filtration, gel filtration/chromatography, liquid chromatography, gas chromatography, high pressure liquid chromatography (HPLC), adsorption/affinity chromatography including metal chelate affinity chromatography, ion exchange chromatography, reversed phase chromatography, hydroxyapatite chromatography, hydrophobic interaction chromatography, chromatofocusing and other techniques well known in the art.
[0032] According to the invention it is preferred if between steps (a) and (b) a further step (a′) is performed by which a lipid is added to said membrane protein solution.
[0033] The inventors have found out that due to the addition of a lipid into the solution containing the first detergent the refolding process is favored and the long-term stability of the refolded protein is improved, i.e. the lipid stabilizes the functional conformation of the membrane protein.
[0034] With the new method it is preferred if step (b) comprises step (b′) by which said first detergent is exchanged for a second detergent.
[0035] This measure has the advantage that on account of the exchange of the detergents, e.g. a strong denaturating first detergent for a mild second detergent, the solubilized membrane protein which possibly originates from an inclusion bodies preparation, can be efficiently transferred into its native or active form. This procedure is described in more detail in DE 199 39 246 A1 the content thereof is herewith incorporated in this application by reference.
[0036] An alternative procedure according to the invention relates to step (b) comprising step (b″) by which said first detergent is diluted to an adequately low concentration.
[0037] This measure also ensures an efficient transfer of the solubilized denaturated membrane protein into its native or active form, whereas herewith e.g. the usage of a second detergent for inducing the refolding procedure is dispensable.
[0038] With the new method it is preferred if said membrane protein is selected from the group consisting of: receptors, preferably from the family of G-protein-coupled receptors (GPCRs), ion channels, transport proteins as well as partial sequences, homologous sequences, mutated sequences and derived sequences of aforementioned group members, whereby it is further preferred if said membrane protein is a mammalian, e.g. a human protein.
[0039] This measure has the advantage that herewith the pharmacologically most important membrane proteins being involved in several diseases will be covered. It is now possible for the first time by means of the method according to the invention to prepare large amounts of synthetically and/or recombinantly produced active GPCRs.
[0040] According to a preferred embodiment said membrane protein is provided as a histidine-tagged fusion protein.
[0041] An expressed histidine-tagged membrane protein has the advantage that it can be purified simply by metal chelating chromatography, for example by usage of a NiNTA column. Furthermore, the so tagged protein can even be purified in denatured state. The preparation, purification and handling of histidine-tagged fusion proteins is well-known and well-established in the art.
[0042] According to a further preferred measure said membrane protein is provided in form of inclusion bodies, preferably as a bacterially expressed protein, more preferably as an E. Coli expressed protein.
[0043] The provision of the interesting membrane protein in form of inclusion bodies has several advantages. Inclusion bodies are insoluble protein aggregates consisting of biologically inactive and not correctly folded protein. Inclusion bodies are relatively homogenous and purified for what concerns the contained protein, and can be handled in a simple way and e.g. further purified. Moreover, inclusion bodies contain large amount of protein which can be subjected to a refolding process. By the usage of a bacterial or of the E. coli expression system a technically mature tool is applied which is well-established in most molecular biological laboratories. In addition, the above-mentioned insolubility problem concerning the inclusion bodies is hereby managed in a simple manner, namely by refolding the aggregated protein as in step (b).
[0044] It is also preferred if said membrane protein is provided in form of inclusion bodies being synthesized by means of a cell-free expression system, preferably of the Rapid Translation System (RTS).
[0045] By this measure a suitable cell-free in vitro expression system, e.g. the so-called “Rapid Translation System” (RTS, Roche Diagnostics) is used by which up to 5 mg of the desired protein can be synthesized within 24 hours. The usage of RTS is especially advantageous since it produces much more recombinant membrane protein than traditional cellular expression systems.
[0046] With the method according to the invention it is preferred if said added lipid is selected from the group consisting of: naturally extracted phospholipids and synthetic phospholipids; especially brain polar lipid extract, phosphatidyl choline, phosphatidyl ethanolamine, cholesterol, phospholipid, ergosterol, asolectin, sphingomyelin, DOPA. Preferably, said lipid is added in step (b) to a final concentration of about 0.01 to 5 mg/ml, more preferably of about 0.05 to 2 mg/ml, and even more preferably of about 1 mg/ml.
[0047] As the inventors have realized, best results in preparing refolded monodisperse membrane protein will be obtained if one of the afore-listed lipids is used. The phosphocholine can originate from soybean or hens' egg, the phospholipid can originate from soybean, brain polar lipid extract can originate from pork, and phosphatidyl ethanolamine can originate from sheep brain. Furthermore, the inventors have ascertained that said indicated concentrations will further optimize the yield.
[0048] According to the invention it is also preferred if said first detergent is selected from the group consisting of: FOS-choline-8 (N-octylphosphocholine), FOS-choline-9 (N-nonylphosphocholine), FOS-choline-10 (N-decylphosphocholine), FOS-choline-11 (N-undecylphosphocholine), FOS-choline-12 (N-dodecylphosphocholine), FOS-choline-13 (N-tridecylphosphocholine), FOS-choline-14 (N-tetradecylphosphocholine), FOS-choline-15 (N-pentadecylphosphocholine), FOS-choline-16 (N-hexadecylphosphocholine), and N-laroyl-sarcosine. Preferably, said first detergent is provided in a final concentration of about 0.1 to 5, more preferably of about 0.5 to 4, furthermore preferably of about 1% (w/v).
[0049] The inventors have surprisingly found out that the usage of such harsh detergents is advantageous in order to effectively obtain a monodisperse protein preparation. With the indicated concentrations it is ensured that the provided membrane protein in step (a) will be completely unfolded, in order to transfer it into an active and monodisperse form in step (b) and (c). The detergents can e.g. be obtained at Anatrace Inc., Maumee, USA.
[0050] It is further preferred if in step (b) additionally SDS and/or urea is added.
[0051] By the addition of SDS (sodium dodecyl sulfate), as a strong synthetically anionic detergent, and/or of urea (carbamide), as another strong detergent, it will be ensured that contaminating protein, e.g. thrombin which possibly was used in order to cleave off a fusion part of the protein, is removed. Of course, the SDS and/or urea can subsequently be removed for allowing the membrane protein adopting its native or active form.
[0052] With the new method it is also preferred if said second detergent is selected from the group consisting of: maltosides; alkyl phosphocholines having a chain length of C8 to C16; bile acids and derivatives; alkyl-N,N-dimethyl glycin (alkyl=C8 to C16); alkyl glycosides (alkyl=C5 to C12); glucamides; saccharide fatty acid esters. Furthermore, it is preferred, if said second detergent is provided in a final concentration of about 0.01 to 5, preferably of about 0.05 to 1, more preferably of about 0.1% (w/v).
[0053] The inventors have surprisingly realized that by the usage of those largely mild detergents the solubilized proteins will be subjected to a refolding process leading to sufficient amounts of natively refolded monodisperse membrane protein. In this connection the indicated concentrations will further optimize the results. Examples for maltosides are DDM (n-Dodecyl-β-D-maltoside, Lauryl maltoside) and TDM (Tridecyl maltoside), for bile acids are cholate and deoxycholate, for bile acids derivates are CHAPS ((3-[(3-Cholamidopropyl)-dimethylammonio]-1-propane sulfonate), CAPSO (C 32 H 58 N 2 O 8 S), BIG CHAP (N,N-bis-(3-D-Gluconamidopropyl)cholamide). Alkyl glycosides comprise all mono and disaccharides. Examples for glucamides are MEGA-8 (Octanoyl-N-methylglucamide), MEGA-9 (Nonanoyl-N-methylglucamide), MEGA-10 (Decanoyl-N-methylglucamide), HEGA (Decanoyl-N-hydroxyethylglucamide). Examples for saccharide fatty acid esters are sucrose monododecanate, T×100 (Triton X) 100c, OG (Octyl glycoside), OTG (Octyl thioglycoside), C8E5 (Pentaethylenglycol octyl ether), C12E9 (POE 9 dodecyl ether), CYMAL®-5 (5-Cyclohexyl-1-pentyl-®-D-maltoside), CYMAL®-6 (6-Cyclohexyl-1-hexyl-®-D-maltoside), CYMAL®-7 (7-Cyclohexyl-1-heptyl®-D-maltoside), C12 DAO (Dodecyl dimethyl amino N-oxide), C10 DAO (DDA; Decyl dimethyl amino N-oxide) and Anzergent 3-14 (Tetradaecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate.
[0054] Within the frame of the new method it is preferred if in step (b) said exchange is carried out via a chromographic method, preferably via the use of a nickel-NTA column, and/or of a ion exchange column, and/or of an affinity column, and/or of a metal chelate column.
[0055] By the usage of a chromatographic method, especially by using the indicated well-characterized and effectively functioning columns, the exchange of the detergents can be performed in a simple and easy-to-handle manner. After the addition of the chromographic column material to the sample solution, the unfolded solubilized membrane protein binds to that material which in turn can be pelleted via centrifugation. The supernatant, i.e. said first detergent and where applicable said lipid, can then be removed and changed for said second detergent. Alternatively, dialysis can also be used for exchanging the detergents.
[0056] According to a further development of the new method, within step (c) said second detergent is exchanged for a third detergent, wherein said exchange preferably is also carried out via a chromographic method, preferably by using a nickel-NTA column, and/or an ion exchange column, and/or an affinity column, and/or a metal chelate column, and/or a Superdex 200 column. That third detergent is preferably selected from the group consisting of: maltosides; alkyl phosphocholines having a chain length of C8 to C16; bile acids and derivatives; alkyl-N,N-dimethyl glycin (alkyl=C8 to C16); alkyl glycosides (alkyl=C5 to C12); glucamides; saccharide fatty acid esters.
[0057] Depending on the individual membrane protein it might be advantageous to incubate the refolded protein in the presence of a third detergent. The inventors have realized that the indicated detergents are particularly suited. The addition of the third detergent favors the growing of possibly wanted membrane protein crystals, since it provides an advantageous environment therefor.
[0058] According to a preferred embodiment of the method according to the invention, after step (b) the following further step (b″″) is performed: reconstitution of said refolded membrane protein into proteoliposomes.
[0059] The reconstitution into proteoliposomes is performed according to standard methods. As the inventors have found out, the reconstitution into proteoliposomes is especially advantageous for membrane proteins since herewith the physiological environment of such proteins is imitated. As a result of this for membrane proteins consisting of several subunits, such as ion channels, an aggregation, i.e. an oligomerization of the several subunits to an entire ion channel can be observed. In this case after the performance of this reconstitution step active protein will be obtained. For monomeric proteins, such as G-protein-coupled receptors, which might already be active after the induction of the refolding according to step (b), the stability and activity is further increased by said reconstitution into proteoliposomes. It can also be observed that due to the reconstitution monomeric G-protein-coupled receptors accumulate to functional dimers.
[0060] It is preferred if after step (b″″) the following further step (b″″) is performed: resolubilization of said reconstituted membrane protein from out of the proteoliposomes.
[0061] This measure has the surprising advantage that the resolubilized membrane protein is now even highly stable in solution. The resolubilized membrane protein, if applicable in aggregated form consisting of several subunits in the case of ion channels, is therefore especially appropriate for subjection to a method for preparing a crystalline form thereof.
[0062] According to the invention it is preferred if before step (b″″) the following step (b′″) is performed: performing a size exclusion chromatography on said solution of refolded membrane protein.
[0063] By this further measure it is ensured that monomeric proteins are obtained, unspecific protein aggregation and contaminants are removed and monomer fractions are provided for the subsequent reconstitution into proteoliposomes. The size exclusion chromatography is performed according to conditions known in the art e.g. the kind of column is adapted to the molecular size of the membrane protein or of its monomeric subunit, respectively.
[0064] Another object of the present invention relates to a method for preparing a crystalline form of a recombinantly expressed or chemically synthesized eukaryotic membrane protein, preferably selected from the group consisting of: receptors, preferably from the family of G-protein-coupled receptors, ion channels, transport proteins, as well as partial sequences, homologous sequences, mutated sequences and derived sequences, recombinant forms of aforementioned group members; comprising the steps of: (a) providing a solution of said membrane protein in monodisperse form, and (b) incubating the solution for growing of membrane protein crystals, wherein step (a) is performed according to the aforementioned new method. Preferably, transition from step (a) to step (b) occurs without interposition of a separation step for separating of protein folded into its native or active form, from protein not folded into its native or active form.
[0065] From a skilled person's view it was totally surprising and against the current knowledge on the field of protein crystallization that just by performing the further above-described new method such a homogenous and monodisperse solution of membrane protein refolded into its native or active form can be obtained which in turn can directly be subjected to the crystallization procedure. Quite the contrary, one would expect that first it would be compulsory to screen for correctly folded, i.e. active membrane proteins which on the other hand are to be separated from misfolded proteins, and that only then the crystallization procedure could be initiated.
[0066] With that afore-mentioned method it is preferred if in step (a) an accessory agent is added to said solution, preferably said agent is selected from the group consisting of: proteins including ligands of membrane receptors, receptors, peptides, antibodies, haptens; nucleic acids including aptamers; organic compounds including ligands of membrane receptors, lipids, sugars; anorganic compounds; drugs; prodrugs.
[0067] This measure has the advantage that herewith a so-called “co-crystallization” is enabled, by which the structure of a complex of, for example, a receptor and its ligand can be analysed. In this case the ligand represents the accessory agent and can be the naturally occurring ligand, a modified ligand having e.g. a higher affinity to the receptor, a drug, etc. As a result thereof, the binding position of the ligand may be found out and the ligand could be modified what concerns its characteristics, e.g. its affinity to the receptor.
[0068] Furthermore, in many cases the stability of the membrane protein is increased by the addition of an accessory agent, e.g. an antibody, so that the growing of membrane protein crystals herewith is facilitated or even just enabled.
[0069] According to a preferred development of this method, step (b) is performed according to standard crystallization screenings by “hanging drop” or/and “sitting drop” vapor diffusion, or/and micro batch, or/and micro dialysis, or/and free interface diffusion technique, said standard crystallization screenings are preferably selected from the group consisting of: Hampton Research Crystal screens, Molecular Dimensions screens, Emerald Biostructures screens, and Jena BioScience screens.
[0070] The inventors have realized that for obtaining membrane protein crystals currently used standard crystallization procedures can be applied. Especially the listed methods yield good results in connection with the new method. This finding is advantageous since one of the main problems in the area of protein crystallization so far concerns the establishment of a crystallization protocol individually adapted to the protein of interest. This means a very time-consuming and hardly to automatize approach. Contrariwise, the invention avoids the workout of such an individually made protocol since the current screening methods are well suited.
[0071] In connection with the standard screenings it is preferred if the “sitting” or “hanging drop” consisting of about 200 nl of membrane protein solution having a concentration of about 1-100 mg/ml, preferably 10 mg/ml of protein, and of about 1 nl-10 ml, preferably 200 nl of precipitant solution, and wherein the reservoir containing about 10 μl-100 ml, preferably 100 μl of precipitant solution.
[0072] Within that indicated ranges, as the inventors have recognized, the conditions for well formed membrane protein crystals are particularly optimal. The volumes and concentrations of the solutions are herewith in good coordination.
[0073] Furthermore it is preferred if said precipitant solution has a pH value of about pH 6.5-10 and comprises about 0-0.5 M, preferably 0.1 M Tris/HCl and/or Hepes/NaOH and/or NaK phosphate at that given pH value; about 5-40% (w/v) of a polyethylene glycol (PEG) and/or polyethylene glycol mono methylether (PEG MME) with a molecular weight of about 1,000-10,000, preferably 2,000-6,000, more preferably 4,000.
[0074] By this measure optimized conditions for growing of membrane protein crystals regarding crystal size and diffraction quality are provided.
[0075] A further object of the present invention relates to a crystalline form of a recombinantly expressed or chemically synthesized eukaryotic membrane protein, preferably selected from the group consisting of: receptors, preferably from the family of G-protein-coupled receptors, ion channels, transport proteins, as well as partial sequences, homologous sequences, mutated sequences and derived sequences of aforementioned group members.
[0076] The inventors have succeeded for the first time in producing recombinantly expressed or chemically synthesized membrane proteins in crystalline form. As explained at the outset the newly provided protein crystals are very important tools for developing new drugs, e.g. by means of in silico-screening.
[0077] This before-mentioned subject-matter according to the invention also includes crystallized membrane proteins which originally have been recombinantly produced, e.g. by the usage of a yeast, CHO or insect cell expression system, and which therefore have been directly provided to the crystallization procedure in active or native form, i.e. the performance of an additional refolding step for providing active and correctly refolded protein had not been necessary. It shall be understood that also classic bacterial, e.g. E. coli expression systems can be used in order to provide sufficient amounts of recombinant membrane protein.
[0078] Up to now, there have been no examples in the art for successful preparation of membrane protein crystals starting from recombinantly produced membrane protein. However, crystals made of recombinant proteins have several advantages. Firstly, these kinds of proteins can be provided in large amounts, e.g. contrary to the method described by Okada et al., loc.cit., where it is required to isolate the GPCRs from biological membranes. Furthermore, by the usage of recombinant expression systems one can also obtain seleno-variants of membrane proteins. In view of the crystallization procedure the structure determination, e.g. by multiple wavelength anomalous dispersion (HAD), is greatly facilitated and accelerated. Moreover, the data quality is improved compared to traditional methods, e.g. multiple isomorphous replacement (MIR).
[0079] According to the invention it is preferred if said crystallized membrane protein is prepared according to the beforehand-mentioned method.
[0080] The inventors have succeeded in developing the afore-described method which concerns a simple manageable approach by means of which large amounts of the listed membrane proteins for a subsequent crystallization procedure can be produced. Furthermore, by the reliable provision of correctly refolded and monomeric protein the actual crystallization procedure can even be performed according to standard protocols, which is why costly and time-consuming tests for developing suitable crystallization conditions are no longer necessary. Such crystallization methods can then be applied to membrane proteins produced directly in its active form, i.e. without requiring refolding steps.
[0081] Another object of the present invention is a crystalline form of a complex of a recombinantly expressed, or chemically synthesized eukaryotic membrane protein, preferably selected from the group consisting of: receptors, preferably from the family of G-protein-coupled receptors, ion channels, transport proteins, as well as partial sequences, homologous sequences, mutated sequences and derived sequences of aforementioned group members, and of an accessory agent, whereby it is preferred if said complex is prepared according to the preferred embodiment of above-mentioned method concerning the addition of an accessory agent.
[0082] As described above, the crystalline form of such a complex is e.g. very useful in order to develop new ligands of receptors having modified characteristics compared to naturally occurring ligands, for example being utilizable as drugs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0083] FIG. 1 shows the crystallized form of the sphingosin 1 phosphate receptor (gpr3),
[0084] FIG. 2 shows the crystallized form of the cannabinoid receptor 1 (CB1).
DESCRIPTION OF PREFERRED EMBODIMENTS
Example 1
Production of an Expression Vector with cDNA for Membrane Protein
[0085] DNA sequences for several membrane proteins are listed in the EMBL database, in most cases, they do not have introns. With the help of primers, the required DNA can be produced via PCR from genomic DNA or via RT-PCR from mRNA.
[0086] This DNA is then cloned into an expression vector, which was constructed for the expression of a fusion protein. The tag part protein can be e.g. an histidine tail (his), as described in the art, e.g. in Sambrook, J. and Russell D. W. (2001), “Molecular cloning—A Laboratory Manual”, Cold Spring Harbor Laboratory Press, New York, which is herewith incorporated by reference.
[0087] Vectors for the expression of sphingosin 1 phosphate receptor (gpr3) and of cannabinoid receptor 1 (CB1) as histidine-tagged glutathione-S-transferase (GST) fusion proteins were produced. The expression vectors were transformed into a cell line which expressed the fusion proteins. The proteins are, in this procedure, not incorporated into the membrane, but exist at least partly aggregated in form of inclusion bodies in cytoplasm and are, thus, not correctly folded.
Example 2
Expression of Recombinant Membrane Protein in the Form of Inclusion Bodies
[0088] The cDNAs of above mentioned membrane proteins were each, inframe, inserted into the vector pGEX2a-c-His. This vector contains downstream of the Tac-promotor the sequence encoding glutathione-S-transferase and a subsequent thrombin cleavage site, followed by a polylinker sequence and, finally, six histidine codons and a stop codon.
[0089] The vectors were transformed into E. coli strains derived from strain K12, e.g. BL21 or BLR. The protein expression was induced by adding IPTG, and the cells were harvested after further three hours. After lysozyme treatment and homogenization by sonification, the membranes and inclusion bodies were separated from the soluble proteins by centrifugation.
Example 3
Solubilization of the Inclusion Bodies and Thrombin Cleavage
[0090] For each membrane protein 50 ml of inclusion bodies were centrifuged for 10 min, at 4° C. at maximum speed. Each pellet was resuspended in 450 ml of the following buffer: 25 mM Tris/HCl pH 8.5, 250 mM NaCl, 1 mM DTT, and put on ice for 15 min.
[0091] Subsequently, each ice cold sample was subjected to sonification for 3 min at 50% “duty cycle” and 80% power in a Bandelin Sonoplus microsonicator using a rosette cell. It has to be ensured that the sample will be kept cool.
[0092] Afterwards 50 ml of following first detergent and lipid containing buffer solution was added to each sample: 10% L-lauroyl-sarcosine (LS) in TBS pH 8.5 containing 0.1 mg/ml brain polar lipid extract (Aranti Polar Lipids Inc., Alabaster, USA; Cat. No. 14110). The membrane protein was herewith solubilized.
[0093] To each sample 12,500 U thrombin was added, in order to cleave the GST fusion part. Each sample was slowly stirred overnight at 20° C. Afterwards, the membrane protein was solubilized. The sample was centrifuged for 20 min at ≧20,000 g at 4° C.
Example 4
Inducing Refolding of Membrane Protein
[0094] 25 ml of NiNTA column material equilibrated in 50 mM Hepes/NaOH pH 7.5, 250 mM NaCl and 1% LS was added to 500 ml of solubilized membrane protein, e.g. of gpr3 or CB1. The sample was incubated for 30 to 60 min, afterwards the column material comprising the immobilized membrane protein was transferred either into an empty column or an XK26/30 column (Amersham, Buckinghamshire, UK). The following steps were performed at 4° C., i.e. all buffers used were stored on ice.
[0095] The column was washed with 10 column volumes (CV) of 50 mM Hepes/NaOH pH 7.5, 250 mM NaCl, 0.1 mg/ml brain polar liquid extract, 1 mM GSH, 1 mM GSSG, 1% LS; followed by washing with 10 CV of 50 mM Hepes/NaOH pH 7.5, 250 mM NaCl, 1% FOS-choline-14 (C14, N-tetradecylphosphocholine; second detergent).
[0096] Elution was performed using 3 CV of elution buffer, i.e. 50 mM Hepes/NaOH pH 7.5, 500 mM NaCl, 300 mM imidazole (pH 7.0), 0.1% C14. Therefor the column was incubated with the incubation buffer for 15 min at room temperature. Subsequently, fractions of 8 ml each were eluted. Aliquots of solubilized membrane protein, flow through, wash and elution fractions were separated by SDS PAGE followed by Coomassie blue staining in order to examine purity and yield.
[0097] The first three elution fractions were pooled. A typical yield is about 22 mg of protein, i.e. of gpr3 or CB1, concentrated at 1.45 mg/ml. The solution was concentrated to 10 to 15 mg/ml using an Amicon Ultra 15 ml 30 kD ultrafiltration concentrator.
Example 5
Reconstitution into Proteoliposomes
[0000] (a) Preparation of Monomeric Membrane Protein
[0098] The pooled fractions are subjected to a size exclusion chromatography, i.e. a preparative gel filtration. In the case of the reconstitution of a G-protein-coupled receptor this can be performed by means of a Superdex 200 26/60 column (Amersham Biosciences, Buckinghamshire, UK). This column was equilibrated using a buffer consisting of 50 mM Tris pH 7.5, 250 mM NaCl, 0.5% FOS-choline-14. The eluted monomeric fractions were subsequently subjected to the reconstitution process.
[0000] (b) Reconstitution into Proteoliposomes
[0099] For each milligram of membrane protein 25 mg of lipid are applied. The reconstitution buffer comprises 50 mM Tris pH 7.5, 250 mM NaCl.
[0100] The volume of each sample is 50 ml. 5 ml liposomes (10 mg/ml) were added to 3 ml 10×reconstitution buffer. This mix was filled up to 35 ml with doubled distilled water. 0.01% FOS-choline-14 was added. The sample was thoroughly mixed. 10 ml protein having a concentration of about 0.2 mg/ml were added, the sample was thoroughly but carefully mixed, foam has to be avoided. The sample was incubated at 18° C. in a rotator for six hours.
[0101] 10 ml Calbiosorb (Calbiochem, EMD Biosciences, San Diego, USA) were added to each sample in order to remove surplus detergent. The samples were again incubated over night in the rotator at 18° C. Each 5 ml of Calbiosorb material were given to 10 ml MOBITEC column, equilibrated, the sample was added, separated and the flow was collected in ultracentrifugation vials for the Ti-45 rotor.
[0102] A subsequent centrifugation at 40,000 rpm for 60 min was performed in the ultracentrifuge using the Ti-45 rotor. The supernatant was removed and the pellet was resuspended into 5 ml cold reconstitution buffer. Afterwards the sample was filled up to 60 ml. A second centrifugation step at 40,000 rpm for 60 min in the ultracentrifuge using the Ti-45-rotor was performed. The pellet was resuspended into 2 ml cold reconstitution buffer.
[0000] (c) Resolubilisation of the Reconstituted Membrane Protein
[0103] The reconstituted protein was diluted in ice-cold (4° C.) buffer containing 20 mM Hepes pH 7.0, 200 mM NaCl up to 5 ml. FOS-choline-16 as a 10% stock solution was directly added: The membrane protein was reconstituted in 300 mg lipid (6×50 mg). Therefore, a surplus of FOS-choline-16 has to be added, i.e. 600 mg FOS-choline-16, 6 ml 10% stock solution. Each of the five samples was diluted up to 4 ml, subsequently 1 ml 10% FOS-choline-16 stock solution was added, resulting in a final concentration of 2% FOS-choline-16 in 5 ml. The samples were incubated at 4° C. overnight in a roller.
[0104] The samples were centrifuged in 5 ml ultracentrifugation vials at 50,000 rpm for 50 min at 4° C. The supernatants were pooled. 3 ml NiNTA were added to the pooled supernatants after an equilibration in Tris NaCl, pH 7.5. In order to bind the membrane protein to the NiNTA material, the whole sample was incubated for one hour at 4° C. in a rotator. The sample was transferred into a 5 ml plastic column. The column was washed with 30 ml washing buffer containing 20 mM Hepes pH 7.0, 200 mM NaCl, 0.2 mg/ml molch lipid, 0.05% FOS-choline-16. Using 20 ml elution buffer containing 20 mM Hepes pH 7.0, 200 mM NaCl, 0.2 mg/ml molch lipid, 300 mM imidazol, 0.05% FOS-choline-16, fractions of 1 ml were eluted.
[0105] The fractions were subjected to UV measurements. Positive fractions were concentrated by means of Millipore ultracentrifugation tubes to a volume of about 2.5 ml. This volume was loaded onto a PD10 column (chromatography column of Amersham Bioscience). Therefore, the PD10 column was equilibrated with 20 ml buffer comprising 20 mM Hepes pH 7.0, 200 mM NaCl and subsequently with 5 ml buffer comprising 20 mM Hepes pH 7.0, 200 mM NaCl, 0.1% FOS-choline-16. 2.5 ml resolubilized membrane protein were loaded onto the column. The subsequent elution was performed by using 3.5 ml buffer comprising 20 mM Hepes pH 7.0, 200 mM NaCl, 0.05% FOS-choline-16.
[0106] The eluate of about 3.5 ml was concentrated by means of Millipore ultracentrifugation tubes to 10 mg/ml.
Example 6
Size Exclusion Chromatography
[0000] Sphingosin I phosphate receptor (gpr3)
[0107] A Superdex 200 10/300 GL column (Amersham Biosciences, Buckinghamshire, UK) was equilibrated using 1.5 CV of 20 mM Hepes/NaOH pH 7.0, 200 mM NaCl, 0.1% C14. 8 times 100 μl of concentrated protein solution, i.e. about 0.8 mg, were added to the column. Elution was performed using 1.5 CV of above mentioned elution buffer. Fractions of 200 μl each were collected. The fractions were analyzed by means UV absorption at 280 nm and SDS PAGE followed by Coomassie blue staining.
[0108] Alternatively, a Superdex 200 26/60 prep grade column was used. In this case, approximately 50 mg of protein were added to the column. Fractions of 5 ml each were collected.
[0109] Monomeric fractions were pooled. The pooled sample was concentrated to 10 mg/ml using an Amicon Ultra 10 ml 30 kDa device. A typical yield is 3 mg protein. In order to confirm whether the sample is purified, i.e. consisting exclusively of monomeric membrane protein, 10 μl of concentrated protein solution was subjected to an analytic gel filtration using a Superdex 200 10/300 GL column, 20 mM Hepes/NaOH pH 7,0, 200 mM NaCl, 0.1% C14.
[0110] Alternatively, the second detergent C14 was changed for a third detergent by performing the following procedure: A Superdex 200 10/300 GL column was equilibrated using 1.5 CV of 20 mM Hepes/NaOH pH 7.0, 200 mM NaCl, and third detergent (e.g. 0.01% FOS-choline-16, or 0.01% tetradecylmaltoside). 1 mg protein of each sample was subjected to a size exclusion filtration as described before. The monomeric fractions were pooled, the solution was concentrated to 10 mg/ml using an Amicon Ultra 15 ml 30 kDa device.
[0000] Cannabinoid Receptor (CB1)
[0111] A Superdex 200 26/60 prep grade column was equilibrated using 1.5 CV of 20 mM Hepes/NaOH pH 7.0, 200 mM NaCl, 0.1% C14. 5 ml of concentrated protein solution, i.e. about 50 mg, were applied to the column. Elution was performed using 1.2 CV of above mentioned elution buffer. Fractions of 5 ml each were collected.
[0112] Monomeric fractions were pooled. The pooled sample was concentrated to 10 mg/ml using a Millipore ULTRA 100 kDa. The pooled sample was checked via a Superdex 200 HR 10/30 column using 20 mM Hepes/NaOH pH 7.0, 200 mM NaCl, 0.1% C14.
[0113] Alternatively, a Superdex 200 10/300 GL column was used. In this case, approximately 1-2 mg of protein were applied in a volume of 100 μl to the column. Fractions of 0.2 ml each were collected.
[0114] Monomeric fractions were pooled. The pooled sample was concentrated to 10 mg/ml using an Amicon Ultra 15 ml 100 kDa device. A typical yield is 5-15 mg protein. In order to confirm whether the sample is homogenous, i.e. consisting exclusively of monomeric membrane protein, 10 μl of concentrated protein solution was subjected to an analytic gel filtration using a Superdex 200 10/300 GL column with 20 mM Hepes/NaOH pH 7.0, 200 mM NaCl, 0.1% C14 as running buffer.
[0115] Alternatively, the second detergent C14 was exchanged for a third detergent by performing the following procedure: A Superdex 200 26/60 prep grade column was equilibrated using 1.5 CV of 20 mM Hepes/NaOH, pH 7.0, 200 mM NaCl, and a third detergent (e.g. 0.01% FOS-choline-16, 0.01% tetradecylmaltoside, or 0.1% lauryldimethylamine N-oxide (LDAO)). 1 mg protein was subjected to a size exclusion filtration as described before. The monomeric fractions were pooled, the solution was concentrated to 10 mg/ml using an Amicon Ultra 15 ml 100 kDa device.
Example 7
Crystallization Set-Up
[0000] Sphingosin I Phosphate Receptor (gpr3)
[0116] The crystallization was performed according to “sitting drop” vapour diffusion technique. Therefor a CrystalQuick 288 plate with circular wells (Greiner, Germany) was used.
[0117] The reservoir solution was 0.1 M Tris/HCl, pH 8.5; 24% polyethyleneglycol (PEG) 4000.
[0118] Each drop was consisting of 200 nl protein solution of example 5, and of 200 nl reservoir solution.
[0119] The screening for crystals was performed according to standard screening procedures, e.g. sparse matrix sampling technology. Corresponding commercialized screens can be found at Hampton Research Inc., Aliso Viejo, USA.
[0120] Crystals have been developed after 10 days as shown in FIG. 1 . Cannabinoid receptor 1 (CB1)
[0121] The crystallisation was performed using the “sitting drop” vapour diffusion technique. The screening for crystals was conducted using commercially available sparse matrix screens. Corresponding screens can be found at Hampton Research Inc., Aliso Viejo, USA.
[0122] The reservoir solution was 0.1 M Hepes/NaOH, pH 7.0, 40% polyethyleneglycol monomethylether (PEGMME).
[0123] Each drop was consisting of 100-200 nl protein solution of example 5, and of 100-200 nl reservoir solution.
[0124] Crystals grew after 10-14 days at 18° C. as shown in FIG. 2 . | The present invention relates to a method for preparing a solution of a refolded, recombinantly expressed or chemically synthesized eukaryotic membrane protein in monodisperse form, to methods for preparing a crystalline form of a recombinantly expressed or chemically synthesized membrane protein, to a crystalline form of a recombinantly expressed, or chemically synthesized eukaryotic membrane protein, and to a crystalline form of a complex of a recombinantly expressed or chemically synthesized eukaryotic membrane protein and of an accessory agent. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent Application Ser. No. 60/229,027 filed on Aug. 31, 2000, the entirety of which is hereby incorporated into the present application by reference thereto.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved straddle type all terrain vehicle (ATV) and more particularly to the structure, placement and orientation of an air intake within the ATV.
2. Description of Related Art
FIG. 1A shows a related art ATV 700 including a frame 702 , a pair of front wheels 704 , and a pair of rear wheels 706 . The frame 702 has mounted thereto a body 708 , which is shown to include front facie 710 and rear fenders 712 . Additionally, the ATV 700 includes a fuel tank 714 mounted thereto.
For the ATV 700 shown in FIG. 1A , the rear wheels 706 are supplied power from an engine 718 . The engine 718 generates power by combusting a mixture of fuel and air. The fuel is delivered to the engine 718 from the fuel tank 714 by a suitable means, such as a fuel pump. Air is pulled from the atmosphere through an air intake system, indicated at 720 , mixed with the fuel in a carburetor 743 , and combusted within a chamber of the engine 718 . An inlet 722 of air intake system 720 is positioned between the seat 710 and fuel tank 714 . Accordingly, the inlet 722 is protected from debris and water entering therethrough.
FIG. 1B shows a schematic view of the air intake system 720 and engine 718 . As shown, the air intake system 720 includes a pair of intake tubes 730 , which on one end thereof provide the inlet 722 , and are connected to a noise suppressing enclosure or silencer 732 . The silencer 732 is a substantially voluminous enclosure, which serves to attenuate intake roar of the engine 718 . The silencer 732 includes a hollow molded body 734 with an upwardly facing opening 736 . A closure member (e.g., lid) 738 is detachably mounted (such as with clips 739 ) to the body 734 thereby sealing the opening 736 . It is noted that the sealing of the opening 736 may be facilitated by a pliable sealing member 740 disposed between the body 734 and closure member 738 . The silencer 732 is also connected to an intake duct 742 , which is connected at an opposite end to the carburetor 743 . As shown, an air filter 744 is disposed within the silencer 732 and may be connected to the end of duct 742 to filter or otherwise separate particulates through the air flowing from the air intake system 720 prior to delivery to the carburetor 743 . As shown in FIG. 1A , the silencer 732 is positioned just behind the engine 718 . The intake tubes 730 extend from the silencer 732 , along an upper portion of the engine 718 , to the position between the fuel tank 714 and the seat 710 .
The main drawback of the air intake system 720 shown in FIGS. 1A and 1B , stems from the proximate positioning of the air intake 720 relative to the engine 718 . In particular, the silencer 732 is positioned rearwardly of the engine 718 and adjacent thereto. Additionally, the intake tubes 730 are positioned above the engine 718 , between the engine 718 and the seat 710 , as is conventional. As such, the intake tubes 730 and silencer 732 are exposed to a substantial amount of heat generated by the engine 718 , which serves to raise the temperature of intake air prior to combustion. Relatively high temperature intake air disadvantageously reduces engine efficiency and power output.
FIG. 2A is a perspective view showing a related prior art ATV 100 described in application Ser. No. 09/057,652 incorporated by reference into the provisional application No. 60/229,027 referenced above. The ATV 100 includes a pair of front wheels 102 and a pair of rear wheels 103 . The front wheels 102 are covered by front fenders 117 and the rear wheels 103 are covered by rear fenders 116 . A front rack 105 is provided above the front fenders 117 and the rack 106 is provided above the rear fenders 116 . A pair of apertures or ventilation openings 120 , provided in the rear fenders 116 , supply intake air to a radiator and fan assembly 170 (FIG. 2 B), which is generally beneath a seat 107 . A pair of handle bars 110 is used to steer the ATV 100 .
FIG. 2B is a top plan view of the ATV 100 shown in FIG. 2A , with the seat 107 being removed and the front and rear fenders 116 , 117 being shown in phantom. The front and rear wheels 102 and 103 are supported by a main frame 121 , while a subframe 122 , which is connected to the main frame 121 through joints 124 , supports the radiator and fan assembly 170 . A suitable type of power unit, e.g., an engine 150 , is preferably capable of simultaneously driving the front and rear wheels 102 and 103 through a suitable transmission, although rear wheel drive only ATVs are also contemplated. The ATV 100 also includes a carburetor 152 , an exhaust pipe 154 , a muffler 156 , and an air intake system 200 , which is shown in greater detail in FIG. 3 .
FIG. 3 is a schematic view illustrating an intake air system 200 . An inlet end 212 of a front air intake pipe 214 is positioned at the front of the ATV 100 adjacent the steering column, just below a mounting plate 115 for mounting equipment, e.g., an instrument panel and/or a dash board. The inlet end 212 is positioned at substantially the highest point of the ATV 100 to substantially eliminate entry of mud or water caused either by immersion when traversing relatively deep water or by splashing when traversing wet terrain. The front air intake pipe 214 is connected to a sleeve 216 and a rear air intake pipe 217 that leads to the air box 201 , which is positioned just below a rear portion of the seat 107 . Clamps 210 secure the front air intake pipe 214 to the sleeve 216 , and the sleeve 216 to the rear air intake pipe 217 . Intake air from the air box 201 is supplied to the carburetor 152 using a hose 206 that is held by a clamp 210 to the carburetor 152 . Air is supplied to an engine valve cover (not shown) and the engine 150 using a vent hose 222 , clamps 218 and 219 , PCV valve 221 , oetiker clamp 227 , vent hose 226 , “Y” fitting 228 , hoses 229 and 230 and fitting 233 . The air filter 155 is placed in the air box 201 along with a foam member 220 . Air intake tubes 211 fit within the air filter 155 . A cover 226 is secured by cover brackets 232 to the air intake box 201 .
The related art air intake system 200 suffers from at least two main drawbacks. The first main drawback is that the cumulative length of the air intake pipes 214 , 216 and 217 may create vibration and sound resonance that affects the fuel-to-air air ratio in the carburetor 152 . Vibration and sound resonance adversely affect air pressure in the carburetor 152 , thereby causing fuel-to-air to ratio to be either lean or rich, therefore adversely affecting performance of the engine.
The second main drawback to the related art intake system 200 is schematically illustrated in FIG. 4 . In some circumstances, the ATV 100 is used in conditions where it is necessary to cross bodies of water, such as rivers and streams. It is for this reason that the inlet end 212 of the front end intake pipe 214 is positioned at the highest point of the ATV 100 , near the steering column and just below the mounting plate 115 , as discussed previously. However, when the ATV 100 is crossing a deep stream having a predetermined depth D nominal , a wall of water or wave W having a depth D max greater than the predetermined depth D nominal is created and travels upwardly against the front of the ATV 100 . This phenomenon can introduce water into the inlet end 212 of the front air intake pipe 214 , which is undesirable. Typically, the wave W dissipates just rearward of the front wheels 102 , and the depth D wake of the water behind the wave W is less than the predetermined depth D nominal of the water because of the wake created by the ATV 100 .
Furthermore, both of the prior art intake systems 200 and 720 share an additional drawback in that the respective inlets 212 , 722 are located just in front of the rider. With this arrangement, the rider is exposed to a substantial degree of noise and vibration emanating from the inlets 212 , 722 .
SUMMARY OF THE INVENTION
It is one aspect of the invention to avoid the main drawbacks of the related art, including positioning an air intake system relative to the engine such that air traveling through the air intake system is not exposed to relatively high temperatures prior to delivery to the engine.
It is another aspect of the invention to avoid other drawbacks of the related art, including providing an ATV with a short intake pipe that avoids sound resonance and vibration that can adversely affect the fuel-to-air ratio in the carburetor.
It is another aspect of the invention to provide an ATV in which the inlet end of air intake pipe is positioned to avoid interaction with a water wave created at the front of the vehicle when the vehicle travels through water.
It is yet another aspect of the present invention to provide an ATV in which existing ventilation openings on the ATV can he used to supply intake air to both the radiator and fan assembly and the air intake system.
It is yet another aspect of the present invention to provide an ATV in which the inlet end of the air intake pipe is positioned to prevent exposure of the rider to a substantial degree of noise and vibration emanating from the inlet end.
According to one preferred embodiment of the present invention, an all terrain vehicle having a frame and front and rear wheels suspended from the frame includes a pair of rear fenders attached to the frame, the rear fenders having at least one ventilation opening, an engine mounted on the frame between the pair of rear fenders, the engine providing motive power to at least one of the pair of front and rear wheels, and an air intake box connected to the frame and supplying intake air to the engine, the air intake box including an intake pipe connected to and receiving intake air from the at least one ventilation opening.
In embodiments, the vehicle may further comprise a radiator connected to the frame, the radiator drawing intake air from the at least one ventilation opening. In addition, the vehicle may comprise a seat located between the rear fenders, the intake pipe including an inlet end positioned adjacent a rear lateral portion of the seat. The inlet end of the intake pipe is preferably positioned above the rear wheels so as avoid interaction with a water wave created at the front of the vehicle when the vehicle travels through water.
According to another preferred embodiment of the present invention, an all terrain vehicle comprises an engine, a seat having a front portion positioned above the engine, an air intake system operatively connected to the engine, and at least one opening adjacent a rear portion of the seat and supplying intake air to the air intake system.
In embodiments, the vehicle further comprises rear fenders positioned adjacent the engine, wherein the at least one opening is located on at least one of the rear fenders. The air intake system may also include an air box having an intake pipe positioned so as to avoid interaction with a water wave created at the front of the vehicle when the vehicle travels through water. Also, the seat may be located between the rear fenders, and the air intake system may include an intake pipe having an inlet end positioned adjacent the rear portion of the seat.
According to another preferred embodiment of the invention, a straddle type motor vehicle having front and rear wheels and being capable of traversing water having a predetermined depth includes an engine, an air intake box positioned adjacent the engine and at least one opening in communication with the air intake box. The at least one opening is positioned on the vehicle rearward of the front wheels and so that the height of the opening is greater than the predetermined depth of the water. The position of the at least one opening also helps to avoid water entering the at least one opening due to encountering a water wave created in front of the vehicle that has a wave depth greater than the depth of the water.
The vehicle may also include a frame that mounts the engine, and rear fenders may be attached to the frame, with the at least one opening being provided within at least one of the rear fenders. The at least one opening may comprise at least one opening provided on each of the rear fenders, and a radiator may be connected to the frame, the radiator being in communication with the at least one opening. The air intake box may include an intake pipe having an inlet end adjacent to only one of the rear fenders. Also, the vehicle may further comprise a seat provided between the rear fenders, the air intake box including an intake pipe having an air inlet positioned adjacent a rear lateral portion of the seat.
According to still another preferred embodiment of the invention, an all terrain vehicle having front and rear wheels comprises a frame from which the wheels are suspended, an engine mounted on the frame, a fender structure overlying at least the rear wheels, the fender structure including at least one aperture, and an air intake system in communication with the engine, the air intake system including an air box mounted on the frame, the air intake box having an intake pipe having an inlet end, the intake pipe being fastened with respect to the fender structure such that the inlet end is in communication with the aperture in the fender structure and is positioned rearward of the front wheels and higher than the rear wheels.
In embodiments of an all-terrain vehicle, the aperture in the fender structure may be a ventilation opening that supplies intake air to a radiator positioned adjacent the engine. Also, the intake pipe may include a clip that attaches to the fender structure.
These and other aspects of preferred embodiments of the invention will be described in or apparent from the following detailed description of preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will be described in conjunction with the following drawings, wherein:
FIG. 1A is a perspective view illustrating a related art ATV;
FIG. 1B illustrates an air intake system of the related art ATV shown in FIG. 1A ;
FIG. 2A is a perspective view illustrating another related art ATV;
FIG. 2B is a plan view of a frame of the related art ATV shown in FIG. 2A ;
FIG. 3 illustrates an air intake system of the related art ATV shown in FIGS. 2A and 2B ;
FIG. 4 is a schematic view of the related art ATV shown in FIGS. 2A and 2B as it travels through water;
FIG. 5 is a side view illustrating an air intake system according to one preferred embodiment of the invention;
FIG. 6 is a rear perspective view of the air intake system of FIG. 5 attached to a frame according to one preferred embodiment of the invention;
FIG. 7 is a front perspective view illustrating the air intake system and frame shown in FIG. 6 ;
FIG. 8 is a top view of the air intake system of FIG. 5 illustrating one embodiment of the manner in which the air intake box is connected to both the frame and fender structure;
FIG. 9 is an enlarged cross-sectional view along line IX—IX of FIG. 8 ;
FIG. 10 is a cross-sectional view along line X—X of FIG. 8 ;
FIG. 11 is a detail view of a portion of FIG. 10 ;
FIG. 12 is a front perspective view illustrating rear fenders with ventilation openings according to one preferred embodiment of the invention;
FIG. 13 is a front perspective view according to one embodiment of the invention illustrating the cover portion and the rear fenders in a disassembled state without the seat;
FIG. 13A is a top view of the cover portion and rear fenders shown in FIG. 12 ;
FIG. 13B is a front perspective view illustrating anther preferred embodiment of the invention; and
FIG. 14 is a schematic view illustrating one advantage of the placement of the inlet end of the air intake pipe when the vehicle travels through water, according to one preferred embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 5 illustrates an air intake system 300 according to one preferred embodiment of the invention. The air intake system 300 includes an air box 301 , which is a closed container provided with a lid 314 that is secured to a main body 351 of the air box 301 using clips 313 . The air box 301 is generally positioned beneath the seat 507 ( FIG. 12 ) towards a rear portion of the ATV 500 (FIG. 12 ). It is contemplated that the specific construction and placement of the air box 301 may be altered from that shown and described herein.
The air intake system 300 includes an air intake pipe 302 connected to the main body 351 of the air box 301 , toward the rear of the ATV 500 . The air intake box 301 includes a port 303 that is connected to and provides intake air to an outlet pipe 304 that leads to a carburetor 352 (FIGS. 6 and 7 ). The air box 301 also includes ports 305 A and 305 B, which are connected to vacuum pipe 306 A and engine ventilation pipe 306 B, respectively. The vacuum pipe 306 A is connected to the carburetor 352 and applies vacuum pressure from the carburetor 352 (generated by the engine 600 ) on a valve element (not shown) situated within the air box 301 . It is contemplated that the valve element may be used to control the quantity of intake air allowed to enter the outlet pipe 304 from the air box 301 . The engine ventilation pipe 306 B serves to vent components of engine 600 such as a crankcase and valve cover through respective ventilation pipes 307 , 308 . As shown in FIG. 5 , engine ventilation pipe 306 B includes a “Y” fitting 311 to connect both the crankcase and valve cover of the engine 600 via pipes 307 , 308 , respectively to the engine ventilation pipe 306 B. There are, of course, different configurations possible for the input to and output from the air box 301 dependent upon the particular design of the engine 600 .
The air box 301 includes an extension 353 provided on a portion of the air box 301 facing the front of the ATV 500 . The extension 353 is used to attach the air box 301 to the frame 120 (FIGS. 6 and 7 ), and the air box 301 also includes a bottom wall 330 that includes a pin 332 for engaging an aperture provided on the frame 120 , as described below.
FIGS. 6 and 7 are rear and front perspective views, respectively, illustrating one preferred embodiment for attaching the air box 301 to the frame 120 . The frame 120 may have a subframe similar to that shown in FIG. 2 B. Additionally, the frame 120 may include other members.
As compared to the arrangement shown in FIG. 3 in which the inlet end 212 of the intake pipe 214 is provided beneath the mounting plate 115 , the inlet end 312 of the intake pipe 302 is provided close to the air box 301 and towards the rear of the vehicle. One important advantage to this arrangement is that the length of the intake pipe 302 is significantly reduced as compared to the combined length of the intake pipes 214 , 216 and 217 shown in FIG. 3 . As such, the intake pipe 302 is much less apt to vibration, thereby helping to avoid or avoiding sound resonance that can adversely affect the fuel-to-air ratio in the carburetor 352 . Thus, the fuel-to-air ratio in the air intake system 300 can be more precisely controlled to provide for better engine operating performance. Further the air intake system 300 has less parts and is also easier to assemble and maintain, thereby reducing costs for maintenance, labor and parts.
As shown in FIG. 6 , the frame 120 also includes a support plate 126 for supporting the bottom wall 330 of the air box 301 . As shown in FIG. 7 , the support plate 126 includes an aperture 122 for receiving the pin 332 of the air box 301 .
FIG. 8 is a top plan view illustrating one preferred connection arrangement between the air intake system 300 and the frame 120 . FIG. 8 also illustrates one preferred arrangement for connecting the air intake system 300 to a connecting wall 502 that is positioned between and preferably formed integrally with the fender structure, e.g., rear fenders 516 (FIG. 12 ). Referring back to FIG. 6 , the frame 120 includes a frame adapter member 125 connected to the frame 120 using, for example, a standard nut and bolt assembly 142 (FIG. 8 ), or other suitable fastener. The adapter member 125 includes a lateral extension 127 on each side of a main support bar 123 of the frame 120 . The lateral extension towards the air box 301 includes a bolt hole through which a bolt 340 ( FIG. 9 ) extends to secure the air box 301 to the adapter member 125 of the frame 120 . As shown in FIG. 9 , which is an enlarged cross-sectional view along line IX—IX of FIG. 8 , the extension 353 of the air box 301 and one of the lateral extensions 127 of the frame 120 (on the side of the main support bar 123 facing the air box 301 ) are bolted together using the bolt 340 and nut 342 .
As shown in FIGS. 8 , 10 , 13 and 13 A, the air intake pipe 302 extends beneath the connecting wall 502 and extends upwardly through a bottom wall 506 defined by one of a plurality of channels 590 ( FIG. 13 ) that are preferably formed as part of the fender structure. Referring to FIG. 13A , the bottom wall 506 may be provided with a U-shaped aperture 505 , through which the intake pipe 302 extends. Alternatively, or in addition, the intake pipe 302 can be guided through an aperture (not shown) formed in a side wall of the connecting wall 502 , rather than in the bottom wall 506 of, one of the channels 590 . As shown in FIGS. 8 and 11 , the connecting wall 502 also includes a slot 504 for receiving a fastener formed as part of the intake pipe 302 . For example, a clip 315 made of a resilient material and integrally formed with or connected to the intake pipe 302 can be provided to fasten the intake pipe 302 to the connecting wall 502 . The detail view of FIG. 11 shows that the clip 315 extends through the connecting wall 502 to secure the intake pipe 302 with respect to the connecting wall 502 such that the inlet end 312 of the intake pipe 302 is fastened in a predetermined position with respect to an aperture or a ventilation opening 520 ( FIG. 13 ) on the fender structure, e.g., the rear fenders 516 of the ATV, as described below.
Like the ATV 100 shown in FIG. 1 , the ATV 500 according to the invention has fender structure that includes rear fenders 516 on either side of a seat 507 , as shown in FIGS. 12 and 13 . The rear fenders 516 include apertures or ventilation openings 520 . Also, since the power unit (engine) is positioned at least in part beneath the seat 507 , additional ventilation openings 547 are preferably provided in the base portion of the seat 507 in order to ensure proper ventilation of the engine compartment. The ventilation openings 547 preferably extend to the side of the seat 507 since accessories, which could block the openings, may be provided in front of the base portion of the seat 507 . FIG. 12 also shows protection grills 530 that are connected to a cover portion 513 . The protection grills 530 prevent large objects from entering into the channels 590 ( FIG. 13 ) that lead to the radiator and fan assembly 170 , which are more fully described in U.S. Pat. No. 6,296,073 and A allowed pending application Ser. No. 09/057,652.
FIG. 13 schematically shows the position of the airbox 301 next to the connecting wall 502 between the rear fenders 516 . The intake pipe 302 of the air box 301 is guided beneath the connecting wall 502 and through a bottom wall 506 of the channels 590 (via aperture 505 ) so that the inlet end 312 has access to intake air that enters at least one of the ventilation openings 520 . The slot 504 for receiving the clip 315 that is integrally formed with or connected to the intake pipe 302 is also shown. As shown in FIGS. 10 and 11 , the slot 504 is positioned such that the inlet end 312 of the intake pipe 302 is positioned to receive intake air through at least one of the ventilation openings 520 . As such, the ventilation openings 520 provide intake air to both the radiator and fan assembly 170 as well as the intake air system 300 . As shown in FIG. 13 , The inlet end 312 of the intake pipe 302 is positioned adjacent a rear lateral portion of the seat 507 . In this position, the inlet end of the intake pipe 302 is positioned rearward of the front wheels 102 , and preferably above one of the rear wheels 103 . As also shown, the inlet end 312 of the intake pipe 302 curves to the right side of the ATV, toward a right one of the rear fenders 516 . In this manner, in the illustrated preferred embodiment, the air intake pipe 302 draws air from substantially only one of the ventilation openings 520 , which is on the right side of the ATV, as shown in FIG. 13 .
It is also contemplated that the intake pipe 302 may curve to the left, so as to draw air substantially from the left side of the ATV, or may be disposed proximate the center of the ATV, between the rear fenders 516 , so as to draw air from both ventilation openings 520 . Furthermore, the intake pipe 302 may be configured such that an intake opening 360 provided by the intake pipe 302 is arranged in a generally forwardly facing direction so as to confront connecting wall 502 . In this manner, there is a decreased likelihood that foreign objects or water may enter the intake opening 360 .
Alternatively, the intake pipe 302 may be configured such that the intake opening 360 faces toward a rear of the ATV, or laterally toward the center of the ATV. Obviously, foreign objects and water are substantially prevented from entering the intake opening 360 in any of these arrangements due to the orientation of the intake opening 360 relative to the direction of air flow (and perhaps water flow, if water enters the openings 520 ) through the channels 590 toward the radiator and fan assembly 170 .
Another contemplated embodiment is shown in FIG. 13 B. As shown, the seat 507 includes a seat frame 800 . The seat frame 800 serves to provide rigidity to the seat 507 and allow padding materials to be mounted thereto. Additionally, the seat frame 800 may form a hollow enclosure 802 at a rear portion 804 of the seat 507 . As also shown, the intake pipe 302 connects to the enclosure 802 . It is contemplated that an air intake opening, indicated at 806 , may be formed, for example, within the seat 507 itself or between the rear portion 804 of the seat 507 and the connecting wall 502 . In this manner, air may pass through the intake opening 806 , through an aperture 808 in the enclosure 802 , and to the intake pipe 302 .
The enclosure 802 may serve to facilitate the attenuation of noise and vibration emitted by the intake pipe 302 . It is also contemplated that attenuation features, such as ribs, may be formed on an interior of the enclosure 802 to further attenuate noise and vibration.
Furthermore, it is contemplated that the enclosure 802 may be used either in lieu of or in addition to the air box 301 .
FIG. 14 is a schematic diagram illustrating one advantage to the arrangement shown in the preferred embodiments illustrated herein. In FIG. 14 , the ventilation openings 520 and/or the inlet end 312 of the intake pipe 302 are/is positioned at a height that is greater than the depth D wake of the wave and is preferably greater than the predetermined depth D nominal of the water. In addition, the inlet end 312 is positioned on the vehicle so as to avoid entry of water due to encountering a water wave W at the front of the ATV 500 , wherein the water wave W has a depth D max greater than the predetermined depth D nominal . Moreover, positioning of the inlet end 312 of the intake pipe 302 as indicated in FIG. 14 takes advantage of the fact that the depth D wake of the water behind the wave W is less than the depth of the water D nominal in front of the wave W due to the wake created by the ATV 500 .
While preferred embodiments of the invention have been shown and described, it is evident that variations and modifications are possible that are within the spirit and scope of the preferred embodiments described herein. | An all terrain or straddle type vehicle is provided with an air intake system having an air intake pipe with reduced length thereby avoiding unnecessary vibration which may adversely affect the fuel-to-air ratio of the engine, thereby improving engine performance. Also an inlet end of the air intake pipe is positioned so that the vehicle's capability for traversing water of a predetermined depth is improved. The height of the inlet end of the intake pipe is greater than the predetermined depth of the water to protect against water entering the air intake pipe due to encountering a water wave created in front of the vehicle that has a depth greater than the predetermined depth of the water. Additionally, openings in rear fenders of the vehicle channel intake air to both a radiator/fan assembly and the air intake system. | 1 |
BACKGROUND OF THE INVENTION
The present invention generally relates to an electronic typewriter equipped with a text memory, and more particularly to such type of electronic typewriter which prevents deletion of format data included in a line to be deleted when data stored in the text memory are deleted per line, so that an arrangement of characters is not disturbed.
There have been provided electronic typewriters equipped with a text memory which stores data comprising character data which correspond to characters to be printed and format data which are located between the character data and concerned with an arrangement of the characters. In such an electronic typewriter, characters are printed according to the character data stored in the text memory and arranged according to the format data such as carriage return data, which are located between the character data. The format data includes, for example, tab position data which moves a printing position of a character to the next preset print starting position (tab position), left margin position data which specifies the first position of each line, and right margin position data which specifies a right end of each line, so that the first positions of plural character groups of lines are appropriately aligned with the tab position when a table or chart is formed, and the first positions or the last character positions of lines are, respectively, aligned with each other. However, since the format data are located between the character data in the text memory, the format data included in a line to be deleted are deleted together with the character data of the line when the character data of the whole line are deleted, resulting in disarrangement of the characters.
SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide an electronic typewriter equipped with a text memory, which saves format data included in a line to be deleted, to prevent the format data from being erased, when the whole line is deleted.
According to the invention, there is provided an electronic typewriter equipped with a text memory, comprising:
(1) line deleting means for deleting data for a line stored in the text memory;
(2) detecting means for detecting the format data in the line to be deleted by the line deleting means; and
(3) saving means for saving the detected format data in a predetermined position of the text memory so that the format data detected by the detecting means are not deleted during a line deleting operation.
In the above arrangement, referring to FIG. 1, when characters constituting the line to be deleted by the line deleting means, i.e., character data, are deleted in due order, the format data in the line to be deleted are detected by the detecting means and, the detected format data are saved in a predetermined position of the text memory by the saving means. Consequently, when the character data for the whole line are deleted by the line deleting means, only the format data remain undeleted from the text memory. Therefore, characters that follow are arranged in accordance with the undeleted format data and the disarrangement of characters is eliminated when the line deleting operation is performed.
According to an advantageous embodiment of the invention, the typewriter further comprises displaying means which displays at least a part of one line of plural lines comprising the character data stored in the text memory. The display means displays a desired line of the plural lines by a scrolling operation, and thereby specifies a group of the character data corresponding to the line desired to be deleted by the line deleting means.
According to another advantageous embodiment, the line deleting means is operable in an edit mode. It is appreciated that this edit mode be established by said scrolling operation of the displaying means.
In accordance with one form of the invention, the keyboard of the typewriter includes a delete key and a code key which, when operated simultaneously, enables the line deleting means to be operable to delete the data for a desired line.
According to a preferred embodiment of the invention, the line deleting means is adapted to move a group of data corresponding to the line to be deleted, to a part of the text memory, and the detecting means sequentially detecting said group of data so that the saving means saves the detected format data in a position following a data group constituting a line preceding the line to be deleted. In this instance, the line deleting means sequentially deletes the character data of said group of data which have not been deleted by the detecting means.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will become more apparent from reading the following description of the preferred embodiment taken in connection with the accompanying drawings in which:
FIG. 1 is a perspective view of one embodiment of the electronic typewriter of the invention;
FIG. 2 is a block diagram showing a circuit provided for the embodiment of the electronic typewriter shown in FIG. 1;
FIG. 3 is a flow diagram showing an operating process of the embodiment shown in FIG. 1; and
FIGS. 4(a)-(c) are respectively views of a text memory illustrating the changes of memory contents according to the operation of the embodiment shown in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
To further clarify the present invention, a preferred embodiment of an electronic typewriter equipped with a text memory will be described in greater detail, referring to FIGS. 1-4.
There is shown in FIG. 1 an electronic typewriter to which the present invention is applied. The electronic typewriter is provided with a printing unit or assembly 10 and a keyboard unit or assembly 12. The printing assembly 10 has a plexiglass cover 14 which is pivotally mounted at a position adjacent to an upward rear edge thereof. The plexiglass cover 14 acts as a paper guide when pivoted to its open position, i.e. when it is inclined slightly rearwardly. In the printing assembly 10, i.e. under the plexiglass cover 14, a platen 16 is supported on a frame in the horizontal direction and a carriage 18 is provided movably in a direction parallel to the platen 16. The carriage 18 has a print head 20 fixed thereto, which moves in relation to a sheet of paper held on the platen 16 so that desired characters, such as letters, symbols, and numerals, and other data are printed on the print paper according to a predetermined arrangement.
The keyboard assembly 12 is provided with a power switch 22 on its side surface and a multiplicity of operation keys on its top surface. These operation keys consist of character keys 24 on each of which an alphabet is imprinted, a space key 26, a code key 28, a margin release key 30, a tab key 32, a left margin key 34, a right margin key 36, a tab set key 38, a tab clear key 40, a delete key 42, a left cursor key 44, a right cursor key 46, a back space key 48, a carriage return key 50 and other keys. In the rear central part of the keyboard assembly 12, there is provided a multi-digit display 52 which displays multiple digits (16 digits or so) of characters and other data so that desired characters stored in a text memory (which will be described later) are displayed.
The electronic typewriter constructed as described above is provided with a circuit shown in FIG. 2. As shown, a CPU 54 is connected, via a data bus 56, with a keyboard 58, a ROM 60, a RAM 62, a print mechanism driver interface 64 and a display controller 66, which are contained in the keyboard assembly 12. The CPU 54 processes signals input from the keyboard 58 according to a program stored in the ROM 60 by use of a temporary memory function of the RAM 62, and causes the print mechanism driver interface 64 to drive a print mechanism 68 incorporated in the printing assembly 10 for printing characters on the print paper in a desired arrangement. The CPU 54 also causes the display controller 66 to drive the multi-digit display 52 for displaying characters corresponding to a desired part of a stored text. The RAM 62 serves as storage means and is provided with a format memory and the text memory. The format memory stores format data which are associated with the arrangement of characters such as margin position data and tab position data. The text memory stores a multiplicity of character data in the order of printing, and appropriately stores the format data which are located between the character data. The character data includes not only alphabets, numerals and symbols but also space data which is used to move a printing position. In other words, the character data are related to the movement of the carriage and used to change the printing position.
The operation of the electronic typewriter constructed as described above will be described, referring to FIG. 3.
Upon depression of the power switch 22 of the electronic typewriter, an initialize routine (not shown) is first executed, and various devices such as a counter and register are cleared. A step S1 is then executed to judge whether or not any of the keys disposed on the keyboard assembly 12 has been pressed. When the key has not been pressed, the step S1 is executed again. When the key has been pressed, a step S2 is executed to judge whether or not an edit mode has been selected. The edit mode is selected when an upward or downward scrolling operation is performed by concurrent depressions of the code key 28 and the left or right cursor key 44 or 46. When the edit mode has not been selected, another operation is executed, for example, a line feeding operation. Since such an operation is not directly related to the present invention, the explanation is omitted. The scrolling operation is utilized to move a displayed line upwardly or downwardly so that a desired line of multiple lines of the character data stored in the text memory are displayed on the multi-digit display 52. When the line deleting operation is performed, the line to be deleted is displayed on the multi-digit display 52.
In the step S3, whether or not the line deleting operation has been performed is judged. The line deleting operation is executed when the code key 28 and the delete key 42 are depressed simultaneously. When the line deleting operation has not been performed, a suitable operation not directly associated with the subject of the invention is executed. When the line deleting operation has been performed, a step S4 is executed. In the step S4, the first data of the line to be deleted is read. Then a step S5 is executed, in which the detecting means judges whether or not the data read in the step S4 is tab or margin position data. Namely, in the step S5, the format data is detected. When the read data is not tab or margin position data, the deleting operation is executed in a step S6 so that the read data is deleted. When the read data is tab or margin position data, a step S7 is executed whereby the saving means saves the margin or tab position data to protect it from being deleted from the text memory. Following the step S7, a step S8 is executed to judge whether or not the read data is the last data of the line to be deleted. That is, the step S5 and S7 are repeatedly executed for each data of the line to be deleted until the read data is judged to be the last data of the line. When all the characters of the line have been deleted except the format data, the deletion of the line is judged to have been completed in the step S8, and a main routine is then executed. Consequently, in the preferred embodiment of the invention, the steps S4, S6 and S8 mainly constitute the line deleting means. As a result, the contents of the text memory will be changed as exemplified in FIG. 4(a)-(c). Referring to FIG. 4(a), data for a text are usually located in a batch in the upward position of the text memory. When the line delete mode is selected, a group of data corresponding to the line to be deleted and the next line are moved to the downward position of the text memory as shown in FIG. 4(b). The data which have been moved downwardly are then read and deleted one by one in due order, beginning with the first data. When a tab or margin position data is detected during the reading operation, the detected data is saved in a position at the end of the data group located in the upward position of the text memory as shown in FIG. 4(c), whereby the saved data are not deleted.
Thus, in the above embodiment, if the deletion of one line is executed, the format data such as the margin and tab position data, which are included in the line to be deleted, are not deleted and are saved in the position at the end of a line preceding the line to be deleted. Accordingly, the embodiment of the present invention eliminates a possibility that printing positions of lines located following the deleted line will be disturbed due to the deletion of the format data.
While the present invention has been described in its preferred embodiment, it is to be understood that the invention is not limited thereto, but various changes and modifications can be made to the invention without departing from the spirit and scope of the invention. | An electronic typewriter equipped with a text memory for storing data including character data representing characters to be printed, and format data for arranging the characters to be printed, comprising a line deleting device for deleting data for a line stored in the text memory, a detector for detecting the format data associated with the line to be deleted, and a device for saving the detected format data so that the format data are not deleted from the text memory during a line deleting operation. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains generally to the field of oven heatable plastic coated paperboard containers and to processes for producing the same.
2. Description of the Prior Art
The most common containers for convenience foods which are to be heated within the container are formed of thin sheet aluminum or layers which include aluminum foil. Because of the relative high cost of such containers and because they generally cannot be used in microwave oven cooking, substantial efforts have been made to provide plastic coated paperboard cartons which can withstand oven heating.
Polyethylene is often used as a coating material for paperboard since it has good moisture impermeability and is easily adhered to many types of paperboard. However, polyethylene and many other types of common plastic coating materials do not have the resistance to melting at high temperatures required for very hot oven heating. Such coating polymers must also have adequate structural strength and abrasion resistance, as well as being compatible with food products.
Polyethylene terephthalate polyester is a particularly satisfactory coating material for oven heatable trays since it has a high melting temperature and good structural strength, and is compatible with and unaffected by most food products. However, it is well known in the art that it is difficult to obtain good bonding of polyethylene terephthalate to other materials and particularly to paperboard. In the past, such bonding has been accomplished by the use of adhesives or primers applied over the paperboard before a hot melt extrusion of the polymer is applied to the paperboard. The use of primers and adhesives is undesirable in packaging foods because such materials are capable of migrating into the contents of the food package.
A procedure for extrusion coating polyethylene terephthalate onto paperboard without the use of primers is shown in U.S. Pat. No. 3,924,013 to Kane, in which the paperboard is subjected to heating prior to being contacted with the hot melt extrusion. While such a process may be adequate for certain purposes, it is undesirable were the coated paperboard is to be die pressed into deep formed trays, since heating the paperboard reduces its moisture content and embrittles the board to thereby make it more subject to tearing upon die pressing. Deep pressed heatable containers are especially preferred since they do not require the use of adhesives or heat seals in order to form the edge walls of the tray. Trays formed by adhesively connecting the sides of the tray together or by heat sealing them together are subject to separation at the very high temperatures of oven heating, and the adhesive material may migrate into the food product. Pressing allows formation of smooth radius contoured corners, rather than sharp adhesively joined corners, which provides good heat distribution characteristics during oven heating.
SUMMARY OF THE INVENTION
The coated paperboard formed in accordance with the invention is especially suited to forming deep pressed trays which can be filled with food products and oven heated to temperatures of 400° F. The polyethylene terephthalate coating on the interior surface of the paperboard has a high degree of adhesion to the paperboard at initial room temperatures, at the freezing temperatures at which the food is stored, and at the 300° F. to 400° F. oven temperatures at which the food is heated. The coating is applied to the paperboard without the use of primers or adhesives which thereby eliminates a potential source of contamination of the food.
The paperboard substrate is selected to have good resistance to oven heating, low levels of contaminants which inhibit proper adhesion of the coating, and surface roughness characteristics which allow strong adherence of the coating to take place. The paperboard substrate, which has a thickness in the preferred range of 0.015 to 0.025 inch, is passed through a corona discharge device such that the selected surface of the paperboard receives a selected corona discharge energy sufficient to allow adhesion of the coating to the paperboard of at least 90 grams per linear inch. Generally, the corona energy density required will be at least 0.35 joules per square inch and preferably 2 to 5 joules per square inch. Surface treatment at this energy level prepares the surface and reduces the effect of contaminants in the surface which would tend to inhibit adhesion of the coating.
The corona treated paperboard is passed into a nip formed between a chill roll and a backup roll while a hot melt extrusion of polyethylene terephthalate is simultaneously passed into the nip between the corona treated side of the paperboard and the chill roll. The hot melt extrusion exits from the extruder at an initial temperature between 580° F. and 640° F. through an air gap before insertion into the nip at substantially the same speed as the forward moving paperboard. The air gap is adjusted such that the temperature of the extrusion at the time of contact with the paperboard is above the melting point of the polyethylene terephthalate such that the extrusion will still be in a substantially fluid state at the time that it contacts the paperboard so as to flow into the fibrous surface of the paperboard. At normal ambient temperatures (65° F. to 80° F.), the air gap and paperboard speed are preferably adjusted to provide a polymer residence time in the air gap of about 0.05 to 0.15 seconds. The chill roll is maintained at a temperature close to ambient so as to quickly chill the extrusion coating below its glass transition temperature to a substantially non-flowing state by the time the laminate of paperboard and coating leaves the chill roll.
Coated paperboard formed by the aforementioned process has adhesion between the polyethylene terephthalate coating and the underlaying paperboard of at least 90 grams per inch and preferably 200 to 500 grams per inch width. It has been found that adhesion levels generally increase with increases in corona energy density and in the thickness of the extrusion coating, but that adequate adhesion can be obtained at lower corona energy and more convenient coating thicknesses where the paperboard surface roughness is greater than selected minimum levels and the organic contaminants on the surface are below selected maximum concentrations.
For forming of deep die pressed trays, it is preferred that the moisture content of the paperboard be at least 10% by weight. Generally, the initial moisture content of the paperboard is not substantially effected by the corona treatment or extrusion process so that if adequate moisture is present in the initial paperboard, it will be maintained through the entire process. However, where additional moisture is required, the uncoated side of the paperboard can have a wetting liquid applied thereto, with the entire coated paperboard laminate being enclosed in a moisture proof wrapping for a period of several hours to allow the moisture to reach equilibrium distribution within the paperboard. Various types of paperboard substrates which have good resistance to heating can be utilized, such as boards formed from solid bleached sulfate pulps.
The exterior surface of the paperboard can be printed to provide decoration and product advertising material, while the polyethylene terephthalate coating itself can be pigmented with any desired color for aesthetic enhancement as well as concealing any browning of the paperboard that may take place at the high oven temperatures.
Further objects, features, and advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings showing coated paperboard material suitable for forming pressed heatable food trays and a process for producing the same.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic view of apparatus for treating and coating the paperboard.
FIG. 2 is an external perspective view of a pressed tray formed from the coated paperboard of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more particularly to the drawings, wherein like numerals refer to like parts in both views, a preferred embodiment of an apparatus for forming the coated paperboard of the invention is shown generally at 10 in FIG. 1. For exemplary purposes, a roll 11 of paperboard is shown which is unwound and passed through a corona discharge device 12. The corona discharge device 12 is shown only in schematic form in FIG. 1, with the plates of the device being represented by the dielectric roller 13 and the curved plate or shoe 14. The generator which provides the corona discharge voltages between the plates 13 and 14 is not shown in FIG. 1. The shape of the plate or shoe 14 is preferably curved to match the periphery of the roller 13 contacting the paper so as to provide a substantially uniform corona field to the paperboard. It is preferred that the corona discharge device have a capacity to provide corona discharge wattages of 100 to 600 watts per inch of width at 9.6 KHz over an air gap of approximately 0.060 inches. As explained below, the device 12 has the capacity to treat the side 11a of the paperboard facing the curved plate 14 with a corona energy density of at least 2 to 6 joules per square inch of paperboard surface at production speeds generally in the range of 100 to 500 ft. per minute.
The paperboard stock provided from the roll 11 may be formed in conventional manufacturing processes but is preferably formed with minimal additives or impurities and is uncoated on at least the upper surface 11a thereof.
It has been found that the effect of the corona treatment of the surface of the paperboard endures for a period of at least 10 days under normal temperature and humidity conditions following the corona treatment. Thus, although the paperboard is shown immediately being passed into extrusion coating equipment in FIG. 1, it is understood that the paperboard could be rolled up after corona treatment and extrusion coated at a later time.
The extrusion coating equipment shown in FIG. 1 includes an extruder 18 which feeds the hot molten polyethylene terephthalate into a sheet forming die 19. The molten extruded film 20 exiting from the die 19 passes through an air gap and thence into a nip formed between a chrome plated chill roll 21 and a backup roll 22. The paperboard is simultaneously passed into the nip such that the corona treated surface 11a of the paperboard comes into contact with the film in the nip. As the molten film 20 reaches the nip, its temperature has decreased to a temperature somewhat above the melting point of the polyethylene terephthalate material (m.p. approximately 480° F.). At this temperature, the film is still sufficiently molten that it can flow and conform to the surface fibrous of the paperboard, while quickly cooling below its glass transition temperature (approximately 179° F.) and solidifying by contact with the cooler chill roll 21 which is preferably maintained at a temperature close to ambient. The now solidified coating easily parts from the chrome plated chill roll and allows the laminate of paperboard and coating to be rolled up on a wind-up roll 23.
The finished coated paperboard product is especially adapted to use in forming press formed one-piece trays. Such trays are formed by placing a blank of the laminate with the coated side up over a female die and pressing downwardly thereon with a mating heated male die. An example of such a tray construction is shown in FIG. 2, wherein the finished tray includes a bottom panel 25, integrally connected side panel 26, and an integrally connected top flange 27. Because the die forming of such trays requires the paperboard to bend and stretch easily, it is important to the proper formation of the trays that the paperboard have a relatively high moisture content, in the range of 10% by weight or more. It is noted that in carrying out the process of the invention, the moisture content of the board is not substantially reduced. Furthermore, the process does not require heating of the paperboard in any manner, which minimizes the possibility of oxidizing or embrittling the fibers of the paperboard, or destroying inter-fiber bonds. If the initial paperboard, or the roll 11 does not have sufficient moisture content, the finished coated paperboard in the roll 23 may have a wetting liquid applied to the uncoated surface thereof which is allowed to seep through the paperboard over a period of time, preferably 10 to 24 hours. In order to minimize evaporation of the moistened board, it is preferable to wrap the moistened board in a polyethylene or other moisture proof wrapping until the paperboard is formed into trays.
High adhesion of the polyester coating to the paperboard is desired, preferably being a minimum of 90 to 150 grams per inch as measured transversely at a 180° pull angle and at a 5 inch per minute rate, or to the point were fiber tearing in the paperboard occurs. 90 grams per inch adhesion is the minimum acceptable level at which adhesion is maintained during die pressing, and a minimum of 150 grams per inch is preferred to prevent spontaneous delamination if the coated board is die cut. The factors most influencing adhesion are the degree of penetration of the polyethylene terephthalate into the paperboard, the roughness of the paperboard surface being coated, and the presence of chemical additives or contaminants in the paperboard. Generally, it has been found that the crystallinity of the laminated polyethylene terephthalate, and the commercial source of the polymer, do not substantially affect the adhesion of the coating to the paperboard.
The adhesive peel strength of the coating depends on both the mechanical and chemical aspects of the paperboard. The mechanical factors of the paperboard include the roughness of the paperboard surface and the fiber tearing strength of the paperboard in a direction toward its surface. These mechanical features affect the flow of molten or plastic polyethylene terephthalate into the paperboard surface at elevated temperatures and pressures as well as the spreading of peel forces over a wider area by the pulling of fibers. The roughness of the paperboard surface is the major contributor to the mechanical aspects of the final adhesion of the coating, and the roughness of the surface with the coating in situ increases with increases in the application weight of the coating. Additionally, less significant conditions which affect the flow of the extrusion into the paperboard are the polymer temperature at the time of contact with the paperboard, the laminating pressure at the nip between the back-up roll and the chill roll, and the contact time above the polymer melting point during laminating.
Chemical additives and contaminants in the paperboard also have been found to have a substantial effect on the strength of adhesion which is obtained. The strength of adhesion improves with decreasing concentrations of organic contaminants or additives, which can be measured quantitatively by the adsorption of an iodine stain applied to the paper. A positive relationship was found between the intensity of an iodine stain developed on the paperboard and the level of adhesion that could be developed when polyethylene terephthalate was extrusion laminated to the paperboard. The test is similar to one commonly used to detect the presence of organic compounds on thin-layer chromatography plates. The technique is effective in detecting materials such as oils, waxes, and certain paperboard additives such as wax and rosin size.
The stain test was carried out utilizing a Macbeth MS-2000 Spectrophotometer, a ceramic white plate standard provided with the Spectrophotometer, iodine crystals (Fisher Catalog No. I-36), and a rectangular developing tank (Fisher Catalog No. 5-718-16). The tests were conducted on paperboard which had been cut to sections of approximately 2 inches by 6 inches. 1 gram of iodine solid was emplaced in a glass exposure vessel which was covered for three hours to allow the iodine vapors to reach an equilibrium level. The paperboard samples were placed standing up in the exposure vessel and the vessel was covered for three hours to allow the iodine stain to develop. The samples were then removed and allowed to stand for three minutes to reduce excess iodine vapors, and the change in lightness-darkness (ΔL) of the sample versus the white plate standard was read on the Spectrophotometer. The iodine stain test is a test of relative concentrations of contaminants, and exact test readings may be expected to vary with changes in test equipment and whiteness standard.
It has been observed that the corona treatment of the paperboard surfaces does not decrease the concentration of additives and contaminants, as measured by the iodine stain test, but rather apparently neutralizes the effect of the contaminants where their concentration is initially low. It is theorized that the corona treatment produces bonding sites on the additives and contaminants so that the polyester coating can bond thereto. Other possible, although less likely explanations for the enhancement of the bonding, are that the additives and contaminants are oxidized in the presence of the corona or that the corona produces active sites for adhesion on the cellulose fibers of the paperboard itself. While the corona treatment of the paperboard surface provides increased adhesion of the polyester coating on paperboard substrates in general, optimum adhesion is obtained where the paperboard substrate meets preferred conditions of roughness and sufficiently low levels of contaminants. The effect of these factors are set forth in the following examples which are illustrative of the invention.
EXAMPLES 1-9
Polyethylene terephthalate coatings were applied to corona treated paperboard in accordance with the process of the invention set forth above at varying corona treatment levels. The paperboard was provided from four separate types of solid bleached sulfate paperboard having different surface characteristics, with each run of paperboard being passed through the corona device (Pillar Model Components AB 1326-3(-) and AB 1418-4(-)) and the extrusion coater at the rate of 175 ft. per minute. Polyethylene terephthalate obtained from Eastman as Eastman 6857 resin was used to coat 7 samples of paperboard, while 2 samples of paperboard were coated with resin obtained from Goodyear under the designation Goodyear VPE-5792, to determine if the source of supply of the polyester affected adhesion. The polyester resin was thoroughly dried, and then heated in the extruder to an exit melt temperature of 640° F. The extruded film passed through an air gap of approximately 2 inches and into contact with the corona treated paperboard surface. The chrome plated chill roll was maintained at a temperature of 60° F. The results of these tests are given in Table 1 below. In this table, the base board thickness and the polyester thickness were determined by measurement after separation of the polyester from the board, except where separation could not be obtained without fiber tearing, in which case nominal theoretical thickness are provided based on the expected thickness of the polyester coating.
TABLE 1__________________________________________________________________________ Adhesion Instron, Board Poly- polyester Basis Base Bendt- ester: to board Weight, Board sen thick- 180° ang., lbs/rm Corona- Iodine thick- rough- ness 5"/min.,Sam- 24×36× joules/ Stain ness ness at (mils), grams/25.ple 500' sq. in. (-.increment.L) mils 5 Kg Supplier 4mm width__________________________________________________________________________1 199 3.41 37 16.0 188 1.31 10-25 Goodyear2 232 2.81 15 18.5 123 1.34 55-225 Eastman3 258 2.11 20 21.1 351 1.36 120-380 Goodyear4 256 3.61 20 21.8 351 1.50 125-375 Eastman5 231 2.81 15 18.5* 123 1.50* CNS Eastman6 191 3.73 25 15.0 94 1.51 20-110 Eastman7 193 3.73 25 13.8 94 1.67 75-140 Eastman8 193 3.73 25 14.0 94 1.78 75-110 Eastman9 211 2.76 37 16.6 188 2.14 175-275 Eastman__________________________________________________________________________ CNS = Could not separate *Estimated value
Since similar tests without corona treatment yielded very low to no adhesion of polyester coating to paperboard for all of the above samples, the test results indicate that corona treatment provides some additional adhesion under virtually all conditions. However, it is noted from a comparison of samples 1 and 9 that a very large increase in adhesion was obtained by increasing the thickness of the polyester coating to slightly over 2 mils from approximately 1.3 mils for paperboard having similar surface characteristics. Although different polyester suppliers were utilized for these two tests, the effect of the source of polyester is discounted, particularly in comparing the results of samples 3 and 4 wherein coating of two different sources of polyester on similar surfaces yielded similar adhesion results. The foregoing test results are exemplary of data which indicates that, for polyester coating of a thickness of 1.5 mils or less, it is highly preferred that the Bendtsen roughness at 5 Kg. (TAPPI standard T-479) be at least 100 for the paperboard surface, and that the contamination level of the paperboard surface as measured by the foregoing iodine stain response test be approximately 25 or less. Under such board surface conditions, corona treatment above minimal levels may be expected to provide substantial enhancement of adhesion. It is also seen from this data that adequate adhesion may be obtained by increasing the thickness of the extrusion coating which apparently increases penetration of the hot melt into the paperboard. However, coating thickness greater than approximately 1.5 mils are undesirable since the stiffness of the coating interferes with die press forming of trays.
EXAMPLES 10-14
The following examples illustrate the effect of varying levels of corona treatment on board surfaces having the preferred surface characteristics. The paperboard of sample 5 above was utilized. The paperboard in all samples was run through the extrusion equipment at a rate of 175 ft. per minute and coextruded with Goodyear VPE 5792 polyethylene terephthalate at an extrusion temperature of 640° F., exiting from the extrusion die through an air gap of 41/2 inches before contact with the the paperboard surface. The chrome plated chill roll was maintained at a temperature of 60° F. and the nip pressure between the chill roll and the backup roll was 145 pli. The corona device was a Pillar model components AB 1326-3(-) and AB 1418-4(-).
With no corona treatment of the paperboard surface, the adhesion of the polyester to paperboard using an Instron tester at a 180° angle, 5 inches per minute, yielded adhesion fluctuating between 0 and approximately 90 grams per inch width. Samples 10-13 summarized in the table below were performed by first corona treating one surface of the paperboard to the energy density stated in the table, storing the paperboard for 10 days, and then extruding the polyester onto the treated surface thereof under the foregoing conditions. Sample 14 was obtained by running the paperboard at a rate of 175 ft. per minute continuously through the corona treater to the extrusion coating equipment.
Table 2______________________________________ Corona level Adhesion, Instron,Sample joules per polyester to board 180°Identification square inch angle, grams/25.4mm width______________________________________10 0.35 90-32011 0.74 90-32012 1.81 230-49013 5.05 230-45314 3.26 230-680______________________________________
Substantially enhanced adhesion is thus obtained with corona treatment levels as low as 0.35 joules per square inch, and without regard to whether the corona treatment is applied immediately before extrusion coating or after an intervening period of time. It is seen that optimum adhesion is obtained with corona treatment levels of approximately 2 to 5 joules per square inch. It is noted however, that enhancement of the adhesion does take place at corona levels as low as 0.35 joules per square inch.
EXAMPLE 15
The paperboard specified above in Examples 10-14 was passed through the corona treater at a corona level of approximately 5 joules per square inch at 175 ft. per minute and directly into the extrusion coating apparatus. A hot melt was prepared consisting of a uniform misture of 80% by weight Eastman 6857 polyethylene terephthalate and 20% by weight particulate Ampacet 11171 white concentrate pigment. Extrusion of the melt onto the paperboard was carried out in accordance with the process set forth for Examples 10-14, except that the melt temperature was lowered from 640° F. to 590° F. to form an acceptable melt curtain with the blend. The required lowering of the melting temperature was due to the presence of low density polyethylene present as a pigment carrier. The resulting coating had a thickness of approximately 1 mil and good adhesion, as measured on the Instron tester at 180°, of approximately 300 to 600 grams per inch adhesion. The uncoated side of the laminate was moistened with water and a wetting agent, wrapped in polyethylene and stored for 24 hours, and then formed on a die press into a tapered tray having a top flange, similar to that shown in FIG. 2. The tray was filled with 10 ounces of spagetti and beef sauce, and a film lid of 92 gauge polyester coated on one side with Adcote 1189-36 adhesive was applied and heat sealed to the top of the tray. The filled tray was covered with aluminum foil and frozen 3 days at 0° F. Upon removal from the freezer, the foil was removed and the tray was heated in an electric oven at 375° F. for 35 minutes. Upon removal from the oven, the temperature of the product was checked and the contents were removed from the tray. The tray was examined for adhesion of the coating and scorching of the board. No delamination of the coating from the board was observed. There was slight to moderate scorching of the flange but no scorching of the tray at the area in contact with the product, and no observable scorching of the board in the areas covered by the pigmented polyester coating.
It is understood that the invention is not confined to the particular embodiments described herein as illustrative, but embraces all such modified forms thereof which come within the scope of the following claims. | A coated paperboard product and a process for producing the same which includes corona discharge treatment of a paperboard surface and subsequent extrusion of molten polyester thereon. The resulting product has a very high degree of adhesion between the paperboard and polyester layers, and is capable of being utilized for forming pressed food trays which can be subjected to oven cooking temperatures. | 3 |
BACKGROUND OF THE INVENTION
The invention relates generally to solar energy collectors and more specifically to a solar energy collector of indeterminate length fabricated of flexible plastic materials for heating a flow of air.
The increasing cost of fossil and other expendable fuels has prompted extraordinary interest in the development and application of devices intended to recover solar energy. Embarking upon an examination of prior art solar collectors, one finds that it is convenient to divide the technology into two classifications: those utilizing a fluid for initial energy collection and those utilizing a gas. Solar energy collectors in the former group tend to be large, rigid, heavy and intended for permanent installation on roof tops and similar locations and are typically utilized to provide heat to permanent structures. Conversely, solar air heaters are more often lightweight, portable and utilized to provide supplemental heat to buildings or heat for such purposes as grain drying and the like. Due to the lack of relevance of fluid media solar collectors with regard to the instant device, only gaseous media fluid collectors will be discussed below.
U.S. Pat. No. 3,908,631 teaches an elongate collector having an air passageway which is insulated from the environment by a larger inflated chamber disposed directly thereabove. A pair of blowers provide air flow through both the primary air passageway and the insulating chamber and air exiting the chamber is mixed with air from the primary passageway. While the unit here described provides good heat recovery due to the layer of insulating air contained in the chamber, the structure itself incorporates many design features which result in an expensive and somewhat difficult to manufacture device.
U.S. Pat. No. 4,203,420 teaches a less complex solar energy collector which generally defines an elongate tube fabricated of plural layers of intimately contacting material having differing solar energy transmitting, insulating and absorbing characteristics. Since the layers of the solar collector tube are in contact, this configuration is obviously more compact than that described above. However, the assembly of material into this configuration is costly and furthermore the limited quantum of insulation affects the overall performance of this solar collector device.
U.S. Pat. Nos. 4,059,095 and 4,151,830 both disclose collectors of generally rectangular configuration wherein air or other heat recovery media flows through a serpentine path. At least one layer of plastic film or similar material confines at least one layer of static, insulating air over the serpentine collector path to provide improved energy retention in the collector and recovery by the flowing air. Here again, while both designs apparently provide good energy recovery performance, their construction entails numerous seams, seals, layers of material, and construction techniques which markedly increase the cost of the product.
U.S. Pat. No. 4,182,307 teaches another construction variation wherein an elongate structure having a serpentine flow path is disposed within a semi-circular insulating shroud. The serpentine collector is appropriately inclined to receive maximum energy from the sun. Again, the complexity of the device militates against its production at a price commensurate with its energy recovery capability. Furthermore, this solar collector is apparently several feet in height and therefore suggests that it not only may be adversely affected by wind but also may represent an overly attractive target for vandals.
From this review of the prior art, it can be seen that numerous devices, though available, each suffer from various shortcomings, most notably significant expense of materials and manufacture, especially when compared to their energy recovery capabilities and/or useful life.
SUMMARY OF THE INVENTION
The instant invention comprehends a solar air heater comprising a plurality of elongate, generally concentric cylinders. The outer or first cylinder and middle or second cylinder are interconnected by a suspension structure and cooperatively define an annular insulating region. Within the middle cylinder is disposed an inner cylinder defining a cylindrical flow region. The outer and middle cylinders as well as the suspension structure may be fabricated of a relatively thin polyethylene or vinyl sheet material whereas the inner cylinder is preferably constructed of somewhat thicker plastic material which is rendered self-supporting by the addition of a stiffening structure such as a helical wire such that it may withstand low negative pressures as well as positive pressures without collapsing or materially deforming. The outer cylinder may also include a portion, preferably approximately one-half its circumference which is white or silvered or aluminized in order to reflect solar energy toward the centrally disposed inner cylinder.
Construction of the device entails utilization of an indeterminate length of a thin, flexible plastic sheet material which may be folded upon itself and sealed to form the outer and middle cylinders as well as the suspension structure. As noted, the inner cylinder preferably is fabricated of more rigid material which inhibits collapse of the tube should air be drawn through the solar heater under negative pressure rather than forced through the heater under positive pressure as may be accomplished if desired. When utilized under positive pressure, a small bleed hole from the inner cylinder into the insulating annulus is utilized to inflate and maintain the insulating annulus in inflated condition. If utilized under negative pressure, a return line from the outlet of an associated blower into the insulating annulus provides the required flow of inflating air.
From the foregoing, it will be apparent that a solar energy collector according to the instant invention is readily manufactured of conventional materials and therefore is inexpensive and provides a high return on monies invented in a solar heater. The inner cylinder is preferably corrugated and thus may collapse to a small fraction of its length and since the outer and middle cylinders as well as the suspension structure are relatively lightweight, the heater may be collapsed so that it occupies a minimal volume when it is not installed and operating which facilitates shipment and storage thereof. Furthermore, simple, reusable splicing structures are utilized to permit ready assembly, disassembly and to facilitate increase in the energy collection capacity of the solar air heater simply by inserting additional collector sections.
Thus it is an object of the instant invention to provide a solar air heater of simple construction which is inexpensive to manufacture and provides excellent energy recovery.
It is a further object of the instant invention to provide a solar air heater having a design which is readily adaptable to compact storage and shipment.
It is a still further object of the instant invention to provide a solar air heater which may be readily assembled and installed, augmented to increase energy collection and disassembled and stored.
It is a still further object of the instant invention to provide a solar air heater which, when installed, is relatively compact and unobtrusive and therefore relatively immune to damage from strong winds and other sources.
It is a still further object of the instant invention to provide a solar air heater which may be utilized at both positive and negative pressures.
Further objects and advantages of the instant invention will become apparent by reference to the following description of the preferred embodiment and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is perspective view of the preferred embodiment of a solar air heater according to the instant invention;
FIG. 2 is a full, sectional view of a solar air heater according to the instant invention taken along line 2--2 of FIG. 1;
FIG. 3 is an enlarged, fragmentary sectional view of a solar air heater according to the instant invention taken along line 2--2 of FIG. 1;
FIG. 4 is a fragmentary sectional view of a solar air heater according to the instant invention taken along line 4--4 of FIG. 1;
FIG. 5 is a side elevational view in half section of a solar air heater according to the instant invention taken along line 5--5 of FIG. 1;
FIG. 6 is a perspective view of sheet material having a white or aluminzied region for a solar air heater according to the instant invention in preassembly configuration;
FIG. 7 is a perspective view of an alternate embodiment of the solar air heater according to the instant invention; and
FIG. 8 is a perspective view of a hold-down for use with the solar air heater according to the instant invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 and 5, a solar air heater assembly according to the instant invention is illustrated and generally designated by the reference numeral 10. The solar heater assembly 10 generally includes a blower assembly 12 for providing a flow of air and a collector assembly 14 to which air from the blower assembly 12 is supplied and heated. The blower assembly 12 includes a blower wheel 16 which may be of squirrel-cage construction of other wholly conventional design which is driven by a mechanically coupled prime mover such as an electric motor 18. The blower wheel 16 is rotatably disposed within a suitable housing 20 to which the motor 18 may be secured. The blower assembly 12 preferably includes suitable protective grillwork (not illustrated) over the inlet to the blower wheel 16 and protective guards (not illustrated) over the mechanical coupling between the motor 18 and blower wheel 16 as those skilled in the art will readily understand. A baffle plate 22 is secured across the outlet of the housing 20 and includes a circular collar 24 which defines an outlet opening 26 through which air under low static pressure exits the blower assembly 12.
Referring now to FIGS. 1, 2, and 3, the solar collector assembly 14 includes at least one and typically a plurality of elongate collector sections 30. The collector sections 30 may define any convenient flow path such as axial and U-shaped as illustrated in FIG. 1, semi-circular, or serpentine. It should be appreciated that such a choice is merely a matter of convenience and expedience depending upon the desired locations of the inlet and blower assembly 12 and outlet. Each collector section 30 of the solar collector assembly 14 includes an outer wall 32, a middle wall 34, and a hanger 36 which are all fabricated from a single panel 38 of plastic material of indeterminate length as illustrated in FIG. 7. The plastic panel 38 is preferably vinyl but may be any similar material having suitable characteristics of flexibility and transparency to solar energy. The panel 38 is folded to define the outer wall 32, the middle wall 34, and the hanger 36 as illustrated in FIGS. 2 and 3 and a four layer seam 40 is effected axially along the length of each section 30 by application of radio frequency or heat energy in accordance with conventional plastic sealing techniques. So configured, the panel 38 and the walls 32 and 34 define an outer, annular chamber 42 and a middle, generally circular chamber 44.
An axially extending collector tube 48 is received within the middle chamber 44 defined by the middle wall 34 and is slightly longer than the walls 32 and 34 of the collector section 30 with which it is associated. The collector tube 48 is suspended concentrically within the outer wall 32 by the hanger 36. The collector tube 48 is also preferably fabricated of vinyl or similar material but includes dispersed carbon black or a similar substance which renders the tube 48 highly absorbent of solar energy. In order to maintain the collector tube 48 in the desired circular configuration under all operating conditions, the wall of the collector tube 48 is corrugated as illustrated in FIGS. 4 and 5 and includes a helically wound strand of reinforcing wire 52 embedded therein. The collector tube 48 defines a flow region or passageway 54 which extends without interruption along the full axial length of the collector section 30.
Inasmuch as an approximately three inch layer of insulating air within the outer chamber 42 has been found to be a preferable compromise between excessive diameter of the collector assembly 14 and excessive heat loss, this three inch radial thickness of the outer chamber 42 is maintained throughout various designs having differing total diameters. Thus, the diameter of the outer wall 32 is approximately six inches greater than the diameter of the middle wall 34 and the collector tube 48. By way of further example, with an outside diameter of the outer wall 32 of fourteen inches, the mean diameter of the middle wall 34 and the collector tube 48 is preferably eight inches. With an outside diameter of the outer wall 32 of twenty inches, the mean diameter of the middle wall 34 and the collector tube 48 is again, approximately six inches smaller than the given diameter or fourteen inches.
The collector tube 48 preferably has a wall thickness of approximately 0.010 inches when the mean diameter of the collector tube 48 is in the range of from four inches to eight inches and has a thickness of approximately 0.016 inches if the collector tube 48 has a mean diameter of approximately twelve to fourteen inches. Clearly, these thicknesses may be varied somewhat from less than about 0.0075 inches to about 0.020 inches depending upon various characteristics of the collector assembly 14 and the material from which the tube 48 is fabricated. In order to provide sufficient rigidity, the diameter of the wire 52 is preferably in the range of from about 0.025 inches to about 0.035 inches. The wire 52 is preferably fabricated of carbon steel and has properties similar to piano wire or other relatively stiff wire.
Referring now to FIGS. 2 and 7, the plastic panel 38 which is folded and sealed to form the outer wall 32, middle wall 34, and hanger 36, is, in preassembly configuration, merely a panel 38 of sheet plastic material having a width slightly over five times the diameter of the completed collector assembly 14 and a length as determined by the required length of the section 30 to be assembled and thickness in the range of from about 3 to 8 mils. As noted previously, the plastic material is preferably vinyl having suitable flexibility and solar transparency. For increased solar collection efficiency, a portion of the outer wall 34 may be fabricated of a reflecting material such as white or aluminized vinyl. Aluminized vinyl reflects the sun's rays which have passed through the outer chamber 42 without striking the collector tube 48 and reflects them generally back toward the collector tube 48. An aluminized collector assembly 14 is fabricated by removing a panel equal to approximately 0.31 times the total width W of the plastic panel 38 and inserting and sealing with appropriate overlapping seams a panel 58 of an appropriate aluminized plastic material. For example, a solar collector section 30 having an outer wall 32 of diameter ten inches will require a plastic panel 38 having a total width W of approximately fifty-two inches. Of this fifty-two inches, approximately thirty-two inches will encompass that region of the outer wall 32, the areas designated by A, B and C in FIG. 7 and occupying approximately 0.06 W, 0.31 W, and 0.25 W, respectively. The remaining twenty inches defined generally by the region D and occupying approximately 0.038 W constitutes the hanger 36 and middle wall 34. Where W equals fifty-two inches, the width of the aluminized panel 58 will be approximately sixteen inches, fifty percent or 180° of the outer wall 32. It should be understood that the circumference or percentage of the aluminized panel 58 may be varied in response to various intended purposes of the collector assembly 14.
Referring now to FIGS. 1 and 4, a splice assembly 60 which facilitates interconnection of individual collector sections 30 of the collector assembly 14 is illustrated. The splice assembly 60 includes a cylindrical sleeve 62 having an outside diameter slightly larger than the inside diameter of the collector tube 48 which is inserted approximately half-way way into each open, adjacent end of the collector tubes 48 of aligned ends of sections 30 of a collector assembly 14. A pair of straps 64 such as cable ties or endless tension springs seat within the corrugations of the collector tubes 48 and secure the adjacent ends of the collector tubes 48 to the cylindrical sleeve 62. A similar splicing mechanism is utilized to interconnect the two adjacent ends of the outer wall 32. Here, a hoop or annulus 66 is received within the innermost one of a pair of outer walls 32 of the aligned ends of adjacent collector sections 30. The axis of the annulus 66 is disposed parallel to the axis of the collector sections 30. In FIG. 4, the inner one of the pair of outer walls 32 is illustrated on the right of the drawing. The other of the outer walls 32, generally illustrated on the left of the drawing, extends over the annulus 66 and inner one of the outer walls 32 from the opposite direction. A strap 68 such as a cable tie or similarly selectively securable device extends about the periphery of the annulus 66 to maintain the outer walls 32 in a secure, overlapped and sealed configuration as illustrated. The annulus 66 may be fabricated of any suitable material such as metal or plastic. It should be apparent that this splice assembly 60 is readily applied to the collector sections 30 and collector tubes 48, equally as readily removed, provides an airtight seal to the components of the collector assembly 14 and is reusable.
Referring now to FIGS. 1 and 5, a terminal assembly 70 of the collector assemblies 14 are illustrated. Each of the terminal assemblies 70 generally defines a frusto-conical plastic cap 72. The larger diameter end of the frusto-conical cap 72 is received within a splice assembly 60 described directly above. The smaller diameter end of the frusto-conical cap 72 tapers to a diameter substantially equal to the outside diameter of the collector tube 48 and includes a circular strap 74 such as a cable tie or endless tension spring which gathers and secures the end of the cap 72 to the collector tube 48 in an airtight manner. A similar strap 74 is utilized to secure the end of the collector tube 48 about the circular collar 24 of the blower assembly 12. Proximate the terminus of the collector tube 48 and disposed in its wall generally within that region defined by the plastic cap 72 is disposed an aperture 76. The aperture 76 provides communication between the passageway 54 defined by the collector tube 48 and the outer annular chamber 42 such that the outer walls 32 of the collector sections 30 are inflated when the blower assembly 12 is activated and air moves through the collector assembly 14. The diameter of the aperture 76 is preferably about 1 inch but the diameter may be varied between about 0.75 inches and 1.25 inches depending upon the total size of the collector assembly 14 and the desired speed of inflation.
With reference now to FIG. 6, an alternate embodiment of the solar air heater assembly 10' is illustrated. The alternate embodiment solar air heater 10' is substantially similar to the preferred embodiment assembly 10 with the exception that it includes a pair of collector assemblies 14' and that air is drawn through the collector assemblies 14' under negative pressure rather than being forced therethrough under positive pressure. Certain modifications to the equipment are therefore necessary. First of all, the housing 20' of the blower assembly 12' does not include the baffle 22 of the preferred embodiment but rather defines merely an open outlet 80 which is connected to the equipment or devices utilizing the air heated by the solar air heater 10'. The inlets of the blower assembly 12' are covered by circular baffle plates 82 having circular collars 84 which received terminal portions of the collector tubes 48' in a secure manner.
Likewise, the collector assemblies 14' of the alternate embodiment are similar though not identical to the collector assemblies 14 of the preferred embodiment. The collector sections 30' include the outer wall 32' the middle wall 34' and the hanger 36'. Likewise, a collector tube 48' extends from the blower assembly 12 along the full length of each collector assembly 14'. Adjacent the terminal portion of each of the collector tubes 48' is disposed a terminal assembly 70' which is similiar to the terminal assembly 70 of the preferred embodiment. The terminal assembly 70' is secured by suitable components of a splice assembly 60' which is identical to the splice assembly 60 illustrated in FIG. 4.
The significant difference between the alternate and preferred embodiments relates to the structure and method whereby the outer annular chamber 42' is inflated. Inasmuch as air passing through the passageway 54' is under negative pressure, it cannot be utilized to inflate the outer chamber 42'. Thus, air must be tapped from the exhaust of the blower assembly 12' and supplied to the chambers 42'. Such a supply of air under low positive pressure is provided by the tubes 86 which communicate between the outlet of the blower assembly 12' in the region of the outlet duct 80 and the chamber 42' in the region of the terminal assembly 70' adjacent the blower assembly 12'. It should also be noted that whereas the alternate embodiment assembly 10' may conveniently be utilized with a pair of collector assemblies 14', this is by no means necessary. Similarly, although the preferred embodiment assembly 10 has been illustrated with but a single flow path, parallel flow paths through parallel collector assemblies 14 may likewise be utilized.
Referring now to FIG. 8, a spring hold-down for use with either of the collector assemblies 14 or 14' is illustrated. A spring hold-down assembly 90 includes a relatively rigid preformed semi-circle 92 having a diameter equal to the diameter of the collector assembly and parallel tangentially disposed legs 94 having terminal spikes or similar structures 96 which retain the assembly 90 in soil or other displacable medium. Interconnecting the upper portions of the legs 94 is a selectively releasable tension spring 98. The assembly 90 may be disposed at any convenient location along the length of the collector assemblies and including coincident with one of the splice assemblies 60. The tension spring 98 is secured over the outer wall 32 of the collector section 30, thereby securing the collector assembly 14 against unwanted motion caused by wind or other external forces.
It will be appreciated that installation and operation of either the preferred or alternate embodiment of the solar air heater assembly 10 or 10' is both rapid and straightforward. The assemblies 10 or 10' may be assembled and installed as illustrated in FIGS. 1, 4, 5 and 6. That is, either one or more of the collector assemblies 14 may be utilized with either the positive pressure design of the preferred embodiment or the negative pressure design of the alternate embodiment. Similarly, the collector assemblies 14 may be oriented in parallel, serpentine, U-shaped or any other configuration which provides convenient locations of the inlets and outlets of the collector assemblies 14 or 14'. Subsequent to the application of power to the electric motor 18 or other prime mover, a flow of air will be established through the passageway 54 or 54' which will be heated by the available solar energy. The quantity of air through the collector assembly or assemblies 14 and 14' may be throttled by dampers or other suitable means (not illustrated) or the speed of the blower assembly 12 may be increased or decreased in order to control the temperature of the air delivered by the collector assembly 10 as those familiar with solar collectors will readily appreciate.
The foregoing disclosure is the best mode devised by the inventors for practicing this invention. It is apparent, however, the devices incorporating modifications and variations will be obvious to one skilled in the art of solar collector devices. Inasmuch as the foregoing disclosure is intended to enable one skilled in the pertinent art to practice the instant invention, it should not be construed to be limited thereby but should be construed to include such aforementioned obvious variations and be limited only by the spirit and scope of the following claims. | A solar air heater comprises a plurality of elongate concentric flexible cylinders which define an outer annular insulating region, an inner cylindrical flow region and a positioning structure therefore. A plastic panel of indeterminate length may be folded upon itself and sealed to form the outer wall of the insulating annulus, the positioning structure and a middle wall. The cylindrical flow region is defined by a self-supporting tube which is inserted into the positioning structure and middle wall. Air flowing through the self-supporting tube is heated by available solar energy and the outer region, inflated by air at a pressure slightly above atmospheric pressure, acts as an insulator. | 5 |
FIELD OF THE INVENTION
[0001] This invention refers to an air to air refueling system and, more specifically, to its electrical system.
BACKGROUND
[0002] One known system for conducting air to air refueling operations is based on the use of a refueling device with a rigid mast for connecting the tanker aircraft to the receiver aircraft in flight, which is basically a telescoping or extendable boom joined to the underside of the tanker aircraft by means of an articulating element that enables the flow of fuel from the tanker aircraft to the receiver aircraft. In the tanker aircraft the operator visually controls the all of the steps and procedures to carry out a secure refueling operation by maneuvering the beam until it physically connects to the receptacle of the receiver aircraft.
[0003] Another known system for conducting air to air refueling operations is a refueling device with a flexible hose and a drogue that is dragged from the tanker aircraft. The basked is an accessory joined to the hose by means of a valve for the purpose of stabilizing it during flight and providing a channel that assists in inserting the probe of the receiver aircraft into the hose. The hose is connected to a drum unit so that when the hose is not in use it is completely reeled into the drum unit. The receiver aircraft has a probe which is a rigid arm situated on the fuselage or nose of the aircraft. The probe is normally retracted when it is not in use, especially in high velocity aircraft.
[0004] A tanker aircraft can be equipped with all or some of the following devices:
[0005] Two hose and drogue refueling devices housed in a gondola suspended underneath the wings of the tanker aircraft.
A hose and drogue refueling device located in the central fuselage. A rigid beam refueling device located in the tail of the tanker aircraft.
[0008] During operations these devices require important power outlays that must covered by the power systems of the tanker aircraft, thus reducing its availability for the rest of the devices in the tanker aircraft, and, if the situation arises, overloading the capacity of the power generators of the base aircraft, be it hydraulic power or electrical power.
[0009] In the case of hose and drogue refueling systems, the components which consume most energy are the fuel pump and the device for moving the winding drum onto which the hose is reeled. In the known systems, when they are in position in the gondola the fuel pump is usually dragged by a wind turbine, such as a RAT (“Ram Air Turbine”) the speed of which is controlled by variations of the propeller pace. Thus little energy is required from the tanker aircraft (the only need being that of the actuator for the propeller speed controller of the wind turbine). In the case of systems located underneath the central fuselage, the fuel pump is generally dragged by a hydraulic motor fed from the hydraulic system of the tanker aircraft.
[0010] The device for moving the winding drum is fed either by the hydraulic system of the tanker aircraft or by the electrical system of the tanker aircraft.
[0011] In the case of refueling systems by a rigid mast, the components demanding most energy are the actuation devices of the airfoils for controlling the flight, the device for moving the telescoping boom and the device for hoisting the mast, which can be fed from the hydraulic system or electrical system of the tanker aircraft.
[0012] To cover the added demand for energy of all of the refueling devices during an air to air refueling mission, the hydraulic and/or electric power systems must have sufficient capacity to cover both the demands of said refueling devices and the demands pertaining to the tanker aircraft: flight controls, avionics, armament, radar, etc., which implies oversizing its electrical system, of which there is already an observable growth tendency due to the substitution of hydraulic devices for electrical devices in aircraft.
[0013] This invention is oriented towards a solution to this problem.
SUMMARY OF THE INVENTION
[0014] One object of the present invention is to provide an air to air refueling system with an autonomous electrical system and a method for operating the same.
[0015] Another object of the present invention is to provide an air to air refueling system with the capacity of reusing the power generated during a refueling mission and an operating method of the same.
[0016] Another object of the present invention is to provide an air to air refueling system that facilitates the conversion of a commercial aircraft into a tanker aircraft.
[0017] In a first aspect, these and other objectives are obtained with a refueling system that comprises at least two hose and drogue refueling devices housed in gondolas deployed underneath the wings of the aircraft, each refueling devices comprising a plurality of components actuated by electrical actuators, in which its electrical system is formed by two subsystems comprising each one of them: a) an electric generator actuated by a wind turbine located in one of said hose and drogue refueling devices; b) an energy storage device; c) a connection to the electrical system of the aircraft; d) a control device equipped with means for ensuring the generation and storage of the power needed to fulfill the electrical demands of the refueling system without tapping into the electrical system of the aircraft, except in the case that the stored power in said energy storing device drops below a preset value.
[0018] In embodiments of the present invention, said hose and drogue refueling devices include at least the following electrical actuators: the velocity control actuator for the propeller of the wind turbine, the actuator for the winding drum of the hose and the actuator for the fuel pump. Thus electrical actuators are used for the main components of hose and drogue refueling devices.
[0019] In embodiments of the present invention, the refueling system also comprises a third hose and drogue refueling device in the central fuselage that includes at least the actuator for the winding drum of the hose and the actuator for the fuel pump, and/or a refueling device with a rigid beam, which includes at least the following electrical actuators: the actuator for the hoisting drum of the beam, the actuator for moving the telescoping boom of the beam and the actuators for the airfoils of the mast. In this manner a refueling system is obtained that is equipped with an electrical system which, to a large extent, is autonomous with up to four refueling devices for increasing the refueling capacity of the tanker aircraft.
[0020] In embodiments of the present invention, said energy storage device comprises one or more of the following elements or a combination of them: a battery, preferably lithium, an ultracapacitor, and a flywheel. In this way a storage device is obtained with sufficient capacity for providing an almost complete autonomy to the electrical system with regard to the electrical system of the tanker aircraft.
[0021] In embodiments of the present invention: the voltage of the distribution network of said electrical subsystems is 270 Vdc; the generators are AC generators with a preferred voltage of between 2 and 10 Kw, and said electrical subsystems include rectifiers associated to them; said connection to the electrical system of the aircraft is equipped to provide electric power at a voltage of 270 Vdc. In this manner an electrical system is achieved that is adapted to the needs of an onboard aircraft system, especially in regard to the reduction of cabling and weight.
[0022] In a second aspect, the previously mentioned objectives are achieved by means of a method for administrating the electrical energy flow in an air to air refueling system installed in a tanker aircraft, the refueling system comprising at least two hose and drogue refueling devices housed in gondolas deployed underneath the wings, each refueling device comprising a plurality of components actuated by electrical actuators, comprising the tanker aircraft an electrical system with means for generating electric power, which comprises the steps of: a) using the electrical system of the refueling system that comprises two electric generators actuated by wind turbines and two storage devices before commencing a refueling mission so as to charge said storage devices with the energy generated by said electric generators; b) administrating the power flow during a refueling mission using said electrical generators and said electrical energy storage devices to provide the energy required by said electrical actuators when they act as power consumers and storing said storing devices the electric power provided by said electrical actuators when they act as power generators.
[0023] In embodiments of the present invention in said steps a) and b), energy generated by the electrical system of the tanker aircraft is also used if it becomes necessary to maintain the energy stored in said energy storage device above a preset value, thus the supplying of power from the electrical system of the aircraft to the electrical system of the refueling system at a constant present voltage is produced. In this way the optimization of the respective systems of the tanker aircraft and the refueling system is obtained.
[0024] In the embodiments of the present invention the method is applicable to systems that comprise the same type of refueling devices mentioned previously. In a third aspect, the mentioned previously objectives are obtained with a method of converting a commercial aircraft into a tanker aircraft that comprises the steps of:
installing in the commercial aircraft an air to air refueling system with the features mentioned previously; connecting the electrical system of the refueling system to the electrical system of the aircraft in such a way that the first is able to receive from the second, at a constant preset voltage, the power needed to maintain the stored energy in its energy storage devices above a preset value in the course of a refueling mission.
[0027] Other features and advantages of the present invention will be disclosed in the detailed description which follows from an illustrative embodiment of its object in relation to the drawing that accompanies it.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a block diagram of the electrical system of an air to air refueling system connected to the electrical system of the tanker aircraft.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] In the preferred embodiment that we are going to describe, the refueling system is comprised by all of the previously mentioned refueling devices, namely, two hose and drogue devices in gondolas suspended under the wings of the tanker aircraft, a hose and drogue device located on the underside of the central fuselage of the tanker aircraft, and a rigid beam device located in the tail of the tanker aircraft.
[0030] In a system of this type the main features of the operation of the refueling devices and their power balance are the following:
The operation on land of the refueling devices for maintenance and autodiagnostic activities, for example, which requires power independent of the aircraft, either hydraulic or electric, as the case may be. The hose and drogue devices housed in the gondolas generally are operated simultaneously. The rigid beam device is operated in an independent manner, hence, without coinciding with the hose and drogue devices. In the hose and drogue devices, during deployment of the same the aerodynamic forces on the drogue on the end of the hose permanently pull at it, for which the control system for moving the drum behaves like a power generator. The power generated dissipates internally in the form of heat. In hose and drogue devices, during contact with a receiver aircraft there are periods of net power consumption and periods of net power generation, depending on the movements of the receiver aircraft. When the receiver aircraft separates from the tanker aircraft energy is generated, whereas, when it approaches the device consumes power to reel in the hose. As in the previous case, the energy generated dissipates internally in the form of heat. In hose and drogue devices power is consumed during the reeling in of the hose upon completing the refueling. In the rigid mast device, during deployment of the same the hoisting system sustains the weight of the mast, and thus behaves as a generator. The energy generated dissipates internally in the form of heat. The control system of the telescoping beam also behaves as a generator when the beam is extended with the mast deployed in angles below horizontal and during braking in the final positions of extension. The energy generated likewise dissipates internally in the form of heat. In the rigid mast device, during contact with the receiver aircraft, in the actuator for the telescoping beam there are periods of net power consumption with periods of net power generation, depending on the movement of the receiver aircraft. As in the previous case, the energy generated is dissipated internally in the form of heat. In the rigid mast device, following disconnection there are punctual operations of very brief duration, such as emergency retraction (retraction of the telescoping beam at a speed of 3 m/s for two seconds) in which the actuator for the telescoping beam requires a peak in power consumption on the order of up to 25 Kw, which could require the use of the overcharge capacity of the power generators of the tanker aircraft. In the rigid mast device, when hoisting the mast the hoisting actuator consumes power from the tanker aircraft. In the rigid mast device, both during deployment, in the free flight phase, as well as during coupled flight with a receiver aircraft, the actuator for the aerodynamic surfaces for flight control alternates periods of consumption with generation of energy, depending on the direction of the movement of the surfaces with respect of the aerodynamic loads and inertia. The energy generated in dissipated internally in the form of heat.
[0041] That said, we will now review in greater detail the refueling system in accordance with the invention:
It is equipped with its own sources for generating power and electric power storage, and so does not need, as occurs in the earlier art, the electrical system of the tanker aircraft to supply all of the electric power it needs, which requires sizing the same to be able to handle the power spikes of the refueling devices which operate simultaneously. It is equipped with storage capacity for the power generated by the refueling devices, thus it does not require a large power dissipation capacity for administering the power generated during refueling operations. It is connected to the electrical system of the tanker aircraft so as to receive electric power only in those momentary situations in which the demand of the refueling systems is not covered by the generating capacity and stored power.
[0045] Following FIG. 1 below we will describe the main components of the refueling electrical system in accordance with the invention.
[0046] The system is formed by two symmetric subsystems, each one of them fed by half of the refueling devices, that is, hose and drogue device 3 , 5 located underneath the wings, hose and drogue device 7 located in the central fuselage and the device for rigid mast 9 , each one of said elements equipped with the following elements:
[0047] An AC generator 11 , with a power output of approximately 5 Kw, generally with a variable frequency, integrated in one of the gondolas which house a hose and drogue device underneath the wings that is dragged by wind turbine 25 of the type currently used for actuating the fuel pump.
A rectifier 13 associated to AC generator 11 and sized in accordance with its capacity for converting the generated AC electricity into 270 Vdc electricity for its distribution in the refueling electrical system. A rectifier 15 that makes possible the connection to the AC electrical system of the tanker aircraft, transforming the energy produced by an AC generator 17 into 270 Vdc for its distribution in the refueling electrical system. This rectifier 15 is appropriately sized only for distributing the needed electrical power to momentarily supplement the capacity of the refueling electrical system. An electric power storage device 19 which may be a set of batteries, preferably lithium, a set ultracapacitors, flywheel or a combination thereof. An energy flow administrating element 21 between the different branches of the system and for electrical protection and isolation in the event of failures. The diverse actuators using DC using 270 Vdc electrical feeds, in which half of each one is fed by an electrical subsystem (either having a twin motor or two independent motors), among which there may be included: Actuator 23 for controlling the propeller speed of wind turbine 25 ; Actuator 27 for hose winding drum 27 of the hose and drogue device housed in a gondola suspended underneath the wing; Actuator 35 for hose winding drum 37 of the hose and drogue device located in the central fuselage; Actuator 38 for the fuel pump of a hose and drogue device located in the central fuselage. Actuator 39 for hoisting drum 41 of the rigid mast device; Actuator 43 for telescoping beam 45 of the rigid mast device; Actuators 47 , 51 for flight airfoils 49 , 53 for the rigid mast device;
[0060] Said subsystems likewise comprise auxiliary and control elements (not depicted in FIG. 1 for the sake of simplicity) and, in particular, electronic control units associated to each one of said actuators.
[0061] Following the description of the system in accordance with the invention, we now move on to describe the operating method of the same.
[0062] A modern tanker aircraft carries out both transport missions in which the refueling system is deactivated, as well as refueling missions.
[0063] During transport missions and during approach phases in the refueling zone of refueling missions, storage devices 19 of the electrical system (batteries, condensers, flywheels or a combination thereof) are recharged by the power provided by generators 11 through their rectifiers 13 or, as the case may be, by the electrical system of the tanker aircraft through rectifiers 15 , with a low charging power so as to avoid causing an important consumption in the base aircraft. The goal is to reach approximately 70% to 80% power storage of the installed capacity of storage devices 19 at the start of the refueling mission
[0064] When the refueling devices are activated generators 11 are also enabled (if they were not already), which enables autonomous supplying of electrical power for operating the refueling devices.
[0065] While operating each actuator for a refueling device acts in consecutive moments as a power consumer or generator. The average net power balance during the refueling mission is the net power consumption (with an average consumption of around 7-10 Kw), which is covered by the capacity of generators 11 . The power momentarily generated by the actuators that behave like generators is used by other actuators that behave like consumers in this moment, in such a way that the total electrical demand of the subsystem is only the difference. In the event of excess power generation, the overflow energy is stored in storage devices 19 .
[0066] When net consumption exceeds the generating capacity of generators 11 , energy stored in storage devices 19 is used. If the situation of high power consumption is maintained, such that the stored power is reduced to below a minimum threshold, power from the electrical system of the tanker aircraft is used to maintain a constant level of stored power in storage devices 19 . In this way the power demand placed on the tanker aircraft will only be what is needed to maintain the load in storage devices 19 , thus it would only be the average of the excess power required above the generating capacity of generators 11 . Furthermore, this demand for power is averaged over the elapsed time of the mission, in such a way that if the situation arises a constant power need, without spikes, would be required from the tanker aircraft for maintaining a constant current load to storage devices 19 . This process is administered by rectifiers 15 associated to the electrical system of the tanker aircraft and by administrating elements 21 . The power consumption spikes required for the actuators are supplied by storage devices 19 . Thus, independently of the ongoing refueling operation, the electrical system of the tanker aircraft is only required to supply a constant low power flow that does not represent an excessive load with respect to the installed capacity of the aircraft.
[0067] In the event that it is not possible to use power from the tanker aircraft, storage devices 19 allow supplying power to the refueling devices and maintaining operations without degrading performance for a duration in accordance with their storage capacity. Storage devices 19 also enable operations on land of the refueling devices, without the need of the base aircraft providing electrical power, which is an additional advantage with respect of maintenance, auto-diagnostics and operations in unprepared air bases.
[0068] Although the instant invention has been disclosed entirely in connection with the preferred embodiments, it is clear that those modifications that are within its scope may be introduced, and that the invention should not be considered limited by the previous embodiments, but rather to the content of the following claims. | A system for air to air refueling with an autonomous electrical system, comprising at least two hose and drogue devices ( 3, 5 ) housed in gondolas located underneath the wings of the aircraft, each refueling device comprising a plurality of components actuated by electrical actuators and its electrical system that is formed by two subsystems, each one of them comprising: a) Electric generator ( 11 ) actuated by a wind turbine ( 25 ) located in one of said gondolas; b) Energy storage device ( 19 ); c) Connection to the aircraft electrical system ( 15, 17 ); d) administrating device ( 21 ) equipped with means for ensuring the generation and storage of the energy required for responding to the electrical needs of the refueling system without recurring to the electrical system of the aircraft except in the event that the energy stored in said accumulation device ( 19 ) falls below a preset value. | 1 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part of U.S. patent application Ser. No. 60,626 filed June 11, 1987 and entitled FUEL BURNING APPLIANCE INCORPORATING CATALYTIC COMBUSTOR, now abandoned.
This invention relates to wood burning stoves and heaters and improvements therein which maximize heating efficiency while reducing pollutants in the exhaust gases.
In recent years, due primarily to the energy crisis, wood burning stoves have enjoyed an ever-increasing popularity and public acceptance. The ultimate objective in stoves of this type is to achieve as complete combustion as possible of the combustion gases, since with more efficient combustion, burn time can be increased because it is possible to slow the fire down and still obtain the desired heat transfer for maximum comfort. However, most existing stoves of this type, i.e., airtight wood burning stoves, have a combustion efficiency somewhere in the range of fifty to sixty percent, primarily due to the fact that the ignition point of combustion gases is in the general range of 1300° F., whereas the temperatures generated in stoves of this type are usually in the range of 500° and 900° F. Thus, efficient combustion of these combustion gases has been difficult, if not impossible, to achieve, resulting in lower combustion efficiency, which in turn results in creosote buildup in the chimney or flue, which buildup frequently results in chimney fires. Also, reduced combustion efficiency results in undesirable smoke pollution.
Various arrangements have been employed in the prior art in which catalytic converters or combustors have been employed to oxidize flue gases and recover the additional heat associated therewith prior to discharge from the chimney. Specifically, by causing the combustion gases to flow through a catalytic combustor before reaching the exhaust duct or flue of the stove, the ignition point of the escaping combustion gases is lowered to the general range of 350°-500° F., thus resulting in almost complete afterburn of these gases in the normal range of operating temperatures in stoves of this type. This results in combustion efficiency in the general range of ninety percent, or in other words, an efficiency of approximately thirty-five percent more than that achieved by traditional woodburning stoves. This increased efficiency means little or no pollution will enter the atmosphere because the smoke, a normal by-product of conventional wood stoves is actually chemically burned, leaving a harmless vapor and a small ash in its place. In addition, as a result of the almost perfect combustion that takes place, there is virtually no creosote buildup in the chimney, thus greatly reducing chimney fire hazards and at the same time, reducing chimney maintenance. Furthermore, peak performance can be obtained even with the use of soft and unseasoned wood and burn time can be increased because it is possible to slow the fire down and still maintain almost perfect combustion while transferring heat temperatures necessary for maximum comfort.
While the use of such catalytic combustor units has proved useful in eliminating substantial quantities of creosote and in increasing the efficiency of the wood burning stove, there have previously been a number of limitations in the use of such catalytic combustors. For example, such catalytic combustor units over a period of operation become sites for the deposits of carbon ash residue and creosote residue. The carbon ash residue may be deposited on the combustor in such a manner that the combustor element is clogged and eventually becomes inoperative. The creosote residue may also clog the catalytic combustor over a period of time and prevent or interfere with proper functioning of the combustor unit.
Another problem associated with the incorporation of the catalytic combustor in a stove or heater is that while the combustor functions well in the intended manner once the fire is established, its presence in the airflow path is not always advantageous. During the starting of the fire, before the heated flue gases have developed a strong updraft, the combustor impedes airflow and interferes with starting. Also, when the door of the stove is opened to add fuel or to attend to the fire bed, the air restriction caused by the combustor sometimes causes smoke and gases to be exhausted into the room.
The successful implementation of a stove or heater incorporating a catalytic combustor is, therefore, dependent upon the realization of satisfactory solutions to a number of problems that have not been simultaneously addressed or effectively resolved in the prior art.
PRIOR ART
Various devices have been developed to reclaim heat from the exhaust pipe of a fuel burning appliance (stove, heater, etc.). While these devices do operate to reclaim additional heat, a common problem is encountered where the structure of the device upsets the draft required to maintain combustion. The result is that both back puffing of smoke and difficulty in developing a proper rate of combustion may ensue. Those devices which have addressed the problem of maintaining an adequate draft throughout the burning cycle have resulted in unduly complex mechanisms.
U.S. Pat. No. 1,280,235 discloses a heating stove comprising a preheater and first and second combustion chambers. Inlet air is preheated before entering the first combustion chamber in which the primary fuel is burned. Air and combustion products pass from the first combustion chamber to the second combustion chamber into which additional atmospheric air is admitted to promote further combustion of gases and soot prior to discharge into the stove pipe.
U.S. Pat. No. 4,336,836 discloses an apparatus mounted in the flue of a combustion fuel heating unit for reclaiming heat from the discharge gases, which reclaimer exposes the discharge gas flow to an increased surface area of the flue to absorb a portion of the heat energy otherwise lost in the exhaust gas flow.
U.S. Pat. No. 4,373,507 discloses a wood burning stove that employs a catalytic converter to achieve increased combustion efficiency. A manually controlled damper causes the converter to be bypassed before the door of the stove can be opened.
U.S. Pat. No. 4,466,421 discloses an afterburner intended for installation in the flue of an existing stove. The afterburner incorporates a catalytic combustor which may be moved forward manually to remove it from the path of the flue gases.
U.S. Pat. No. 4,549,524 discloses an apparatus for supporting a catalytic converter as a means for burning exhaust gases from a heating stove. The apparatus incorporates a means for bypassing the converter when necessary, as during the starting of the fire in the primary combustion chamber.
U.S. Pat. No. 4,550,668 discloses a combustor unit for a wood burning stove. The unit comprises a T-shaped flue assembly incorporating a catalytic converter that can be tilted out of the way of the exhaust gas stream into an access passageway through which it is removable and in which it may be cleaned without removal.
Each of the above described prior art devices or apparatus addresses one or the other of the various problems associated with the attainment of increased heating effectiveness or efficiency or with the removal of pollutants from the flue gases. What is needed, however, is an improved stove or heater that incorporates catalytic combustors in a manner that results in optimum automatic operation under all conditions with the necessary controls and access conveniently and inexpensively provided.
The present invention is directed toward the provision of an improved heater or stove in which the total arrangement of the stove is optimized for the simultaneous solution of all the problems that have been related.
SUMMARY OF THE INVENTION
In accordance with the invention claimed, a new and improved fuel burning appliance is provided in which the total configuration of the appliance is optimized for the achievement of maximum heating efficiency and pollutant removal. Pollutant removal is achieved through the incorporation of a catalytic combustor in a manner that does not interfere with other aspects of operation.
It is, therefore, one object of the present invention to provide an improved fuel burning appliance.
Another object of this invention is to provide as an element of such an appliance an improved heat reclaimer and catalytic combustor which substantially increases oxidation or burning of carbon monoxide and other fuel volatiles at temperatures that otherwise would not allow oxidation to occur.
A further object of this invention is to incorporate in such an appliance an improved heat reclaimer and catalytic combustor that substantially reduces creosote and air pollutants in the exhaust gases of a wood burning appliance.
A still further object of this invention is to incorporate such a heat reclaimer and catalytic combustor in such an appliance in a manner which permits the maintenance of the necessary draft to fire the appliance for the burning of wood or other fuels.
A still further object of this invention is to incorporate in such an appliance a holder for the catalytic combustor that is simple in form, inexpensive in construction and fully functional in the sense that it allows for rotation of the combustor to a bypass position and convenient cleaning in the bypass position or removal for cleaning.
A still further object of this invention is to incorporate in such an improved burning appliance a heat reclaimer for extraction of the heat of combustion produced in the catalytic combustor.
A still further object of this invention is to provide an improved fuel burning appliance employing at least a pair of catalytic combustors spaced from each other in the path of movement of the combustion gases to reduce pollutants in the exhaust gases.
A still further object of this invention is to provide an improved fuel burning appliance employing at least a pair of catalytic combustors spacedly positioned in the path of movement of the combustion gases, the second one of which functions to oxidize flue gases and recover additional heat associated therewith if the first catalytic combustor is overloaded, thereby failing to completely oxidize and burn all of the combustion gases passing therethrough. The use of two combustors creates automatic flow features with no manual controls required.
A still further object of this invention is to provide two combustors in series with temperature or heat magnification.
A still further object of this invention is to provide a plurality of spaced catalytic combustors in a fuel burning appliance, with one combustor mounted on an edge of a smoke baffle mounted above the fire bed.
A still further object of this invention is to provide in such an improved burning appliance means for augmenting the air supply, thereby offsetting any restriction of airflow resulting from the incorporation of the catalytic combustor.
A still further object of this invention is to provide a triangular-shaped burning appliance that enhances heat radiation at the front of the appliance. A triangular configuration is markedly better than a trapezoidal shape used on some stoves.
A still further object of this invention is to provide such an improved fuel burning appliance in an inexpensive form that is equally adaptable to stoves or fireplaces.
Further objects and advantages of the invention will become apparent as the following description proceeds and the features of novelty which characterize the invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more readily described with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of one embodiment of the improved fuel burning appliance or stove of the invention;
FIG. 2 is a front view of the lower portion of the appliance of FIG. 1 with portions of the firebox cut away to show the form and placement of an air augmentation means incorporated in the appliance;
FIG. 3 is a side view of the lower portion of the appliance of FIG. 1, again with portions of the firebox cut away to show the air augmentation means;
FIG. 4 is a cross-sectional view of FIG. 1 taken along the line 4--4;
FIG. 5 is an exploded perspective view of the catalytic combustor and its associated combustor holder;
FIG. 6 is an enlarged perspective view showing details of the combustor construction as seen at area 6 of FIG. 5;
FIG. 7 is an enlarged partially cut away view of the assembled combustor holder of FIG. 5;
FIG. 8 is a perspective view of a further embodiment of the fuel burning appliance or stove shown in FIG. 1, employing a pair of catalytic combustors spaced from each other in the path of movement of the combustion gases and an air vent above the door of the stove for controlled air movement in the stove;
FIG. 9 is a cross-sectional view of FIG. 8 taken along the line 9--9;
FIG. 10 is an enlarged view of the circled area identified by the reference character 10 in FIG. 8;
FIG. 11 is a cross-sectional view of FIG. 8 taken along the line 11--11;
FIG. 12 is an enlarged perspective view of the air supplement manifold shown in FIG. 8;
FIG. 13 is a cross-sectional view of FIG. 10 taken along the line 13--13;
FIG. 14 is a cross-sectional view of FIG. 11 taken along the line 14--14; and
FIG. 15 is a cross-sectional view of FIG. 11 taken along the line 15--15.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring more particularly to the drawings by characters of reference, FIGS. 1-3 disclose a fuel burning appliance or stove 10 comprising a firebox 11, an air augmenter 12, a catalytic combustor 13, a heat exchanger 14, a damper 15 and a flue or chimney 16.
While appliance 10 is not limited to use for burning wood, the immediate object of the invention is to provide a stove that is ideally suited, first of all, for use as a wood burning stove.
Firebox 11 is a relatively conventional heater or stove, ordinarily made of iron or steel, except that its general shape or configuration as viewed from above is preferably triangular rather than rectangular. The triangular shape is advantageous for a number of reasons. As shown in FIG. 1, one side of the triangular configuration constitutes the front of the firebox while the flue is positioned over the opposite corner at the rear of the firebox. The firebox thus has its widest dimension at the front, and it can thus accommodate a wide grate and relatively long pieces of firewood at the front where the fuel is normally loaded. A second advantage of the triangular configuration is that the wall of the firebox that faces to the front constitutes approximately one-third of the total vertical radiating surface of the firebox as compared with one-fourth of the total for the front face of a square or slightly rectangular firebox. The triangular configuration also allows for a wider door, improved air entry from the front and a good internal airflow pattern. When a cooking surface is to be provided on top of the firebox, the enlarged forward dimension provides increased cooking space at the front of the stove. In addition, if a fan is positioned behind the stove, the air from the fan will be split by the rearward apex and will flow past both sides of the firebox to distribute heat effectively throughout the room being heated.
Air augmenter 12 comprises a hollow pipe structure including a horizontal pipe member 17 supported by a vertical pipe member 18. Horizontal pipe member 17 is perforated along its sides to prevent plugging by foreign material. Air introduced into member 18 from out-of-doors flows into and out of member 17 via perforations 19. Due to its position below catalytic combustor 13, heated air supplied by augmenter 12 to combustor 13 enhances its performance.
As shown in the drawings, the catalytic combustor 13 is connected at its inlet end 21 to one section of a flue 22 leading from firebox 11 and at its outlet end 23 to the inlet 24 of an expansion section of heat exchanger 14. The outlet section 25 of heat exchanger 14 is connected to the flue or chimney 16 for exhausting combustion gases of stove 10 to atmosphere.
The expansion section 26 of the heat exchanger 14 has a circumference which gradually increases in the direction of gas flow. It is connected at its inlet 24 to the outlet 23 of combustor 13 and at its expanded end 27 to an idler section 28 of exchanger 14. The expansion section 26 encloses flow splitter plates 29 which are radially arranged about the axis of expansion section 26, as shown in the cross-sectional view of FIG. 4. A reduction section 31 of exchanger 14 is connected to idler section 28 and to outlet section 25 which in turn is connected to one section of the flue or chimney 16.
The catalytic combustor 13 comprises a catalytic element 32 shown in FIGS. 5 and 6 which, when inserted properly into a fuel burning stove or heater, will "burn" the smoke, carbon monoxide and particulates which are not burned by the fire in firebox 11 or combustor 13A. It is an "after burner" which, because of a catalyst, chemically breaks down smoke, carbon monoxide and particulates into substances that are burned at a low temperature. The combustor element 32 is in the form of a short cylinder or disc having a honeycomb structure with axial openings through which the flue gases are passed. The relatively large surface area produced by the honeycomb structure enhances the operating efficiency of the combustor.
Catalytic combustors can be made of ceramic or metal and may use different kinds of catalysts which are applied to the ceramic or metal by different methods and in different quantities and they are manufactured in various shapes and sizes.
The size and shape of the catalytic combustor for a given heater is determined by the size of the firebox and the space available for its installation. Use of a plurality of combustors increases the total combustion surface available.
The most substantial difference, however, is the "substrate" material (the material on which the catalyst is applied). Two basic substrates are used, namely metal or ceramics.
Metal is generally not an acceptable substrate for catalysts due to two reasons:
a. The expansion of the metal substrate is different than the expansion of the catalyst. Therefore, as the combustor reaches the very high temperatures it is subjected to, the metal substrate begins to expand--the catalyst metals are expanding at a different rate--and the catalyst may fall off.
b. Metal is not porous enough to sustain enough catalyst to perform. In other words, enough catalyst may not stick to the metal to enable sufficient catalytic activity.
The best catalyst substrate material is ceramic. Most ceramic substrates are made from cordierite which is a high temperature resistant ceramic which does not have sufficient thermal shock resistance to withstand the wood stove environment. After a period of use, ranging anywhere from one month to one year, cordierite combustors may begin to crack and break or begin crumbling to the point where large sections of the combustor are gone. Technical Glass Products of Kirkland, Washington, manufactures and sells a honeycomb type ceramic which is a combination of calcium aluminate and titanium oxide. The combination of these two ceramics make a substrate with a high surface area, high temperature resistance and excellent thermal shock resistance. It works better, and lasts longer than the prior art.
The basic catalysts used for wood smoke are platinum and palladium, although other more rare metals may be used. With most combustors, the grams of platinum and/or palladium are applied to the ceramic or metal substrate with a "washcoat". In other words, the ceramic or metal substrate is dipped into a liquid which clings to the substrate and the catalyst is applied to the washcoat. The washcoat sticks to the ceramic, and the catalyst sticks to the washcoat. While this method works well in the beginning, as the catalytic combustor is used at high temperatures, the washcoat may begin to "spall" or pull away from the ceramic and fall off, taking the catalyst with it. Eventually, all you may have is a ceramic substrate with no catalyst. The Technical Glass product which is covered by U.S. Pat. No. 4,350,613 is "impregnated" into the ceramic--actually placed in the ceramic material as it is formed. The benefits of this are obvious--you always maintain the catalyst--it does not fall off. The description of U.S. Pat. No. 4,350,613 is incorporated herein by reference.
It is important to remember when operating a catalytic combustor equipped device, to make sure you have achieved catalytic "light-off" before you place the unit into the catalytic operational mode. Light-off simply means that you have achieved enough temperature within your unit to start the catalytic combustor operating. Catalytic burning, like all types of burning, requires three essential elements: fuel, oxygen and temperature. The "smoke" is the fuel. The catalytic element disclosed is designed so that it will have sufficient oxygen, but the operator must assure that the required temperature is achieved. The temperature needed to begin catalytic activity is generally 350°-500° F. This is a temperature that is easily achieved when you build a fresh fire, or when you reload your existing fire. The use of a magnetic thermometer, a probe thermometer, or various digital readouts available on the market today will be of help in determining if the necessary temperature is achieved.
The heater may be equipped with a bypass mechanism, which permits the operator to "bypass" the smoke around the combustor when the necessary 350°-500° F. to start catalytic activity is not achieved, or when the operator is reloading the stove.
The proper use of the bypass mechanism and temperature gauge are the two most important things to learn when operating a catalytic combustor equipped device and if used properly will eliminate a large portion of combustor problems.
Another important thing to remember when operating a catalytic combustor equipped device (or any wood burning device) is to burn seasoned, dry wood only.
The gas discharge from a wood burning stove or heater, such as firebox 11, comprises carbon monoxide (CO), hydrocarbons (HC), i.e., smoke, and unburned or used oxygen. With a catalytic combustor containing a rare metal coating operating in a gas temperature atmosphere of 350°-500° F., the rare metal coating of the combustor agitates the molecules in the combustor for a further burning action of the discharge gases (smoke) of the heater.
The catalytic combustion action results in a burning action that creates a flue discharge of carbon dioxide and water containing a low creosote and air pollutant content. The exhaust gases are approximately 1400°-1700° F.
TEST PERFORMANCE
Tests were conducted on a 6" diameter heat reclaimer and catalytic combustor at Omni Environmental Services of Beaverton, Oreg. Results for a run of one heat output test showed marked improvement over a simple stove with a plain cylindrical chimney connector. Equivalent or higher performance than a multi-chambered stove with a catalytic combustor and plain cylindrical chimney connector occurred.
Specific data obtained:
Heat Output: 17,387 BTU/Hr.
Combustion Efficiency: 89.9%
Heat Transfer Efficiency: 85.4%
Overall Efficiency: 76.7%
CO: 0.43%
Particulates: 3.49 Grans/Hr.
Combustor 13, as shown in FIGS. 5 and 7, comprises, in addition to catalytic element 32, a rotatable cradle 33 and a housing 34.
Cradle 33 has the general form of a short cylindrical band with inwardly extending tabs 35 at its lower edge. Its inside diameter is just larger than the outside diameter of the disc-shaped catalytic element 32, so that when element 32 is dropped into cradle 33 from above the lower periphery of element 32, it rests upon tabs 35. A first support rod 36 extends radially from one side of cradle 33 and a second support rod 37 extends radially from the opposite side of cradle 33, 180° removed from first support rod 36. Rod 37 has a ninety degree bend at its outer end, the bend forming a handle 38 which is employed to rotate cradle 33 and with it element 32.
Housing 34 of combustor 13 comprises a short vertically mounted section of flue pipe 40 into which is cut a horizontal slot 39, the slot extending 180° about the pipe, and its height being somewhat greater than the height of cradle 33. A slot 41 is cut into each of the two lower corners of slot 39. A cover 42 having a shape and dimensions approximating but slightly greater than those of the section of pipe removed to form slot 39 is hinged at one vertical edge 43 of slot 39 and is secured in a closed position by a latch or hasp 44 at the opposite vertical edge of slot 39.
Combustor 13 is assembled by first placing element 32 inside cradle 33. Cradle 33 is then passed through slot 39 into housing 34, and is dropped into place with rods 36 and 37 supported within slots 41. Door 42 is then closed and secured by means of hasp 44. The outside diameter of cradle 33 is just sufficiently smaller than the inside diameter of housing 34 as to permit cradle 33 to be rotated about rods 36 and 37 within housing 34. Handle 38 is employed to rotate cradle 33 to the desired position which is horizontal when the combustor is to be operative and vertical when the catalytic element 32 is to be bypassed.
It will be noted that the constructions of housing 34 and cradle 33 readily accommodate the removal of cradle 33 and element 32 (for the cleaning or replacement of element 32) from the fully assembled appliance 10 without requiring the removal of a single pipe section of flue 16 or of any other associated hardware.
Augmenter 12 is a series of pipes and fittings which supply heated fresh air to the bottom side of the combustor through the top pipe which has a series of small holes.
Damper 15 is a conventional butterfly-type damper installed in flue 16 in the usual manner directly above heat exchanger 14, to obtain extended burning of fumes.
OPERATION
The operation of the subject invention occurs as follows:
Combustion occurring in heater 12 produces a natural convection flow beginning with the fresh air supply to the firebox and proceeding from firebox 11 upward through combustor 13 and heat exchanger 14 past damper 15, through flue 16 and out the chimney to the atmosphere.
The inlet air feeds the fire in firebox 11 supplying oxygen needed for combustion of the fuel which in the preferred embodiment may be firewood. Because the oxidation of the fuel is never complete, even under ideal conditions, combustion products in the firebox contain carbon monoxide, soot, creosote and other pollutants.
Because the oxygen content of the inlet air to firebox 11 has been severely depleted by the burning fuel, the oxygen content of the combustion products is undesirably low. This deficiency of oxygen is corrected by fresh hot air supplied by augmenter 12, the fresh supply of air mixing with the combustion products just prior to their entry into catalytic combustor 13.
Catalytic action within combustor 13, enhanced by the fresh air supply from augmenter 12 causes the pollutants to be oxidized, and the oxidation process releases additional heat, elevating the temperature of the exhaust gases which pass upward into heat exchanger 14.
The expanding circumference of expansion section 26 provides increased surface area for the radiation of heat into the living area, thereby increasing the amount of heat transferred.
To prevent separation of flow from the tapered wall of expansion section 26, the slope of the wall must be limited to less than 0.1228 with respect to the vertical axis of exchanger 14. Utilization of a greater slope, or rate of change of the circumference, for the wall of the expansion section will produce a separation of the flow from the wall of the expansion section with deleterious effects upon both the drafting function and the heat transfer rate.
Separation of the flow from the wall of the expansion section is further discouraged by the flow splitter plates 29 inside expansion section 26. The connected flow splitter plates, which are arranged radially about the axis of the expansion section, function with the wall of the expansion section to form separately diverging flow compartments. Each wall of each flow compartment may be arranged with a limiting slope of 0.1228 with respect to the centroidal axis of that flow compartment. For a frusto-conical-shaped expansion section enclosing a single tier of radially arranged flow splitter plates, the slope of the wall of the expansion section with respect to the axis of the heat exchanger 14 may be increased to a limiting value of 0.2493, thereby increasing further the overall area for heat transfer, while avoiding a disruption of the drafting function.
The idler section provides additional heat transfer area for the fully expanded flow. The reduction section 24 whose circumference gradually decreases in the direction of flow, converges the flow to enter the outlet section 18. The flow passes from the reduction section 24 through flue section 23 and into the exhaust pipe or chimney.
To render the catalytic converter element 32 inoperative, and to realize a maximum draft condition during the starting of a fire, the cradle 33 together with element 32 are rotated ninety degrees to a vertical position using handle 38.
FIGS. 9 through 15 disclose a further modification of the fuel burning appliance or stove 10 disclosed in FIGS. 1 through 8, wherein like parts of stove 45 are given the same reference characters as those used in FIGS. 1 through 8.
As noted from FIGS. 8, 9 and 10, stove 45 is provided with a smoke baffle 46 which is mounted horizontally substantially midway between the top 45' and bottom 45" of the firebox 11 of stove 45. The baffle rests on a plurality of right-angle clamps 47 secured to the inside walls of the firebox, as shown in FIGS. 11 and 14.
FIG. 9 illustrates that the modified air augmenter 48 differs from the structure 17, 18 and 19, shown in FIG. 1, by the addition of the perforated pipe 49 which distributes the added air more uniformly than the structure shown in FIG. 1. As noted, the air augmenter 48 is mounted between the top of smoke baffle 46 and the entranceway into flue 22.
In accordance with the invention claimed, a second catalytic combustor 13A is detachably mounted on the edge of smoke baffle 46. This combustor may be in the form of a rectangular box having a catalytic element 32 of the type shown in FIGS. 5 and 6, and described with regard thereto which, when clamped to the free edge 46' of baffle 46, will "burn" the smoke, carbon monoxide and particulates which are not burned by the fire in firebox 11.
As noted from FIG. 9, the smoke, carbon monoxide and particulates of the burning fire driven through the catalytic combustor 13A are burned in combustor 13A with any excess from the firebox by passing combustor 13A being driven into catalytic combustor 13. This excess by-product of the firebox together with the exhaust gases from catalytic combustor 13A are further burned in combustor 13.
Thus, a two-step process is disclosed together with structure for accomplishing the sequential burning in a pair of catalytic combustors, the by-products of the firebox of a stove. The action is a natural flow process requiring no manual controls.
The dual catalytic combustor function eliminates overloading of either of the combustors and substantially eliminates the possibility of exhausting into the atmosphere smoke, carbon monoxide and harmful particulates of the burned fuel gases.
Since the catalytic combustor 13A is provided with a plurality of clamp means 50 which slidably receive therebetween the edge 46' of baffle 46, the combustor may be readily removed from the stove 45 through its door 51 for cleaning and repair purposes.
As shown in FIGS. 8, 9, 10 and 13, an adjustable damper 52 is provided in the walls of the stove above door 51 which may open and close a passageway 53 formed therein for controlling atmospheric air into the firebox of the stove. This air passes downwardly over door 51 to the base of the firebox to keep the glass of the door clean and aids the fuel combustion and then passes through combustors 13A and 13 into flue 22.
This damper is controlled by rotation of its handle 54 to open and close its passageway 53 into the firebox.
An effective fuel burning appliance incorporating a catalytic combustor together with convenient means for the control and maintenance of the catalytic element is thus provided in accordance with the stated objects of the invention.
Although but a few embodiments of the invention have been shown and claimed, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. | A wood burning air augmented stove for reclaiming heat from the discharge gases employing a plurality of spaced catalytic combustors, one combustor being detachably mounted on the edge of a smoke baffle, and another combustor being positioned in a portion of the chimney flue which may be selectively moved from a gas intercepting position to a gas bypassing position. The catalytic combustors are so arranged that if one combustor is overheated, the second combustor will provide the additional gas heating and cleansing function needed. These combustors act in series to magnify temperature and heat increases. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent Application No. 61/652,933, filed on May 30, 2012, which is incorporated by reference herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with Government support under N00174-07-D-0008 awarded by NAVSEA Indian Head. The Government has certain rights in this invention.
BACKGROUND
[0003] Various unmanned submersible crafts are in use today by the military, scientific, and recreational communities. The submersible crafts may be used for a variety of tasks, and may be outfitted with a variety of equipment for performing those tasks.
[0004] One such task may include inspection of underwater structures or of the seafloor via sonar devices. However, due to size constrains, weight constraints, and cost, it may not be practical to outfit a submersible craft with a sonar system capable of directing sonar to both sides of the craft simultaneously. For example, the sonar might be limited to being directed out of the port side of the craft only. Thus, a need exists for a submersible craft that is capable of being inverted so as to direct the sonar out of the opposite side of the craft, and a system and method for achieving such an inversion.
SUMMARY
[0005] In one embodiment, a submersible craft is provided, the submersible craft comprising: an apparatus for selectively positioning a battery and a main electronics housing (“MEH”) within the submersible craft, the apparatus comprising: a battery; a battery rail apparatus comprising a first battery frame rail substantially vertically oriented within the submersible craft and a second battery frame rail substantially vertically oriented within the submersible craft, wherein the first battery frame rail is positioned on a first side of the submersible craft and the second battery frame rail is positioned on a second side of the submersible craft substantially opposite the first side of the submersible craft, wherein a first end of the battery is slidably connected to the first battery frame rail and a second end of the battery is slidably connected to the second battery frame rail; an MEH; an MEH rail apparatus comprising a first MEH frame rail substantially vertically oriented within the submersible craft and a second MEH frame rail substantially vertically oriented within the submersible craft, wherein the first MEH frame rail is positioned on a first side of the submersible craft and the second MEH frame rail is positioned on a second side of the submersible craft substantially opposite the first side of the submersible craft, wherein a first end of the MEH is slidably connected to the first MEH frame rail and a second end of the MEH is slidably connected to the second MEH frame rail; and wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy.
[0006] In another embodiment, a submersible craft is provided, the submersible craft comprising: an apparatus for selectively positioning a battery and an MEH within the submersible craft, the apparatus comprising: a battery rail apparatus comprising a first battery frame rail substantially vertically oriented within the submersible craft and a second battery frame rail substantially vertically oriented within the submersible craft, wherein the first battery frame rail is positioned on a first side of the submersible craft and the second battery frame rail is positioned on a second side of the submersible craft substantially opposite the first side of the submersible craft, and wherein the first battery frame rail and the second battery frame rail are configured to be slidably connected to first and second ends of a battery, respectively; an MEH rail apparatus comprising a first MEH frame rail substantially vertically oriented within the submersible craft and a second MEH frame rail substantially vertically oriented within the submersible craft, wherein the first MEH frame rail is positioned on a first side of the submersible craft and the second MEH frame rail is positioned on a second side of the submersible craft substantially opposite the first side of the submersible craft, and wherein the first MEH frame rail and the second MEH frame rail are configured to be slidably connected to first and second ends of an MEH.
[0007] In one embodiment, a system for selectively positioning a battery and an MEH within a submersible craft is provided, the system comprising: a battery; a battery rail apparatus comprising a first battery frame rail configured to be substantially vertically oriented within the submersible craft and a second battery frame rail configured to be substantially vertically oriented within the submersible craft, wherein the first battery frame rail is configured to be positioned on a first side of the submersible craft and the second battery frame rail is configured to be positioned on a second side of the submersible craft substantially opposite the first side of the submersible craft, wherein a first end of the battery is slidably connected to the first battery frame rail and a second end of the battery is slidably connected to the second battery frame rail; an MEH; an MEH rail apparatus comprising a first MEH frame rail configured to be substantially vertically oriented within the submersible craft and a second MEH frame rail configured to be substantially vertically oriented within the submersible craft, wherein the first MEH frame rail is configured to be positioned on a first side of the submersible craft and the second MEH frame rail is configured to be positioned on a second side of the submersible craft substantially opposite the first side of the submersible craft, wherein a first end of the MEH is slidably connected to the first MEH frame rail and a second end of the MEH is slidably connected to the second MEH frame rail; and wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy.
[0008] In another embodiment, an apparatus for selectively positioning a battery and an MEH within a submersible craft is provided, the apparatus comprising: a battery; a battery rail apparatus substantially vertically oriented within the submersible craft, wherein the battery rail apparatus includes a first battery rail and a second battery rail, and wherein the first battery rail and the second battery rail are slidably connected to the submersible craft; an MEH; an MEH rail apparatus substantially vertically oriented within the submersible craft, wherein the MEH rail apparatus includes a first MEH rail and a second MEH rail, and wherein the first MEH rail and the second MEH rail are slidably connected to the submersible craft; wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy.
[0009] In another embodiment, a method for selectively inverting a submersible craft is provided, the method comprising: providing a battery contained on a battery rail apparatus, wherein the battery rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the battery in one of a battery lower position and a battery upper position; providing an MEH contained on an MEH rail apparatus, wherein the MEH rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the MEH in one of an MEH upper position and an MEH lower position; providing an external shell upon the submersible craft; removing the external shell; moving the battery from the battery lower position to the battery upper position; moving the MEH from the MEH upper position to the MEH lower position, wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy; and replacing the external shell.
[0010] In another embodiment, a method for selectively inverting a submersible craft is provided, the method comprising: providing a battery contained on a battery rail apparatus, wherein the battery rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the battery in one of a battery lower position and a battery upper position; providing an MEH contained on an MEH rail apparatus, wherein the MEH rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the MEH in one of an MEH upper position and an MEH lower position; moving the battery from the battery lower position to the battery upper position; and moving the MEH from the MEH upper position to the MEH lower position, wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy.
[0011] In another embodiment, a method for selectively inverting a submersible craft is provided, the method comprising: moving a battery contained within the submersible craft from a battery lower position to a battery upper position; and moving an MEH within the submersible craft from an MEH upper position to an MEH lower position, wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying figures, which are incorporated in and constitute a part of the specification, illustrate various example apparatuses, systems, and methods, and are used merely to illustrate various example embodiments.
[0013] FIG. 1 illustrates an example arrangement of a submersible craft configured to selectively invert.
[0014] FIG. 2 illustrates an example arrangement of a submersible craft configured to selectively invert.
[0015] FIG. 3 illustrates an example arrangement of a submersible craft configured to selectively invert.
[0016] FIG. 4 illustrates an example arrangement of a battery in a submersible craft configured to selectively invert.
[0017] FIG. 5 is a flowchart illustrating an example method for inverting a submersible craft.
[0018] FIG. 6 is a flowchart illustrating an example method for inverting a submersible craft.
[0019] FIG. 7 is a flowchart illustrating an example method for inverting a submersible craft.
DETAILED DESCRIPTION
[0020] FIG. 1 illustrates a perspective view of an example arrangement of a submersible craft 100 configured to selectively invert. Submersible craft 100 may be configured to operate in a liquid medium, such as water. Submersible craft 100 includes a frame 102 , an MEH 104 , and a battery 106 . MEH 104 includes an MEH rail apparatus including a first MEH rail 108 and a second MEH rail 110 . Battery 106 includes a battery rail apparatus including a first battery rail 112 and a second battery rail 114 . In one embodiment, frame 102 further includes a first MEH frame rail 116 , a second MEH frame rail 118 , a first battery frame rail 120 , and a second battery frame rail 122 .
[0021] Submersible craft 100 may include any unmanned submersible craft. Submersible craft 100 may be fitted with various propulsion systems, including for example thrusters and propellers. Submersible craft 100 may be fitted with various steering components, including for example rudders and hydroplanes. In one embodiment, submersible craft 100 includes an exterior shell or fairing (not shown) which may be configured to provide protection to interior components and/or improve hydrodynamic characteristics of submersible craft 100 . The exterior shell or fairing may comprise at least one of a metal, polymer, and composite material. Submersible craft 100 may include various optical devices, including for example cameras. Submersible craft 100 may include a ballast device to affect its buoyancy.
[0022] Submersible craft 100 may additionally include a sonar device. In one embodiment, submersible craft 100 includes a sonar device configured to direct sonar out of only one side of the craft, including, for example, the port or starboard side of the craft. In one embodiment, submersible craft 100 is configured to invert by rotating 180 degrees about the x-axis and/or z-axis. As a result, the sonar device will selectively direct sonar out of either side of the craft.
[0023] Frame 102 may comprise the structural components of submersible craft 100 . In one embodiment, frame 102 includes a rigid tubing material. In another embodiment, frame 102 includes panels. In another embodiment, frame 102 includes a combination of rigid tubing material and panels. Frame 102 may comprise at least one of a metal, polymer, and composite material. In one embodiment, frame 102 comprises a tubing material oriented about the exterior of submersible craft 100 to provide both rigid structure to submersible craft 100 and protection of the various components of submersible craft 100 . In this embodiment, panels may be oriented on at least the port and starboard sides of submersible craft 100 and configured to support the various components of submersible craft 100 .
[0024] MEH 104 may include at least one of the electronic controls, signaling components, and processing components. In one embodiment, MEH 104 is the central computer of submersible craft 100 and is responsible for all electronic function of submersible craft 100 . In one embodiment, MEH 104 includes the electrical circuitry responsible for controls and signaling in submersible craft 100 . MEH 104 may be sealed so as to be at least substantially impervious to a liquid (e.g., water). In one embodiment, MEH 104 includes a series of wires and cables extending therefrom and connected to the various electrical components of submersible craft 100 . In another embodiment, MEH 104 is connected to a host vessel, which is one or more of physically, electrically, or optically connected to submersible craft 100 . In another embodiment, MEH 104 is connected to a host vessel, which is a ship on the surface of the water from which submersible craft 100 operates. In one embodiment, MEH 104 has a substantially positive buoyancy, wherein the weight of liquid that MEH 104 displaces is greater than the weight of MEH 104 . Stated alternatively, the buoyant force acting on MEH 104 is greater than the gravitational force acting on MEH 104 . In this embodiment, MEH 104 may have a tendency to float toward the surface of the liquid medium. In another embodiment, MEH 104 has a substantially negative buoyancy.
[0025] MEH 104 includes an MEH rail apparatus, including in one embodiment a first MEH rail 108 , a second MEH rail 110 , a first MEH frame rail 116 , and a second MEH frame rail 118 . In another embodiment, the MEH rail apparatus includes a first MEH rail 108 and a second MEH rail 110 . In another embodiment, MEH rail apparatus includes a first MEH frame rail 116 and a second MEH frame rail 118 . In one embodiment, the MEH rail apparatus is substantially vertically positioned within submersible craft 100 so as to be substantially parallel to the y-axis. First MEH rail 108 is positioned on a first side of submersible craft 100 , and second MEH rail 110 is positioned on a second side of submersible craft 100 . In one embodiment, first MEH rail 108 is positioned substantially opposite second MEH rail 110 . First MEH rail 108 and second MEH rail 110 may be removably connected to a first and second end of MEH 104 , respectively, for example, through the use of bolts, screws, rivets, pins, straps, cam locks, and keyhole slots. In another embodiment, first MEH rail 108 and second MEH rail 110 are integrally connected to a first and second end of MEH 104 , respectively. First MEH rail 108 and second MEH rail 110 may comprise at least one of a metal, a polymer, and a composite material.
[0026] First MEH frame rail 116 and second MEH frame rail 118 may be removably connected to submersible craft 100 and/or frame 102 , for example, through the use of bolts, screws, rivets, pins, straps, cam locks, and keyhole slots. In another embodiment, first MEH frame rail 116 and second MEH frame rail 118 are integrally connected to frame 102 . First MEH frame rail 116 and second MEH frame rail 118 may comprise at least one of a metal, a polymer, and a composite material. In one embodiment, first MEH frame rail 116 and second MEH frame rail 118 are substantially vertically positioned within submersible craft 100 so as to be substantially aligned with the y-axis.
[0027] In one embodiment, first MEH rail 108 and second MEH rail 110 are slidably connected to first MEH frame rail 116 and second MEH frame rail 118 , respectively. In one embodiment, first MEH rail 108 and second MEH rail 110 include at least one of a groove, a ridge, and a channel configured to mate in slidable connection with a corresponding groove, ridge, or channel on first MEH frame rail 116 and second MEH frame rail 118 . In another embodiment, first MEH rail 108 and second MEH rail 110 include a ring or rod configured to mate in slidable connection with a corresponding ring or rod on first MEH frame rail 116 and second MEH frame rail 118 , such that the ring portion fits around the periphery of the rod portion and is able to selectively slide along the rod. In one embodiment, first MEH rail 108 slidably connects to first MEH frame rail 116 , and second MEH rail 110 slidably connects to second MEH frame rail 118 . In one embodiment, a first end of MEH 104 is slidably connected to first MEH frame rail 116 and a second end of MEH 104 is slidably connected to second MEH frame rail 118 .
[0028] In one embodiment, one or more of first MEH rail 108 , second MEH rail 110 , first MEH frame rail 116 , and second MEH frame rail 118 may include devices to assist in the slidable connection, including for example bearing surfaces or roller bearings.
[0029] In one embodiment, first MEH rail 108 and second MEH rail 110 are selectively slidably connected to first MEH frame rail 116 and second MEH frame rail 118 , respectively, and at least one of first MEH rail 108 , second MEH rail 110 , first MEH frame rail 116 , and second MEH frame rail 118 include at least one stop configured to act as the bound of slidable movement of MEH 104 . In one embodiment, the at least one stop is removably connected to at least one of first MEH rail 108 , second MEH rail 110 , first MEH frame rail 116 , and second MEH frame rail 118 , for example, through the use of bolts, screws, rivets, pins, straps, cam locks, and keyhole slots. In another embodiment, the at least one stop is integrally connected to at least one of first MEH rail 108 , second MEH rail 110 , first MEH frame rail 116 , and second MEH frame rail 118 . In one embodiment, each set of corresponding rails (i.e., first MEH rail 108 and first MEH frame rail 116 , and second MEH rail 110 and second MEH frame rail 118 ) includes an upper stop and lower stop (as defined by the y-axis), such that the slidable movement of MEH 104 is constrained between the upper stop and the lower stop.
[0030] In one embodiment, MEH 104 is selectively slidably positioned in relation to submersible craft 100 . MEH 104 may be selectively locked in an MEH upper position and MEH lower position. In one embodiment, MEH 104 is selectively locked into position by one or more of a captive screw, a bolt, a pin, a clip, and a strap. In one embodiment, MEH 104 is selectively locked into position using a captive screw configured to engage at least one of first MEH rail 108 , second MEH rail 110 , first MEH frame rail 116 , and second MEH frame rail 118 and prevent movement between first MEH rail 108 and first MEH frame rail 116 , and between second MEH rail 110 and second MEH frame rail 118 . In another embodiment, MEH 104 is selectively locked into position using a captive screw configured to engage MEH 104 with frame 102 . In another embodiment, MEH 104 is selectively locked into position using a captive screw configured to engage at least one of first MEH rail 108 , second MEH rail 110 , first MEH frame rail 116 , and second MEH frame rail 118 with frame 102 .
[0031] Battery 106 may include any known battery device capable of storing electrical energy. In one embodiment, battery 106 is configured to electrically connect to MEH 104 thereby providing electrical energy to MEH 104 . In another embodiment, battery 106 is electrically connected to the various electrical components within submersible craft 100 thereby providing electrical energy to the various electrical components within submersible craft 100 . In one embodiment, battery 106 sealed so as to be at least substantially impervious to a liquid (e.g., water). In one embodiment, battery 106 has a substantially negative buoyancy, wherein the weight of liquid that battery 106 displaces is less than the weight of battery 106 . Stated alternatively, the buoyant force acting on battery 106 is less than the gravitational force acting on battery 106 . In this embodiment, battery 106 may have a tendency to sink toward the floor of the liquid medium. In another embodiment, battery 106 has a substantially positive buoyancy. In one embodiment, battery 106 may include a mass that is greater than the mass of MEH 104 . In another embodiment, battery 106 may include a mass that is less than the mass of MEH 104 .
[0032] Battery 106 includes a battery rail apparatus, including first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 . In another embodiment, battery rail apparatus includes a first battery rail 112 and a second battery rail 114 . In another embodiment, the battery rail apparatus includes a first battery frame rail 120 and a second battery frame rail 122 . In one embodiment, the battery rail apparatus is substantially vertically positioned within submersible craft 100 so as to be substantially aligned with the y-axis. First battery rail 112 is positioned on a first side of submersible craft 100 , and second battery rail 114 is positioned on a second side of submersible craft 100 . In one embodiment, first battery rail 112 is positioned opposite second battery rail 114 . First battery rail 112 and second battery rail 114 may be removably connected to a first and second end of battery 106 , respectively, for example, through the use of bolts, screws, rivets, pins, straps, cam locks, and keyhole slots. In another embodiment, first battery rail 112 and second battery rail 114 are integrally connected to a first and second end of battery 106 , respectively. First battery rail 112 and second battery rail 114 may comprise at least one of a metal, a polymer, and a composite material.
[0033] First battery frame rail 120 and second battery frame rail 122 may be removably connected to frame 102 , for example, through the use of bolts, screws, rivets, pins, straps, cam locks, and keyhole slots. In one embodiment, first battery frame rail 120 and second battery frame rail 122 are integrally connected to frame 102 . First battery frame rail 120 and second battery frame rail 122 may comprise at least one of a metal, a polymer, and a composite material. In one embodiment, first battery frame rail 120 and second battery frame rail 122 are substantially vertically positioned within submersible craft 100 so as to be substantially aligned with the y-axis.
[0034] In one embodiment, first battery rail 112 and second battery rail 114 are slidably connected to first battery frame rail 120 and second battery frame rail 122 , respectively. In one embodiment, first battery rail 112 and second battery rail 114 include at least one of a groove, a ridge, and a channel configured to mate in slidable connection with a corresponding groove, ridge, or channel on first battery frame rail 120 and second battery frame rail 122 . In another embodiment, first battery rail 112 and second battery rail 114 include a ring or rod configured to mate in slidable connection with a corresponding ring or rod on first battery frame rail 120 and second battery frame rail 122 , such that the ring portion fits around the periphery of the rod portion and is able to selectively slide along the rod. In one embodiment, first battery rail 112 slidably connects to first battery frame rail 120 , and second battery rail 114 slidably connects to second battery frame rail 122 . In one embodiment, a first end of battery 106 is slidably connected to first battery frame rail 120 and a second end of battery 106 is slidably connected to second battery frame rail 122 .
[0035] In one embodiment, one or more of first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 may include devices to assist in the slidable connection, including for example bearing surfaces or roller bearings.
[0036] In one embodiment, first battery rail 112 and second battery rail 114 are selectively slidably connected to first battery frame rail 120 and second battery frame rail 122 , respectively, and at least one of first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 include at least one stop configured to act as the bound of slidable movement of battery 106 . In one embodiment, the at least one stop is removably connected to at least one of first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 , for example, through the use of bolts, screws, rivets, pins, straps, cam locks, and keyhole slots. In another embodiment, the at least one stop is integrally connected to at least one of first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 . In one embodiment, each set of corresponding rails (i.e., first battery rail 112 and first battery frame rail 120 , and second battery rail 114 and second battery frame rail 122 ) includes an upper stop and lower stop (as defined by the y-axis), such that the slidable movement of battery 106 is constrained between the upper stop and the lower stop.
[0037] In one embodiment, battery 106 is selectively slidably positioned in relation to submersible craft 100 . Battery 106 may be selectively locked in a battery upper position and a battery lower position. In one embodiment, battery 106 is selectively locked into position by one or more of a captive screw, a bolt, a pin, a clip, and a strap. In one embodiment, battery 106 is selectively locked into position using a captive screw configured to engage at least one of first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 , and prevent movement between first battery rail 112 and first battery frame rail 120 , and between second battery rail 114 and second battery frame rail 122 . In another embodiment, battery 106 is selectively locked into position using a captive screw configured to engage battery 106 with frame 102 . In another embodiment, battery 106 is selectively locked into position using a captive screw configured to engage at least one of first battery rail 112 , second battery rail 114 , first battery frame rail 120 , and second battery frame rail 122 with frame 102 .
[0038] In one embodiment, submersible craft 100 includes: an apparatus for selectively positioning battery 106 and MEH 104 within the submersible craft 100 , the apparatus comprising: battery 106 ; a battery rail apparatus comprising first battery frame rail 120 substantially vertically oriented within submersible craft 100 and second battery frame rail 122 substantially vertically oriented within submersible craft 100 , wherein first battery frame rail 120 is positioned on a first side of submersible craft 100 and second battery frame rail 122 is positioned on a second side of submersible craft 100 substantially opposite the first side of submersible craft 100 . The apparatus additionally comprises a first end of battery 106 slidably connected to first battery frame rail 120 and a second end of battery 106 slidably connected to second battery frame rail 122 . The apparatus further includes MEH 104 ; an MEH rail apparatus comprising first MEH frame rail 116 substantially vertically oriented within submersible craft 100 and second MEH frame rail 118 substantially vertically oriented within submersible craft 100 , wherein first MEH frame rail 116 is positioned on a first side of submersible craft 100 and second MEH frame rail 118 is positioned on a second side of submersible craft 100 substantially opposite the first side of submersible craft 100 . A first end of MEH 104 is slidably connected to first MEH frame rail 116 and a second end of MEH 104 is slidably connected to second MEH frame rail 118 . In one embodiment, battery 106 comprises a substantially negative buoyancy and MEH 104 comprises a substantially positive buoyancy.
[0039] In another embodiment, a submersible craft 100 comprises: an apparatus for selectively positioning battery 106 and MEH 104 within submersible craft 100 , the apparatus comprising: a battery rail apparatus comprising first battery frame rail 120 substantially vertically oriented within submersible craft 100 and second battery frame rail 122 substantially vertically oriented within submersible craft 100 , wherein first battery frame rail 120 is positioned on a first side of submersible craft 100 and second battery frame rail 122 is positioned on a second side of submersible craft 100 substantially opposite the first side of submersible craft 100 . First battery frame rail 120 and second battery frame rail 122 are configured to be slidably connected to first and second ends of battery 106 , respectively. The apparatus also comprises an MEH rail apparatus comprising first MEH frame rail 116 substantially vertically oriented within submersible craft 100 and second MEH frame rail 118 substantially vertically oriented within submersible craft 100 , wherein first MEH frame rail 116 is positioned on a first side of submersible craft 100 and second MEH frame rail 118 is positioned on a second side of submersible craft 100 substantially opposite the first side of submersible craft 100 . First MEH frame rail 116 and second MEH frame rail 118 are configured to be slidably connected to first and second ends of MEH 104 .
[0040] In one embodiment, a system for selectively positioning battery 106 and MEH 104 within submersible craft 100 is provided, the system comprising: battery 106 ; a battery rail apparatus comprising first battery frame rail 120 configured to be substantially vertically oriented within submersible craft 100 and second battery frame rail 122 configured to be substantially vertically oriented within submersible craft 100 , wherein first battery frame rail 120 is configured to be positioned on a first side of submersible craft 100 and second battery frame rail 122 is configured to be positioned on a second side of submersible craft 100 substantially opposite the first side of submersible craft 100 . A first end of battery 106 is slidably connected to first battery frame rail 120 and a second end of the battery is slidably connected to second battery frame rail 122 . The apparatus also includes MEH 104 ; an MEH rail apparatus comprising first MEH frame rail 116 configured to be substantially vertically oriented within submersible craft 100 and second MEH frame rail 118 configured to be substantially vertically oriented within submersible craft 100 , wherein first MEH frame rail 116 is configured to be positioned on a first side of submersible craft 100 and second MEH frame rail 118 is configured to be positioned on a second side of submersible craft 100 substantially opposite the first side of submersible craft 100 . A first end of MEH 104 is slidably connected to first MEH frame rail 116 and a second end of MEH 104 is slidably connected to second MEH frame rail 118 . Battery 106 comprises a substantially negative buoyancy and MEH 104 comprises a substantially positive buoyancy.
[0041] In another embodiment, an apparatus for selectively positioning battery 106 and MEH 104 within submersible craft 100 is provided, the apparatus comprising: battery 106 ; a battery rail apparatus substantially vertically oriented within submersible craft 100 , wherein the battery rail apparatus includes first battery rail 112 and second battery rail 114 , and wherein first battery rail 112 and second battery rail 114 are slidably connected to submersible craft 100 . The apparatus also includes MEH 104 ; an MEH rail apparatus substantially vertically oriented within submersible craft 100 , wherein the MEH rail apparatus includes first MEH rail 108 and second MEH rail 110 , and wherein first MEH rail 108 and second MEH rail 110 are slidably connected to submersible craft 100 . Battery 106 comprises a substantially negative buoyancy and MEH 104 comprises a substantially positive buoyancy.
[0042] FIG. 2 illustrates a top plan view of an example arrangement of a submersible craft 200 configured to selectively invert. Submersible craft 200 includes a frame 202 , an MEH 204 , and a battery 206 . MEH 204 includes an MEH rail apparatus including a first MEH rail 208 and a second MEH rail 210 . Battery 206 includes a battery rail apparatus including a first battery rail 212 and a second battery rail 214 . In one embodiment, frame 202 further includes a first MEH frame rail 216 , a second MEH frame rail 218 , a first battery frame rail 220 , and a second battery frame rail 222 .
[0043] FIG. 3 illustrates a perspective view of an example arrangement of a submersible craft 300 configured to selectively invert. Submersible craft 300 includes a frame 302 . In one embodiment, frame 302 further includes a first MEH frame rail 316 , a second MEH frame rail 318 , a first battery frame rail 320 , and a second battery frame rail 322 .
[0044] FIG. 4 illustrates a perspective view of an example arrangement of battery 406 in a submersible craft configured to selectively invert (not shown). Battery 406 includes a battery rail apparatus including a first battery rail 412 and a second battery rail 414 . In one embodiment, battery 406 includes a first battery rail attachment 424 and a second battery rail attachment 426 . First battery rail attachment 424 and second battery rail attachment 426 may be configured to attach battery 406 to first battery rail 412 and second battery rail 414 , respectively. In another embodiment, first battery rail attachment 424 and second battery rail attachment 426 may be removably or integrally connected to a battery cradle (not shown), which is configured to contain and support battery 406 . The battery cradle may comprise at least one of a metal, a polymer, or a composite material. In one embodiment, a battery cradle is removably or integrally connected to at least one of first battery rail 412 and a second battery rail 414 . In another embodiment, a battery cradle is slidably connectable to at least one of a first battery frame rail (not shown) and a second battery frame rail (not shown).
[0045] In operation, submersible craft 100 , 200 , and 300 may include a sonar device configured to direct sonar out of a single side of the craft (e.g., port side only). When it is desired to direct sonar out of the opposite side of submersible craft 100 , 200 , and 300 (e.g., from port side to starboard side), submersible craft 100 , 200 , and 300 may be inverted 180 degrees about the x-axis and/or z-axis, thereby causing sonar to be directed out of the opposite side of submersible craft 100 , 200 , and 300 (e.g., the starboard side). In one embodiment, submersible craft 100 , 200 , and 300 is symmetrical about its horizontal plane (x-z plane), such that the craft's upper portion is a mirror image of its lower portion. In such an embodiment, the symmetry of submersible craft 100 , 200 , and 300 permits operation of submersible craft 100 , 200 , and 300 in an inverted state that is essentially identical to its operation in a normal state. In one embodiment, submersible craft 100 , 200 , and 300 is permeable to the liquid medium. In another embodiment, submersible craft 100 , 200 , and 300 is configured to operate while flooded with liquid medium.
[0046] Although not wishing to be bound by a particular theory, submersible craft 100 , 200 , and 300 has a center of buoyancy and a center of gravity when submerged. A submerged craft's center of buoyancy is its immersed center of mass. Stated differently, submerged craft's center of buoyancy is the point through which the resultant force is exerted on a body by a static fluid in which it is submerged, and which is located at the centroid of displaced volume.
[0047] In an embodiment where at least a portion of a submersible craft is permeable to a liquid and/or configured to operate while flooded, the various components within the submersible craft may have various centers of buoyancy. In this embodiment, the center of buoyancy of the submersible craft as a whole is the central point of the individual centers of buoyancy of the various components. The location of the center of buoyancy of the submersible craft may be calculated using vector addition and accounting for the position of the various individual centers of buoyancy, as well as the value of the buoyant force at each of the various individual centers of buoyancy. In this sense, the position of components within the submersible vehicle that have positive buoyancy have an effect on the center of buoyancy of the submersible vehicle.
[0048] A submerged craft's center of gravity is the point from which the weight of the submerged craft may be considered to act. Stated alternatively, a submerged craft's center of gravity is the point in or near the craft at which the gravitational potential energy of the craft is equal to that of a single particle of the same mass located at that point and through which the resultant of the gravitational forces on the component particles of the craft acts. In this sense, the position of components within the submersible vehicle has an effect on the center of gravity of the submersible vehicle.
[0049] The center of buoyancy of submersible craft 100 , 200 , and 300 creates a force upward from submersible craft 100 , 200 , and 300 toward the surface of the liquid medium in which it operates. The center of gravity of submersible craft 100 , 200 , and 300 creates a force downward from submersible craft 100 , 200 , and 300 toward the floor of the liquid medium in which it operates. If there is a differential between the center of buoyancy of submersible craft 100 , 200 , and 300 and the center of gravity of submersible craft 100 , 200 , and 300 , such as through a difference in position of the battery 106 , 206 , and 406 and MEH 104 and 204 , then submersible craft 100 , 200 , and 300 will orient itself such that its center of gravity is below its center of buoyancy. Accordingly, if battery 106 , 206 , and 406 comprises a substantially negative buoyancy and MEH 104 and 204 comprises a substantially positive buoyancy, then shifting battery 106 , 206 , and 406 to an upper position within submersible craft 100 , 200 , and 300 using a battery rail apparatus and shifting MEH 104 and 204 to a lower position within submersible craft 100 , 200 , and 300 using an MEH rail apparatus will cause the center of gravity of submersible craft 100 , 200 , and 300 to be higher than its center of buoyancy upon replacement in a liquid medium. The result of such a relationship between the center of gravity of submersible craft 100 , 200 , and 300 and the center of buoyancy of submersible craft 100 , 200 , and 300 is that submersible craft 100 , 200 , and 300 will invert when placed back in the liquid medium, so as to orient its center of gravity lower than its center of buoyancy, and its substantially negative buoyancy battery 106 , 206 , and 406 lower than its substantially positive buoyancy MEH 104 and 204 .
[0050] In another embodiment, MEH 104 and 204 can comprise a substantially negative buoyancy and battery 106 , 206 , and 406 can comprise a substantially positive buoyancy. Accordingly, if battery 106 , 206 , and 406 comprises a substantially positive buoyancy and MEH 104 and 204 comprises a substantially negative buoyancy, then shifting battery 106 , 206 , and 406 to a lower position within submersible craft 100 , 200 , and 300 , and shifting MEH 104 and 204 to an upper position within submersible craft 100 , 200 , and 300 will cause the center of gravity of submersible craft 100 , 200 , and 300 to be higher than its center of buoyancy. The result of such a relationship between the center of gravity of submersible craft 100 , 200 , and 300 and the center of buoyancy of submersible craft 100 , 200 , and 300 is that submersible craft 100 , 200 , and 300 will invert when placed back in the liquid medium, so as to orient its center of gravity lower than its center of buoyancy.
[0051] FIG. 5 is a flowchart illustrating an example method for selectively inverting a submersible craft within a liquid medium. As shown in FIG. 5 , the example method includes providing a battery contained on a battery rail apparatus, wherein the battery rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the battery in one of a battery lower position and a battery upper position (step 500 ). An MEH is provided contained on an MEH rail apparatus, wherein the MEH rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the MEH in one of an MEH upper position and an MEH lower position (step 510 ). An external shell is provided upon the submersible craft (step 520 ). The example method further includes removing the submersible craft from the liquid medium (step 530 ) and removing the external shell (step 540 ). The battery is moved from the battery lower position to the battery upper position (step 550 ) while the MEH is moved from the MEH upper position to the MEH lower position wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy (step 560 ). Finally, the method includes replacing the external shell (step 570 ), replacing the submersible craft into the liquid medium (step 580 ), and allowing the submersible craft to invert within the liquid medium (step 590 ).
[0052] In steps 540 and 570 , the external shell may be removably fixed to frame 102 , 202 , and 302 using external shell fasteners, including for example captive screws, screws, bolts, clips, pins, straps, or cam locks. Removal and replacement of the external shell may include simply removing and replacing the external shell fasteners.
[0053] In step 550 , moving battery 106 , 206 , and 406 from a battery lower position to a battery upper position may include removing for example a captive screw, bolt, pin, clip, or strap locking battery in battery lower position, sliding battery along battery rail apparatus to battery upper position until it encounters an upper stop, and replacing a captive screw, bolt, pin, clip, or strap locking battery in battery upper position.
[0054] In step 560 , moving MEH 104 and 204 from an MEH upper position to an MEH lower position may include removing for example a captive screw, bolt, pin, clip, or strap locking MEH in MEH upper position, sliding MEH along MEH rail apparatus to MEH lower position until it encounters a lower stop, and replacing a captive screw, bolt, pin, clip, or strap locking MEH in MEH lower position.
[0055] In steps 530 and 580 , the removal and replacement of submersible craft 100 , 200 , and 300 from the liquid medium may involve temporarily placing submersible craft 100 , 200 , and 300 on the deck of a ship, on land, on a dock, or on a stationary platform above the surface of the liquid medium. In one embodiment, the liquid medium is water in a pond, lake, stream, river, or ocean.
[0056] In step 590 , submersible craft 100 , 200 , and 300 will attempt to invert without external force because it will orient its center of gravity below its center of buoyancy. However, in one embodiment it may be necessary to physically assist submersible craft 100 , 200 , and 300 in initially inverting.
[0057] In one embodiment, submersible craft 100 , 200 , and 300 further includes an acoustic beacon and/or relocation transponder. In one embodiment, the acoustic beacon/relocation transponder must be directed toward the surface of the liquid medium. In such an embodiment, the method of inverting submersible craft 100 , 200 , and 300 further includes adjusting the orientation of acoustic beacon/relocation transponder so it points downward during the flipping procedure. Upon replacement of submersible craft 100 , 200 , and 300 in the liquid medium, submersible craft 100 , 200 , and 300 will invert to orient its center of gravity below its center of buoyancy, thus causing acoustic beacon/relocation transponder to be directed upwardly toward the surface of the liquid medium after inversion of submersible craft 100 , 200 , and 300 .
[0058] In one embodiment, submersible craft 100 , 200 , and 300 further includes a tether strain relief physically attaching submersible craft 100 , 200 , and 300 to a host ship, dry land, a dock, or a platform above the liquid medium. Tether strain relief may be physically attached to a lower portion of frame 102 , 202 , and 302 . In such an embodiment, the method of inverting submersible craft 100 , 200 , and 300 further includes removing tether strain relief from submersible craft 100 , 200 , and 300 and reattaching it toward the top of submersible craft 100 , 200 , and 300 during the flipping procedure. Upon replacement of submersible craft 100 , 200 , and 300 in the liquid medium, submersible craft 100 , 200 , and 300 will invert to orient its center of gravity below its center of buoyancy, thus causing tether strain relief to be attached toward the bottom of submersible craft 100 , 200 , and 300 after inversion of submersible craft 100 , 200 , and 300 .
[0059] FIG. 6 is a flowchart illustrating an example method for selectively inverting a submersible craft within a liquid medium. As shown in FIG. 6 the example method includes providing a battery contained on a battery rail apparatus, wherein the battery rail apparatus is substantially vertically positioned within the submersible craft and is configured to selectively position the battery in one of a battery lower position and a battery upper position (step 600 ). An MEH is provided contained on an MEH rail apparatus, which is substantially vertically positioned within the submersible craft and is configured to selectively position the MEH in one of an MEH upper position and an MEH lower position (step 610 ). The example method further includes moving the battery from the battery lower position to the battery upper position (step 620 ) and moving the MEH from the MEH upper position to the MEH lower position wherein the battery comprises a substantially negative buoyancy and the MEH comprises a substantially positive buoyancy (step 630 ). Finally, the example method includes allowing the submersible craft to invert within the liquid medium (step 640 ).
[0060] FIG. 7 is a flowchart illustrating an example method for selectively inverting a submersible craft within a liquid medium. As shown in FIG. 7 the example method includes moving a battery contained within the submersible craft from a battery lower position to a battery upper position (step 700 ) and moving an MEH within the submersible craft from an MEH upper position to an MEH lower position (step 710 ). Finally, the example method includes allowing the submersible craft to invert within the liquid medium (step 720 ).
[0061] To the extent that the term “includes” or “including” is used in the specification or the claims, it is intended to be inclusive in a manner similar to the term “comprising” as that term is interpreted when employed as a transitional word in a claim. Furthermore, to the extent that the term “or” is employed (e.g., A or B) it is intended to mean “A or B or both.” When the applicants intend to indicate “only A or B but not both” then the term “only A or B but not both” will be employed. Thus, use of the term “or” herein is the inclusive, and not the exclusive use. See Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). Also, to the extent that the terms “in” or “into” are used in the specification or the claims, it is intended to additionally mean “on” or “onto.” To the extent that the term “selectively” is used in the specification or the claims, it is intended to refer to a condition of a component wherein a user of the apparatus may activate or deactivate the feature or function of the component as is necessary or desired in use of the apparatus. To the extent that the term “operatively connected” is used in the specification or the claims, it is intended to mean that the identified components are connected in a way to perform a designated function. As used in the specification and the claims, the singular forms “a,” “an,” and “the” include the plural. Finally, where the term “about” is used in conjunction with a number, it is intended to include ±10% of the number. In other words, “about 10” may mean from 9 to 11.
[0062] As stated above, while the present application has been illustrated by the description of embodiments thereof, and while the 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, having the benefit of the present application. Therefore, the application, in its broader aspects, is not limited to the specific details, illustrative examples shown, or any apparatus referred to. Departures may be made from such details, examples, and apparatuses without departing from the spirit or scope of the general inventive concept. | Autonomous, unmanned submersible can turn upside down in order to use instrumentation placed on one side only. Batteries ( 106 ) and instrumentation housing ( 104 ) are installed on frame rails ( 112,14,108,110 ) and can change their relative positions, thus inverting the relative positions between center of buoyancy and center of gravity and subsequently inverting the submersible. | 8 |
BACKGROUND
[0001] Many service providers, such as wireless telecommunications carriers, VoIP (Voice over Internet Protocol) carriers, long distance carriers, LECs (local exchange carriers), cable television providers, satellite television and/or radio providers, etc., all share common needs to analyze network capacity and plan for network evolution based, in part, on user or subscriber usage and growth. For instance, wireless telecommunications carriers and satellite telecommunications carriers are experiencing substantial user growth, and therefore need to implement reliable and efficient analytical methodologies to anticipate and plan for network evolution. Because networks are composed of multiple nodes with various functionalities, all of which impact user experience, service providers need to analyze such network nodes to ensure that each node has capacity to meet evolving user use and growth. Thus, there exists a need for a robust, reliable, efficient analytical method and system to analyze node capacities in order to inform network planning and evolution.
SUMMARY OF THE INVENTION
[0002] Embodiments of the present invention involve a user based dimensioning analysis involving calculation of network node capacity in terms of a “supportable users” metric. For example, a method measures current utilization levels for one or a plurality of network nodes against then-current number of users utilizing a service involving the node(s), and calculating a maximum number of supportable users of such node(s). The method forecasts or predicts at least one future supportable users level that can be sustained by the network. The method expands the network resource based at least in part on the ratio of the future user forecast and the current maximum supportable user capacity.
[0003] In an embodiment, a method of supportable user based dimensioning involves measuring a current user level and measuring respective current utilization levels for a plurality of constraints. The plurality of constraints represent a network resource service. In a further embodiment, the method involves determining respective maximum utilization levels for the plurality of constraints. A calculation of a current maximum supportable users capacity is conducted based at least in part on the current user level, the current utilization levels of the plurality of constraints, and/or the maximum utilization levels of the plurality of constraints.
[0004] In an embodiment, the current utilization levels include memory utilization, signaling links capacity utilization, processor utilization, transactions per second and/or any other constraint.
[0005] In an embodiment, the signaling link utilization may employ the SS7 (Signaling System #7), SIGTRAN (Signaling Transport), SCTP (Stream Control Transmission Protocol), IP (Internet Protocol), or other protocols.
[0006] In an embodiment, the user is a wireless communication customer, and the network resource service is a wireless communication service provider.
[0007] In an embodiment, expanding the network resource includes adding sets of hardware, where each set has a user capacity, or a number of supportable users, associated with it representing an amount of maximum supportable users that are expected to increase after the set has been added to the network resource, and where the set configuration and associated number of supportable users is predetermined.
[0008] In an embodiment of the present invention, a system and method of user based dimensioning is provided. An embodiment includes a plurality of components organized in a network of nodes, where the plurality is configured to provide a network resource service. An embodiment includes a current supportable users level, and each component of the embodiment may include a current utilization level. An embodiment allows for a current maximum user capacity based at least in part on the current supportable users level and the current utilization levels of the plurality of components. An embodiment is configured to expand based at least in part on a ratio of a future user forecast and the current maximum user capacity. These embodiments can be used in various combinations with and/or without each other.
[0009] In an embodiment, current utilization levels include, but are not necessary limited to, memory utilization, signaling links capacity utilization, and/or processor utilization.
[0010] In an embodiment, signaling link utilization may involve the SS7, SIGTRAN, SCTP, IP, or other protocols.
[0011] In an embodiment, the user is a wireless communication customer, and the network resource service is one or more wireless communication service providers.
[0012] In an embodiment, the expandable network resource may include being configured to add sets of hardware, where each set has supportable users associated with it representing an amount the maximum supportable users are expected to increase after the set has been added to the network resource, and where the set configuration and associated number of users is predetermined.
[0013] An example system of user based dimensioning includes a network resource service or the like. The network resource service having a plurality of constraints and/or components. In the system, a measurement of a current user level is taken. And, a measurement of a respective current utilization level for each constraint and/or component of the plurality of constraints is taken. In the system, a determination of a respective maximum utilization level for each constraint and/or component of the plurality of constraints is made. In the system, a current maximum supportable users capacity is based on the current user level, the respective current utilization levels of each constraint and/or component of the plurality of constraints and/or component, and the respective maximum utilization levels of each constraint and/or component of the plurality of constraints and/or components.
[0014] An example embodiment of the present invention provides a computer-readable storage medium encoded with instructions configured to be executed by a processor, the instructions which, when executed by the processor, cause the performance of one or more of the example methods described herein. An example method calculates a current user level. An example method measures the current utilization levels for a plurality of components and/or constraints, where the plurality of components and/or constraints represent a network resource service. An example method calculates current maximum supportable users, based at least in part on the current user level, the current utilization levels of the plurality of components and/or constraints, and/or maximum capacity of the components. An example method forecasts and/or predicts at least one future supportable users level, An example method expands the network resource based at least in part on the ratio of the future user forecast and the current maximum supportable users capacity for multiple constraints and/or components. These methods described may be used in combination with and/or without each other.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 illustrates an example method according to an example embodiment of the present invention.
[0016] FIG. 2 illustrates another example method according to an example embodiment of the present invention.
[0017] FIG. 3 illustrates an example node system according to an example embodiment of the present invention.
[0018] FIG. 4 illustrates an example network system according to an example embodiment of the present invention.
DETAILED DESCRIPTION
[0019] Services companies (e.g., a cellular communications company, a VoIP carrier, a long distance carrier, an LEC, a cable television provider, a satellite television provider, a satellite radio provider) generally are composed of two broad groups with considerable operational overlap and/or interaction. For example, one group may deal primarily with non-technical business issues, such as sales, accounting, marketing, management, business development, and other nontechnical functions. The other group may deal with technical issues and be responsible for planning, purchasing, installing, maintaining, engineering, administering, and upgrading the technical infrastructure required to provide the services being provided by the company to its customers. There are, of course, some groups with overlap between these two general areas. For example, a product development group or an engineering group may include technical people tasked to address technical issues pertaining to the company's network operations, as well as nontechnical people tasked to address, for instance, financial planning involving the network. Unfortunately, each group will approach common or shared issues with analytical tools unique to their disciplines, thereby creating inefficiencies based on incompatible analytical methodologies. For reasons of simplicity, monetary and analytical efficiency, and clarity across such groups and the corporate structure as a whole, a company may find it beneficial to implement a unified analytical method incorporating a single metric for use in analyzing network planning. Example embodiments of the present invention include systems and methods for unifying the great variety of technical metrics under one metric that can be easily understood by various groups across the company.
[0020] The following description provides specific details for a thorough understanding of, and enabling description for, various embodiments of the method and system. One skilled in the art will understand that the method(s) and system(s) may be practiced without many of these details. In some instances, well-known structures and functions have not been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments of the method and system. It is intended that the terminology used in the description presented below be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain embodiments of the technology. Although certain terms may be emphasized below, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section.
[0021] Some of the example embodiments use a cellular telecommunications company to illustrate some benefits and details of the present invention. It will be appreciated that the present invention may be practiced in connection with any network operation, and is not limited to cellular telecommunications networks. A single user metric is believed to be a useful, and to-be, universally acceptable analytical metric because most, if not all, groups within a company must factor user experience in planning. A sales department, for instance, may use a user metric to forecast and/or quantify revenue growth or customer turnover. A business development department may ration capital, seek new partnerships, and/or explore new business lines, all based in terms of users. A marketing department and a product development department may use user demographic data to analyze prospective services, when such services should be launched, and upon whom such services should focus. Though variations and additional details may be included, the central metric used by the business oriented departments may likely be the total number of users.
[0022] For the more technical departments, forecasts, projections and network dimensioning can be based on more technical metrics. Such technical metrics may, in a cellular telecommunications network, traditionally include busy hour call attempts (BHCA), transactions per second (TPS), messages per second (MPS), megabytes used (e.g., memory requirements), octets transmitted/received (e.g., signaling requirements), percent CPU (central processing unit) utilization, and many other metrics. Further, each network service (e.g., voice service, data service, multimedia service, etc.) or network node (e.g., call switching, network maintenance/monitoring, voicemail, etc.) may traditionally involve totally or partially different metrics in terms of the hardware and software required to facilitate the specific service or element. While these various traditional technical metrics can be highly relevant to overall system performance and capacity, they are generally only to those who are trained in a corresponding discipline, and likely will not be immediately understandable to those people on the business side of the company who are trained in other disciplines. Thus, some embodiments of the present invention provide systems and/or methods for capturing the various technical metrics into the single metric of supportable users.
[0023] A network may include many different platforms with multiple nodes, but each platform may share at least the following three elements: memory usage, CPU usage, and signaling link usage. Formulas, based on these and/or other performance constraints and/or relationships are created to express everything in terms of supportable users. Example embodiments determine, for example, the number of bytes of memory used by a user, the percentage of CPU throughput used by a user, and the number of messages (e.g., generated SS7 signals) per user. In a further embodiment, this data then in turn is applied to various network node configurations, which depends on component selection (e.g., server A vs. server B), component aggregation (e.g., two A servers and a B server vs. three A servers), and positioning of network nodes (e.g., the network topology). As a result of this application, each element, node, or package of elements may be expressed in the single metric of supportable users.
[0024] An example of a network component in a GSM (Global System for Mobile communications) cellular telecommunications network, is a home location registrar/authentication center (HLR/AUC). An HLR/AUC may be responsible for maintaining a list of the home location and/or current location of wireless telecommunication handsets (i.e., users) on the network. In a further embodiment, the HLR/AUC is responsible for ensuring each user attempting to use network resources is authorized. FIG. 1 illustrates how this node (HLR/AUC) can be analyzed and utilized in the context of an embodiment of the present invention. At 110 , the example method collects the total number of active users currently associated with a specific platform (e.g., 30,000). At 120 , the example method collects the current utilization (e.g., 50%) for the platform of a network element, or the relevant network platform, (e.g., memory usage). At 125 , the method then returns to collect the current usage for any other constraint that makes up the platform. For example, the method may collect data showing that there are currently 30,000 users utilizing a platform, memory is 50% utilized, CPU is 25% utilized, and signaling links (e.g., SS7) are 48% utilized. At 130 , the maximum supportable users metric is calculated (e.g., 60,000). At 60,000 users, the memory utilization may cap out at 100%. Therefore, regarding the constraints of this network element, the network has a supportable users metric of 60,000. However, that does not necessarily imply that only the highest percent utilization of the several parts is the only relevant number. At 60,000 users, the CPU may be at 50% utilization and signaling may be at 96% utilization. These utilization numbers are, however, only for the one HLR/AUC feature. The HLR/AUC can be coupled with other elements that are very CPU intensive but do not use much memory or signaling capacity.
[0025] Further calculations may be needed for adequate user forecasting and network growth. At 135 , the example method calculates a per node average supportable users metric. For example, 30,000 users may cause the network memory to have a 50% utilization, and there may currently be 30 nodes in the network. A node may be, for example, a kind of server with a specific configuration or a set of servers with a specific configuration. Thus, there may be several different kinds of nodes, and each kind or type of node may need to have a per node supportable users capacity calculated to achieve the most advantageous and/or efficient results. Assuming all 30 nodes are the same, and the network had a 60,000 supportable users capacity, then each node may have a 2,000 average supportable users capacity according to the example embodiment. At 140 , the example method forecasts future user levels (for instance, a sales forecast). In a further or alternative embodiment, the example method imports the forecast from another source. Then at 150 , the example method calculates what node increases will be required to accommodate the growing user forecast.
[0026] As the example method of FIG. 1 illustrates, all network dimensioning (e.g., planning) can be expressed, according to the present invention, in terms of forecasted user levels and maximum supportable users capacity based on a most limiting constraint. As new equipment is used and/or new equipment configurations adopted, the underlying formulas can be adjusted or expanded, and after those adjustments are made, all dimensioning can be expressed in terms of supportable users. This allows for faster, clearer, and far more agile network analysis and planning. Repackaging the capacity metrics into individual node's supportable users capacity and overall network supportable users capacity not only clarifies and streamlines signaling (e.g., SS7), memory, license, and CPU requirements, but physical requirements can be made more clear and more efficient, such as number of racks or shelves, amperage or power consumption, and square meters or floor space. Once the central metric has been established, the business units may propose changes designed to increase users by a certain number. In previous systems/methods, the technical units would have to go through a complicated, time-consuming, and expensive nonautomated review of utilization levels and technical capacity to determine hardware increases necessary to handle the increase. In embodiments of the present invention, network utilization can be expressed in terms of supportable users, and network nodes can be organized under predetermined amounts of additional supportable users. Further, the embodiments of the present invention can be automated. This can allow for extremely agile network planning, understood across company departments.
[0027] FIG. 2 illustrates another example embodiment of the present invention. First, the technical group (e.g., Platform Systems Engineering Teams) 210 decide on or recommend utilization thresholds and capacities (e.g., at 215 ). For example, the engineering teams may acquire the technical specifications for different pieces of hardware and software, each of which may have a different level of technical resources. The engineering teams may find that utilizations tower than 100% cause greater overall system efficiency and recommend an appropriate utilization threshold. At 220 , these capacity constraints and utilization thresholds are expressed as total supportable users. At 230 , the business (e.g., non-technical) teams provide historical data about users (e.g., at 235 ). At 240 , this historical data help provides user/platform demand forecast trends. In addition to the utilization thresholds and capacities outlined in 215 , the engineering teams may also provide rule sets and model specifications for new or prospective equipment (e.g., at 255 ). This can be for any number of things, including changes to the legacy systems, additions to the legacy systems, or new model systems to augment, replace, or supplement the legacy systems. These specifications can then be used to determine the purchasing requirements for the user based dimensioning at 260 . At 270 , the individual network node requirements are determined based on the user based model just assembled, which may result in 275 , a platform budget designed to meet the user based forecasting predictions. Once the user based dimensioning results are agreed upon (e.g., at 280 ), the regional planning teams can plan floor space and other physical infrastructure requirements at 285 for the approved additions.
[0028] FIG. 3 illustrates an example node according to example embodiments of the present invention. Node 310 includes three components 311 , 312 , and 313 . These components can be servers (e.g., a rack of blade servers) that are jointly responsible for the processing functions of the network node 310 , or they can each have a dedicated set of tasks partitioned or partially partitioned from the other tasks on the other servers. There may be more or fewer than three components to each node, and the components themselves may be made of individual entities. Each component can have a current utilization monitor, e.g., 311 a, 312 a, and 313 a. The node can also have a user level monitor 320 . The utilization monitors and user level monitor interface with a component 350 configured to calculate a maximum supportable users capacity level based on the data from the other monitors.
[0029] FIG. 4 illustrates an example network according to example embodiments of the present invention. For example, network 400 is made up for four nodes, 410 , 420 , 430 , and 440 . Each of these nodes can be like the node illustrated in FIG. 3 without the monitor components shown. If, for example, the maximum supportable users capacity level component 350 determined that the maximum number of users that a node could facilitate was 10,000, then, according to an embodiment of the present invention, network 400 could currently support 40,000 users. Connected to the network 400 can be a user forecaster component 490 . This forecaster component 490 receives, for example, historical user data 495 . This data may come from within network 400 or may come from an outside source. In an embodiment, the forecaster may use other pieces of data (e.g., the component utilization constraints) in determining estimated future user levels. In an embodiment, when the forecaster component indicates that the level of users will exceed the maximum user capacity, the network (or network administrators) add a preconfigured network node 450 , which has a predetermined supportable users capacity associated with it. New node 450 may be the same or different than any of nodes 410 , 420 , 430 , or 440 . Additionally, the supportable users associated with node 450 may be determined based on historical data of identical or similar nodes already in operation. In a further or alternative embodiment, the supportable users of new node 450 may be determined by the factory specifications of each of the components that make up node 450 .
[0030] It will be appreciated that all of the disclosed methods and procedures described herein can be implemented using one or more computer programs or components. These components may be provided as a series of computer instructions on any conventional computer-readable medium, including RAM, ROM, flash memory, magnetic or optical disks, optical memory, or other storage media. The instructions may be configured to be executed by a processor which, when executing the series of computer instructions, performs or facilitates the performance of all or part of the disclosed methods and procedures.
[0031] It should be understood that there exist implementations of other variations and modifications of the invention and its various aspects, as may be readily apparent to those of ordinary skill in the art. The scope of the invention is not limited by specific embodiments described herein. Features and embodiments described above may be combined with each other in various combination. | A system and method are provided for converting individual technical metrics into a single relevant metric understood and accepted by both technical and non-technical components of a business venture. An example system and/or method includes measuring current technical utilizations and capacities, translating those into a supportable users metric, forecasting future utilization levels, translating those into future network component and/or hardware requirements, and expanding/scaling technical capacity based on those values and the predetermined capacity levels of additional components and/or hardware. | 7 |
This is a continuation-in-part application of U.S. application Ser. No. 13/415,185, filed Mar. 8, 2012. The application claims the benefit of U.S. provisional application Ser. No. 61/609,376, filed Mar. 12, 2012, the subject matter of which is incorporated herein by reference
FIELD OF THE INVENTION
The present invention relates to a nonvolatile memory, and more particularly to a method of fabricating an erasable programmable single-poly nonvolatile memory.
BACKGROUND OF THE INVENTION
FIG. 1 is a schematic cross-sectional view illustrating a conventional programmable dual-poly nonvolatile memory. The programmable dual-poly nonvolatile memory is also referred as a floating-gate transistor. As shown in FIG. 1 , this nonvolatile memory comprises two stacked and separated gates. The upper gate is a control gate 12 , which is connected to a control line C. The lower gate is a floating gate 14 . In addition, an n-type doped source region and an n-type doped drain region are constructed in a P-substrate. The n-type doped source region is connected to a source line S. The n-type doped drain region is connected to a drain line D.
In a case that the nonvolatile memory is in a programmed state, a high voltage (e.g. +16V) is provided by the drain line D, a ground voltage is provided by the source line S, and a control voltage (e.g. +25V) is provided by the control line C. Consequently, during the electrons are transmitted from the source line S to the drain line D through an n-channel region, the hot carriers (e.g. hot electrons) are attracted by the control voltage on the control gate 12 and injected into the floating gate 14 . Under this circumstance, a great number of carriers are accumulated in the floating gate 14 . Consequently, the programmed state may be considered as a first storage state (e.g. “0”).
In a case that the nonvolatile memory is in a non-programmed state, no carrier is injected into the floating gate 14 , and thus the non-programmed state may be considered as a second storage state (e.g. “1”).
In other words, the characteristic curves of the drain current (id) and the gate-source voltage (Vgs) (i.e. an id-Vgs characteristic curve) in the first storage state and the id-Vgs characteristic curve in the second storage state are distinguished. Consequently, the storage state of the floating-gate transistor may be realized according to the variation of the id-Vgs characteristic curve.
However, since the floating gate 14 and the control gate 12 of the programmable dual-poly nonvolatile memory should be separately produced, the process of fabricating the programmable dual-poly nonvolatile memory needs more steps and is incompatible with the standard CMOS manufacturing process.
U.S. Pat. No. 6,678,190 discloses a programmable single-poly nonvolatile memory. FIG. 2A is a schematic cross-sectional view illustrating a conventional programmable single-poly nonvolatile memory disclosed in U.S. Pat. No. 6,678,190. FIG. 2B is a schematic top view illustrating the conventional programmable single-poly nonvolatile memory of FIG. 2A . FIG. 2C is a schematic circuit diagram illustrating the conventional programmable single-poly nonvolatile memory of FIG. 2A .
Please refer to FIGS. 2A-2C . The conventional programmable single-poly nonvolatile memory comprises two serially-connected p-type metal-oxide semiconductor (PMOS) transistors. The first PMOS transistor is used as a select transistor, and a select gate 24 of the first PMOS transistor is connected to a select gate voltage V SG . A p-type doped source region 21 is connected to a source line voltage V SL . Moreover, a p-type doped drain region 22 may be considered as a combination of a p-type doped drain region of the first PMOS transistor and a first p-type doped region of the second PMOS transistor. A floating gate 26 is disposed over the second PMOS transistor. A second p-type doped region 23 of the second PMOS transistor is connected to a bit line voltage V BL . Moreover, these PMOS transistors are constructed in an N-well region (NW). The N-well region is connected to an N-well voltage V NW . The second PMOS transistor is used as a floating gate transistor.
By properly controlling the select gate voltage V SG , the source line voltage V SL , the bit line voltage V BL and the N-well voltage V NW , the conventional programmable single-poly nonvolatile memory may be operated in a programmed state or a read state.
Since the two PMOS transistors of the conventional programmable single-poly nonvolatile memory have respective gates 24 and 26 , the process of fabricating the conventional programmable single-poly nonvolatile memory is compatible with the standard CMOS manufacturing process.
As described in FIGS. 1 and 2 , the nonvolatile memory is programmable. The electrical property of the nonvolatile memory is only utilized to inject a great number of hot carriers to the floating gate. However, the electrical property fails to be utilized to remove the carriers from the floating gate. That is, for achieving the data-erasing function, the carriers stored in the floating gate may be removed from the floating gate by exposing ultraviolet (UV) light to the nonvolatile memory. These nonvolatile memories are named as one time programming (OTP) memories.
Therefore, for multi-times programming (MTP) memories design, there is a need of providing an erasable programmable single-poly nonvolatile memory.
SUMMARY OF THE INVENTION
The present invention provides a method of fabricating an erasable programmable single-poly nonvolatile memory in order to obviate the drawbacks encountered from the prior art.
The present invention provides a method of fabricating an erasable programmable single-poly nonvolatile memory, comprising steps of: forming a gate oxide layer of a floating gate transistor; defining a first portion of the gate oxide layer above a channel region of the floating gate transistor, wherein the first portion of the gate oxide layer are injected by a plurality of carriers during a programmed state; defining a second portion of the gate oxide layer, wherein the second portion of the gate oxide layer are ejected by the carriers during an erase state; and covering a polysilicon gate on the gate oxide layer; wherein, a thickness of the first portion of the gate oxide layer is different from a thickness of the second portion of the second gate oxide layer.
The present invention provides a method of fabricating an erasable programmable single-poly nonvolatile memory, comprising steps of: defining a first area and a second area in a first type substrate; forming a second type well region in the first area; forming a first gate oxide layer and a second gate oxide layer covered on a surface of the first area, wherein the second gate oxide layer is extended to and is adjacent to the second area; forming a DDD region in the second area; etching a portion of the second gate oxide layer above the second area; forming two polysilicon gates covered on the first and the second gate oxide layers; and defining a second type doped region in the DDD region and a first type doped regions in the second type well region.
Numerous objects, features and advantages of the present invention will be readily apparent upon a reading of the following detailed description of embodiments of the present invention when taken in conjunction with the accompanying drawings. However, the drawings employed herein are for the purpose of descriptions and should not be regarded as limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which:
FIG. 1 (prior art) is a schematic cross-sectional view illustrating a conventional programmable dual-poly nonvolatile memory;
FIG. 2A (prior art) is a schematic cross-sectional view illustrating a conventional programmable single-poly nonvolatile memory disclosed in U.S. Pat. No. 6,678,190;
FIG. 2B (prior art) is a schematic top view illustrating the conventional programmable single-poly nonvolatile memory of FIG. 2A ;
FIG. 2C (prior art) is a schematic circuit diagram illustrating the conventional programmable single-poly nonvolatile memory of FIG. 2A ;
FIGS. 3A˜3D schematically illustrate an erasable programmable single-poly nonvolatile memory according to an embodiment of the present invention;
FIG. 4 illustrates the standard CMOS process for manufacturing the erasable programmable single-poly nonvolatile memory of the present invention;
FIG. 5A˜5H shows the steps of manufacturing the erasable programmable single-poly nonvolatile memory according to the standard CMOS process;
FIG. 6 is a plot illustrating the relation of the thickness of the gate oxide layer and the erase line voltage (V EL ).
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 3A˜3D schematically illustrate an erasable programmable single-poly nonvolatile memory according to an embodiment of the present invention. FIG. 3A is a schematic top view illustrating the erasable programmable single-poly nonvolatile memory according to the embodiment of the present invention. FIG. 3B is a schematic cross-sectional view illustrating the erasable programmable single-poly nonvolatile memory of FIG. 3A and taken along a first direction (a 1 -a 2 ). FIG. 3C is a schematic cross-sectional view illustrating the erasable programmable single-poly nonvolatile memory of FIG. 3A and taken along a second direction (b 1 -b 2 ). FIG. 3D is a schematic equivalent circuit diagram of the erasable programmable single-poly nonvolatile memory according to the embodiment of the present invention.
As shown in FIGS. 3A and 3B , the erasable programmable single-poly nonvolatile memory of the embodiment comprises two serially-connected p-type metal-oxide semiconductor (PMOS) transistors. These two PMOS transistors are constructed in an N-well region (NW). Three p-type doped regions 31 , 32 and 33 are formed in the N-well region (NW). In addition, two polysilicon gates 34 and 36 are spanned over the areas between the three p-type doped regions 31 , 32 and 33 , and gate oxides layer 342 and 362 are formed between the two polysilicon gates 34 and 36 and a top surface of the substrate.
The first PMOS transistor is used as a select transistor, and the polysilicon gate 34 (also referred as a select gate) of the first PMOS transistor is connected to a select gate voltage V SG . The p-type doped region 31 is a p-type doped source region and connected to a source line voltage V SL . The p-type doped region 32 is a p-type doped drain region, which may be considered as a combination of a p-type doped drain region of the first PMOS transistor and a first p-type doped region of the second PMOS transistor. The polysilicon gate 36 (also referred as a floating gate) is disposed over the second PMOS transistor. The p-type doped region 33 is a second p-type doped region of the second PMOS transistor and connected to a bit line voltage V BL . Moreover, the N-well region (NW) is connected to an N-well voltage V NW . The second PMOS transistor is used as a floating gate transistor.
As shown in FIGS. 3A and 3C , the erasable programmable single-poly nonvolatile memory of the embodiment comprises an n-type metal-oxide semiconductor (NMOS) transistor or a combination of the floating gate 36 , gate oxide layer 362 and an erase gate region 35 . The NMOS transistor is constructed in a P-well region (PW). A double diffused drain (DDD) region 37 is formed between an n-type doped region 38 and a P-well region (PW). In other words, the erase gate region 35 includes the P-well region (PW), the double diffused drain (DDD) region 37 and the n-type doped regions 38 .
As shown in FIG. 3A , the floating gate 36 is extended to and is adjacent to the erase gate region 35 . Moreover, a combination of the n-type doped region 38 and the DDD region 37 may be considered as a combination of an n-type doped source region and an n-type doped drain region of the NMOS transistor and the floating gate 36 may be considered as a gate of the NMOS transistor. The n-type doped region 38 is connected to an erase line voltage V EL . In addition, the P-well region (PW) is connected to a P-well voltage V PW . As shown in FIG. 3C , the gate oxide layer 362 is formed under the floating gate 36 , and the gate oxide layer 362 includes two portions 362 a and 362 b . The first portion 362 a of the gate oxide layer 362 is formed in the floating gate transistor (second PMOS transistor) and the second portion 362 b of the gate oxide layer 362 is formed in the NMOS transistor (or above the erase gate region 35 ). According to the embodiment of the present invention, a thickness of the first portion 362 a of the gate oxide layer 362 is thicker than a thickness of the second portion 362 b of the gate oxide layer 362 . Furthermore, a shallow trench isolation (STI) structure 39 is formed between the P-well region (PW) and the N-well region (NW).
FIG. 4 illustrates the standard CMOS process for manufacturing the erasable programmable single-poly nonvolatile memory of the present invention. These processes include STI formation (S 402 ), N-well formation (S 404 ), IO gate oxide layer formation (S 406 ), N-DDD implantation (S 408 ), P-well formation (S 410 ), IO gate etching back process (S 412 ), poly gate formation (S 414 ), and doped region definition (S 416 ).
FIG. 5A˜5H shows the steps of manufacturing the erasable programmable single-poly nonvolatile memory according to the standard CMOS process. Because the main feature of the present invention is the erase gate region, only the top view and the cross-sectional view taken along the (b 1 -b 2 ) direction are shown.
According to the top view in FIG. 5A , two separate areas (A and B) are defined in p-substrate after the STI formation process. According to the cross-sectional view in FIG. 5A , STI structures 39 are embedded in p substrate. According to the present invention, two serially-connected PMOS transistors will be formed in area A and the erase gate region will be formed in area B.
In the N-well formation process, only the area A is exposed and a N-well implantation process is performed. According to the top view and the cross-sectional view in FIG. 5B , an N-well region (NW) is formed in p-substrate.
In the IO gate oxide layer formation process, two gate oxide layers 342 and 362 are formed on the surface of the substrate for two serially-connected PMOS transistors. Furthermore, the gate oxide layer 362 is extended to and is adjacent to the area B.
As shown in FIG. 5D , in the N-DDD implantation step, a mask layer, for example a photoresist (PR) mask layer or a SiN hard mask layer, is formed and only the area B is exposed and the other area is protected by a mask layer. And then, an N-DDD implantation process is performed. According to the cross-sectional view in FIG. 5D , a DDD region 37 is formed in p-substrate after the N-DDD implantation step.
After the N-DDD implantation process, the same mask layer used in the N-DDD implantation step is used again for the P-well formation process. According to the cross-sectional view in FIG. 5E , a P-Well region (PW) is formed under the DDD region 37 . Because the p substrate has the same type with the P-well region (PW), the P-well formation process could be optionally performed.
After the P-well formation process, the same mask layer still is used again for the IO gate etching back process. According to the cross-sectional view in FIG. 5F , a first portion 362 a of the gate oxide layer 362 protected by the mask layer is not etched and a second portion 362 b of the gate oxide layer 362 not protected by the mask layer is etched to have a thinner thickness than the first portion 362 a . According to the present invention, a short loop feedback system by monitoring a pattern on the substrate is used to exactly etch the gate oxide layer 362 .
After removing the mask layer 368 , a poly gate formation process is proceeded. As shown in FIG. 5G , two polysilicon gates 34 and 36 are covered on the two gate oxide layers 362 and 342 after the poly gate formation process.
In the doped region definition process, a formation of n-type doped region and a formation of p-type doped region are separately performed. As shown in FIG. 5H , an n-type doped region 38 is formed in the DDD region 37 and the erase gate region is formed. Also, three p-type doped region 31 32 and 33 are formed in the NW region and the two serially-connected PMOS transistors are formed. Therefore, the erasable programmable single-poly nonvolatile memory of the present invention is manufactured.
FIG. 6 is a plot illustrating the relation of the thickness of the gate oxide layer and the erase line voltage (V EL ). In standard CMOS manufacturing process, thickness of the gate oxide layer 362 of 5V IO device is about 13 nm and the erase line voltage (V EL ) is about 15-16V to remove the storage carriers from the floating gate 36 . However, the higher erase line voltage (V EL ) may result in junction breakdown and high ERS power in the erase gate region 35 . According to the embodiment of the present invention, a portion (second portion 362 b ) of the gate oxide layer 362 is further etched to have a thinner thickness (about 7 nm) then the first portion 362 a . Here, the erase line voltage (V EL ) will be about 10V˜11V.
In the programmed state, the hot carriers (e.g. electrons) are transmitted through a channel region of the floating gate transistor corresponding to the floating gate 36 , the first portion 362 a of gate oxide layer 362 are tunneled by the hot electrons and then the hot electrons are injected into the floating gate 36 . In the erased state, the second portion 362 b of gate oxide layer 362 are tunneled by the storage carriers in the floating gate 36 and then the storage carriers are discharged out of the nonvolatile memory through the n-type doped region 38 and the DDD region 37 . That is to say, a thickness of the first portion 362 a for the hot electrons injected into the floating gate 36 is thicker than a thickness of the second portion 362 b for storage carriers ejected from the gate oxide 36 .
From the above description, the erasable programmable single-poly nonvolatile memory of the present invention is capable of decreasing the erase line voltage (V EL ). That is, by providing a lower erase line voltage V EL , storage state of the nonvolatile memory of the present invention is changed.
While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures. | The present invention provides a method of fabricating an erasable programmable single-poly nonvolatile memory, comprising the steps of: defining a first area and a second area in a first type substrate; forming a second type well region in the first area; forming a first gate oxide layer and a second gate oxide layer covering a surface of the first area, wherein the second gate oxide layer extends to and is adjacent to the second area; forming a DDD region in the second area; etching a portion of the second gate oxide layer above the second area; forming two polysilicon gates covering the first and the second gate oxide layers; and defining a second type doped region in the DDD region and defining first type doped regions in the second type well region. | 7 |
RELATED PATENT APPLICATIONS
The present application claims priority to provisional application U.S. Ser. No. 60/714,704, filed 7 Sep. 2005, entitled “Power Cinching Striker”. The present application is related to U.S. patent application Ser. No. 11/247,800, entitled “Power Linear Displacement Striker”, filed on even date herewith and owned by a common assignee of interest.
TECHNICAL FIELD
The present invention, although useful in other applications, relates to an active door latch assembly which ensures easy and reliable final closure of a vehicle door by moving the striker toward the center of the vehicle body when the vehicle door is about to be fully closed and moving the striker away from the center of the vehicle body when the vehicle door is in the process of being opened. More particularly, the present invention relates to an improved active door latch assembly, which can operate more reliably and cost effectively than was possible heretofore.
BACKGROUND OF THE INVENTION
A final closing device for a closure member on a vehicle body, and more particularly, a device for moving a vehicle-mounted closure member (e.g., a sliding door, a hinged door, a hood, a trunk lid, or the like) from a nearly closed position, at which a latch bolt or member engages a striker, to a fully closed position, at which the closure member is sealingly engaged with the vehicle body, is well known.
A typical standard automotive door latch striker assembly includes a striker, which can take the form of a pin, a U-shaped member or the like, fixedly mounted in the door frame to project into the door opening and into the path of movement of a latch member mounted on the edge of the door, which includes a fork bolt therein. The latch member is typically movably mounted with respect to the door and arranged so that as the door approaches its closed position, the latch member will engage the striker and further closing movement of the door will move the latch member into a safety latch position with respect to the pin, sometimes referred to as the secondary latch position, and further closing movement of the door will move the latch member into a primary latch position with respect to the pin, which positively retains the door against movement away from its closed position. It is generally known for at least part of the movement of the latch member into latched relationship with the striker to be resisted by a spring, and many users of sliding doors of this type habitually close the door with far greater force than necessary to overcome the spring bias. Greater force is generally required in the case of sliding doors, such as those employed in vans, where movement of the door through the final phase of movement to the fully closed position must encompass a resilient door seal, which extends around the entire periphery of the door opening.
Power striker devices have been proposed to overcome the high force requirements to move sliding doors into the fully closed position. Typically the power striker devices are mounted on the door frame for powered movement between an outboard ready position with respect to the vehicle center line, where the latch is engaged with the striker, and an inboard holding position, where the striker holds the latch in the fully closed position. It is still required in such systems to use high force or momentum in order to ensure that the latch engages the striker in the primary latch position prior to movement into the fully closed position. When the door is open, the striker is located in its outboard ready position. After closing translation of the door is complete, the latch on the door engages the striker and latches the door to the striker while the striker is still in the outboard position. The door may engage a limit switch on the door frame when in the outboard position or may be sensed by a position sensor on the translator, which is a separate motor which drives the door between its relative positions, to actuate a drive motor which, through appropriate mechanism, drives the striker to its inboard position, such that the latched engagement between the door and striker enables the pin to drive the door to the fully closed position. With this arrangement, a closing force sufficient to engage the latch to the primary latch position with respect to the striker needs to be applied. The powered movement of the striker provides the force necessary to compress the door seal. If the striker and latch do not reach the primary latch position with respect to one another, the powered movement of the striker from its outboard position to its inboard position would not be sufficient to bring the door to the fully closed position in sealed engagement with the frame around the periphery of the door opening. In such cases, the user may be required to reopen and close the door repeatedly until the latch and striker are disposed in the primary latch position with respect to each other when in the outboard position.
For the purpose of preventing the intrusion of rain water and so on, a seal member, which is molded typically from synthetic rubber and is generally called weather strip, is interposed in a gap between a door and an associated vehicle body. Recently, with the aim of reducing the wind noise and noises from air leakage in addition to improving the sealing effect, weather strips of higher reaction force or, in other words, weather strips having higher elastic coefficients are being preferred. This high reaction force tends to prevent a full latching of the door latch upon closing of the door and may cause only a partially closed state of the door. Therefore, it is sometimes necessary to forcibly close the door to overcome the reaction force of the weather strip and to obtain a fully latched state of the door latch. However, when the door is forcibly closed, the sound thereof and the resulting sudden change in the cabin pressure may cause discomfort to the passenger.
To resolve this problem, it is conceivable to move a striker, by a suitable means, which is mounted to the vehicle body to engage with a latch assembly mounted to the door to keep the door closed. Specifically, the striker may be placed at an outward position in advance so as to achieve a latching before the reaction force of the weather strip starts acting upon the door and, after the door latch assembly is fully latched to the striker, the striker is positively driven to a position which causes complete deformation of the weather strip for sufficient sealing effect and complete closure of the door.
However, in order to pull in the striker from its latched position against the reaction force of the weather strip, an extremely strong force is necessary. Suitable actuators for driving the striker are difficult to package and install in the limited space in the interior of the associated body panel structure. It is particularly difficult to package such a drive device in the center pillar of a four-door passenger vehicle.
The final closing systems employed in prior art examples are generally large, costly, complicated mechanisms which are difficult to install, repair and/or replace and have frequently proven to be unsatisfactory in terms of long term performance and reliability. Furthermore, modifying striker actuators for varying applications and vehicle configurations typically requires major redesign and retooling.
Known power striker systems which are designed for flexibility of application tend to be underpowered, resulting in slow operation and a tendency to stall. Furthermore, if their design is not robust, the mechanism can be easily damaged by slamming of the door.
A particular problem common to existing power striker systems stems from the arcuate path of travel of the striker as it traverses from the presented or deployed position to cinched or closed position. This is problematic inasmuch as the mating latch assembly must be able to maintain secure interconnection with the striker as it traverses vertically and/or longitudinally as well as inwardly. In a related problem, electrically driven systems do not have adequate redundancy and can fail without the door being in the fully closed and positively latched condition.
It is, therefore, a primary object of the present invention to provide an improved final closing device for closure members of vehicles which overcomes known shortfalls of existing devices without adding to part count, manufacturing complexity or cost.
SUMMARY OF THE INVENTION
Generally, the present invention fulfills the forgoing needs by providing, in one aspect thereof, a compact, power cinching striker, which allows for linear motion of the striker pin while the supporting striker plate rotates about the striker pins pivot point.
In another aspect, the present invention provides a loss of power over-ride feature enabling cinching without power when presented with normal manual operation of the vehicle closure system.
The presently inventive power striker assembly operates to effect final positioning of a closure member on an associated vehicle and includes a fixed frame which is adapted for attachment to the host vehicle at a location adjacent the closure member, a striker member which is positionable to selectively engage a mating latch mechanism carried by the closure member and acts to displace the closure member from an extended or open position to a retracted or closed position. The striker member is carried by a striker plate which is interconnected with the fixed frame by guide means that effects simultaneous translational and rotational displacement of the striker plate between first and second end limits of travel resulting in substantially linear displacement of the striker member between the extended and retracted positions. Finally, actuator means is provided to selectively displace the striker plate between its end limits of travel. This arrangement ensures true linear translation of the striker pin or member, simplifying the design of its interface with the mating latch assembly and enhancing operational performance. Furthermore, the depicted simplified design allows for a stackable assembly process to enhance quality while reducing investment. Also, the cinching striker design is compact and flexible enough to function in numerous vehicle applications in a cost effective manner.
According to another aspect of the invention, the guide means includes first and second bushings carried with the frame which are in respective continuous sliding engagement with first and second guide surfaces throughout transition of the striker plate between its end limits of travel. Furthermore, the striker plate is substantially flat and displaceable within a two-dimensional plane defined by the frame. This arrangement has the advantage of providing an extremely compact yet robust mechanism able to withstand high overload conditions.
According to another aspect of the invention, sensor means are provided to sense the position of the striker plate, and thus, the striker member, and to provide a feedback signal to the actuator. This arrangement has the advantage of effecting precise control of the power striker assembly.
According to still yet another aspect of the invention, a uni-directional permanent magnet motor is employed to effect both cinching and presenting striker member displacement during such one directional operation. This arrangement has the advantage of an extremely simple, low cost design.
These and other features and advantages of this invention will become apparent upon reading the following specification, which, along with the drawings, describes preferred and alternative embodiments of the invention in detail.
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 , is a broken, sectional view of the preferred embodiment of a power cinching striker assembly embodying the present invention in application providing final closure of a sliding side door of a motor vehicle;
FIG. 2 , is an exploded, perspective view of the preferred power cinching striker assembly of FIG. 1 ;
FIG. 3 is a front perspective view of the power cinching striker assembly of FIG. 1 ;
FIG. 4 , is a cross-sectional view of the power cinching striker assembly taken on lines 4 - 4 of FIG. 3 , on an enlarged scale;
FIG. 5 , is a cross-sectional view of the power cinching striker assembly taken on lines 5 - 5 of FIG. 3 , on an enlarged scale, illustrating the striker and striker plate disposed in the presented position;
FIG. 6 , is a cross-sectional view of the power cinching striker assembly similar to FIG. 5 , but with the striker and striker plate disposed in a latched position;
FIG. 7 , is a cross-sectional view of the power cinching striker assembly similar to FIG. 5 , but with the striker and striker plate disposed in an intermediate position between the cinched and presented positions as a result of being manually overriden;
FIG. 8 is a cross-sectional view of the power cinching striker assembly similar to FIG. 5 , but with the striker and striker plate disposed in the latched position as a result of being manually overridden;
FIG. 9 , is a front perspective view of a simplified alternative embodiment of the inventive power cinching striker assembly;
FIG. 10 , is a back perspective view of the alternative power cinching striker assembly of FIG. 9 ; and
FIG. 11 , is a partial broken front plan view of the power cinching striker assembly of FIG. 8 , on an enlarged scale.
Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention. The exemplification set forth herein illustrates an embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is intended for application in varied automotive vehicle applications and will be described in that context. It is to be understood, however, that the present invention could also be successfully applied in many other applications. Accordingly, the claims herein should not be deemed limited to the specifics of the preferred embodiment of the invention described hereunder.
Referring to FIG. 1 , a power cinching striker assembly 10 is illustrated installed within its preferred environment of a motor vehicle 12 . Vehicle 12 defines a body 14 and at least one movable panel or closure member 16 attached to and carried by the body 14 via hinges, pivots, guide tracks or the like for translation between open and closed positions. In the illustrated embodiment of the invention, the striker assembly 10 is installed within a van-type vehicle including a sliding side door and will be described in that context. However, it is contemplated that the present invention can be employed with equal success in other applications and with other types of closure members such as hinged doors, lift gates, windows, trunk lids, hoods and various access panels.
FIG. 1 is a schematic diagram, as viewed from above, of a portion of an opening 18 in vehicle 12 for receiving closure member 16 . A number of details are deleted or simplified for the sake of clarity, it being understood that the basic structure, operation and guide support of a van sliding door is well known.
In application, closure member 16 can assume three distinct positions, as well as any number of transitional intermediate positions. When in a fully open position (not illustrated) closure member 16 is displaced from opening 18 to provide user access to the interior of the vehicle 12 . As illustrated in FIG. 1 , closure member 16 is substantially registered with its associated opening 18 . Closure member 16 is depicted in solid line in a “presented” or “pre-latched” position, and in phantom in a “closed” or “cinched” position.
The portion of closure member 16 illustrated in FIG. 1 has a jamb face 20 co-acting with an internal structural member 22 to define a cavity 24 containing a latch 26 of conventional design. Latch 26 is disposed adjacent an opening 28 in jamb face 20 facing an adjacent wall 30 of body 14 defining opening 18 . A weather strip or seal 32 is affixed to a convex wall surface 34 outboard of jamb face 20 and extends around the entire periphery of closure member 16 .
Referring to FIGS. 1 and 3 , power cinching striker assembly 10 comprises a housing assembly 36 , which sealingly encloses all of its internal components. A striker member 38 depends outwardly from and is actively supported by housing assemble 36 . Housing assembly 36 is fixedly mounted to the inner surface of the wall 30 defining closure member opening 18 , with striker member 38 extending outwardly through an elongated opening 40 in wall 30 . Striker member further extends through opening 28 of closure member 16 and into cavity 24 to engage latch 26 . Although not illustrated, it is contemplated that a decorative and protective elastomeric seal can be employed to close opening 40 to prevent intrusion of water and environmental contaminates but without interfering with reciprocating displacement of striker member 38 .
Striker member 38 is preferably “u” shaped, consisting of a first or striker leg 42 , a second or support leg 44 and an interconnecting bridge portion 46 . Definitionally, for purposes of interpretation of the claims, the striker leg 42 is a “striker member”, and the second leg 44 and bridge member 46 are non-functional, other than providing structural support. As an alternative, striker member 38 could be replaced by a single cantilever striker pin.
When closure member 16 is manually moved or power driven from a fully or partially open position into its illustrated presented position, inertia of the moving closure member 16 will cause the latch 26 to contact and self-engage with the striker leg 42 or striker member 38 . Simultaneously, an inner surface of closure member 16 will contact and displace the plunger 48 of a door switch 50 , which is fixedly secured to a suitable place in the side surface or wall 30 of opening 18 . Plunger 48 is biased outwardly by a spring (not illustrated) and operates to change the conductive state of internal electrical contacts (not illustrated) interconnected with a control circuit 52 by lead wires 54 . Control circuit 52 is also electrically in-circuit with power striker assembly 10 through intermediate control lines 56 .
Control circuit 52 can be integrated into the body computer of the host vehicle 12 or be stand-alone. Control circuit 52 includes a power source for selectively electrically energizing the power striker assembly.
Door switch 50 preferably contains a plurality of normally open or normally closed contact pairs, which provide a closure member position signal to control circuit 52 via lead wires 54 . It is further contemplated that the mechanism (not illustrated) with the latch 26 can operate under electrical or manual control, which may include position sensors. The outputs of such sensors could be used to provide additional inputs to control circuit 52 .
Whenever the closure member 16 is in a partially or fully opened position (not illustrated), control circuit 52 has previously provided a control signal via lines 56 to effect positioning of striker member 38 in its illustrated (solid line) presented or pre-latch position in FIG. 1 . When the closure member 16 is displaced to its illustrated (solid line) presented position and striker member 38 engages latch 26 , plunger 48 of door switch 50 is partially depressed, causing control circuit 52 to send a control signal to the power striker assembly 10 which will translate the striker member 38 from its solid line position to its phantom position. Insodoing, the striker member will draw the latch 26 , as well as the illustrated portion of the closure member 16 , inwardly to its illustrated (in phantom) cinched or closed position, a dimension designated by arrow T. This translation compresses the seal 32 about the periphery of the closure member 16 to effect a substantially water tight seal.
The power cinching striker assembly 10 described herein has proven to be an extremely robust, utilitarian design. For example, one particular design provides 6.0-10.0 mm of linear striker pin displacement and is capable of cinching up to 1200 N of force at various temperature and environmental extremes. The high efficiency of the design results in an actuation time of less than 2.0 seconds to displace the striker pin linearly 6.0 mm when under load. The design is extremely flexible and can be easily and inexpensively modified to accommodate various load profiles required for specific vehicle seal force requirements.
As will described herein below, the preferred power cinching striker design allows for linear motion of the latching pin while the striker plate rotates about its pivot points. This effectively eliminates undesirable striker pin non-linear translation associated with prior art designs. This simplified design allows for variable striker pin positioning relative to the main footprint of the mechanism without sacrificing the linear displacement mentioned above. This results in a design, which can be tailored towards both lift gate and sliding door applications.
Referring to FIGS. 1 and 2 , the internal details of the various structural components of the power cinching striker assembly are illustrated. Housing assembly 36 comprises upper and lower housing portions 58 and 60 , respectively, which are preferably molded of thermoplastic material and a generally planer cover plate 62 , which is preferably formed of mild steel, underlying the lower surface of lower housing 60 . Housing portions 58 and 60 enclose the below described components, with the exception of the striker member 38 , which extends downwardly through registering elongated openings 64 and 66 formed in lower housing portion 60 and cover plate 62 , respectively. Cover plate 62 serves to structurally reinforce striker assembly 10 and provides a robust mounting surface to the wall 30 of opening 18 of vehicle 12 . Openings 64 and 66 of striker assembly 10 are registered with opening 40 in wall 30 to permit the non-interfering through passage of the striker member 38 in both its cinched and presented positions. Housing portions 58 and 60 and cover plate are retained in assembly by suitable fastener means such as screws 68 .
A substantially flat, sector shaped, elongated striker plate 70 is disposed parallel to and adjacent the upper surface of the bottom wall 72 of lower housing portion 60 . As will be described in greater detail herein below, striker plate 70 is mounted for limited simultaneous translation and rotation between first and second end limits of travel in an imaginary two-dimensional plane parallel to the bottom wall 72 of lower housing portion 60 . A first elongated slot 74 extends through striker plate 70 adjacent its apex. The first slot 74 has a characteristic line of elongation extending generally parallel to the line of elongation of the striker plate 70 . A second, crescent shaped elongated slot 76 extends through striker plate 70 at the opposite (hereinafter “enlarged”) end thereof. The second slot has a characteristic line of elongation substantially offset from the line of elongation of the first slot 74 .
Legs 42 and 44 of striker member 38 extend through spaced through holes 78 and 80 , respectively, and are permanently affixed thereto such as by peening or swedging. As assembled, striker plate 70 and striker member 38 function as a single unitary structure.
A first elongated bushing 82 is fixedly disposed within the first elongated slot 74 for displacement with striker plate 70 . A second elongated bushing 84 is fixedly disposed within the second elongated slot 76 for displacement with striker plate 70 . A first headed cylindrical bearing 86 extends downwardly through bushing 82 and is affixed with bottom wall 72 of lower housing portion 60 and cover plate 62 via registering through passages 88 and 89 , respectively. Likewise, a second bearing 90 , which is integrally formed as part of a stepped drive axle 92 , extends downwardly through bushing 84 and is affixed with bottom wall 72 of lower housing portion 60 and cover plate 62 via registering through passages 94 and 95 , respectively. Thus assembled, striker plate is held in assembly with lower housing portion 60 and is limited to the above-described simultaneous translational and rotational two-dimensional displacement between first and second limits of travel.
A roller bearing 96 is carried for rotation on a headed rivet pin 98 through an intermediate roller pin bushing. Rivet pin 98 is press fit within a registering through passage 101 formed in striker plate 70 spaced from one end of bushing 84 . As will be described herein below, bearing 96 is free to rotate about pin 98 and is carried for translation with striker plate 70 , functioning as a cam follower.
A compression spring 102 has one end affixed to an edge of striker plate 70 via an integral tang feature 104 and the opposed end bearing against an abutment surface 106 integrally formed within lower housing portion 60 . Spring 102 serves to continuously urge striker plate 70 counter-clockwise as viewed in FIG. 2 , towards a limit of travel corresponding with the striker member 38 being in the presented position.
Striker plate 70 end of travel position retention is effected by a detent lever or pawl 108 disposed adjacent the enlarged end of the striker plate 70 . Detent lever 108 is disposed to be co-planer with striker plate 70 and has one end thereof pivotally affixed to the bottom wall 72 of lower housing portion 60 via a detent stud 110 . Detent lever 108 and the adjacent side wall of striker plate 70 define cooperating ramp and abutment surfaces to effect certain latch and detent functionality which will be described herein below.
A detent torsion spring 112 has a loop portion concentrically carried by detent stud 110 . One radially extending leg of spring 112 is fixedly retained by an engagement feature 113 integrally formed in a wall portion of lower housing portion 60 . A second radially extending leg of spring 112 continuously bears against a detent stud pin 114 carried with detent lever 108 . Thus arranged, torsion spring 112 continuously urges detent lever 108 in a clock-wise direction and into contact with striker plate 70 . Rotational travel of detent lever 108 is limited by rubber detent stop bumper 116 fixedly carried by a retention feature 118 integrally formed in lower housing portion 60 .
A drive mechanism 120 is disposed concentrically upon drive axle or shaft 92 . A striker plate cam 122 is carried on shaft 92 through an intermediate bushing 124 . Thus, cam 122 is carried by, but is free to rotate about shaft 92 . A detent lever cam 126 and a switch cam 128 are stacked upon striker plate cam for rotation therewith. Striker plate cam 122 is aligned for rolling engagement with roller bearing 96 to effect positioning of the striker plate 70 (and striker member 38 ) as a function of the angular position of striker plate cam 122 . Likewise, detent lever cam 126 is aligned for sliding engagement with a follower 130 integrally formed on the free end of detent stud pin 114 for selectively rotating detent lever 108 into and out of engagement with the adjacent end surface of striker plate 70 as a function of the angular position of detent lever cam 126 . Furthermore, switch cam 128 is aligned for sliding engagement with a contact switch 132 , which has a plurality of electrical terminals 133 which are electrically in circuit with control circuit 52 to selectively enable or disable the control signal as a function of the angular position of switch cam 128 . Control switch 132 is appropriately mounted by internal features (not illustrated) preferably integrally formed within upper housing portion 58 of housing assembly 36 .
A phasing carrier 134 is concentrically disposed on switch cam 128 and serves to key the three cams 122 , 126 and 128 for rotation in unison about shaft 92 . Carrier 134 defines four circumferentially arranged axle receiving bores 136 . A ring or spur gear 138 is concentrically disposed above carrier 134 and is grounded by an integral extension 140 , which is fixedly attached to the upper free end of detent stud 110 . Each of four planetary gears 142 are carried for rotation about a separate axle 144 extending upwardly from a respective axle receiving bore 136 . A sun gear 146 is carried for rotation on shaft 92 and is positioned concentrically with ring gear 138 and the intermediate circumferential array of planetary gears 142 to effect a gear reduction there between as is well known. Sun gear 146 includes an integral flange 148 for affixation with a large helical gear 150 . Shaft 92 extends through helical gear 150 and terminates in a support bushing feature 152 integrally formed in upper housing portion 58 . Likewise, detent stud 110 extends above torsion spring 112 and terminates in a support bushing feature 153 integrally formed in upper housing portion 58 .
A permanent magnet D.C. motor 154 controlled for uni-directional operation is affixed to upper housing portion 58 via a motor retainer bracket 156 . Control lines 56 ( FIG. 1 ) are extended to electrical terminals 157 of motor 154 , placing it in circuit with control circuit 52 . The armature shaft 158 of motor 154 carries a worm gear 160 for rotation therewith. The cantilevered free end of armature shaft 158 is supported axially and radially by a motor worm bearing 162 and a thrust plate 164 , which are secured in assembly with upper housing portion 58 by integral or discrete features (not illustrated).
Referring to FIG. 4 , the juxtaposition of specific internal components of striker assembly 10 is illustrated. Specifically, the arrangement of the portion of the power transmission, including the ring gear 138 , the planetary gears 142 and the sun gear 146 can be clearly seen. The depicted preferred design provides reduced gear speed which, with optimized material selection provides quality sound during the cinching operation. It is to be understood that the gear ratios, as well as component dimensions, materials, surface finishes and the like will vary, depending upon the specific application contemplated, as should be apparent to one of ordinary skill in the art.
Switch cam 128 has an outer peripheral surface 166 defining a single lobe 168 extending circumferentially approximately 270 degrees. Cam surface 166 is in sliding contact with a spring-loaded plunger 170 of contact switch 132 , which changes conductive state of switch 132 as a function of the angular position of the cam lobe 168 . The configuration and phasing of the cam lobe 168 can be varied depending upon the intended application.
Referring to FIGS. 1 through 4 , bearing 86 defines an axial through passage 172 which is threaded to receive a bolt or other suitable fastener (not illustrated) extending through wall 30 of vehicle opening 18 and through passage 89 of cover plate 62 to effect attachment of striker assembly 10 to the host motor vehicle 12 at a location adjacent closure member 16 . Similarly, a threaded blind bore (not illustrated) is formed in bearing 90 of drive axle 92 to receive a second bolt or suitable fastener extending through wall 30 of vehicle opening 18 and through passage 95 of cover plate 62 . This arrangement is very robust, and directs impact forces from the striker member 38 through the striker plate 70 and bearings 86 and 90 , directly to the body 14 of the motor vehicle 12 and avoids high force loading of the transmission components.
Referring to FIGS. 5 and 6 , the range of movement of the striker plate 70 and detent lever 108 under various operating conditions of the striker assembly 10 are illustrated. FIG. 5 depicts the striker plate 70 in its first end limit of travel, corresponding with the system being in the pre-latch or presented position. FIG. 6 depicts the striker plate 70 in its second end limit of travel, corresponding with the system being in the closed or cinched position.
Striker plate 70 and detent lever 108 define facing, cooperating edge surfaces 174 and 176 , respectively, which provide a detent function when the striker plate 70 is in its first limit of travel ( FIG. 5 ) and an interlock function when the striker plate 70 is in its second limit of travel ( FIG. 6 ). Edge surface 174 of striker plate 70 includes two leftwardly extending protuberances 178 and 180 defining opposed abutment faces 182 and 184 , respectively. Edge surface 176 of detent lever 108 includes two rightwardly extending protuberances 186 and 188 defining facing abutment surfaces 190 and 192 , respectively.
FIG. 5 depicts striker assembly 10 with a detent, comprising abutment surfaces 182 and 190 , engaged to retain striker plate 70 in the illustrated presented position. Prior to engagement of the latch 26 with the striker member 38 , the detent and compression spring 102 serve to hold the striker plate 70 in its illustrated position.
During normal operation, engagement of the latch 26 and striker member 38 will result in a control signal energizing the D.C. motor 154 , which will drivingly rotate the striker plate cam 122 , detent lever cam 126 and switch cam 128 in a clockwise direction as viewed in FIGS. 4 and 5 . The striker plate cam 122 and detent lever cam 126 are phased whereby a first lobe 194 of detent lever cam 126 will initially rotationally displace the detent lever 108 (via its sliding engagement with follower 130 , which is illustrated in phantom for the sake of clarity) counterclockwise away from the striker plate 70 , providing rotational clearance there between. Thereafter, the lobe 196 of the striker plate cam 122 will act upon the roller bearing 96 to displace the striker plate 70 from its presented position ( FIG. 5 ) to its cinched position ( FIG. 6 ). As the three cams continue to rotate, the detent lever cam 126 (in phantom) will release the detent lever 108 , which, under the influence of torsion spring 112 will return to the position depicted in FIG. 6 , wherein abutment surfaces 184 and 192 are facing one another in the interlocked position.
For the purposes of this patent, a “detent” is a mechanical engagement which restrains the striker plate 70 in its position in FIG. 5 and which can be released with or without the presence of the control signal by the application of a predetermined impact load (caused by manual slamming shut of the closure member 16 ). An “interlock” is a positive mechanical engagement, which restrains the striker plate 70 in its position in FIG. 6 and which can only be released in the presence of the control signal which effects displacement of the detent lever 108 via rotary action of detent lever cam 126 .
Abutment surfaces 182 and 184 of protuberances 178 and 180 , respectively, are generally parallel to the line of elongation of the striker plate 70 . As illustrated in both FIGS. 5 and 6 , abutment surface 190 of protuberance 186 is angularly offset from the line of elongation of striker plate 70 , while abutment surface 192 of protuberance 188 is generally parallel to the line of elongation of striker plate 70 . Accordingly, when in the detent position of FIG. 5 , abutment surfaces 182 and 190 are in line contact and are slightly diverging. Thus, a high impact force loading will result in protuberance 178 forcing detent lever protuberance 186 leftwardly, permitting displacement of the striker plate 70 and effecting manual cinching of the striker assembly 10 . Alternately, when in the interlocked position of FIG. 6 , abutment surfaces 184 and 192 are in surface contact and will apply purely compressive loading there between until failure.
When the striker assembly 10 is in the interlocked condition depicted in FIG. 6 , and the operator releases the latch 26 from engagement with the striker member 38 , either electrically or mechanically, this change of status will be sensed by control circuit 52 , which, in turn, will energize motor 154 . Motor 154 will drive the three cams clockwise from the positions depicted in FIG. 6 . Initially, a second lobe 195 of detent lever cam 126 will displace detent lever 108 counterclockwise away from striker plate 70 , thereby releasing the interlock condition. Thereafter, the striker plate cam 122 will continue to rotate as its lobe 196 rotates away from roller bearing 96 , returning the striker plate 70 to the presented position depicted in FIG. 5 .
Referring to FIGS. 7 and 8 , the loss of power “over-ride” feature is illustrated. FIG. 7 depicts the initial displacement of the striker plate 70 as a result of normal manual operation of the door or closure member 16 without the presence of electrical power. The preferred design of the power striker assembly 10 can withstand a 75 J slam without damage to the mechanism. As the striker plate 70 moves from the presented position, the roller bearing 96 separates from contact with the striker plate cam 122 , and the edge of abutment surface 182 of striker plate 70 “wipes” along the angled abutment surface 190 of detent lever 108 . As striker plate 70 continues to rotate, striker plate protuberance 178 passes beyond protuberance 186 of detent lever 108 , which is then resiliently biased back towards the position depicted in FIGS. 5 and 6 by torsion spring 112 . Finally, as best viewed in FIG. 8 , as the striker plate 70 approaches its cinched position, abutment face 184 of protuberance 180 of striker plate 70 passes beyond abutment surface 192 of protuberance 188 of detent lever 108 , torsion spring 112 urges the detent lever protuberance 188 inwardly behind striker plate protuberance 180 , thereby interlocking the striker plate 70 in its cinched position as depicted in FIG. 8 .
As described herein above in relation to FIG. 2 , slot 74 in striker plate 70 is elongated generally along its line of elongation. Slot 76 is crescent shaped and elongated in a direction substantially offset from the line of elongation of slot 74 . Finally, the first or striker leg 42 of the striker member 38 is positioned intermediate slots 74 and 76 and, in the illustrated preferred embodiment, is slightly radially offset there from.
The applicants have discovered that the end of the striker plate 70 associated with slot 74 is subjected primarily to translational movement along the line of elongation as the striker plate 70 transitions between its end limits of travel, and that the end of the striker plate 70 associated with the second slot 76 is subjected primarily to rotational movement as the striker plate 70 transitions between its end limits of travel. This hybrid motion in the two dimensional plane defined by bottom wall 72 of lower housing portion 60 subjects the striker plate 70 to simultaneous translation and rotation. Furthermore, the applicants have determined that the judicious selection of a specific point on the surface of the striker plate 70 will result in linear displacement of that point as the striker plate traverses its end limits of travel. The striker leg 42 is mounted concentrically at that point.
In practice, the identification of the optimal mounting location of the striker leg 42 can be established by mathematical modeling or by empirical development and can be accomplished by one of ordinary skill in the art in view of the forgoing teaching without undue experimentation.
It is contemplated that a striker boot (not illustrated) can be provided to close elongated opening 66 of wall 30 from intrusion of water, contaminants and the environment matter while enhancing the overall appearance of the design of the preferred embodiment of the invention.
Referring to FIGS. 9 through 11 , an illustrative model of a drive mechanism 200 of a power cinching striker assembly sans housing is illustrated. The drive mechanism 200 includes a D.C. motor 202 driving a gear reduction stage 204 , which, in turn, drives a striker plate cam 206 and a phased switch cam 207 . Striker plate cam 206 is in rolling contact with a cam follower 208 carried by a striker plate 210 , which, in turn, carries a striker member 212 . Phased switch cam 207 is in rolling contact with a contact switch 211 . A compression spring 214 continuously urges the striker plate 210 toward its presented position as illustrated in hard line in FIG. 11 .
Except as otherwise indicated, the embodiment and application of the invention depicted in FIGS. 9 through 11 operates in all material respects as described herein above with regards to the embodiment of FIGS. 1 through 8 .
Referring to FIG. 11 , the striker plate 210 is horizontally elongated, defining a first slot 216 which is elongated generally parallel with the line of elongation of the striker plate 210 and a second generally crescent shaped slot 218 which is elongated along an axis which is offset from the axis of elongation of the striker plate 210 . Bushings 220 and 222 extend through slots 216 and 218 , which are adapted for affixation to a housing assembly (not illustrated).
Striker member 212 comprises a first or striker leg 224 and a second or support leg 226 interconnected at the free ends thereof by a bridge member 228 . Striker leg is concentrically disposed on the precise location of striker plate 210 determined to move linearly as striker plate 210 translates between ins end limits of travel. In FIG. 11 , striker plate 210 is depicted in hard line in its pre latch or presented position and is depicted in phantom in its closed or cinched position. The axis of striker leg 224 in the presented position is designated as the intersection of the line of travel designated X and the crossing line designated EOT 1 (end of travel 1 ). The axis of striker leg 224 in the cinched position is designated as the intersection of the line of travel X and the crossing line designated EOT 2 (end of travel 2 ). Thus configured, as the striker plate 210 simultaneously translates and rotates between its end limits of travel, the centerline of the striker leg 224 moves linearly along line X, providing the cost, packaging and performance advantages described herein above.
It is to be understood that the invention has been described with reference to specific embodiments and variations to provide the features and advantages previously described and that the embodiments are susceptible of modification as will be apparent to those skilled in the art.
Furthermore, it is contemplated that many alternative, common inexpensive materials can be employed to construct the basic constituent components. Accordingly, the forgoing is not to be construed in a limiting sense.
The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used is intended to be in the nature of words of description rather than of limitation.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings. For example, the striker leg can be repositioned on the locus of points of potential linear travel on the striker plate to increase or decrease its length of linear travel without retooling the various striker assembly components. It is, therefore, to be understood that within the scope of the appended claims, wherein reference numerals are merely for illustrative purposes and convenience and are not in any way limiting, the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents, may be practiced otherwise than is specifically described. | A power striker assembly effects final positioning of a vehicle closure member and includes a fixed frame and a striker member carried on a striker plate for selective engagement of a latch carried on the closure member, to displace the closure member from a presented position to a cinched position. Guide means interconnects the frame and striker plate to effect simultaneous translational and rotational displacement of the striker plate between end limits of travel to produce linear displacement of the striker member. An actuator selectively displaces the striker plate between its end limits of travel in response to a control signal. Finally, an interlock fixes the striker plate in the cinched position in the absence of the control signal. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to U.S. Provisional Application No. 61/973,297 filed Apr. 1, 2014, the contents of which are incorporated entire herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a method, system, or computer application that allows to define a product configuration and using this configuration, manage entirely user experience related to this product, and in particular a method in where a rules engine containing directives, logic and constraints controls without the need of human intervention; the content, form and behavior of the user interface on a computational device. All elements and logic contained in the interface can be controlled directly by individual or multiple sets of rules in the rules engine. Rules can be added, edited and operated on by human or machine agents. Any change in the state of the rules is propagated to the user interface automatically and in real time.
BACKGROUND OF THE ART
[0003] There are several state of the art applications which provide solutions to a) create a visual representation of a configurable product; b) generate a user interface UI based on user selected criteria or pre-determined criteria. Until now no solution has attempted to combine these characteristics and extend them to:
[0004] a) dynamically generate and control the entire user interface and it's content and behaviors based on rules evaluation;
[0005] b) update the rules and/or user experience in real time using human and/or machine agents and streams of big data being generated every nanosecond by the internet of things.
[0006] c) or a combination of both of the above. (a+b).
[0007] With current technologies when subject matter experts make changes to rules, they then need to communicate with the IT specialists (e.g. UX/UI designers, front end programmers) and request modifications to the user interface to support their changes.
[0008] In the case of various personalization systems including CMS (content management systems) and banner ad serving systems, changes to only an element of the UX is made according to pre-determined criteria.
OBJECT OF THE INVENTION
[0009] In order to provide a solution to the limitations of the systems of the prior art, the present invention provides a method that allows to configure digital experiences using several sources of information such as intelligent agents, remote services, etc., by means of a direct link between a dynamic rules engine and the total user interface, where the former controls the latter in real time.
[0010] Some of the advantages of the invention are the following:
[0011] Reducing the time to market of new products and services;
[0012] Simplify the process of updating product, process and personalized UI data;
[0013] Enabling more complex decision criteria to guide the user and information experience;
[0014] Embed decision criteria with data from analytics or AI engines that are updating the rules engine in real time;
[0015] Drive UX (user experience) behavior, content and form in real time; and
[0016] Enhance and extend the capabilities of existing software development UI (user interface) tools such as HTML5, CSS3, j-Query or other JS frameworks.
[0017] Enable the UX/UI to reflect the dynamic changes in the tsunami of big data being generated every nano second by the internet of things that the UI is supposed to represent.
SUMMARY OF THE INVENTION
[0018] The present provides a method that allows to configure digital experiences using several sources of information as intelligent agents, remote services, etc. In particular, the invention is a method, system or computer application where a rules engine containing directives, logic and constraints controls without the need of human intervention; the content, form and behavior of the user interface (in other words controlling the entire user experience on said interface) on a computational device. All elements and logic contained in the interface can be controlled directly by individual or multiple sets of rules in the rules engine. Rules can be added, edited and operated on by human or machine agents. Any change in the state of the rules is propagated to the user interface automatically and in real time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 shows a general diagram of the operational link between the components of the method object of the present invention;
[0020] FIG. 2 shows a data model for the database implementation according to the present invention; and
[0021] FIG. 3 shows a flowchart of the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] According to the present invention, the Digital Experience Configurator is a process, method, and software that allows a user to model entities and establish rules that govern their behavior. The following tables summarize general characteristics of the method's components.
[0000]
TABLE I
RulesNet
Evaluates the logic and provides product, process, user and
options information. This is implemented by means of a
software application executed in a computer, that has means
of communication with the method's other components.
This is modeled as shown in Table II.
RulesNet
Where the rules information persists and is updated by the
Database
rules engine. This is implemented by any existing database
application.
RulesNet
Allows human users and machine to machine interfaces to
admin. UI
create, perform operations on and maintain the rules
engine. Can be implemented with a computer application
that provides access via a browser or via an application
programming interface.
Touchpoint
Process that a) translates the directives from the rules
Generator
engine into a message that is understood by the Touchpoint
Engine application which is building the user interface and
b) directs user input back to the rules engine. Can be
implemented as a software application for each type of
device or browser (Pc, Mac, Chrome, iOS, Android, etc).
Touchpoint
Interprets the rules from within the client side browser or
Engine
device to generate the UI/UX. Can be implemented as part
of the touchpoint generator or as in independent software
application.
[0000]
TABLE II
Logical Model of RulesNet Entities and Behaviour
Categories of Objects. (e.g. clothing)
Objects (e.g. shirts)
Components: Part of an entity that has clear purpose
(e.g neck, fabric)
Domains: characteristics and their values that form a
component. (e.g: fabric type (jersey, silk, cotton),
fabric color (blue, white, green))
Constraints can be:
Intra-object: within an object. (e.g fabric.type = silk and
fabric.color are combinations)
Inter-object: between objects. (e.g fabric.type = silk and
neck.type = v_neck are combinations with different
components)
Availability actions can be of:
Acceptance. (e.g. if fabric.type = silk and fabric.color = red
combination is a valid option)
Rejection. (e.g. if fabric.type = silk and fabric.color = red
combination is not valid)
Acceptance depending on further evaluation.
Rejection depending on further evaluation.
Rules can be:
Inter Domain Restriction. (e.g. on fabric.type = silk remove
fabric.color => [red, blue])
Inter Domain Default Object. (e.g. on neck.color = white then
set fabric.type = cotton)
Inter Domain Non-Valued Restriction. (e.g. on neck.color
change execute predicate(myPredicate) on fabric.color)
where myPredicate. expression =
javascript.evalAndApply(‘fabric.color =
external.agent.getTrendyColorByBaseAndCustomer(neck.color,
customerEmail))’)
Metadata:
Each element within the system can be associated with metadata that
will be used to further model the user experience or complete the
involved transaction or exchange.
[0023] FIGS. 1 and 2 illustrate the methods covered by this invention as explained in the following detail.
[0024] The interaction flow is configured via two distinct operations:
a. Entity Configuration: consists in defining the entity as an association of components, domains, values, rules and availabilities. b. Digital Experience Configuration: the way the product will be presented to the user. Configuration options, input restrictions and all aspects of user interaction.
A. Product Configuration
[0027] To create and configure an entity, the user follows this sequence of operations. These operations are contained within the component RulesNet Admin UI, as mentioned in Table I. (e.g. This is to be implemented as a software application providing access from a console for a human to input the required data or providing access via an application programming interface API) to an external machine agent.)
1) Create an Entity 2) Assign a entity Name and entity Description 3) Create Domains, which are one way attributes of the component(s). These domains may be shared by more than one components. A domain represents all available values to this attribute. A domain maybe qualitative or quantitative. In the first, qualitative descriptors are used to represent the domain, in the second continuous values are presented as discreet ranges and are used to represent the domain. This facilitates the dynamic domain interactions.
If user selects a qualitative domain value it must enter a value name, canonical name and the value that represents the current quality. If user selects a quantitative value, the method allows to define this continue value as it as a ranged value. The user must enter value name, ranks, step and type (decimal/natural) of quantitative value.
4) Create component. A component is associated to an entity by entering the component name. A component is atomic, real and measurable. e.g. wheels of a bike. 5) Associate the domain(s): Domain and domain values must be added to this association. Users may add a domain value element constraint that are not allowed on certain component/domain association. This is the case of component/domain/value contradictions as quantitative values (as ranges) that may collision between themselves and produce a non atomic domain value. 6) The last step of this process is to associate the component with the desired product/services. This is done by creating a link between both.
B. Digital Experience Configuration
[0036] This stage of the method is to define the dynamic entity view. The dynamic view is the aspect of this method that allows to model the behavior of the universal entity definition. The model is created by following a 2 step process:
1. Constrain the universe of possible entity configurations 2. Create and add rules to control entity behavior 3. [optional] Create and add business custom metadata.
Creating the Universe of Possible Entity Configurations
[0040] An availability is a valid combination of component/domains/values. They are grouped/organized in clusters within an entity. To create one, users have to add it to entity availability snapshots.
[0041] Entities can have multiple availability snapshots according that respond to different business rules/constraints. e.g. entity behaviors may change on a given date or given conditions.
[0042] Availabilities are created by defining the following:
1) Availability scope (component/intercomponent), 2) Associated component(s) (one for scope component, many to intercomponent) 3) Default action 4) Evaluation priority
[0047] Next, user must add availability items selecting a combination of domain/values 3 and the behavior that touchpoints engine should follow when this combination is selected. The allowed behaviors for availabilities or availability items are:
Reject: Selected combination must be rejected Accept: Selected combination must be accepted Reject if cant eval next: Combination should be rejected in case of not exist other availability that fits in this combination. (this may happen on inter component availability definitions that may collision with another availability definitions. so, the method forces to indicate the evaluation priority and the first combination found may block (or not) the evaluation of the next element (if it exists)
[0051] Accept if cant eval next: sames as previous, but the combination is accepted
Create and Add Rules to Control Entity Behavior
[0052] A rule is an extension of an availability, that allows to create another kind of behaviors as default value set according to selected values or applying constraints and predicates. Rules also be associated to a entity availability snapshot.
[0053] This method allows organizing entity rules into a tree structure.
[0054] To create a rule users must enter:
1) name. 2) acceptance (addition or subtraction). 3) priority. 4) type. (defines the UI behavior)
Type 1=Inter domain default object (IDDO): Represents default value that a domain (A) is going to take in case of other domain (B) change. where A!=B.) Type 2=Inter domain restriction (IDR): Constrains (according to rule acceptance) values between domain(s). where a selection change on domain (A) using values (VA1, VA2 . . . VAx) must add (or sub) in domain (B) the following values (VB1, VB2 . . . VBy). where A!=B. Type 3=Inter domain non valued restriction (IDNVR): similar to IDR but a when a domain change occurs a predicate is applied on the domain (B) values.
5) Select the component/domain/[values] that rule is applied to. 6) Select a predicate (see following explanation)
Predicates
[0064] Predicates are expressions that can be executed on domains. These expressions are described in proto-languages as javascript and is a mechanism to define business rules and access external sources of information.
[0065] Per method specification, the predicate expressions must be executed on the touchpoints engine. If the destination platform does not support javascript-like expressions, touchpoints engine is going to use predicate names to execute those behaviors.
Create and Add Business Custom Metadata
[0066] The method also allows to define variable data (structure free) associated to specific business logic. This information can be attached to any data structure shown on FIG. 2 . An external agent (human or machine) can update associated metadata (e.g. inventory on hand) within the availability item structure. This change may trigger execution (according to rules and predicates) business behaviors on the UI. (e.g if inventory on hand is zero, switch availability item from accept to reject; the item it will not be longer available to be selected on configuration)
[0067] 3 The current definition of component/domain/value definition is a NP-Complete problem. The order or complexity of the solution is about
[0000] ( O )=( O ̂( Cr*Dr*Vr )). wherein:
[0068] Cr is the component vector range,
[0069] Dr is the associated range of domain vector and
[0070] Vr is the associated range of domain value vector.
[0071] An availability uses an accept or a reject criteria, therefore the equation can be written as (O)=(Ô(Cr*Dr*Vr))/2 where the division by two is related to amount of information (theory of information) when rejects or accepts the availability. So the worst case occurs when the size of availability vector (using acceptance) is equals to the reflected (or negative) availability vector (using rejection). Av(ex,accept)˜Ac(ex,reject).
Generating the Digital Experience
[0072] The method workflow shown on FIG. 3 explains how method components interacts between themselves to generate a UI/UX that can be controlled using declared static and dynamic views.
[0073] The diagram from FIG. 3 is a UML sequence artifact. is using trails to define sections and scopes. the sections are identified as: AdminUI, Rules Database, Rules Engine, Touchpoint Generador, Touchpoint Engine and Endpoint
[0074] Initially the workflow needs a previous definition of entities inside administration UI 1 . 1 (primarily data structures as domains/values, components, entities availability, entities rules). The business rules are stored in rulesnet database 1 . 2 . This database is a abstract storage implementation where its possible to implements different database engines (as RDBMS (sql) or Document based (no-sql)) without expensive business change.
[0075] When an endpoint requests a new configuration 2 . 1 , the engine takes cares of authorization and authentication in the remote services where rules engine is running 2 . 2 and gets all entity data from a single publication (static and dynamic views with (or not) embedded metadata) 2 . 3 then the engine evaluates/executes all rules that may update the dynamic view output 2 . 4 . the output 2 . 5 of rulesnet (static and dynamic view) is used to generate a correct UX/UI associated to broker platform (web/mobile/etc).
[0076] The UI its rendered in endpoint platform 2 . 7 . the user may see/use the generated UI at the end of a transaction 2 . 8 it represents that the user has selected a valid entity configuration (according to static/dynamic view). after that the rule engine will validate the selected configuration 2 . 9 . with a valid configuration the broker can continue with its use case.
[0077] The mechanisms that control the endpoint platform 2 . 7 have been extensively explained in FIG. 1 and FIG. 2 . | The present invention relates to a method, system, or computer application that allows to define a product configuration and using this configuration, manage entirely user experience related to this product, and in particular a method in where a rules engine containing directives, logic and constraints controls without the need of human intervention; the content, form and behavior of the user interface on a computational device. All elements and logic contained in the interface can be controlled directly by individual or multiple sets of rules in the rules engine. Rules can be added, edited and operated on by human or machine agents. Any change in the state of the rules is propagated to the user interface automatically and in real time. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to railroad track components for turnouts, crossings and the like.
2. Description of Prior Art
U.S. Pat. No. 5,765,785 of which Applicant is inventor, provided certain improvements in railroad track crossings. Among these were a new and improved railroad track crossing which included an interchangeable insert. Among the components of the structure were support fillers and filler blocks. These two structural components had vertical contact surfaces on side portions which were adapted to mate with and fit against corresponding flat vertical surfaces formed on the upright web portion of the rail. The support fillers and filler blocks also had downwardly sloping upper and lower surfaces. These sloping surfaces were intended to conform or correspond to the conventional sloped planar surfaces present in rails or other track pieces. These sloped planar surfaces were present in rails below the wheel contact portion of the rail and also on the base portion of the rail.
However, problems have been found to exist. Due to the rolling process of forming rails, these were minor variations in the angles and ratios of these portions of the rail. The dimensions and slope of the vertical flat on the web, and the sloped surfaces below the wheel contact portion and on the base portion and their relative spacing, had minor variations in different rail members and also along the length of any one particular rail member.
It was thus difficult to achieve a proper match between the rails, filler blocks and filler members when track structures such as frogs and crossings were assembled. To the extent that a properly fitted match between these three contact surfaces was not achieved, the relative strength of the assembled structure was reduced, and the service life of the structure decreased. This could in some cases after time pose a possible safety concern.
SUMMARY OF INVENTION
Briefly, the present invention provides new and improved structural components in the form of filler members and filler blocks for railroad track structures. The structures may be, for example, in the form of junctures between adjacent rails and may include frogs, guardrail and crossings.
The filler members according to the present invention are attached to a rail in the railroad track structure for support purposes. The filler members include a filler member body which has a laterally outwardly extending vertical contact surface which engages a corresponding flat vertical surface on a web portion of the rail. The filler members include a leg member extending downwardly from the filler member body. The leg member has a horizontal contact surface for mounting on a corresponding horizontal flat surface formed on a sloped surface of a base portion of the rail. The filler members also have an upwardly extending upright which has a horizontal planar upper contact surface to engage a corresponding horizontal flat surface formed below a head portion of the rail. The engagement of the horizontal and vertical surfaces on the filler member with corresponding surfaces on the rail provides ease of alignment and installation, as well as increased strength and better load transfer.
The filler blocks of the present invention are attached between adjacent rails in the railroad track structure. The filler blocks include a filler block body which has a laterally outwardly extending vertical contact surface formed on it to engage corresponding planar flat vertical surfaces formed on web portions of the adjacent rails. The filler block body has a horizontal lower contact surface on a lower surface for mounting on corresponding horizontal flat surfaces formed on base portions of the adjacent rails. The filler block bodies also have one or more uprights formed extending upwardly, having horizontal upper contact surfaces formed on them. The upper contact surfaces on the uprights engage corresponding horizontal flat surfaces below head portions of the adjacent rails. The engagement of the horizontal and vertical contact surfaces of the filler blocks with corresponding surfaces on the adjacent rails provides ease of alignment and installation, also increasing strength and improving lead transfer.
Railroad structures with filler members and filler blocks according to the present invention thus have increased strength and extended service life. These structures are also more easily aligned and installed, and are more easily maintained.
BRIEF DESCRIPTION OF THE DRAWINGS
The characteristic details of the present invention are clearly shown in the following description and accompany figures, which illustrate this and provide points of reference to indicate the same parts in the figures shown.
FIG. 1 is a cross-sectional view of a railroad juncture between adjacent rails with filler members and filler blocks according to the present invention.
FIG. 2 is a cross-sectional view of one of the rails of FIG. 1.
FIGS. 3 and 4 are cross-sectional views of the filler members of FIG. 1.
FIG. 5 is a cross-sectional view of the filler block of FIG. 1.
DESCRIPTION OF PREFERRED EMBODIMENT
In the drawings, the letter S designates generally a railroad track structure formed between a pair of adjacent track components, such as rails R. The structure S also includes a pair of filler members M and a filler block body B. The railroad structure S may be a frog, turnout or crossing, as disclosed in U.S. Pat. Nos. 5,765,785; 5,393,019 and 5,303,884, each of which is incorporated herein by reference.
Turning first to the rails R, each of such rails has a flat vertical surface 10 formed on each side of a web portion 12 between a base portion 14 and a head portion 16. The flat vertical surfaces on the rail web 12 are formed in the manner disclosed in Applicant's U.S. Pat. No. 5,765,785, which is incorporated herein by reference. The vertical flat surfaces 10 serve as precise measurement and alignment references for other surfaces formed on the rails R and other components of the structure S, as will be set forth below.
Each of the rails R also includes a horizontal flat surface 18 formed on an intermediate area 20 of each outwardly sloped upper surface 22 of the base portion 14. The flat surfaces 18 are formed in the intermediate areas 20 between a lower radius area 21 of the web portion 12 and a lower side portion 24 of the base portion 14. The flat surfaces 18 are formed in a common horizontal plane which is perpendicular within the accuracy of precision machining tolerances to the vertical plane in which the flat vertical surface 10 of the web portion 12 is formed. Each of the rails R also includes a horizontal flat surface 26 formed on each lower inwardly curving surface or radius 28 beneath the head portion 16. The flat surfaces 26 are formed extending inwardly from a side edge portion 30 at its juncture with the inwardly curving surface 28 below the head portion 16. The flat surfaces 26 of the head portion 16 are formed in a common horizontal plane as shown. The horizontal plane of flat surface 26 is perpendicular within the accuracy of machining tolerances to the vertical plane in which the flat surface 10 of the web portion 12 is formed. The horizontal plane of flat surfaces 26 is thus parallel within the accuracy of machining tolerances to the horizontal plane of the flat surface 18 in the base portion 14.
The filler member M is formed of a suitable strength alloy steel, depending upon the intended load and service usages of the rail structure S. The filler member M has a central filler member body portion 32 of generally rectangular vertical cross-section. The filler member body 32 further has a lateral width equal to the space between the vertical flat surface 10 and side portion 24 of base 14 and side portion 30 of head 16 of the rail R. The filler member body 32 has a laterally outwardly extending vertical contact surface 34 formed thereon for fitting engagement along its vertical extent with the flat surface 10 on the web portion 12 of the rail R.
Two filler members M are typically used in each rail structure S. They are normally of like construction, with their relative position in their longitudinal extent along the rails R reversed. The contact surfaces 34 of each filler member M thus face inwardly, as shown in FIGS. 3 and 4, to engage corresponding outwardly facing vertical surfaces 10 of rails R (FIG. 1).
The filler member M also includes a leg member 36 integrally formed with and extending downwardly from the filler member body 32 outwardly from the surface 34. The leg member 36 has a lateral horizontal contact surface 38 formed on it which is perpendicular to the vertical contact surface 34, again within the limits of machine tolerance accuracies. The spacing of the horizontal surface 38 from the vertical surface 34 on the filler member M conforms to the spacing of the surfaces 18 and 10, respectively, on the rail R. In this way, when the vertical surfaces 34 and 10 are in proper engagement, the horizontal surfaces 38 and 18 are also fittedly engaged and aligned in proper engagement.
The filler member M includes an upright 40 integrally formed with and extending upwardly from the body member 32 in alignment with the leg member 36. The upright 40 has a lateral horizontal contact surface 42 formed in it which is perpendicular to the vertical contact surface 34 and parallel to the horizontal surface 38. The spacing of contact surface 42 from vertical surface 34 and horizontal surface 38 on the filler member M conforms to the spacing of horizontal surface 26 from the surfaces 10 and 18 on the rail R. Accordingly, when the vertical surfaces 34 and 10 are fitted against each other, horizontal surfaces 42 and 38 on the filler member M are in engagement and proper contact along their lateral surface extent with the surfaces 26 and 18, respectively, of the rail R.
The length of the filler member M and its extent along the rail structure R with which it is mounted is determined by the nature of the rail structure with which it is to be used and load bearing considerations. A suitable number of connector passage holes are formed in the manner described in U.S. Pat. No. 5,765,785 along the length of the rail R and the filler member M laterally extending therethrough. The connector passages allow bolts and other suitable connecting mechanisms to be inserted to connect these components of the rail structure S with each other.
The filler block body B is formed of a suitable strength alloy steel depending upon intended load and service usage. The filler block B includes a central filler block body 50 of generally rectangular vertical cross-section, having a lateral width substantially equal to the intended spacing between adjacent rails R. More particularly, the filler block body 50 has laterally outwardly extending vertical contact surfaces 52 formed thereon for engagement with corresponding planar flat vertical surfaces 10 on the web portions 12 of the adjacent rails R.
The filler block body 50 also includes a horizontal lower contact surface 54 extending laterally beneath the central portion of the filler block body 50. The lower contact surface 54 is adapted for mounting on and in engagement with horizontal flat surfaces 18 on facing portions of adjacent rails R in the structure S. The horizontal contact surface 54 is perpendicular to the vertical contact surface 52 of the filler block body 50 within the limits of machining tolerance accuracy. The spacing of the vertical surfaces 52 of the filler block body 50 from the horizontal contact surface 54 conforms to the spacing of the inwardly facing surfaces 18 and 10 formed on the adjacent rails R in the structure S. When the vertical surfaces 52 on the filler block body 50 are brought into contact with the vertical flat surfaces 10 of the adjacent rails R, and are in proper engagement, the horizontal flat surface 54 of the filler block B is fittingly engaged with the horizontal contact surfaces 18 of the adjacent rails R. The components of the rail structure S are thus in proper, load bearing and load transfer fitting engagement.
The filler block B also includes a pair of vertically extending uprights 56 formed on the filler block body 50. The uprights 56 are formed at spaced positions on an upper surface 58 of the filler block body 50 corresponding to the required spacing between the inwardly facing horizontal contact surfaces 26 of adjacent rails R in the structure S. Each of the uprights 56 has a horizontal upright contact surface 60 formed thereon for engaging a corresponding one of the horizontal flat surfaces 26 of the adjacent rails R in the structure S.
The spacing of the horizontal contact surfaces 60 from the vertical surfaces 52 on the filler block 50 corresponds to the spacing of the surfaces 26 and 10 in the rails R. When the vertical surfaces 52 are fitted against the rail surfaces 10, the horizontal contact surfaces 60 are in load bearing engagement with the surfaces 26 beneath the head portion 16 of the rails R.
Again, the length of the filler block body 50 is determined by the nature of the rail structure S with which the filler block B is to be used. Also, a suitable number of laterally extending connector openings are formed in and along the length of the filler block B. The openings so formed are for alignment with and connection to bolts or other suitable connecting mechanisms inserted through corresponding connector passages or openings in the rails R and the filler member M. In this way, the structural components of the rail structure S are connected together. When so connected, the contact surfaces of the filler members M and filler block B, particularly the horizontal ones, are in firm, load transfer position with corresponding surfaces of the rails R. The amount and extent of this load bearing contact offsets any possible weakening of the rails R due to the formation of contact surfaces on them. Further, the flat surfaces 26 and 18 are not formed in the areas 28 and 21 of rails R of the radius between the head and base portions, respectively, and the web 12. Thus, machining the flat surfaces 26 and 18 in the rails R does not significantly reduce their strength.
Both the filler members M and the filler block B can be made from less expensive conventional steel than the rails R, since they are spaced from contact with railroad wheels, and thus are not subject to repeated impact and high wear.
The present invention thus allows the easy and precise manufacture of bars and fillers. Further, these pieces have a service life limited only by the steel life, since is quite difficult for these parts to become broken or worn during use. This means savings in time, money, and security in operation for the frogs, crossings, and guard rails.
The improved design of the present invention also provides a reference point which is the base for accuracy in assembly and manufacture of every part of a track component such as frogs, crossing or guard rails, at the same time strengthening the head rail resistance due to impact and loads to the matching planar surfaces in three separate locations between the rail R and the fillers.
Having described the invention above, various modifications of the techniques, procedures, material and equipment will be apparent to those in the art. It is intended that all such variations within the scope and spirit of the appended be embraced thereby. | The strength and reliability of railroad track structures, such as frogs, crossings, and guardrails, is enhanced. Filler members and filler blocks are fitted in to support and strengthen the structures. The filler members and filler blocks provide better matching and alignment of load transfer surfaces. The track structures with the improved components are more easy to align and assemble. The strength of the assembled track and structures is also increased, and the structures are more easily maintained. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part application of U.S. application Ser. No. 11/208,494 filed on Aug. 22, 2005, which is incorporated by reference herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention relates to the field of securing items and more specifically to a magnetic spring clip and system for securing items to clothing.
[0005] 2. Background of the Invention
[0006] Items such as writing instruments and flashlights have been secured to clothing by clips. For instance, a conventional writing instrument with a clip includes the writing instrument being retractable into an opening of a barrel and having an operating means including an activation button and an operating cam. Drawbacks to conventional clips used with writing instruments include the writing instrument being operated by a single operating means with the clip only functioning when the writing cartridge is retracted.
[0007] Consequently, there is a need for an improved clip and system for securing items such as writing instruments and flashlights to clothing.
BRIEF SUMMARY OF SOME OF THE PREFERRED EMBODIMENTS
[0008] These and other needs in the art are addressed in one embodiment by a magnetic spring clip. In an embodiment, a magnetic spring clip includes a clip base having a semi-circle shape with an opening for engaging an instrument. The magnetic spring clip also includes a pivot point within the clip base. In addition, the magnetic spring clip includes a shaft having a generally linear shape and upper and lower ends. The upper end of the shaft is attached to the clip base by the pivot point such that the shaft is moveable relative to the clip base. Moreover, the shaft further includes a magnetic lower end. The magnetic lower end is magnetically attracted to the instrument such that the lower end of the shaft contacts the instrument and secures any material between the lower end of the shaft and the instrument. The magnetic spring clip also has a clip magnet, wherein the clip magnet has a magnetic south pole and a magnetic north pole.
[0009] In addition, these and other needs in the art are addressed by a magnetic spring clip system. The magnetic spring clip system includes an instrument having a generally linear shape, wherein an internal magnet is disposed within the instrument. In addition, the magnetic spring clip system includes a magnetic spring clip that has a clip base having a semi-circle shape with an opening for engaging the instrument. The magnetic spring clip also has a pivot point within the clip base. In addition, the magnetic spring clip has a shaft having a generally linear shape and upper and lower ends, wherein the upper end of the shaft is attached to the clip base by the pivot point such that the shaft is moveable relative to the clip base. The clip further includes a clip magnet having a magnetic north pole and a magnetic south pole.
[0010] These and other needs in the art are further addressed by a magnetic spring clip system. The magnetic spring clip system has a pair of instruments having generally linear shapes, wherein an internal magnet is disposed in one of the instruments. In addition, the magnetic spring clip system includes a magnetic spring clip for attaching the pair of instruments. The magnetic spring clip includes a clip base having a semi-circle shape with an opening for engaging at least one instrument of the pair of instruments. The magnetic spring clip further includes a pivot point within the clip base. Moreover, the magnetic spring clip has a shaft having a generally linear shape and upper and lower ends, wherein the upper end of the shaft is attached to the clip base by the pivot point such that the shaft is moveable relative to the clip base. The shaft further includes a clip magnet. The internal magnet has a magnetic north pole and a magnetic south pole, and wherein the clip magnet has a clip magnet north pole and a clip magnet south pole.
[0011] The foregoing has outlined rather broadly 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 that form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent embodiments do not depart from the spirit and scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:
[0013] FIG. 1 illustrates a side view of a magnetic spring clip attached to a linear flash light instrument;
[0014] FIG. 2 illustrates an exploded view of the magnetic spring clip;
[0015] FIG. 3 illustrates the magnetic spring clip system with the magnetic spring clip in the closed position;
[0016] FIG. 4 illustrates the magnetic spring clip system with the magnetic spring clip in the open position;
[0017] FIG. 5 a illustrates a side view of the magnetic spring clip system;
[0018] FIG. 5 b illustrates a side cross-sectional view of the magnetic spring clip system;
[0019] FIG. 6 a illustrates a side view of the pivot mechanism of the magnetic spring clip;
[0020] FIG. 6 b illustrates a side cross-sectional view of the pivot mechanism of the magnetic spring clip;
[0021] FIG. 7 illustrates a side view of an embodiment of the magnetic spring clip system with an illuminated writing instrument;
[0022] FIG. 8 illustrates a side view of an alternate embodiment of the magnetic spring clip implemented with an illuminated writing instrument;
[0023] FIG. 9 illustrates a side view of an alternate embodiment of the magnetic spring system attached to a dual clip; and
[0024] FIG. 10 illustrates the south pole of a clip magnet proximate to a north pole of the magnet in an instrument.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] FIG. 1 illustrates magnetic spring clip 10 and magnetic spring clip system 100 for securing instruments to a person's clothing or other objects or devices. FIG. 1 shows an embodiment of magnetic spring clip 10 implemented on instrument 12 . As shown, magnetic spring clip 10 is attached to instrument 12 . The attachment of magnetic spring clip 10 to instrument 12 produces opening 14 between a portion of magnetic spring clip 10 and instrument 12 .
[0026] FIG. 2 shows an exploded view of magnetic spring clip system 100 . Magnetic spring clip 10 includes clip base 20 . Clip base 20 may have a semi-circle design such that an opening exists on one side. This opening enables clip base 20 to receive and attach to instrument 22 . Clip base 20 further includes pivot point 24 that attaches clip base 20 to clip arm 26 and enables clip arm 26 to rotate a certain degrees from and toward instrument 22 . In some embodiments, clip arm 26 is a shaft. The shaft may have any suitable design for use with magnetic spring clip system 100 such as without limitation a generally linear shape. In some embodiments, clip arm 26 may further have a threaded end away from the pivot point end of clip arm 26 . Such a threaded end may provide a means to attach clip magnet 28 to clip arm 26 . In other embodiments, clip magnet 28 may be a slide on magnet (e.g., slideably engaged with clip arm 26 ). In this embodiment, end cap 30 may attach to clip arm 26 via such threads to serve as a magnet stop. Second stop 32 is also positioned on clip arm 26 above clip magnet 28 . End cap 30 and second stop 32 help secure and prevent movement of clip magnet 28 . It is to be understood that there may be various types of instruments 22 to which magnetic spring clip 10 may be attached such as without limitation generally linearly shaped instruments. One such instrument may be a writing instrument with a magnetic clip as described in U.S. patent application Ser. No. 10/907,734 and another instrument may include a magnetic flashlight such as the flashlight disclosed in U.S. patent application Ser. No. 10/908,108, which are both incorporated by reference herein in their entirety.
[0027] It is to be understood that magnetic spring clip system 100 as shown in FIG. 2 does not reveal the magnet internal to instrument 22 . In one embodiment, clip arm 26 may be of a magnetic material. Further, surface 105 of instrument 22 may also be of a metal or magnetic material. In such embodiment, the magnetic force of clip arm 26 may cause clip arm 26 to be attracted to surface 105 of instrument 22 . As shown in FIG. 3 , in some embodiments, instrument 12 may contain internal magnet 34 that is aligned such that the magnetic field of internal magnet 34 forms an attraction to the magnetic field of clip magnet 28 on clip arm 26 .
[0028] FIGS. 3 and 4 conceptually show the different positions of magnetic spring clip system 100 . FIG. 3 shows magnetic spring clip system 100 in the closed position. This position is the normal or default position of magnetic spring clip 10 . In this position, clip magnet 28 attracts to internal magnet 34 . The attraction force (e.g., magnetic attraction) draws clip magnet 28 towards internal magnet 34 and surface 105 . In some instances, clip magnet 28 may actually contact surface 105 to provide the clamping action that holds objects inserted into magnetic spring clip system 100 to secure instrument 12 to the desired object.
[0029] FIG. 4 shows the position of magnetic spring clip system 100 in the open position. In this position, clip arm 26 is positioned at a distance from instrument 12 . However, because of the magnetic attraction between magnetic spring clip 10 and internal magnet 34 , a force may be applied to clip arm 26 to overcome the magnetic attraction of clip magnet 28 and internal magnet 34 in order to position clip magnet 28 in the open position. In the open position, material to which it is desired to attach instrument 12 is inserted between instrument surface 105 and clip arm 26 . At the release of clip arm 26 , the magnetic force may cause clip arm 26 to rotate toward and move clip magnet 28 toward internal magnet 34 , thereby clamping the inserted material and securing instrument 12 via magnetic spring clip 10 to the material.
[0030] FIG. 5 a shows a side view of magnetic spring clip system 100 in the closed position. Magnetic spring clip system 100 shows an embodiment of pivot point 24 . Also shown is an illustration of tapered top switch 40 . Switch 40 is used to turn on and turn off the light source for a lighting instrument. For a writing instrument, switch 40 may advance and retract the writing element of a writing instrument.
[0031] FIG. 5 b is a side cross-sectional view of magnetic spring clip system 100 . This embodiment is one in which magnetic spring clip 10 is attached to instrument 12 , which is in this embodiment a lighting instrument. In addition to the elements of magnetic spring clip system 100 , contained within instrument 12 is a pair of batteries 42 and 44 . Internal magnet 34 is positioned between batteries 42 , 44 . At the lower end of instrument 12 is light bulb 46 . Switch 40 may be a rotating switch as shown or a push switch. In the implementation of magnetic spring clip system 100 as illustrated in FIG. 5 b, internal magnet 34 may not interfere with operation of batteries 42 , 44 or electrical functions of instrument 12 .
[0032] FIG. 6 a is a side view of the pivot mechanism of magnetic spring clip 10 . In the pivot point mechanism, pivot rod 48 extends through clip arm 26 and attaches to walls 300 of clip base 20 . Clip arm 26 may be positioned in clip base 20 to provide greater flexibility and degrees for positioning clip arm 26 in the open position. Extension of portions of clip arm 26 toward switch 40 may restrict the degrees of the opening position. In FIG. 6 b, the amount of space 50 between clip base 20 and clip arm 26 also allows for the limited movement of clip arm 26 . The closer clip arm 26 is to the top of clip base 20 , the smaller the movement of clip arm 26 . As shown in FIG. 6 b, clip base 20 has walls 300 (e.g., a wall on each side), upper side 305 , and opening 310 suitable for receiving clip arm 26 (e.g., shaft).
[0033] FIG. 7 is a side view of an embodiment of magnetic spring clip system 100 with instrument 12 , which as illustrated is an illuminated writing instrument. In this embodiment, magnetic spring clip system 100 is implemented in an improved illuminated writing instrument 12 , which includes writing element 60 , lighting element 62 and attaching element 64 . Lighting element 62 contains internal magnet 66 . Clip magnet 28 magnetically attracts to instrument 12 . Writing element 60 and lighting element 62 are secured to each other via attaching element 64 . A suitable attaching element is disclosed in U.S. patent application Ser. No. 11/112,260, which is incorporated by reference herein in its entirety. Writing element 60 and lighting element 62 are secured to each other through openings in attaching element 64 . Attaching element 64 has an exterior surface formed of elastic grippers that provide increased stability between the user and the writing instrument. Attaching element 64 also has the capability to alter its shape in response to pressure from a user's fingers. The capability to alter the shape of attaching element 64 enables the user to easily and comfortably hold instrument 12 .
[0034] FIG. 8 is a side view of an alternate embodiment of magnetic spring clip system 100 implemented with instrument 12 , which in this embodiment is an illuminated writing instrument. In this embodiment, magnet spring clip system 100 is implemented in instrument 12 that includes writing element 80 , lighting element 82 , and attaching element 84 . Writing element 80 and lighting element 82 are secured to each other via attaching element 84 , which is disclosed in U.S. Pat. No. 7,101,103. U.S. Pat. No. 7,101,103 is incorporated by reference herein in its entirety. Attaching element 84 is a combination dual clip that attaches writing element 80 and lighting element 82 such that the two elements 80 , 82 form one illuminated writing instrument 12 . Magnetic spring clip system 100 further includes magnetic spring clip 10 to secure instrument 12 as desired by the user. In operation, the force from the magnetic field of clip magnet 28 attracts to the internal magnet (not illustrated) in lighting element 82 . This attraction may draw clip magnet 28 to the internal magnet. The attachment of clip magnet 28 and the internal magnet may secure clip arm 26 to the internal magnet thereby creating the mechanism that may provide the securing capabilities of magnetic spring clip 10 . Magnetic spring clip 10 may have the capability of securing instrument 12 as desired by the user. In alternative embodiments (not illustrated), attaching element 84 is a rubber grummet.
[0035] FIG. 9 is a side view of an alternate embodiment of magnetic spring clip system 100 attached to attaching element 84 , which is a dual clip. Clip base 20 attaches to attaching element 84 . In operation, the force from the magnetic field of clip magnet 28 attracts to the internal magnet (not illustrated) in instrument 12 . Such attraction may draw clip magnet 28 to the internal magnet. In this embodiment, clip arm 26 extends over attaching element 84 .
[0036] FIG. 10 illustrates clip magnet 28 and internal magnet 34 , which are each magnetized to have north and south poles. In an embodiment, internal magnet 34 has north pole 200 and south pole 205 , and clip magnet 28 has clip magnet north pole 210 and clip magnet south pole 215 . Internal magnet 34 is rotatable about its longitudinal axis within instrument 12 but is substantially fixed about the longitudinal axis of instrument 12 . In such an embodiment, clip magnet 28 is not rotatable about its longitudinal axis but has instead been attached to magnetic spring clip 10 with clip magnet north pole 210 distal to instrument 12 and clip magnet south pole 215 proximate to instrument 12 . In such an embodiment, when magnetic spring clip 10 is in the closed position as shown in FIG. 10 , the magnetic attraction of clip magnet south pole 215 attracts north pole 200 , and internal magnet 34 rotates about its longitudinal axis until north pole 200 is proximate to clip magnet south pole 215 . Therefore, north pole 200 is distal to the body of the individual, for instance when instrument 12 is placed in a pocket of the individual and secured to the pocket by magnetic spring clip 10 . Without being limited by theory, placing north pole 200 distal to the individual's body may prevent detrimental health issues to the individual that may be related to magnetic fields. For example, without being limited by theory, placing north pole 200 proximate to the individual's body may restrict blood flow in vessels exposed to the magnetic field exerted by north pole 200 , which may be a detrimental health effect. Such restriction may not occur with south pole 205 proximate to the body. In alternative embodiments, internal magnet 34 is not longitudinally rotatable but is instead fixed in position within instrument 12 , with north pole 200 proximate to clip magnet south pole 215 . In alternative embodiments (not illustrated), magnetic spring clip 10 further includes a shield. The shield may be composed of any material suitable for shielding a magnetic field. Without limitation, an example of such material is ferrous metal. The shield is disposed about a portion of the outside of clip magnet 28 . In an embodiment, the shield is disposed about a portion of the outside of clip magnet 28 that does not include the portion of clip magnet 28 that is in contact with instrument 12 when clip magnet 28 is in the closed position. The shield may be disposed about the outside of clip magnet 28 by any suitable method. For instance, the shield may be applied as a coating, manufactured to be disposed about the outside of clip magnet 28 , and the like. In such embodiments, the shield may provide a shield against at least a portion of the magnetic field of both clip magnet 28 and internal magnet 34 . In some embodiments, instrument 12 may also include such a shield about a portion of surface 105 . In such embodiments, the shield may leave exposed at least a portion or substantially all of the portion of surface 105 that is a contact point with clip magnet 28 . In embodiments, the shield may provide a shield against at least a portion of the magnetic field of both clip magnet 28 and internal magnet 34 .
[0037] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the spirit and scope of the invention as defined by the appended claims. | A magnetic spring clip and system are disclosed. In an embodiment, a magnetic spring clip includes a clip base having a semi-circle shape with an opening for engaging an instrument. The magnetic spring clip also includes a pivot point within the clip base. In addition, the magnetic spring clip includes a shaft having a generally linear shape and upper and lower ends. The upper end of the shaft is attached to the clip base by the pivot point such that the shaft is moveable relative to the clip base. Moreover, the shaft farther includes a magnetic lower end. The magnetic lower end is magnetically attracted to the instrument such that the lower end of the shaft contacts the instrument and secures any material between the lower end of the shaft and the instrument. The magnetic spring clip also has a clip magnet, wherein the clip magnet has a magnetic south pole and a magnetic north pole. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention related to a new process for the preparation of the compounds of the formula 1 (where R 1 and R 2 represent C 1 -C 4 alkyl group) and their hydrochloride thereof, and other various pharmaceutical used salts. The process is more efficient than the reported processes in total yield and reaction steps for the synthesis of compounds having the formula 1. In the present invention, the use of optically pure starting material can provide the desired compound in more specific range to meet the pharmaceutical requirement. Furthermore, the shorter reaction steps will provide the desired drugs with limit scope of impurity profile.
2. Description of the Prior Art
It is described in the U.S. Pat. No. 5,447,958 that the compounds of the above formula 1 have excellent therapeutic effects against hypertension, congestive heart failure, angina pectoris or prostatic hypertrophy. In addition, the above patent disclosed a process for the preparation of compounds with the formula 1 by reacting following hydrochlorides of sulfonamide 2A with bromide 3:
Wherein, sulfonamide hydrochloride salt 2B (hydrochloride of formula 2A) can be synthesized from the Process 1 depicted below. The synthetic procedure of Process 1 involves phenylamine 4A as the starting material to produce the intermediates of acetamide 5A and (sulfo)acetamide 6A, and then to give sulfonamide hydrochloride salt 2B.
Process 1:
The synthesis of phenylamine 4A was disclosed in U.S. Pat. No. 4,000,197 and J. Med. Chem. 1973, 16, 480-483 by condensation of 4-methoxyphenylacetone with (R)-α-methylbenzylamine, followed by hydrogenation of the N═N double bond therein, and reductive debenzylation. The total yield for the preparation of phenylamine 4A is 25% with >99% enantiomeric purity.
Yamada et al. described a process for the synthesis of phenylamine 4A in Synth. Commun. 1998, 28, 1935-1945 by using optically pure L-tyrosine as the starting material. The advantage of the current process is that the resultant product is optically pure. The preparation of intermediate 4B (hydrochloride of phenylamine 4A) involves overall 8 steps, and if extended to intermediate 5A, would be 9 steps. Yamada's procedure is depicted in Process 2 as below:
Process 2:
The synthetic procedure of Process 2 uses L-tyrosine 7 as the starting material to generate the intermediates of aminoester 8, (phenol)amidoester 9, (ether)amidoester 10, (hydroxy)ether amide 11, tosyl amide 12, iodide 13, ether amide 14, and finally to obtain hydrochloride of phenylamine 4B.
SUMMARY OF THE INVENTION
The present invention relates to a new process for the synthesis of sulfamoyl-substituted phenoethylamine derivatives and the acidic salts thereof, especially the tamsulosin derivatives having the following formula 1 (where R 1 and R 2 represent C 1 -C 4 alkyl group) or their hydrochloride thereof, and other various pharmaceutical used salts.
As mentioned before, the synthesis of tamsulosin 1 (R 1 =Et and R 2 =Me) involves a key intermediate, i.e. acetamide 5A. Herein, the invention discloses a new process, as shown in Process 3, for the preparation of the key intermediate 5A as depicted below, where comprises the new intermediates, such as (phenol)amido acid 15A, (phenol)amidoester 16A, (ether)amidoester 17A, hydroxy(ether)amide 18A.
Process 3:
The process is more efficient than the reported processes in total yield and reaction steps for the synthesis of compounds having the formula 1. Furthermore, in the invention, the use of optically pure starting material can provide the desired compound in more specific range to meet the pharmaceutical requirement. And the shorter reaction steps will provide the desired drugs with limit scope of impurity profile.
A new key intermediate (ether)benzoxy tosylate 21A, instead of bromide 3, for the preparation of formula 1 is also disclosed in the invention. It involves the use of 2-ethoxyphenol (19A) as the starting material. Sequential reaction of 19A with chloroethanol and toluenesulfonyl chloride will provide the key intermediate 21A via (ether)benzoxy alcohol 20A. The advantages associated with the use of (ether)benzoxy tosylate 21A instead of bromide 3 will simplify the manipulation of the reaction and, to a more important reason, avoid the pollution resulting from the hazardous halogenated wastes. The process for the preparation of (ether)benzoxy tosylate 21A is depicted as shown in Process 4.
Process 4:
The intermediate acetamide 5A was converted to (sulfo)acetamide 6A and then to sulfonamide hydrochloride salt 2B by the established methods. Sulfonamide hydrochloride salt 2B was allowed to react with (ether)benzoxy tosylate 21A to generate the desired tamsulosin (1, R 1 =Et, R 2 =Me). The synthesis of tamsulosin is depicted as shown in Process 5.
Process 5:
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention relates to a new process for the synthesis of sulfamoyl-substituted phenoethylamine derivatives and the acidic salts thereof.
A process for the preparation of (phenol)amido acid 15 from starting material L-tyrosine 7 is shown in Process 6.
Process 6:
Additionally, an acylating agent and a solvent are used; the acylating agent is selected from RCOX, (RCO) 2 O and the combination thereof, wherein R is alkyl or aryl; X is a halide or a leaving group; the solvent is selected from alkanes, ethers, DMF, DMSO, ketones, urea and the combination thereof.
A process for the preparation of (phenol)amidoester 16 from (phenol)amido acid 15 is shown in Process 7.
Process 7:
Additionally, an acid chloride and a R′OH are used; the acid chloride is selected from the group of PCl 3 , PCl 5 , POCl 5 , SOCl 2 , oxalyl chloride and the combination thereof; the R and R′ groups are alkyl or aryl.
Furthermore, a process for the preparation of (ether)amidoester 17 from (phenol)amidoester 16 is shown in Process 8.
Process 8:
Additionally, an alkylating agent, a base and a solvent are used; the alkylating agent is selected from R 2 SO 4 , RI, RBr and the combination thereof; the base is selected from amines, carbonates, hydrogen carbonates, amides, alkoxides and the combination thereof; the solvent is selected from H 2 O, ketones, alkanes, ethers, DMF, DMSO, urea and the combination thereof.
A process for the preparation of hydroxy(ether)amide 18 from (ether)amidoester 17 is shown in Process 9.
Process 9:
Additionally, a reducing agent and a solvent are used; the reducing agent is selected from LiAlH 4 , DIBAL, K-selectride, L-selectride, BH 3 , NaBH 4 and the combination thereof; the solvent is selected from ethers, alcohols, H 2 O, alkanes, DMF, DMSO, urea and the combination thereof.
As shown in Process 10, acetamide 5 can be prepared from hydroxy(ether)amide 18.
Process 10:
Wherein, an acid halide, a solvent, an organic acid, MXn and M are used; the acid halide is selected from the group of TsCl, MsCl, SOCl 2 , SO 2 Cl 2 , PCl 3 , PCl 5 , POCl 5 , oxalyl chloride and the combination thereof; the solvent is selected from THF, ketones, alkanes, ethers, DMF, DMSO, CH 2 Cl 2 , CHCl 3 , CCl 4 , urea and the combination thereof, the organic acid is selected from oxalic acid (COOH) 2 , RCOOH and the combination thereof, where R is H, alkyl, or aryl; the M is selected from Li, Na, K, Mg, Ca, Zn, Pt, Pd, Cu, Co, Mn, Fe, Ni, or Cd; the X is Cl, Br, I, or OAc; the n value is 1-3 based on the valence of the metal.
As mentioned before, the synthesis of tamsulosin 1 involves a key intermediate acetamide 5. Herein, the invention could prepare tamsulosin 1 from acetamide 5.
The present invention can be further understood by the following examples, which are used to illustrate the present invention, but not to limit the scope thereof.
EXAMPLE 1
To a solution of L-tyrosine 7 (20.01 g, 110.4 mmol) in H 2 O (120 mL) was added acetic anhydride (13.51 g, 132.4 mmol). After being heated at reflux for 4.0-5.0 h, the solution was concentrated by distillation to give a light yellow syrupy residue. The residue was dissolved in acetone (80 mL) and the unreacted L-tyrosine 7 was removed by filtration. The filtrate was concentrated under the reduced pressure and the residue was redissolved in ethyl acetate (100 mL), washed with water (50 mL), dried over MgSO 4 (s), and concentrated under reduced pressure to obtain (phenol)amido acid 15A (17.62 g, 78.93 mmol) as gel-like semi-solid in 71% crude yield: mp (recrystallized from MeOH) 152-153° C.; specific rotation α D 20 =+50.9720°; 1 H NMR (D 2 O, 400 MHz) δ 2.07 (s, 3 H, COCH 3 ), 2.82-2.86 (m, 1 H, ArCHH), 2.96-3.01 (m, 1 H, ArCHH), 3.67-3.70 (m, 1 H, CHCOO), 6.70 (d, J=8.0 Hz, 2 H, ArH), 7.01 (d, J=8.0 Hz, 2 H, ArH); IR (neat) 3207 (s), 2961 (m), 1609 (s), 1591 (s), 1513 (s), 1455 (s), 1417 (s), 1363 (s), 1331 (s), 1267 (m), 1245 (s), 1214 (m), 1154 (m), 1112 (m), 1099 (m), 1042 (m), 984 (w), 939 (w), 897 (w), 877 (m), 841 (s), 794 (m), 740 (m), 713 (w), 649 (m), 575 (s), 529 (s), 493 (m), 433 (m) cm −1 .
EXAMPLE 2
To a solution of (phenol)amido acid 15A (10.01 g, 44.84 mmol) in ethanol (300 mL) was added phosphorus trichloride (18.46 g, 134.4 mmol) dropwisely under ice-salt cooling (5° C.) over a period of 60 min. After being stirred at room temperature overnight, the reaction mixture was concentrated under reduced pressure. The residue was dissolved in ethyl acetate (50 mL), washed with water and saturated aqueous NaHCO 3 (25 mL), dried over MgSO 4 (s), and concentrated under reduced pressure to obtain (phenol)amidoester 16A (8.225 g, 32.73 mmol) as pale yellow solids in 73% crude yield: mp (recrystallized from 50% EtOAc in hexanes) 126.0-128.0° C.; specific rotation α D 20 =−1.7632°; 1 H NMR (CDCl 3 , 400 MHz) δ 1.24 (t, J=6.8 Hz, 3 H, CH 2 CH 3 ), 1.97 (s, 3 H, COCH 3 ) 2.95-3.08 (m, 2 H, ArCH 2 ), 4.16 (q, J=6.8 Hz, 2 H, COCH 2 ), 4.79-4.82 (m, 1 H, CHCOO), 6.71 (d, J=8.0 Hz, 2 H, ArH), 6.94 (d, J=8.0 Hz, 2 H, ArH); IR (neat) 3384 (br), 3020 (m), 2927 (m), 2851 (m), 1733 (s), 1652 (s), 1615 (s), 1542 (m), 1516 (s), 1446 (m), 1376 (m), 1219 (s), 1125 (w), 1026 (w), 828 (w), 769 (s), 668 (m), 518 (m) cm −1 .
EXAMPLE 3
To a solution of (phenol)amidoester 16A (8.021 g, 31.92 mmol) in acetone (35 mL) was added triethylamine (7.365 g, 72.78 mmol) and dimethyl sulfate (5.473 g, 43.39 mmol). After being stirred at 25° C. for 20 h, the solution was quenched with water (50 mL) and extracted with toluene (50 mL). The organic layer was washed with 10% aqueous NaOH (25 mL) and brine (25 mL), dried over MgSO 4 (s), filtered, and concentrated under reduced pressure to obtain (ether)amidoester 17A (7.113 g, 26.81 mmol) as light brown semi-solids in 84% crude yield: mp (recrystallized from EtOAc) 140-142° C.; specific rotation α D 20 =−1.6950°; 1 H NMR (CDCl 3 , 400 MHz) δ 1.21 (t, J=6.8 Hz, 3 H, CH 2 CH 3 ), 1.92 (s, 3 H, COCH 3 ), 3.02-3.09 (m, 2 H, ArCH 2 ), 3.95 (s, 3 H, OCH 3 ), 4.14 (q, J=6.8 Hz, 2 H, COCH 2 ), 4.76-4.81 (m, 1 H, CHCOO), 6.76 (d, J=8.0 Hz, 2 H, ArH), 7.02 (d, J=8.0 Hz, 2 H, ArH); IR (neat) 3282 (m), 3075 (w), 2968 (m), 2933 (m), 2837 (w), 1716 (w), 1651 (s), 1614 (s), 1557 (s), 1514 (s), 1456 (s), 1374 (s), 1300 (m), 1248 (s), 1178 (m), 1146 (w), 1114 (w), 1035 (m), 975 (w), 815 (w), 775 (w), 608 (w), 562 (w), 523 (w), 419 (w) cm −1 .
EXAMPLE 4
To a stirred solution of LiAlH 4 (1.014 g, 26.72 mmol) in diethyl ether (140 mL) was added (ether)amidoester 17A (7.088 g, 26.72 mmol) in diethyl ether (50 mL) under ice water cooling at 10° C. After the solution was stirred at 25° C. for 10 h, the reaction mixture was neutralized with HCl (12 N, 10 mL) and filtered, and the filtrate was concentrated under reduced pressure. The residue was re-dissolved in ethyl acetate (200 mL), washed with water (20 mL), 10% aqueous NaOH (20 mL), brine (20 mL), dried over MgSO 4 (s), filtered, and concentrated under reduced pressure to obtain hydroxy(ether)amide 18A (3.579 g, 16.03 mol) as white solids in 60% crude yield: mp (recrystallized from EtOAc and hexanes) 129-130° C.; specific rotation α D 20 =−10.9440°; 1 H NMR (CDCl 3 , 400 MHz) δ 1.95 (s, 3 H, NCOCH 3 ), 2.40 (br, 1 H, OH), 2.75-2.85 (m, 2 H, ArCH 2 ), 3.57-3.67 (m, 2 H, CH 2 O), 3.74 (s, 3 H, OCH 3 ), 4.08-4.14 (m, 1 H, CHN), 6.84 (d, J=8.4 Hz, 2 H, ArH), 7.12 (d, J=8.4 Hz, 2 H, ArH); IR (neat) 3512 (br), 3002 (w), 2948 (m), 2834 (m), 1892 (w), 1645 (s), 1577 (m), 1551 (m), 1511 (s), 1441 (m), 1377 (m), 1300 (s), 1245 (s), 1177 (s), 1083 (m), 1041 (s), 821 (m), 614 (m) cm −1 .
EXAMPLE 5
To a solution of hydroxy(ether)amide 18A (10.01 g, 44.83 mmol) in THF (50 mL) was added toluenesulfonyl chloride (15.67 g, 82.19 mmol). After being stirred atreflux for 1.5 h, the reaction mixture was slowly poured into saturated aqueous K 2 CO 3 solution. The aqueous layer was extracted with ethyl acetate (3×20 mL) and the combined organic layer was washed with water (80 mL), dried over MgSO 4 (s), and concentrated under reduced pressure. The residue was dissolved in THF (160 mL) containing oxalic acid (20 g) and LiBr (8.118 g, 93.47 mmol) was added. After being stirred at reflux for 10 min, the solution was added with Li (wire, 1.488 g, 214.4 mmol). The resultant solution was stirred at the same temperature for 2.0 h, filtered through celite, washed with ethyl acetate, and concentrated under reduced pressure. The residue was dissolved into water (50 mL), neutralized with K 2 CO 3 (s, 20.01 g), and extracted with ethyl acetate (5×80 mL). The organic layer was washed with water (40 mL) and concentrated under reduced pressure. The residue was added with water (20 mL), kept for overnight, filtered, and dried under vacuum to obtain acetamide 5A (6.711 g, 32.37 mmol) as white solids in 72% crude yield: mp (recrystallized from EtOAc) 90-91° C.; specific rotation α D 20 =+9.9083°; 1 H NMR (CDCl 3 , 300 MHz) δ 1.08 (d, J=5.4 Hz, 3 H, CCH 3 ), 1.92 (s, 3 H, COCH 3 ), 2.60-2.77 (m, 2 H, ArCH 2 ), 3.76 (s, 3 H, OCH 3 ), 4.10-4.25 (m, 1 H, CHMe), 6.81 (d, J=7.8 Hz, 2 H, ArH), 7.06 (d, J=7.8 Hz, 2 H, ArH); IR (neat) 3276 (br), 3077 (m), 2969 (m), 2933 (m), 2836 (m), 1716 (m), 1647 (s), 1615 (s), 1542 (s), 1513 (s), 1456 (m), 1374 (m), 1300 (m), 1247 (s), 1178 (m), 1035 (m), 814 (m), 755 (w), 518 (w), 420 (w) cm −1 .
EXAMPLE 6
To acetamide 5A (1.01 g, 4.81 mmol) was added chlorosulfonic acid (10.1 g, 85.8 mmol) under cooling at 0-10° C. The solution was stirred at 5.0° C. for 1.0 h. The reaction mixture was slowly poured into ice water and the resultant oily material was extracted with ethyl acetate (100 mL). The organic layer was washed with saturated aqueous NaHCO 3 (25 mL), H 2 O (10 mL), dried over MgSO 4 (s), filtered, and concentrated under reduced pressure. The residue was redissolved in THF (20 mL), added with concentrated aqueous ammonia solution (15 N, 30 mL), and stirred at 25° C. for 1.0 h. The solution was concentrated under reduced pressure, and the resultant residue was washed with water (2.0 mL) and dried under reduced pressure to obtain (sulfo)acetamide 6A (602.1 mg, 2.102 mmol) as white solids in 44% crude yield: mp (recrystallized from MeOH) 198-199° C.; specific rotation α D 20 =+13.2634°; 1 H NMR (D 2 O, 400 MHz) δ 0.99 (d, J=6.8 Hz, 3 H, CCH 3 ), 1.68 (s, 3 H, COCH 3 ), 2.43-2.49 (m, 1 H, ARCHH), 2.69-2.74 (m, 1 H, ArCHH), 3.72 (s, 3 H, OCH 3 ), 3.80-3.86 (m, 1 H, CHMe), 7.01 (d, J=8.8 Hz, 1 H, ArH), 7.33 (d, J=8.8 Hz, 1 H, ArH), 7.48 (s, 1 H, ArH); IR (neat) 3132 (br), 1654 (s), 1609 (m), 1536 (m), 1496 (m), 1401 (s), 1320 (m), 1283 (m), 1253 (m), 1176 (w), 1148 (s), 1070 (m), 1024 (m), 977 (w), 927 (w), 860 (w), 838 (w), 828 (w), 761 (m), 701 (w), 669 (w), 614 (m), 599 (m), 572 (m), 535 (m), 505 (m), 450 (m) cm −1 ; ESI-MS m/z 287.27 (M+H + ).
EXAMPLE 7
An aqueous HCl solution (5.0%, 25 mL) containing (sulfo)acetamide 6A (0.541 g, 1.88 mmol) was heated at reflux for 16 h. The solution was concentrated under reduced pressure, redissolved in hot MeOH (3.0 mL), and slowly added with ethyl acetate (10 mL). The precipitate was collected and dried under vacuum to obtain sulfonamide hydrochloride salt 2B (0.449 g, 1.60 mmol) as white solids in 85% yield: mp (recrystallized from MeOH) 272-273° C. (dec.); specific rotation α D 20 =−9.2040°; 1 H NMR (D 2 O, 400 MHz) δ 1.14 (d, J=6.4 Hz, 3 H, CCH 3 ), 2.79-2.82 (m, 2 H, ArCH 2 ), 3.43-3.56 (m, 1 H, CHMe), 3.84 (s, 3 H, OCH 3 ), 7.10 (d, J=8.4 Hz, 1 H, ArH), 7.42 (d, J=8.4 Hz, 1 H, ArH), 7.58 (s, 1 H, ArH); IR (neat) 3329 (s), 3196 (s), 3150 (s), 3025 (s), 2944 (s), 2701 (w), 2590 (w), 2501 (w), 1611 (m), 1553 (m), 1496 (s), 1402 (s), 1327 (s), 1282 (m), 1255 (m), 1154 (s), 1075 (m), 1017 (m), 928 (m), 828 (w), 804 (m), 703 (m), 601 (s), 572 (m), 536 (m), 507 (m) cm −1 ; ESI-MS m/z 245.15 (M+H + ); Anal. Calcd for C 10 H 17 N 2 O 3 SCl: C, 42.78; H, 6.10; N, 9.98. Found: C, 42.76; H, 6.15; N, 9.93.
EXAMPLE 8
To a solution of 2-ethoxyphenol 19A (13.82 g, 100.1 mmol) in aqueous NaOH (1.0 N, 300 mL) was added chloroethanol (33.12 mL, 500.1 mmol). After being stirred at 25° C. for 48 h, the reaction mixture was extracted with ethyl acetate (3×100 mL). The organic layer was dried over MgSO 4 (s), filtered, and concentrated under reduced pressure to obtain (ether)benzoxy alcohol 20A (14.02 g, 76.94 mmol) as yellow liquid in 77% yield: 1 H NMR (CDCl 3 , 400 MHz) δ 1.44 (t, J=7.2 Hz, 3 H, OCH 2 CH 3 ), 3.85 (t, J=7.2 Hz, 2 H, CH 2 OH), 4.05-4.12 (m, 4 H, OCH 2 CH 3 +OCH 2 CH 2 OH), 6.88-6.97 (m, 4 H, ArH); IR (neat) 3547 (br), 3066 (m), 2977 (s), 2931 (s), 2877 (s), 1739 (m), 1649 (m), 1593 (s), 1503 (s), 1455 (s), 1393 (m), 1324 (m), 1253 (s), 1219 (s), 1123 (s), 1041 (s), 922 (s) cm −1
EXAMPLE 9
To a solution of (ether)benzoxy alcohol 20A (501.2 mg, 2.751 mmol) in CH 2 Cl 2 (20 mL) was added Et 3 N (509 mg, 5.03 mmol) and toluenesulfonyl chloride (623 mg, 3.27 mmol) at 5-10° C. After being stirred at 25° C. for 30 min, the reaction mixture was quenched with saturated aqueous Na 2 CO 3 (20 mL) and extracted with ethyl acetate (3×50 mL). The combined organic layers were dried over MgSO 4 (s), filtered, and concentrated under reduced pressure to obtain (ether)benzoxy tosylate 21A (853.5 mg, 2.539 mmol) as white solids in 92% yield: mp (recrystallized from CH 2 Cl 2 and CCl 4 ) 82-83° C.; 1 H NMR (CDCl 3 , 300 MHz) δ 1.43 (t, J=10.2 Hz, 3 H, OCH 2 CH 3 ), 2.51 (s, 3 H, ArCH 3 ), 4.04 (q, J=10.2 Hz, 2 H, OCH 2 CH 3 ), 4.36 (t, J=6.9 Hz, 2 H, OCH 2 CH 2 ), 4.59 (t, J=6.9 Hz, 2 H, OCH 2 CH 2 ), 6.86-6.97 (m, 4 H, ArH), 7.10-7.22 (m, 4 H, ArH); IR (neat) 3446 (br), 2982 (m), 2934 (m), 2884 (m), 1591 (s), 1558 (w), 1509 (s), 1478 (s), 1454 (s), 1407 (s), 1394 (s), 1371 (s), 1354 (s), 1279 (m), 1259 (s), 1247 (s), 1217 (s), 1178 (s), 1127 (s), 1066 (s), 1043 (s), 1031 (s), 977 (s), 929 (s), 905 (s), 809 (s), 776 (m), 749 (s), 776 (m) cm −1
EXAMPLE 10
To a solution of sulfonamide hydrochloride salt 2B (1.12 g, 4.00 mmol) in EtOH (40 mL) was added NaHCO 3 (672 mg, 8.00 mmol). After being stirred at room temperature for 5.0 min, the solution was added with (ether)benzoxy tosylate 21A (1.34 g, 4.00 mmol). The solution was stirred at 90-100° C. for 22 h. The reaction mixture was cooled to room temperature, filtered, concentrated under reduced pressure, and dried under vacuum. The resultant semi-solid was dissolved in CH 2 Cl 2 (50 mL), filtered, and the solid was washed with CH 2 Cl 2 (3×5.0 mL). The residual solid was recovered as the unreacted sulfonamide 2A. The filtrate was concentrated under reduced pressure, and the residue was dissolved in CHCl 3 (50 mL) and washed with water (3×25 mL). The aqueous solution was added with brine and then extracted with EtOAc to obtain the unreacted sulfonamide 2A. The organic layer was dried over MgSO 4 (s), filtered, and concentrated under reduced pressure. The residue was dried under vacuum and the solid was washed with CCl 4 (3×20 mL). Ethoxyphenol 19 was recovered by concentration of the CCl 4 solution. The solid was purified by column chromatography on silica gel (37% MeOH in CHCl 3 as eluant) to obtain tamsulosin 1 (571 mg, 1.40 mmol) as white solids in 35% yield: mp (recrystallized from CH 2 Cl 2 and EtOAc) 129-131° C.; specific rotation α D 20 =−14.7240°; 1 H NMR (CD 3 OD, 400 MHz) δ 0.99 (d, J=6.4 Hz, 3 H, NCHCH 3 ), 1.28 (t, J=7.2 Hz, 3 H, OCH 2 CH 3 ), 2.49-2.54 (m, 1 H, ArCHH), 2.77-2.82 (m, 1 H, ArCHH), 2.89-2.98 (m, 3H, NCH 2 +NCH), 3.88 (s, 3 H, OCH 3 ), 3.93-4.57 (m, 4 H, CH 2 CH 2 O+CH 3 CH 2 O), 6.81-6.89 (m, 4H, ArH), 7.03 (d, J=8.4 Hz, 1 H, ArH), 7.36 (d, J=8.4 Hz, 1 H, ArH), 7.63 (s, 1 H, ArH); IR (neat) 3284 (m), 2973 (m), 2939 (m), 1592 (m), 1504 (s), 1442 (m), 1324 (s), 1282 (m), 1249 (s), 1214 (m), 1154 (s), 1125 (m), 1073 (m), 1046 (m), 971 (w), 925 (m), 753 (m) cm −1 ; ESI-MS m/z 409.40 (M+H + ).
EXAMPLE 11
To a solution of tamsulosin 1 (2.011 g, 4.917 mmol) in CH 2 Cl 2 (50 mL) was bubbled with excess dry HCl (g) at 0-5° C. for 1.0 h. The resultant precipitate was filtered and dried under vacuum at room temperature to obtain tamsulosin•HCl (2.091 g, 4.699 mmol) as white solids in 96% yield: mp (recrystallized from 50% MeOH in EtOH) 230-231° C.; specific rotation α D 20 =−5.3843°; 1 H NMR (D 2 O, 400 MHz) δ 1.14-1.17 (m, 6 H, NCHCH 3 +OCH 2 CH 3 ), 2.71-2.76 (m, 1 H, ArCHH), 2.95-3.00 (m, 1 H, ArCHH), 3.36-3.43 (m, 2 H, NCH 2 ), 3.53-3.55 (m, 1 H, NCH), 3.75 (s, 3 H, OCH 3 ), 3.94-3.97 (m, 2 H, MeCH 2 O), 4.04-4.19 (m, 2 H, OCH 2 CH 2 ), 6.84-6.96 (m, 5 H, ArH), 7.35 (d, J=8.8 Hz, 1 H, ArH), 7,54 (s, 1 H, ArH); IR (neat) 3304 (m), 3168 (m), 2981 (m), 1610 (m), 1589 (m), 1500 (s), 1458 (m), 1392 (m), 1339 (s), 1251 (s), 1215 (s), 1160 (s), 1128 (s), 1072 (m), 1046 (m), 1018 (m), 820 (m), 749 (s), 718 (m) cm −1 .
In the present invention a process for preparation of tamsulosin and its aralkylamine derivatives is disclosed. The steps for preparation of tamsulosin from starting material L-tyrosine are fewer and the yield is higher than that of the conventional method, meanwhile, the key intermediates 15A to 18A as synthesized during tamsulosin 1 preparation are also representative intermediates for the present invention.
Those embodiments described above are only to clarify the technical contents and characteristics of the present invention so that the persons skilled in the art can understand, make, and use the present invention but not intended to limit the scope of the present invention. Any equivalent modification and variation according to the spirit of the present invention is to be included within the scope of the present invention. | The present invention discloses a new process for the synthesis of tamsulosin and its aralkylamine derivatives, especially (R)-(−)-5-{2-[2-(2-alkoxyphenoxy) ethylamino]propyl}-2-alkoxybenzenesulfonamides having the following formula 1 (where R 1 and R 2 represent C 1 -C 4 alkyl groups) and their hydrochloride thereof, and other various pharmaceutical used salts.
Tamsulosin hydrochloride (R 1 =Et, R 2 =Me, in its hydrochloride salt form) is an antagonist of α-A adrenoceptors in the prostate. Tamsulosin•HCl occurs as white crystals, which melt with decomposition at approximately 230° C. It is sparingly soluble in water and in methanol, slightly soluble in glacial acetic acid and in ethanol, and practically insoluble in ether. | 2 |
TECHNICAL FIELD
The present invention relates to hydraulic valve lifters for use with internal combustion engines, more particularly, to an anti-rotation guide which prevents rotation of a deactivation hydraulic valve lifter in a push-rod internal combustion engine, and even more particularly, to an anti rotation guide that minimizes frictional loss between the guide and the lifter body of a deactivation hydraulic valve lifter.
BACKGROUND OF THE INVENTION
Cylinder deactivation during at least a portion of the combustion process is a proven method by which fuel economy can be improved. With fewer cylinders performing combustion, fuel efficiency is increased and the amount of pollutants emitted from the engine is reduced. A known method of providing cylinder deactivation in a push rod engine is by using a deactivation mechanism in the hydraulic valve lifter.
A hydraulic valve lifter, whether of the deactivating or non-deactivating type, slides reciprocally in an engine bore. The lifter engages a camshaft lobe via a camshaft follower which typically is a roller follower. Unless suitably guided by an anti-rotation mechanism, the lifter may rotate in its bore during reciprocation, thereby undesirably misaligning its follower from the associated cam lobe.
One version of a prior art anti-rotation guide that prevents rotation of a standard (non-deactivation) hydraulic roller lifter is in the form of a flat plate having apertures for receiving the lifter bodies. The apertures are sized to freely permit reciprocation of the lifter in the guide plate and include a flatted portion along each aperture periphery to matingly engage a flatted portion on each lifter body to prevent the lifter from rotating during reciprocation. In the flat plate version, each lifter must first be individually inserted into its respective engine bore. Then, the plate is positioned on the engine, each guide plate aperture receiving a lifter in its proper rotational orientation. Lastly, the plate is rigidly secured to the engine thereby preventing the lifters from rotating during engine operation.
Another version of a prior art anti-rotation guide used to keep the follower of a standard hydraulic lifter in alignment with the cam lobe is disclosed in U.S. Pat. No. 5,088,455. In that version, the guide is used to also “kit” a bank of lifters prior to engine assembly by snuggly gripping a portion of the lifter body via a substantial interference fit across flatted segments of the lifter body. Because the guide snuggly grips each lifter, a significant frictional drag is created between the lifter and guide which can impede hydraulic recovery of the lifter's hydraulic plunger assembly after being drained of oil during shutdown. In some non-deactivation lifters, frictional drag from the interference fit of a gripping guide can be readily compensated for by increasing the size and internal spring force of the hydraulic plunger assembly. However, because of size constraints placed on the deactivation lifter design, this remedy cannot be readily applied to a deactivation lifter assembly.
In addition, deactivation lifters, as known in the prior art, require a specific rotational orientation to mate with a deactivation oil passage in the engine. A single flat on the lifter body for mating with a corresponding flat on the guide would assure proper alignment with the engine oil passage. However, with only a single flat, some amount of anti-rotation protection is lost. Greater anti-rotation protection could be provided via two opposing flats, but this would defeat the orientation preference needed by deactivation lifters as conferred by a single flat.
Finally, anti-rotation guides known in the art, and used with standard hydraulic lifters, are closed-ended, providing only a clearance orifice for the associated push rod to reciprocate through the guide. Such a guide cannot accommodate a deactivation hydraulic lifter having an external spring tower which is substantially greater in diameter than the push rod.
Therefore, what is needed in the art is an anti-rotation guide which accommodates a deactivation lifter and prevents the hydraulic lifter from rotating in its bore during reciprocation.
What is further needed in the art is an anti-rotation guide which minimizes friction and binding between the guide and the deactivation lifter while also retaining the lifter for kitting purposes.
SUMMARY OF THE INVENTION
The present invention provides an anti-rotation guide for a deactivation hydraulic valve lifter.
A guide in accordance with the invention is a funnel-shaped element having walls tapering from a larger opening to a smaller opening accommodating of a deactivation hydraulic valve lifter. The smaller opening is sized such that an end of the lifter, which on a deactivation lifter includes the spring tower, may be inserted through the opening and into the guide. The shape of the element permits articulation of a pushrod engaged with the lifter. The guide is fixedly securable to the engine such that the lifter is reciprocable within the guide.
The smaller opening of the guide is provided with guide keepers having two flats for mating with corresponding flats on the lifter to prevent rotation of the lifter. In the present invention, the keepers serve to engage an outer ridge portion on the lifter and thereby loosely hold the lifters in place in the guide (“kitting”) during engine assembly. The guide flats are preferably formed in an hourglass shape to permit a degree of angular movement of the lifter relative to the guide to prevent binding during reciprocation. Further, a groove is provided in the guide opening or lifter for receiving a longitudinal rib on the mating part to prevent the lifter from being inserted into the guide 180° from the correct orientation. Preferably, the mating walls of the groove and rib of the present invention are formed perpendicular to the flats on the lifter to provide greater resistance to lifter rotation during engine operation.
Further, ramped flutes disposed longitudinally along the inner walls of the guide opening are provided to center the pushrod into the lifter during assembly. The inside diameter of the lost motion spring tower is stepped as well to aid in centering of the pushrod and to provide operational clearance to the pushrod.
In a currently-preferred embodiment, anti-rotation guides are provided in guide elements comprising four guides for four valves, two intake and two exhaust, for economy of manufacture and installation. Each of the guides are preferably equipped with a lifter in a pre-assembled kit which then is inserted directly into the engine during assembly thereof, the correct rotational orientation of the lifters and lifter position relative to respective cylinders thus being assured.
An advantage of the present invention is that the anti-rotation retains the lifter prior to engine installation.
A further advantage of the present invention is that, once installed, the anti-rotation guide tightly constrains the deactivation lifter rotationally but loosely constrains the lifter axially such that minimal frictional resistance is encountered during axial actuation of the lifter.
Yet another advantage of the present invention is that a means is provided in the anti-rotation guide to permit a degree of angular movement of the lifter relative to the guide.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the invention will be more fully understood and appreciated from the following description of certain exemplary embodiments of the invention taken together with the accompanying drawings, in which:
FIG. 1 is a partially sectioned, perspective view of a deactivation roller hydraulic valve lifter used in conjunction with an anti-rotation guide in accordance with the present invention;
FIG. 2A is an axially-sectioned view of the lifter body of FIG. 1 ;
FIG. 2B is an axially-sectioned view of the lifter body of FIG. 1 rotated by 90 degrees;
FIG. 3 is an axially-sectioned view of FIG. 1 ;
FIG. 4 is an axially-sectioned view of the pin housing, plunger assembly, and push rod seat of FIG. 1 ;
FIG. 5 is an axially-sectioned view of an anti-rotation guide and deactivation roller hydraulic valve lifter in accordance with the present invention;
FIG. 6 is a perspective view of a multiple anti-rotation guide element assembly in accordance with the invention, shown with two deactivating valve lifters and two standard valve lifters installed in the anti-rotation guide element;
FIG. 7 is an elevational view of the guide element assembly shown in FIG. 6 ;
FIG. 8 is a vertical cross-sectional view of the guide element assembly shown in FIG. 6 , taken along line 8 — 8 in FIG. 10 ;
FIG. 9 a is a vertical cross-sectional view taken along line 9 — 9 in FIG. 10 , substantially equivalent to FIG. 5 showing the lifter on base circle;
FIG. 9 b is a vertical cross-sectional view taken along line 9 — 9 in FIG. 10 showing the lifter at maximum cam lift;
FIG. 10 is a plan view of the guide element assembly shown in FIGS. 6 and 7 ;
FIG. 11 is a cross-sectional view taken along line 11 — 11 in FIG. 5 ; and
FIG. 12 is a magnified view of box 12 in FIG. 5 .
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings and particularly to FIG. 1 herein, a deactivation roller hydraulic valve lifter (DRHVL) 10 , as disclosed in U.S. Pat. No. 6,513,470, includes roller 12 , lifter body 14 , deactivation pin assembly 16 , plunger assembly 18 , pin housing 20 , pushrod seat assembly 22 , spring seat 23 , lost motion spring 24 , and spring tower 26 . As shown, DRHVL 10 is inserted into its respective bore 19 of engine 31 for engagement with the engine camshaft (not shown).
Roller 12 , associated with body 14 of DRHVL 10 , rides on a lobe of the camshaft and translates the rotary motion of the camshaft to vertical motion of lifter body 14 . An anti-rotation guide (not shown in FIG. 1 ) secured to the engine fits around the lifter body to prevent the lifter from rotating during reciprocation. Deactivation pin assembly 16 normally engages lifter body 14 and transfers the vertical reciprocation of lifter body 14 to pin housing 20 . Vertical reciprocation is, in turn, transferred to plunger assembly 18 and pushrod seat assembly 22 . Deactivation pin assembly 16 can be selectively disengaged to decouple lifter body 14 from pin housing 20 and to decouple plunger assembly 18 and pin housing 20 from the vertical reciprocation of lifter body 14 .
Lifter body 14 includes on its outside surface at least one anti-rotation flat 14 a which is aligned with a similar anti-rotation flat on the interior surface of the anti-rotation guide. Alignment of these flats prevent the lifter from rotating within the guide during reciprocation of the lifter.
In the anti-rotation guide disclosed in U.S. Pat. No. 5,088,455, the flats on the outside surface of the lifter body are tight fitting to similar flats on the inside surface of the anti-rotation guide so that the guide can snuggly grip the lifter body as a kitted lifter/guide assembly. The assembly relies on the snug grip to keep the lifter in place and in its proper orientation with the cam lobe during engine assembly. With the anti-rotation guides properly positioning and aligning each lifter as a kit, each lifter can be readily inserted into its respective bore 19 .
Referring now to FIGS. 2 a and 2 b , lifter body 14 is an elongate cylindrical member dimensioned to be received within the space occupied by a standard roller hydraulic valve lifter. Lifter body 14 has central axis A and includes cylindrical wall 32 having an inner surface 34 . Inner surface 34 includes circumferential oil supply recess 34 a . Inner surface 34 of cylindrical wall 32 defines annular pin chamber 42 . Pin chamber 42 is a contiguous chamber of a predetermined axial height which extends around the entire circumference of inner surface 34 of cylindrical wall 32 . Control port 38 is defined by an opening that extends through cylindrical wall 32 , terminating at and opening into annular pin chamber 42 . Pressurized oil is injected through control port 38 into annular pin chamber 42 in order to retract deactivation pin assembly 16 from within annular pin chamber 42 . Oil port 40 passes through cylindrical wall 32 and into oil supply recess 34 a , thereby providing a passageway for supplying the hydraulic lash mechanism with oil, as known in the art.
As best shown in FIG. 1 , deactivation pin assembly 16 includes preferably two pin members 46 , 48 interconnected by and biased radially outward relative to lifter body 14 by pin spring 50 . Each of pin members 46 , 48 are dimensioned to be received within annular pin chamber 42 . A small gap G is provided between stepped flats 46 a , 48 a and the lower edge of annular pin chamber 42 . Gap G provides for clearance between flats 46 a and 48 a and the lower edge of annular pin chamber 42 , thereby allowing for free movement of pin members 46 and 48 into pin chamber 42 . Each of pin members 46 and 48 define pin bores 52 and 54 , respectively. Each of pin bores 52 and 54 receive a corresponding end of pin spring 50 . In its normal or default position, pin members 46 and 48 of deactivation pin assembly 16 are biased radially outward by pin spring 50 such that at least a portion of each pin member 46 and 48 is disposed within annular pin chamber 42 of lifter body 14 .
Referring to pin housing 20 and plunger assembly 18 as shown in FIG. 4 , high pressure chamber 100 is conjunctively defined by bottom inner surface 86 of pin housing 20 , plunger bottom 70 of plunger assembly 18 , and the portion of inner surface 82 of cylindrical side wall 80 of pin housing 20 disposed therebetween. Plunger orifice 74 provides a passageway for the flow of fluid, such as, for example, oil, between high pressure chamber 100 and low pressure chamber 72 . The ball-type check valve formed by plunger ball 62 , plunger spring 64 , and ball retainer 66 selectively controls the ability of the fluid to flow through plunger orifice 74 .
Spring seat 23 , as best shown in FIG. 3 , is a ring-shaped member, having collar 130 , flange 132 , and orifice 134 . Collar 130 is disposed concentrically within lifter body 14 and adjacent to the top edge of side wall 80 ( FIG. 4 ) of pin housing 20 . Flange 132 extends radially from collar 130 such that flange 132 overlaps onto the top edge of cylindrical wall 32 of lifter body 14 . The height of gap G is determined by the dimensions of spring seat 23 . More particularly, the length of the axial extension of collar 130 into lifter body 14 determines the axial position of pin housing 20 relative to lifter body 14 , thereby determining the height of gap G.
Lost motion spring 24 is a coil spring having one end associated with spring seat 23 and the other end associated with spring tower 26 . Lost motion spring 24 has a predetermined installed load which is selected to prevent hydraulic element pump up due to oil pressure in high pressure chamber 100 and due to the force exerted by plunger spring 64 .
Spring tower 26 , as best shown in FIG. 3 , is an elongate cylindrical member having an outer wall 140 . A plurality of slots 142 are defined in outer wall 140 . Tabs 144 are formed along the bottom end of outer wall 140 . A portion of outer wall 140 is concentrically disposed within pin housing 20 , adjacent to inner surface 82 of side wall 80 . Slots 142 enable spring tower 26 to be flexible enough to be pushed downward into pin housing 20 until each of tabs 144 are received within and snap into or engage upper annular groove 108 ( FIG. 4 ) formed in side wall 80 of pin housing 20 . Spring tower 26 defines at its top end tower collar 146 , which is associated with the top end of lost motion spring 24 . The lower end of spring tower 26 , disposed within pin housing 20 , acts to limit the extended height of pushrod seat assembly 22 .
In the deactivated state of DRHVL 10 , as lifter body 14 is vertically displaced by the engine cam lobe, lost motion spring 24 is compressed. As the cam lobe returns to its lowest lift profile, lost motion spring 24 expands and exerts, through spring seat 23 , a downward force on lifter body 14 . Any lift loss that occurs due to leakdown is recovered through the expanding action of plunger spring 64 . Thus, the lash remaining in DRHVL 10 is limited to the gap G which is precisely set through the dimensions of spring seat 23 . Lengthening collar 130 places pin housing 20 axially lower relative to lifter body 14 thereby decreasing the height of gap G. By adjusting the axial dimension of collar 130 , variations in manufacturing tolerances and variations in the dimensions of the component parts of DRHVL 10 can be accurately compensated for while a tight tolerance on gap G is accurately maintained.
Lost motion spring 24 prevents separation between DRHVL 10 and the engine cam lobe in the deactivated or disengaged state. Further, lost motion spring 24 resists the expansion of DRHVL 10 when the cam is at its lowest lift profile position. The tendency of DRHVL 10 to expand is due to the force exerted by plunger spring 64 and oil pressure within high pressure chamber 100 acting upon plunger 60 of assembly 18 . These forces tend to displace pin housing 20 downward toward roller 12 , thereby reducing gap G. Thus, the oil pressure within high pressure chamber 100 and the force exerted by plunger spring 64 will expand, or pump-up, DRHVL 10 by displacing pin housing 20 downward toward roller 12 . Spring tower 26 is firmly engaged with pin housing 20 . Therefore, any downward movement of or force upon pin housing 20 will be transferred to spring tower 26 . Thus, a compressive force, or a force in a direction toward roller 12 , is exerted upon lost motion spring 24 via the downward force or movement of pin housing 20 . The pre-load or installed load of lost motion spring 24 is selected to resist the tendency of DRHVL 10 to pump-up or expand. If expansion is not resisted or limited by the installed load of lost motion spring 24 , gap G will be reduced as pin housing 20 is displaced downward relative to pin chamber 42 , and may adversely affect the ability of locking pin members 46 , 48 to engage within pin chamber 42 .
Referring now to FIG. 5 , a deactivation roller hydraulic valve lifter and anti-rotation guide assembly 205 , including DRHVL 200 and anti-rotation guide 250 of the present invention, is shown. DRHVL 200 has central axis A 1 , and includes roller 212 , lifter body 214 , deactivation pin assembly 216 , plunger assembly 218 , pin housing 220 , pushrod seat assembly 222 , spring seat 223 , lost motion spring 224 , and spring tower 226 .
Anti-rotation guide 250 of the present invention has central axis A 2 , and includes generally cylindrical wall 252 surrounding bore 254 , and keepers 256 . Bore 254 defines a first diameter 258 ( FIG. 11 ) as taken at a diameter orientation non-inclusive of keepers 256 . DRHVL 200 is disposed in bore 254 of anti-rotation guide 250 . Spring seat 223 , in accordance with the invention, includes outer ridge portion 232 and inner ring portion 234 . Inner ring portion 234 is associated with an edge surface of lifter body 214 and pin housing 220 , as shown in FIG. 5 . Spring seat 223 serves both to set gap G as described above, and, via outer ridge portion 232 , to loosely retain DRHVL 200 in guide 250 , as will be described below.
The generally cylindrical outer surface of lifter body 214 defines a second diameter 260 and includes recessed areas or flats 214 a , 214 b , disposed on the end of lifter body 214 opposite roller 212 . First width 262 , measured across keepers 256 engage corresponding flats 214 a , 214 b in lifter body 214 . Second diameter 260 of lifter body 214 is smaller than first diameter 258 of guide 250 . That is, as shown in FIG. 11 , after lifter body 214 is inserted into guide 250 , an annular clearance 264 is formed between second diameter 260 and first diameter 258 .
Second width 266 measured across outer ridge portion 232 of spring seat 223 ( FIG. 5 ) extends slightly beyond a third width 268 of body 214 taken across flats 214 a and 214 b , such as, for example, by approximately 0.25 mm to approximately 0.75 mm.
When assembled as shown in FIG. 5 , DRHVL 200 is inserted from the keeper end of anti-rotation guide 250 and pushed firmly into bore 254 of anti-rotation guide 250 . Since second width 266 measured across outer ridge portion 232 is slightly greater than first width 262 measured across guide keepers 256 , ridge portion 232 deflects keepers 256 until ridge portion 232 is disposed above ledge 270 ( FIG. 12 ) of anti-rotation guide 250 and DRHVL 200 is retained within anti-rotation guide 250 . Thus disposed, the portions of outer ridge portion 232 proximate flats 214 a , 214 b extend beyond the outer surface of lifter body 214 and engages or seats upon ledge 270 , thereby retaining DRHVL 200 within anti-rotation guide 250 as a subassembly, (i.e., kitted), for easy installation within engine 31 . Preferably, leading edge 272 and trailing edge 274 of outer ridge portion 232 are radiused to keep ridge portion 232 from biting into keepers 256 when the lifter is inserted into through bore 254 . Spring seat 223 of DRHVL 200 optionally may include upper lip 223 a around which a first end of lost motion spring 224 is disposed. Upper lip 223 a prevents excessive radial movement of lost motion spring 224 relative to central axis A 1 during operation of DRHVL 200 .
While the present invention in FIG. 5 shows spring seat 223 having a collar portion extending downward toward pin housing 220 , it is understood that seat 223 , does not have to include a collar portion but may be a washer-like, flat member. Moreover, while outer ridge portion 232 is shown as being circular in shape and positioned generally concentric with the lifter body axis, it is understood that ridge portion 232 can be eccentric with the lifter body axis or, rather than being circular in shape, can take the shape of one or more tabs proximate flats 214 a , 214 b , extending beyond lifter body 214 . Finally, while the present invention is shown as part of a deactivation lifter assembly having a spring tower and an external lost motion spring, it is contemplated that ridge portion 232 could be used in conjunction with a deactivation lifter having an internal lost motion spring or in conjunction with a standard (non-deactivation) lifter.
It should be particularly noted that using outer ridge portion 232 to retain DRHVL 200 within anti-rotation guide 250 substantially reduces friction between lifter body 214 and anti-rotation guide 250 relative to conventional methods of retaining lifters within anti-rotation guides. Prior art lifters are retained within anti-rotation guides by a substantial interference or frictional fit between the lifter body and the anti-rotation guide. In contrast, in the present invention DRHVL 200 is inserted into anti-rotation guide 250 until outer ridge portion 232 passes keeper portion 256 and seats on ledge 270 of anti-rotation guide 250 . Minimum clearance 264 (or only a slight interference) between the guide and the lifter body permits free reciprocation of the lifter in the guide during engine operation. Thus, the engagement of ledge 270 by outer ridge portion 232 and not an interfering fit between the lifter body and guide retains DRHVL 200 within anti-rotation guide 250 .
The interface between anti-rotation guide 250 and lifter body 214 imposes substantially no frictional force that counteracts the operation of DRHVL 200 in reciprocating between the valve-closed position ( FIG. 9 a ) and the valve-open position ( FIG. 9 b ), and thus has distinct advantages over the conventional methods of retaining a lifter within an anti-rotation guide as described above. Since the size of the plunger springs used in DRHVLs are limited due to the reduced size of the hydraulic element in such lifters as compared to the size of the hydraulic element in a standard non-deactivation lifter, reducing friction between lifter body 214 and anti-rotation guide 250 enables plunger spring 276 ( FIG. 5 ) to be of a smaller size and of a smaller spring force, while still being of sufficient size/force to provide hydraulic recovery within DRHVL 200 .
Generally, substantial or complete lifter collapse occurs when engine 31 is not operating, and in lifters that are engaged with or stopped upon a lifting portion of the profile of an associated cam lobe. The valve spring (not shown) of engine 31 pushes through pushrod 259 (shown in phantom in FIG. 5 ) and displaces plunger assembly 218 axially downward, i.e., in the direction of roller 212 , within and relative to pin housing 220 which, in turn, compresses plunger spring 276 and causes the high pressure chamber to leak down. When engine 31 is first started, and engine oil pressure is relatively low, the only force available to recover leak down and reestablish engagement of pin housing 220 , lifter body 214 and roller 212 with the cam lobe is the force exerted by plunger spring 276 . Any friction between lifter body 214 and anti-rotation guide 250 may be sufficient to counteract the expansion force exerted by plunger spring 276 , and can result in undesirable lifter noise or clatter, especially when the frictional force approaches the force of plunger spring 276 . Since only ledge 270 is engaged by outer ridge portion 232 to retain lifter body 214 within anti-rotation guide 250 in accordance with the invention, substantially no frictional force exists between lifter body 214 and anti-rotation guide 250 . Thus, the force exerted against lifter body 214 by plunger spring 276 is not substantially counteracted by friction between lifter body 214 and anti-rotation guide 250 . Therefore, substantially all of the force of plunger spring 276 is used to bring pin housing 220 , lifter body 214 and roller 212 into engagement with the cam lobe of the engine camshaft. The adverse effects, i.e., lifter noise or clatter, of the constraints imposed upon the size and force of plunger spring 276 are therefore reduced.
Spring tower 226 of DRHVL 200 includes first portion 226 a and second portion 226 b . First portion 226 a is of a smaller diameter relative to second portion 226 b , and thus spring tower 226 has a stepped outside diameter. The increased diameter of second portion 226 b , relative to the smaller diameter of spring tower 26 of DRHVL 10 and relative to the smaller diameter of first portion 226 a , increases the angle through which pushrod 259 can pivot relative to central axis A 1 without contacting second portion 226 b of spring tower 226 and helps to center the end of the pushrod with the center of socket 219 of pushrod seat assembly 222 . Further, the increased diameter of second portion 226 b enables the use of larger-diameter lost motion spring 224 having an increased spring force, thereby increasing the engine oil pressure limit under which DRHVL 200 is operable.
Second portion 226 b of spring tower 226 also includes opening 225 through which pushrod 259 enters DRHVL 200 for engagement with pushrod seat assembly 222 . A plurality of flutes 282 ( FIG. 5 ) disposed axially about the inner surface of anti-rotation guide 250 serve to centrally guide pushrod 259 toward pushrod seat assembly 222 during engine assembly. Edge surfaces 284 of flutes 282 serve to guide ball end 259 a of pushrod 259 away from tower collar 246 when the pushrod is inserted into DRHVL 200 through guide 250 .
Referring to FIGS. 6 through 8 , guide 250 of the present invention may be conveniently provided in a ganged element 286 wherein a plurality of guides are formed for use with an equal number of lifters. In element 286 , two of the guides 250 are intended for use with DRHVL 200 ; and the other two guides 250 ′ are intended for use with standard, non-deactivating lifters 288 . Thus, the four guides may be conveniently mounted to engine 31 as a unit such as, for example, via a single bolt (not shown) through bolt hole 287 , as known in the art. The four-lifter guide element 286 permits four appropriate lifters to be pre-assembled as a kit 286 ′ and then installed simultaneously into engine 31 .
Referring again specifically to FIGS. 5 , 11 and 12 , guide 250 is provided with two keepers 256 for engaging two flats 214 a , 214 b as described above, to provide sufficient torque to resist rotation of the lifter body in its mating guide during engine operation. Each deactivation lifter 200 has an oil port 238 that must mate with a corresponding control oil passage 31 a in engine 31 , requiring that lifter 200 must be correctly oriented when inserted into its bore 19 in engine 31 ; a single flat 214 a can provide such orientation, but would provide less torque to resist rotation of the lifter body in its mating guide, as compared to the two-flat design. A second and opposing flat can provide added resistance to lifter rotation, but the addition of a second and opposite flat 214 b creates ambiguity. In guide 250 , such ambiguity is resolved by providing an indexing rib 290 ( FIG. 11 ) in one of flats 214 b , and a mating longitudinal groove 291 in one of keepers 256 for engagement with rib 290 . Conversely, rib 290 may be provided in one of flats 214 a , 214 b and grooves 291 may be provided in one of keepers 256 . In the present invention, engagement walls 292 and 293 , of rib 290 and groove 291 , respectively, are formed perpendicular to flats 214 a,b and parallel to each other, to provide greater resistance to rotation of the lifter body in its mating guide.
Referring to FIG. 12 , preferably, the longitudinal edge 294 of keepers 256 is formed in an hourglass shape so that only mid segment 295 of edge 294 is parallel to flats 214 a , 214 b of body 214 . This shape permits outer ridge portion 232 to engage ledge 270 of ant-rotation guide 250 while in kit 286 ′ form prior to engine installation. Yet, after assembly, relief angle α of first segment 296 and relief angle θ of second segment 297 permit some angular deviation of body 214 from centerline A 2 of anti-rotation guide 250 after kit 286 ′ is installed in engine 31 . Preferably, relief angles α and θ are less than 10°. Preferable, the length of mid segment 295 that is parallel with flats 214 a , 214 b is approximately 2.0 mm.
This application is therefore intended to cover any variations, uses, or adaptations of the present invention using the general principles disclosed herein. Further, this application is intended to cover such departures from the present disclosure as come within the known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | An anti-rotation guide for a deactivation hydraulic valve lifter for an internal combustion engine. The guide includes a through bore accommodating of a hydraulic valve lifter and is sized such that the outer end of the lifter may be inserted into the through bore of the guide. The guide is securable to the engine such that the lifter is reciprocable within the guide. The guide is provided with two opposing keepers for mating with corresponding flats on the lifter to prevent rotation of the lifter. Further, a keyway means is provided in the guide and lifter to prevent the lifter being inserted into the guide 180° from the correct orientation. | 5 |
CROSS REFRENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional Patent Application Ser. No. 60/489,664 filed Jul. 24, 2003.
TECHNICAL FIELD OF INVENTION
[0002] The present invention relates to amplifier design, and more particularly to a power amplifier for audio and other signals. Still more specifically, the present invention relates to design of an amplifier circuit capable of manipulating an unregulated AC signal to provide an amplified signal to a load device, so that fluctuations in the power supply to the amplifier circuit are compensated for, and noise or ripples present in the power supply are removed, eliminating the requirement for a regulated power supply.
BACKGROUND OF THE INVENTION
[0003] Power amplifiers are commonly used to amplify electrical signals supplying power to certain types of electronic devices, such as audio speakers. Most power amplifiers use, and depend upon, clean, regulated direct current (DC) power input. Unregulated DC power generated from unregulated alternating current (AC) is “noisy”, containing power fluctuations unsuitable for most power amplifying applications.
[0004] In typical applications, power amplifiers must convert an unregulated, noisy 120-volt AC power source into a regulated, clean DC power source. If the unregulated AC power input is simply rectified to a DC power input, any fluctuations, noise or ripple in the AC power signal may be transferred to the DC power signal. The noise inherent in DC power in this situation may be translated to the amplified output signal. In audio applications, such excessive variances in the power supply will result in undesirable hum, distortions, and noise at the speaker. As such, there is a need for regulated DC power supplies to power applications with a reduced noise factor.
[0005] Conventional power amplifiers rectify an AC signal to a regulated DC power source with transformers and other active inductive and capacitive circuits, which account for the majority of the weight, waste heat output, and cost of production associated with these prior-art amplifiers. As such, there is also a need for audio amplifiers that weigh less, produce less heat, and cost less.
[0006] A number of approaches have been tried to minimize or overcome the above-identified problems. U.S. Pat. No. 4,042,890 to Eckerie filters the DC power signal to reduce high-frequency noise. U.S. Pat. No. 4,605,910 to Covill produces a switch modulated signal for producing an output signal that is independent of the supply voltage, thereby eliminating noise caused by fluctuating AC voltage signals. U.S. Pat. No. 4,737,731 to Swanson senses variations in the DC power signal and adjusts the gain in the audio frequency signal according to the variances to reduce modulation distortion. In U.S. Pat. No. 5,132,637 also to Swanson, a plurality of actuable power amplifiers are controlled by a correction signal to produce a cleaner signal. U.S. Pat. No. 5,777,519 to Simopoulos uses a correction signal as an input to a variable switching power supply to eliminate some noise in the power signal.
[0007] However, each of these methods share the problems of high cost, high heat loss, high weight, and overall inefficiency. A different method for regulating the power output that eliminates the regulated DC power source would offer significant advantages in cost and efficiency as well as a significant reduction in weight and increase in output power.
SUMMARY OF THE INVENTION
[0008] The present invention eliminates the need to regulate a DC power supply by regulating the gain of an amplifier in response to fluctuations and ripple in the unregulated DC power supply so that those fluctuations and ripples do not appear at the output power signal. Unregulated AC power may be supplied from a conventional AC outlet or from an isolation or other transformer. Unregulated AC power is first rectified into unregulated DC power, and this unregulated DC power signal is monitored by a voltage divider to establish a power supply “variance” signal. This variance signal is then squared by an analog multiplier. A second multiplier processes the signal from the first multiplier with a triangular wave signal to produce an input signal to an internal comparator. The first and second voltage multipliers comprise a triangular wave modulator. The resulting output signal from the second multiplier is the modulated triangular wave signal.
[0009] An internal comparator accepts an input audio signal as well as the output signal from the second multiplier. This internal comparator monitors and processes the input audio signal with the modulated triangular wave signal to generate a Pulse Width Modulation (PWM) output signal. From the internal comparator, the PWM output signal is amplified by power device transistors, and the amplified PWM signal passes through filters to remove a high-frequency carrier component. The signal output from the filters is an amplified PWM power signal, which is then used to drive a load device.
[0010] The variances in the power supply voltage are demodulated or removed by this approach, thereby eliminating the need for a regulated DC power supply. The invention provides for dynamic adjustment for noise in the unregulated DC power supply, resulting in a simpler and more efficient power amplifier to derive a clean, regulated, amplified power drive signal. The present invention also provides audio improvements including compression and frequency equalization.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The objects and features of the invention will become more readily understood from the following detailed description and appended claims when read in conjunction with the accompanying drawings in which like numerals represent like elements.
[0012] FIG. 1 is a basic circuit block diagram illustrating a preferred embodiment of the functional components of the power amplifier of the present invention.
[0013] FIG. 2 is a circuit schematic of a preferred embodiment of the AC power circuit.
[0014] FIG. 3 is the circuit schematic of a preferred embodiment of the DC bridge rectifier and voltage divider.
[0015] FIG. 4 is a circuit schematic of a preferred embodiment of the triangular wave modulator (TWM) containing two voltage multipliers.
[0016] FIG. 5 is a circuit schematic of a preferred embodiment of the pulse width modulator (PWM) controller containing the triangular wave generator and pulse width modulation amplifier.
[0017] FIG. 6 is the circuit schematic of a preferred embodiment of the power device transistor and filter.
[0018] FIG. 7 is a circuit schematic of a preferred embodiment of the RMS-to-DC converter used to provide an additional signal for providing dynamic range compression, or Automatic Gain Control, to the amplifier circuit.
[0019] FIG. 8 is a composite circuit schematic of a preferred embodiment of the present invention for a modulated triangular wave audio power amplifier.
[0020] FIG. 9 illustrates the internal operative connectivity for the PWM controller illustrated schematically and described in detail in connection with FIG. 5 .
[0021] FIG. 10 is a block diagram of the modulated triangular wave audio power amplifier configured as a noise-canceling amplifier.
[0022] FIG. 11 is a block diagram of the modulated triangular wave audio power amplifier configured to compress or expand dynamic range or for signal equalization or cancellation.
[0023] FIG. 12 is a block diagram of the modulated triangular wave audio power amplifier configured to introduce an additional signal to output.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] In the following Detailed Description of the Preferred Embodiments, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. For example, intervening electrical components may be located along electrical connections, and electrical components of different ratings may be used, without departing from the scope of the present invention. Moreover, persons of ordinary skill in the art will know that numerous minor alternatives to a specific circuit design are possible, without departing from the scope of the present invention. Thus understood, the details of the circuit provided, including the ratings of the electrical components in the specific preferred embodiments, are not intended to limit the scope of any claim, nor to be read into any claim, but merely to provide an example of a fully enabled and disclosed best mode of practicing a preferred embodiment of the invention.
[0025] FIG. 1 illustrates a preferred embodiment of the basic electrical components of the amplifier of the present invention. As seen in FIG. 1 , an AC power supply 5 is coupled to an optional AC power circuit (transformer) 7 by an electrical connection 50 . Optional AC power circuit 7 is coupled to a bridge rectifier 10 by an electrical connection 51 . Bridge rectifier 10 is coupled to a voltage divider 15 by an electrical connection 55 . Bridge rectifier 10 is also coupled to a power device transistor 30 by an electrical connection 60 .
[0026] Voltage divider 15 is coupled to a first input 21 of a first voltage multiplier 20 by an electrical connection 65 and to a second input 22 by an electrical connection 66 . The output of first voltage multiplier 20 is coupled to a first input 24 of a second voltage multiplier 23 by an electrical connection 67 . A triangular wave generator 27 is coupled to a second input 26 of second voltage multiplier 23 by electrical connection 68 . First voltage multiplier 20 and second voltage multiplier 23 comprise a triangular wave modulator (TWM) 91 .
[0027] The output of second voltage multiplier 23 is coupled to a first input 28 of an internal comparator 25 by an electrical connection 70 . In a preferred embodiment, an audio signal source 35 is coupled to a second input 29 of an internal comparator 25 by an electrical connection 80 . The output of internal comparator 25 is coupled to a power device transistor 30 by an electrical connection 75 . In the preferred embodiment, internal comparator 25 is internal of a pulse width modulation controller integrated circuit (PWM controller 93 ) that includes triangular wave generator 27 , as described in detail below. Power device transistor 30 is coupled to a filter 40 by an electrical connection 85 . Filter 40 is coupled to a load device 45 by an electrical connection 90 .
[0028] In operation, unregulated AC power supply 5 supplies an unregulated, AC power signal to the amplifier. The unregulated AC power signal passes through bridge rectifier 10 , which rectifies, or converts, the unregulated AC power signal into an unregulated DC power signal. This unregulated DC power signal is used to provide a reference voltage to triangle wave modulator 91 as well as being used by power device transistors 30 to power load device 45 .
[0029] From bridge rectifier 10 , the unregulated DC power signal passes through voltage divider 15 . Voltage divider 15 establishes a unity voltage level and provides two input power signals comprising the voltage variance of the power signal into first voltage multiplier 20 . First voltage multiplier 20 multiplies these two signals together, providing an unregulated DC power signal equal to the square of the voltage variance.
[0030] The output of first voltage multiplier 20 is coupled to first input 24 of second voltage multiplier 23 . Triangular wave generator 27 generates a triangular wave signal that is coupled to second input 26 of second voltage multiplier 23 . These two signals are multiplied together by second voltage multiplier 23 to generate a modulated triangular wave signal.
[0031] The modulated triangular wave signal, output from triangular wave modulator 91 , is the first input to PWM Amp 25 . The second input to PWM Amp 25 is the audio signal being amplified, from audio source 35 . PWM Amp 25 compares the modulated triangular wave signal and the audio signal to generate a pulse width modulation (PWM) power signal carrying the audio component. The PWM power signal then passes to power device transistors 30 , which amplify the PWM power signal. This amplified PWM power signal then passes through filter 40 (e.g., an inductance capacitor filter) which filters out the high-frequency carrier component of the PWM power signal. This filtered PWM power signal provides a clean, undistorted audio signal free of noise to load device 45 because the modulated triangle wave signal compensates for variances in AC power supply 5 , powering the load device 45 for the relevant application.
[0032] FIG. 2 illustrates a preferred embodiment for the AC power circuit ( 7 in FIG. 1 ) of the present invention. In this embodiment, the AC power circuit uses a triac 150 and optocoupler 140 to delay the onset of AC power in the amplifier. This time delay power-on circuit delays the onset of AC power to allow the control circuit to stabilize and avoid loud pops when switched on.
[0033] In the circuit, AC power from an outside AC power source (e.g., wall outlet, generator, etc.) is provided through an electrical pole 101 and an electrical pole 103 . Electrical poles 101 and 103 are coupled respectively by an electrical connection 102 and an electrical connection 104 in a parallel electrical circuit with a two-pole circuit breaker 105 . Electrical connection 102 is coupled from circuit breaker 105 to a transformer 110 (e.g., 12-volt transformer). Electrical connection 104 is also coupled from circuit breaker 105 to transformer 110 .
[0034] Transformer 110 steps down the supply voltage (e.g., from 120-volts AC to 12-volts AC). Current flows from transformer 110 through two electrical connections 111 and 113 to a bridge rectifier 112 . The output from bridge rectifier 112 passes through electrical connections 116 and 114 to a filter network 115 . In a specific preferred embodiment, filter network 115 comprises a 2200 μF capacitor 117 , a 100 μF capacitor 118 , and a 1 μF capacitor 119 coupled in parallel with bridge rectifier 112 by electrical connections 116 and 114 .
[0035] An electrical connection 121 couples a power supply regulator 120 to electrical connection 116 . In a specific preferred embodiment, power supply regulator 120 is of the type comparable to a Motorola 78L12. Power supply regulator 120 is coupled to an electrical ground 108 by an electrical connection 123 . A capacitor 124 and a capacitor 126 are coupled to power supply regulator 120 by an electrical connection 122 . The two capacitors 124 and 126 are also coupled together by electrical connection 114 .
[0036] An electrical connection 127 couples a resistor 128 to a terminal V 12 125 . Terminal V 12 125 represents a source of direct current (DC) power supplied for the circuit. In the preferred embodiment disclosed, the voltage supplied is for a 12-volt circuit. Also in the preferred embodiment disclosed, resistor 128 is a 68K-ohm resistor. A resistor 129 is coupled to electrical connection 127 by an electrical connection 130 in a parallel electric circuit configuration.
[0037] As stated, terminal V 12 125 is coupled to electrical connection 127 , and this electric terminal V 12 125 provides a DC power source (e.g., 12-volt). Resistor 128 and resistor 129 are both coupled to the DC power source. Resistor 128 is coupled in series with another resistor 131 by electrical connection 133 . In a specific preferred embodiment, resistor 131 is a 68K-ohm resistor. Resistor 129 is coupled in series with a capacitor 132 by an electrical connection 134 . Resistor 131 is coupled to an electrical ground 108 by an electrical connection 136 , and capacitor 132 is coupled to an electrical ground 108 by an electrical connection 137 .
[0038] A comparator 135 is coupled to electrical connections 133 and 134 . The non-inverting input to comparator 135 is coupled to electrical connection 134 by an electrical connection 139 . The inverting input of comparator 135 is coupled to electrical connection 133 by an electrical connection 141 . Comparator 135 compares the input voltages of the two electrical connections. If the voltage at electrical connection 139 is less than the voltage at electrical connection 141 , the output of comparator 135 will be low, with the voltage at the output at an electrical connection 142 at the lowest possible value (e.g., digital output=0). If the voltage at electrical connection 139 is greater than the voltage at electrical connection 141 , the output of comparator 135 will be high, with the voltage at the output at electrical connection 142 at its highest value (e.g., digital output=1).
[0039] An optocoupler 140 is comprised of a light emitting diode (LED) 171 and a phototransistor 172 inside a component case. Light emitting diode 171 emits light when the digital output value from comparator 135 equals 1 (e.g., the voltage at electrical connection 139 is greater than that at electrical connection 141 ). An electrical connection 143 couples a resistor 144 to the LED 171 . An electrical connection 146 couples resistor 144 to ground 108 . In a specific preferred embodiment, resistor 144 is a 560K-ohm resistor.
[0040] Phototransistor 172 has a light sensitive base region. When light strikes the photosensitive base of phototransistor 172 , the emitter-to-collector resistance falls, allowing current to flow through phototransistor 172 . When the digital output value from comparator 135 equals 1 (logic 1 state), LED 171 is illuminated. Light from LED 171 charges the base of phototransistor 172 , permitting current flow through phototransistor 172 . Thus, optocoupler 140 functions as a switch triggered by the output of comparator 135 .
[0041] An electrical connection 152 couples circuit breaker 105 and the AC power to a capacitor 157 , a triode alternating current switch (triac) 150 , and a resistor 145 . Resistor 145 is coupled to optocoupler 140 by an electrical connection 147 . An electrical connection 149 further couples electrical connection 147 to the gate of triac 150 . Triac 150 is coupled to a terminal L 2 165 and optocoupler 140 by an electrical connection 151 . Capacitor 157 is coupled to a resistor 155 by an electrical connection 156 , and resistor 155 is further coupled to terminal L 2 165 by an electrical connection 153 . Terminal L 1 160 is coupled to transformer 110 and breaker 105 by electrical connection 107 .
[0042] Optocoupler 140 isolates triac 150 from the control circuit. When phototransistor 172 is activated by LED 171 , voltage applied to the gate of triac 150 causes current to flow through triac 150 and energize terminal L 2 165 . Once the gate activates triac 150 , AC power will continue to terminal L 2 165 and L 1 160 as long as the circuit remains energized. The optocoupler 140 and triac 150 combination will delay circuit power-up until the control circuit stabilizes, avoiding pops and hiss from the audio output.
[0043] FIG. 3 illustrates a preferred embodiment of a bridge rectifier 205 ( 10 in FIG. 1 ) and a voltage divider (resistors 210 , 215 , and their electrical interconnection, 15 in FIG. 1 ) of the present invention. A pair of terminals L 1 160 and L 2 165 are coupled to bridge rectifier 205 by electrical connections 201 and 202 respectively. Two electrical output connections from bridge rectifier 205 couple to a resistor-capacitor (RC) filter and resistor voltage divider network arrangement. An electrical connection 208 couples bridge rectifier 205 to terminal V H 240 . Terminal V H 240 represents a high voltage terminal connection. An electrical connection 207 couples bridge rectifier 205 to an electrical connection 221 , and to an electrical connection 206 . Electrical connection 221 is coupled to ground 108 . An electrical connection 209 couples bridge rectifier 205 to a capacitor 230 . In a specific preferred embodiment, capacitor 230 is a 1000 μF capacitor. Electrical connection 206 couples capacitor 230 to electrical connection 207 . Electrical connection 209 is also coupled to electrical connection 208 .
[0044] A resistor 210 and a resistor 215 are connected in series to each other and to capacitor 230 in a parallel circuit. An electrical connection 212 couples resistor 210 to electrical connection 208 . An electrical connection 211 further couples resistor 210 to resistor 215 . Electrical connection 221 couples resistor 215 to ground 108 .
[0045] An electrical connection 213 couples resistors 210 and 215 to the non-inverting terminal of an operational amplifier 218 (op amp 218 ). An electrical connection 217 couples the output of op amp 218 to the inverting terminal input of op amp 218 . Thus configured op amp 218 performs as a voltage follower. An electrical connection 216 connects the output of op amp 218 (the voltage follower) to a terminal T 1 250 . The arrangement of the resistors 210 and 215 and the electrical connections 213 and 211 between resistors 210 and 215 comprises a resistor voltage divider network. One or both of resistors 210 and 215 may be variable, to accommodate adjustment of the power variance signal.
[0046] FIG. 4 illustrates a preferred embodiment of the circuit for the triangular wave modulator ( 91 in FIG. 1 ) of the present invention. Although the preferred embodiment shown in FIG. 4 discloses a design for an analog circuit, the equivalent functionality may be achieved through digital circuitry, such as, for example, by use of digital signal processors.
[0047] As seen in FIG. 4 , a terminal T 1 250 is coupled to a first resistor 382 by an electrical connection 301 . Resistor 382 is subsequently coupled to a first voltage multiplier 310 ( 20 in FIG. 1 ), an integrated circuit chip with a voltage multiplier circuit, by an electrical connection 383 to pin 1 . Terminal T 1 250 is coupled to a second resistor 381 by electrical connection 301 through an electrical connection 303 . Resistor 381 is subsequently coupled to first voltage multiplier 310 by an electrical connection 384 to pin 8 . Pin 7 of voltage multiplier 310 is coupled to a capacitor 305 (typically 0.1 μF) by an electrical connection 308 . Pin 2 of first voltage multiplier 310 is coupled to electrical connection 308 by an electrical connection 309 .
[0048] Capacitor 305 is coupled to ground 108 by an electrical connection 306 . Terminal V G 302 is coupled to electrical connection 308 by an electrical connection 304 . Terminal V G 302 represents a virtual ground for supplying a ground reference to single power supply electrical components. Pin 5 of first voltage multiplier 310 is coupled to a resistor 315 by an electrical connection 312 , and resistor 315 is coupled to a terminal V 12 125 by an electrical connection 314 . In a specific preferred embodiment, resistor 315 is 60K-ohm resistor. Pin 6 of first voltage multiplier 310 is coupled to terminal V G 302 by electrical connection 377 .
[0049] Pin 4 of first voltage multiplier 310 is coupled to the inverting input of an op amp 320 by an electrical connection 311 . A resistor 325 is coupled to the inverting input of op amp 320 by an electrical connection 317 , which is coupled to electrical connection 311 . An electrical connection 321 couples an RMS terminal 330 to the pin 8 input of a second voltage multiplier 340 ( 23 FIG. 1 ) through an electrical connection 336 . An electrical connection 324 couples resistor 325 to the output of op amp 320 through an electrical connection 327 . An electrical connection 326 couples a resistor 335 to electrical connection 324 .
[0050] Electrical connection 336 couples resistor 335 to pin 8 of second voltage multiplier 340 . This signal input is the square of the variance of the input voltage to first voltage multiplier 310 . The signal from RMS terminal 330 is added to this signal. The second input is from a triangular wave generator through pin 1 of second voltage multiplier 340 . Pin 7 of second voltage multiplier 340 is coupled to an electrical connection 351 by electrical connection 341 . Pin 2 of second voltage multiplier 340 is coupled to electrical connection 341 by an electrical connection 343 .
[0051] Pin 5 of second voltage multiplier 340 is coupled to a resistor 355 by an electrical connection 337 . Resistor 355 is further coupled to a terminal V 12 125 by an electrical connection 339 . In a specific preferred embodiment, resistor 355 is a 60K-ohm resistor. Pin 6 of second voltage multiplier 340 is connected to V G 302 by an electrical connection 379 which is coupled to electrical connection 351 .
[0052] Pin 4 of second voltage multiplier 340 is the output of the two voltage multipliers. This output is connected to an inverter amplifier circuit, comprising an op amp 350 and resistor 358 . Pin 4 of second voltage multiplier 340 is coupled to the inverting input of op amp 350 by an electrical connection 344 . Electrical connection 356 couples resistor 358 to electrical connection 344 . The output of op amp 350 is coupled to electrical connection 357 , which couples resistor 358 to capacitor 360 by connection 352 . Capacitor 360 is coupled to terminal T 3 375 by electrical connection 361 .
[0053] Pin 1 of second voltage multiplier 340 receives the input triangular wave signal. Terminal T 2 380 is coupled to a capacitor 365 by electrical connection 366 . In a specific preferred embodiment, capacitor 365 is a 0.047 μF capacitor. Capacitor 365 is coupled to the non-inverting input of a voltage follower op amp 370 by an electrical connection 371 . The output of op amp 370 is coupled to a resistor 345 by an electrical connection 346 . In a specific preferred embodiment, resistor 345 is a 10K-ohm resistor. Electrical connection 346 is coupled to the inverting input of voltage follower op amp 370 by an electrical connection 373 . Resistor 345 is coupled to pin 1 of second voltage multiplier 340 by an electrical connection 342 .
[0054] FIG. 5 illustrates a preferred embodiment of the present invention for the pulse width modulation controller ( 93 in FIG. 1 ) including its audio input circuitry, the triangular wave generator, and the pulse width modulation amplifier. The audio source signal input to the amplifier is through terminals T 4 401 and T 5 402 . Terminal T 4 401 is coupled to a capacitor 412 by an electrical connection 407 . In a specific preferred embodiment, capacitor 412 is a 22 μF capacitor. A resistor 405 is coupled to electrical connection 407 by an electrical connection 408 . In a specific preferred embodiment, resistor 405 is a 100K-ohm resistor. Resistor 405 is coupled to a terminal V G 302 by an electrical connection 409 , and terminal T 5 402 is coupled to electrical connection 409 by an electrical connection 404 .
[0055] Capacitor 412 is coupled to a resistor 415 by an electrical connection 406 . In a specific preferred embodiment, resistor 415 is an 11K-ohm resistor. A capacitor 410 is coupled to electrical connection 406 by an electrical connection 403 . In a specific preferred embodiment, capacitor 410 is a 0.1 μF capacitor 410 . Resistor 415 is coupled to the non-inverting terminal of an op amp 416 by an electrical connection 414 . Capacitor 410 is connected in a parallel circuit to resistor 415 by an electrical connection 411 connected to electrical connection 414 .
[0056] Op amp 416 is configured as a follower. Electrical connection 414 is coupled to the non-inverting input of op amp 416 . The output of the op amp 416 is coupled to a resistor 418 by an electrical connection 413 . In a specific preferred embodiment, resistor 418 is a 390-ohm resistor. An electrical connection 417 couples electrical connection 413 to the inverting input of op amp 416 , thus configuring op amp 416 as a voltage follower. Resistor 418 is coupled to a capacitor 420 by an electrical connection 419 . In a specific preferred embodiment, capacitor 420 is a 22 μF capacitor. Capacitor 420 is coupled to a pulse width modulation controller 430 ( 93 in FIG. 1 ).
[0057] In the preferred embodiment disclosed, PWM controller 430 is an integrated circuit chip, which provides the triangular wave generator and internal comparator circuit. An electrical connection 421 is connected to PIN 1 (AUDA) of PWM controller 430 . A terminal AA 425 is coupled to electrical connection 421 by an electrical connection 426 . Terminal AA 425 represents the audio input to the circuit. In the preferred embodiment, the audio input is buffered as shown by voltage follower 416 . A capacitor 423 is coupled to electrical connection 421 by an electrical connection 422 , and the capacitor 423 is coupled to ground 108 by an electrical connection 427 . In a specific preferred embodiment, capacitor 423 is a 6800-pF capacitor.
[0058] An electrical connection 451 couples the audio input signal to an inverting amplifier 450 . Electrical connection 451 is coupled to a resistor 452 . An electrical connection 449 couples resistor 452 to the inverting input of op amp 450 . An electrical connection 467 couples electrical connection 449 to another resistor 448 . In a specific preferred embodiment, resistor 452 and resistor 448 are 22K-ohm resistors.
[0059] A capacitor 456 is coupled to electrical connection 451 by an electrical connection 477 . Capacitor 456 is coupled to ground 108 by an electrical connection 457 . In a specific preferred embodiment, capacitor 456 is a 47-pF capacitor. A resistor 454 is coupled to electrical connection 477 by an electrical connection 453 , in a parallel circuit arrangement with capacitor 456 . An electrical connection 459 couples resistor 454 to connection 458 , thence to Terminal V G 302 .
[0060] Terminal V G 302 is coupled to electrical connection 459 by an electrical connection 458 . An electrical connection 461 couples electrical connection 459 to the non-inverting input of op amp 450 . A capacitor 462 is coupled to electrical connection 461 by an electrical connection 469 , and electrical connection 493 couples capacitor 462 to electrical connection 495 and ground 108 .
[0061] The output of the op amp 450 is coupled to a resistor 445 by an electrical connection 471 . In a specific preferred embodiment, resistor 445 is a 390-ohm resistor. Resistor 445 is coupled to a capacitor 443 by an electrical connection 444 . In a specific preferred embodiment, capacitor 443 is a 22-μF capacitor. An electrical connection 479 couples capacitor 443 to pin 8 , the Audio B (AUD B) input, on controller 430 . An electrical connection 481 couples electrical connection 479 to a capacitor 440 , and electrical connection 497 couples capacitor 440 to ground 108 . In a specific preferred embodiment, capacitor 440 is a 6800-pF capacitor 6800 .
[0062] In a specific preferred embodiment, pulse width modulation controller 430 is a Zetex ZXCD 1000 , the internal configuration of which is illustrated in FIG. 9 . In this embodiment, electrical connection 421 is coupled to pin 1 of PWM controller 430 . Pin 1 is the Audio A (AUD A) input, which is the non-inverting input to the first internal comparator on controller 430 . The Audio B (AUD B) input, pin 8 , is coupled to op amp 450 by electrical connection 479 . AUD B is the non-inverting input to the second internal comparator on controller 430 . A terminal T 3 375 , the output from second voltage multiplier 340 , is coupled to the Triangle B (TRI B) input, pin 7 , of PWM controller 430 by electrical connection 489 . Electrical connection 429 couples electrical connection 489 , and terminal T 3 375 , to Triangle A (TRI A) input, pin 2 of PWM controller 430 .
[0063] PWM controller 430 includes two internal comparators (see FIG. 9 ). The AUD A input, pin 1 of PWM controller 430 , is coupled to the non-inverting input of the first internal comparator, and the TRI A input, pin 2 of PWM controller 430 , is the inverting input of the first internal comparator. The Output A (OUT A), pin 15 of PWM controller 430 , is the output signal from the first internal comparator and is coupled to terminal T 6 498 by an electrical connection 463 . The AUD B input, pin 8 on PWM controller 430 , is the non-inverting input of the second internal comparator, and the TRI B input, pin 7 of PWM controller 430 , is the inverting input of the second internal comparator. The Output B (OUT B), pin 10 of PWM controller 430 , is the output signal from the second internal comparator and is coupled to terminal T 7 499 by an electrical connection 486 .
[0064] PWM controller 430 also generates the triangular wave signal input to second voltage multiplier 340 . OSC A generates a triangular wave signal. The OSC A output, pin 3 , is coupled to terminal T 2 380 by electrical connection 431 . Referring back to FIG. 4 , it is seen that the triangular wave signal at terminal T 2 380 subsequently passes through capacitor 365 , follower 370 , and resistor 345 , to the pin 1 input of second voltage multiplier 340 . Referring again to FIG. 5 , pin 5 of PWM controller 430 , COSC, is coupled to a capacitor 437 by electrical connection 432 , and capacitor 437 is coupled to ground 108 by electrical connection 439 . In a specific preferred embodiment, capacitor 437 is a 330-μF capacitor. Pin 9 of PWM controller 430 , GND, is coupled to ground 108 by electrical connection 479 . Pin 11 of PWM controller 430 , GND2, is coupled to electrical connection 479 and ground 108 by an electrical connection 496 .
[0065] Pin 12 of PWM controller 430 , 9VB, is connected to an internal power supply of PWM controller 430 (typically 9-volt), and is coupled by an electrical connection 472 to three capacitors 470 , 474 , and 480 , which are individually connected in a bridge, or parallel arrangement to electrical connection 479 . Pin 14 of the PWM controller 430 , 9VA, is connected to the internal power supply of PWM controller 430 (typically 9-volt), and is coupled by an electrical connection 469 to electrical connection 472 and the three capacitors 470 , 474 , and 480 . Pin 16 of the PWM controller 430 , 5V5, is connected to an internal power supply of PWM controller 430 (typically 5.5-volt), and is coupled to a capacitor 435 by an electrical connection 461 . Capacitor 435 is coupled to ground 108 by an electrical connection 443 . An electrical connection 439 couples a capacitor 434 to electrical connection 461 and to 5V5. An electrical connection 441 couples capacitor 434 to ground 108 .
[0066] Pin 13 , V CC , receives the external power supply to PWM controller 430 . Pin 13 , V CC is coupled to the power supply terminal V 12 125 (12-volt in the specific preferred embodiment), by electrical connection 468 , and is coupled by three capacitors 473 , 475 , and 478 in a bridge, or parallel circuit arrangement, to electrical connection 479 and ground 108 . The external power supply V CC supplies power to PWM controller 430 , and regulators on PWM controller 430 drop the power to the internal power sources (typically 9-volt and 5.5-volt) required by the internal circuitry of PWM controller 430 .
[0067] FIG. 6 illustrates a preferred embodiment for the power device transistor and filter ( 30 in FIG. 1 ) of the present invention. A terminal T 6 498 is coupled by an electrical connection 501 to an electrical connection 503 . Electrical connection 503 couples a capacitor 521 to a capacitor 505 in series. An electrical connection 527 couples capacitor 521 to the anode of diode 530 . An electrical connection 529 couples the cathode of diode 530 to a terminal V H 213 . An electrical connection 533 couples a resistor 534 to electrical connection 529 and to the cathode of diode 530 in a parallel circuit. An electrical connection 531 couples electrical connection 527 and an electrical connection 532 to resistor 536 . An electrical connection 535 couples electrical connection 531 to the anode of a diode 537 in a parallel circuit to a resistor 536 . Cathode of diode 537 is coupled to electrical connection 539 by an electrical connection 538 .
[0068] An electrical connection 545 couples a capacitor 546 to electrical connection 529 and terminal V H 213 and the cathode of diode 530 . In a specific preferred embodiment, capacitor 546 is a 0.47-μF capacitor. An electrical connection 548 couples capacitor 546 to ground 108 .
[0069] Electrical connection 539 couples resistor 536 and electrical connection 538 to the gate of a P-channel metal-oxide-semi-conductor field-effect transistor (MOSFET) 540 . The source of MOSFET 540 is coupled to electrical connection 529 by an electrical connection 541 . The drain of MOSFET 540 is connected to an electrical connection 520 by an electrical connection 542 .
[0070] Capacitor 505 is coupled to the cathode of a diode 510 by an electrical connection 504 . An electrical connection 508 couples electrical connection 504 to a resistor 513 . An electrical connection 502 couples electrical connection 508 to a resistor 511 in a parallel circuit to diode 510 . An electrical connection 509 couples resistor 511 to an electrical connection 507 . An electrical connection 512 couples the cathode of a diode 514 to electrical connection 502 in a parallel circuit to resistor 513 . An electrical connection 515 couples the anode of diode 514 to an electrical connection 516 , which is coupled to resistor 513 .
[0071] Electrical connection 516 couples resistor 513 and the anode of diode 514 to the gate of an N-channel MOSFET 517 . The source of MOSFET 517 is coupled to electrical connection 507 by electrical connection 519 , and electrical connection 519 is coupled to electrical connection 548 and ground 108 by electrical connection 507 . The drain of MOSFET 517 is coupled to electrical connection 520 by an electrical connection 518 . Electrical connection 520 is coupled to a inductor 543 . Inductor 543 is coupled to the first output terminal OUT 1 601 of the amplifier by an electrical connection 544 . In a specific preferred embodiment, inductor 543 is a 20-μH inductor. Electrical connection 528 couples a capacitor 547 to electrical connection 520 and inductor 543 . An electrical connection 549 couples capacitor 547 to ground 108 . In a specific preferred embodiment, capacitor 547 is a 1-μF capacitor. The combination of inductor 543 and capacitor 547 forms an LC filter configuration for the signal output at OUT 1 601 .
[0072] A terminal T 9 499 is coupled by an electrical connection 551 to an electrical connection 553 . Electrical connection 553 couples a capacitor 571 and a capacitor 555 together in series. An electrical connection 577 couples capacitor 571 to the anode of a diode 580 . An electrical connection 579 couples the cathode of diode 580 to a terminal V H 214 . An electrical connection 583 couples a resistor 584 to an electrical connection 579 and the cathode of diode 580 in a parallel circuit. An electrical connection 581 also couples electrical connection 577 and an electrical connection 582 to a resistor 586 . An electrical connection 585 couples electrical connection 581 to the anode of a diode 587 in a parallel circuit to resistor 586 . The cathode of diode 587 is coupled to an electrical connection 589 by an electrical connection 588 .
[0073] An electrical connection 595 couples a capacitor 596 to electrical connection 579 and terminal V H 214 and the cathode of diode 580 . In a specific preferred embodiment, capacitor 596 is a 0.47-μF capacitor. Electrical connection 598 couples capacitor 596 to ground 108 .
[0074] An electrical connection 589 couples resistor 586 and an electrical connection 588 to the gate of a P-channel MOSFET 590 . The source of MOSFET 590 is coupled to an electrical connection 579 by an electrical connection 591 . The drain of MOSFET 590 is connected to an electrical connection 570 by an electrical connection 592 .
[0075] Capacitor 555 is coupled to the cathode of a diode 560 by an electrical connection 554 . An electrical connection 558 couples electrical connection 554 to a resistor 563 . An electrical connection 552 couples electrical connection 558 to a resistor 561 in a parallel circuit to diode 560 . An electrical connection 559 couples resistor 561 to an electrical connection 557 . An electrical connection 562 couples the cathode of a diode 564 to electrical connection 552 in a parallel circuit to resistor 563 . An electrical connection 565 couples the anode of diode 564 to an electrical connection 566 , which is coupled to resistor 563 .
[0076] Electrical connection 566 couples resistor 563 and the anode of diode 514 to the gate of an N-channel MOSFET 567 . The source of MOSFET 567 is coupled to electrical connection 557 by an electrical connection 569 , and electrical connection 569 is coupled to an electrical connection 598 and ground 108 by electrical connection 557 . The drain of MOSFET 567 is coupled to electrical connection 570 by an electrical connection 568 . Electrical connection 570 is coupled to an inductor 593 . Inductor 593 is coupled to the second output terminal OUT 2 602 of the amplifier by an electrical connection 594 . In a specific preferred embodiment, inductor 593 is a 20-μH inductor. An electrical connection 578 couples a capacitor 597 to electrical connection 570 and inductor 593 . Electrical connection 599 couples capacitor 597 to ground 108 . In a specific preferred embodiment, capacitor 597 is a 1-μF capacitor. The combination of inductor 593 and capacitor 597 forms an LC filter configuration for the signal output at OUT 2 602 . A load device (not shown), typically a speaker in audio applications, is connected to each of the outputs OUT 1 601 and OUT 2 602 .
[0077] FIG. 7 illustrates an alternative preferred embodiment in which a dynamic range compression component is added to the circuit. In this embodiment, an RMS-to-DC converter integrated circuit 605 (RMS converter 605 ) provides modulation to compensate for volume changes in the input signal (e.g., dynamic range compression). The triangular wave, in addition to being modulated to compensate for power variances, is further modulated with the output of the RMS (root-mean-square) converter 605 . The RMS converter 605 generates a signal relative to the RMS value of the audio input at AA 425 to obtain variable compression of the audio level. In a specific preferred embodiment, RMS converter 605 is an Analog Devices AD 736 RMS-to-DC converter integrated circuit. Pin 1 of RMS converter 605 is coupled to a capacitor 610 by an electrical connection 609 . In a specific preferred embodiment, capacitor 610 is a 10-μF capacitor. Electrical connection 641 couples a terminal V G 302 to capacitor 610 . An electrical connection 608 couples pin 8 of RMS converter 605 to electrical connection 641 and terminal V G 302 . Pin 2 of RMS converter 605 is coupled to terminal AA 425 by an electrical connection 603 and is the input into RMS converter 605 .
[0078] Pin 3 of RMS converter 605 is coupled to a capacitor 625 by an electrical connection 604 . In a specific preferred embodiment, capacitor 625 is a 47-μF capacitor. The output of RMS converter 605 at pin 6 is coupled to a potentiometer 650 by electrical connection 616 . Potentiometer 650 permits selectable, adjustable compression of the triangular wave modulated circuit. The wiper leading from potentiometer 650 is coupled to a resistor 645 . Resistor 645 is coupled to an RMS terminal 330 by an electrical connection 647 . In a specific preferred embodiment, resistor 645 is a 10K-ohm resistor. An electrical connection 652 couples potentiometer 650 to a terminal V G 302 . Electrical connection 616 from the output pin 6 of converter 605 is coupled to capacitor 625 by electrical connection 617 .
[0079] Pin 4 of converter 605 is coupled to an electrical ground 108 by an electrical connection 607 . An electrical connection 613 couples a capacitor 615 to electrical connection 607 . In a specific preferred embodiment, capacitor 615 is a 0.1-μF capacitor. An electrical connection 616 couples capacitor 615 to a terminal V G 302 . An electrical connection 611 couples electrical connection 607 to a capacitor 620 , and electrical connection 612 couples capacitor 620 to pin 5 of the converter 605 . In a specific preferred embodiment, capacitor 620 is a 100-μF capacitor.
[0080] Pin 7 of converter 605 is coupled to a terminal V 12 125 by an electrical connection 618 . An electrical connection 639 couples electrical connection 641 , and terminal V G 302 , to a capacitor 640 . An electrical connection 634 couples capacitor 640 to electrical connection 618 and the terminal V 12 125 . In a specific preferred embodiment, capacitor 640 is a 0.1-μF capacitor.
[0081] FIG. 8 illustrates the connectivity between the various circuit components described in detail hereinabove, showing the relationship between the rectifier and divider circuit of FIG. 3 , the triangle wave modulator of FIG. 4 , the pulse width modulator of FIG. 5 , and the power device of FIG. 6 , as might be implemented in a production circuit board.
[0082] FIG. 9 illustrates the internal operative connectivity for pulse width modulation controller 430 described in the preferred embodiment in detail in connection with FIG. 5 .
[0000] Operation of the Preferred Embodiments
[0083] FIG. 10 illustrates in schematic, block diagram form, the modulated triangular wave amplifier as similarly illustrated in FIG. 1 , according to a preferred embodiment of the present invention. In FIG. 10 , the device is configured as a noise-canceling amplifier, which is capable of removing or canceling “ripple” from a power supply. Power is supplied to rectifier 10 . A signal (such as an audio signal) to be amplified may be provided to an optional pre-amplifier 1011 to boost the signal strength. The amplified signal is then input to PWM controller 93 , while rectified power (DC) is input to TWM 91 .
[0084] A triangle (Δ) wave generated by triangle wave generator 91 ( 27 in FIG. 1 , and described in detail in connection with FIG. 4 ) is coupled from PWM controller 93 and is modulated by TWM 91 and returned to PWM controller 93 . The output of PWM controller 93 is input to power device 30 , which also receives rectified power from rectifier 10 . Thus, the output of PWM controller 93 is employed to cancel noise present in the rectified power signal. The output of power device 30 is typically applied to a filter 40 and then to a load 45 , such as an audio speaker.
[0085] FIG. 11 illustrates in schematic, block diagram form the modulated triangular wave amplifier according to another preferred embodiment of the present invention. In this preferred embodiment, the device is configured to modify the dynamic range of an input signal (i.e., to limit or enhance bandwidth, equalize the signal, or to compensate for, or cancel, signal elements). In this embodiment, power is supplied to rectifier 10 , while a signal (such as an audio signal) to be modified may be provided to an optional pre-amplifier 1011 to boost the signal strength. Rectified power (DC) is input to TWM 91 . The amplified signal is input to a Signal Processor 1013 coupled between the output of pre-amplifier 1011 and TWM 91 . The amplified signal is also input, without signal processing, to PWM controller 93 .
[0086] The choice of signal processor 1013 “type” corresponds with the desired modification to the signal. Thus, the output of PWM controller 93 , with the addition of signal processing through TWM 91 , is used in power device 30 to accomplish the desired modification to the input signal, while power-supply noise-cancellation is also achieved. This configuration is most affectively adapted for audio input signals with an audio speaker load 45 .
[0087] FIG. 12 illustrates in schematic block diagram form, the triangular wave modulated amplifier, according to another preferred embodiment of the present invention. In this preferred embodiment, the device is configured to introduce an overlay or cancellation signal (pink noise, an advertisement, compensation for ambient noise, etc.) onto the output signal to load 45 .
[0088] The overall configuration is identical to that in FIG. 11 , with an additional signal source 1015 supplied to signal processor 1013 . The signal processor 1013 then supplies the processed signal to TWM 91 , which in turn affects the desired modification to the output signal of PWM controller 93 . By this configuration, an overlay or background noise compensation signal may be added while power supply noise-cancellation is also provided.
[0089] In each of the embodiments of the present invention disclosed in FIG. 10 , FIG. 11 , and FIG. 12 , it is understood that unregulated DC power may be supplied directly TWM 91 , if DC power, rather than AC power, is the available power source.
[0090] While the invention has been particularly shown and described with respect to preferred embodiments, it will be readily understood that minor changes in the details of the invention may be made without departing from the spirit of the invention. | The invention is a power amplifier circuit for providing a signal acceptable for use in audio amplifiers or similar applications without requiring a stable power supply free from fluctuation. An alternating current power supply signal rectified to a direct current signal is processed by two voltage multipliers. A voltage divider establishes a unity gain level, and the variance from this voltage is squared by the first voltage multiplier. This squared voltage is then multiplied with a triangular wave signal to generate a modulated triangular wave signal. The modulated triangular wave signal and a signal to be amplified, typically an audio signal, are processed by an internal comparator to generate a pulse width modulated signal. This modulated signal is processed by a power transistor network and filter to provide an amplified signal to a load device. By modulating the triangle wave signal to compensate for fluctuations in the power supply to the amplifier circuit, noise or ripples present in the power supply are demodulated, eliminating the requirement for a regulated power supply. | 7 |
This is continuation of co-pending application Ser. No. 834,086, now abandoned, filed on Feb. 26, 1986.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to motion sensors and, more particularly, to a motion sensor having a movable member that requires no electrical connections.
2. Description of the Prior Art
Motion sensors are commonly used in high precision systems to monitor the linear or rotary movement of an object with respect to another object. For example, position and velocity sensors are commonly used by control systems that control the operation of robots and aircraft tracking systems. Also, position sensors are commonly used with gyroscopes that are employed by aircraft guidance systems.
Several concerns must be addressed when choosing a motion sensor for use in a high precision system. The information produced by the motion sensor should be in a form that is useful to those components of the system that receive it. Systems currently employed commonly use a general purpose computer or a microprocessor to coordinate the flow of information and to process the information. Therefore, it is highly desirable that the motion sensor produce information in digital form. Further, while most physical systems are designed or programmed to operate in a Cartesian coordinate system, many systems, such as robotic systems, operate and sense motion in polar, or other non-Cartesian, coordinate systems. The information produced by the system must be translated to Cartesian coordinates before it can be made useful. That is, the sensor of the system commonly produces an angle output, and the transcendental functions of the angle must be generated to resolve the vector representing the angle into its X-, Y- and Z- components.
Of further concern is the fact that a motion sensor that is employed by certain systems, such as gyroscope systems, should generate as little torque as is possible, since the torque generated by the sensor tends to degrade the performance of the system. A motion sensor can generate reactance torque in two ways. Both types of reactance torque are generated by a device that is commonly called an inductosyn, or a variable transformer sensor. An inductosyn is a mutually coupled magnetic device that employs a stationary member, or stator, and a movable member, or rotor, that is secured to and moved by the object whose motion is to be determined. Each member includes a conductor formed into a number of coils. The surfaces of the members that contain the coils confront each other and one set of coils is energized, thereby inducing an electrical current in the remaining set of coils. As the rotor moves, each coil of the energized conductor moves through positions in which it is located midway between adjacent coils of the nonenergized conductor, and in which the current induced in the nonenergized coils is a minimum, and in which each coil directly confronts a coil of the nonenergized conductor, in which the current provides an indication of the position of the rotor. However, when the coils of each conductor are not completely aligned, there exists a torque on the members that acts in a direction that tends to align the two sets of coils. Frictional torque is also generated by the apparatus of the inductosyn that is required to provide electrical communication between the system and the electrical conductors on the rotor and stator. Therefore, aside from its unsuitablility due to size and weight considerations, the inductosyn is unsuitable for gyroscope applications due to the level of torque it generates. Although inductosyns formed using thin film deposition techniques are smaller and lighter than conventional inductosyns, they still generate an unacceptably high level of torque for many applications requiring a high level of precision. Also, the contacting of the movable member by the current conductor, which is electrically connected to the stationary member of the device, generates undesirable electrical noise in the signal path.
The following United States Patents Nos. disclose motion sensors that either require electrical contact between a moving member and the system that receives information from the sensor, or that have two sets of coils that generate electromagnetic reactive torque as the sensor is operating:
______________________________________2,650,352 2,867,783 3,148,347 3,441,8882,671,892 2,900,612 3,202,948 3,596,2222,685,070 2,915,721 3,281,746 3,758,8452,799,835 2,921,280 3,332,144 3,772,5872,844,802 2,964,721 3,431,525 4,463,333______________________________________
U.S. Pat. No. 3,611,813 shows a tachometer consisting of two circular members, each of which includes a conductor forming an arcuately distorted generally periodic pattern. The conductor on the stator forms two balanced legs of a bridge which produce a zero output signal in the absence of the rotor. When the rotor is rotating proximate the stator, the impedance of the conductors on the stator changes and the rotor modulates the signal produced by the stator. The frequency of modulation increases with the speed of the rotor.
Accordingly, there exists the need for a motion sensor that reduces the amount of electromagnetic and frictional reactance torque that is produced by the sensor, that produces a signal in digital form, and that is particularly well-adapted to include circuitry for providing a signal that is relatively noise free, and that represents a function of the angular position of the rotor with respect to the stator.
SUMMARY OF THE INVENTION
The present invention provides apparatus for providing information pertaining to the position of an object. The apparatus includes a stationary member and a movable member. The stationary member includes a sensing electrical conductor and an active electrical conductor. The active electrical conductor is adapted to receive electrical power. The movable member has at least one element constructed at least partially of magnetic material. The magnetic element electromagnetically couples together the active and sensing conductors to induce an electric current in the sensing conductor when the active conductor receives electrical power. A characteristic of the induced current varies with the position of the movable member relative to the stationary member. Accordingly, the induced current conveys information pertaining to the movement or position of the movable member relative to the stationary member.
Preferably, the stationary member includes two active conductors separated spatially by a sensing conductor. The sensing conductor can include first segments that are closer to a first active conductor and second segments that are closer to the second active conductor. The first and second segments can be disposed alternately on the stationary member. Alternately, the active conductors can be separated spatially by two sensing conductors. The sensing conductors can be so disposed and configured that movement of the movable member induces in the sensing conductors a pair of periodic signals that are separated from each other by 90 electrical degrees.
Accordingly, the present invention provides a motion sensor that reduces the reactance torque it produces, since both the active and sensing conductors are on the same member, and that reduces the amount of frictional torque produced since electrical contact between the movable member of the sensor and the system that uses the sensor need not be made.
BRIEF DESCRIPTION OF THE DRAWINGS
The following detailed description of the preferred embodiments can be understood better if reference is made to the drawings, in which:
FIG. 1 shows the stationary member, or stator, of an angular sensor that can be constructed according to the teachings of the present invention;
FIG. 2 is a plan view of the rotating member, or rotor, of the angular sensor;
FIG. 3 is a side sectional view of a portion of the angular sensor formed by the rotor and stator shown in FIGS. 1 and 2;
FIG. 4 is a graphical representation of the envelope of the electrical signals produced by the stator shown in FIG. 1;
FIG. 5 is a plan view of the stator of an alternate angular sensor that can be constructed according to the teachings of the present invention;
FIG. 6 is a plan view of the rotor of the alternate angular sensor;
FIG. 7 is a side sectional view of a portion of the alternate sensor formed by the rotor and stator shown in FIGS. 5 and 6.
FIG. 8 is a graphical representation of the envelopes of the electrical signals produced by the stator of the alternate angular sensor;
FIG. 9 shows a portion of an alternate embodiment that senses linear motion;
FIG. 10 shows in graphical form the envelopes of the electrical signals produced by a stator when it is used in conjunction with a rotor of the type shown in FIG. 9;
FIG. 11 shows a schematic representation of a linear velocity and acceleration sensor that can be constructed in accordance with the teachings of the present invention; and
FIG. 12 is a side sectional view of the sensor shown in FIG. 11.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 through 3 show the preferred angular motion sensor 10 provided by the present invention. Sensor 10 can provide information pertaining to many motion characteristics, such as position, velocity and acceleration, along with functions, including transcendental, of those characteristics. Generally, sensor 10 includes a stator 12 and a rotor 14. Generally, stator 12 is mounted to a stationary object and rotor 14 is mechanically coupled by any suitable means (such as shaft 13) to the object whose rotary motion is to be monitored. The surfaces of rotor 14 and stator 12 shown in FIGS. 1 and 2 will confront each other with a suitable separation between them. Stator 12 includes a conductor 15 which is arranged on stator 12 to form, generally, multiple concentric transmission rings, for example, rings 16, 18, 20 and 22. It should be noted that electrically, conductor 15 forms transmission lines by placing the conductor on concentric circles and appropriately routing the conductor from one circle to the next to form the pattern shown in FIG. 1. Each concentric circle on which conductor 15 is placed is referred to as a ring. During the operation of sensor 10, conductor 15 receives electrical power from a source external to stator 12. Stator 12 also includes multiple sensing conductors, for example, conductors 24, 26 and 28. It should be noted that only three sensing conductors and four transmission rings are shown in FIG. 1 and discussed herein for the purpose of ease of illustration. The conductors and rings shown in FIG. 1 form only three bits of information, which is unsuitable for many applications of the present invention. For use in most systems, a sensor with more than 20 bits of information is desirable, which would require sensor 10 to have 23 conductors and 24 rings. Clearly, to make such a sensor 10, the diameter of members 12 and 14 should be increased to permit stator 12 to accomodate 23 conductors and 24 rings. Any desired number of bits can be provided by appropriately sizing stator 12 to accommodate a suitable number of conductors and rings.
During operation of sensor 10, rotor 14 induces a current in conductors 24, 26 and 28 from conductor 15. The current in conductors 24, 26 and 28 conveys information pertaining to the motion of rotor 14 relative to stator 12. The signals carried by conductors 24, 26 and 28 are produced at the output of sensor 10 along lines 30, 32 and 34, respectively. As can be seen in FIG. 1, each of conductors 24, 26 and 28 is formed into a square wave configuration. For example, conductor 24 includes first segments 36 that are proximate ring 16 and second segments 38 that are proximate ring 18. Conductor 26 includes first segments 40 that are proximate ring 18 and second segments 42 that are proximate ring 20. Conductor 28 includes first segments 44 that are proximate ring 20 and second segments 46 that are proximate ring 22. Base 48 of stator 12 can be formed from any suitable electrically insulating material. Support 50 of stator 12 similarly can be constructed of any suitable material.
Rotor 14 includes a number of strips 52 that are constructed from magnetic material. Each magnetic strip 52 extends radially from the center of rotor 14 across all seven conductors 16, 18, 20, 22, 24, 26 and 28. Accordingly, each strip 52 magnetically couples conductor 28 to rings 20 and 22, conductor 26 to rings 18 and 20, and conductor 24 to rings 16 and 18. Current is induced in conductors 24, 26 and 28 whenever periodically time-varying or alternating current is flowing through conductor 15.
Each sensing conductor 24, 26 and 28 is adjacent a pair of rings 16, 18, 20 and 22. For example, conductor 24 is adjacent rings 16 and 18. As rotor 14 rotates, each magnetic strip 52 alternately overlies the segments of each conductor 24, 26 and 28. For example, as rotor 14 rotates, each strip 52 alternately overlies outer segments 36 and inner segments 38 of conductor 24. Accordingly, each magnetic strip 52 alternately magnetically couples each conductor 24, 26 and 28 to one of its adjacent rings and to the remaining adjacent ring. Magnetic strips 52 are so arranged on rotor 14 that the position of all strips 52 relative to segments 36, 38, 40, 42, 44 and 46 is the same. Thus, at any given time, all strips 52 completely overlie a segment 36 or 38, or overlie partially both a segment 36 and a segment 38.
As a result, at any one time, a conductor 24, 26 or 28 can be considered to be coupled to its outer adjacent ring, thus having induced in it the signal carried on its outer ring, coupled wholly to its inner adjacent ring, thus carrying an induced current of the type carried by the inner adjacent ring, or, if strips 52 are arranged between segments, a composite signal that consists of a combination of the signals carried on the inner and outer adjacent rings. Therefore, the signals produced by stator 12 on lines 30, 32 and 34 are periodically changing signals each of which alternates between the form of the signal on an outer adjacent ring and the signal on an inner adjacent ring.
The precise form of the output appearing on lines 30, 32 and 34 depends on the form of the signal imposed on conductor 15. Preferably, a high frequency alternating voltage is imposed on line 15. Therefore, each ring 16, 18, 20, and 22 will carry an alternating current that is 180° out of phase with the current carried by each adjacent ring. Each conductor 24, 26 and 28 will be coupled by magnetic strips to one of its adjacent rings, unless magnetic strips 52 are disposed over the transition area between the inner and outer segments of a sensing conductor. If strips 52 are disposed over the outer segments of a conductor, that conductor carries an alternating current of a first phase. If strips 52 are disposed over the inner segments of a conductor, the conductor carries the current induced from the inner ring, which has a phase that is 180° separated from phase of the signal induced by the outer ring. If the strips are over the transition area between the inner and outer segments, the currents induced on the sensing conductor from the inner and outer adjacent rings essentially cancel each other. Therefore, the phase information corresponding to the current carried on a sensing conductor is of binary form and each conductor produces one bit of binary information. By adjusting the diameter of rotor 14 and stator 12 and by adjusting the length of strips 52, sensor 10 can be made to produce binary information of almost any bit length.
Rotation of rotor 14 relative to stator 12 will cause a signal to be imposed on each of lines 30, 32 and 34 that alternates between two signals that are 180° out of phase with each other. When an alternating signal is imposed on line 15 that alternates with a frequency that is high with regard to the frequency of rotation of rotor 14 (for example, from one to 300 kHz), and rotor 14 is rotating at a constant velocity, the waveforms shown in FIG. 4 represent signals which amplitude modulate the high frequency signal imposed on line 15. Stated differently, the waveforms shown in FIG. 4 are the envelopes of the high frequency signals appearing on lines 30, 32 and 34 when rotor 14 rotates at a constant angular velocity.
Any suitable signal processing circuit can be provided for decoding the output of sensor 10. For example, the output of sensor 10 can be applied to a detector that produces the envelope of the output. The envelope, which is, essentially, a binary signal, can be applied to a level detector that decodes the envelope.
Further information pertaining to the position of rotor 14 with respect to stator 12 can be obtained when each strip 52 partially overlies inner and outer segments of a conductor. When a magnetic strip 52 travels from one segment of a conductor to another segment the strip must pass through a transition area where it partially overlies each of the two segments. The transition areas are shown as areas 54 in FIG. 4. Transition areas 54 reflect the fact that when a magnetic strip is travelling from one segment to another, there is a time period during which a conductor 24, 26 or 28 is magnetically coupled to both its inner and outer rings and the current induced on the conductor consists of a contribution from the signal present on each ring. Transition areas 54 can be used to increase the resolution of sensor 10. The level of the envelope of the signal produced by a sensing conductor in the transition area 54 depends on the size of the relative portions of the inner and outer segments overlain by strips 52. Any suitable level translating or slope detecting circuit can be employed to produce a signal representative of the level of the envelope. Accordingly, the position of rotor 14 with respect to stator 12 can be determined "between bits" when strips 52 are between segments of conductors 24, 26 and 28.
Sensor 10 decreases the electromagnetic reactance torque generated by placing both the active and passive conductors on the same member and by reducing the frictional reactance torque by eliminating the need for maintaining electrical communication with rotor 14. Sensor 10 also retains the advantage provided by inductosyns that the output produced by sensor 10 represents the average of the signals produced by a large number of strips 52 in the conductors. Therefore, the effects of any irregularities in manufacturing of rotor 14 and stators 12 of sensor 10 will be minimized.
It will be seen that the configuration of the sensing conductors shown in FIG. 1 permits sensor 10 to provide directly at its output information pertaining to the position of rotor 14 with respect to stator 12. Other motion characteristics along with functions of those characteristics can be provided by proper processing of the output. Alternately, any desired motion characteristic or function of a motion characteristic can be provided by changing the configuration and relative positions of the sensing conductors. For example, the sensing conductors shown in FIG. 1 provide a normal binary numerical sequence as rotor 14 rotates. However, proper arrangement of the convolutions of the sensing conductors would permit sensor 10 to directly produce on lines 30, 32 and 34 the sine of the position of rotor 14 or a grey code, as well as any other desired functions, as rotor 14 rotates.
FIG. 9 shows an alternate construction for the magnetic members of rotor 212. Rotor 212 includes a number of members 100 (only one of which is shown in its entirety in FIG. 9) that are constructed from magnetic material. FIG. 9 further shows sensing conductors 24, 26 and 28 of stator 211 in the proper radial spatial relationship with magnetic members 100. A fourth sensing conductor 222 is shown, which forms the fourth bit shown in FIG. 9. Transmission rings 16, 18, 20 and 22 of stator 12 are also shown in FIG. 9 in proper spatial relationship with sensing conductors 24, 26, 28 and 222. Further, a fifth transmission ring 214 is shown, which, along with transmission ring 16 and sensing conductor 222 forms the fourth and least significant bit shown in FIG. 9. Each magnetic member 100 of rotor 212 defines a number of tiers, four of which are shown in FIG. 9. The number of tiers defined by each magnetic member 100 will depend on the number of bits that stator 211 will be required to produce. Magnetic member 100 should define one tier for each bit of information produced by sensor 200. Strips 102 form tier 203, strips 104 form tier 205, strips 106 form tier 207, and strips 108 form tier 209. Each strip 102 is adapted to couple lines 214 and 16 to sensing conductor 222. Each strip 104 is adapted to couple lines 16 and 18 to sensing conductor 24. Each strip 106 is adapted to couple lines 18 and 20 to sensing conductor 26. Each strip 108 is adapted to couple lines 20 and 22 to sensing conductor 28.
Unlike strips 52 shown in FIG. 1, the width of each strip comprising a magnetic member 100 is adapted to correspond to the width of the sensing conductor segments that the strip is adapted to overlie. The strips 52 shown in FIG. 1 induce in sensing conductors 24, 26 and 28 high frequency signals having the envelope shown in FIG. 4. The waveforms in FIG. 4 have flat peaks 55 and relatively steep transition areas 54, since strips 52 are narrower than the segments formed by sensing conductors 24, 26 and 28. As can be seen from FIG. 10, the envelope of the signals induced in the sensing conductors by the strips of each magnetic member 100 when rotor 212 is moving relative to stator 211 do not have flattened peaks since the width of each strip corresponds to the segment of the sensing conductors corresponding to the strip. Accordingly, the transition areas created by sensor 200 represent a greater proportion of the circumference of sensor 200 than that represented by the transistor areas generated by sensor 10, and more information about the position of rotor 212 "between bits" can be determined than can be determined from sensor 10.
The resolution of sensors 10 and 200 can be adjusted either by changing the number of sensing conductors and transmission rings formed on their stators to adjust the number of bits represented by the outputs of sensors 10 and 200 or by changing the number of segments in each sensing conductor. It should be noted that increasing only the number of segments formed by each sensing conductor increases resolution at the expense of reducing the determinability of sensors 10 and 200. That is, if the number of segments formed by a conductor is greater than 2 n (where n is the number of conductors between the conductor in question and the center of the stator, including the stator in question) the sensor will not produce a unique binary number for each stator position.
It should be noted that any number of known techniques can be used to fabricate sensors 10 and 200. Generally, any known thin film deposition technique used to fabricate integrated circuits would be suitable for fabricating sensors 10 and 200.
FIGS. 5 and 6 show an alternate sensor 60 that can be constructed according to the provisions of the present invention. Sensor 60 includes a stator 62 and a rotor 64. Although sensor 60 could be constructed to provide a unique binary number for each position of rotor 64, sensor 60 is best used to produce signals that can be detected to determine the position of rotor 64. Stator 62 includes a conductor 66 which forms an outer ring 68 and an inner ring 70. An outer passive sensing conductor 72 and an inner passive sensing conductor 74 separate rings 68 and 70. Outer conductor 72 defines short outer segments 76 and long outer segments 78 which are disposed proximate outer ring 68 and short inner segments 80 which are proximate inner ring 70. Inner sensing conductor 74 defines short outer segments 82 which are proximate outer ring 68 and long outer segments 78 of sensor conductor 72. Conductor 74 also defines short inner segments 84 which are proximate inner ring 70 of conductor 66, and long inner segments 86 which are proximate inner ring 70 and short inner segments 80 of outer sensing conductor 72. Stator 62 includes two further conductors 88 and 90 which are arranged on the central portion of stator 62. Each of conductors 88 and 90 forms a coil having two poles. Transmission rings 96 and 98 are separated by conductors 88 and 90 and are energized with a high frequency alternating signal.
Rotor 64 includes two sets of members constructed of magnetic material. Magnetic strips 92 extend radially along the periphery of rotor 64. Two magnetic surfaces 94 are arranged on the central portion of rotor 64 in diametrically opposing positions. Strips 92 are adapted to overlie conductors 66, 72 and 74 and to induce current in conductors 72 and 74 from conductor 66. Surfaces 94 are adapted to overlie and induce current in coils 88 and 90 from rings 96 and 98.
Outer segments 78 of sensing conductor 72 are always coupled by magnetic strips 92 to outer ring 68 of conductor 66. As rotor 64 rotates, each magnetic strip 92 alternately couples a segment 82 to outer ring 68 and a segment 80 to inner ring 70. Long inner segments 86 of conductor 74 are always coupled by magnetic strips 92 to inner ring 70 of conductor 66. As rotor 64 rotates, magnetic strips 92 alternately couple outer segments 82 to ring 68 and inner segments 84 to ring 70 to conductor 66. Accordingly, rotation of rotor 64 modulates high frequency periodic electrical signals causing the envelope shown in FIG. 8 to be induced in sensing conductors 72 and 74. Due to the arrangement of conductors 72 and 74 with respect to each other, the envelopes of the signals induced in conductors 72 and 74 are 90 electrical degrees out of phase with each other.
Any suitable circuit (not shown) can be used to decode the signals represented in FIG. 8. Preferably, however, a zero crossing detector, a threshold detector, and a slope detector are used to decode the signals. The threshold detector is the primary digital decoder. That is, the threshold detector provides the binary number represented by the output of sensor 60. The threshold detector determines when the envelopes produced by sensor 60 are greater than a high threshold and less than a low threshold. The threshold detector assigns a high binary value to the signal when the envelope exceeds the high threshold and a low binary value to the signal when the envelope is less than the low threshold Accordingly, the threshold detector provides a coarse indication of the relation position of rotor 64. The slope detector is an analog circuit that provides a fine determination of the relative position of rotor 64. The slope detector determines the rate of change of the envelope of the signals produced by sensor 60. Thus, the information provided by the slope detector can be used to provide additional information to determine more precisely the position of rotor 64 within the range of positions represented by each binary number produced by the threshold detector. The zero crossing detector is used both as a check on and in conjunction with the slope detector. The zero crossing detector produces an output each time the envelope shown in FIG. 8(a) crosses the zero axis or any desired reference axis. Two sensing conductors are used for each bit of information produced by sensor 60 to produce two envelope inputs to signal processing electronics, and thus increase the precision of sensor 60. As with sensors 10 and 200, and desired number of sensing conductor pairs can be provided to provide information of any desired bit size.
Due to the increased precision per sensing ring or conductor of the information produced by sensor 60 over that produced by sensors 10 and 200, sensor 60 is particularly useful in application where size restrictions prohibit adding the necessary sensing conductors to sensors 10 and 200 to achieve the desired resolution. That is, sensor 60 can provide the same resolution as that provided by sensors 10 and 200, but with fewer bits of information through a combination of digital and analog sensing. However, due to the analog circuitry that must be used with sensor 60 to achieve the desired resolution, sensor 60 will not be as repeatable as sensors 10 and 200.
FIGS. 11 and 12 show an alternate embodiment of the present invention. Sensor 120 is a linear velocity or acceleration sensor. Sensor 120 includes a stationary member 122 and a movable member 124. Stationary member 122 includes an energizing conductor 126 that forms two transmission lines 128 and 130. Stationary member 122 also includes a sensing conductor 132 that forms a number of segments 134 and 136. Movable member 124 is adapted to move in the directions indicated by arrows 138 and 140 and includes a magnetic member 142. Magnetic member 142 defines a number of strips 144 which overlie transmission lines 128 and 130 and portions of conductor 132. As movable member 124 moves with respect to stationary member 122, each magnetic strip 144 alternately couples segments 134 and 136 to transmission line 128 and segments 136. Because sensor 120 senses and provides an indication of only velocity or acceleration, V1 shown in FIG. 11, can be either constant or time varying. If V1 is a constant voltage, movement of member 124 with respect to stationary member 122 will cause pulses of opposite polarity to be induced on sensing conductor 132 and a series of pulses will be produced at V2. If V1 is an alternating signal, that is, a carrier signal, a carrier signal will be produced at V2 that has an envelope generally of the form shown in FIG. 10. Regardless of the form of V1, V2 can be converted to a series of pulses using conventional circuitry and the pulses can be input to a frequency pulse modulator to provide information pertaining to the acceleration and speed of movable member 124. Of course, linear analogs to sensors 10, 60 and 200 can be easily produced by making suitable modifications to sensor 120.
Suitable circuits can be provided to sense and determine the variation in inductance created by the movable members of sensors 10, 60, 120 and 200 to determine position. | A motion and position sensor includes a stationary member having active conductors that carry energizing power and sensing conductors that are electromagnetically coupled by a movable member to generate signals in the sensing conductors that are representative of the position of the movable member. The movable member is contactless and therefore requires no electrical connection to any other component. Thus, frictional reactance torque and electromagnetically generated torque are reduced to a minimum. | 6 |
This application is a continuation-in-part of applicants' copending application Ser. No. 693,463, filed June 7, 1976, now abandoned.
BACKGROUND OF THE INVENTION
Block copolymers have been developed rapidly within the recent past, the starting monomers usually being monoalkenyl arenes such as styrene or alpha-methylstyrene and conjugated dienes such as butadiene and isoprene. A typical block copolymer of this type is represented by the structure polystyrene-polybutadiene-polystyrene (SBS). When the monoalkenyl arene blocks comprise less than about 55% by weight of the block copolymer, the product is essentially elastomeric. Moreover, due to its peculiar set of physical properties, it can be referred to more properly as a thermoplastic elastomer. By this is meant a polymer which in the melt state is processable in ordinary thermoplastic processing equipment but in the solid state behaves like a chemically vulcanized rubber without chemical vulcanization having been affected. Polymers of this type are highly useful in that the vulcanization step is eliminated and, contrary to vulcanized scrap rubbers, the scrap from the processing of thermoplastic elastomers can be recycled for further use.
Those block polymers which comprise in part conjugated diene polymer blocks have at least one substantial shortcoming, namely, their susceptibility to oxidation or ozonolysis. Substantial improvement both in stability and compatibility with alpha-olefin polymers have been made by hydrogenation of such block polymers. The hydrogenation may be non-selective, selective or complete. Certain technical advantages have been found for selective hydrogenation wherein at least about 80% of the aliphatic double bonds are reduced and no more than about 25% of the aromatic double bonds are reduced by hydrogenation. Block copolymers having selectively hydrogenated conjugated diene blocks are disclosed in U.S. Pat. No. 3,595,942.
Correspondingly, a group of polymers commonly referred to as engineering thermoplastics possess a balance of properties comprising strength, stiffness, impact resistance, and long term dimensional stability that make them useful as structural materials. However, for a particular application, the engineering thermoplastic alone may not offer the combination of properties desired and, therefore, means to correct this deficiency are of interest.
One particularly appealing route to achieve a material with the desired combination of properties is through blending together two or more polymers which individually have the properties sought. This approach has been successful in limited cases such as in the improvement of impact resistance for plastic, e.g. polystyrene, polypropylene, poly(vinyl chloride), etc., using special blending procedures or additives for this purpose. However, in general, blending of polymers has not been a successful route to enable one to combine into a single material the desirable individual characteristics of two or more polymers. Instead, it is often found that such blending results in combining the worst features of each with the result being a material of such poor properties as not to be of any practical or commercial value. The reasons for this failure are rather well understood and stem in part from the fact that thermodynamics teaches that most combinations of polymer pairs are not miscible, although a number of notable exceptions are known. More importantly, most polymers adhere poorly to one another. As a result, interfaces between component domains (a result of their immiscibility) represent areas of severe weakness in blends and, therefore, provide natural flaws and cracks which result in facile mechanical failure. Because of this, most polymer pairs are said to be "incompatible". In some instances the term compatibility is used synonymously with miscibility, however, compatibility is used here in a more general way that describes the ability to combine two polymers together for beneficial results and may or may not connote miscibility.
The present invention covers a polymer blend that is stable even though the individual polymers are dissimilar in chemical structure and are expected to be highly incompatible. For example, the styrene blocks of the present block copolymer have a solubility parameter, in units of (cal/cm 3 ) 1/2 as calculated by Small's method (J. Applied Chemistry, Vol. 3, page 71, 1953) of 9.1 and, the poly(ethylene/butylene) block is 7.9. However, the solubility parameter for polyesters such as poly(ethylene terephthalate) is 10.7 while that for cellulose acetate is over 13. See Polymer Handbook, pages IV-341 to 368, Interscience Publishers, 1966. One would not expect to be able to prepare stable blends of two polymers having such different solubility parameters.
SUMMARY OF THE INVENTION
A novel composition has now been found that exhibits excellent dimensional stability and integrity. The composition broadly comprises the admixture obtained by intimately mixing about 4 to about 96 parts by weight of a block copolymer and about 96 to about 4 parts by weight of a thermoplastic polyester so as to form at least partial continuous interlocking networks wherein: (a) said block copolymer comprises at least two monoalkenyl arene polymer end blocks A and at least one substantially completely hydrogenated conjugated diene mid block B, said block copolymer having an 8 to 55 percent by weight monoalkenyl arene polymer block content, each polymer block A having an average molecular weight of between about 5,000 and about 125,000, and each polymer block B having an average molecular weight of between about 10,000 and about 300,000; and (b) said thermoplastic polyester has a generally crystalline structure and a melting point over about 120° C.
The block copolymer of the instant invention effectively acts as a mechanical or structural stabilizer which interlocks the polymer structure networks and prevents the consequent separation of the polymers during processing and their subsequent use. As defined more fully hereinafter, the resulting structure of the instant polyblend (short for ∓polymer blend") is that of two at least partial continuous interlocking networks. This interlocked structure results in a dimensionally stable polyblend that will not delaminate upon extrusion and subsequent use.
To produce stable blends it is necessary that both polymers have at least partial continuous networks which interlock with each other. In an ideal situation both polymers would have complete continuous networks which interlock with each other. A partial continuous network means that a portion of the polymer has a continuous network phase while the other portion has a disperse phase structure. Preferably, a major proportion (greater than 50% by weight) of the partial continuous network is continuous.
It is particularly surprising that stable blends are produced over very wide relative concentrations. For example, blends containing as little as 4 parts by weight of the block copolymer per 100 total in the blend or as high as 96 per 100 total are attainable. As explained more fully hereinafter, the instant block copolymers have this ability to produce stable blends over a wide range of concentrations since they are oxidatively stable, possess essentially an infinite viscosity at zero shear rate, and retain network or domain structure in the melt.
Most significantly, polymer blends of the instant invention have an unexpectedly superior balance of properties. Since each phase network is continuous in every phase, each network can donate independently to the blend properties and it is possible for additive relationships to exist in mechanical phenomena. For example, with regard to modulus related properties: at low volume fraction of the engineering resin, the elastic modulus, modulus temperature behavior, and hardness are characteristic of a foamed resin structure with a density equivalent to the situation where the rubber volume is replaced by air. Another indication of the dominance of the resin skeletal system at low strain is the observation that in the binary system there is normally less than 5 points, and frequently less than two points, difference in Shore A hardness between blends of resin to elastomer of 1:1 and 3:1.
Since each component in the present blends can independently donate to the blend properties within certain boundaries, it is now possible to tailor blends to remove specific defects. For example, DuPont's HYTREL® resin is a polyester-polyether segmented copolymer. However, there is a strong interaction between the polyester and polyether segments in HYTREL® which results in a significant reduction in the polyester melting temperature. On the other hand, blends of poly(butylene terephthalate) and the present block copolymer holds it integrity up to the melting point of the polyester and has better high temperature and related properties. Structural integrity means that without being stretched beyond its elastic limit, the polymer blend will retain its structure and be useful over a wide range of temperatures. One means to measure structural integrity is by a rheovibron analysis. A rheovibron analysis of the subject block copolymer alone shows a sharp drop in modulus at about 100° C corresponding to the glass transition temperature of the styrene end blocks. A similar analysis of the polyester alone slows a sharp drop in modulus at 225° C. One would typically expect a blend of the block copolymer and polyester to have a significant drop off in modulus at 100° C and then again at 225° C. However, a rheovibron analysis of the block copolymer/polyester blend of Illustrative Embodiment I showed that the modulus retained very high values up to about 225° C, thereby revealing an unexpectedly high structural integrity.
In addition, the blends of the present invention approach more nearly the theoretical upper limits of the Tayakangi model for co-continuous versus parallel structures. One would typically expect that the blend of a rubber and an engineering thermoplastic would approach more nearly the theoretical lower limit of the Tayakangi model.
DETAILED DESCRIPTION OF THE INVENTION
A. Block Copolymer
The block copolymers employed in the present invention may have a variety of geometrical structures, since the invention does not depend on any specific geometrical structure, but rather upon the chemical constitution of each of the polymer blocks. Thus, the structures may be linear, radial or branched so long as each copolymer has at least two polymer end blocks A and at least one polymer mid block B as defined above. Methods for the preparation of such polymers are known in the art. Particular reference will be made to the use of lithium based catalysts and especially lithium-alkyls for the preparation of the precursor polymers (polymers before hydrogenation). U.S. Pat. No. 3,595,942 not only describes some of the polymers of the instant invention but also describes suitable methods for their hydrogenation. The structure of the polymers is determined by their methods of polymerization. For example, linear polymers result by sequential introduction of the desired monomers into the reaction vessel when using such initiators as lithium-alkyls or dilithiostilbene and the like, or by coupling a two segment block copolymer with a difunctional coupling agent. Branched structures, on the other hand, may be obtained by the use of suitable coupling agents having a functionality with respect to the precursor polymers of three or more. Coupling may be effected with multifunctional coupling agents such as dihaloalkanes or -alkenes and divinyl benzene as well as certain polar compounds such as silicon halides, siloxanes or esters of monohydric alcohols with carboxylic acids. The presence of any coupling residues in the polymer may be ignored for an adequate description of the polymers forming a part of the compositions of this invention. Likewise, in the generic sense, the specific structures also may be ignored. The invention applies especially to the use of selectively hydrogenated polymers having the configuration before hydrogenation of the following typical species:
polystyrene-polybutadiene-polystyrene (SBS)
polystyrene-polyisoprene-polystyrene (SIS)
poly(alpha-methylstyrene)-polybutadiene-poly(alpha-methylstyrene) and
poly(alpha-methylstyrene)-polyisoprene-poly(alpha-methystyrene)
It will be understood that both blocks A and B may be either homopolymer or random copolymer blocks as long as each block predominates in at least one class of the monomers characterizing the blocks and as long as the A blocks individually predominate in monoalkenyl arenes and the B blocks individually predominate in dienes. The term "monoalkenyl arene" will be taken to include especially styrene and its analogs and homologs including alpha-methylstyrene and ring-substituted styrenes, particularly ring-methylated styrenes. The preferred monoalkenyl arenes are styrene and alpha-methylstyrene, and styrene is particularly preferred. The blocks B may comprise homopolymers of butadiene or isoprene and copolymers of one of these two dienes with a monoalkenyl arene as long as the blocks B predominate in conjugated diene units. When the monomer employed is butadiene, it is preferred that between about 35 and about 55 mol percent of the condensed butadiene units in the butadiene polymer block have 1,2 configuration. Thus, when such a block is hydrogenated, the resulting product is, or resembles, a regular copolymer block of ethylene and butene-1 (EB). If the conjugated diene employed is isoprene, the resulting hydrogenated product is or resembles a regular copolymer block of ethylene and propylene (EP).
Hydrogenation of the precursor block copolymers is preferably effected by use of a catalyst comprising the reaction products of an aluminum alkyl compound with nickel or cobalt carboxylates or alkoxides under such conditions as to substantially completely hydrogenate at least 80% of the aliphatic double bonds while hydrogenating no more than about 25% of the alkenyl arene aromatic double bonds. Preferred block copolymers are those where at least 99% of the aliphatic double bonds are hydrogenated while less than 5% of the aromatic double bonds are hydrogenated.
The average molecular weights of the individual blocks may vary within certain limits. In most instances, the monoalkenyl arene blocks will have number average molecular weights in the order of 5,000-125,000, preferably 7,000-60,000 while the conjugated diene blocks either before or after hydrogenation will have average molecular weights in the order of 10,000-300,000, preferably 30,000-150,000. The total average molecular weight of the block copolymer is typically in the order of 25,000 to about 350,000, preferably from about 35,000 to about 300,000. These molecular weights are most accurately determined by tritium counting methods or osmotic pressure measurements.
The proportion of the monoalkenyl arene blocks should be between about 8 and 55% by weight of the block copolymer, preferably between about 10 and 30% by weight.
While the average molecular weight of the individual blocks is not critical, at least within the above specified limits, it is important to select the type and total molecular weight of the block copolymer in order to ensure the compatibility necessary to get the interlocking network under the chosen blending conditions. As discussed more fully hereinafter, best results are obtained when the viscosity of the block copolymer and the engineering thermoplastic resin are substantially the same at the temperature used for blending and processing. In some instances, matching of the viscosity of the block copolymer portion and the resin portion are best achieved by using two or more block copolymers or resins. For example, a blend of two block copolymers having different molecular weights or a blend of a hydrogenated SBS and hydrogenated SIS polymers may be employed.
Matching of the viscosity of the block copolymer portion and the engineering thermoplastic resin portion may also be accomplished by adding supplemental blending components such as hydrocarbon oils and other resins. These supplementary components may be blended with the block copolymer portion or the engineering thermoplastic resin portion, but it is preferred to add the additional components to the block copolymer portion. This pre-blended block copolymer composition is then intimately mixed with the engineering thermoplastic resin to form compositions according to the present invention.
The types of oils useful in the practice of this invention are those polymer extending oils ordinarily used in the processing of rubber and plastics, e.g. rubber compounding oils. Especially preferred are the types of oil that are compatible with the elastomeric segment of the block copolymer. While oils of higher aromatics content are satisfactory, those petroleum-based white oils having low volatility and less than 50% aromatics content as determined by the clay gel method of tentative ASTM method D 2007 are particularly preferred. The oils should additionally have low volatility, preferably having an initial boiling point above 500° F. The amount of oil employed varies from about 0 to about 100 phr (parts by weight per hundred parts by weight rubber, or block copolymer as in this case), preferably about 5 to about 30 phr.
The additional resins employed in matching viscosities are flow promoting resins such as alpha-methylstyrene resins, and end block plasticizing resins. Suitable end block plasticizing resins include coumarone-indene resins, vinyl toluene-alpha-methylstyrene copolymers, polyindene resins, and low molecular weight polystyrene resins. See U.S. Pat. No. 3,917,607. The amount of additional resin employed varies from about 0 to about 100 phr, preferably about 5 to about 25 phr.
B. Thermoplastic Polyesters
The thermoplastic polyesters employed in the instant invention have a generally crystalline structure, a melting point over about 120° C, and are thermoplastic as opposed to thermosetting.
One particularly useful group of polyesters are those thermoplastic polyesters prepared by condensing a dicarboxylic acid or the lower alkyl ester, acid halide, or anhydride derivatives thereof with a glycol, according to methods well-known in the art.
Among the aromatic and aliphatic dicarboxylic acids suitable for preparing polyesters useful in the present invention are oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, p-carboxyphenoacetic acid, p,p'-dicarboxydiphenyl, p,p'-dicarboxydiphenylsulfone, p-carboxyphenoxyacetic acid, p-carboxyphenoxypropionic acid, p-carboxyphenoxybutyric acid, p-carboxyphenoxyvaleric acid, p-carboxyphenoxyhexanoic acid, p,p'-dicarboxydiphenylmethane, p,p-dicarboxydiphenylpropane, p,p'-dicarboxydiphenyloctane, 3-alkyl-4-(β-carboxyethoxy)-benzoic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, and the like. Mixtures of dicarboxylic acids can also be employed. Terephthalic acid is particularly preferred.
The glycols suitable for preparing the polyesters useful in the present invention include straight chain alkylene glycols of 2 to 12 carbon atoms such as ethylene glycol, 1,3-propylene glycol, 1,6-hexylene glycol, 1,10-decamethylene glycol, 1,12-dodecamethylene glycol and the like. Aromatic glycols can be substituted in whole or in part. Suitable aromatic dihydroxy compounds include p-xylylene glycol, pyrocatechol, resorcinol, hydroquinone, or alkyl-substituted derivatives of these compounds. Another suitable glycol is 1,4-cyclohexane dimethanol. Much preferred glycols are the straight chain alkylene glycols having 2 to 4 carbon atoms.
A preferred group of polyesters are poly(ethylene terephthalate), poly(propylene terephthalate), and poly(butylene terephthalate). A much preferred polyester is poly(butylene terephthalate). Poly(butylene terephthalate), a crystalline copolymer, may be formed by the polycondensation of 1,4-butanediol and dimethylterephthalate or terephthalic acid, and has the generalized formula: ##STR1## where n varies from 70 to 140. The molecular weight of the poly(butylene terephthalate) typically varies from about 20,000 to about 25,000. A suitable process for manufacturing the polymer is disclosed in British Pat. No. 1,305,130.
Commercially available poly(butylene terephthalate) is available from General Electric under the tradename VALOX® thermoplastic polyester. Other commercial polymers include CELANEX® from Celenese, TENITE® from Eastman Kodak, and VITUF® from Goodyear Chemical.
Another useful polyester is polypivalolactone. Polypivalolactone is a linear polymer having recurring ester structural units mainly of the formula:
--CH.sub.2 --C(CH.sub.3).sub.2 C(O)O--
i.e., units derived from pivalolactone. Preferably the polyester is a pivalolactone homopolymer. Also included, however, are the copolymers of pivalolactone with not more than 50 mole percent, preferably not more than 10 mole percent of other beta-propiolactones, such as beta-propiolactone, alpha, alpha-diethyl-beta-propiolactone and alpha-methyl-alpha-ethyl-beta-propiolactone. The term "beta-propiolactones" refers to beta-propiolactone(2-oxetanone) and to derivatives thereof which carry no substituents at the beta-carbon atom of the lactone ring. Preferred beta-propiolactones are those containing a tertiary or quaternary carbon atom in the alpha position relative to the carbonyl group. Especially preferred are the alpha, alpha-dialkylbeta-propiolactones wherein each of the alkyl groups independently has from one to four carbon atoms. Examples of useful monomers are:
alpha-ethyl-alpha-methyl-beta-propiolactone,
alpha-methyl-alpha-isopropyl-beta-propiolactone,
alpha-ethyl-alpha-n-butyl-beta-propiolactone,
alpha-chloromethyl-alpha-methyl-beta-propiolactone,
alpha, alpha-bis(chloromethyl)-beta-propiolactone, and
alpha, alpha-dimethl-beta-propiolactone(pivalolactone).
See generally U.S. Pat. Nos. 3,259,607; 3,299,171; and 3,579,489. These polypivalolactones have a molecular weight in excess of 20,000 and a melting point in excess of 120° C.
Another useful polyester is polycaprolactone. Typical poly(ε-caprolactones) are substantially linear polymers in which the repeating unit is ##STR2## These polymers have similar properties to the polypivalolactones and may be prepared by a similar polymerization mechanism. See generally U.S. Pat. No. 3,259,607.
C. Viscosity Modifiers
In order to better match the viscosity characteristics of the thermoplastic engineering resin and the block copolymer, it is sometimes useful to first blend the thermoplastic engineering resin with a viscosity modifier before blending the resulting mixture with the block copolymer. Suitable viscosity modifiers should have a relatively high viscosity, a melt temperature of over about 230° C, and possess a viscosity that is not very sensitive to changes in temperature. Examples of suitable viscosity modifiers include poly(2,6-dimethyl-1,4-phenylene)oxide and blends of poly(2,6-diemthyl-1,4-phenylene)oxide with polystyrene.
The poly(phenylene oxides) included as possible viscosity modifiers may be presented by the following formula ##STR3## wherein R 1 is a monovalent substituent selected from the group consisting of hydrogen, hydrocarbon radicals free of a tertiary alpha-carbon atom, halohydrocarbon radicals having at least two carbon atoms between the halogen atom and phenol nucleus and being free of a tertiary alpha-carbon atom, hydrocarbonoxy radicals free of aliphatic, tertiary alpha-carbon atoms, and halohydrocarbonoxy radicals having at least two carbon atoms between the halogen atom and phenol nucleus and being free of an aliphatic, tertiary alpha-carbon atom; R' 1 is the same as R 1 and may additionally be a halogen; m is an integer equal to at least 50, e.g. from 50 to 800 and preferably 150 to 300. Included among these preferred polymers are polymers having a molecular weight in the range of between 6,000 and 100,000 preferably about 40,000. Preferably, the poly(phenylene oxide) is poly(2,6-dimethyl-1,4-phenylene)oxide. These poly(phenylene oxides) are described, for example, in U.S. Pat. Nos. 3,306,874; 3,306,875; and 3,639,508.
Commercially, the poly(phenylene oxide) is available as a blend with styrene resin. See U.S. Pat. Nos. 3,383,435 and 3,663,654. These blends typically comprise between about 25 and 50% by weight polystyrene units, and are available from General Electric Company under the tradename NORYL® thermoplastic resin. The preferred molecular weight when employing a poly(phenylene oxide)/polystyrene blend is between about 10,000 and about 50,000, preferably around 30,000.
The amount of viscosity modifier employed depends primarily upon the difference between the viscosities of the block copolymer and the engineering thermoplastic resin at the processing temperature Tp. Typical amounts range from about 0 to about 100 parts by weight viscosity modifier per 100 parts by weight engineering thermoplastic resin, preferably from about 10 to about 50 parts by weight per 100 parts engineering thermoplastic resin.
D. Method of Forming Interlocking Networks
It is an essential aspect of the present invention that the various polymers can be blended in such a way as to form co-continuous interlocking networks; i.e., where a continuous phase of one polymer would be thought of as filling the voids of a continuous phase of the second polymer. The interlocking structure of the various polymers does not show gross phase separation such as would lead to delamination. Further, the blend is not so intimately mixed that there is molecular mixing or miscibility, nor one in which the separate phases will lead to delamination.
Without wishing to be bound to any particular theory, it is considered that there are two general requirements for the formation of an interlocking network. First, there must be a primary phase network stable to the shearing field. This requirement is fulfilled by employing the block copolymers of the instant invention having the capability of self-crosslinking (network formation) and furthermore having sufficiently high molecular weight to retain its network (domain) structure in processing. Second, the other polymers employed must be capable of some kind of chemical or physical crosslinks or other intermolecular association to maintain a continuous phase in the blend. The polymer must possess sufficient fluidity to interlock with the primary network in the blending process. This second requirement is met by the instant thermoplastic engineering resins and the blends of these resins with the instant viscosity modifiers.
There are at least two methods (other than the absence of delamination) by which the presence of an interlocking network can be shown. In one method, an interlocking network is shown when molded or extruded objects made from the blends of this invention are placed in a refluxing solvent that quantitatively dissolves away the block copolymer and other soluble components, and the remaining polymer structure (comprising the thermoplastic engineering resin) still has the shape and continuity of the molded or extruded object and is intact structurally without any crumbling or delamination, and the refluxing solvent carries no insoluble particulate matter. If these criteria are fulfilled, then both the unextracted and extracted phases are interlocking and continuous. The unextracted phase must be continuous because it is geometrically and mechanically intact. The extracted phase must have been continuous before extraction, since quantitative extraction of a dispersed phase from an insoluble matrix is highly unlikely. Finally, interlocking networks must be present in order to have simultaneous continuous phases. Also, confirmation of the continuity of the unextracted phase may be confirmed by microscopic examination.
In the second method, a mechanical property such as tensile modulus is measured and compared with that expected from an assumed system where each continuous isotropically distributed phase contributes a fraction of the mechanical response, proportional to its compositional fraction by volume. Correspondence of the two values indicates presence of the interlocking network, whereas, if the interlocking network is not present, the measured value is different than that of the predicted value.
An important aspect of the present invention is that the relative proportions of the various polymers in the blend can be varied over a wide range. The relative proportions of the polymers are presented below in parts by weight (the total blend comprising 100 parts):
______________________________________ Preferred Most Preferred______________________________________Engineering Thermoplastic 96 to 4 93 to 7Block Copolymer 4 to 96 7 to 93______________________________________
Accordingly, it is possible to prepare a wide variety of polymer blends ranging from a flexibilized engineering thermoplastic to a stiffened elastomeric block copolymer. Note that the minimum amount of block copolymer necessary to achieve these blends may vary with the particular engineering thermoplastic.
The blending of the engineering thermoplastic resin and the block copolymer may be done in any manner that produces a blend which will not delaminate on processing, i.e., in any manner that produces the interlocking network. For example, the resin and block copolymer may be dissolved in a solvent common for all and coagulated by admixing in a solvent in which none of the polymers are soluble. But more preferably, a particularly useful procedure is to intimately mix the polymers in the form of granules and/or powder in a high shear mixer. "Intimately mixing" means to mix the polymers with sufficient mechanical shear and thermal energy to ensure that interlocking of the various networks is achieved. Intimate mixing is typically achieved by employing high shear extrusion compounding machines such as twin screw compounding extruders and thermoplastic extruders having at least a 20:1 L/D ratio and a compression ratio of 3 or 4:1.
The mixing or processing temperature (Tp) is selected in accordance with the particular polymers to be blended. For example, when melt blending the polymers instead of solution blending, it will be necessary to select a processing temperature above the melting point of the highest melting point polymer. In addition, as explained more fully hereinafter, the processing temperature may also be chosen so as to permit the isoviscous mixing of the polymers. Typically, the mixing or processing temperature is between about 150° C and about 400° C. For blends containing poly(butylene terephthalate) Tp is preferably between about 230° C and about 300° C.
Another parameter that is important in melt blending to ensure the formation of interlocking networks is matching the viscosities of the block copolymer and the engineering thermoplastic resin (isoviscous mixing) at the temperature and shear stress of the mixing process. The better the interdispersion of the engineering resin in the block copolymer network, the better the chance for formation of co-continuous interlocking networks on subsequent cooling. Therefore, it has been found that when the block copolymer has a viscosity η poise at temperature Tp and shear rate of 100 sec -1 , it is much preferred that the viscosity of the engineering thermoplastic resin or blend containing such resin have a viscosity at temperature Tp and a shear rate of 100 sec -1 such that the ratio of the viscosity of the block copolymer over the viscosity of the engineering thermoplastic be between about 0.2 and about 4.0, preferably between about 0.8 and about 1.2. Accordingly, as used herein, isoviscous mixing means that the viscosity of the block copolymer divided by the viscosity of the other polymer or polymer blend at the temperature Tp is between about 0.2 and about 4.0. It should also be noted that within an extruder, there is a wide distribution of shear rates. Therefore, isoviscous mixing can occur even though the viscosity curves of two polymers differ at some of the shear rates.
The block copolymer or block copolymer blend may be selected to essentially match the viscosity of the engineering resin. Optionally, the block copolymer may be mixed with a rubber compounding oil or supplemental resin as described hereinbefore to change the viscosity characteristics of the block copolymer.
The particular physical properties of the instant block copolymers are important in forming co-continuous interlocking networks. Specifically, the most preferred block copolymers of the instant invention when unblended do not melt in the ordinary sense with increasing temperature, since the viscosity of these polymers is highly non-Newtonian and tends to increase without limit as zero shear stress is approached. Further, the viscosity of these block copolymers is also relatively insensitive to temperature. This rheological behavior and inherent thermal stability of the block copolymer enhances its ability to retain its network (domain) structure in the melt so that when the various blends are made, interlocking and continuous networks are formed.
The viscosity behavior of the instant thermoplastic engineering resin, on the other hand, typically is more sensitive to temperature than that of the instant block copolymers. Accordingly, it is often possible to select a processing temperature Tp at which the viscosities of the block copolymer and engineering resin fall within the required range necessary to form interlocking networks. Optionally, a viscosity modifier, as hereinabove described, may first be blended with the engineering thermoplastic resin to achieve the necessary viscosity matching.
E. Uses and Additional Components
The polymer blends of the instant invention may be compounded further with other polymers, oils, fillers, reinforcements, antioxidants, stabilizers, fire retardants, antiblocking agents and other rubber and plastic compounding ingredients without departing from the scope of this invention.
Examples of various fillers that can be employed are in the 1971-1972 Modern Plastics Encyclopedia, pages 240-247. Reinforcements are also very useful in the present polymer blends. A reinforcement may be defined simply as the material that is added to a resinous matrix to improve the strength of the polymer. Most of these reinforcing materials are inorganic or organic products of high molecular weight. Various examples include glass fibers, asbestos, boron fibers, carbon and graphite fibers, whiskers, quartz and silica fibers, ceramic fibers, metal fibers, natural organic fibers, and synthetic organic fibers. Especially preferred are reinforced polymer blends of the instant invention containing about 2 to about 80 percent by weight glass fibers, based on the total weight of the resulting reinforced blend. It is particularly desired that coupling agents, such as various silanes, be employed in the preparation of the reinforced blends.
The polymer blends of the instant invention can be employed in any use typically performed by engineering thermoplastics, such as metal replacements and those areas where high performance is necessary.
To illustrate the instant invention, the following illustrative embodiments are given. It is to be understood, however, that the embodiments are given for the purpose of illustration only and the invention is not to be regarded as limited to any of the specific materials or conditions used in the specific embodiments.
Illustrative Embodiment I
In Illustrative Embodiment I, poly(butylene terephthalate) ("PBT") was blended with a particular block copolymer to form co-continuous interlocking network phases. The block copolymer prior to hydrogenation was a styrene-butadiene-styrene block copolymer having a molecular weight distribution of 25,000-100,000-25,000 and a 1,2 content for the butadiene blocks of about 42%. The block copolymer was selectively hydrogenated such that greater than 95% of the aliphatic double bonds were reduced while less than 5% of the aromatic bonds were reduced. This polymer is designated Block Copolymer I (SEBS).
Two different recipes were examined:
______________________________________ (A) (B)______________________________________Block Copolymer I 100 100Engineering Resin 100 70Oil I 100 --Oil II -- 50______________________________________
All units are parts by weight. Oil I is Shellflex 790, a paraffinic rubber extending oil. Oil II is Tufflo 6056, a hydrogenated bright stock oil. Also present is 10 parts polypropylene, 0.2 parts Irganox 1010 (an antioxidant), 0.5 parts dilaurothiodipropionate, LTDP (an antioxidant), and 5 parts TiO 2 . The PBT was General Electric's Valox® 310 resin. The various blends were mixed by passing the components through two passes of a Brabender extruder at 260° C. The viscosity of the components at 260° C were:
______________________________________Block Copolymer plus oil 3,200 poiseand polypropylenePBT 3,000 poise______________________________________
The results are presented below:
______________________________________Blend No. 1 2Recipe No. A BTest ResultsHardness (Shore A) 85 85Tensile at break (psi) Normal 900 1050Parallel 700 1150Elongation at break (%) Normal 220 350Parallel 140 160100% Modulus (psi) Normal 660 800Parallel 880 1100______________________________________
Illustrative Embodiment II
Illustrative Embodiment II discloses blends of two different block copolymers with the PBT to form co-continuous interlocking network phases. Block Copolymer II prior to hydrogenation, was an SBS block copolymer having a molecular weight distribution of about 29,000-116,000-29,000 and a 1,2 content for the butadiene portion of about 42%. Block Copolymer III prior to hydrogenation, was an SBS block copolymer having a molecular weight distribution of about 10,000-55,000-10,000 and a 1,2 content for the butadiene portion of about 42%. Both block copolymers were selectively hydrogenated such that greater than about 95% of the aliphatic double bonds were reduced while less than 5% of the aromatic bonds were reduced. The polypropylene employed was Shell PP 5520. The blend composition is presented below in parts by weight:
______________________________________Blend No. 3Block Copolymer II 60Block Copolymer III 40Oil II 30Polypropylene 15PBT 60Irganox 1010 3.0Plastinox LTDP 0.5Irganox 1024 0.2Total 208.7______________________________________
The blend was prepared by first mixing the block copolymers, oil, polypropylene and additives on a rubber compounding mixer. Then the resulting block copolymer composition was intimately mixed with the engineering thermoplastic resin by passing the components through a WP twin-screw extruding machine at temperature settings between about 240° to 300° C so as to maintain a melt temperature of about 285° to 290° C. The test results are presented below:
______________________________________Physical Properties______________________________________Specific Gravity 0.97Shore A Hardness 87Flexural Stiffness.sup.1 - psi 850100% Modulus - psi 900300% Modulus - psi 1325500% Modulus - psi 1950Tensile at Break - psi 2300Elongation at Break - % 550Tear Strength.sup.2 - pli 315Limiting Oxygen Index 17.7______________________________________ .sup.1 Wire coating from 15 ga 30 mil wall stiffness and tensile properties. .sup.2 Injection molded slabs, flow direction.
Illustrative Embodiment III
In Illustrative Embodiment III various blends of PBT with selectively hydrogenated block copolymers of the present invention were prepared by mixing the polymers in a 11/4 inch Sterling Extruder having a Kenics nozzle. The extruder had a 24:1 L/D ratio and a 3.8:1 compression ratio screw. These block copolymers all had the structure S-EB-S and had block molecular weights as follows:
______________________________________Block Copolymer II 29,000-116,000-29,000Block Copolymer III 10,000-55,000-10,000Block Copolymer IV 7,500-38,000-7,500______________________________________
Where oil was employed, the block copolymer and oil were premixed prior to the addition of the PBT.
The compositions, conditions and test results are presented below in Table 1. In each case, the resulting polyblend had the desired interlocking network phases as established by the criteria hereinabove described.
The small strain properties were obtained by use of an Instron Tensile Tester with a loading rate of 0.2 inches per minute and a strain at 23° C of 0.0333 sec -1 .
TABLE 1__________________________________________________________________________Blend No. 133 137 138 139 144 185 186Compositions,parts by weightBlock Copolymer II 17.5 52.5 35.0Block Copolymer III 7.5 22.5 15.0Block Copolymer IV 13.5 22.7 64.3 72.8Oil 1.5 2.3 6.3 7.2PBT 85.0 75.0 29.4 20.0 75.0 25.0 50.0Mixing Temperature(° C) 294 304 280PropertiesTensile at Break,psi,Normal 3830 3340 3030Parallel 3780 2040 2980100% Modulus, psiNormal 670Parallel 700300% Modulus, psiNormal 1370Parallel 1530Elongation at Break,Normal 30 590 80Parallel 30 410 55Hardness (Shore A) 97.5 78 97.0Small Strain PropertiesTangent (Young's)Modulus, psiNormal 90,900 4,000 100,000Perpendicular 83,300 3,650 87,900__________________________________________________________________________
Illustrative Embodiment IV
In Illustrative Embodiment IV, the polymer blend numbered 144 from Illustrative Embodiment III was examined by a selective extraction technique. In this technique, the polymer blend is subjected to a 16-hour Soxhlet extraction with hot refluxing toluene. Ideally, the hot toluene should extract the block copolymer but should not dissolve the PBT. The unextracted portion of the blend is weighed after extraction and the weight loss compared with the expected values.
The selective extraction technique reveals the presence of co-continuous interlocking networks in blend 144. The toluene extracted 21.4% by weight compared to an expected 25%, well within the accuracy of the technique. This indicates that the block copolymer was continuous since apparently all of the block copolymer was accessible to the hot toluene. The PBT was continuous since no particles became dislodged in the extraction, and the unextracted portion retained its shape.
Comparative Example I
In Comparative Example I an unhydrogenated styrene-butadiene block copolymer having styrene end blocks of about 10,000 molecular weight and a total molecular weight of around 75,000 was blended with PBT according to the procedure of Illustrative Embodiment III. The blend contained about 40% block copolymer and 60% PBT. This blend, however, was successful since the block copolymer began to degrade and crosslink at the temperatures required to melt blend with the PBT. | Polymeric blends having structural integrity at unobviously high temperature and an improved balance of properties are prepared by intimately mixing certain selectively hydrogenated block copolymers with certain thermoplastic saturated polyesters under conditions where at least partial continuous networks which interlock are formed. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to yarn texturing machines, and in particular to textile machines for the texturing of yarns by means of fluid jets.
2. Discussion of the Background
Textile machines are known in which one or more yarns are fed in single, parallel or core/effect form to a fluid jet in which the turbulent fluid serves to cause the filaments of the yarns to form loops, thereby producing a bulky single or composite yarn suitable for various textile applications. To facilitate this process a yarn wetting device may be located immediately upstream of the fluid jet, acting on some or all of the yarns, and in such cases the yarn wetting device and the fluid jet are customarily housed in a common housing or "jet-box". With parallel and, more especially, core/effect arrangements, in order to ensure acceptable texturing of the yarn, it is necessary that any yarn which runs through the wetting device is kept apart from the other yarn or yarns until they come together in the fluid jet itself. If this is not done, entanglement of the filaments of the yarns can take place upstream of the fluid jet, and this prevents or inhibits the texturing of the yarn. To prevent such prior entanglement it is usual to have guides for the two yarns at the entry of the jet-box and also on the body of the jet itself. These guides, whilst keeping the paths of the yarns separate, also provide changes in direction of travel of the yarns, with consequential increases in yarn tension as a yarn travels around a guide. Hence the yarn tensions prior to entry to the jet box may be considerably less than those at entry to the jet itself. Since the tensioning effect of the fluid jet is reduced as the yarn throughput speed increases an upper limit of yarn throughput speed occurs when the yarn tensions upstream of the jet box input guides fall to a level at which threadline instability occurs. To avoid such a problem it is known to feed the two yarns in spaced but converging straight yarn paths from the feed means to the air jet, for example in U.S. Pat. No. 4608814. Such an arrangement eliminates the change in yarn tension along the yarn path. In this prior patent the angular separation of the yarns is specified as being preferably in the range of 8° to 25°. However, at current high processing speeds the yarn tensions upstream of the air jet are low and it has been found that the abovementioned entanglement of the yarns can occur with such an arrangement. It has also been found that too large an angular separation of the converging yarns leads to deterioration in the quality of the resulting textured yarn.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a yarn texturing machine which avoids, at least to a substantial extent, the abovementioned disadvantages, and which ensures adequate control of the yarn throughout its passage through the machine.
The invention provides a yarn texturing machine comprising a fluid jet texturing means for a plurality of yarns to form a textured yarn and respective feed means for each of said yarns, whereby each of said feed means is disposed in said machine relative to the other feed means and said fluid jet texturing means so as to feed the respective yarn along a substantially straight yarn path from said feed means to said fluid jet texturing means, which yarn path is spaced from the path of the other yarn or yarns but converges therewith within said fluid jet texturing means at an angle of between 70° and 50° with respect to each other. Said paths may converge at an angle of substantially 65°. The plane containing said yarn paths may be inclined to the axis of said jet at an angle of between 60° and 90°, preferably at substantially 70°.
Each of said feed means may comprise a pair of feed rollers providing a nip therebetween through which the respective yarn may travel. One roller of each of said pairs of feed rollers may be rotatably driven. For each of said yarns said machine may comprise respective first feed means operable to forward said yarn to said respective feed means at a speed less than that at which said yarn is fed to said fluid jet texturing means, whereby said yarn is drawn between said first feed means and said respective, drawing, feed means. Each of said first feed means may comprise a pair of first feed rollers providing a nip therebetween through which the respective yarn may travel. One roller of each of said pairs of first feed rollers may be driven in rotation.
Heating means for each of said yarns may be provided between the respective first feed means and the respective drawing feed means, and said heating means may comprise a plate, pin or roller. A common heating means may be provided for said plurality of yarns, and said heating means may be electrical heating means or may be vapor phase heating means.
Said machine may comprise a creel, whereby said first feed means are operable to withdraw said yarns from respective supplies thereof mounted in said creel. Said machine may comprise a main frame spaced from said creel and on which said fluid jet texturing means, said drawing feed means and said first feed means are mounted, said first feed means withdrawing said yarns from said supplies thereof along feed paths extending above an operator's aisle disposed between said creel and said main frame.
The machine may also comprise yarn wetting means which may be disposed adjacent but upstream of said fluid jet texturing means. Said wetting means may comprise means adapted to apply water to at least one of said yarns, in which case said wetting means may be disposed so as to apply water to a yarn forming a core yarn of said textured yarn.
Said machine may comprise wind-up means, which may be mounted in said main frame beneath said fluid jet texturing means. Said feed means and said wind up means may be driven by respective drive shafts extending longitudinally of said machine. Said machine may also comprise further treatment means, such as heating means, which may comprise an elongate contact heater mounted on said main frame above said fluid jet texturing means to extend upwardly therefrom. Said further treatment heating means may also comprise turnround yarn guide means around which said textured yarn may pass between an upwards and a downwards passage over said heating means. Said turnround guide means may be mounted on said further treatment heater to be movable longitudinally thereof between a threading location at the lower end of said further treatment heater and an operating location at the upper end of said further treatment heater. Said turnround guide means may be mounted on a sledge. Said further treatment heating means may comprise a heater plate having a pair of substantially parallel grooves therein extending from said lower end to said upper end of said heater.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be further described with reference to the accompanying drawings in which:
FIG. 1 is a threadline diagram of a machine in accordance with the invention
FIG. 2 is a sectional view of part of the machine of FIG. 1 to an enlarged scale, and
FIG. 3 is a front view of the part of the machine of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the figures, there is shown in FIG. 1 a yarn texturing machine 10 comprising a main frame 11 and a creel 12 which are separated from each other by an operator's aisle 13. In the creel 12 are supplies 14 of two yarns 15, 16 (e.g., core and effect yarns). The yarns 15, 16 are withdrawn from their supply bobbins 14 by their respective first feed means 17, 18 which are mounted on the main frame 11 on respective drive shafts 40, 41 so that the yarns 15, 16 in travelling from the creel 12 to the first feed means 17, 18 pass above the operator's aisle 13. Also mounted on the main frame 11 on respective drive shafts 42, 43 are drawing feed means 19, 20 operative to feed the yarn 15, 16 respectively to a texturing section 21. Each of the feed means 17, 18, 19, 20 comprises a driven roller driven by the respective drive shaft 40, 41, 42, 43 and a freely rotatable roller forming a nip therewith through which the yarn 15 or 16 passes. The driven rollers of feed means 19, 20 are driven so as to have a greater peripheral speed than the driven rollers of the first feed means 17, 18 whereby the yarns 15, 16 are drawn between the two sets of feed means 17, 18, 19, 20. To facilitate such drawing a draw pin or roller 22 is mounted on the main frame 11 between the first feed means 17, 18 and the drawing feed means 19, 20. In the case of polyamide yarns being processed, the draw pin or roller 22 may be unheated, but in the case of yarns of polyester, polypropylene, polyvinyl, or the like being processed, the draw pin or roller 22 may be heated. Such heating may be by any known means such as electrical heating or vapor phase heating.
The texturing section 21 is shown in greater detail in FIGS. 2 and 3, and comprises a "box" or housing 23 which is mounted on the main frame 11 and in which is mounted a fluid jet 24 such as an air jet. The relative disposition of the drawing feed means 19, 20 and the fluid jet 24 is such that the yarns 15, 16 are fed from the former to the latter along spaced respective, substantially straight paths, which converge with each other within the fluid jet 24, the plane of the yarn paths being inclined to the axis A of the fluid jet 24 at an angle β of between 60° and 90°, preferably substantially 70°, as shown in FIG. 3. Preferably the yarn paths converge at an angle α of between 70° and 50°, for example substantially 65°, as shown in FIG. 2, thereby ensuring optimum control of the yarns in this low tension region and good quality of textured yarn at completion of texturing. Between the drawing feed rollers 19, 20 and the fluid jet 24 is wetting means 25. The wetting means 25 is preferably of the type described in U.S. Pat. No. 4,719,771 which applies liquid to the core or wetted yarn 15, without it deviating substantially from a straight yarn path from the drawing feed means 20 to the fluid jet 24. In this particular case water from a supply 26 thereof is fed to a manifold 27 and then to the applicator head 28. The wetted yarn 15, and the yarn 16 are fed into the fluid jet 24, to which air or other fluid from a supply 29 thereof is also fed. In the fluid jet 24 the yarns 15, 16 are textured and combined to form a single textured yarn 30 which issues from the fluid jet 24 and is guided through a guide: 31, upwardly out of the box or housing 23. Third feed means 32 driven by drive shaft 44 forwards the textured yarn 30 from the fluid jet 24 to a further treatment or setting heater 33 which extends upwardly above the texturing section 21. The third feed means 32 also comprises a roller driven by drive shaft 44 and a freely rotatable roller forming a nip therewith through which the yarn 30 may pass. The driven roller of the of the third feed means 32 may be driven so as to have a peripheral speed less than that of the driven rollers of the drawing feed means 19, 20 so that the yarns 15, 16 are overfed into the texturing section 21 if desired. The textured yarn 30 passes around a "turnround" guide 34 mounted on a sledge 35 which is itself mounted on the heater 33 so as to be movable longitudinally thereof between a threading position at the lower end of heater 33 (shown in dashed lines in FIG. 2) and an operating position at the upper end of the heater 33 (shown in full lines in FIGS. 1 and 2). With the sledge 35 in the operation position, the yarn 30 makes an upward and then a downward passage over the further treatment heater 33, passing in contact therewith along a groove 37 on its upward journey and groove 38 on its downward journey. The grooves 37, 38 are substantially parallel and extend from the lower end of the heater plate 39 of heater 33 to the upper end thereof. From the lower end of heater 33, the yarn 30 is fed downwardly by fourth feed means 45 to wind up means 36 mounted on the main frame 11 in three rows, one above the other beneath the texturing section 21. The fourth feed means 45 and the wind-up means 36 are driven by respective drive shafts 46, 47 extending longitudinally of the machine 10.
Other embodiments of the texturing machine in accordance with the invention will be readily apparent to persons skilled in the art. For example wetting means 25 for both yarns may be provided and the wetting means 25 may be disposed outside of the housing 23. However, it is preferred that the housing 23 is provided around the fluid jet 24 to contain spray issuing therefrom due to the action of the fluid jet on the wet yarn. Also, if preferred, the textured yarn 30 may be drawn from the housing 23 in a downward direction to a further treatment heater 33 disposed in the main frame 11 beneath the texturing section 21 and behind the wind-up means 36, although such an arrangement may limit the length of the heater 33 and therefore the amount of further treatment received by the yarn 30. The provision of separate first feed means and drawing feed means for the two yarns 15, 16 enables different draw ratios to be applied to the two yarns and different feed rates to the texturing section 21. As an alternative to the embodiment shown, separate draw pins or rollers 22 may be provided if desired, particularly if the drawing temperature for the two yarns is to be different. However as a further alternative the yarns 15, 16 may pass around differing diameter parts of the same feed roller for the purpose of providing differing feed speeds and/or draw ratios. Also the relative position of the fluid jet 24 and the drawing feed means 19, 20 may be adjustable so as to vary the angle of convergence of the two yarns 15, 16 if desired. Any one or each of the feed means 17, 18, 19, 20, 32, 45 may be replaced by a roller / apron, double apron or capstan feed device if desired, each driven by a respective drive shaft extending longitudinally of the machine and common to the appropriate feed means of all the yarn processing stations. The further treatment heaters 33 for each yarn processing station, shown separately in FIG. 3, may be connected as part of a multi-station heater, for example by means of an elongate boiler extending longitudinally of the machine 10 of a vapor phase heater.
In order that the yarn contacting parts of the jet have a usefully long working life whilst being subjected to the abrading action of the yarn, the jet 24, or at least such yarn contacting parts thereof, are of a ceramic material. The use of such a material enables the yarns 15, 16 to enter the jet 24 under tension at the angle of between 60° and 90° to the axis A of the jet 24 without undue wear on the entry part of the jet 24. | A yarn texturing machine having an air jet for combining and texturing at least two yarns to form a single textured yarn, which includes respective yarn feed and drawing devices for each yarn. To provide good control of the yarns in the low tension region upstream of the jet the drawing devices are positioned relative to the jet and each other so that the yarns travelling to the jet travel along straight, spaced yarn paths which converge at the jet at an angle of between 70° and 50°, and lie in a plane inclined at between 60° and 90° to the axis of the jet. After the jet the textured yarn is passed upwardly then downwardly over a setting heater located above the jet and then to a wind-up mechanism disposed beneath the jet. | 3 |
TECHNICAL FIELD
[0001] The present invention relates to garment treatment compositions suitable for domestic use in a laundering process, and in particular to compositions which contain components which can cross-link with cellulose.
BACKGROUND OF THE INVENTION
[0002] Cellulose is a beta 1-4 linked polysaccharide and the principal component of cotton, which is a well-known material for the production of fabrics and in very widespread use. Cellulose is capable of cross-linking by hydrogen bonds which form between the cellulose chains.
[0003] The majority of garments purchased world-wide contain at least some cellulose fibres in the form of cotton or rayon and these suffer from the well-known problem that on exposure to water, such as during domestic laundering, fibre dimensions change and cause shrinking, shape change and wrinkling of the garments. It is believed that this is due to release and reformation of hydrogen bonds.
[0004] So-called ‘durable press’ treatments of fabrics are intended to overcome these difficulties. One of the most common methods of durable pressing uses a crosslinking agent to immobilise cellulose at a molecular level. Known cross-linking agents for whole cloth include formaldehyde, and urea-glyoxal resins. Other proposals include epichlorohydrins, vinyl sulphones, acrylo-amide and acrylo-acrylates. None of these proposed technologies have demonstrated any commercial viability for domestic on finished garments use to date.
[0005] A range of industrial processes for use in the manufacture of finished fabrics are known.
[0006] U.S. Pat. No. 4,588,761 discloses poly-urethane coating compositions for use with a transfer paper or other temporary support. These comprise an isocyanate which is preferably blocked. This is an industrial treatment process for fabric and is inherently unsuitable for use at home on finished garments.
[0007] JP 53035098 discloses a finishing process for treating woven or knitted cellulosic fabrics with a processing solution comprising a urethane prepolymer with blocked terminal isocyanate groups, a gloxal-amide type cross-linking agent and a bromo-fluorinated metal. The process is not suitable for domestic application to finished garments.
[0008] JP6346374 discloses finishing of fabric or a sewed product by a stepwise industrial process comprising treatment with a blocked isocyanate, heat treatment and subsequent use of a gas phase cross-linking agent. A similar process is disclosed in JP8127972.
[0009] JP 55093882 discloses a method for flocked fabric production which uses masked isocyanate. JP 9316781 discloses a finishing agent for use in the production of yarn, paper or films which comprises a blocked isocyanate. JP 11131374 discloses an industrial process for the product of water repellent fabric by treatment with a glyoxal-based resin crosslinking agent, an organo-fluorine compound and a isocyanate based cross-linking agent. Followed by heat treatment for 0.5-5 min. A similar process is disclosed in JP 2000129573.
[0010] An alternative proposal is to use poly-acids such as BTCA (butyl tetra carboxylic acid) or citric acid as crosslinking agents. These can esterify with the —OH groups of the cellulose to form a covalent cross-link. The covalent cross-link is not disrupted by water and this both prevents deformation of fabrics and assists return to a flat state. One of the difficulties with this approach is that a sodium hypophosphite catalyst is generally used to cause the esterification reaction to proceed and the treated articles require heat curing. Moreover, these poly-acid materials are highly water soluble and are difficult to deposit on fabrics.
[0011] A preferred durable press system suitable for domestic use should be a non-toxic, one component, catalyst-free system with low iron-cure times, have some affinity for the fabric surface and not cause fabric strength losses. It should also avoid the need for specialised equipment and the use of use of difficult materials such as vapour-phase formaldehyde.
BRIEF DESCRIPTION OF THE INVENTION
[0012] We have determined that excellent cross-linking benefits can be obtained by treating finished garments with a cellulose cross-linking agent that is thermally activated.
[0013] Accordingly, the present invention provides a method of treating finished garments comprising cellulosic material so as to cause cross-linking, which comprises the step of treating fabrics with an effective amount of a blocked cross-linking agent for cellulose, said cross-linking agent being thermally activated.
[0014] In the context of the present invention, the term ‘thermally activated’ is intended to mean that the cross-linking agent is ‘blocked’ to prevent reaction until the cross-linking agent is activated by the application of heat. In order to achieve cross-linking is preferable that at least two reactive sites of the cross-linking agents are blocked with a thermally labile blocking group.
[0015] Preferably the blocked cross-linking sites are selected such that, when activated, they are readily capable of reacting with hydroxy groups present in cellulose. More preferably the cross-linking reaction forms an ‘ester’ linkage, which in the context of the present invention includes linkages where the alpha carbon of the ester is replaced by a hetero-atom, preferably nitrogen. In the case of the alpha-carbon being so replaced the molecule is formally known as a carbamate.
[0016] Ideally, the reaction proceeds without the requirement for a catalyst. Catalysts can optionally be present. Suitable catalysts are selected depending on the particular blocking chemistry employed and, for example, include, pH modification agents and/or metal ions.
[0017] Preferably the cross-linking agent is bi-functional.
[0018] In one preferred embodiment of the invention the cross-linking agent is an at least bi-functional blocked polycarboxylic acid.
[0019] In another preferred embodiment of the invention the cross linking agent is an at least bi-functional blocked isocyanate.
[0020] By ‘bi-functional’ is meant that there are at least two blocked groups which can act as cross linking sites. Preferably, both of these are either blocked isocyanates or blocked carboxylic acids.
[0021] Preferably the blocked carboxylic acid is an ester with relatively weak ester bonds which can trans-esterify with cellulose. This is accomplished by forming the polyester between a poly-carboxylic acid and an alcohol (which term includes phenol) which is a good leaving group. The alcohols act as thermally labile ‘blocking agents’ for the carboxylic acid groups. Essentially the same result can be obtained by the use of carboxylic acid/imide linkages.
[0022] The present invention provides a method of treating finished garments comprising cellulosic materials so as to cause cross-linking which comprises the step of transesterifying the cellulosic material with an effective amount of an at least bi-functional blocked polycarboxylic acid.
[0023] Preferably said blocked polycarboxylic acid is blocked with an electron-withdrawing alcohol or imide.
[0024] The present invention further provides a method of treating finished garments comprising cellulosic materials so as to cause cross-linking which comprises the step of treating finished garments comprising cellulosic material with an effective amount of an at least bi-functional blocked isocyanate.
[0025] In the present invention the treatment is conducted as part of a domestic laundering operation applied to finished garments.
[0026] A further aspect of the present invention provides a composition for use in the methods described above.
[0027] Preferably, said composition will comprise a cross-linking agent which forms an ester linkage with the cellulose.
[0028] Preferably the cross-linking agent comprises either a blocked poly isocyanate or blocked poly carboxylic acid and which is thermally activated.
[0029] Preferably, the method of the invention comprises the step of curing the treated materials by heat treatment at a temperature of from 50 to 250C, more preferably at a temperature of from 100-200C.
[0030] More preferably, the method of the present invention further comprises the step of curing the treated materials by ironing or hot pressing. That a useful effect can be obtained by ironing after treatment is surprising.
[0031] Advantageously, the present method may be performed in the absence of vapour-phase formaldehyde and other components known from the prior art which are unsuitable for domestic use.
DETAILED DESCRIPTION OF THE INVENTION
[0032] As noted above the cellulose cross-linking agent can be a polycarboxylic acid or a blocked isocyanate. Preferred embodiments of each of these alternatives are discussed in further detail below.
[0033] In some embodiments the backbone of the cross-linking agent is polymeric in character, by which is meant that it comprises repeating structures. Typically, the backbone comprises a sufficiently long polymeric structure (preferably 2-12 carbon-carbon bond lengths) to fulfil its function as a bridging structure between the two or more reactive groups.
[0000] A. Blocked Polycarboxylicacids:
[0034] Polyesters suitable for use in the present invention comprise a polycarboxylic acid esterified with a ‘leaving’ group which is an alcohol or an imide. The polycarboxylic acid preferably has 2-6 carboxyl groups available for esterification. Typically each of the carboxyl groups will be esterified to produce a polyester.
[0035] Most preferably, the polycarboxylic acid has two carbonyl groups available for esterification and typically these are at opposite ends of an essentially linear polycarboxylic acid. In a preferred embodiment the polyester takes the form:
R 1 O—CO-L-CO—OR 2
Where R 1 O— and —OR 2 are the same or different alcohol residues, and —CO-L-CO— is the residue of the polycarboxylic acid. L is a linking group, which may be substituted, and generally comprises a 2-12 carbon backbone.
Polycarboxylic Acids:
[0036] Preferred polycarboxylic acids include one or more of
malonic Acid, methylmalonic acid, ethylmalonic acid, butylmalonic acid, dimethylmalonic acid, diethylmalonic acid; succinic acid, methylsuccinic acid, 2,2-dimethylsuccinic acid, 2-ethyl-2-methylsuccinic acid, 2,3-dimethylsuccinic acid, meso-2,3-dimethylsuccinic acid, glutaric acid, 2-methylglutaric acid, 3-methylglutaric acid, 2,2-dimethylglutaric acid, 3,3-dimethyl-glutaric acid, adipic acid, 3-methyladipic acid, 3-tert-butyladipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,11-undecanecarboxylic acid, undecanedioic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, hexadecanedioic acid, docosanedioic acid, tetracosanedioic acid, tricarballylic acid, 1,2,3,4-butanetetracarboxylic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, trans-glutaconic acid, trans-beta-hydromuconic acid, trans-traumatic acid, trans,trans-muconic acid, cis-aconitic acid, trans-aconitic acid, malic acid, citramalic acid,
[0063] isopropylmalic acid,
3-hydroxy-3-methylglutaric acid, tartaric acid, mucic acid, citric acid, dihydroxyfumaric acid, diglycolic acid, 3,6-dioxaoctanedioic acid, 3,3′-thiodipropionic acid, 3,3′-dithiodipropionic acid, trans-DL-1,2-cyclopentanedicarboxylic acid, 3,3-tetramethyleneglutaric acid, camphoric acid, cyclohexylsuccinic acid, 1,1-cyclohexanediacetic acid, trans-1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic aicd, 1,4-cyclohexanedicarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid, Kemp's triacid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4,5,6-cyclohexanehexacarboxylic acid 4-Carboxyphenoxyacetic acid, 1,4-phenylenediaectic acid, 1,4-phenylenedipropionic acid, 1,4-phenylenediacrylic acid, 2-Carboxybenzenepropanioc acid, 4,4′-oxybis(benzoic acid), phthalic acid, isophthalic acid, terephthalic acid, 1,2,3-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid,
[0091] mellitic acid,
2-methoxyisophthalic acid, diphenic acid, 4,4′-biphenyldicarboxylic acid, 2,6-Napthalenedicarboxylic acid, 3-carboxy-1,4-dimethyl-2-pyroleacetic acid, Oligomers (and co-oligomers) of unsaturated carboxylic acids can be used. Suitable materials include oligomers of acrylic acid, methacrylic acid, crotonic acid, vinylacetic acid, 4-pentenoic acid, and/or maleic acid
[0098] The acid can comprise a heteroatom. Nitrogen is a preferred heteroatom. Suitable N-containing acids include:
iminodiacetic acid, 3-aminophthalic acid, 2-aminoterephthalic acid, 5-aminoisophthalic acid, ethylenediamine-N,N′-diacetic acid, methyliminodiacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, 1,6-diaminohexane-N,N,N′,N′-tetraacetic acid, trans-1,2-diaminocyclohexane-N,N,N′,N′,-tetraacetic acid, triethylenetetraminehexaacetic acid, 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid, ethylenebis(oxyethylenenitrilo)tetraacetic acid, diethylenetriaminepentaacetic acid, aspartic acid, glutamic acid, 2-methylglutamic acid, 2-aminoadipic acid, 3-aminoadipic acid, 2,6-diaminopimelic acid, cystine N-benzyliminodiacetic acid, N-(2-carboxyphenyl)glycine, 2,2′-(ethylenedioxy)dianiline-N,N,N′,N′-tetraacetic acid.
[0121] porphobilinogen,
4,5-imidazoledicarboxylic acid, 2,2′-bipyridine-4,4′-dicarboxylic acid, 3,4-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 6-methyl-2,3-pyridinedicarboxylic acid, 2,6-dimethyl-3,5-pyridinedicarboxylic acid
[0127] In the case where a nitrogen is present, this may be quaternerised with an appropriate quaternerising agent.
[0128] Known quaternerising agents include CH 3 Cl, CH 3 I, and (CH 3 ) 2 SO 4 .
[0000] Alcohols:
[0129] The alcohol may have a linear, branched or ring structure.
[0130] Preferred alcohols comprise 5- or 6-membered rings which have electron-withdrawing groups in the ortho- and para-positions relative to the alcoholic hydrogen. Examples of such preferred alcohols include N-hydroxysuccinimide and hydroxybenzotriazole. In addition, the alcohol may be in the enol form of a ketone. As noted above, and for the avoidance of doubt, phenols are considered alcohols for the purpose of this specification.
[0131] Suitable electron withdrawing substituents on the ring include one or more of: NO 2 , CN, CO 2 H, CO 2 R, CONHR, CONR 2 , CHO, COR, SO 2 R, SO 2 OR, SO 2 OAr, NO, Ar, NR 3 ⊕ , SR 2 ⊕ , NH 3 ⊕ , F, Cl, Br, I, OAr, SH, SR, OH, OR, CH═CR 2 . The electron withdrawal can be due to either inductive or resonance effects.
[0132] Phenol derivatives with at least one electron-withdrawing substituent are preferred.
[0000] Preferred phenol derivatives include:
[0000]
Vanillin,
Ethyl vanillin,
Eugenol,
isoeuginol,
salicylic acid, ethyl salicylate,
4-cyanophenol,
hydroxyacetophenone,
trichlorophenol,
2,6-dimethoxyphenol,
4-aminophenol (and quaternerised salt),
dimethylaminophenol (and quaternerised salt),
chlorophenol, bromophenol, iodophenol, fluorophenol, dichlorophenol, dibromophenol, diiodophenol, difluorophenol,
hydroxythiophenol,
aminocresol,
4-amino-2,5-dimethylphenol,
6-amino-2,4-dichloro-3-methylphenol, nitrophenol, dinitrophenol,
hydroxypropiophenone,
2′-hydroxy-5′-methylacetophenone,
5′-chloro-2′-hydroxyacetophenone,
acetovanillone,
4-hydroxybenzaldehyde,
o-vanillin,
4-hydroxy-3-methylbenzaldehyde,
2-chloro-4-hydroxybenzaldehyde,
2-hydroxy-5-methoxybenzaldehyde,
3-ethoxy-4-hydroxybenzaldehyde,
5-nitrovanillin,
3-methoxy-5-nitrosalicyaldehyde,
4-hydroxybenzoic acid,
methylsalicylic acid,
chlorosalicylic acid,
methoxysalicylic acid,
aminosalicylic acid,
methylsalicylic acid,
formylsalicylic acid,
hydroxyisophthalic acid,
methyl hydroxybenzoate,
ethyl hydroxybenzoate,
propyl hydroxybenzoate,
methyl 5-methylsalicylate,
ethyl 5-methylsalicylate,
hydroxybenzamide,
5-chloro-2-hydroxybenzamide,
5-acetylsalicylamide,
2-amino-4-(ethylsulfonyl)phenol
[0178] Particularly preferred alcohols include trichlorophenol, isoeuginol, vanillin, 4-cyanophenol, ethyl salicylate, 2,6-dimethoxy phenol, 4-aminophenol and dimethylamino phenol. As noted above, imides can also be used as the ‘alcohol’.
[0179] A preferred imide material is N-hydroxysuccinimide.
[0180] The alcohol leaving group can have functional properties which give it some utility after the transesterification reaction. One such property is that of a perceptible odour. For example, a notable odour of cloves is obtained with weak isoeuginol esters upon the application of heat (i.e. on ironing). This can act as a useful cue to the user that the reaction is proceeding.
[0181] Preferred polyesters include the trichlorophenol diester of succinic acid, the trichlorophenol diester of BTCA, the N-hydroxysuccinimide diester of succinic acid, the isoeugenol diester of succinic acid, and the vanillin diester of succinic acid.
[0182] The polyester will typically only have one type of alcohol present, although it is possible to envisage ‘mixed’ esters in which two or more, different types of alcohol are present.
[0183] It is particularly preferred that the polyester has a molecular weight below 1500 Dalton. It is believed that the cellulosic materials will stiffen if larger molecular weight materials are used.
[0184] While the polyester can be applied from a non-aqueous solvent (such as THF) it is preferable to apply the material from a wholly or partly aqueous solvent.
[0000] B. Blocked Polyisocyanates:
[0185] In another class of embodiments of the invention the treatment agent is a blocked isocyanate.
[0186] Blocked isocyanate is described at length and defined in ‘Progress in Organic Coatings’ 36 (1999) 148-172.
[0187] Preferably, but not exclusively, the blocked isocyanate is chemically blocked. Such molecules include materials which are derived from isocyanate compounds by reaction with an active hydrogen compound. However, it is also known to produce blocked isocyanate via other routes not involving the reaction of an isocyanate, these are still known in the art as blocked isocyanate. Similarly, while cross-linking most reactions of the blocked isocyanate will generate an isocyanate as an intermediate, reaction schemes have been suggested in which the blocked isocyanate reacts without the formation of such an intermediate. It is also known that isocyanate can form thermally unstable dimers or higher polymeric forms, generally known as ‘uretdiones’ these are also considered to be examples of blocked isocyanate for the purposes of the present invention.
[0188] As suitable polycarboxylic acids and ‘blocking’ alcohols were described above, so suitable polyisocyanates and blocking groups are described below.
[0000] Polyisocyanates:
[0000]
1,4-Diisocyanatobutane
1,6-Diisocyanatohexane
1,8-Diisocyanatooctane
1,10-Diisocyanatodecane
1,12-Diisocyanatododecane
Tetradecamethylenediisocyanate
Trimethylhexanediisocyanate
Tetramethylhexanediisocyanate
trans-11,4-cyclohexylene diisocyanate
Isophorone diisocyanate
1,3-Bis(isocyanatomethyl)cyclohexane
4,4′-methylenebis(cyclohexyl isocyanate)
Trimethylolpropane triisocyanate
1-isocyanato-2,4-bis[(4-isocyanatocyclohexyl)methyl]-cyclohexane
α,4-Tolylene diisocyanate
m-xylene diisocyanate
Toluene 2,4-diisocyanate
Toluene 2,5-diisocyanate
1,3-Bis(1-isocyanato-1-methylethyl)benzene
1,3-Phenylene diisocyanate
1,4-Phenylene diisocyanate
2,6-Tolylene diisocyanate
4,4′-oxybis(phenyl isocyanate)
Naphthylene-1,5-diisocyanate
Triphenyl methane-4,4′,4″-triisocyanate
2,4-diisocyanato-1-(4-isocyanatophenoxy)-benzene
1,3,5-triisocyanato-2-methyl-benzene
Diphenylmethane-2,4,4′,-triisocyanate
[0217] Also envisaged as suitable are biuret-isocyanurate- or urethane-group-containing modification products of the above mentioned simple polyisocyanates, for example tris-(6-isocyanatohexyl)-biuret and its higher homologs; polyisocyanates containing isocyanurate groups obtainable by the trimerisation of aliphatic and/or aromatic diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, especially tri-(6-isocyanatohexyl)-isocyanurate
[0218] Polyisocyanates formed by the reaction of an excess of diisocyanate with polyhydric alcohols followed by the removal of unreacted diisocyanate excess by distillation.
[0219] Examples of simple polyhydric alcohols include:
Glycerol 1,2-dihydroxypropane Trimethylol propane Pentaerythritol Ethylene glycol Diethyleneglycol Triethyleneglycol Tetraethyleneglycol Pentaethyleneglycol Hexaethylene glycol Polyethyleneglycol Polypropyleneglycol Dipentaerythritol Triethanolamine (which can be optionally quaternerised)
[0234] The diisocyanates can also be reacted with polyols containing anionic groups such as carboxylic acids, sulphone acids and phosphoric acids, and especially hydroxyacids followed by removal of excess unreacted diisocyanate by distillation in a similar manner. Suitable hydroxyacids include:
2,2-bis(hydroxymethyl)acetic acid 2,2-bis(hydroxymethyl)propionic acid 2,2-bis(hydroxymethyl)butionic acid 2,2,2-tris(hydroxymethyl)acetic acid Tartaric acid
[0240] The acid groups can optionally be partially or completely neutralised to make the iscoyanate-containing molecule water soluble or water dispersible.
[0241] Polyisocyanates can also be formed by reaction of diisocyanates with polyamines followed by removal of excess unreacted diisocyanate by distillation.
[0242] Examples of suitable polyamines include:
Diethylenetriamine N-(2-aminoethyl)-1,3-propanediamine 3,3′-diamino-N-methyldipropylamine N-(3-aminopropyl)-1,3-propanediamine Spermidine Bis(hexamethylene)triamine 2,2′-(ethylenedioxy)bis(ethylamine) 4,7,10-trioxa-1,13-tridecanediamine Glycerol tris(poly(propylene glycol)amine terminated) ether Chitosan
[0253] Polyisocyanates formed by the conversion from polyamines, for example by treatment with phosgene are also included.
[0254] Hexamethylene diisocyanate is a particularly preferred isocyanate for use in the present invention.
[0000] Polyisocyanate Blocking Agents:
[0255] These are analogous to the thermally-labile alcohol blocking agents used for the esters and described above. As in the case of the preferred materials described for blocking esters the blocking agents for the isocyanates can also be phenols. As noted above the isocyanates generally react with cellulose to form carbamates, which are considered examples of the more general class of esters. It is believed that some isocyanates, will however react to form ‘true’ esters.
[0256] Preferred phenols again have electron withdrawing substituents in the ortho and/or para position relative to the alcoholic proton.
[0257] Oximes, (an oxime is formed by the reaction of hydroxylamine with a carbonyl compound) can be used to block isocyanates. Examples of suitable ketones that form oximes by reaction with hydroxylamine include:
Tetramethylcyclobutanedione Methyl n-amyl ketone Methyl isoamyl ketone Methyl 3-ethylheptyl ketone Methyl 2,4-dimethylpentyl ketone Methyl ethyl ketone Cyclohexanone Methyl isopropyl ketone Methyl isopropyl ketone Methyl isobutyl ketone Diisobutyl ketone Methyl t-butyl ketone Diisopropyl ketone 2,2,6,6-Tetramethylcyclohexanone
[0272] Suitable non-phenol alcohol blocking agents include:
[0273] Mono-ethers of ethylene glycol such as 2-ethoxyethyl alcohol, 2-ethoxyethoxyethyl alcohol, 2-ethylhexyloxyethyl alcohol, 2-butoxyethyl alcohol, and 2-butoxyethoxyethyl alcohol
N,N-Glycol amides such as N,N-dibutylglycolamide N-hydroxysuccinimide
[0275] Suitable amides and imides blocking agents include:
Acetanilide N-methylacetamide Caprolactam 2-pyrrolidone Succinimide
[0281] Suitable imidazole and amidine blocking agents include:
2-ethyl-4-methylimidazole 2-methylimidazole 1,4,5,6-tetrahydropyrimidine guanidine 2,4-dimethylimidazoline 4-methylimidazoline 2-phenylimidazoline 4-methyl-2-phenylimidazoline
[0290] Suitable Pyrazole and triazole blocking agents include:
pyrazole 3-methylpyrazole 3,5-dimethylpyrazole 1,2,4-triazole Benzotriazole
[0296] Secondary and especially hindered amines can be used to block isocyanates.
[0297] Suitable active methylene blocking agents include:
diethyl malonate t-butyl methyl malonate Meldrum's acid (isopropylidene malonate) Ethyl acetoacetate t-butyl acetoacetate
[0303] Particularly preferred blocking agents are Meldrum's Acid, Phenol, 4-Nitrophenol, 4-Methoxyphenol, and/or Methyl Salicylate. The most preferred blocking agents are diethyl malonate, succinimide and sodium bisulphite.
[0304] Both the isocyanates and the carboxylic acids described above can be mono-blocked by reaction of only one of the characteristic reactive groups by a suitable blocking agent.
[0305] The remaining free reactive group(s) can then be reacted with a bi-functional further linking group (such as a polyol or polyamine) to form blocked structures which (taking the mono-blocked acids and a diol as an example) have the form:
R 1 O—CO-L 1 -CO—OMO—CO-L 2 -CO—OR 2
Where:
R 1 O— and —OR 2 are the same or different alcohol residues, -CO-L 1 -CO— and —CO-L2-CO— are the same or different residue of polycarboxylic acid, and, —OMO— is the residue of the polyol.
[0306] Similar structures can be prepared from the isocyanates.
[0307] Methods of forming mono-blocked isocyanates include blocking of diisocyanates where each isocyanate group has a different reactivity thus one or more groups become preferentially blocked. Alternatively, the blocking agent can be added to a large excess of diisocyanate and the unreacted diisocyanate removed by distillation upon completion of blocking. Similar considerations apply to esters.
[0308] Reaction of the mono-blocked cross-linking agent with either a polyol or polyamine can involve either reaction with all the available hydroxy or amine groups to give a 100% modified polyol or polyamine.
[0309] By controlling the amount of mono-blocked cross-linking added, structures with both modified and unmodified hydroxy and amine groups can be formed. Such structures are capable of self-crosslinking upon removal of the blocking groups.
[0310] Suitable polyols include those found among the alcohols described previously as being suitable for blocking isocyanates or carboxylic acids.
[0311] Particularly preferred polyols are:
[0312] Sugars such as sorbitol, mannitol, xylose, fructose, galactose, mannose, glucose, altrose, lactose, cellobiose, sucrose,
[0313] Oligo and polysaccharides, preferentially β-1,4-linked oligo- and polysaccharides.
[0314] Particularly preferred are polyols are cellulose and its derivatives, or other polysaccharides which have the ability to recognise cellulose, example of which include locus bean gum and guar gum.
[0315] Suitable polyamines include:
Diethylenetriamine N-(2-aminoethyl)-1,3-propanediamine 3,3′-diamino-N-methyldipropylamine N-(3-aminopropyl)-1,3-propanediamine Spermidine Bis(hexamethylene)triamine 2,2′-(ethylenedioxy)bis(ethylamine) 4,7,10-trioxa-1,13-tridecanediamine Glycerol tris(poly(propylene glycol)amine terminated) ether Chitosan
[0326] Optionally, unreacted amino groups can be rendered cationic by modification with quaternerising agents such as methyl iodide, dimethyl sulphate and the like. Such cationic modification improves the substantivity of the materials.
[0327] By use of a secondary linking group ‘M’ which can recognise (as in the case of polysaccharides) or otherwise bind (as in the case of the cationics) to a cellulosic substrate the efficiency of deposition of the cross-linking agents can be significantly improved.
[0000] Carriers and Product Form:
[0328] Compositions of the present invention are preferably formulated into fabric care compositions comprising a solution, dispersion or emulsion comprising a cross-linking agent.
[0329] The compositions of the invention will generally comprise a textile compatible carrier.
[0330] In the context of the present invention the term “textile compatible carrier” includes a component which can assist in the interaction of the cellulose cross-liking agent with a textile. The carrier can be a simply a solvent for the cross-linking agent, although the carrier can also provide benefits in addition to those provided by the cross-linking agent e.g. softening, cleaning etc. Preferably, the carrier is a detergent-active compound or a textile softener or conditioning compound or a detergent.
[0331] If the composition is to be used in a laundry process as part of a conventional fabric treatment product, such as a rinse conditioner or main wash product, it is preferable if the level of cross-linking agent is from 0.01% to 10%, more preferably 0.05% to 7.5%, most preferably 0.1 to 5 wt % of the total composition.
[0332] If, however, the composition is to be used in a laundry process as a product to specifically treat the fabric to reduce creasing, higher levels of cross-linking agent can be used. Preferred amounts are from 0.01% to 15%, more preferably 0.05% to 10%, for example from 0.1 to 7.5 wt % of the total composition.
[0333] If the composition is to be used in a spray product it is preferred that the level of cross-linking agent is from 0.5 to 20 wt %, preferably 1 to 20 wt % of the total composition.
[0334] As noted above, the method of the invention generally comprises the step of applying a composition of the cross-linking agent to garments and curing the composition, preferably by ironing. The composition may be applied to the fabric by conventional methods such as dipping, spraying or soaking, for example.
[0335] The fabric care composition of the invention preferably comprises a solution, dispersion or emulsion comprising a cross-linking agent and a textile compatible carrier. The textile compatible carrier facilitates contact between the fabric and the ingredients of the composition. The textile compatible carrier may be water or a surfactant. However, when it is water, it is preferred that a perfume is present.
[0336] In one particularly preferred embodiment, the composition may be provided in a form suitable for spraying onto a fabric. The fabric may then be dried, e.g. in a tumble dryer, and then ironed to cure the composition.
[0337] If this is the case, it is preferred that the polycarboxylic acid or derivative thereof is present at a level from 0.5 to 20 wt %, preferably 0.5 to 10 wt %, of the total composition. If the product is to be used in a spray on product it is also beneficial if wetting agents are also present such as alcohol ethoxylates for example, Synperonic A7.
[0338] For a spray on formulation anionic surfactants may be present.
[0339] Suitable spray dispensing devices are disclosed in WO 96/15310 (Procter & Gamble) and are incorporated herein by reference. Alternatively, the composition may be applied through the irons water tank, a separate reservoir or a spray cartridge in an iron, as described in EP1201816 and WO 99/27176.
[0340] Spray products may contain water and/or other solvents as a carrier molecule.
[0341] It is particularly advantageous, and surprising, that the composition can be cured by ironing, even under domestic conditions. Moreover, a steam iron can be used, which is desirable to aid wrinkle removal, with no deleterious effects on the curing process.
[0342] A further advantage of the method of the invention is that, when the composition is applied as a spray, one application is sufficient to obtain benefits after subsequent washes.
[0343] In a washing process, as part of a conventional textile washing product, such as a detergent composition, the textile-compatible carrier will typically be a detergent-active compound. Whereas, if the textile treatment product is a rinse conditioner, the textile-compatible carrier will be a textile softening and/or conditioning compound. These are described in further detail below.
[0344] The cross-linking agent can be used to treat the textile in the wash cycle of a laundering process. The cross-linking agent can also be used in the rinse cycle, or, preferably applied prior to or during ironing and/or pressing.
[0345] The composition of the invention may be in the form of a liquid, solid (e.g. powder or tablet), a gel or paste, spray, stick or a foam or mousse. Examples include a soaking product, a rinse treatment (e.g. conditioner or finisher) or a main-wash product. Spray products are particularly suited to application as part of an ironing or pressing process.
[0346] Liquid compositions may also include an agent which produces a pearlescent appearance, e.g. an organic pearlising compound such as ethylene glycol distearate, or inorganic pearlising pigments such as microfine mica or titanium dioxide (TiO 2 ) coated mica. Liquid compositions may be in the form of emulsions or emulsion precursors thereof.
[0000] Detergent Active Compounds:
[0347] If the composition of the present invention is itself in the form of a detergent composition, the textile-compatible carrier may be chosen from soap and non-soap anionic, cationic, nonionic, amphoteric and zwitterionic detergent active compounds, and mixtures thereof.
[0348] Many suitable detergent active compounds are available and are fully described in the literature, for example, in “Surface-Active Agents and Detergents”, Volumes I and II, by Schwartz, Perry and Berch.
[0349] The preferred textile-compatible carriers that can be used are soaps and synthetic non-soap anionic and nonionic compounds.
[0350] Anionic surfactants are well-known to those skilled in the art. Examples include alkylbenzene sulphonates, particularly linear alkylbenzene sulphonates having an alkyl chain length of C 8 -C 15 ; primary and secondary alkylsulphates, particularly C 8 -C 15 primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; and fatty acid ester sulphonates. Sodium salts are generally preferred.
[0351] Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the C 8 -C 20 aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C 10 -C 15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non-ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide).
[0352] Cationic surfactants that may be used include quaternary ammonium salts of the general formula R 1 R 2 R 3 R 4 N + X − wherein the R groups are independently hydrocarbyl chains of C 1 -C 22 length, typically alkyl, hydroxyalkyl or ethoxylated alkyl groups, and X is a solubilising cation (for example, compounds in which R 1 is a C 8 -C 22 alkyl group, preferably a C 8 -C 10 or C 12 -C 14 alkyl group, R 2 is a methyl group, and R 3 and R 4 , which may be the same or different, are methyl or hydroxyethyl groups); and cationic esters (for example, choline esters) and pyridinium salts.
[0353] The total quantity of detergent surfactant in the composition is suitably from 0.1 to 60 wt % e.g. 0.5-55 wt %, such as 5-50 wt %.
[0354] Preferably, the quantity of anionic surfactant (when present) is in the range of from 1 to 50% by weight of the total composition. More preferably, the quantity of anionic surfactant is in the range of from 3 to 35% by weight, e.g. 5 to 30% by weight.
[0355] Preferably, the quantity of nonionic surfactant when present is in the range of from 2 to 25% by weight, more preferably from 5 to 20% by weight.
[0356] Amphoteric surfactants may also be used, for example amine oxides or betaines.
[0000] Builders:
[0357] The compositions may suitably contain from 10 to 70%, preferably from 15 to 70% by weight, of detergency builder. Preferably, the quantity of builder is in the range of from 15 to 50% by weight.
[0358] The detergent composition may contain as builder a crystalline aluminosilicate, preferably an alkali metal aluminosilicate, more preferably a sodium aluminosilicate.
[0359] The aluminosilicate may generally be incorporated in amounts of from 10 to 70% by weight (anhydrous basis), preferably from 25 to 50%. Aluminosilicates are materials having the general formula:
0.8-1.5 M 2 O. Al 2 O 3 . 0.8-6 SiO 2
where M is a monovalent cation, preferably sodium. These materials contain some bound water and are required to have a calcium ion exchange capacity of at least 50 mg CaO/g. The preferred sodium aluminosilicates contain 1.5-3.5 SiO 2 units in the formula above. They can be prepared readily by reaction between sodium silicate and sodium aluminate, as amply described in the literature.
[0360] Alternatively, or additionally to the aluminosilicate builders, phosphate builders may be used.
[0000] Textile Softening and/or Conditioner Compounds:
[0361] If the composition of the present invention is in the form of a textile conditioner composition, the textile-compatible carrier will be a textile softening and/or conditioning compound (hereinafter referred to as “textile softening compound”), which may be a cationic or nonionic compound.
[0362] The softening and/or conditioning compounds may be water insoluble quaternary ammonium compounds. The compounds may be present in amounts of up to 8% by weight (based on the total amount of the composition) in which case the compositions are considered dilute, or at levels from 8% to about 50% by weight, in which case the compositions are considered concentrates.
[0363] Compositions suitable for delivery during the rinse cycle may also be delivered to the textile in the tumble dryer if used in a suitable form. Thus, another product form is a composition (for example, a paste) suitable for coating onto, and delivery from, a substrate e.g. a flexible sheet or sponge or a suitable dispenser during a tumble dryer cycle.
[0364] Suitable cationic textile softening compounds are substantially water-insoluble quaternary ammonium materials comprising a single alkyl or alkenyl long chain having an average chain length greater than or equal to C 20 . More preferably, softening compounds comprise a polar head group and two alkyl or alkenyl chains having an average chain length greater than or equal to C 14 . Preferably the textile softening compounds have two, long-chain, alkyl or alkenyl chains each having an average chain length greater than or equal to C 16 .
[0365] Most preferably at least 50% of the long chain alkyl or alkenyl groups have a chain length of C 18 or above. It is preferred if the long chain alkyl or alkenyl groups of the textile softening compound are predominantly linear.
[0366] Quaternary ammonium compounds having two long-chain aliphatic groups, for example, distearyldimethyl ammonium chloride and di(hardened tallow alkyl) dimethyl ammonium chloride, are widely used in commercially available rinse conditioner compositions. Other examples of these cationic compounds are to be found in “Surface-Active Agents and Detergents”, Volumes I and II, by Schwartz, Perry and Berch. Any of the conventional types of such compounds may be used in the compositions of the present invention.
[0367] The textile softening compounds are preferably compounds that provide excellent softening, and are characterised by a chain melting Lβ to Lα transition temperature greater than 25° C., preferably greater than 35° C., most preferably greater than 45° C. This Lβ to Lα transition can be measured by DSC as defined in “Handbook of Lipid Bilayers”, D Marsh, CRC Press, Boca Raton, Fla., 1990 (pages 137 and 337).
[0368] Substantially water-insoluble textile softening compounds are defined as textile softening compounds having a solubility of less than 1×10 −3 wt % in demineralised water at 20° C. Preferably the textile softening compounds have a solubility of less than 1×10 −4 wt %, more preferably less than 1×10 −8 to 1×10 −6 wt %.
[0369] Especially preferred are cationic textile softening compounds that are water-insoluble quaternary ammonium materials having two C 12-22 alkyl or alkenyl groups connected to the molecule via at least one ester link, preferably two ester links. Di(tallowoxyloxyethyl) dimethyl ammonium chloride and/or its hardened tallow analogue are especially preferred of the compounds of this type. Other preferred materials include 1,2-bis(hardened tallowoyloxy)-3-trimethylammonium propane chloride. Their methods of preparation are, for example, described in U.S. Pat. No. 4,137,180 (Lever Brothers Co). Preferably these materials comprise small amounts of the corresponding monoester as described in U.S. Pat. No. 4,137,180, for example, 1-hardened tallowoyloxy-2-hydroxy-3-trimethylammonium propane chloride.
[0370] Other useful cationic softening agents are alkyl pyridinium salts and substituted imidazoline species. Also useful are primary, secondary and tertiary amines and the condensation products of fatty acids with alkylpolyamines.
[0371] The compositions may alternatively or additionally contain water-soluble cationic textile softeners, as described in GB 2 039 556B (Unilever).
[0372] The compositions may comprise a cationic textile softening compound and an oil, for example as disclosed in EP-A-0829531.
[0373] The compositions may alternatively or additionally contain nonionic textile softening agents such as lanolin and derivatives thereof.
[0374] Lecithins are also suitable softening compounds.
[0375] Nonionic softeners include Lβ phase forming sugar esters (as described in M Hato et al Langmuir 12, 1659, 1666, (1996)) and related materials such as glycerol monostearate or sorbitan esters. Often these materials are used in conjunction with cationic materials to assist deposition (see, for example, GB 2 202 244). Silicones are used in a similar way as a co-softener with a cationic softener in rinse treatments (see, for example, GB 1 549 180).
[0376] The compositions may also suitably contain a nonionic stabilising agent. Suitable nonionic stabilising agents are linear C 8 to C 22 alcohols alkoxylated with 10 to 20 moles of alkylene oxide, C 10 to C 20 alcohols, or mixtures thereof.
[0377] Advantageously the nonionic stabilising agent is a linear C 8 to C 22 alcohol alkoxylated with 10 to 20 moles of alkylene oxide. Preferably, the level of nonionic stabiliser is within the range from 0.1 to 10% by weight, more preferably from 0.5 to 5% by weight, most preferably from 1 to 4% by weight. The mole ratio of the quaternary ammonium compound and/or other cationic softening agent to the nonionic stabilising agent is suitably within the range from 40:1 to about 1:1, preferably within the range from 18:1 to about 3:1.
[0378] The composition can also contain fatty acids, for example C 8 to C 24 alkyl or alkenyl monocarboxylic acids or polymers thereof. Preferably saturated fatty acids are used, in particular, hardened tallow C 16 to C 18 fatty acids. Preferably the fatty acid is non-saponified, more preferably the fatty acid is free, for example oleic acid, lauric acid or tallow fatty acid. The level of fatty acid material is preferably more than 0.1% by weight, more preferably more than 0.2% by weight. Concentrated compositions may comprise from 0.5 to 20% by weight of fatty acid, more preferably 1% to 10% by weight. The weight ratio of quaternary ammonium material or other cationic softening agent to fatty acid material is preferably from 10:1 to 1:10.
[0000] Other Components
[0379] Compositions according to the invention may comprise soil release polymers such as block copolymers of polyethylene oxide and terephthalate.
[0380] Other optional ingredients include emulsifiers, electrolytes (for example, sodium chloride or calcium chloride) preferably in the range from 0.01 to 5% by weight, pH buffering agents, and perfumes (preferably from 0.1 to 5% by weight).
[0381] Further optional ingredients include non-aqueous solvents, fluorescers, colourants, hydrotropes, antifoaming agents, enzymes, optical brightening agents, and opacifiers.
[0382] Suitable bleaches include peroxygen bleaches. Inorganic peroxygen bleaching agents, such as perborates and percarbonates are preferably combined with bleach activators. Where inorganic peroxygen bleaching agents are present the nonanoyloxybenzene sulphonate (NOBS) and tetra-acetyl ethylene diamine (TAED) activators are typical and preferred.
[0383] Suitable enzymes include proteases, amylases, lipases, cellulases, peroxidases and mixtures thereof.
[0384] In addition, compositions may comprise one or more of anti-shrinking agents, anti-wrinkle agents, anti-spotting agents, germicides, fungicides, anti-oxidants, UV absorbers (sunscreens), heavy metal sequestrants, chlorine scavengers, dye fixatives, anti-corrosion agents, drape imparting agents, antistatic agents and ironing aids. The lists of optional components are not intended to be exhaustive.
[0385] In order that the invention may be further and better understood it will be described below with reference to several non-limiting examples.
EXAMPLES
Synthesis Examples
Example 1
Synthesis of 2,4,6-Trichlorophenol Diester of Butanetetracarboxylic Acid
[0386] Butane tetracarboxylic acid (BTCA) (20.84 g, 0.089 mol) and 2,4,6-trichlorophenol (35.80 g, 0.18 mol) were weighed into a RB flask (250 cm 3 ). Nitrogen was flushed through the flask for 15 minutes, then distilled THF (150 cm 3 ) was added. After stirring under nitrogen for 30 minutes, diisopropyl-carbodiimide (29.0 cm 3 , 0.18 mol) was added dropwise over 20 minutes. The reaction was allowed to stir overnight under nitrogen. The mixture was filtered, washed with THF then stirred for one hour to ensure that formation of precipitate was complete. The solvent was removed to afford the crude product. This was washed several times with dichoromethane to yield the product upon removal of the solvent from the filtrate.
Example 2
Synthesis of 2,4,5-Trichlorophenol Diester of Succinic Acid
[0387] Succinic acid (1.5 g, 0.013 mol) was dissolved in DMSO (50 cm 3 ). 1,1′-Carbonyldiimidazole (5.0 g, 0.03 mol) was added and the mixture stirred for 30 mins at room temperature. 2,4,5-Trichlorophenol (5.05 g, 0.026 mol) was then added and the mixture stirred at room temperature overnight. The mixture was added to water, filtered, then washed with water followed by diethyl ether to yield a white solid (2.03 g, 33%) δ H (500 MHz; CDCl 3 ) 3.07 (4H, s, CH 2 —CH 2 —C(O)—O—) and 7.55 & 7.29 (4H, s, Ph)
Example 3
Synthesis of N-Hydroxysuccinimide Diester of Succinic Acid
[0388] Succinic acid (2.0 g, 0.017 mol) was dissolved in THF (50 cm 3 ) 1,1′-Carbonyldiimidazole (5.49 g, 0.034 mol) was added and the mixture stirred for 30 mins at room temperature. N-Hydroxysuccinimide (3.89 g, 0.034 mol) was added and the mixture stirred at room temperature overnight. The mixture was added to water, filtered, then washed with water then diethyl ether to yield a white solid (2.0 g, 38%) δ H (500 MHz; CDCl 3 ) 2.59 (8H, s, CH 2 —CH 2 —CO—N—) and 2.89 (4H, s, CH 2 —CH 2 —C(O)—O—)
Example 4
Synthesis of Vanillin Diester of Succinic Acid
[0000] (1) Organic Solvent Method:
[0389] Vanillin (9.82 g, 64.5 mMols) was dissolved in anhydrous THF (100 cm 3 ) with stirring at room temperature and under nitrogen. Anhydrous sodium carbonate (8.2 g, 77.4 mMols, 1.2 equiv) was then added and stirring was continued for 30 mins. Succinyl chloride (5 g, 32.25 mMols, 0.5 equiv) was then added dropwise to the slurry over 20 mins, the mixture was then stirred in the dark for a further 18 hours. The mixture was then filtered and the solvent removed from the filtrate under reduced pressure to give an off-white solid. The crude product was then recrystallised from IPA to give a white solid (2.7 g, 24%). δ H (500 MHz; CDCl 3 ) 3.08 (2H, s, —CH 2 —C(O)—O—), 3.89 (3H, s, —OCH 3 ), 7.27-7.50 (3H, m, Ph) and 9.95 (1H, s, —CHO).
[0000] (2) Schotten-Baumann Method:
[0390] Sodium Hydroxide (1.3 g, 32.5 mmols) was dissolved in distilled water (100 cm 3 ). To this solution vanillin (4.91 g, 32.5 mmols) was added and the solution was stirred to give a light yellow solution. The solution was then cooled to 0° C. prior to the dropwise addition of succinyl chloride (2.5 g, 16.25 mmols). The mixture was then allowed to warm to room temperature and stirring was continued for a further 10 mins to give a light yellow precipitate. The mixture was then poured into water (200 cm 3 ) and stirred at room temperature for 30 mins. The solution was filtered and the solid material retained. This crude product was then recrystallised to give a white solid (0.84 g, 13%).
Example 5
Synthesis of 4-Cyanophenol Diester of Succinic Acid
[0391] 4-Cyanophenol (7.7 g, 64.5 mMols) was dissolved in anhydrous THF (100 cm 3 ) with stirring at room temperature and under nitrogen. Anhydrous sodium carbonate (8.2 g, 77.4 mMols, 1.2 equivalents) was then added and stirring was continued for a further 10 mins. Succinyl chloride was then added dropwise over 20 mins and the mixture was stirred under nitrogen for a further 18 hours in the dark. The grey slurry was filtered and the solvent was removed from the filtrate under reduced pressure to give a grey solid. This crude material was then recrystallised from IPA to give a off-white solid (3.7 g, 36%). SH (500 MHz; CDCl 3 ) 3.03 (2H, s, —CH 2 —C(O)—O—), 7.24 (2H, d, J 8, Ph). & 7.69 (2H, d, J 8.5, Ph).
Example 6
Synthesis of Isoeuginol Diester of Succinic Acid
[0392] Isoeuginaol (25 g, 0.15 mol) was dissolved in THF (100 cm 3 ). Sodium carbonate (16.14 g, 0.15 mol) was added and the mixture stirred at room temperature. Succinyl chloride (11.8 g, 0.075 mol) was added to the stirred mixture over 20 minutes, and the mixture stirred for a further 90 minutes. The reaction mixture was then heated to 50° C. for 60 mins, then stirred at room temperature overnight. The mixture was filtered and the solvent removed under reduced pressure to give a dark coloured oil which solidified upon standing. This crude material was recrystallised from ethyl acetate and diethyl ether to give an off-white solid (4.67 g, 8%) δ H (500 MHz; CDCl 3 ) 1.86 (6H, d, —CN 3 —CH═CH—), 3.80 (6H, s, Ph CH 3 ), 6.34-6.14 (4H, m, CH═CHCH 3 ) and 6.70-6.88 (6H, m, Ph).
Example 7
Synthesis of Hexamethylene diisocyanate blocked with Meldrum's Acid
[0393] Synthesis:
[0394] At room temperature a mixture of diisocyanatohexane (5.0 mL, 30.92 mmol, 1 eq.) and Meldrum's acid (9.36 g, 64.92 mmol, 2.1 eq.) in dichloromethane (100 mL) was treated with triethylamine (12.9 mL, 92.75 mmol, 3.0 eq.) in a dropwise fashion. Stirring was continued for 15 hours. TLC analysis (EtOAc) indicated no remaining Meldrum's acid. Silica (ca. 25 g) was added and the solvent was removed in vacuo. Purification by flash column chromatography afforded the diamide (7.33 g, 55%) as a colourless solid. R f =0.1 (EtOAc); δ H (400 MHz, CDCl 3 ) 1.42-1.46 (4H, m, CH 2 ), 1.59-1.68 (4H, m, CH 2 ), 1.69-1.74 (12H, s(br), CH 3 ), 3.42 (4H, q, J 6.5 Hz, CH 2 ), 9.25-9.34 (2H, s(br), NH), 14.95-15.0 (2H, s(br), OH); δ C (100 MHz, CDCl 3 ) 26.2 (CH 2 ), 26.2 (CH 3 ), 28.9, 40.3 (CH 2 ), 72.8 (C-quat), 104.6, 164.2 (C═), 170.25, 170.3 (CO); m/z (ES+) 477 (M-H+2Na + , 100%); Found C, 51.49; H, 6.05; N, 5.98; C 18 H 28 N 2 O 10 requires C, 50.00; H, 6.48; N, 6.48.
Example 8
Synthesis of Hexamethylene diisocyanate blocked with Phenol
[0395] Synthesis:
[0396] Diisocyanatohexane (1.0 mL, 6.18 mmol, 1 eq.) and phenol (1.26 g, 13.39 mmol, 2.1 eq.) in dichloromethane (25 mL) was treated with triethylamine (2.7 mL, 19.37 mmol, 3.1 eq.) in a dropwise fashion. Stirring was continued for 15 hours.
[0397] The solvent was removed under reduced pressure and the solid obtained was dried in a vacuum desiccator. Thus, the title compound (2.16 g, 98%) was obtained as a white solid. δ H (400 MHz, CDCl 3 ) 1.36-1.44 (4H, m, CH 2 ), 1.54-1.65 (4H, m, CH 2 ), 3.26 (4H, q(br), J 6.5 Hz, CH 2 ), 5.05 (2H, m(br), NH), 7.12 (4H, d, J 7.5 Hz, ArH), 7.18 (2H, t, J 7.5 Hz, ArH), 7.34 (4H, t, J 7.5 Hz, ArH); δ C (100 MHz, CDCl 3 ) 26.2, 29.7, 41.0 (CH 2 ), 121.6 (CH), 125.2 (C-ipso), 129.2 (CH), 151.1 (C-ipso), 154.6 (CO); Found C, 66.00; H, 7.02; N, 8.27; C 20 H 24 N 2 O 4 requires C, 67.42; H, 6.74; N, 7.87.
Example 9
Synthesis of Hexamethylene diisocyanate blocked with Succinimide
[0398] Synthesis:
[0399] At room temperature a solution of diisocyanatohexane (7.57 g, 45.01 mmol, 1 eq.) and succinimide (8.90 g, 90.01 mmol, 2.0 eq.) in dichloromethane (100 mL) was treated with triethylamine (18.8 mL, 135.0 mmol, 3.0 eq.) in a dropwise fashion. Stirring was continued for 1 hour. The white precipitate formed was collected by filtration and washed with dichloromethane (3×50 mL) and dried in a vacuum desiccator. Thus, the title compound (14.93 g, 90%) was obtained as a white (colourless) powder. δ H (270 MHz, d 6 -DMSO) 1.12-1.45 (8H, m, CH 2 ), 2.64 (8H, s, CH 2 ), 3.01 (4H, q, J 6.5 Hz, CH 2 ), 9.25-9.34 (2H, t, J 6.5 Hz, NH); Found C, 52.28; H, 6.04; N, 15.30; C 16 H 22 N 4 O 6 requires C, 52.46; H, 6.01; N, 15.30.
Example 10
Synthesis of Hexamethylene diisocyanate blocked with Sodium Bisulphite
[0400] Synthesis:
[0401] In a 100 mL round-bottom flask containing a magnetic stirrer bar, hexamethylene diisocyanate (6.73 g, 0.04M) was added sodium metabisulphite (8.36 g, 0.044M) dissolved in 16 mL of water and the turbid solution covered and stirred for 17 hours at room temperature (20° C.). The product was precipitated in acetone (100 mL) filtered and dried. The product was dissolved in water (30 mL) then precipitated with acetone (350 mL), filtered and dried in vacuo, resulting in a fine white powder in 93% yield*.
[0402] FTIR confirmed the formation of CONH (1680 cm −1 ) and lack of an isocyante peak (2275 cm −1 ) indicated that no free diisocyanate was present.
[0403] *NMR assay (internal trioxan standard) confirmed a purity of 57.43%. The impurities probably are sodium metabisulphite. 1 H NMR-(D 2 O): δ (ppm) 1.36 (4H, m); 1.55 (water, s); 1.59 (4H, m); 2.23 (acetone, s); 3.29 (4H, t); 4.74 (D 2 O); 5.23 (trioxan, 6H, s)
Example 11
Synthesis of Hexamethylene diisocyanate blocked with 4-Nitrophenol
[0404] Synthesis:
[0405] Diisocyanatohexane (4.1 mL, 25.35 mmol, 1 eq.) and 4-nitrophenol (7.06 g, 50.75 mmol, 2.0 eq.) in dichloromethane (100 mL) was treated with triethylamine (7.1 mL, 50.75 mmol, 2.0 eq.) in a dropwise fashion. Stirring was continued for 2 hours. The yellowish precipitate formed was collected by filtration and washed with dichloromethane (2×50 mL), Et 2 O (1×50 mL) and dried in a vacuum desiccator. Thus, the title compound (11.25 g, 100%) was obtained as a white-yellow powder. δ H (400 MHz, d 6 -DMSO) 1.31-1.45 (4H, m, CH 2 ), 1.46-1.59 (4H, m, CH 2 ), 3.10 (4H, t(br), J 6.5 Hz, CH 2 ), 7.40 (4H, d, J 9.0 Hz, ArH), (2H, t(br), J 6.5 Hz, NH), 8.28 (4H, d, J 9.0 Hz, ArH); Found C, 52.28; H, 6.04; N, 15.30; C 16 H 22 N 4 O 6 requires C, 52.46; H, 6.01; N, 15.30.
Example 12
Synthesis of Hexamethylene diisocyanate blocked with 4-Methoxyphenol
[0406] Synthesis:
[0407] Diisocyanatohexane (3.5 mL, 21.58 mmol, 1 eq.) and 4-methoxyphenol (5.36 g, 43.17 mmol, 2.0 eq.) in dichloromethane (50 mL) was treated with triethylamine (9.0 mL, 64.76 mmol, 3.0 eq.) in a dropwise fashion. Stirring was continued for 15 hours. The white precipitate formed was collected by filtration and washed with dichloromethane (2×50 mL) and dried in a vacuum desiccator. Thus, the title compound (5.0 g, 59%) was obtained as a white powder. δ H (400 MHz, d 6 -DMSO) 1.25-1.42 (4H, m, CH 2 ), 1.45-1.55 (4H, m, CH 2 ), 3.07 (4H, q(br), J 6.0 Hz, CH 2 ), 3.36 (6H, S, CH 3 ), 6.90 (4H, d, J 9.0 Hz, ArH), 7.02 (4H, d, J 9.0 Hz, ArH), 7.61 (2H, t(br), J 6.0 Hz, NH); δ C (100 MHz, d 6 -DMSO) 26.3, 29.5, 40.7 (CH 2 ), 55.7 (CH 3 ), 114.5, 122.9 (CH), 144.9, 155.1 (C-ipso), 156.6 (CO); Found C, 62.58; H, 7.08; N, 7.66; C 20 H 28 N 2 O 6 requires C, 61.22; H, 7.14; N, 7.14.
Example 13
Synthesis of Hexamethylene Diisocyanate Blocked with Methyl Salicylate
[0408]
[0409] Diisocyanatohexane 1 (0.9 mL, 5.57 mmol, 1 eq.) and the phenol 2 (1.50 g, 10.38 mmol, 1.9 eq.) in dichloromethane (50 mL) was treated with triethylamine (2.3 mL, 16.69 mmol, 3.0 eq.) in a dropwise fashion. Stirring was continued for 15 hours. The solvent was removed under reduced pressure and the crude reaction mixture was purified by flash column chromatography (Hex-EtOAc; 2:1→1:1) affording the title compound (4) as a white (colourless) crystalline solid (0.725 g, 29%) was obtained as a white powder. R f =0.15 (Hex-EtOAc; 1:1); m/z (ES + ) 463 (MNa + , 100%);. δ H (250 MHz, CDCl 3 ) 1.32-1.95 (BH, m, CH 2 ), 3.23 (2H, q, J 6.5 Hz, CH 2 ), 3.82 (3H, s, CH 3 ), 4.02 (2H, t, J 7.0 Hz, CH 2 ), 5.29 (1H, m(br), NH), 7.12 (1H, d, J 7.5 Hz, ArH), 7.20-7.34 (3H, m, ArH), 7.51 (1H, dt, J 1.5, 7.5 Hz, ArH), 7.69 (1H, dt, J 1.5, 7.5 Hz, ArH), 7.96 (1H, dd, J 1.5, 7.5 Hz, ArH), 8.08 (1H, dd, J 1.5, 7.5 Hz, ArH); found C, 61.9; H, 5.5; N, 6.2%, C 23 H 24 O 7 N 2 requires C, 62.7; H, 5.45; N, 6.4%.
Application Examples
[0410] In the examples 14-19 and 27 given below, the synthesised esters were pad applied to oxford cotton fabric (18×6 cm) at 100% pick-up from solvent (e.g. THF and/or water). The fabric swatches were then dried, followed by an iron cure on high setting (cotton/linen) for the time specified.
[0411] After curing, the swatches were conditioned at 20° C., 65% relative humidity then the crease recovery angle (CRA) measured (using BS1553086). A sample of fabric (25 mm×50 mm) was folded in half forming a sharp crease and held under a weight of 1 kg for 1 minute. On releasing the sample the crease opens up to a certain degree. After 1 minute relaxation, time the angle is measured. The fabric is tested in the warp direction only (hence maximum CRA is 180°). Higher CRA therefore indicates less wrinkled fabric.
[0412] In examples 19-26 blocked isocyanates were pad applied to cotton fabric (18×6 cm) at 100% pick-up from an appropriate solvent. The fabric swatches were then dried, followed by an iron cure on high setting (cotton/linen) for the time specified.
[0413] After curing, the swatches were conditioned at 20° C., 65% relative humidity then the crease recovery angle (CRA) measured (using a modified method based on BS1553086). A sample of fabric (25 mm×50 mm) is folded in half forming a sharp crease and held under a weight of 1 kg for 1 minute. On releasing the sample the crease opens up to a certain degree. After 1 minute relaxation time the angle is measured. The fabric is tested in the warp direction only (hence maximum CRA is 180). Higher CRAs correspond to less wrinkled fabrics.
Example 14
Application of 2,4,6-Trichlorophenol Diester of Butanetetracarboxylic Acid
[0414] CRA results obtained with a 5% solution of diester in THF (1 g diester in 19 g THF) are shown in Table 1 below.
TABLE 1 CRA 10 s iron 20 s iron 30 s iron 60 s iron UT Control 79 — — — 5% Diester 92 99 98 103
[0415] From these results it can be seen that less creasing (higher CRA) was obtained with the treated samples than with the untreated samples (UT). It can also be seen that the effect of a longer ironing-time on treated swatches is to further improve the results for the crease test (which occurs after the ironing step).
Example 15
Application of 2,4,5-Trichlorophenol Diester of Succinic Acid
[0416] CRA results obtained with a 7.65% solution of diester in THF are given in Table 2 below:
TABLE 2 CRA 10 s iron 20 s iron 30 s iron 60 s iron UT Control 78 — — — 7.65% 92 99 102 113 Diester
[0417] From these results it can again be seen that less creasing (higher CRA) was obtained with the treated samples than with the untreated samples (UT), and that a longer curing step further improved the results.
Example 16
Application of N-Hydroxysuccinimide Diester of Succinic Acid
[0418] CRA results obtained with a 5.25% solution of diester in THF and water are given in Table 3 below:
TABLE 3 CRA 10 s iron 20 s iron 30 s iron 60 s iron UT Control 71 5.25% Diester 87 88 93 95 (THF) 5.25% Diester 93 95 92 92 (water)
[0419] From these results it can be seen that less creasing (higher CRA) was obtained with the treated samples (both from THF and water) than with the untreated samples (UT). A water carrier gives good results with both a short and long a short curing/ironing step.
Example 17
Application of Vanillin Diester of Succinic Acid
[0420] CRA results obtained with 6.55% Diester in THF (19 cm 3 ) initially, increasing amount of water added are given in Table 4 below:
TABLE 4 CRA - 60 s Iron UT Control 77 6.55% Diester in THF (no water added) 82 6.55% Diester in THF + 1 cm 3 H 2 O 86 6.55% Diester in THF + 2 cm 3 H 2 O 85 6.55% Diester in THF + 3 cm 3 H 2 O 88 6.55% Diester in THF + 5 cm 3 H 2 O 91
[0421] From these results it can be seen that less creasing (higher CRA) was obtained with the treated samples (both from THF and THF+water) than with the untreated samples (UT).
Example 18
Application of 4-Cyanophenol Diester of Succinic Acid
[0422] CRA results obtained with a 5.45% solution of diester in THF are given in Table 5 below:
TABLE 5 CRA - 60 s Iron UT Control 77 5.45% Diester 84
[0423] From these results it can be seen that less creasing (higher CRA) was obtained with the treated samples than with the untreated samples (UT).
Example 19
Application of Hexylene Diisocyanate Biuret Blocked with Diethyl Malonate
[0424] The structure of this molecule is shown below.
[0425] Hexylene diisocyanate biuret blocked with diethyl malonate (trade name BI7963 ex. Baxenden Chemicals Ltd) was obtained as a 70% solution in 1-methoxy-2-propanol and diluted in THF to give a 2% solution. Results are given in table 6 below
TABLE 6 CRA Results Ironing Time CRA UT control 76 Light iron (less than 2 s) 90 2 s 92 4 s 93 6 s 92 8 s 95 10 s 97
[0426] In the case of the treated samples, it can be seen that even a very brief period of ironing gives a marked improvement in crease recovery. It is believed that this is due to the cross-reaction of the material with cellulose. It is also believed that this is an example of one of the isocyanate reactions which gives a true ester rather than a carbamate on reaction with cellulose.
Example 20
Application of Hexamethylene diisocyanate blocked with Meldrum's Acid
[0427] Application was as described above from a 2% solution. Results are given in table 6 below. It can be seen that crease recovery angles were improved as compared with the control.
TABLE 6 CRA (2% solution in DCM) Ironing Time CRA UT Control 73 2 s 83 6 s 85 10 s 84 20 s 85
Example 21
Application of Hexamethylene diisocyanate blocked with Phenol
[0428] Application was as described above from a 2% solution. Results are given in table 7 below. It can be seen that crease recovery angles were improved as compared with the control.
TABLE 7 CRA (2% solution in THF) Ironing Time CRA UT Control 73 2 s 84 6 s 94 10 s 89 20 s 89
Example 22
Application of Hexamethylene Diisocyanate Blocked with Succinimide
[0429] Application was as described above from a 2% solution. Results are given in table 8 below. It can be seen that crease recovery angles were improved as compared with the control.
TABLE 8 CRA (2% solution in DMAc) Ironing Time CRA UT Control 73 2 s 94 6 s 98 10 s 99 20 s 102
Example 23
Application of Hexamethylene diisocyanate Blocked with Sodium Bisulphite
[0430] Application was as described above from a 1% solution. Results are given in table 9 below. It can be seen that crease recovery angles were improved as compared with the control.
TABLE 9 CRA (1% solution in water) Ironing Time CRA UT Control 75 2 s 78 6 s 83 10 s 85 20 s 85
Example 24
Application of Hexamethylene diisocyanate Blocked with 4-Nitrophenol
[0431] Application was as described above from a 2% solution. Results are given in table 10-below. It can be seen that crease recovery angles were improved as compared with the control.
TABLE 10 CRA (2% solution in DMAc) Ironing Time CRA UT Control 73 2 s 77 6 s 83 10 s 95 20 s 92
Example 25
Application of Hexamethylene diisocyanate blocked with 4-Methoxyphenol
[0432] Application was as described above from a 2% solution. Results are given in table 11 below. It can be seen that, other than for very short ironing times, crease recovery angles were improved as compared with the control.
TABLE 11 CRA (2% solution in DMAc) Ironing Time CRA UT Control 73 2 s 73 6 s 73 10 s 84 20 s 90
Example 26
Application of Hexamethylene diisocyanate Blocked with Methyl salyciliate
[0433] Application was as described above from a 2% solution. Results are given in table 12 below. It can be seen that crease recovery angles were improved as compared with the control.
TABLE 12 CRA (2% solution in THF) Ironing Time CRA UT Control 73 2 s 87 6 s 86 10 s 87 20 s 86
Example 27
Application of Isoeuginol Diester of Succinic Acid
[0434] Upon application of the isoeuginol diester to cotton and subsequent ironing, a clove fragrance was released as the trans-esterification crosslinking occurred. | A method of treating finished garments comprising cellulosic material so as to cause cross-linking, which comprises the step of treating fabrics with an effective amount of a blocked cross-linking agent for cellulose, said cross-linking agent being thermally activated. A composition for use in the said method which comprises an effective amount of a blocked cross-linking agent for cellulose, said cross-linking agent being thermally activated. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to a convenience structure for mounting and applying window frame moldings, and more specifically to provide users with a window molding system for framing a window covering which helps the user save time, it provides variety, and a more organized window molding system.
BACKGROUND OF THE INVENTION
[0002] Prior art structures for window frame moldings have been most rudimentary and disorganized, mostly consisting of a regular molding being nailed or glued around the perimeter of a window by an installer. Frame moldings utilized with window coverings are not purely for aesthetic purposes but are typically mounted about the periphery of a window opening and oriented to extend within the dimensions of the window opening to form a smaller opening to cover the light space between the outer edges of the window covering (typically horizontal blinds) and the window opening within which the window covering operates.
[0003] The provision of a window opening peripheral additional cover enables a typical horizontal blind window covering to operate much more efficiently in shutting out light in the closed position. Unwanted light which is eliminated includes light entering at the top of the channel support, sides of the channel supports, ends of the louvers and the ends and bottom of the base louver. Where the base louver either falls short of the bottom of the window opening or where the base louver is pivotally mounted by a hold down, significant light can enter at the base of the bottom louver. The window opening peripheral additional cover significantly contributes to light blockage at the bottom of the window covering.
[0004] Aside from both functionality and aesthetics the question of replacement is an important one. Replacement can be required due to damage or due to the desire for aesthetic change. Where conventional window opening peripheral additional cover is custom made and fitted into an opening replacement is not only expensive and burdensome, but can cause significant damage to the surrounding wall areas. As a result, replacement of conventionally installed window opening peripheral additional cover members will include a second custom installation as well as surrounding wall repair.
[0005] When the user desires to change or remove the molding because of color, style or damage to the molding, the wall segment around the window's perimeter will have nail holes, chipped wall board around the nail holes, and the existing nail holes cannot be re-used because of enlargement or damage to the material. Plus the removed molding will be ruined and most un-usable.
[0006] When removing window moldings which were installed using glue or glue like substances, wall areas may be left with glue residue and debris, meaning that the installer will now have to put extra effort into plastering, cleaning, and stripping the area before new window moldings can be used.
[0007] Most window moldings today are usually made out of wood, a material which is not very durable and cannot fully withstand many climate variations, temperatures, and everyday exposure to the elements. When typical window moldings remain in a normal setting such as a house, the window moldings can be easily ruined by everyday occurrences such as water damage, thermal cracking, wood rot, bowing and fracturing, children's abuse of the molding, chipped paint, and termites.
[0008] For a premises owner, or user, to replace the damaged window moldings with new ones, the user would have to destructively remove the damaged moldings (as described above), buy new moldings, have an installer install them or begin measuring and cutting them for a custom installation. This can be very costly and time consuming for the user.
[0009] Another impracticality of window moldings is, especially since moldings are usually made out of wood, that they are less durable and the cost of manufacture is much greater than manufacturing and molding plastic, metal, synthetic, and fiberglass materials.
[0010] Most window moldings are meant to be permanent fixtures around the window. This has a disadvantage in that the user can't easily change the color or style. If a user wishes to change the room colors by painting the room, and wants to match the moldings to the new paint, the moldings will look messy and unprofessional after being painted, especially if they cannot be removed to paint them throughly.
[0011] The ability to, in a organized and easy manner, change or remove window moldings is an advantage which is conventionally not available, or available at a reasonable cost.
[0012] What is therefore needed is a device or structure which can easily and affordably allow window moldings to be changed or removed in an organized manner. The device needs to be easy to use so it will be more convenient to use it. It needs to be easy to install and not messy so when the window molding is removed, users will not have to do a lot of preparation to install a different molding. The device needs to be simple and inexpensive, so the majority of the general public can afford it. The device needs to help in reducing the time and effort spent in removing, changing, and installing window moldings.
SUMMARY OF THE INVENTION
[0013] A window frame molding system with removeable and interchangeable moldings of the present invention provide an organizational system which can be used to install, change, and remove window frame moldings while not damaging the window frame itself.
[0014] The entire structure consists of mounting support members and finish members. The mounting members are typically four straight pieces of metal, plastic, synthetics, or wood, with the ends cut angularly at 45°, and which forms the mounting base of the structure. The finish members include typically eight pieces of metal, plastic, synthetics, or wood, four straight members and four corner members, to interfit as exterior molding members. Because of the variety of materials which can be used to make the window frame moldings, they are very inexpensive and easy to manufacture.
[0015] The window frame molding system is of simple construction and user-friendly. The system of mounting the molding pieces by placing the pieces on pegs and slide locking them into place with screws, is nearly foolproof, thus, users will not have a hard time using the window frame molding system. Plus, the way that the moldings slide-lock in to place is much easier than the usual conventional method of gluing or nailing the moldings into place around the window frame. Also, the slide lock method is not messy like the two conventional methods mentioned above.
[0016] Since the window frame molding system can be made out of many different types of material, such as, metal, synthetics, plastics, and wood, the window frame molding system should be rather inexpensive to manufacture. Also, all the materials which can be used in making the window frame molding system can be treated with sealants and preservers so they will not be damaged by rust, wood rot, or termites. Plus, since the window frame molding system is so inexpensive to produce, they can be manufactured in many different styles and patterns so the users will have more of a variety of window moldings to use, and will be able to change moldings when they change the molding surroundings such as, painting the room the window frame molding system is being used in.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The invention, its configuration, construction, and operation will be best further described in the following detailed description, taken in conjunction with the accompanying drawings in which:
[0018] [0018]FIG. 1 is an exploded perspective of a window frame molding system illustrating the components and their method of assembly;
[0019] [0019]FIG. 2 is a back view of the window frame molding showing the screws used to slide lock the molding into place, and the two peg blind bores in each corner;
[0020] [0020]FIG. 3 is a front view of the assembled window covering frame system but with non-closely conforming junction pieces, corner pieces in the case of a rectangular configuration, which extend slightly into the area within the frame opening;
[0021] [0021]FIG. 4 is a side sectional view taken along line 4 - 4 of FIG. 3 and illustrates the top portion of an unassembled view of a straight molding pieces about to enter a locked position with a mounting piece and locked into place with a junction piece;
[0022] [0022]FIG. 5 is a side sectional view in accord with FIG. 4 after locking and securing of the junction piece has taken place;
[0023] [0023]FIG. 6 is a side sectional view taken along line 6 - 6 of FIG. 1 and illustrating the close conformity between the exterior pattern of a straight molding and the underside and top side of a lip of a junction piece; and
[0024] [0024]FIG. 7 is an assembled version of the window frame molding system as seen in FIG. 1 in an assembled position and with respect to a horizontal blind mounted within it, but un-attached to any window opening or wall surrounding a window opening.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] A description of the inventive window frame molding system as shown in FIG. 1 as a window frame molding system 11 . FIG. 1 is an exploded overall view of the components of the system 11 , including mounting support members and finish members. The entire system 11 shown in FIG. 1 consists of sixteen major pieces in combination with keyhole reinforcements. The system shown contemplates a rectangular realization, however other geometrical shapes are possible with a corresponding increase in the number of parts.
[0026] The system 11 includes finish members including four junction pieces 13 , 15 , 17 , and 19 , four pieces of decorative molding 21 , 23 , 25 , and 27 . Junction pieces 13 , 15 , 17 , and 19 are shown as corner pieces where the window covering opening is rectangular. The junction pieces 13 , 15 , 17 , and 19 , occur at the corners, but there is no reason that they should not occur also along straight lengths of the decorative molding 21 , 23 , 25 , and 27 .
[0027] Further, there is no reason that the slide lock mechanism disclosed would not work at various places along the molding 21 , 23 , 25 , and 27 . In other words, the rectangular window opening shape may have its molding 21 , 23 , 25 , and 27 periodically interrupted with junction pieces 13 , 15 , 17 , and 19 not located at angled meetings of the molding 21 , 23 , 25 , and 27 but between straight sections. Further, for shapes other than rectangular, such as pentagonal, hexagonal and the like, the molding 21 , 23 , 25 , and 27 may be provided and over window openings of these shapes, especially where either the wall is built out to provide adequate operating space for a rectangular blind set or where the fully opened blind set matches the shape.
[0028] Behind the finish members 13 , 15 , 17 , 19 , 21 , 23 , 25 , and 27 are four pieces of straight mounting members 29 , 31 , 33 , and 35 . The straight mounting members 29 , 31 , 33 , and 35 are generally rectangular cross section, elongate stick shapes, but may end in forty-five degree angle tapers in order to form a sharp corner. The custom interfit of the ends of the straight mounting members 29 , 31 , 33 , and 35 would be done where it was desired to keep out the last measure of light.
[0029] The straight mounting members 29 , 31 , 33 , and 35 are preferably pre bored with a series of keyhole or slot depressions 37 . The slot depressions 37 are preferably covered by a keyhole plate 39 . The use of the keyhole plate relieves the need to seek materials which could provide a naturally formed keyhole opening, as well as the need to form a partially enclosed volume within a solid piece of material.
[0030] The slot depressions 37 are provided to enable good clearance for a bolt or screw head to enter through the keyhole plate 39 without interference from the material of the straight mounting members 29 , 31 , 33 , and 35 . Slot depressions 37 typically include a deep slot portion 41 and a keyhole plate 39 countersunk portion 43 to enable the keyhole plate 39 to fit at or beneath the external surface level of the straight mounting members 29 , 31 , 33 , and 35 .
[0031] The keyhole plate 39 typically has a pair of end apertures 45 for mounting with threaded apertures (not shown) into the material of the straight mounting members 29 , 31 , 33 , and 35 . Again, the area around the apertures 45 are appropriately lowered or countersunk so that the heads of the threaded members also lie below the outer surfaces of the straight mounting members 29 , 31 , 33 , and 35 .
[0032] Also note that the four junction pieces 13 , 15 , 17 , and 19 each have an overlapping lip 47 which continues a shape which generally conforms to the shape of the decorative molding 21 , 23 , 25 , and 27 . The overlap enables the pattern to be semi-continuous although the lip can be seen to overlap a portion of the pattern at the end of the decorative molding 21 , 23 , 25 , and 27 . This has the advantage that a relatively rough cut end of the decorative molding 21 , 23 , 25 , and 27 is well covered by the lip 47 and will not show. The disadvantage is that the discontinuity is more apparent than it would otherwise be in a custom frame.
[0033] In terms of overall utility, the slot depressions 37 and their associated keyhole plates 39 will be located at an even spacing along the length of one or more of the side surfaces of the straight mounting members 29 , 31 , 33 , and 35 . As can be seen, the straight mounting members 29 , 31 , 33 , and 35 have a somewhat rectangular cross section. The mounting methodology for the straight mounting members 29 , 31 , 33 , and 35 can include mounting about the outside periphery of a window opening or mounting about the inside periphery of a window opening. The method of attachment of the straight mounting members 29 , 31 , 33 , and 35 is preferably by any means and includes gluing, nailing, and the like. Regardless, the best stability is had by mounting one of the relatively wider sides against the wall surface to which they are to be attached. For mounting on the outside of the window opening, the four pieces of decorative molding 21 , 23 , 25 , and 27 will fit into slot depressions 37 and their associated keyhole plates 39 on the opposite, relatively wider surface of the straight mounting members 29 , 31 , 33 , and 35 , as is seen in FIG. 1.
[0034] However for mounting on the inside, inner periphery of a window opening, the four pieces of decorative molding 21 , 23 , 25 , and 27 will fit into slot depressions 37 and their associated keyhole plates 39 on the adjacent, relatively wider surface of the straight mounting members 29 , 31 , 33 , and 35 .
[0035] As a result, the four pieces of decorative molding 21 , 23 , 25 , and 27 preferably come with the slot depressions 37 and their associated keyhole plates 39 pre-formed on two adjacent sides, as is seen in FIG. 1. Further, the spacing of the slot depressions 37 and their associated keyhole plates 39 is an even spacing, and no regard need be given (although it can be in some exacting cases) to the exact positioning of the slot depressions 37 and their associated keyhole plates 39 along the straight mounting members 29 , 31 , 33 , and 35 .
[0036] In the case of a rectangular window opening as is the case in FIG. 1, once the four pieces of straight mounting members 29 , 31 , 33 , and 35 are cut and positioned with regard to a window opening, the four pieces of decorative molding 21 , 23 , 25 , and 27 can be fitted (as will be shown) with the excess then cut off to yield a system which is specific to the installed straight mounting members 29 , 31 , 33 , and 35 .
[0037] Also seen in FIG. 1 are a series of brackets 51 which are shown at the corners or angles of the system 11 , although not required to be placed at the corners or angles. Brackets 51 are typically found at the angular meeting points of the mounting pieces 29 , 31 , 33 , 35 , although brackets 51 could be placed along the main length of mounting pieces 29 , 31 , 33 , 35 to hold many such junction pieces 13 , 15 , 17 , and 19 where punctuation of the molding 21 , 23 , 25 , and 27 with junction pieces 13 , 15 , 17 , and 19 is desired.
[0038] Brackets 51 are preferably made of thin metal with a pair of polymeric projections 53 and a series of attachment apertures 55 . The polymeric projections 53 engage and hold junction pieces 13 , 15 , 17 , and 19 by means of a generally matched rear bore in the back sides of the junction pieces 13 , 15 , 17 , and 19 . The polymeric projections 53 may preferably be made of deformable material in order to have a better hold. A circular shape with ribs to concentrate the deformation is shown in FIG. 1. The downward angled ribs give a preferred deformation upon insertion and more force upon removal to insure a good lock.
[0039] The brackets 51 perform two important functions. By being attached with apertures 55 to the straight mounting members 29 , 31 , 33 , and 35 , they are thus strengthened by mutual force support. In other words, once the brackets 51 are added, the straight mounting members 29 , 31 , 33 , and 35 have the strength of a mounted stiff frame rather than the individual strengths of the members.
[0040] Secondly, the brackets 51 have a width approximately equal to the narrowest width of the straight mounting members 29 , 31 , 33 , and 35 and are thus easily located and positioned at the exact corners. It is not necessary for two straight mounting members 29 , 31 , 33 , and 35 to abut or meet exactly at a corner. An overlap of one member over the other is acceptable. A gap is also acceptable. The brackets 51 have sufficient strength to lend the proper stability to the resulting frame.
[0041] The lengths of decorative molding 21 , 23 , 25 , and 27 may have a series of pre-inserted threaded members having heads for engaging the deep slot portion 41 and a keyhole plate 39 . The series of pre-inserted threaded members (not shown in FIG. 1) should have the same spacing as the series of pre-inserted threaded members. When this is the case, and once the mounting members 29 , 31 , 33 , and 35 are in place, the lengths of decorative molding 21 , 23 , 25 , and 27 may be fitted in place and have the excess end material removed. Some test interfitting may be required so that a particular one of the lengths of decorative molding 21 , 23 , 25 , and 27 can be matched with a single one of the mounting members 29 , 31 , 33 , and 35 which will give the most advantageous elimination of scrap or even of cutting.
[0042] Savings in cutting may occur where identified non cut ends of the lengths of decorative molding 21 , 23 , 25 , and 27 are coordinated with an identified end of one of the mounting members 29 , 31 , 33 , and 35 with cutting indicated to occur on the other end of the mounting members 29 , 31 , 33 , and 35 , such that cutting of the molding 21 , 23 , 25 , and 27 can be made to occur on one end only. This technique can reduce cutting to one cut per piece, both for the mounting members 29 , 31 , 33 , and 35 , as well as the molding 21 , 23 , 25 , and 27 .
[0043] An optional corner cut 57 with implaced pegs 59 illustrates a variation where corners may be moved precisely together and where pegs 59 may be utilized. In this case it is better to pre manufacture the corner cut 57 and pegs 59 to indicated them as being the ends of the mounting members 29 , 31 , 33 , and 35 which are restrained from cutting. If such a mixed system is utilized, the two opposite corners should be corner cut 57 with pre-inserted pegs 59 and possibly marked to indicate that no cutting should occur. This would leave only two brackets 51 to be installed. In the alternative, all four corners may have brackets 51 and the ends of the mounting members 29 , 31 , 33 , and 35 could still be marked for non cutting and for fitting abutment into the window opening.
[0044] The system 11 in FIG. 2 shows a rear view of the constructed moldings and including a first view of a series of a series of evenly spaced slide-lock screws 61 . Note that the slide-lock screws 61 begin at a given spacing from one end of each of the molding lengths 21 , 23 , 25 , & 27 , and appear not to be symmetrical along their lengths. The slide-lock screws 61 are preferably machine inserted at the factory to insure that they will correspond to the placement of the keyhole plates 39 . Since boring and chamfering accompanied the placement of the keyhole plates 39 , any mis-alignment could be quickly remedied by re-positioning of the slide-lock screws 61 . Further, the insertion of the slide-lock screws 61 should be of an exact depth to enable operation with the keyhole plates 39 without further adjustment, although such further adjustment could be easily had with a few degrees of turn with a screwdriver.
[0045] Also seen are a pair of blind bores 62 which are arranged in somewhat of a forty five degree orientation as a line between them. The positioning of the blind bores 62 corresponds with the positioning of the polymeric projections 53 . In the case of the corner cut 57 ends, the pre-inserted pegs 59 are pre-positioned to interfit with the blind bores 62 . In either case, the blind bore 62 positioning causes a positive lock to be transmitted back from the mounting pieces 29 , 31 , 33 , 35 .
[0046] Referring to FIG. 3, a variation on the junction pieces 13 , 15 , 17 , and 19 are seen as junction pieces 63 , 65 , 67 , and 69 where these junction pieces have a lip having an underside surface which does not conform to the overall pattern of the molding 21 , 23 , 25 , and 27 . However since the upper surface of the lip is a generally flat pattern dominated by the surface pattern of the junction pieces 63 , 65 , 67 , and 69 there is sufficient material to enable a clearance to the rear to overlap the molding pattern.
[0047] In FIG. 3 the overall motif is such that the corner patterns project such that it is clear that the frame is not one piece, but the overlap appears more deliberate and the corners dominate the pattern. The view of FIG. 3 emphasizes that the patterns can be mixed and matched to produce more dramatic effect.
[0048] Referring to FIG. 4, side sectional view taken along only the upper portion of section line 4 - 4 shows the cross section of the interfit. The top straight mounting piece 31 is shown as coming completely through and atop the side straight mounting piece 33 , to illustrate one possible manner of fit. To the left of mounting pieces 33 and 31 is seen the bracket 51 and its leftwardly extending polymeric projections 53 . A pair of threaded members 71 are shown securing the bracket 51 into the mounting pieces 31 and 33 .
[0049] To the left, decorative molding 25 is seen as having a slide screw 61 protruding a sufficient amount to enter through the large end of the keyhole plate 39 resting in the countersunk portion 43 such that the head of the slide screw 61 enters the slot depression 37 . The dashed arrow gives the direction of entrance and translation of the head of the slid screw 61 as it moves toward the terminal end of the slot depression 37 and into a locked position.
[0050] In terms of locking, friction locking or narrowed locking is not necessary as the implacement of the junction piece 65 will prevent the slide screw 61 from reversing its path within the slot depression 37 . Thus, so long as the junction piece 65 is located at the end of a molding 25 which moved away from that corner in order to lock into place, it cannot reverse its path to become unlocked. Also seen in FIG. 5 is a lip 73 on the junction piece 65 .
[0051] This is illustrated in FIG. 5 with a view of both the top and bottom portions. The molding 25 has to be moved up in order to free it from the mounting piece 33 .
[0052] Referring to FIG. 6, an assembled view taken along line 6 - 6 of FIG. 1 illustrates how the lip 47 overlies the top surface of the molding 23 . It also shows how the lip 47 has an underside and a top side which generally conforms to the details of the outer surface of the pattern on the molding 23 .
[0053] The polymeric projections 53 preferably has a series of side engagement ridges which have a good hold on the junction piece 65 . A first set of decorative moldings 21 , 23 , 25 , and 27 can be removed by simply removing the junction pieces 63 , 65 , 67 and 69 , moving the decorative molding 21 , 23 , 25 , and 27 to unlock position and putting them away. A second set of decorative molding 21 , 23 , 25 , and 27 can be purchased, fitted, marked, and cut to fit in the same manner as the first set of decorative molding 21 , 23 , 25 , and 27 . Optionally, a second set of junction pieces 13 , 15 , 17 , and 19 or junction pieces 63 , 65 , 67 , and 69 are instantly interchangeable. So, not only can the junction pieces 13 , 15 , 17 , and 19 and junction pieces 63 , 65 , 67 , and 69 and the decorative molding 21 , 23 , 25 , and 27 be changed, either can be changed separately to create mix and match combinations.
[0054] Referring to FIG. 7, an assembled version of the window frame molding system 11 of FIG. 1 is seen in an assembled position and with respect to a horizontal blind mounted within it, but un-attached to any window opening or wall surrounding a window opening. Window frame molding system 11 is shown with respect to a horizontal blind set 77 mounted behind the system 11 , but with no other details of attachment for the blinds which would typically be attached to a ceiling or rear window surface. Further, to show the possibilities, in this case the vertical straight mounting pieces 29 and 33 extend the full vertical length while the top mounting piece 31 and bottom mounting piece 35 (not seen in FIG. 7) abut the vertical straight mounting pieces 29 and 33 . This illustrates that the straight mounting pieces 29 , 31 , 33 , and 35 can have any orientation at the corners especially since the brackets 51 are strong and provide adequate holding.
[0055] Also as can be seen in FIG. 7 the outer peripheral surfaces of the straight mounting pieces 29 , 31 , 33 , 35 could be applied to a peripherally inwardly set of wall surfaces just within a window opening wall space. The surfaces of both the straight mounting pieces 29 , and 31 seen would directly abut the inwardly directed wall surfaces.
[0056] Conversely, the rear surfaces of straight mounting pieces 29 , 31 , 33 , & 35 could be applied to the facing wall structure surrounding a window opening. In this case, the surfaces of both the straight mounting pieces 29 and 31 , for example. Would extend out from the wall and still be seen as would the side edges of the junction pieces 13 , 15 , 17 , and 19 and the side edges of the decorative molding 21 , 23 , 25 , and 27 would be viewable. In this case the user may provide other covering material for aesthetic purposes. However, regardless of the mounting, it can readily be seen that any top, side and bottom gap which would exist between the horizontal blind set 77 and adjacent wall surface is eliminated. The closer the horizontal blind 77 is mounted to the system 11 , the better job system 11 can do in shutting out unwanted peripheral light.
[0057] Although the invention has been derived with reference to particular illustrative embodiments thereof, many changes and modifications of the invention may become apparent to those skilled in the art without departing from the spirit and scope of the invention. Therefore, included within the patent warranted hereon are all such changes and modifications as may reasonably and properly be included within the scope of this contribution to the art. | A window frame molding system with removeable and interchangeable moldings of the present invention provide an organizational system which can be used to install, change, and remove window frame moldings while not damaging the window frame itself. For a rectangular installation, the entire structure can consist of four straight pieces of metal, plastic, synthetics, or wood, as mounting members, with the ends either flat or cut angularly at 45°, as the base of the structure. Further, four decorative moldings and four junction pieces of metal, plastic, synthetics, or wood, interfit with the mounting member in a configuration with the moldings being slide locked into place and the junction pieces securing the decorative moldings in place. Because of the variety of materials which can be used to make the window frame moldings, they are both inexpensive and easy to manufacture. | 4 |
BACKGROUND OF THE INVENTION
This invention relates primarily to oilfield pipelines, although it is not limited to this particular field. Most oilfield pipelines employ tubular members constructed of steel and are known as seamless pressure tubing, line pipe, or standard tubing. There are many different ways in which the tubular members are joined to one another to effect a continuous fluid conducting pipeline of limitless length.
it is common to join tubular members by threadedly connecting the ends together by employment of tapered threaded connections which rely upon friction for a sealed fit. Repeated expansion and contraction of the pipeline has a deleterious effect upon this method of construction and ultimately causes the threads to stretch until leakage occurs at the threaded connections.
For this reason, there is another widely used method of connecting tubular members together by the joining of two beveled opposed ends of pipe joints in a butt welded manner. However, the cost of labor and equipment required for this method is enormous.
Still others have proposed joining lengths of steel tubular goods together by a number of different means, including the employment of grooved ends having gaskets and bolted couplers; the use of crimping tools; the application of interlocking tabs; as well as the use of o-rings and compression rings.
For example, Veitch, U.S. Pat. No. 2,498,831 connects plastic pipe together with a coupling member, and uses an adhesive as a sealing means between the marginal pipe end and the coupling member.
Reesor, U.S. Pat. No. 3,343,252 joins conduit together by employment of a knurling process with an interlocking crimping process.
Curtin, U.S. Pat. No. 3,971,574 teaches that plastic pipe may be joined with a smooth fitted coupler, and includes an outside locking coupler.
Kyle et al U.S. Pat. Nos. 1,919,734; Carter 4,014,568, Bartholomew 3,997,195; Streit 4,002,358; Lowe 4,026,584; Asano 4,043,574; Martinez 4,076,285; Ramm 3,633,943; McGuire 3,701,548; Bingham 3,807,776; Frey 4,067,534; Wise 3,843,169; Garrett 3,565,468; and Singer 2,967,067 are other examples of the multitude of approaches to the problem of forming a continuous fluid conveying conduit from a plurality of pipe joints.
The present invention constitutes a step forward over the above prior art by providing a fast, reliable, and inexpensive method and apparatus by which tubular goods are connected together into a continuous fluid conveying pipeline. SUMMARY OF THE INVENTION
This invention relates to pipeline construction, and specifically to a method of joining pipe joints to a pipe connector or sleeve to provide a new and unusual pipeline. A pair of pipe joints are arranged in spaced relationship respective to one another. The sleeve which joins the marginal ends of the adjacent pipe joints has a pipe receiving socket formed in the opposed marginal ends thereof.
Each socket of the sleeve is divided into a smooth pipe receiving portion and a grooved pipe receiving portion. The adjacent marginal ends of the pipe joints are forced through the smooth and grooved portions of the sockets, and towards one another, as the grooves deform the metal on the outer peripheral wall surface of the marginal ends of the pipe joints, thereby providing a strong mechanical connection.
In the preferred embodiment of the invention, the grooves are located externally of the smooth bore, and the smooth bore receives the marginal terminal end of a pipe joint with a friction fit. A sealant, such as epoxy resin, for example, is applied to the interface between the marginal end of the pipe joint and the interior wall surface which forms the socket. As the adjacent pipe ends are forced into the sockets of a sleeve, the pipe is twisted respective to the sleeve, or rotated about the longitudinal axial centerline thereof, thereby more evenly distributing the sealant and more firmly setting the grooves of the sleeve into the outer surface of the pipe joint.
Accordingly, a primary object of the present invention is the provision of a method by which pipe joints are joined together in the field by axially moving a pair of pipe joints towards one another and into a sleeve which frictionally engages the marginal ends of the pipe joints.
Another object of the present invention is the provision of a method of connecting adjacent ends of a pipe joint by frictionally engaging the marginal ends of the pipe within a sleeve.
A further object of this invention is the provision of a method and apparatus by which pipe joints are joined together by forcing the marginal ends thereof into a sleeve, where a sealant and high friction forces hold the pipe joints within the sleeve.
A still further object of this invention is the provision of a method of connecting the marginal ends of pipe joints together by forming a socket on one marginal end of a pipe joint and forcing another pipe end into the socket so that the pipe joints are held together by friction.
These and various other objects and advantages of the invention will become readily apparent to those skilled in the art upon reading the following detailed description and claims and by referring to the accompanying drawings.
The above objects are attained in accordance with the present invention by the provision of a method for use with apparatus fabricated in a manner substantially as described in the above abstract and summary.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a pipeline undergoing fabrication;
FIG. 2 is a disassembled, enlarged, fragmented, cross-sectional view of part of the apparatus disclosed in FIG. 1;
FIG. 3 is an enlarged, fragmented, cross-sectional view of part of the apparatus disclosed in FIG. 2;
FIG. 4 is an enlarged, fragmented, cross-sectional view of part of the apparatus disclosed in FIG. 3; and,
FIG. 5 is a part cross-sectional view of an alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 of the drawing discloses a pipeline 10 undergoing fabrication. The pipeline is comprised of seamless joints of pipe 12 arranged in series relationship respective to one another, with the adjacent facing marginal ends thereof being joined together by a coupling member 14, hereinafter called a sleeve.
Apparatus 16, which can take on several different forms, engages adjacent pipe joints at 18 and 20 and forces the adjacent joints toward one another and into the sleeve 14, as will be described in greater detail later on in this disclosure.
The apparatus 16 includes slips 19 and 22 which engage the outer peripheral surface of the pipe joint with great force, so that member 20 can be moved toward member 18 with great force, usually by employment of hydraulically actuated cylinders and the like. Chain drive apparatus 24 rotates slip member 22 respective to slip member 19 as members 18 and 20 are moved relative to one another, thereby rotating one pipe joint respective to an adjacent joint as the joints are being made up.
FIG. 2 discloses in greater detail the before mentioned coupling member 14, made in accordance with the present invention. As illustrated, coupling member 14 has already been joined to the marginal end of pipe joint 12', while pipe joint 12 is yet to be joined to the coupling member.
The sleeve 14 includes outwardly opening sockets which terminate at each end 26 and 28 thereof. A marginal length of the socket is grooved as indicated by the arrow at numeral 30. The grooves preferably are continuous and are comprised of a multiplicity of spaced apart circumferentially extending endless grooves, although the groove can have a beginning and an end which extends from end 26 into proximity of shoulder 32. The grooves 30 constitute a first diameter portion of the socket. A marginal length 34 of the socket is smooth and of constant diameter, and extends from grooves 30 to the reduced diameter portion 36 of the sleeve. Shoulder 38 is formed between diameters 34 and 36.
The terminal ends of each pipe joint are beveled as noted by the arrow at numeral 40. The pipe usually is beveled during fabrication of the individual joints.
As illustrated in FIG. 4, together with the other figures of the drawings, the circumferentially extending grooves 30 are comprised of a plurality of spaced apart, individual, circumferentially extending cutter blades 42. The marginal ends 56 of the blades are embedded into the outer pipe surface, with the remainder of the cutters forming a plurality of annular areas 44 which may contain a sealant 46, such as epoxy resin, G. E. Silicone Sealer; Loctite #RC680,620, and 601; retaining compounds; Loctite Super Bonder #495,416,430; and the like.
The cutting surface of the individual cutter blades of the groove engage the outer peripheral surface of the pipe and deforms the metal thereof in the manner illustrated at 48 and 50 in FIG. 4. This arrangement of the individual blades which form the grooves require a relatively small force for inserting the pipe end into the socket as compared to the greater force required to withdraw the pipe from the socket. The individual blades include an inclined surface 52 and vertical surface 54 arranged such that the cutting edge of the groove is directed towards the medial portion 36 of the sleeve so as to achieve the above action. The cutting edge 56 of the blades is embedded in the outer pipe surface in the illustrated manner.
In FIG. 3, together with FIG. 4, d1 indicates the outside diameter of the pipe 12, while d2 illustrates the diameter of the smooth bore portion of the socket. The last two diameters are essentially equal to one another so that a tight friction fit is required to force the pipe end into the smooth bore part of the socket. D3 is the diameter measured at the bottom of the grooves, while d4 is the diameter measured across the cutting blades. D4 is smaller than d1 so that the blade 56 is embedded into the surface of the pipe, as seen at 48 and 50, when the sleeve is forced to receive the pipe end.
FIG. 5 illustrates another form of the invention wherein one end of a pipe 112 has a coupling member 114 formed integrally thereon. This can be accomplished by welding a cylindrical member 114 thereon before internal coating of the pipe, or alternatively, by expanding the marginal end 114 of the pipe to provide a female cavity 64 which can subsequently be machined into the illustrated socket. Numerals 30 and 34 illustrate the grooved and smooth internal marginal walls of the socket, as in FIG. 2. Numeral 62 indicates the end of socket 64.
The pipe outwardly curves at 66 from diameter 68 to diameter 114 of the socket. Numeral 70 is the end of another pipe joint 112' which likewise has a socket 114 formed at the other end thereof so that the joints of pipe can be series connected together.
In operation, the pipe ends preferably are painted with sealant, such as epoxy resin or a similar cement, and placed within the slips 19 and 22 of hydraulic coupler apparatus 16. Slip 20 is moved towards slip 18 with the sleeve 14 being held in axial alignment therewith. At the same time, slip 22 is rotated respective to slip 19 so that as the marginal pipe ends are received within the opposed sockets of the sleeve, one pipe is twisted approximately 360° respective to the other pipe. This action distributes the sealant in an optimum manner about the coacting surfaces between the pipe and the sleeve, and at the same time facilitates movement of the pipe surface across the grooves 30. The slips at 20 are moved along track 25 until the pipe ends each abut the opposed shoulders 38 of the sleeve.
After the pipe ends have been joined to the sleeve, the resultant pipeline will withstand the bursting strength of the pipe without failure of the connection provided by the sleeve.
The pipe 12 can be standard seamless beveled steel tubular pipe. The sleeve 14 can be fabricated from the next suitable larger size of similar pipe, or alternatively, can be machined from a forging or a casting.
The grooved portion 30 of the socket preferably is slightly tapered so that the inner cutter blades are embedded deeper into the pipe surface as compared to the outer cutter blades.
The present invention avoids the use of mechanical seals, welding, or clamping, and provides a quick and economical means by which joints of a fluid conductor can readily be connected to provide a flow line of any desired length. There is no decision to make regarding which end of the pipe connects to which end of the sleeve because both of the sockets of the sleeve are identical and both of the pipe ends are indentical to one another. There is no high cost involved in preparing the pipe for attachment to the sleeve. The sleeve requires no field preparation or attachments or accessories. The sleeve may be machined from a piece of standard steel tubular pipe with the size being dependent upon the size of the pipe to be joined together.
The grooved portion 30 of the socket preferably comprises a plurality of spaced apart annular cutting surfaces which are continuous for 360°, with the cutting blade being radially disposed inwardly toward the longitudinal center line of the sleeve. The cutting blades are directed inwardly towards one another and the center of the sleeve so that the pipe end more easily is forced into the socket as compared to the forces required for withdrawal of the pipe end from the socket.
The relative diameter d1, d2 can be selected depending upon the bursting strength of the pipe or the anticipated maximum fluid pressures flowing through the pipe line. The smooth bore d2 of the sleeve can be made slightly smaller respective to d1 so that a tremendous friction fit is developed therebetween, or alternatively, can be made slightly larger for ease in fitting one within the other. In a 2 inch seamless tubing, the cutting blades preferably extend outwardly into the pipe surface as seen at 56 in FIG. 4, 10,000 to 30,000ths of an inch, with the blades being spaced about 1/8th inch apart.
As the sleeve is mated to the pipe with a twisting motion, a bond is formed between the pipe joint and the steel coupling sleeve that is greater than the bursting strength of the pipe walls. The present invention is particularly adapted for the joining together of steel tubular members which have previously been internally coated with plastic and the like because none of the coated area is affected with the joining process, and the resultant pipe line therefore has a continuous uninterrupted, undamaged coating. This is especially advantageous where the tubular members have been coated with plastic as seen, for example, in my previous U.S. Pat. No. 4,089,998.
The sleeve 14 can be attached to one joint of pipe 12 prior to shipment to the job site if desired. Moreover, as seen in FIG. 5, it is possible to upset one end 114 of the pipe into a sufficiently large diameter to enable the subsequent formation of a socket 34, 64 therewithin, thereby eliminating the separate sleeve altogether, and providing a unique means by which pipe ends can be joined together by following the teachings of the present invention. | Method and apparatus by which joints of seamless pipe are rapidly and economically fabricated into a fluid conveying pipeline. Steel tubular fluid conducting members in the form of pipe joints are joined together by a steel coupler sleeve. The sleeve has opposed cavities which receive adjacent marginal ends of the members. Each marginal end of the pipe is forced into one cavity of the sleeve with great force such that the sleeve cavity holds the pipe ends together with a strong friction fit. A sealing substance is applied to the marginal ends of the pipe. A special hydraulic machine engages and forces the marginal ends of the pipe into the sleeve cavities with a twisting motion, which enhances the connection effected between the sleeve and the marginal end of the pipe. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority based on European patent application EP 15 193 390.0 filed Nov. 6, 2015. The entire disclosure and contents of this application is incorporated by reference into the present application.
FIELD
[0002] The present invention relates to a needle board, and more particularly, to a needle board for use in a needling machine for needling a flat textile material such as a nonwoven, a woven fabric or a laid material.
BACKGROUND
[0003] When flat textile materials are needled, especially nonwovens, it is desirable to achieve the most uniform possible needling without the formation of patterns in the flat textile material.
[0004] It has been found advantageous for this purpose for rows of needles to be arranged in a herringbone pattern and not simply to extend in rows and columns in the longitudinal and transverse directions of the needle board. Nevertheless, stripes or patternings still occur in the needled flat textile material, especially at high feed-per-stroke ratios.
[0005] It is an object of the present invention to provide a needle board for use in a needling machine for needling a flat textile material of which a uniformly needled flat textile material is obtained even at high feed-per-stroke ratios or over a wider feed range of the needling machine.
SUMMARY
[0006] According to an aspect of the invention, the needle board for use in a needling machine for needling a flat textile material comprises first needle rows and second needle rows, wherein the first needle rows and the second needle rows are arranged inclined with respect to a longitudinal direction of the needle board, which longitudinal direction corresponds to a direction in which the flat textile material to be needled is conveyed in the needling machine. The first needle rows are arranged at a first angle to the longitudinal direction, wherein the second needle rows are arranged at a second angle to the longitudinal direction. An absolute value of the second angle is different from an absolute value of the first angle.
[0007] Through variation of the absolute values of the angles and the nonuniform distribution of the needles in the needle board thus achieved, the formation of patternings in the needled flat material can be prevented even at high conveying speeds of the flat textile material through the needling machine in the great majority of cases. This is highly preferable.
[0008] Preferably, the first needle rows are arranged in a first block, and the first needle rows of the first block are parallel to each other. Further, preferably the second needle rows are arranged in a second block, wherein the second needle rows of the second block are parallel to each other.
[0009] It is also preferable to promote the further homogenization of the stitching pattern in the needled flat textile material, the needle board comprises a plurality of first blocks and a plurality of second blocks, wherein the first blocks and the second blocks are arranged to form a herringbone pattern.
[0010] An especially homogeneous stitching pattern is preferably obtained when the first needle rows and the second needle rows are arranged in such a way that a first projection of the first needle rows and of the second needle rows in or opposite to the longitudinal direction of the needle board yields at least certain sections in a transverse direction of the needle board, the transverse direction being perpendicular to the longitudinal direction of the needle board, in which sections transverse distances between first individual needle projections are equal.
[0011] It is highly preferred that to obtain a satisfactory stitching density, the transverse distances between the first individual needle projections are in the range of 0.05-2.5 mm, preferably of 0.1-1.5 mm, and more preferably of 0.2-1.0 mm.
[0012] Furthermore, preferably the first needle rows and the second needle rows are arranged in such a way that a second projection of the first needle rows and of the second needle rows in a transverse direction of the needle board, the transverse direction being perpendicular to the longitudinal direction of the needle board, yields at least certain sections in the longitudinal direction of the needle board, where longitudinal distances between second individual needle projections are different.
[0013] Preferably, when the needles in all of the first and second needle rows are spaced equally apart, this result is obtained automatically, thanks to the different absolute values selected for the first and second angles of the needle rows to the longitudinal direction of the needle board. All of the needle rows of a block of needle rows are usually arranged next to each other in such a way that the same needles of each needle row, i.e., all of the needles in the first position, all of the needles in the second position etc., together form a line extending in the transverse direction. From this follows in turn that the transverse projections of the needles within a block of needle rows comprise the same longitudinal distances from each other.
[0014] The transverse projections of the needles within a first block of first needle rows comprise first longitudinal distances from each other in the range of 0.5-20 mm, preferably of 1.0-15 mm, and more preferably of 2.0-5.0 mm.
[0015] The transverse projections of the needles within a second block of second needle rows comprise second longitudinal distances to each other in the range of 0.3-15 mm, preferably of 0.7-10 mm, and more preferably of 1.5-4.0 mm.
[0016] It has been found to be especially preferable for the absolute value of the first angle of the first needle rows to the longitudinal direction of the needle board to be in the range of 10-30°, preferably of 15-25°, and more preferably of 17-23°.
[0017] It has also been found preferable and advantageous for the absolute value of the second angle of the second needle rows to the longitudinal direction of the needle board to be in the range of 25-65°, preferably of 30-60°, and more preferably of 42-48°.
[0018] A needle row usually preferably comprises 5-40 needles. In a preferred embodiment, the needles of each needle row are connected to each other and thus form a needle module, which is arranged in a slot in the needle board.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The invention is explained in greater detail below with reference to the embodiments illustrated in the drawings:
[0020] FIG. 1 is a top view of part of an embodiment of a needle board according to the invention; and
[0021] FIG. 2 is a top view of the detail marked “X” in FIG. 1 .
DETAILED DESCRIPTION
[0022] FIG. 1 shows a top view of an embodiment of the needle board according to the invention. The individual needles 2 of the needle board are arranged in first needle rows 6 and second needle rows 7 and are indicated in this top view ( FIG. 1 ) as dots. The tips of these needles 2 project into the plane of the drawing beyond the base body 4 of the needle board. In the embodiment shown, each first or second needle row 6 , 7 comprises approximately 20 needles. A needle row 6 , 7 usually comprises between 5 and 40 needles.
[0023] The expert is familiar with many different possible ways in which needles 2 can be attached to base body 4 of the needle board. These ways include in particular the insertion of individual needles 2 into individual bores in base body 4 of the needle board. It is also possible, as shown in FIG. 1 , for individual needles 2 of a first or second needle row 6 , 7 to be connected to each other to form a needle module 8 , which in turn is inserted as a unit into a slot 10 in base body 4 of the needle board. First and second needle rows 6 , 7 are formed in both of these cases.
[0024] First and second needle rows 6 , 7 are preferably arranged in first and second blocks 12 , 13 . Needle rows 6 , 7 are in turn arranged to form a herringbone pattern extending in the longitudinal direction L of the needle board. This is understood to mean an arrangement in which needle rows 6 , 7 are arranged inclined with respect to longitudinal direction L of the needle board, in such a way that the angle of all needle rows 6 , 7 of one block 12 , 13 to longitudinal direction L of the needle board has a certain sign (+ or −), and the angle of all of first or second needle rows 6 , 7 of a first or second block 12 , 13 adjacent thereto in longitudinal direction L has the opposite sign. Often successive needle rows 6 , 7 have the same absolute value for this angle, as a result of which a homogeneous herringbone pattern can be formed in parts of the needle board.
[0025] In the needle board shown in FIG. 1 , a distinction is made between first needle rows 6 , which are combined into first blocks 12 , and second needle rows 7 , which are combined into second blocks 13 . It is clear from FIG. 1 that all of first or second needle rows 6 , 7 of a specific first or second block 12 , 13 are parallel to each other. In addition, the needles of first or second needle rows 6 , 7 of a first or second block 12 , 13 should ideally have the same spacing in the direction in which first or second needle rows 6 , 7 extend, and, considered in longitudinal direction L of the needle board, first or second needle rows 6 , 7 should begin and end at the same length, i.e., begin and end at points such that the rows are all of equal length. In the transverse direction Q of the needle board, first and second blocks 12 , 13 can extend over the entire width of the needle board or over only parts of it.
[0026] In the following, the first and second angles α, β are always to be understood as the smaller of the two angles of intersection of a first or second needle row 6 , 7 with a straight line extending in longitudinal direction L of the needle board. The absolute value of second angle β of second needle rows 7 to longitudinal direction L of the needle board is different from the absolute value of first angle α of first needle rows 6 to longitudinal direction L of the needle board. The absolute value of first angle α of first needle rows 6 to longitudinal direction L of the needle board is in the range of 10-30°, preferably of 15-25°, and even more preferably of 17-23°. The absolute value of second angle β of second needle rows 7 to longitudinal direction L of the needle board is in the range of 25-65°, preferably of 30-60°, and even more preferably of 42-48°.
[0027] First and second needle rows 6 , 7 are arranged in such a way that a projection 14 of first and second needle rows 6 , 7 in the transverse direction Q of the needle board, i.e., the direction perpendicular to the longitudinal direction of the needle board, yields at least certain sections in longitudinal direction L of the needle board where the longitudinal distances L 1 , L 2 between the projections 16 of the individual needles are different. Projections 16 of the needles within a block 12 , 13 of needle rows 6 , 7 comprise the same longitudinal distances L 1 , L 2 from each other.
[0028] In the present application, needle projections 16 within a first block 12 of first needle rows 6 are separated from each other by longitudinal distance L 1 , whereas needle projections 16 within a second block 13 of second needle rows 7 are separated from each other by longitudinal distance L 2 . Longitudinal distance L 1 separating needle projections 16 within a first block 12 of first needle rows 6 is in the range of 0.5-20 mm, preferably of 1.0-15 mm, and even more preferably of 2.0-5.0 mm. Longitudinal distance L 2 separating needle projections 16 within a second block 13 of second needle rows 7 is in the range of 0.3-15 mm, preferably of 0.7-10 mm, and even more preferably of 1.5-4.0 mm.
[0029] It is especially preferable for needle rows 6 , 7 to be arranged in such a way that a projection 18 of needle rows 6 , 7 in or opposite to longitudinal direction L of the needle board yields at least certain sections in the transverse direction Q of the needle board, preferably large areas or the entire area, where the transverse distances T between individual needle projections 20 are equal. This is best seen in the enlarged diagram of the detail “X” in FIG. 2 . The transverse distances T between individual needle projections 20 are in the range of 0.05-2.5 mm, preferably of 0.1-1.5 mm, and even more preferably of 0.2-1.0 mm.
[0030] It should be clear that the configuration of the needle board can be modified in many ways. This pertains to the number of needles 2 in each first and second needle row 6 , 7 , as well as to angles α and β of needle rows 6 , 7 to longitudinal direction L of the needle board, to the number of first and second needle rows 6 , 7 within a first or second block 12 , 13 , to the spacing of individual needles 2 from each other within a first or second needle row 6 , 7 , and also to the distances between individual blocks 12 , 13 or first and second needle rows 6 , 7 . It is also conceivable that the individual needles could be spaced apart in different ways within a needle row 6 , 7 .
[0031] The number of first and second blocks 12 , 13 is also variable as is their arrangement with respect to each other. Five blocks 12 , 13 are shown in FIG. 1 , i.e., three first blocks 12 of first needle rows 6 and two second blocks 13 of second needle rows 7 . First blocks 12 of first needle rows 6 are arranged one after the other, as are also second blocks 13 of second needle rows 7 . It would also be conceivable that first and second blocks 12 , 13 of first and second needle rows 6 , 7 could be arranged in alternating fashion or in any other desired sequence.
[0032] Finally, first and second needle rows 6 , 7 of first and second blocks 12 , 13 in FIG. 1 are arranged to form a herringbone pattern extending in longitudinal direction L of the needle board. It would also be conceivable that angled first and second needle rows 6 , 7 could be arranged differently, e.g., two or more successive first or second blocks 12 , 13 at a positive angle to longitudinal direction L and at least one other first or second block 12 , 13 at a negative angle to longitudinal direction L or vice versa.
[0033] The invention has been described so far on the basis of first and second blocks 12 , 13 of first and second needle rows 6 , 7 arranged to form a herringbone pattern. First and second needle rows 6 , 7 could also be arranged next to each other in such a way as to form a herringbone pattern without forming first and second blocks 12 , 13 .
[0034] A wide variety of materials are available for the various parts discussed and illustrated herein. While the principles of this device have been described in connection with specific embodiments, it should be understood clearly that these descriptions are made only by way of example and are not intended to limit the scope of the device. | The needle board for use in a needling machine for needling a flat textile material comprises first needle rows and second needle rows, wherein the first needle rows and the second needle rows are arranged inclined with respect to a longitudinal direction of the needle board, which longitudinal direction corresponds to a direction in which the flat textile material to be needled is conveyed in the needling machine. The first needle rows are arranged at a first angle to the longitudinal direction, and the second needle rows are arranged at a second angle to the longitudinal direction. An absolute value of the second angle is different from an absolute value of the first angle. | 3 |
This is a continuation of international application Ser. No. International Application Ser. No. PCT/DK99/00677, filed Dec. 3, 1999, the entire disclosure of which is hereby incorporated by reference.
TECHNICAL FIELD
The present invention relates generally to the biosynthesis of glycans found as free oligosaccharides or covalently bound to proteins and glycolipids. This invention is more particularly related to a family of nucleic acids encoding UDP-N-acetylglucosamine: N-acetylgalactosamine β1,6-N-acetylglucosaminyltransferases (Core-β1,6-N-acetylglucosaminyltransferases), which add N-acetylglucosamine to the hydroxy group at C6 of 2-acetamido-2-deoxy-D-galactosamine (GalNAc) in O-glycans of the core 3 and the core 1 type. This invention is more particularly related to a gene encoding the third member of the family of O-glycan , β1,6-N-acetylglucosaminyltransferases, termed C2/4GnT, probes to the DNA encoding C2/4GnT, DNA constructs comprising DNA encoding C2/4GnT, recombinant plasmids and recombinant methods for producing C2/4GnT, recombinant methods for stably transforming or transfecting cells for expression of C2/4GnT, and methods for identification of DNA polymorphism in patients.
BACKGROUND OF THE INVENTION
O-linked protein glycosylation involves an initiation stage in which a family of N-acetylgalactosaminyltransferases catalyzes the addition of N-acetylgalactosamine to serine or threonine residues (1). Further assembly of O-glycan chains involves several sucessive or alternative biosynthetic reactions: i) formation of simple mucin-type core 1 structures by UDP-Gal: GalNAcα-R β1,3Gal-transferase activity; ii) conversion of core 1 to complex-type core 2 structures by UDP-GlcNAc: Galβ1-3GalNAcα-R β1,6GlcNAc-transferase activities; iii) direct formation of complex mucin-type core 3 by UDP-GlcNAc: GlcNAcα β1,3GlcNAc-transferase activities; and iv) conversion of core 3 to core 4 by UDP-GlcNAc: GlcNAcβ1-3GalNAcα-R β1,6GlcNAc-transferase activity. The formation of 1,6GlcNAc branches (reactions ii and iv) may be considered a key controlling event of O-linked protein glycosylation leading to structures produced upon differentiation and malignant transformation (2-6). For example, increased formation of GlcNAcβ1-6GalNAc branching in O-glycans has been demonstrated during T-cell activation, during the development of leukemia, and for immunodeficiencies like Wiskott-Aldrich syndrome and AIDS (7; 8). Core 2 branching may play a role in tumor progression and metastasis (9). In contrast, many carcinomas show changes from complex O-glycans found in normal cell types to immaturely processed simple mucin-type O-glycans such as T (Thomsen-Friedenreich antigen; Gal 1-3GalNAc 1-R), Tn (GalNAc 1-R), and sialosyl-Tn (NeuAc 2-6GalNAc 1-R) (10). The molecular basis for this has been extensively studied in breast cancer, where it was shown that specific downregulation of core 2 β6GlcNAc-transferase was responsible for the observed lack of complex type O-glycans on the mucin MUCl (6). O-glycan core assembly may therefore be controlled by inverse changes in the expression level of Core-β1,6-N-acetylglucosaminyltransferases and the sialyltransferases forming sialyl-T and sialyl-Tn.
Interestingly, the metastatic potential of tumors has been correlated with increased expression of core 2 β6GlcNAc-transferase activity (5). The increase in core 2 β6GlcNAc-transferase activity was associated with increased levels of poly N-acetyllactosamine chains carrying sialyl-Le x , which may contribute to tumor metastasis by altering selectin mediated adhesion (4; 11). The control of O-glycan core assembly is regulated by the expression of key enzyme activities outlined in FIG. 1 ; however, epigenetic factors including posttranslational modification, topology, or competition for substrates may also play a role in this process (11).
The in vitro biosynthesis of a subset of complex O-glycopeptide structures is presently hampered by lack of availability of the enzymes adding N-acetylglucosamine in a β1-3 linkage to GalNAcα1-O-Ser/Thr to form core 3 as well as the enzyme catalyzing the successive addition of β1-6 N-acetylglucosamine branches to form core 4. This structure is required for the enzymes responsible for further build-up of core 4 based complex type O-glycans (FIG. 1 ). Most other enzymes required for elongation of branched O-glycans are available, and the core 2/4 enzyme described herein now makes the synthesis of core 4 based structures possible.
Access to the gene encoding C2/4GnT would allow production of a glycosyltransferase for use in formation of core 2 or core 4—based O-glycan modifications on oligosacccharides, glycoproteins and glycosphingolipids. This enzyme could be used, for example in pharmaceutical or other commercial applications that require synthetic addition of core 2 or core 4 based O-glycans to these or other substrates, in order to produce appropriately glycosylated glycoconjugates having particular enzymatic, immunogenic, or other biological and/or physical properties.
Consequently, there exists a need in the art for UDP-N-Acetylglucosamine: Galactose-β1,3-N-Acetylgalactosamine-α-R/N-Acetylglucosamine-β1,3-N-Acetyl-galactosamine-α-R (GlcNAc to GalNAc) β1-6 N-Acetylglucosaminyltransferase and the primary structure of the gene encoding these enzyme. The present invention meets this need, and further presents other related advantages.
SUMMARY OF THE INVENTION
The present invention provides isolated nucleic acids encoding human UDP-N-acetylglucosamine: N-acetylgalactosamine β1,6 N-acetylglucosaminyltransferasee (C2/4GnT), including cDNA and genomic DNA C2/4GnT has broader acceptor substrate specificities compared to C2GnT, as exemplified by its activity with core 3—R saccharide derivatives. The complete nucleotide sequence of C2/4GnT is set forth in SEQ ID NO:1 and FIG. 2 .
In one aspect, the invention encompasses isolated nucleic acids comprising the nucleotide sequence of nucleotides 496-1812 as set forth in SEQ ID NO:1 and FIG. 2 or sequence-conservative or function-conservative variants thereof Also provided are isolated nucleic acids hybridizable with nucleic acids having the sequence as set forth in SEQ ID NO:1 and FIG. 2 or fragments thereof or sequence-conservative or function-conservative variants thereof, preferably, the nucleic acids are hybridizable with C2/4GnT sequences under conditions of intermediate stringency, and, most preferably, under conditions of high stringency. In one embodiment, the DNA sequence encodes the amino acid sequence shown in SEQ ID NO:2 and FIG. 2 from methionine (amino acid no. 1) to leucine (amino acid no. 438). In another embodiment, the DNA sequence encodes an amino acid sequence comprising a sequence from phenylalanine (no. 31) to leucine (no. 438) of the amino acid sequence set forth in SEQ ID NO:2 and FIG. 2 .
In a related aspect, the invention provides nucleic acid vectors comprising C2/4GnT DNA sequences, including but not limited to those vectors in which the C2/4GnT DNA sequence is operably linked to a transcriptional regulatory element, with or without a polyadenylation sequence. Cells comprising these vectors are also provided, including without limitation transiently and stably expressing cells. Viruses, including bacteriophages, comprising C2/4GnT-derived DNA sequences are also provided. The invention also encompasses methods for producing C2/4GnT polypeptides. Cell-based methods include without limitation those comprising: introducing into a host cell an isolated DNA molecule encoding C2/4GnT, or a DNA construct comprising a DNA sequence encoding C2/4GnT; growing the host cell under conditions suitable for C2/4GnT expression; and isolating C2/4GnT produced by the host cell. A method for generating a host cell with de novo stable expression of C2/4GnT comprises: introducing into a host cell an isolated DNA molecule encoding C2/4GnT or an enzymatically active fragment thereof (such as, for example, a polypeptide comprising amino acids 31-438 of the amino acid sequence set forth in SEQ ID NO:2 and FIG. 2 ), or a DNA construct comprising a DNA sequence encoding C2/4GnT or an enzymatically active fragment thereof; selecting and growing host cells in an appropriate medium; and identifying stably transfected cells expressing C2/4GnT. The stably transfected cells may be used for the production of C2/4GnT enzyme for use as a catalyst and for recombinant production of peptides or proteins with appropriate galactosylation. For example, eukaryotic cells, whether normal or diseased cells, having their glycosylation pattern modified by stable transfection as above, or components of such cells, may be used to deliver specific glycoforms of glycopeptides and glycoproteins, such as, for example, as immunogens for vaccination.
In yet another aspect, the invention provides isolated C2/4GnT polypeptides, including without limitation polypeptides having the sequence set forth in SEQ ID NO:2 and FIG. 2 , polypeptides having the sequence of amino acids 31-438 as set forth in SEQ ID NO:2 and FIG. 2 , and a fusion polypeptide consisting of at least amino acids 31-438 as set forth in SEQ ID NO:2 and FIG. 2 fused in frame to a second sequence, which may be any sequence that is compatible with retention of C2/4GnT enzymatic activity in the fusion polypeptide. Suitable second sequences include without limitation those comprising an affinity ligand or a reactive group.
In another aspect of the present invention, methods are disclosed for screening for mutations in the coding region (exon III) of the C2/4GnT gene using genomic DNA isolated from, e.g., blood cells of patients. In one embodiment, the method comprises: isolation of DNA from a patient; PCR amplification of coding exon III; DNA sequencing of amplified exon DNA fragments and establishing therefrom potential structural defects of the C2/4GnT gene associated with disease.
These and other aspects of the present invention will become evident upon reference to the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts the biosynthetic pathways of mucin-type O-glycan core structures. The abbreviations used are GalNAc-T: polypeptide αGalNAc-transferase; ST6GalNAcI: mucin α2,6 sialyltransferase; C1β3Gal-T: core 1 β1,3 galactosyltransferase; C2GnT: core 2 β1,6 GlcNAc-transferase; C2/4GnT: core2/core 4 β1,6 GlcNAc-transferase; C3GnT: core 3 β1,3 GlcNAc-transferase; ST3Gall: mucin α2,3 sialyltransferase; β4Gal-T: β1,4 galactosyltransferase; β3Gal-T: β1,3 galactosyltransferase; β3GnT: elongation β1,3 GlcNAc-transferase.
FIG. 2 depicts the DNA sequence of the C2/4GnT (SEQ ID NO:1; accession # AF038650) gene and the predicted amino acid sequence of C2/4GnT. (SEQ ID NO:2). The amino acid sequence is shown in single letter code. The hydrophobic segment representing the putative transmembrane domain is double under-lined. Two consensus motifs for N-glycosylation are indicated by asterisks. The location of the primers used for preparation of the expression constructs are indicated by single underlining. A potential polyadenylation signal is indicated in boldface underlined type.
FIG. 3 is an illustration of a sequence comparison between human C2GnT (SEQ ID NO:11); (accession # M97347), human C2/4GnT (SEQ ID NO:2; accession # AF038650), and human I-GnT (SEQ ID NO: 12; accession # Z19550). Introduced gaps are shown as hyphens, and aligned identical residues are boxed (black for all sequences, and grey for two sequences). The putative transmembrane domains are underlined with a single line. The positions of conserved cysteines are indicated by asterisks. One conserved N-glycosylation sites is indicated by an open circle.
FIG. 4 depicts a Northern blot analysis of healthy human tissues and gastric cancer cell lines. Panel A: Multiple human tissue northern blots, MTN I and MTN II, from Clontech were probed with a 32 P-labeled probe corresponding to the soluble expression fragment of C2/4GnT (base pairs 91-1317). Panel B: A northern blot of total RNA from human colonic and pancreatic cancer cell lines was probed as described for panel A.
FIG. 5 depicts sections of a 1-D 1H-NMR spectrum of the C2/4GnT product GlcNAcβ1-3(GlcNAcβ1-6)GalNAcα1-1-pNph, showing all non-exchangeable monosaccharide ring methine and exocyclic methylene resonances. Residue designations for GlcNAcβ1→3 (β3), GlcNAcβ1→6 (β6), and GalNAcα1→1 (α) are followed by proton designations (1-6). All resonances in this region except for β3-5 (3.453 ppm) are marked.
FIG. 6 is a section of the 1 H-detected 1 H— 13 C heteronuclear multiple bond correlation (HMBC) spectrum of the Core 4 β6 GlcNAc transferase product, showing interglycosidic H1-C1-O1-Cx and C1-O1-Cx-Hx correlations (cross-peaks marked by ovals). The unmarked cross-peaks are all intra-residue correlations.
FIG. 7 shows a fluorescence in situ hybridization of C2/4GnT to metaphase chromosomes. The C2/4GnT probe (P1 DNA from clone DPMC-HFF#1-1091[F1]) labeled band 15q21.3
FIG. 8 is a schematic representation of forward (TSHC78) and reverse (TSHC79) PCR primers that can be used to amplify the coding exon of the C2/4GnT gene. The sequences of the primers are also shown. TSHC78 has SEQ ID NO:9 and TSHC79 has SEQ ID NO:10.
DETAILED DESCRIPTION OF THE INVENTION
All patent applications, patents, and literature references cited in this specification are hereby incorporated by reference in their entirety. In the case of conflict, the present description, including definitions, is intended to control.
Definitions:
1. “Nucleic acid” or “polynucleotide” as used herein refers to purine- and pyrimidine-containing polymers of any length, either polyribonucleotides or polydeoxyribonucleotides or mixed polyribo-polydeoxyribo nucleotides. This includes single- and double-stranded molecules, i.e., DNA-DNA, DNA-RNA and RNA-RNA hybrids, as well as “protein nucleic acids” (PNA) formed by conjugating bases to an amino acid backbone. This also includes nucleic acids containing modified bases (see below).
2. “Complementary DNA or cDNA” as used herein refers to a DNA molecule or sequence that has been enzymatically synthesized from the sequences present in a mRNA template, or a clone of such a DNA molecule. A “DNA Construct” is a DNA molecule or a clone of such a molecule, either single- or double-stranded, which has been modified to contain segments of DNA that are combined and juxtaposed in a manner that would not otherwise exist in nature. By way of non-limiting example, a cDNA or DNA which has no introns is inserted adjacent to, or within, exogenous DNA sequences.
3. A plasmid or, more generally, a vector, is a DNA construct containing genetic information that may provide for its replication when inserted into a host cell. A plasmid generally contains at least one gene sequence to be expressed in the host cell, as well as sequences that facilitate such gene expression, including promoters and transcription initiation sites. It may be a linear or closed circular molecule.
4. Nucleic acids are “hybridizable” to each other when at least one strand of one nucleic acid can anneal to another nucleic acid under defined stringency conditions. Stringency of hybridization is determined, e.g., by a) the temperature at which hybridization and/or washing is performed, and b) the ionic strength and polarity (e.g., formamide) of the hybridization and washing solutions, as well as other parameters. Hybridization requires that the two nucleic acids contain substantially complementary sequences; depending on the stringency of hybridization, however, mismatches may be tolerated. Typically, hybridization of two sequences at high stringency (such as, for example, in an aqueous solution of 0.5×SSC, at 65° C.) requires that the sequences exhibit some high degree of complementarity over their entire sequence. Conditions of intermediate stringency (such as, for example, an aqueous solution of 2×SSC at 65° C.) and low stringency (such as, for example, an aqueous solution of 2×SSC at 55° C.), require correspondingly less overall complementarily between the hybridizing sequences. (1×SSC is 0.15 M NaCl, 0.015 M Na citrate.)
5. An “isolated” nucleic acid or polypeptide as used herein refers to a component that is removed from its original environment (for example, its natural environment if it is naturally occurring). An isolated nucleic acid or polypeptide contains less than about 50%, preferably less than about 75%, and most preferably less than about 90%, of the cellular components with which it was originally associated.
6. A “probe” refers to a nucleic acid that forms a hybrid structure with a sequence in a target region due to complementarily of at least one sequence in the probe with a sequence in the target region.
7. A nucleic acid that is “derived from” a designated sequence refers to a nucleic acid sequence that corresponds to a region of the designated sequence. This encompasses sequences that are homologous or complementary to the sequence, as well as “sequence-conservative variants” and “function-conservative variants”. Sequence-conservative variants are those in which a change of one or more nucleotides in a given codon position results in no alteration in the amino acid encoded at that position. Function-conservative variants of C2/4GnT are those in which a given amino acid residue in the polypeptide has been changed without altering the overall conformation and enzymatic activity (including substrate specificity) of the native polypeptide; these changes include, but are not limited to, replacement of an amino acid with one having similar physico-chemical properties (such as, for example, acidic, basic, hydrophobic, and the like).
8. A “donor substrate” is a molecule recognized by, e.g., a Core-β1,6-N-acetyl-glucosaminyltransferase and that contributes an N-acetylglucosaminyl moiety for the transferase reaction. For C2/4GnT, a donor substrate is UDP-N-acetylglucosamine. An “acceptor substrate” is a molecule, preferably a saccharide or oligosaccharide, that is recognized by, e.g., an N-acetylglucosaminyltransferase and that is the target for the modification catalyzed by the transferase, i.e., receives the N-acetylglucosaminyl moiety. For C2/4GnT, acceptor substrates include without limitation oligosaccharides, glycoproteins, O-linked core 1- and core 3-glycopeptides, and glycosphingolipids comprising the sequences Gal 1-3GalNAc, GlcNAc 1-3GalNAc or Glc 1-3GalNAc.
The present invention provides the isolated DNA molecules, including genomic DNA and cDNA, encoding the UDP-N-acetylglucosamine: N-acetylgalactosamine 1,6 N-acetylglucosaminyltransferases (C2/4GnT).
C2/4GnT was identified by analysis of EST database sequence information, and cloned based on EST and 5′RACE cDNA clones. The cloning strategy may be briefly summarized as follows: 1) synthesis of oligonucleotides derived from EST sequence information, designated TSHC27 (SEQ ID NO:3) and TSHC28 (SEQ ID No.4); 2) successive 5′-rapid amplification of cDNA ends (5′RACE) using commercial Marathon-Ready cDNA; 3) cloning and sequencing of 5′RACE cDNA; 4) identification of a novel cDNA sequence corresponding to C2/4GnT; 5) construction of expression constructs by reverse-transcription-polymerase chain reaction (RT-PCR) using Colo205 human cell line mRNA; 6) expression of the cDNA encoding C2/4GnT in Sf9 ( Spodoptera frugiperda ) cells. More specifically, the isolation of a representative DNA molecule encoding a novel second member of the mammalian UDP-N-acetylglucosamine: β-N-acetylgalactosamine β1,6-N-acetylglucosaminyltransferase family involved the following procedures described below.
Identification of DNA Homologous C2nT.
Database searches were performed with the coding sequence of the human C2GnT sequence (12) using the BLASTn and tBLASTn algorithms against the dbEST database at The National Center for Biotechnology Information, USA. The BLASTn algorithm was used to identify ESTs representing the query gene (identities of 95%), whereas tBLASTn was used to identify non-identical, but similar EST sequences. ESTs with 50-90% nucleotide sequence identity were regarded as different from the query sequence. One EST with several apparent short sequence motifs and cysteine residues arranged with similar spacing was selected for further sequence analysis.
Cloning of Human C2/4GnT.
EST clone 178656 (5′ EST GenBank accession number AA307800), derived from a putative homologue to C2GnT, was obtained from the American Type Culture Collection, USA. Sequencing of this clone revealed a partial open reading frame with significant sequence similarity to C2GnT. The coding region of human C2GnT and a bovine homologue was previously found to be organized in one exon ((13), and unpublished observations). Since the 5′ and 3′ sequence available from the C2/4GnT EST was incomplete but likely to be located in a single exon, the missing 5′ and 3′ portions of the open reading frame was obtained by sequencing genomic P1 clones. P1 clones were obtained from a human foreskin genomic P1 library (DuPont Merck Pharmaceutical Co. Human Foreskin Fibroblast P1 Library) by screening with the primer pair TSHC27 (5′-GGAAGTTCATACAGTTCCCAC-3′) (SEQ ID NO:3) and TSHC28 (5′-CCTCCCATTCAACATCTTGAG -3′) (SEQ ID NO:4). Two genomic clones for C2/4GnT, DPMC-HFF#1-1026(E2) and DPMC-HFF#1-1091(F1) were obtained from Genome Systems Inc. DNA from P1 phage was prepared as recommended by Genome Systems Inc. The entire coding sequence of the C2/4GnT gene was represented in both clones and sequenced in full using automated sequencing (ABI377, Perkin-Elmer). Confirmatory sequencing was performed on a cDNA clone obtained by PCR (30 cycles at 95° C. for 15 sec; 55° C. for 20 sec and 68° C. for 2 min 30 sec) on total cDNA from the human COLO 205 cancer cell line with the sense primer TSHC54 (5′- GCAGAATTCATGGTTCAATGGAAGAGACTC-3′) (SEQ ID NO:7) and the anti-sense primer TSHC45 (5′-AGCGAATTCAGCTCAAAGTTCAGTCCCATAG -3′) (SEQ ID NO:5). The composite sequence contained an open reading frame of 1314 base pairs encoding a putative protein of 438 amino acids with type II domain structure predicted by the TMpred-algorithm at the Swiss Institute for Experimental Cancer Research (ISREC) (http://www isrec.isb-sib.chfsoftware/TMPRED_form.html). The sequence of the 5′-end of C2/4GnT mRNA including the translational start site and 5′-UTR was obtained by 5′ rapid amplification of cDNA ends (35 cycles at 94° C. for 20 sec; 52° C. for 15 sec and 72° C. for 2 min) using total cDNA from the human COLO 205 cancer cell line with the anti-sense primer TSHC48 (5′-GTGGGAACTGTATGAACTTCC-3′) (SEQ ID NO:6) (FIG. 2 ).
Expression of C2/4GnT.
An expression construct designed to encode amino acid residues 31-438 of C2/4GnT was prepared by PCR using P1 DNA, and the primer pair TSHC55 (5′-CGAGAATTCAGGTTGAAGTGTGACTC-3′) (SEQ ID NO:8) and TSHC45 (SEQ ID NO:5) (FIG. 2 ). The PCR product was cloned into the EcoRI site of pAcGP67A (PharMingen), and the insert was fully sequenced. pAcGP67-C2/4GnT-sol was co-transfected with Baculo-Gold™ DNA (PharMingen) as described previously (14). Recombinant Baculo-virus were obtained after two successive amplifications in Sf9 cells grown in serum-containing medium, and titers of virus were estimated by titration in 24-well plates with monitoring of enzyme activities. Transfection of Sf9-cells with pAcGP67-C2/4GnT-sol resulted in marked increase in GlcNAc-transferase activity compared to uninfected cells or cells infected with a control construct. C2/4GnT showed significant activity with disaccharide derivatives of O-linked core 1 (Galβ1-3GalNAcα1-R) and core 3 structures (GlcNAcβ1-3GalNAcα1-R). In contrast, no activity was found with lacto-N-neotetraose as well as GlcNAcβ1-3Gal-Me as acceptor substrates indicating that C2/4GnT has no IGnT-activity. Additionally, no activity could be detected wih α-D-GalNAc-1- para-nitrophenyl indicating that C2/4GnT does not form core 6 (GlcNAcβ1-6GalNAcα1-R) (Table I). No substrate inhibition of enzyme activity was found at high acceptor concentrations up to 20 mM core1—para-nitrophenyl or core3—para-nitrophenyl. C2/4GnT shows strict donor substrate specificity for UDP-GlcNAc, no activity could be detected with UDP-Gal or UDP-GalNAc (data not shown).
TABLE I
Substrate specificities of C2/4GnT and C2GnT
C2/4GnT a
C2Gnt
2
10
2
10
mM
mM
mM
mM
Substrate
nmol/h/mg
nmol/h/mg
β-D-Gal-(1-3)-α-D-GalNAc
2.8
7.3
9.6
19.0
β-D-Gal-(1-3)-α-D-GalNAc-1-p-Nph
16.1
21.8
16.2
23.6
β-D-GlcNAc-(1-3)-α-D-GalNAc-1-p-Nph
5.2
7.4
<0.1
<0.1
α-D-GalNAc-1-p-Nph
<0.1
<0.1
<0.1
<0.1
D-GalNAc
<0.1
<0.1
<0.1
<0.1
lacto-N-neo-tetraose
<0.1
<0.1
<0.1
<0.1
β-D-GlcNAc-(1-3)-β-D-Gal-1-Mc
<0.1
<0.1
<0.1
<0.1
a Enzyme sources were partially purified media of infectcd High Five ™ cells (see “Experimental Procedures”). Background values obtained with uninfected cells or cells infected with an irrelevant construct were subtracted.
b Me, methyl; Nph, nitrophenyl.
Controls included the pAcGP67-GalNAc-T3-sol (15). The kinetic properties were determined with partially purified enzymes expressed in High Five™ cells. Partial purification was performed by consecutive chromatography on Amberlite IRA-95, DEAE-Sephacryl and CM-Sepharose essentially as described (16).
Northern Blot Analysis of Human Organs.
Human multiple tissue northern blots containing mRNA from healthy human adult organs (Clontech) were probed with a C2/4GnT-probe. Northern analysis with mRNA from sixteen organs showed expression of C2/4GnT in organs of the gastrointestinal tract with high transcription levels observed in colon and kidney and lower levels in small intestine and pancreas (FIG. 4 A). To investigate changes in expression of C2/4GnT in cancer cells derived from tissues normally expressing C2/4GnT, mRNA levels in a panel of human adenocarcinoma cell lines were determined. Analyses of C2/4GnT transcription levels revealed differential expression in pancreatic cell lines: Capan-1 and AsPC-1 expressed the transcript, whereas PANC-1, Capan-2, and BxPC-3 did not (FIG. 4 B). Of the colonic cell lines, only HT-29 expressed transcripts of C2/4GnT. The size of the predominant transcript was approximately 2.4 kilobases, which correlates to the transcript size of 2.1 kilobases of the smallest of three transcripts of human C2GnT (12). Additionally, transcripts of approximately 3.4 kilobases and 6 kilobases were obtained in mRNA from healthy colonic mucosa (FIG. 4 A). The two additional transcripts may resemble the 3.3 kilobase and 5.4 kilobase transcripts of C2GnT, which have not yet been characterized. Multiple transcripts of C2GnT have been suggested to be caused by differential usage of polyadenylation signals, which affects the length of the 3′ UTR (12).
Genomic Organization of C2/4GnT Gene.
The present invention also provides isolated genomic DNA molecules encoding C2/4GnT. A human genomic foreskin P1 library (DuPont Merck Pharmaceutical Co. Human Foreskin Fibroblast P1 Library) by screening with the primer pair TSHC27 (5′-GGAAGTTCATACAGTTCCCAC-3′) (SEQ ID NO:3) and TSHC28 (5′-CCTCCCATTCAACATCTTGAG-3′) (SEQ ID NO:4), located in the coding exon yielding a product of 400 bp. Two genomic clones for C2/4GnT, DPMC-HFF#1-1026(E2) and DPMC-HFF#1-1091(F1) were obtained from Genome Systems Inc. The P1 clone was partially sequenced and introns in the 5′-untranslated region of C2/4GnT mRNA identified as shown in FIG. 6 . All exon/intron boundaries identified conform to the GT-AG consensus rule.
Chromosomal Localization of C2/4GnT Gene.
The present invention also discloses the chromosomal localization of the C2/4GnT gene. Fluorescence in situ hybridization to metaphase chromosomes using the isolated P1 phage clone DPMC-HFF#1-1091(F1) showed a fluorescence signal at 15q21.3 ( FIG. 7 ; 20 metaphases evaluated). No specific hybridization was observed at any other chromosomal site.
The C2/4GnT gene is selectively expressed in organs of the gastrointestinal tract. The C2/4GnT enzyme of the present invention was shown to exhibit O-glycosylation capacity implying that the C2/4GnT gene is vital for correct/full O-glycosylation in vivo as well. A structural defect in the C2/4GnT gene leading to a deficient enzyme or completely defective enzyme would therefore expose a cell or an organism to protein/peptide sequences which were not covered by O-glycosylationas seen in cells or organisms with intact C2/4GnT gene. Described in Example 6 below is a method for scanning the coding exon for potential structural defects. Similar methods could be used for the characterization of defects in the non-coding region of the C2/4GnT gene including the promoter region.
DNA, Vectors, and Host Cells
In practicing the present invention, many conventional techniques in molecular biology, microbiology, recombinant DNA, and immunology, are used. Such techniques are well known and are explained fully in, for example, Sambrook et al., 1989, Molecular Cloning: A Laboratory Manual , Second Edition, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.; DNA Cloning: A Practical Approach , Volumes I and II, 1985 (D. N. Glover ed.); Oligonucleotide Synthesis, 1984, (M. L. Gait ed.); Nucleic Acid Hybridization, 1985, (Hames and Higgins); Transcription and Translation, 1984 (Hames and Higgins eds.); Animal Cell Culture, 1986 (R. I. Freshney ed.); Immobilized Cells and Enzymes, 1986 (IRL Press); Perbal, 1984, A Practical Guide to Molecular Cloning , the series, Methods in Enzymology (Academic Press, Inc.); Gene Transfer Vectors for Mammalian Cells, 1987 (J. H. Miller and M. P. Calos eds., Cold Spring Harbor Laboratory); Methods in Enzymology Vol. 154 and Vol. 155 (Wu and Grossman, and Wu, eds., respectively); Immunochemical Methods in Cell and Molecular Biology, 1987 (Mayer and Waler, eds; Academic Press, London); Scopes, 1987, Protein Purification: Principles and Practice , Second Edition (Springer-Verlag, N.Y.) and Handbook of Experimental Immunology, 1986, Volumes I-IV (Weir and Blackwell eds.).
The invention encompasses isolated nucleic acid fragments comprising all or part of the nucleic acid sequence disclosed herein as set forth in SEQ ID NO:1 and FIG. 2 . The fragments are at least about 8 nucleotides in length, preferably at least about 12 nucleotides in length, and most preferably at least about 15-20 nucleotides in length. The invention further encompasses isolated nucleic acids comprising sequences that are hybridizable under stringency conditions of 2×SSC, 55 C, to the nucleotide sequence set forth in SEQ ID NO:1 and FIG. 2 ; preferably, the nucleic acids are hybridizable at 2×SSC, 65° C.; and most preferably, are hybridizable at 0.5×SSC, 65° C.
The nucleic acids may be isolated directly from cells. Alternatively, the polymerase chain reaction (PCR) method can be used to produce the nucleic acids of the invention, using either chemically synthesized strands or genomic material as templates. Primers used for PCR can be synthesized using the sequence information provided herein and can further be designed to introduce appropriate new restriction sites, if desirable, to facilitate incorporation into a given vector for recombinant expression.
The nucleic acids of the present invention may be flanked by natural human regulatory sequences, or may be associated with heterologous sequences, including promoters, enhancers, response elements, signal sequences, polyadenylation sequences, introns, 5′- and 3′-noncoding regions, and the like. The nucleic acids may also be modified by many means known in the art. Non-limiting examples of such modifications include methylation, “caps”, substitution of one or more of the naturally occurring nucleotides with an analog, internucleotide modifications such as, for example, those with uncharged linkages (e.g., methyl phosphonates, phosphotriesters, phosphoroamidates, carbamates, etc.) and with charged linkages (e.g., phosphorothioates, phosphorodithioates, etc.). Nucleic acids may contain one or more additional covalently linked moieties, such as, for example, proteins (e.g., nucleases, toxins, antibodies, signal peptides, poly-L-lysine, etc.), intercalators (e.g., acridine, psoralen, etc.), chelators (e.g., metals, radioactive metals, iron, oxidative metals, etc.), and alkylators. The nucleic acid may be derivatized by formation of a methyl or ethyl phosphotriester or an alkyl phosphoramidate linkage. Furthermore, the nucleic acid sequences of the present invention may also be modified with a label capable of providing a detectable signal, either directly or indirectly. Exemplary labels include radioisotopes, fluorescent molecules, biotin, and the like.
According to the present invention, useful probes comprise a probe sequence at least eight nucleotides in length that consists of all or part of the sequence from among the sequences as set forth in FIG. 2 or sequence-conservative or function-conservative variants thereof, or a complement thereof, and that has been labelled as described above.
The invention also provides nucleic acid vectors comprising the disclosed sequence or derivatives or fragments thereof A large number of vectors, including plasmid and fungal vectors, have been described for replication and/or expression in a variety of eukaryotic and prokaryotic hosts, and may be used for gene therapy as well as for simple cloning or protein expression.
Recombinant cloning vectors will often include one or more replication systems for cloning or expression, one or more markers for selection in the host, e.g. antibiotic resistance, and one or more expression cassettes. The inserted coding sequences may be synthesized by standard methods, isolated from natural sources, or prepared as hybrids, etc. Ligation of the coding sequences to transcriptional regulatory elements and/or to other amino acid coding sequences may be achieved by known methods. Suitable host cells may be transformed/transfected/infected as appropriate by any suitable method including electroporation, CaCl 2 mediated DNA uptake, fungal infection, microinjection, microprojectile, or other established methods.
Appropriate host cells included bacteria, archebacteria, fungi, especially yeast, and plant and animal cells, especially mammalian cells. Of particular interest are Saccharomyces cerevisiae, Schizosaccharomyces pombe, Pichia pastoris, Hansenula polymorpha, Neurospora , SF9 cells, C129 cells, 293 cells, and CHO cells, COS cells, HeLa cells, and immortalized mammalian myeloid and lymphoid cell lines. Preferred replication systems include M13, ColE1, 2 , ARS, SV40, baculovirus, lambda, adenovirus, and the like. A large number of transcription initiation and termination regulatory regions have been isolated and shown to be effective in the transcription and translation of heterologous proteins in the various hosts. Examples of these regions, methods of isolation manner of manipulation, etc. are known in the art. Under appropriate expression conditions, host cells can be used as a source of recombinantly produced C2/4GnT derived peptides and polypeptides.
Advantageously, vectors may also include a transcription regulatory element (i.e., a promoter) operably linked to the C2/4GnT coding portion. The promoter may optionally contain operator portions and/or ribosome binding sites. Non-limiting examples of bacterial promoters compatible with E. coli include: β-lactamase (penicillinase) promoter; lactose promoter; tryptophan (trp) promoter; arabinose BAD operon promoter; lambda-derived P 1 promoter and N gene ribosome binding site; and the hybrid tac promoter derived from sequences of the trp and lac UV5 promoters. Non-limiting examples of yeast promoters include 3-phosphoglycerate kinase promoter, glyceraldehyde-3 phosphate dehydrogenase (GAPDH) promoter, galactokinase (GAL1) promoter, galactoepimerase (GAL10) promoter, (CUP) copper cch and alcohol dehydrogenase (ADH) promoter. Suitable promoters for mammalian cells include without limitation viral promoters such as that from Simian Virus 40 (SV40), Rous sarcoma virus (RSV), adenovirus (ADV), and bovine papilloma virus (BPV). Mammalian cells may also require terminator sequences and poly A addition sequences and enhancer sequences which increase expression may also be included; sequences which cause amplification of the gene may also be desirable. Furthermore, sequences that facilitate secretion of the recombinant product from cells, including, but not limited to, bacteria, yeast, and animal cells, such as secretory signal sequences and/or prohormone pro region sequences, may also be included. These sequences are known in the art.
Nucleic acids encoding wild type or variant polypeptides may also be introduced into cells by recombination events. For example, such a sequence can be introduced into a cell, and thereby effect homologous recombination at the site of an endogenous gene or a sequence with substantial identity to the gene. Other recombination-based methods such as nonhomologous recombinations or deletion of endogenous genes by homologous recombination may also be used.
The nucleic acids of the present invention find use, for example, as probes for the detection of C2/4GnT in other species or related organisms and as templates for the recombinant production of peptides or polypeptides. These and other embodiments of the present invention are described in more detail below.
Polypeptides and Antibodies
The present invention encompasses isolated peptides and polypeptides encoded by the disclosed genomic sequence. Peptides are preferably at least five residues in length.
Nucleic acids comprising protein-coding sequences can be used to direct the recombinant expression of polypeptides in intact cells or in cell-free translation systems. The known genetic code, tailored if desired for more efficient expression in a given host organism, can be used to synthesize oligonucleotides encoding the desired amino acid sequences. The phosphoramidite solid support method of Matteucci et al., 1981, J. Am. Chem. Soc. 103:3185, the method of Yoo et al., 1989, J. Biol. Chem. 764:17078, or other well known methods can be used for such synthesis. The resulting oligonucleotides can be inserted into an appropriate vector and expressed in a compatible host organism.
The polypeptides of the present invention, including function-conservative variants of the sequence disclosed in SEQ ID NO:2, may be isolated from native or from heterologous organisms or cells (including, but not limited to, bacteria, fungi, insect, plant, and mammalian cells) into which a protein-coding sequence has been introduced and expressed. Furthermore, the polypeptides may be part of recombinant fusion proteins.
Methods for polypeptide purification are well known in the art, including, without limitation, preparative discontinues gel electrophoresis, isoelectric focusing, HPLC, reversed-phase HPLC, gel filtration, ion exchange and partition chromatography, and countercurrent distribution. For some purposes, it is preferable to produce the polypeptide in a recombinant system in which the protein contains an additional sequence tag that facilitates purification, such as, but not limited to, a polyhistidine sequence. The polypeptide can then be purified from a crude lysate of the host cell by chromatography on an appropriate solid-phase matrix. Alternatively, antibodies produced against a protein or against peptides derived therefrom can be used as purification reagents. Other purification methods are possible.
The present invention also encompasses derivatives and homologues of polypeptides. For some purposes, nucleic acid sequences encoding the peptides may be altered by substitutions, additions, or deletions that provide for functionally equivalent molecules, i.e., function-conservative variants. For example, one or more amino acid residues within the sequence can be substituted by another amino acid of similar properties, such as, for example, positively charged amino acids (arginine, lysine, and histidine); negatively charged amino acids (aspartate and glutamate); polar neutral amino acids; and non-polar amino acids.
The isolated polypeptides may be modified by, for example, phosphorylation, sulfation, acylation, or other protein modifications. They may also be modified with a label capable of providing a detectable signal, either directly or indirectly, including, but not limited to, radioisotopes and fluorescent compounds.
The present invention encompasses antibodies that specifically recognize immunogenic components derived from C2/4GnT. Such antibodies can be used as reagents for detection and purification of C2/4GnT.
C2/4GnT specific antibodies according to the present invention include polyclonal and monoclonal antibodies. The antibodies may be elicited in an animal host by immunization with C2/4GnT components or may be formed by in vitro immunization of immune cells. The immunogenic components used to elicit the antibodies may be isolated from human cells or produced in recombinant systems. The antibodies may also be produced in recombinant systems programmed with appropriate antibody-encoding DNA. Alternatively, the antibodies may be constructed by biochemical reconstitution of purified heavy and light chains. The antibodies include hybrid antibodies (i.e., containing two sets of heavy chain/light chain combinations, each of which recognizes a different antigen), chimeric antibodies (i.e., in which either the heavy chains, light chains, or both, are fusion proteins), and univalent antibodies (i.e., comprised of a heavy chain/light chain complex bound to the constant region of a second heavy chain). Also included are Fab fragments, including Fab′ and F(ab) 2 fragments of antibodies. Methods for the production of all of the above types of antibodies and derivatives are well known in the art. For example, techniques for producing and processing polyclonal antisera are disclosed in Mayer and Walker, 1987, Immunochemical Methods in Cell and Molecular Biology , (Academic Press, London).
The antibodies of this invention can be purified by standard methods, including but not limited to preparative disc-gel electrophoresis, isoelectric focusing, HPLC, reversed-phase HPLC, gel filtration, ion exchange and partition chromatography, and countercurrent distribution. Purification methods for antibodies are disclosed, e.g., in The Art of Antibody Purification, 1989, Amicon Division, W.R. Grace & Co. General protein purification methods are described in Protein Purification: Principles and Practice , R. K. Scopes, Ed., 1987, Springer-Verlag, New York, N.Y.
Anti C2/4GnT antibodies, whether unlabeled or labeled by standard methods, can be used as the basis for immunoassays. The particular label used will depend upon the type of immunoassay used. Examples of labels that can be used include, but are not limited to, radiolabels such as 32 P, 125 I, 3 H and 14 C; fluorescent labels such as fluorescein and its derivatives, rhodamine and its derivatives, dansyl and umbelliferone; chemiluminescers such as luciferia and 2,3-dihydrophthalazinediones; and enzymes such as horseradish peroxidase, alkaline phosphatase, lysozyme and glucose-6-phosphate dehydrogenase.
The antibodies can be tagged with such labels by known methods. For example, coupling agents such as aldehydes, carbodiimides, dimaleimide, imidates, succinimides, bisdiazotized benzadine and the like may be used to tag the antibodies with fluorescent, chemiluminescent or enzyme labels. The general methods involved are well known in the art and are described in, e.g., Chan (Ed.), 1987, Immunoassay: A Practical Guide , Academic Press, Inc., Orlando, Fla.
Core 2 O-glycans are involved in cell-cell adhesion events through selectin binding, and the core 2 beta6GlcNAc-transferase activity is required for synthesis of the selectin ligands (11). The core 2 beta6GlcNAc-transferase activity therefore plays a major role in selectin mediated cell trafficking including cancer metastasis. Since at least two different core 2 synthases exist it is required to define which of these are involved in synthesis of O-glycans in different cell types and in disease. Development of inhibitors of individual or all core 2 synthase activities may be usefull in reducing or eliminating core 2 O-glycans in cells and tissues, and hence inhibiting the biological events these ligands are involved in. Inhibition of transcription and/or translation of core 2 beta6GlcNAc-transferase genes may have the same effect. Compounds with such effects may be used as drugs with anti-inflammatory activity and/or for treatment of cancer growth and spreading.
The following examples are intended to further illustrate the invention without limiting its scope.
EXAMPLE 1
A: Identification of cDNA Homologous to C2/4GnT by Analysis of EST Database Sequence Information.
Database searches were performed with the coding sequence of the human C2GnT sequence ( ) using the BLASTn and tBLASTn algorithms against the dbEST database at The National Center for Biotechnology Information, USA. The BLASTn algorithm was used to identify ESTs representing the query gene (identities of 95%), whereas tBLASTn was used to identify non-identical, but similar EST sequences. ESTs with 50-90% nucleotide sequence identity were regarded as different from the query sequence. Composites of all the sequence information for each set of ESTs were compiled and analysed for sequence similarity to human C2GnT.
B: Cloning and Sequencing of C2/4GnT.
EST clone 178656 (5′ EST GenBank accession number AA307800), derived from a putative homologue to C2GnT, was obtained from the American Type Culture Collection, USA. Sequencing of this clone revealed a partial open reading frame with significant sequence similarity to C2GnT. The coding region of human C2GnT and a bovine homologue was previously found to be organized in one exon (13) and unpublished observations). Since the 5′ and 3′ sequence available from the C2/4GnT EST was incomplete but likely to be located in a single exon, the missing 5′ and 3′ portions of the open reading frame was obtained by sequencing genomic P1 clones. P1 clones were obtained from a human foreskin genomic P1 library (DuPont Merck Pharmaceutical Co. Human Foreskin Fibroblast P1 Library) by screening with the primer pair TSHC27 (5′-GGAAGTTCATACAGTTCCCAC-3′) (SEQ ID NO:3) and TSHC28 (5′-CCTCCCATTCAACATCTTGAG -3′) (SEQ ID NO:4). Two genomic clones for C2/4GnT, DPMC-HFF#1-1026(E2) and DPMC-HFF#1-1091(F1) were obtained from Genome Systems Inc. DNA from P1 phage was prepared as recommended by Genome Systems Inc. The entire coding sequence of the C2/4GnT gene was represented in both clones and sequenced in full using automated sequencing (ABI377, Perkin-Elmer). Confirmatory sequencing was performed on a cDNA clone obtained by PCR (30 cycles at 95° C. for 15 sec; 55° C. for 20 sec and 68° C. for 2 min 30 sec) on total cDNA from the human COLO 205 cancer cell line with the sense primer TSHC54 (5′-GCAGAATTCATGGTTCAATGGAAGAGACTC-3′) (SEQ ID NO:7) and the anti-sense primer TSHC45 (5′-AGCGAATTCAGCTCAAAGTTCAGTCCCATAG-3′) (SEQ ID NO:5). The composite sequence contained an open reading frame of 1314 base pairs encoding a putative protein of 438 amino acids with type II domain structure predicted by the TMpred-algorithm at the Swiss Institute for Experimental Cancer Research (ISREC) (http:flwww.isrec.isb-sib.ch/software/TMPRED_form.html). The sequence of the 5′-end of C2/4GnT mRNA including the translational start site and 5′-UTR was obtained by 5′ rapid amplification of cDNA ends (35 cycles at 94° C. for 20 sec; 52° C. for 15 sec and 72° C. for 2 min) using total cDNA from the human COLO 205 cancer cell line with the anti-sense primer TSHC48 (5′-GTGGGAACTGTATGAACTTCC-3′) (SEQ ID NO:6) (FIG. 2 ).
EXAMPLE 2
A: Expression of C2/4GnT in Sf9 Cells.
An expression construct designed to encode amino acid residues 31-438 of C2/4GnT was prepared by PCR using P1 DNA, and the primer pair TSHC55 (5′-CGAGAATTCAGGTTGAAGTGTGACTC -3′) (SEQ ID NO:8) and TSHC45 (SEQ ID NO:5) (FIG. 2 ). The PCR product was cloned into the EcoRI site of pAcGP67A (PharMingen), and the insert was fully sequenced. Plasmids pAcGP67-C2/4GnT-sol and pAcGP67-C2GnT-sol were co-transfected with Baculo-Gold™ DNA (PharMingen) as described previously (14). Recombinant Baculo-virus were obtained after two successive amplifications in Sf9 cells grown in serum-containing medium, and titers of virus were estimated by titration in 24-well plates with monitoring of enzyme activities. Controls included the pAcGP67-GalNAc-T3-sol (15).
B: Analysis of C2/4GnT Activity.
Standard assays were performed using culture supernatant from infected cells in 50 μl reaction mixtures containing 100 mM MES (pH 8.0), 10 mM EDTA, 10 mM 2-Acetamido-2-deoxy-D-glucono-1,5-lacton, 180 μM UDP-[ 14 C]-GlcNAc (6,000 cpm/nmol) (Amersham Pharmacia Biotech), and the indicated concentrations of acceptor substrates (Sigma and Toronto Research Laboratories Ltd., see Table I for structures). Semi-purified C2/4GnT was assayed in 50 μl reaction mixtures containing 100 mM MES (pH 7), 5 mM EDTA, 90 μM UDP-[ 14 C]-GlcNAc (3,050 cpm/nmol) (Amersham Pharmacia Biotech), and the indicated concentrations of acceptor substrates. Reaction products were quantified by chromatography on Dowex AG1-X8.
EXAMPLE 3
Restricted Organ Expression Pattern of C2/4GnT
Total RNA was isolated from human colon and pancreatic adenocarcinoma cell lines AsPC-1, BxPC-3, Capan-1, Capan-2, COLO 357, HT-29, and PANC-1 essentially as described (17). Twenty five μg of total RNA was subjected to electrophoresis on a 1% denaturing agarose gel and transferred to nitrocellulose as described previously (17). The cDNA-fragment of soluble C2/4GnT was used as a probe for hybridization. The probe was random primer-labeled using [α 32 P]dCTP and an oligonucleotide labeling kit (Amersham Pharmacia Biotech). The membrane was probed overnight at 42° C. as described previously (15), and washed twice for 30 min each at 42° C. with 2×SSC, 0.1% SDS and twice for 30 min each at 52° C. with 0.1×SSC, 0.1 % SDS. Human 20 multiple tissue Northern blots, MTN I and MTN II (CLONTECH), were probed as described above and washed twice for 10 min each at room temperature with 2×SSC, 0.1% SDS; twice for 10 min each at 55° C. with 1×SSC, 0.1 % SDS; and once for 10 min with 0.1×SSC, 0.1% SDS at 55° C.
EXAMPLE 4
Genomic Structure of the Coding Region of C2/4GnT
Human genomic clones were obtained from a human foreskin genomic P1 library (DuPont Merck Pharmaceutical Co. Human Foreskin Fibroblast P1 Library) by screening with the primer pair TSHC27 (5′-GGAAGTTCATACAGTTCCCAC-3′) (SEQ ID NO:3) and TSHC28 (5′-CCTCCCATTCAACATCTTGAG -3′) (SEQ ID NO:4). Two genomic clones for C2/4GnT, DPMC-HFF#1-1026(E2) and DPMC-HFF#1-1091(F1) were obtained from Genome Systems Inc. DNA from P1 phage was prepared as recommended by Genome Systems Inc. The entire coding sequence of the C2/4GnT gene was represented in both clones and sequenced in full using automated sequencing (ABI377, Perkin-Elmer). Intron/exon boundaries were determined by comparison with the cDNA sequences optimising for the gt/ag rule (Breatdnach and Chambon, 1981).
EXAMPLE 5
Chromosomal Localization of C2/4GnT: In Situ Hybridization to Metaphase Chromosomes
P1 DNA was labeled with biotin-14-dATP using the bio-NICK system (Life Technologies). The labeled DNA was precipitated with ethanol in the presence of herring sperm DNA. Precipitated DNA was dissolved and denatured at 80 C for 10 min followed by incubation for 30 min at 37 C and added to heat-denatured chromosome spreads where hybridization was carried out over night in a moist chamber at 37 C After posthybridization washing (50% formamide, 2×SSC at 42 C) and blocking with nonfat dry milk powder, the hybridized probe was detected with avidin-FITC (Vector Laboratories) followed by two amplification steps using rabbit-anti-FITC (Dako) and mouse-anti-rabbit FITC (Jackson Immunoresearch). Chromosome spreads were mounted in antifade solution with blue dye DAPI.
EXAMPLE 6
Analysis of DNA Polymorphism of C2/4GnT Gene
Primer pairs as described in FIG. 8 have been used for PCR amplification of individual sequences of the coding exon III. Each PCR product was subcloned and the sequence of 10 clones containing the appropriate insert was determined assuring that both alleles of each individual are characterized.
From the foregoing it will be evident that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention.
References
1. Clausen, H. and Bennett, E. P. A family of UDP-GalNAc: polypeptide N-acetylgalactosaminyl-transferases control the initiation of mucin-type O-linked glycosylation. Glycobiology, 6: 635-646, 1996.
2. Piller, F., Piller, V., Fox, R. I., and Fukuda, M. Human T-lymphocyte activation is associated with changes in O-glycan biosynthesis. J.Biol.Chem., 263: 15146-15150, 1988.
3. Yang, J. M., Byrd, J. C., Siddiki, B. B., Chung, Y. S., Okuno, M., Sowa, M., Kim, Y. S., Matta, K. L., and Brockhausen, I. Alterations of O-glycan biosynthesis in human colon cancer tissues. Glycobiology, 4: 873-884, 1994.
4. Yousefi, S., Higgins, E., Daoling, Z., Pollex-Kruger, A., Hindsgaul, O., and Dennis, J. W. Increased UDP-GlcNAc:Gal beta 1-3GalNAc-R (GlcNAc to GalNAc) beta-1,6- N-acetylglucosaminyltransferase activity in metastatic murine tumor cell lines. Control of polylactosamine synthesis. J.Biol.Chem., 266:1772-1782, 1991.
5. Fukuda, M. Possible roles of tumor-associated carbohydrate antigens. Cancer Res., 56: 2237-2244, 1996.
6. Brockhausen, I., Yang, J. M., Burchell, J., Whitehouse, C., and Taylor-Papadimitriou, J. Mechanisms underlying aberrant glycosylation of MUC1 mucin in breast cancer cells. Eur.J.Biochem., 233:607-617, 1995.
7. Brockhausen, I., Kuhns, W., Schachter, H., Matta, K. L., Sutherland, D. R., and Baker, M. A. Biosynthesis of O-glycans in leukocytes from normal donors and from patients with leukemia: increase in O-glycan core 2 UDP-GlcNAc:Gal beta 3 GalNAc alpha-R (GlcNAc to GalNAc) beta(1-6)-N-acetylglucosaminyltransferase in leukemic cells. Cancer Res., 51: 1257-1263, 1991.
8. Higgins, E. A., Siminovitch, K. A., Zhuang, D. L., Brockhausen, I., and Dennis, J. W. Aberrant O-linked oligosaccharide biosynthesis in lymphocytes and platelets from patients with the Wiskott-Aldrich syndrome. J.Biol.Chem., 266: 6280-6290, 1991.
9. Saitoh, O., Piller, F., Fox, R. I., and Fukuda, M. T-lymphocytic leukemia expresses complex, branched O-linked oligosaccharides on a major sialoglycoprotein, leukosialin. Blood, 77: 1491-1499, 1991.
10. Springer, G. F. T and Tn, general carcinoma autoantigens. Science, 224: 1198-1206, 1984.
11. Kumar, R., Camphausen, R. T., Sullivan, F. X., and Cumming, D. A. Core2 beta-1,6-N-acetylglucosaminyltransferase enzyme activity is critical for P-selectin glycoprotein ligand-1 binding to P-selectin. Blood, 88: 3872-3879, 1996.
12. Bierhuizen, M. F. and Fukuda, M. Expression cloning of a cDNA encoding UDP-GlcNAc:Gal beta 1-3-GalNAc-R (GlcNAc to GalNAc) beta 1-6GlcNAc transferase by gene transfer into CHO cells expressing polyoma large tumor antigen. Proc.Natl.Acad.Sci.U.S.A., 89: 9326-9330, 1992.
13. Bierhuizen, M. F., Maemura, K., Kudo, S., and Fukuda, M. Genomic organization of core 2 and I branching beta-1,6-N-acetylglucosaminyltransferases. Implication for evolution of the beta- 1,6-N-acetylglucosaminyltransferase gene family. Glycobiology, 5: 417425, 1995.
14. Almeida, R., Amado, M., David, L., Levery, S. B., Holmes, E. H., Merkx, G., van Kessel, A. G., Rygaard, E., Hassan, H., Bennett, E., and Clausen, H. A family of human beta4-galactosyltransferases. Cloning and expression of two novel UDP-galactose:beta-n-acetylglucosamine betal, 4-galactosyltransferases, beta4Gal-T2 and beta4Gal-T3. J.Biol.Chem., 272:31979-31991, 1997.
15. Bennett, E. P., Hassan, H., and Clausen, H. cDNA cloning and expression of a novel human UDP-N-acetyl-alpha-D-galactosamine. Polypeptide N-acetylgalactos-aminyltransferase, GalNAc-t3. J.Biol.Chem., 271: 17006-17012, 1996.
16. Wandall, H. H., Hassan, H., Mirgorodskaya, E., Kristensen, A. K., Roepstorff, P., Bennett, E. P., Nielsen, P. A., Hollingsworth, M. A., Burchell, J., Taylor-Papadimitriou, J., and Clausen, H. Substrate specificities of three members of the human UDP-N-acetyl- alpha-D-galactosamine:Polypeptide N-acetylgalactosaminyl-transferase family, GalNAc-T1, -T2, and -T3. J.Biol.Chem., 272: 23503-23514, 1997.
17. Sutherlin, M. E., Nishimori, I., Caffrey, T., Bennett, E. P., Hassan, H., Mandel, U., Mack, D., Iwamura, T., Clausen, H., and Hollingsworth, M. A. Expression of three UDP-N-acetyl-alpha-D-galactosamine:polypeptide GalNAc N-acetylgalactos-aminyltransferases in adenocarcinoma cell lines. Cancer Res., 57: 4744-4748, 1997. | A novel gene defining a novel human UDP-GlcNAc: Gal/Gl cNAcβ 1-3GalNAc αβ1, 6GlcNAc-transferase, termed C2/4GnT, with unique enzymatic properties is disclosed. The enzymatic activity of C2/4GnT is shown to be distinct from that of previously identified enzymes of this gene family. The invention discloses isolated DNA molecules and DNA constructs encoding C2/4GnT and derivatives thereof by way of amino acid deletion, substitution or insertion exhibiting C2/4GnT activity, as well as cloning and expression vectors including such DNA, cells transfected with the vectors, and recombinant methods for providing C2/4GnT. The enzyme C2/4GnT and C2/4GnT-active derivatives thereof are disclosed, in particular soluble derivatives comprising the catalytically active domain of C2/4GnT. Further, the invention discloses methods of obtaining 1,6-N-acetyl glucosaminyl glycosylated saccharides, glycopeptides or glycoproteins by use of an enzymically active C2/4GnT protein or fusion protein thereof or by using cells stably transfected with a vector including DNA encoding an enzymatically active C2/4GnT protein as an expression system for recombinant production of such glycopeptides or glycoproteins. Also a method for the identification for the identification of DNA sequence variations in the C2/4GnT gene by isolating DNA from a patient, amplifying C2/4GnT-coding exons by PCR, and detecting the presence of DNA sequence variation are disclosed. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to compositions comprising a blowing agent and a polyol, commonly referred to in the art as B-side compositions or blends, and use of such compositions to produce polyurethane and polyisocyanurate foams ("PUR/PIR foams"). More particularly, the invention relates to such blends, foaming processes and polyisocyanate-based foams which utilize blowing agent compositions comprised of 2-chloro-1,1,1,2-tetrafluoroethane ("HCFC-124" or "124").
Polyisocyanate-based foams are well known in the art in a variety of forms for a variety of purposes, including, for example, as roofing and siding insulation in building construction and as insulation in the manufacture of domestic and industrial refrigerators and freezers. The foams are typically produced by reaction of a polyisocyanate with a polyol, in the presence of a blowing agent. Historically, chlorofluorocarbons such as CFC-11 have been the blowing agents of choice. These materials, however, are being phased out for their possible involvement in affecting the stratospheric ozone and in global warming.
Various alternative blowing agents have been proposed, including gaseous blowing agents such as 142b, 134a and 134, use of the latter, for example, having been disclosed in WO 98/03580. The major drawback of these alternatives is the elevated pressure generated when they are blended with polyols because of their relatively low solubility. What is needed is a gaseous blowing agent which has superior solubility characteristics in polyols and is therefore easier to use than other low boiling blowing agents.
HCFC-124 is disclosed in U.S. Pat. No. 4,972,003 and WO 91/14732 as a blowing agent, but not exemplified. JP 57040533 discloses HCFC-124 as a blowing agent, but only exemplifies its use for co-blowing with CFC-11.
BRIEF SUMMARY OF THE INVENTION
Homogenous B-side compositions for the preparation of polyisocyanate-based polymer foams are provided, which compositions comprise (a) a liquid polyol (such as a polyether or a polyester polyol) and (b) a gaseous blowing agent comprising 124 dissolved in said polyol, as well as processes for producing closed-cell polyurethane or polyisocyanurate polymer foams comprising contacting an isocyanate-containing component with a polyol component in the presence of a blowing agent comprising 124, said blowing agent being dissolved in said polyol component to form a homogenous solution.
One or more conventional co-blowing agents, other than chlorofluorocarbons such as CFC-11, can also be blended with the 124, such as water (for generation of carbon dioxide); other HCFCs such as 1-chloro-1,1-difluoroethane (142b); hydrofluorocarbons such as 1,1,1,2-tetrafluoroethane (134a), 1,1,2,2-tetrafluoroethane (134), 1,1-difluoroethane (152a), 1,1,1-trifluoroethane (143a), difluoromethane (32) and pentafluoroethane (125); and hydrocarbons such as cyclopentane, n-pentane or i-pentane.
DETAILED DESCRIPTION
It has now been found that HCFC-124 is unexpectedly more soluble in conventional liquid polyols than other gaseous hydrochlorofluorocarbons or hydrofluorocarbons, so that at any given pressure (such as at 1 bar) one can incorporate more blowing agent into the polyol component. And, as noted in the aforementioned WO 98/03580, this in turn enables one to obtain a more homogenous polyol/isocyanate reaction mixture, lower density foams, and foams having a more uniform cell structure.
The key parameters for the production of isocyanate-based foams are conventional and are shown, among other places, in the aforementioned WO 98/03580 and in U.S. Pat. No. 5,300,534. The detailed descriptions of these patents are incorporated by reference for their disclosures of the type and ratio of components such as polyisocyanate, polyol, catalyst, surfactant, chain extender and the like.
While any suitable polyol or mixtures thereof can thus be used, examples comprise polyether polyols such as polyethylene oxides, polypropylene oxides, aromatic or aliphatic amine-based polyols, and sorbitol based polyether polyols (such as A3544 available commercially from Arco Chemical) as well as polyester polyols such as those made by transesterifying polyethylene terephthalate scrap with a glycol such as diethylene glycol; an example of a commercially available polyester polyol is Hoechst's Terate 2541.
The 124 blowing agent is preferably incorporated into the B-side with the liquid polyol. Whether used separately or as part of the B-side, the concentration of blowing agent relative to that of the combined weight of the blowing agent and the polyol is typically in the range of about 2-60 weight % (preferably about 5 to 45 weight %),
While any suitable polyisocyanate can be used in the foam-making process, examples of suitable polyisocyanates useful for making polyisocyanate-based foam comprise at least one of aromatic, aliphatic and cycloaliphatic polyisocyanates, among others. Representative members of these compounds comprise diisocyanates such as meta- or paraphenylene diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, hexamethylene-1,6-diisocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, hexahydrotoluene diisocyanate (and isomers), naphthylene-1,5-diisocyanate, 1-methylphenyl-2,4-phenyldiisocyanate, diphenylmethane-4,4-diisocyanate, diphenylmethane-2,4-diisocyanate, 4,4-biphenylenediisocyanate and 3,3-dimethyldiphenylpropane-4,4-diisocyanate; triisocyanates such as toluene-2,4,6-triisocyanate and polyisocyanates such as 4,4-dimethyldiphenylmethane-2,2,5,5-tetraisocyanate and the diverse polymethylenepolyphenylpolyisocyanates, mixtures thereof, among others. The isocyanate index (ratio of equivalents of isocyanates to equivalents of the polyol's active hydrogen-containing groups) is advantageously from about 0.9 to about 10, in most cases from about 1.0 to about 4.0.
It is often desirable to employ minor amounts of certain other ingredients in preparing polyisocyanate-based foams. Among these other ingredients comprise one or more members from the group consisting of catalysts, surfactants, flame retardants, preservatives, colorants, antioxidants, reinforcing agents, filler, antistatic agents, among others well known in this art.
Depending upon the composition, a surfactant can be employed to stabilize the foaming reaction mixture while curing. Such surfactants may comprise a liquid or solid organosilicone compound. The surfactants are employed in amounts sufficient to stabilize the foaming reaction mixture against collapse and to prevent the formation of large, uneven cells. About 0.2 to about 5 parts or more of the surfactant per 100 parts by weight polyol are usually sufficient.
One or more catalysts for the reaction of the polyol with the polyisocyanate may also be employed. While any suitable urethane catalyst may be employed, specific catalysts comprise tertiary amine compounds and organometallic compounds. Exemplary such catalysts are disclosed, for example, in U.S. Pat. No. 5,164,419, which disclosure is incorporated herein by reference. For example, a catalyst for the trimerization of polyisocyanates, such as an alkali metal alkoxide, alkali metal carboxylate, or quaternary amine compound, may also optionally be employed. Such catalysts are used in an amount which measurably increases the rate of reaction of the polyisocyanate. Typical amounts are about 0.1 to about 5 parts of catalyst per 100 parts by weight of polyol.
In the process of making the foam, the B-side blend, polyisocyanate and other components are contacted, thoroughly mixed, and permitted to expand and cure into a cellular polymer foam. The mixing apparatus is not critical.
The invention composition and processes are applicable to the production of all kinds of expanded polyurethane foams, including, for example, integral skin, RIM and flexible foams, and in particular rigid closed-cell polymer foams useful in spray insulation as foam-in-place appliance foams, or rigid insulating board stock and in laminates.
EXAMPLES
The following examples are given to illustrate the invention and should not be interpreted as limiting in any way. Unless stated otherwise, all parts and percentages are given by weight.
Examples 1 and 2 illustrate solubility of 124 in comparison to several of the known blowing agents (142b, 134 and 134a) and have been conducted according to the following procedure: (a) a known mass of liquid polyol is introduced inside an aerosol can; (b) after sealing the can, a known mass of blowing agent is added; (c) the aerosol can is vigorously stirred for 30 minutes; (d) the partial pressure of the blowing agent is measured once the can has been conditioned at 25° C.; (e) the aerosol can is then partially decompressed and the weight loss is recorded; (f) after a new manual stirring, followed by a conditioning at 25° C., the pressure inside the can is noted; (g) knowing the free volume inside the can, the initial air partial pressure, the weight loss after the decompression, this last pressure determination enables one to calculate the residual equilibrium partial pressure of the gaseous blowing agent. By applying this procedure, the amount of blowing agent solubilized is then determined as a function of its partial pressure.
Table I gives the saturated vapor pressure at 25° C. of the blowing agents studied hereafter:
TABLE I______________________________________Blowing Boiling Psat (bar) Agent Point (° C.) @ 25° C.______________________________________124 -12.1 3.8 142b -9.6 3.4 134a -26.4 6.6 134 -20.7 5.2______________________________________
Example 1
Solubility in A3544 Polyether Polyol
Table II represents the results of solubility tests in the subject sorbitol-based polyol. In this table, there are 2 lines of data for each of the 4 blowing agents tested, the top line indicating mole of blowing agent dissolved per 100 g of polyol and the bottom line indicating the partial pressure of that amount of blowing agent. Because several more readings were taken for 124 than for the other blowing agents, only representative readings are shown in the tables (the omitted readings do not materially differ from the data given):
TABLE II______________________________________Blowing Agent Mole Dissolved and Partial Pressure______________________________________124 .016 .038 .064 .084 .114 .147 .226 0.13 0.19 0.46 0.60 0.99 1.35 1.79 142b .019 .037 .059 .074 0.38 0.55 0.81 1.03 134 .038 .057 .073 .088 0.43 0.61 0.85 1.05 134a .023 .044 .053 .070 .0.85 1.22 1.43 1.91______________________________________
These determinations show clearly the unexpected good solubility of 124 in the polyether polyol studied. Thus, at any given pressure, it is possible to incorporate more 124 into the polyol than any of the other blowing agents.
Example 2
Solubility in T2541 Polyester Polyol
Table III represents the results of solubility tests in the subject polyester polyol:
TABLE III______________________________________Blowing Agent Mole Dissolved and Partial Pressure______________________________________124 .011 .019 .032 .040 .048 .052 .064 .079 0.42 0.54 0.55 0.69 0.95 1.07 1.28 1.38 142b .022 .031 .040 .064 0.74 0.80 0.90 1.84 134 .021 .039 .054 .063 0.41 0.80 1.28 1.17 134a .008 .014 .020 .027 0.85 1.05 1.26 1.62______________________________________
These results again show the unexpected good solubility of 124. In particular, for a blowing agent partial pressure of 1 bar, 124 is the blowing agent, among those tested, which permits incorporation of the greatest number of mole in the polyol.
Example 3
Foaming Tests
The following mixture was prepared:
100 parts of a polyol system (Arco Chemical's A2055 which includes polyether polyol, water, catalyst and surfactant), to which was added, in a pressurized container, 20 parts of 124.
This mixture was then reacted at 18° C. with 129.5 parts of Suprasec DNR, a polymeric methylene diisocyanate available from ICI, resulting in a rigid polyurethane foam with the characteristics shown in Table IV:
TABLE IV______________________________________Cream Time: 15 seconds Gel Time: 190 seconds Tack-free time: >300 seconds Core density: 28 g/l Compression set (kPa) Parallel maxi 103 @ 6% Perpendicular maxi 102 @ 10%______________________________________ | B-side compositions comprising a polyol and a gaseous blowing agent comprising 124 dissolved in the polyol are provided, as are processes for producing closed-cell polyurethane or polyisocyanurate polymer foam comprising contacting an isocyanate-containing component with a polyol component in the presence of a blowing agent comprising 124, said blowing agent being dissolved in said polyol component. | 2 |
“This application is a continuation of application Ser. No. 09/121,938 filed on Jul. 24, 1998, now U.S. Pat. No. 5,981,828, which is a divisional of application Ser. No. 08/647,424, filed Mar. 11, 1996, now U.S. Pat. No. 5,824,078, issued Oct. 20, 1998.”
BACKGROUND OF THE INVENTION
The present invention relates to composite allografts used in orthopedic surgery, and in particular to a composite acetabular allograft cup, to a method and apparatus for forming the composite acetabular allograft cup, and to a method of using the composite acetabular allograft cup in hip replacement surgery.
There is a need for methods of replacing or strengthening certain types of bone defects; for example, in the case of hip replacement surgery. A hip joint is a ball and socket joint in which the ball is the femoral head and the socket is called the acetabulum (due to its supposed resemblance to a vinegar cruet). The cavity of the acetabulum is formed from three parts of the pelvic bone: above by the ilium, behind and below by the ischium, and internally by the os pubis. Patients who are otherwise candidates for hip replacement surgery may have acetabular defects. The acetabulum may for various reasons, including disease, trauma or prior surgery, contain defects such as missing or eroded portions of the acetabular wall. These defects must be corrected or compensated if the surgery is to be successful.
In hip replacement surgery, a hip joint prosthesis, comprising a femoral component and an acetabular component, is employed to replace the femoral head and the acetabulum. The acetabular component may include a hemispherical metal cup or ring and a low-friction plastic liner of ultra-high molecular weight polyethylene. The procedure may also be done without the metal cup, using only the liner which is cemented in place.
One method of dealing with an acetabular defect is to repair the defect with a bone graft (either an allograft, typically harvested from a cadaver, or an autograft from the patient's own bone tissue). Due to the significant weight bearing role of the hip joint, the stability and strength of the bone graft is a major concern. Metallic support cups may be required to support the bone graft material as disclosed in MacCollum (U.S. Pat. No. 4,904,265). MacCollum discloses a support cup in the shape of a rigid metallic hemisphere with a flange to support the bone graft. The outer surface of the support cup is disclosed to be porous to support bone ingrowth. A bearing insert of low friction material for receiving the ball of the femoral prosthesis is mounted within the support cup.
As an alternative to bone grafts, Grimes (U.S. Pat. No. 5,176,711) discloses an acetabular hip prosthesis in which the acetabular component of the prosthesis includes an augmentation piece to fill a rim or cavitary defect. Likewise, Collazo (U.S. Pat. No. 5,326,368) discloses a modular prosthetic acetabular cup to provide various cross sections as desired to fill acetabular defects.
Another method of remedying an acetabular defect is disclosed in “Bone Grafting in Total Hip Replacement for Acetabular Protrusion” by McCollum, et al., Journal of Bone and Joint Surgery , Vol. 62-A, No. 7, 1065-1073 (October 1980). The McCollum article discloses the use of wafers of bone to fill a defect in the acetabular wall.
A slightly different technique is disclosed in “Bone Grafting in Total Hip Replacement for Acetabular Protrusion” by Slooff, et al., Acta Orthop. Scand , 55, 593-596, (1984). While Slooff et al. disclose the use of a bone graft to close an acetabular defect, Slooff et al. also disclose surrounding the graft with a wall of cancellous bone chips which are molded and impacted by using the socket trial prosthesis. (Cancellous bone has a spongy or lattice-like structure and may be derived from cadaverous bone tissue such as femoral heads.) Slooff et al. disclose a technique of repairing an acetabular defect in which cancellous bone chips are molded and impacted around a bone graft, but do not disclose the addition of cement to the impacted bone chips.
Gie, et al. in “Impacted Cancellous Allografts and Cement for Revision Total Hip Arthroplasty”, The Journal of Bone and Joint Surgery , Vol. 75-B, No. 1, 14-21 (January 1973) disclose the use of impacted cancellous allografts and cement for fixation of the femoral component in total hip arthroplasty. The technique disclosed by Gie et al. involves packing allograft bone chips into the femoral canal using the trial femoral component. The chips are repeatedly impacted after which cement is introduced and pressurized to force the cement into the graft. Pressure is maintained until the cement has sufficiently solidified. While Gie et al. disclose impacting cancellous bone chips into the femoral canal after which cement is added to the impacted bone chips and pressurized to force the cement into the graft, Gie et al. do not disclose the use of this technique in relation to the acetabulum. Neither Slooff et al. nor Gie et al. disclose the formation of a composite acetabular cup outside the body of the patient prior to surgery.
It is known to form human tissue into particular shapes to create desired natural tissue grafts. For example, U.S. Pat. No. 4,678,470 issued to Nashef et al. on Jul. 7, 1987 for “Bone-Grafting Material” discloses a bone grafting material derived from allogenic or xenogenic bone which may be machined into a predetermined shape.
U.S. Pat. No. 5,329,846 issued to Bonutti on Jul. 19, 1994 for “Tissue Press and System” discloses a press for shaping or compressing a piece of tissue by the movement of two members relative to each other. Various shapes of the two movable members may be selected so as to produce tissue in the desired shape. While the Bonutti invention is primarily directed to the compression and shaping of soft tissue, portions of the disclosure suggest the shaping of bone tissue with the addition of polymeric material (column 11, lines 11-13). Bonutti does not expressly disclose the formation of an acetabular cup using cancellous bone chips and cement. Furthermore, the Bonutti press does not disclose a press of the rack-and-pinion type. While Bonutti discloses the importance of monitoring and controlling the pressure applied to the compressed tissue, it is in the context of maintaining graft tissue in a living state to improve graft viability and tissue healing. In this context Bonutti discloses the use of pressure sensors and force-limiting means such as the mechanism found on torque wrenches. FIG. 6A of Bonutti discloses such a torque limiting mechanism and a pressure gauge.
Rack-and-pinion gearing and load switches are known in the art of manual presses used by machinists and in manufacturing environments. For example, the common arbor press may operate by means of a manual lever through rack-and-pinion gearing. See, for an example in an unrelated art, U.S. Pat. No. 3,686,922. Likewise, U.S. Pat. No. 3,741,706 issued to Conley, et al. on Jun. 26, 1973 discloses a molding device for forming a shaped object (a toy) from a soft moldable material. A manually operated lever acting through a pair of rack-and-pinion gear mechanisms is used to move one part of a mold against the other half of a mold to mold a three dimensional object. It is known to use pressure gauges, load limiting devices and the like in presses in the manufacturing environment. An example is U.S. Pat. No. 3,786,676 which discloses a compression testing machine having an in-line load cell.
SUMMARY OF THE INVENTION
The present invention includes a device (the acetabular allograft press), a method for using the press in forming a composite acetabular allograft cup from impacted cancellous bone chips and cement, the composite acetabular allograft cup itself, and the method of using the acetabular allograft cup in hip replacement surgery.
The acetabular allograft press comprises a loading frame which applies pressure to a two piece mold in the shape of the required acetabular cup. Various sizes of molds may be employed for different patient requirements. Pressure is applied by a manually operated lever through a rack-and-pinion gear mechanism to a plunger attached to one part of the mold; i.e., the plunger head. A plurality of compression load switches are located in-line with the plunger so as to indicate the correct degree of loading to the mold.
The method of using the acetabular allograft press comprises the following steps:
(a) A quantity of cancellous bone chips is placed in the mold (cancellous bone chips are commercially available);
(b) Pressure is applied to the bone chips to cause the chips to conform to the shape of the mold (it is important that the load applied to the bone chips is limited to avoid crushing the bone to more than a minor degree);
(c) The mold is opened and additional bone chips are added to fill any voids;
(d) A load is again placed on the bone chips to cause the newly added bone chips to conform to the shape of the mold;
(e) Commercially available bone cement is added to the mold;
(f) The mold is again loaded and the load is maintained for a sufficient period of time for the cement to harden.
This process produces a synthetic composite acetabular cup in which the inner surface is smooth and comprised essentially of hardened bone cement material. The outer portion of the cup may have a limited proportion of cement extrusions but the major portion of the exterior of the cup shows exposed cancellous bone surface. The acetabular cup is therefore suited to provide a smooth, strong inner surface to receive an acetabular implant, while the outer surface is suited for encouraging bone growth from the acetabulum into the exposed bone of the acetabular cup. While this technique is disclosed with reference to the particular application of an acetabular cup, the same techniques offer advantages in other applications where an allograft having the described properties is desirable. The present invention should not, therefore, be seen as limited to one particular application.
In surgery, the acetabular cup is highly advantageous since it avoids the necessity of performing grafting to correct acetabular defects such as by the method disclosed in Gie et al. The acetabular cup made by the method of the present invention could be formed in advance of surgery. During surgery the acetabular cup is positioned in the acetabulum so as to fill the acetabular defect and fixed in place by screws. The remainder of the total hip replacement surgery would be carried out using well known techniques. Using the surgical method of the present invention, however, a metal acetabular cup component is not required. A high density plastic liner is affixed with bone cement directly to the synthetic composite acetabular cup to receive the femoral component. The use of the apparatus and methods of the present invention are not limited to the acetabulum, but may be used to form synthetic allografts for other purposes in orthopedic surgery which would be apparent to one skilled in the art.
It is therefore an object of the present invention to provide for a synthetic composite allograft, a method of forming a composite allograft, and method of employing a composite allograft in surgical procedures.
It is also an object of the present invention to provide for a synthetic composite acetabular cup for the repair of acetabular defects encountered in total hip replacement surgery.
It is a further object of the present invention to provide for a synthetic composite allografts, and in particular for a synthetic composite acetabular cup, which presents a smooth, strong inner surface of hardened cement material and an outer surface consisting essentially of compacted cancellous bone chips.
It is also an object of the present invention to provide for a press and mold capable of producing a synthetic composite allograft, and in particular a composite acetabular cup, which presents a strong inner surface of hardened cement material and an outer surface consisting essentially of compacted cancellous bone chips.
It is a still further object of the present invention to provide for a method of using a press and mold to produce a synthetic composite allograft, and in particular a composite acetabular cup, which presents a strong inner surface of hardened cement material and an outer surface consisting essentially of compacted cancellous bone chips.
It is an additional object of the present invention to provide for a method of using a synthetic composite allograft in surgical procedures, and in particular a composite acetabular cup in total hip replacement surgery.
Further objects and advantages of the present invention will become apparent from an examination of the detailed description of the preferred embodiments considered in conjunction with the appended drawings as described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of the press and mold for producing a synthetic composite acetabular cup showing the plunger head depressed into the mold.
FIG. 2 is a front elevational view of the press and mold for producing a synthetic composite acetabular cup showing the plunger head retracted from the mold.
FIG. 3 is a side elevational view of the press and mold for producing a synthetic composite acetabular cup.
FIG. 4 is a partial sectional side elevational view of the press and mold for producing a synthetic composite acetabular cup showing the plunger head retracted from the mold.
FIG. 5 is a partial exploded view of the mold, plunger head, and synthetic composite acetabular cup.
FIG. 6 is a partial sectional view of the plunger head and mold as positioned for the formation of the synthetic composite acetabular cup.
FIG. 7 is a plan view of the inner surface of the synthetic composite acetabular cup showing holes in the dome of the cup for receiving bone fixation screws.
FIG. 8 is a plan view of the outer surface of the synthetic composite acetabular cup showing minimal cement extrusions amid the compacted cancellous bone chips.
FIG. 9 is a sectional elevational view of the synthetic composite acetabular cup.
FIG. 10 is a lateral sectional view through the acetabulum showing typical defects of the acetabular wall.
FIG. 11 is a lateral sectional view through the acetabulum showing the acetabulum prepared to receive the synthetic composite acetabular cup.
FIG. 12 is an exploded view of the components employed to implant the synthetic composite acetabular cup in relation to the sectioned acetabulum.
FIG. 13 is a lateral sectional view through the acetabulum with the synthetic composite acetabular cup and high density polyethylene insert implanted in the acetabulum.
FIG. 14 is an anterior-posterior view of the acetabulum.
FIG. 15 is an anterior-posterior view of the acetabulum with the synthetic composite acetabular cup and high density polyethylene insert implanted in the acetabulum.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The press of the present invention may be described generally with reference to FIGS. 1 through 4. The main components of the press are mounted on a loading frame generally designated 10 . The loading frame 10 comprises a base plate 11 on which is mounted a plurality of vertical support columns 12 . The support columns 12 carry a plurality of transverse plates 13 . Each transverse plate 13 carries a linear bearing 14 which is vertically oriented. The linear bearings 14 are aligned to accept a plunger generally designated as 20 . The plunger 20 is constrained and guided by the linear bearings 14 to move up and down vertically with respect to the loading frame 10 .
The plunger 20 comprises an upper component 21 and a lower component 22 . At least two linear bearings 14 are disposed to guide the upper component 21 and at least two linear bearings 14 are disposed to guide the lower component 22 . This arrangement assures that the plunger 20 is guided properly in linear vertical manner. Disposed between the upper component 21 and lower component 22 of the plunger 20 is a compression yoke 30 . The compression yoke 30 comprises an upper arm 31 affixed to the upper component 21 of the plunger 20 and a lower arm 32 affixed to the lower component 22 of the plunger 20 .
The compression yoke 30 is a precisely calibrated component which deforms in response to a compression load applied between the upper arm 31 and lower arm 32 . Therefore, due to the connection between the compression yoke 30 and the upper component 21 and lower component 22 of the plunger 20 , any load applied to the plunger 20 results in a precisely known and measurable deformation of the compression yoke 30 . The deformation of the compression yoke 30 is reflected in a deflection of the upper arm 31 with respect to the lower arm 32 .
A plurality of load switches 40 is disposed between the upper arm 31 and lower arm 32 of the compression yoke 30 . Each load switch 40 is activated sequentially by increasing loads applied to, and therefore increasing deflections of, the compression yoke 30 . Since a load of approximately 1000 pounds will produce unacceptable crushing of the cancellous bone chips, the load switches may advantageously be set at increments below this level; e.g., at 250, 500, 750, and 1000 pounds of force. Each load switch 40 is electrically connected to a display 41 by means of a cable 42 . The load switches 40 are set in a sequence so that a gradually increasing load applied to the plunger 20 activates each load switch 40 in sequence at a particular predetermined load. The activation of a particular load switch 40 results in the illumination of an indicator light 43 on the display 41 . (In the preferred embodiment of the present invention, the indicator lights 43 are light emitting diodes (LED's).) Thus, a particular desirable range of loads may be predetermined in advance so that the desirable range of loads is precisely and visually indicated by the illumination of a particular sequence of indicator lights 43 . The optimum load range for the practice of the present invention is from about 250 pounds to about 500 pounds. While the particular combination of the compression yoke 30 in conjunction with a plurality of load switches 40 and indicator lights 43 has been found to be effective in the practice of the present invention, the present invention is not limited to any particular means of measuring and indicating a particular compression load. Other forms of measuring and indicating a compression load applied to the plunger 20 would be readily apparent to one skilled in the art and the present invention is intended to encompass such alternative means for measuring and indicating a compression load.
In the preferred embodiment of the present invention, a compression load is applied to the plunger 20 by means of a manually operated rack-and-pinion gearing system. With reference to FIGS. 1 and 2, a manually operated handle 50 is connected to a shaft 51 which is constrained to move in a rotary fashion by rotary bearings 52 . Manual operation of the handle 50 results in rotary motion of the shaft 51 .
With reference to FIG. 4, a pinion gear 53 affixed to the shaft 51 is operatively engaged with a rack gear 54 disposed on the upper component 21 of the plunger 20 . Manual operation of the handle 50 results in rotary motion of the shaft 51 and through the rotation of the pinion gear 53 causes vertical motion of the plunger 20 by virtue of the action of the pinion gear 53 on the rack gear 54 .
With reference to FIGS. 1 through 4, a two-piece mold 60 comprising an outer mold 61 which is affixed to the base plate 11 and an inner mold 62 which is affixed to the lower component 22 of the plunger 20 is employed to form a composite allograft as will be described more fully hereinafter. It should be noted that the preferred embodiment of the present invention is described with respect to a mold for forming a composite acetabular allograft cup. The present invention is not limited to this particular application nor to the particular shape described for use as an acetabular cup. Any predetermined shape which can be formed by a two piece mold is suitable for the practice of the present invention.
In the particular case of a mold 60 for forming a composite acetabular allograft cup, a series of molds having the same general shape, namely that of a hemispherical dome, but of varying sizes to accommodate the varying sizes of the acetabulum found in different human patients, is desirable. For example, a series of molds with diameters from 60 to 70 millimeters at 2 millimeter increments would be adequate for most purposes. While the drawing figures illustrate a shape having a smooth inner surface, the scope of the present invention is not so limited. A shape having ridges or some other form of textured surface may have advantages in some applications.
The use of the composite allograft press described above may be described with reference to FIGS. 1 through 4 and in particular to FIGS. 5 and 6. First, a mold 60 is made to a predetermined shape as appropriate for the particular allograft application. In the particular case of a composite allograft used to repair defects in the acetabular wall, an acetabular cup 70 in the shape of a hollow hemispherical dome is desirable. Accordingly, the mold 60 illustrated in FIGS. 1 through 6 comprises an outer mold 61 having a hemispherical shape appropriate to the outer surface 71 of the acetabular cup 70 and an inner mold 62 , likewise having a similar hemispherical shape although of a smaller radius, so that the combination produces a hollow hemispherical dome sized to fit within the patient's acetabulum. The hollow hemispherical dome of the composite acetabular allograft cup 70 further has an inner surface 72 as shown in FIG. 9 sized to receive the other components required in total hip replacement as will be described more fully hereinafter.
In order to form a composite allograft, a quantity of cancellous bone chips 73 is placed in the outer mold 61 . Cancellous bone chips are derived from cadaverous bone and are characterized by a spongy or lattice-like structure. The cancellous bone chips 73 have the property of encouraging and accepting bone ingrowth from the defective acetabulum. Cancellous bone chips are commercially available. A size of one cubic centimeter is optimum for the practice of the invention, although a range of sizes above and below the optimum would be acceptable.
After placing the cancellous bone chips 73 in the outer mold 61 , a load is applied manually via the handle 50 to the plunger 20 and thereby to the inner mold 62 . The load applied to the cancellous bone chips 73 is for the purpose of conforming the cancellous bone chips 73 to the shape of the outer mold 61 . A minor amount of crushing of the cancellous bone chips 73 is acceptable and may even be desirable to assist in forming a compact and somewhat consolidated mass. However, excessive crushing of the bone chips could lead to the closing off of the lattice-like structure of the cancellous bone chips 73 so as to interfere with the desirable ingrowth of bone from the acetabulum once the acetabular cup 70 is implanted. Therefore, the operator may rely on the indicator lights 43 to avoid the application of excessive loads to the mold 60 . As noted above, the optimum range of loads is from about 250 to about 500 pounds. Loads of 1000 pounds or above should be avoided.
After conforming and consolidating the cancellous bone chips 73 , the mold 60 is opened and the consolidated cancellous bone chips 73 inspected for voids. If any voids occur, additional cancellous bone chips 73 may be added to the mold 60 . A load is then reapplied to the mold 60 to consolidate the newly added cancellous bone chips 73 . This process may be repeated as often as necessary to fill and consolidate any voids in the mass of cancellous bone chips 73 .
Once the cancellous bone chips 73 have been consolidated and conformed to the outer mold 61 so as to form the desired outer surface 71 without significant voids, a quantity of commercially available bone cement 74 is added to the mold 60 . The bone cement will typically be a methyl methacrylate type. A load is then reapplied to the mold 60 so as to cause the newly added bone cement 74 to conform to the inner mold 62 so as to form the desired inner surface 72 of the acetabular cup 70 . The load is maintained on the mold 60 for a sufficient period of time for the bone cement 74 to harden. The amount of time required for the bone cement 74 to harden depends on the particular type of cement used and other environmental conditions. For commercially available methyl methacrylate bone cement, the setting time will be approximately eight minutes.
The action of the inner mold 62 against the bone cement 74 causes the bone cement 74 to flow around the inner mold 62 so as to form a surface 72 conforming to the shape of the inner mold 62 and consisting essentially of hardened bone cement 74 . The surface 72 is thus a smooth, uniform hardened surface of bone cement 74 . However, due to the partially consolidated nature of the cancellous bone chips 73 , the bone cement 74 only penetrates the partially consolidated mass of cancellous bone chips 73 to a limited extent. While limited extrusions 75 of hardened bone cement may appear on the outer surface 71 , the outer surface 71 will consist essentially of the exposed surface of cancellous bone chips 73 . The outer surface 71 is thus of the appropriate shape to be received in the acetabulum of the patient and further presents a surface of exposed cancellous bone chips 73 which is conducive to bone ingrowth from the acetabulum into the composite acetabular allograft cup 70 .
While the shape of the acetabular cup 70 is essentially that of a hollow hemispherical dome, it may be noted from FIGS. 5 and 6 that a rim 76 may easily be formed in the acetabular cup 70 . Such a rim 76 may be desirable in certain applications and in other applications the rim 76 is not required.
The composite acetabular allograft cup 70 formed by the method of the present invention therefore comprises a hollow hemispherical dome 77 which may be surrounded by a rim 76 , as may be seen with reference to FIGS. 5, 7 , 8 and 9 . The composite acetabular allograft cup 70 presents an outer surface 71 comprised essentially of exposed cancellous bone chips 73 with minimal extrusions 75 of hardened bone cement 74 and an inner surface 72 comprised essentially of hardened bone cement 74 . For implantation of the composite acetabular allograft cup 70 , holes 78 may be drilled through the dome 77 . In some applications the holes 78 may be located in the rim 76 .
The use of the composite acetabular allograft cup 70 of the present invention may be described with reference to FIGS. 10 through 15. FIG. 10 shows a lateral cross section of the acetabulum 80 showing defects 81 in the acetabular wall. The defects 81 in the acetabular wall may include eroded portions of the wall, eroded or missing portions of the rim of the acetabulum 80 , and penetrations through the pelvic bone 82 .
FIG. 11 illustrates the same lateral cross section of the acetabulum 80 showing the acetabulum 80 prepared to receive the composite acetabular cup 70 by the removal of damaged portions of the acetabular wall. Deep defects 81 in the acetabular wall may be filled with cancellous bone chips 73 as shown in FIG. 12 .
The composite acetabular allograft cup 70 is employed in total hip replacement surgery generally in the following manner:
1. Holes 78 are drilled in the composite acetabular allograft cup 70 and the cup 70 is fixed in the acetabulum 80 with bone screws 83 .
2. In conventional implantation of the prosthetic hip joint, a metal cup is fixed in the acetabulum 80 This is not required in the surgical method of the present invention. Instead only the high density plastic liner 84 of the acetabular component is used. The plastic liner 84 is affixed to the composite acetabular allograft cup 70 with conventional bone cement.
3. The placement of the femoral component and the remainder of the surgery is conventional.
The sequences involved in the use of the acetabular cup 70 in total hip replacement surgery may be explained more fully with reference to FIGS. 10-15 as follows: (1) the acetabulum 80 is exposed, (2) the acetabulum is reamed, (3) the acetabular cup 70 is tested for fit in the acetabulum 80 , (4) the acetabular cup 70 is marked for drilling holes 78 for bone screws 83 , (5) the holes 78 are drilled in the acetabular cup 70 , (6) the acetabular cup 70 is affixed in place in the acetabulum 80 with bone screws 83 , (7) the high density plastic liner 84 is tested for fit in the acetabular cup 70 , (8) the femoral component is tested for fit in the plastic liner 84 , (9) a quantity of bone cement is placed in the acetabular cup 70 , and (10) the plastic liner 84 is pressed into the bone cement using an inserter.
FIG. 13 shows a lateral cross-section through the acetabulum 80 with the acetabular cup 70 fixed in the acetabulum 80 and the plastic liner 84 affixed in the acetabular cup 70 with bone cement. The remainder of the procedure is conventional.
The present invention has been described with reference to certain preferred and alternative embodiments which are intended to be exemplary only and not limiting to the full scope of the present invention as set forth in the appended claims. | A composite allograft press comprises a loading frame and a two piece mold to form an composite allograft and in particular an acetabular cup from impacted cancellous bone chips and cement. Pressure is applied by a manually operated lever through a rack-and-pinion gear mechanism to a plunger attached to one part of the mold. Compression load switches in-line with the plunger indicate the correct loading to the mold to produce a composite allograft in which the inner surface is smooth and comprised essentially of hardened bone cement material. The outer portion of the allograft may have limited cement extrusions but the exterior of the cup primarily shows exposed cancellous bone surface. In surgery a composite allograft; e.g., an acetabular cup, is fixed in the acetabulum with bone screws to fill an acetabular defect. A plastic liner is affixed with bone cement directly to the composite allograft cup to receive the femoral component. | 1 |
FIELD OF THE INVENTION
The present invention relates to the field of making soft paper from cellulose fibers and to apparatus and methods for making soft paper products.
BACKGROUND OF THE INVENTION
Amongst those in the paper industry the term "soft paper" is commonly given to a particular grade of paper used for absorbing purposes, such as tissues, drying cloths, paper toweling, napkins and handkerchiefs. These paper products, unlike their woven fabric counterparts, are intended for disposable use. Thus, while both paper and woven products desirably have rapid and effective absorption, soft feel, smooth structure, and good strength in both dry and wet states, it is the peculiar challenge of the paper industry to provide products embodying these characteristics at a price which makes their one-time use cost-effective.
The bulk of soft paper is manufactured by wet-forming. Wet-forming involves the use of a fiber suspension, usually in water, which is placed on a running wire or conveyor belt and subsequently dewatered and dried. High speed machines which acquire speeds of between 500 and 2,000 m/min. are commonly used, and a grammage between about 20 and about 30 g/m 2 is also common. In addition, the wet-formed paper is generally creped, usually by means of a so-called "Yankee cylinder," from which the paper web is scraped off after drying. Creping provides the paper with the necessary extensibility and softness.
Another method of forming soft paper is dry-forming. In dry-forming, dry paper-making pulp is fluffed to form fibers which are suspended in air. The air-borne fibers, without addition of water or other solvent, are deposited on an air pervious wire, and these fibers are bound together by means of a suitable chemical binding agent or agents which are added thereto. Because soft paper manufactured in this way is very bulky, i.e., has a very loose structure, the wire speed of dry-forming apparatus must be significantly reduced relative to the speed of wet-forming machines. Production rates of about 50 m/min. are common. As expected, manufacturing costs are very high because of the low throughput and cost of expensive binders. Consequently, paper manufactured by dry-forming is higher priced and occupies an uncompetitive position in the market place.
This is not to say, however, that price is the only consideration when choosing between soft paper manufactured by wet- and dry-forming. Dry-formed soft paper is a higher bulk than wet-formed paper. This results in a soft and smooth surface more pleasing to the touch. The reason for the higher bulk is that dry-formed paper fibers have not been softened in water and have not been bent down into the plane of the paper, nor have capillary forces been work during the removal of water therefrom. In contrast, wet-formed soft paper is stronger because of the amount of fiber binding which takes place when the fibers are in suspension and as they are dewatered. Furthermore, this strength is obtained without the necessity of additional binding agents which are required by dry-forming soft paper.
Despite significant improvements in the paper-making technology, a paper product having the softness of a dry-formed soft paper and the strength of a wet-formed soft paper, without the required use of expensive binding agents has gone unrealized.
It is therefore an object of the present invention to provide a soft paper product which has the softness of dry-formed paper and the strength and resiliency of wet-formed paper without binders.
It is also an object of the present invention to provide a method for forming a soft paper product having the softness of dry-formed soft paper and the strength of wet-formed soft paper, but without the use of binding agents.
It is further an object of the present invention to provide an apparatus for the production of a soft paper which has the strength of wet-formed soft paper and yet has the softness characteristic of dry-formed soft paper.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, there is provided a soft-paper article which includes a wet-formed layer of fiber material having a first and a second surface and a first dry-formed layer of fiber deposited upon the first surface of the wet-formed layer.
In accordance with another aspect of the present invention, there is provided a process for manufacturing soft paper from fibrous materials which includes the steps of wet-forming a first fiber layer, and depositing dry fibers on at least one surface of the first fiber layer such that a first dry-formed layer of dry fibers is fused and formed thereon.
In accordance with another aspect of the present invention, an apparatus is provided for making soft paper articles which includes a means for providing a suspension of wet fiber material to a running wire such that a first fiber layer is formed, at least one vacuum source arranged along the running wire disposed to at least partially dewater the first fiber layer and means for providing and depositing dry fibers onto at least one side of the first fiber layer.
The present invention is a combination of wet-forming and dry-forming technology whereby the advantages of both technologies are realized without the disadvantages that plague each. According to the present invention, air-borne fibers are deposited directly on a wet-formed layer while that layer is still wet. Between the two layers of fiber, binding takes place which ensures good cohesion of the layers and yield a particularly advantageous quality of soft paper. In a particularly preferred embodiment an additional layer of air-borne dry fibers is deposited on a second side of the wet-formed layer such that a sandwich construction is realized.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will be described in greater detail with reference to the accompanying drawing, wherein like members bear like reference numerals and wherein:
FIG. 1 is a diagrammatic view of the apparatus of the present invention.
DETAILED DESCRIPTION
Owing to the invention, the manufactured soft paper has a soft and smooth surface, higher bulk than wet-formed paper, and higher strength than dry-formed paper without the addition of chemical binding agents, softeners, adjuvants, etc. In addition, the soft paper product of the present invention has a high internal bond strength in spite of the absence of special binding agents.
In a preferred embodiment, the soft paper product of the present invention comprises a wet-formed layer of fiber material having a first and a second side and a first dry-formed layer of fiber material deposited upon at least one of the surfaces of the wet-formed layer of fiber material. The dry-formed layer should not be too thick and preferably every dry-formed fiber should be placed in intimate contact with the wet-formed layer, and a grammage of between about 2 and about 20 g/m 2 is preferred. While the sources of fiber material for both the wet-formed and dry-formed layers is variable, dry fibers taken from chemical pulp have been found to yield a surface of superior softness. The wet-formed layer should have a grammage of between about 10 and about 100 g/m 2 .
In a particularly preferred embodiment, the soft paper also contains a second dry-formed layer, falling within the description above, which is deposited upon a second surface of the wet-formed layer forming a sandwich thereof. It is not necessary that the paper products of the present invention be limited thereto. If a higher degree of thickness and/or strength is required, without sacrifice of the softness, repeating layers of wet-formed and dry-formed fiber material may be alternatively stacked and formed as described. In another embodiment, several layers of wet-formed fiber material are bound together and a layer of dry-formed fiber material is provided on each side of the plurality of wet-formed fiber layers.
According to another preferred embodiment of the present invention, a process is provided for manufacturing soft paper. The process involves wet-forming a first fiber layer and depositing dry fibers upon at least one surface of the first fiber layer such that a first dry-formed layer of dry fibers is fussed and formed thereon. In accordance with this process, a suspension of fibers, and preferably an aqueous suspension of fibers, is deposited onto a running wire and shaped as necessary to form a wet-formed layer, web, sheet, or non-woven mat. The wet-formed layer may, in a particularly preferred embodiment, be at least partially dewatered through use of a suction means prior to the application of dry fibers. At the time of the application of air-borne dry fibers, and in accordance with a particularly preferred embodiment, the wet-formed layer will have been dewatered to a dry solids content of between about 5 and 25%. The air-borne dry fibers are then deposited directly onto at least one side of the wet-formed layer, while it is still wet. These dry fibers thereby form a second fiber layer on the first fiber layer with binding occurring as a matter of natural consequence therebetween. The dry fibers are generally those exposed in a defibering device, such as, for example, handmill or coarse shredder, which are then refined by fluffing and transported to the first, wet-formed layer for deposition.
According to another preferred embodiment of the present invention, an apparatus for making soft paper is provided. The apparatus includes a means for providing suspension of wet fiber material to a running wire such that a first fiber layer is formed, at least one vacuum source arranged along said running wire exposed to at least partially dewater said first fiber layer, and means for providing and depositing dry fibers onto at least one side of said first fiber layer. The components for this apparatus are commonly known and used in the production of both wet- and dry-formed soft paper. However, to the applicants' knowledge, the technologies of the two apparatus have never been combined.
According to the present invention, a means for providing a suspension of wet fiber material to a running wire such that a first fiber layer is formed can include a head box and traditional wire or conveyor. In a particularly preferred embodiment, a paper making machine having an air-pervious wire is used. The apparatus will also include at least one vacuum source arranged along the running wire and exposed to at least partially dewater the wet-formed fiber layer. This can be accomplished through traditional suction boxes located beneath the wire. Finally, a means for providing and depositing dry fibers onto at least one side of the first fiber layer is provided. These dry fibers are deposited on the wet-formed layer by means of a forming box which is located above the wire and a vacuum box located beneath the wire. The dry fibers are exposed in a defibering device which can be, for example, hammermill or coarse shredder followed by a refiner for fluffing. The fibers are transported by means of a fan to a forming box mentioned above, which can be of the type shown in Swedish Patent Application 85.059186. Rejected discharge from the forming box can be recycled through a conduit after renewed defibering. Subsequently, a means for drying the soft paper product may be provided.
The present invention may be better understood by reference to the following embodiment which is merely an illustration of a preferred embodiment.
From a head box 1, a fiber suspension flows out onto a running wire 2 thereby forming a first fiber, wet fiber layer. The wire transports the wet-formed layer to suction boxes 3 located beneath the wire 2 whereby dewatering takes place. Subsequently, the wet-formed, partially dewatered layer is transported on the wire 2 to a location between the forming box 4 located above the wire 2 and a vacuum box 5 located beneath the wire 2. At this point air-borne dry fibers are deposited directly on the wet-formed layer through the forming box 4. These dry fibers thereby form a second fiber layer on the first, wet-formed layer. The dry fibers may be exposed, as described previously, in a defibering device 6, for example a hammermill or coarse shredder, followed by a refiner for fluffing. The fibers are transported by means of a fan 7 to the forming box 4. Rejected discharge from the forming box 4 can be transported through conduit 8 and recycled.
At the dry-forming stage, the dry fiber shall be well dispersed in air. For insuring this, the flow rate in the inlet to the forming box shall exceed 100 m/s. The distribution between the rejection flow through conduit 8 and the fiber flow dry-formed on the wet-formed layer shall be such that between about 25 and 100% of the incoming fibers are deposited directly on the wet-formed layer. When the dry fibers adhere to the wet-formed layer, the flow rate can be lower than 10 m/s, as the fiber concentration in air should not exceed about 10%.
FIG. 1 illustrates forming on a fourdrinier wire. However, alternately, forming can be carried out by means of a twin wire, in such a way that the dry fibers are deposited when one wire has left the wet-formed layer.
In a particularly preferred embodiment, a second apparatus is provided for forming soft paper with dry-formed fiber layers on both sides of the wet-layer. Dry fibers can be deposited on one side of the wet-formed layer while it is on the forming wire. Thereafter, the web thus formed is transferred to a second wire whereby dry fibers are deposited on the rear or on a second side of the wet-formed layer while it is still wet so that a third fiber layer is formed upon the wet-formed layer. A sandwich construction thus results.
The principles, preferred embodiments, and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein, however, is not to be construed as limited to the particular embodiments disclosed, since these are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the spirit and scope of the invention. | Soft paper from cellulose fibres is manufactured by wet-forming a first fibre layer. Thereafter air-borne dry fibres are deposited directly on one or both sides of the wet-formed layer while this is still wet, so that a second and possibly a third fibre layer are formed on the first one. Fibre bindings thereby arise between the layers. The wet-formed fibre layer gives the soft paper its strength, while the dry-formed fibers give a soft surface. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a manufacturing method of a magnetic recording medium suitable for pattern-processing a recording layer.
[0003] 2. Description of the Related Art
[0004] According to a prior art, in the manufacturing process of patterned recording media such as BPM (Bit Patterned Media) and DTM (Discrete Track Media), a resist layer is patterned into a prescribed pattern shape, and, based on the resist, the recording layer is processed into the pattern shape by dry etching.
[0005] In recent years, as a formation method of a pattern of convex and concave parts in the resist layer to be an etching mask, an imprint method, in which a mold is compressed to the resist layer to form a pattern, has been used frequently because it gives an excellent productivity. But, according to the method, the Duty cycle (the ratio occupied by the convex part in the pattern of convex and concave parts) of the resist after the pattern formation by the mold is less than 60%, and, moreover, after passing through the process of resist processing for removing the resist left at the bottom part, the sidewall of the convex part is simultaneously etched to further lower the Duty cycle. Moreover, the resist is also etched and shrunk in the process of recording layer processing using the resist as an etching mask, and, therefore, the Duty cycle of the recording layer pattern obtained further lowers than that of the resist pattern. Since resists generally used are heat-curable, they are easily shrunk by the heat ejected from plasma etc. at the time of the processing to generate easily the lowering of the Duty cycle and processing variation.
[0006] In contrast to this, in order to improve the Duty cycle of the processed pattern of a recording layer, there is a method of forming a multilayer hard mask under the resist layer (see Japanese Patent Application Laid-open Publication No. 2005-50468). The method makes use of a carbon film to be an etching mask for the recording layer and a silicide or metal film having a large etching selectivity relative to the carbon film for processing the carbon film, as a multilayer hard mask over the recording layer.
[0007] The method shown in Japanese Patent Application Laid-open Publication No. 2005-50468 makes use, however, of reactive etching using a fluorinated gas as a reactive gas for processing the silicide and the metal films. Through the etching process by the fluorinated gas, fluorine remains on the substrate or substrate holder, which causes the corrosion of a magnetic film being the recording layer to be induced.
SUMMARY OF THE INVENTION
[0008] The present invention aims at providing a manufacturing method of a magnetic recording medium capable of reducing the deterioration of the recording layer and improving the Duty cycle of the recording layer.
[0009] One aspect of the present invention is a manufacturing method of magnetic recording medium that processes a recording layer by etching, comprising the steps of: depositing a material having an etching rate by the etching lower than that of the recording layer, on a resist pattern formed on a workpiece containing the recording layer, and processing the recording layer into the same shape as the resist pattern by the etching using the resist pattern and the material as a mask.
[0010] The magnetic recording medium patterned by the above method has an improved Duty cycle of the recording layer pattern, as compared with a medium patterned by a processing process using a resist mask alone. That is, the land width of the recording layer contributing to magnetic recording becomes wider, which leads to the improvement of the recording density of the magnetic recording medium.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIGS. 1A to 1F are drawings showing the flow of substrate treatment process from resist processing to mask removal being an embodiment of the present invention.
[0012] FIG. 2 is a drawing showing a constitution example of manufacturing equipment for executing the flow in FIG. 1 .
[0013] FIG. 3 is a drawing showing a SEM (scanning electron microscope) photograph of a workpiece before the process of resist processing according to an embodiment of the present invention.
[0014] FIG. 4 is a drawing showing a SEM photograph of a workpiece after the process of resist processing according to an embodiment of the present invention.
[0015] FIG. 5 is a drawing showing a SEM photograph of a workpiece after the deposition of a protective film according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0016] FIGS. 1A to 1F show the flow of substrate treatment processes from the resist processing to the mask removal being an embodiment of the present invention, and FIG. 2 shows an example of the manufacturing apparatus of a magnetic recording medium capable of executing the flow.
[0017] The example in FIG. 2 has such a construction that a process chamber P 1 for executing the process of resist processing, a process chamber P 2 for executing the process of resist protective film deposition, a process chamber P 3 for executing the process of resist protective film processing, a process chamber P 4 for executing the process of recording layer processing, and a process chamber P 5 for executing the process of mask removal are connected hermetically via a gate valve. As described above, substrate treatments from the resist processing to the mask removal are desirably performed in inline apparatus of a vacuum one loop, but treatments may be performed in each independent vacuum chamber along such a flow. Moreover, another process chamber may be connected midway, or before or after these.
[0018] In the process of resist processing, the resist processing treatment is performed for a workpiece 10 by, for example, etching in the process chamber P 1 . Accordingly, the process chamber P 1 is constituted so as to be capable of performing, for example, reactive ion etching (RIE). The workpiece 10 shown in FIG. 1A is formed by laminating sequentially a lower layer 12 , a recording layer 13 and a resist 14 on a substrate 11 , wherein a pattern of convex and concave parts (resist pattern) is previously formed in the resist 14 by an imprint method. That is, the substrate 11 having the resist 14 formed on the recording layer 13 is prepared, the resist 14 having an intended resist pattern formed. In the example in FIG. 1A , there is formed a pattern of concave and convex parts for forming the recording layer 13 of a discrete type having groove-shaped concave parts in parallel with each other.
[0019] For the substrate 11 , the lower layer 12 and the recording layer 13 , known materials can be used, and, as the substrate 11 , for example, a glass substrate or an aluminum substrate having a diameter of 2.5 inches (65 mm) can be used. The lower layer 12 is constituted by laminating, for example, a soft magnetic layer containing a soft magnetic material such as an Fe alloy and a Co alloy, and an underlayer containing Ru, Ta etc. for vertically orienting the axis of easy magnetization of the recording layer 13 , etc. The recording layer 13 is a layer that is magnetized vertically relative to the substrate 11 , and contains a Co alloy etc.
[0020] Specifically, in the process of resist processing, the resist 14 remaining at the pattern bottom part of the resist pattern formed in the resist 14 by etching is removed by the process chamber P 1 ( FIG. 1B ). The removing method of the resist can be adopted corresponding to the kind of the resist 14 , and is not particularly limited in the present invention. For example, a reactive ion etching using an oxygen gas plasma can be used. Meanwhile, this process is not indispensable to the present invention, and a resist pattern exposing the recording layer 13 at the concave part may be formed by dry etching etc. other than the imprint method. That is, the workpiece 10 , in which the recording layer 13 is exposed at the bottom of the resist pattern formed in the resist 14 , has only to be prepared before performing the process of resist protective film deposition and subsequent processes in FIG. 2 .
[0021] Next, in the process of resist protective film deposition, a resist protective film 15 is formed on the workpiece 10 having been subjected to the process of resist processing by, for example, sputtering, CVD (Chemical Vapor Deposition) etc. by the process chamber P 2 ( FIG. 1C ). Accordingly, the process chamber P 2 is constituted so that it can perform a film-forming treatment such as sputtering and CVD.
[0022] In the present embodiment, in performing the process of resist protective film deposition, the consistency of the material of the resist 14 with the material of the resist protective film 15 , and the film-forming condition are selected so that the film-forming rate to the resist pattern head part PH becomes higher than that to the resist pattern bottom part PB. From this standpoint, the film is preferably formed by sputtering without applying bias power to the substrate. For example, when a carbonaceous resist is adopted as the resist 14 , for example, a carbon film containing carbon as a main ingredient (including a carbon-based film such as diamond-like carbon) may be used as the resist protective film 15 to be formed thereon. As described above, the use of the above-described carbon film as the resist protective film 15 causes the carbon film to grow and accumulate on a resist pattern sidewall PS, too, so as to enwind the resist pattern, and, as the result, causes the height and Duty cycle of the etching mask to increase by the amount of the resist protective film 15 than the sole resist mask (resist 14 shown in FIG. 1B ).
[0023] As to the material of the resist protective film 15 , a material, which can give a selection ratio relative to the recording layer 13 in the process of recording layer processing to be described later, is used. In the present embodiment, since ion beam etching is performed in the process of recording layer processing, a material having an etching rate lower than that of the recording layer 13 is used. That is, as the material of the resist protective film 15 , there may be used a material having an etching rate by the etching used in the process of recording layer processing lower than that of the recording layer 13 to be processed in the process. The above-described carbon film is preferable because it satisfies the condition of the selection ratio and has a higher resistance relative to the ion beam than the resist. The carbon film as the resist protective film 15 is produced by a sputtering method using a carbon-containing target, a plasma CVD method using a carbon hydride gas, etc. In any case, it is possible to lead to a state where the deposition amount on the pattern head part is larger by the combination with the carbonaceous resist as the resist 14 , and it is preferable to form the film in a state where no bias voltage is applied to the substrate, because the above-described state becomes remarkable.
[0024] Next, in the process of resist protective film processing, etching processing is performed on the workpiece 10 having been subjected to the process of resist protective film deposition by etching etc. by the process chamber P 3 to thereby remove the resist protective film accumulated at the pattern bottom part ( FIG. 1D ). Accordingly, the process chamber P 3 is constituted so that, for example, it can perform the reactive ion etching (RIE). In the present embodiment, since the formation amount of the resist protective film 15 at the resist pattern head part PH is larger than that at the resist pattern bottom part PB, the height and the width of the carbon protective film 15 after having removed the carbon protective film 15 at the resist pattern bottom part PB are still larger than those of the resist 14 after the process of resist processing (resist 14 in FIG. 1B ).
[0025] Next, in the process of recording layer processing, the recording layer 13 is etched by using the resist 14 and resist protective film 15 as a mask M by the process chamber P 4 to process the recording layer 13 into the same shape as the resist pattern ( FIG. 1E ). Accordingly, the process chamber P 4 is constituted so that it can perform, for example, the reactive ion etching (RIE). No particular limitation is imposed on the etching method if the method can give the selection ratio relative to the mask M, and for example, the ion beam etching can be used. For example, when the above-described carbon film is used as the resist protective film 15 , a carbon-based film having a high resistance against the ion beam etching in addition to giving a volume increase in the mask M, is used as the mask. Accordingly, the shrinkage and recession of the mask in the process of recording layer processing are small to thereby improve the Duty cycle and the shape such as the degree of verticality of the sidewall after the recording layer processing, as compared with the case where the resist alone is used.
[0026] After that, in the process of mask removal, the mask M is removed by the process chamber P 5 ( FIG. 1F ). Accordingly, the process chamber P 5 is constituted so that it can perform, for example, the reactive ion etching (RIE). When the carbon film is adopted as the resist protective film 15 , it can be removed along with the resist 14 by the dry etching using the same oxygen gas plasma.
[0027] Heretofore, the first embodiment has been explained, but the application of the present invention is not limited to the above embodiment. For example, in the process of resist protective film deposition, if the deposition amount onto the pattern bottom part PB of the resist protective film 15 is extremely smaller than that onto the pattern head part PH, the process of recording layer processing may be performed while omitting the process of resist protective film processing.
[0028] Moreover, a recording layer-protecting layer for protecting the recording layer 13 , for example, a silicon film having a thickness of about 3 nm may be inserted between the recording layer 13 and the resist 14 .
[0029] Next, an example of the present invention will be explained.
[0030] First, through the use of the manufacturing apparatus shown in FIG. 2 , in the process chamber P 1 , a mixed gas of oxygen and argon gases was caused to discharge by an ICP (Inductively Coupled Plasma) unit, pulse DC bias was applied to the substrate, and, under conditions shown below, the reactive etching was performed on the workpiece 10 as shown in FIG. 1A . This removes the resist 14 left at the bottom part of the resist pattern.
Processing Condition of Resist:
[0031] oxygen gas flow rate: 3 sccm,
[0032] Ar gas flow rate: 30 sccm,
[0033] pressure: 1 Pa,
[0034] discharge power: 200 W,
[0035] substrate bias: −30 V, and
[0036] etching time: 10 seconds
[0037] Next, in the process chamber P 2 , as shown in FIG. 1C , a carbon film as the resist protective film 15 was formed on the processed resist 14 by magnetron sputtering.
Film-Forming Condition:
[0038] Ar gas flow rate: 100 sccm,
[0039] pressure: 0.7 Pa,
[0040] discharge power: 1000 W,
[0041] substrate bias: not applied, and
[0042] film-forming time: 25 seconds
[0043] Next, in the process chamber P 3 , as shown in FIG. 1D , the carbon film accumulated at the resist pattern bottom part of the resist 14 was removed. Specifically, the mixed gas of oxygen and argon gases was discharged by an ICP unit, and pulse DC bias was applied to the substrate to perform reactive etching on the workpiece 10 as shown in FIG. 1C .
Etching Condition:
[0044] oxygen gas flow rate: 3 sccm,
[0045] Ar gas flow rate: 30 sccm,
[0046] pressure: 1 pa,
[0047] discharge power: 200 w,
[0048] substrate bias: −30 V, and
[0049] etching time: 10 seconds
[0050] Next, in the process chamber P 4 , through the use of the pattern of the processed mask M, an ion beam etching (IBE) unit was used to discharge Ar gas, and the Ar ions were accelerated by a grid to perform ion beam etching on the recording layer 13 .
Ion Beam Condition:
[0051] Ar gas flow rate: 5 sccm,
[0052] pressure: 0.04 Pa,
[0053] discharge power: 200 W,
[0054] ion acceleration voltage: 1000 V,
[0055] ion beam power: 150 W, and
[0056] etching time: 20 seconds
[0057] Next, in the process chamber P 5 , the mask M left on the workpiece 10 , having been subjected to recording layer processing, was removed. Specifically, a mixed gas of oxygen and argon gases was discharged by the ICP unit to remove the mask M by reactive etching.
Etching Condition:
[0058] oxygen gas flow rate: 3 sccm,
[0059] Ar gas flow rate: 30 sccm,
[0060] pressure: 1 Pa,
[0061] discharge power: 200 W,
[0062] substrate bias: −50 V, and
[0063] etching time: 30 seconds
[0064] FIG. 3 is a SEM photograph of the workpiece before the process of resist processing, FIG. 4 is a SEM photograph of the workpiece after the process of resist processing, and FIG. 5 is a SEM photograph of the workpiece after the deposition of the resist protective film. It can be confirmed that the resist at the pattern bottom part is removed by the process of resist processing, and that the height and width of the resist 14 are shrunk considerably ( FIG. 4 ). After depositing a carbon film as the resist protective film 15 on the same by sputtering, the mask increased to 48 nm in the height and to 18 nm in the width, while on the other hand, the thickness of the film deposited at the pattern bottom was only 7 nm, which shows that the resist protective film 15 is deposited by surrounding the resist 14 . It was confirmed that the process of resist protective film deposition was able to largely improve the height and Duty cycle of the mask ( FIG. 5 ). | The present invention provides a manufacturing method of a magnetic recording medium capable of reducing the deterioration of a recording layer and improving the Duty cycle of the recording layer. An embodiment of the present invention is a manufacturing method of a patterned recording medium such as BPM (Bit Patterned Media) and DTM (Discrete Track Media). The manufacturing method has a deposition step of depositing a resist protective film on a resist pattern formed on a workpiece containing a recording layer, and a recording layer processing step of processing the recording layer into a pattern shape by dry etching using the resist pattern and the resist protective film as a mask. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional Patent Application Ser. No. 60/655,289, filed Feb. 22, 2005, which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to systems and methods for drilling and completing a wellbore. More particularly, the invention relates to systems and methods for mitigating trouble zones in a wellbore in a managed pressure condition and completing the wellbore in the managed pressure condition.
[0004] 2. Description of the Related Art
[0005] Historically, wells have been drilled with a column of fluid in the wellbore designed to overcome any formation pressure encountered as the wellbore is formed. This “overbalanced condition” restricts the influx of formation fluids such as oil, gas or water into the wellbore. Typically, well control is maintained by using a drilling fluid with a predetermined density to keep the hydrostatic pressure of the drilling fluid higher than the formation pressure. As the wellbore is formed, drill cuttings and small particles or “fines” are created by the drilling operation. Formation damage may occur when the hydrostatic pressure forces the drilling fluid, drill cuttings and fines into the reservoir. Further, drilling fluid may flow into the formation at a rate where little or no fluid returns to the surface. This flow of fluid into the formation can cause the “fines” to line the walls of the wellbore. Eventually, the cuttings or other solids form a wellbore “skin” along the interface between the wellbore and the formation. The wellbore skin restricts the flow of the formation fluid during a production operation and thereby damages the well.
[0006] Another form of drilling is called managed pressure drilling. An advantage of managed pressure drilling is the ability to make bottom hole pressure adjustments with minimal interruptions to the drilling progress. Another related drilling method of managed pressure drilling is underbalanced drilling. In this drilling method, the column of fluid in the wellbore is designed to be less than the formation pressure encountered as the wellbore is formed. Typically, well control is maintained by using a drilling fluid with a predetermined density to keep the hydrostatic pressure of the drilling fluid lower than the formation pressure. As the wellbore is formed, drill cuttings and small particles or “fines” are created by the drilling operation and circulated out of the wellbore resulting in minimal formation damage.
[0007] Managed pressure drilling and underbalanced drilling maximizes the production of the well by reducing skin effect and/or formation damage during the drilling operation. However, the maximization of production is negated when the well has to be killed in order to mitigate a trouble zone encountered during the managed pressure or underbalanced drilling operation. Further, the maximization of production is negated when the well has to be killed in order to complete the wellbore after the drilling operation. Presently, snubbing is a method for tripping a drill string in a constant underbalanced state. Snubbing removes the possibility of damaging the formation, but increases rig up/rig down and tripping times, adding to the operational expense. In addition, the snubbing unit cannot seal around complex assemblies, such as a solid expandable drilling liner which is typically used to mitigate a trouble zone encountered during a drilling operation. Further snubbing units cannot seal around slotted liners or conventional sand screens which are typically used in completing a wellbore.
[0008] There is a need, therefore, for an effective method and system to mitigate trouble zones encountered during an underbalanced or managed pressure drilling operation. There is a further need, therefore, for an effective method and system to complete the wellbore in an underbalanced or managed pressure condition.
SUMMARY OF THE INVENTION
[0009] The present invention generally relates to methods and systems for mitigating trouble zones in a wellbore in a preferred pressure condition and completing the wellbore in the preferred pressure condition. In one aspect, a method of reinforcing a wellbore is provided. The method includes locating a valve member within the wellbore for opening and closing the wellbore. The method further includes establishing a preferred pressure condition within the wellbore and closing the valve member. The method also includes locating a tubular string having an expandable portion in the wellbore and opening the valve member. Additionally, the method includes moving the expandable portion through the opened valve member and expanding the expandable portion in the wellbore at a location below the valve member.
[0010] In another aspect, a method of forming a wellbore is provided. The method includes separating the wellbore into a first region and a second region by closing a valve member disposed in the wellbore. The method also includes reducing the pressure in the first region and lowering a tubular string having an earth removal member and an expandable portion into the first region of the wellbore to point proximate the valve member. The method further includes establishing and maintaining a preferred pressure condition in the wellbore and opening the valve member. Additionally, the method includes moving the earth removal member and the expandable portion through the opened valve member and forming the wellbore.
[0011] In yet another aspect, a system for drilling a wellbore is provided. The system includes a tubular string having an earth removal member and an expandable portion. The system also includes a valve member located within the wellbore for substantially opening and closing the wellbore. Additionally, the system includes a fluid handling system for maintaining a portion of the wellbore in one of a managed pressure condition and an underbalanced pressure condition.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of 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.
[0013] FIG. 1 is a view of a drilling assembly being lowered in a wellbore on a drill string.
[0014] FIG. 2 is a view of the wellbore with a valve member in a closed position.
[0015] FIG. 3 illustrates the drilling assembly forming another section of the wellbore during an underbalanced or a managed pressure drilling operation.
[0016] FIG. 4 illustrates the drilling assembly forming another section of the wellbore after an expandable portion has isolated a trouble zone from the surrounding wellbore.
[0017] FIG. 5 illustrates the placement of a second expandable portion at another trouble zone.
[0018] FIG. 6 illustrates a portion of the wellbore being formed by drilling with a string of casing.
[0019] FIG. 7 illustrates a completed wellbore with an expandable filter member.
[0020] FIGS. 8A-8D illustrate different forms of the expandable portion.
DETAILED DESCRIPTION
[0021] In general, the present invention relates to systems and methods for completing a wellbore in a preferred pressure condition in order to reduce wellbore damage. As will be described herein, the systems and methods are employed in a wellbore having a preferred pressure condition, such as an underbalanced or managed pressure condition. It must be noted that aspects of the present invention are not limited to these conditions, but are equally applicable to other types of wellbore conditions. Additionally, the present invention will be described as it relates to a vertical wellbore. However, it should be understood that the invention may be employed in a horizontal or deviated wellbore without departing from the principles of the present invention. To better understand the novelty of the apparatus of the present invention and the methods of use thereof, reference is hereafter made to the accompanying drawings.
[0022] FIG. 1 is a view of a drilling assembly 100 being lowered in a wellbore 10 on a drill string 105 . The drilling assembly 100 includes a drill bit 110 or other earth removal member, a first carrying assembly 115 with an expandable portion 125 and a second carrying assembly 120 with an expandable portion 130 . As illustrated, the wellbore 10 is lined with a string of steel pipe called casing 15 . The casing 15 provides support to the wellbore 10 and facilitates the isolation of certain areas of the wellbore 10 adjacent hydrocarbon bearing formations. The casing 15 typically extends down the wellbore 10 from the surface of the well to a designated depth. An annular area 20 is thus defined between the outside of the casing 15 and the wellbore 10 . This annular area 20 is filled with cement 25 pumped through a cementing system (not shown) to permanently set the casing 15 in the wellbore 10 and to facilitate the isolation of production zones and fluids at different depths within the wellbore 10 .
[0023] At the surface of the wellbore 10 , a rotating control head 75 is disposed on a blow out preventer (BOP) stack 80 . Generally, the rotating control head 75 isolates pressurized annular returns and diverts flow away from the surface of the wellbore 10 to a choke manifold (not shown) and a separator (not shown). The rotating control head 75 , which is mounted on top of the BOP stack 80 , seals the drill string 105 creating a pressure barrier on the annulus side of the drill string 105 while the drill string 105 is being tripped in or out of the wellbore 10 or while it is being rotated during drilling operations. Additionally, the rotating control head 75 and the choke manifold are used to manage the wellbore's annular pressure, such as in a managed pressure condition or an underbalanced pressure condition.
[0024] During the underbalanced drilling operation, the reservoir fluids are allowed to flow. Therefore a surface pressure is ever present in the annulus formed between the drill string 105 and the casing 15 . The rotating control head 75 is used to control the pressure at the surface of the wellbore 10 . As tripping begins, and the drill string 105 is stripped through the rotating control head 75 , the pressure must be managed to prevent well pressures uncontrollably forcing the drill string out 105 of the wellbore in a pipe-light situation. Generally pipe-light occurs at the point where the formation pressure across the pipe cross-section creates an upward force sufficient to overcome the downward force created by the pipe's weight.
[0025] A downhole deployment valve 50 is disposed at the lower end of the casing 15 . The downhole deployment valve 50 is commonly used to shut-in oil and gas wells. The downhole deployment valve 50 may be installed in the casing 15 as shown in FIG. 1 or the downhole deployment valve 50 may be installed on a tie-back string which can be retrieved following the drilling operation. Generally, the downhole deployment valve 50 is configured to selectively block the flow of formation fluids upwardly through the casing 15 should a failure or hazardous condition occur at the well surface. Additionally, the downhole deployment valve 50 allows a wide range of systems and bottom hole assemblies to be safely and effectively deployed in an underbalanced or a mangaged pressure drilling operation. Typically, the downhole deployment valve 50 is maintained in an open position by the application of hydraulic fluid pressure transmitted to an actuating mechanism. The actuating mechanism (not shown) is charged by application of hydraulic pressure. The hydraulic pressure is commonly a clean oil supplied from a surface fluid reservoir through a control line. A pump (not shown) at the surface of the wellbore 10 delivers regulated hydraulic fluid under pressure from the surface of the wellbore 10 to the actuating mechanism through the control line. Typically, the bore through the downhole deployment valve 50 is equal to or greater than the drift diameter of the casing 15 when the downhole deployment valve 50 is in the open position.
[0026] As illustrated in FIG. 1 , the drilling assembly 100 is lowered into the wellbore 10 on the drill string 105 to a point proximate the downhole deployment valve 50 . Pressure within the drill string 105 is controlled by closing an inner diameter of the drill string using a valve member within the drill string or a retrievable plug. Thereafter, the downhole deployment valve 50 is closed as illustrated in FIG. 2 by applying hydraulic pressure from the surface fluid reservoir through the control line.
[0027] After the downhole deployment valve 50 is closed, the wellbore 10 is separated into a first region 85 and a second region 90 . The wellbore pressure in the first region is then reduced to substantially zero by manipulating the rotating control head 75 and the choke manifold system. In one embodiment, the downhole deployment valve 50 is equipped with downhole sensors that transmit an electrical signal to the surface, allowing measurement and reading of real-time downhole pressures.
[0028] When the wellbore pressure in the first region 85 is reduced to substantially zero, the balance of the drill string 105 is tripped out of the wellbore 10 in a similar manner as the procedure for tripping pipe in a dead well. During the trip into the wellbore 10 , the drill string 105 is rerun to a depth directly above the downhole deployment valve 50 , where a pipe-heavy condition exists. Subsequently, pressure is applied to the wellbore 10 to equalize the pressure in the first region 85 and the second region 90 . When the pressures in the regions 85 , 90 are substantially equal, hydraulic pressure from the surface fluid reservoir is applied through the control line to open the downhole deployment valve 50 , thereby opening the pathway into region 90 of the wellbore 10 .
[0029] FIG. 3 illustrates the drilling assembly 100 forming another section of the wellbore 10 during an underbalanced or a managed pressure drilling operation. Generally, the wellbore 10 is formed by rotating the drill bit 110 while urging the drilling assembly 100 downward away from the mouth of the wellbore 10 . Typically, the drill bit 110 is rotated by the drill string 105 or by a downhole motor arrangement (not shown).
[0030] The wellbore 10 will be formed by the drilling assembly 100 until the drilling assembly 100 encounters a trouble zone 160 . The trouble zone is a section or zone of the wellbore that negativity affects the drilling operation and/or subsequent production operation. For instance, the trouble zone may be a permeable pay zone which drains the drilling fluid from the wellbore 10 . The trouble zone may also be a high pressure water flow zone which communicates high pressure water into the wellbore 10 . The trouble zone may consist of a loss circulation zone that causes sloughing intervals or pressure transistions.
[0031] Once the trouble zone 160 is encountered during the drilling operation, the trouble zone 160 must be mitigated in order to effectively continue the drilling operation. In one embodiment, the trouble zone is mitigated by isolating the trouble zone from the wellbore by placing the expandable portion 125 over the trouble zone 160 . The expandable portion 125 may be an expandable clad member, an expandable liner as shown in FIGS. 8A-8C , or any other form of expandable member.
[0032] As illustrated in FIG. 3 , the drilling assembly 100 is positioned in the wellbore 10 such that the first carrying assembly 115 is positioned proximate a trouble zone 160 . In one embodiment, the portion of the wellbore 10 by the trouble zone 160 is enlarged or under-reamed by an under-reamer (not shown) or an expandable drill bit (not shown) prior to placing the carrying assembly 115 proximate the trouble zone 160 . Thereafter, the carrying assembly 115 is activated and the expandable portion 125 is expanded radially outward into contact with the under-reamed portion of the wellbore 10 . Next, the expandable portion 125 is released from the carrying assembly 115 and the drilling operation is continued.
[0033] The expandable portion 125 isolates the trouble zone 160 without loss of wellbore diameter. In other words, after expansion of the expandable portion 125 , the inner diameter of the expandable portion 125 is greater than or equal to the inner diameter of the casing 15 , thereby resulting in a monobore configuration. Further, the expandable portion 125 may have an anchoring member on an outside surface to allow the expandable portion 125 to grip the wellbore 10 upon expansion of the expandable portion 125 . The expandable portion 125 may also have a seal member disposed on an outside surface to create a sealing relationship with the wellbore 10 upon expansion of the expandable portion 125 . Additionally, the expandable portion 125 may be set in the wellbore 10 with or without the use of cement.
[0034] The carrying assembly 115 may include a hydraulically activated expansion member or another type of expansion member known in the art such as solid swage or a rotary tool. Additionally, the expansion member may expand the expandable member 125 in a top to bottom expansion or in a bottom to top expansion without departing from principles of the present invention.
[0035] In one embodiment, the expandable portion 125 is a pre-shaped or profiled tubular. After the carrying assembly 115 is positioned proximate the trouble zone 160 , the carrying assembly 115 applies an internal pressure to the expandable portion 125 to substantially deform or reshape the expandable portion 125 to its original round shape and into contact with the wellbore 10 . Thereafter, a rotary expansion tool or another type of expansion tool may be used to further radially expand the expandable portion 125 .
[0036] FIG. 4 illustrates the drilling assembly 100 forming another section of the wellbore 10 after the expandable portion 125 has been placed in the wellbore 10 . As shown, the drilling assembly 100 is urged further into the wellbore 10 and the expandable portion 130 moves through the inner diameter of the expandable portion 125 . The drilling assembly 100 continues to form the wellbore 10 until another trouble zone 165 is encountered. At that point, the trouble zone 165 is mitigated by isolating the trouble zone 165 from the wellbore by placing the expandable portion 130 over the trouble zone 165 as illustrated in FIG. 5 .
[0037] Similar to the process described above, the carrying assembly 120 is located in the wellbore 10 such that the expandable portion 130 is positioned proximate the trouble zone 165 . Thereafter, an expansion member in the carrying assembly 120 is activated and the expandable portion 130 is expanded radially outward into contact with the under-reamed portion of the wellbore 10 and then the expandable portion 130 is released from the carrying assembly 120 . Similar to expandable portion 125 , the expandable portion 130 isolates the trouble zone 165 without loss of wellbore diameter. In other words, after expansion of the expandable portion 130 , the inner diameter of the expandable portion 130 is greater than or equal to the inner diameter of the casing 15 and the inner diameter of the expandable portion 125 , thereby resulting in a monobore configuration.
[0038] After both expandable portions 125 , 130 have been deployed, the drill string 105 is retrieved from the wellbore 10 until the lower end of the drilling assembly 100 is above the deployment valve 50 . The deployment valve 50 is then closed and the annular seal is then disengaged. Thereafter, the drill string may be removed from the wellbore 10 . Although the deployment of only two expandable portions has been described, more than two may be drilled in and deployed using the steps described without departing from principles of the present invention. Additionally, the Figures illustrate the drill bit 110 and the expandable portions 125 , 130 lowered on the drill sting 105 at the same time. It should be understood, however, that the drill bit 110 and the expandable portions 125 , 130 may be used independently without departing from principles of the present invention. In other words, the drill bit 110 may be used to form the wellbore 10 and then removed from the wellbore 10 while maintaining the preferred pressure condition. Thereafter, the expandable portion 125 may be lowered and disposed in the wellbore 10 as described herein while maintaining the preferred pressure condition.
[0039] In another embodiment the drill string 105 is deployed as described above until the first expandable portion 125 deployment is complete. At that point the drill string 105 is retrieved from the wellbore 10 until the lower end of the drill string 105 is above the deployment valve 50 . The deployment valve 50 is then closed and the annular seal is then disengaged. Retrieval of the drill string 105 is then continued until the carrying assembly 115 of the drill string 105 is accessible. A second expandable portion 130 is then affixed to the carrying assembly 115 .
[0040] The deployment valve 50 is then closed and the drill string 105 is reinserted into the wellbore 10 until at least the drilling assembly 100 is within the wellbore 10 . The annular seal is engaged between the wellbore inner diameter and the drill string 105 and the deployment valve 50 is opened. The drill string 105 is progressed into the wellbore through the deployment valve 50 and the drill bit 110 engaged in drilling below the previously deployed expandable portion 125 . The second expandable portion 130 is deployed proximate a second formation requiring control when drilling has progressed to that point. Following deployment of the second expandable portion 130 drilling may progress further or the drilling assembly 100 may be retrieved as previously described herein.
[0041] FIG. 6 illustrates a portion of the wellbore 10 formed by drilling with a string of casing 175 . Another type of trouble zone is a sloughing shale zone. One cause of unstable hole condition can occur in certain formations when the hydrostatic pressure of the fluid column is not sufficient to hold back the formation, resulting in sloughing of the wall of the wellbore 10 . For this reason sloughing formations, especially shale sections, are somewhat common in underbalanced drilling operations. There are several different methods of remediating these type of trouble zones, such as managed pressure drilling techniques, solid expandable liners (either tied-back or not) through the use of conventional liners, or by drilling with casing or liners. Each method has its own limitations. However, drilling with casing technology has been used for both drilling through problem formations and ensuring the casing or liner can be set on bottom through unstable hole conditions.
[0042] Drilling with casing (or liners) are useful tools for drilling in difficult drilling conditions. Drilling with casing can be a relatively simple operation if the operator knows of a problem zone. For instance, a conventional assembly can be used to drill the wellbore 10 to a point just above the trouble zone. Thereafter, the conventional assembly may be removed and a casing string 175 with a drill bit 180 attached is introduced into the wellbore 10 . Similar to the procedure previously discussed, the casing string 175 and the drill bit 180 are lowered into the wellbore 10 on the drill string 105 to a point proximate the downhole deployment valve 50 . Thereafter, the downhole deployment valve 50 is closed. Next, the wellbore pressure in the first region above the valve 50 is reduced to substantially zero by manipulating the rotating control head 75 and the choke manifold system. When the wellbore pressure in the first region 85 is reduced to substantially zero, the balance of the drill string 105 is tripped out of the wellbore 10 in a similar manner as the procedure for tripping pipe in a dead well. During the trip into the wellbore 10 , the drill string 105 is rerun to a depth directly above the downhole deployment valve 50 , where a pipe-heavy condition exists. Subsequently, pressure is applied to the wellbore 10 to equalize the pressure in the first region and the second region below the valve 50 . When the pressures in the regions are substantially equal, hydraulic pressure from the surface fluid reservoir is applied through the control line to open the downhole deployment valve 50 , thereby opening the pathway into the region of the wellbore 10 below the valve 50 . Then the casing string 175 and the drill bit 180 are lowered into the wellbore 10 past the expandable portions 125 , 130 to form another portion of the wellbore 10 .
[0043] Generally, drilling with casing entails running the casing string 175 into the wellbore 10 with the drill bit 180 attached. The drill bit 180 is operated by rotation of the casing string 175 from the surface of the wellbore 10 . Once the wellbore 10 is formed, the attached casing string 175 is cemented in the wellbore 10 . Thereafter, a drilling assembly (not shown) may be employed to drill through the drill bit 180 at the end of the casing string 175 and subsequently form another portion of the wellbore 10 .
[0044] In drilling the wellbore 10 , the drilling assembly 100 with a directional drilling member (not shown) is tripped into the wellbore 10 through the valve 50 (and hole angle is built to horizontal). The reservoir is drilled underbalanced to a total depth. Pressure while drilling and gamma ray sensors in the guidance system, in addition to the normal directional tool face, inclination and azimuth readings, aid in maintaining proper underbalance margin and geologic settings. Multiphase flow modeling prior to and during the drilling operation insures desired equivalent circulating density (ECD) and sufficient circulation rates required for cuttings removal and good hole cleaning during Under Balanced Drilling operations. Additionally, fluid density may be adjusted, as can the injection rates of nitrogen and liquid to achieve the desired mixture density.
[0045] FIG. 7 illustrates the wellbore 10 with an expandable filter member 185 or a screen. For purposes of sand control, the expandable filter member 185 commonly referred to as an Expandable Sand Screen (ESS®) is useful in controlling sand and enhancing the productivity of both vertical and horizontal wells. In a similar manner as previously discussed, the expandable filter member 185 is lowered into the wellbore 10 on the drill string 105 to a point proximate the downhole deployment valve 50 . Thereafter, the downhole deployment valve 50 is closed. Next, the wellbore pressure in the first region above the valve 50 is reduced to substantially zero by manipulating the rotating control head 75 and the choke manifold system. When the wellbore pressure in the first region 85 is reduced to substantially zero, the balance of the drill string 105 is tripped out of the wellbore 10 in a similar manner as the procedure for tripping pipe in a dead well. During the trip into the wellbore 10 , the drill string 105 is rerun to a depth directly above the downhole deployment valve 50 , where a pipe-heavy condition exists. Subsequently, pressure is applied to the wellbore 10 to equalize the pressure in the first region and the second region below the valve 50 . When the pressures in the regions are substantially equal, hydraulic pressure from the surface fluid reservoir is applied through the control line to open the downhole deployment valve 50 , thereby opening the pathway into the region of the wellbore 10 below the valve 50 . Then the expandable filter member 185 is lowered into the wellbore 10 past the expandable portions 125 , 130 and the casing string 175 to a previously formed section of the wellbore 10 in a completion operation. The ability of performing a drilling operation and completion operation in an underbalanced environment will cause less damage to the reservoir formations.
[0046] Generally, the expandable filter member 185 comprises an overlapping mesh screen, sized for the particular sieve analysis solution and sandwiched between two slotted metal tubulars, an inner base pipe and an outer shroud that covers and protects the screen. As expandable filter member 185 is expanded, the pre-cut slots in both the base and shroud pipes expand and the screen material slides over itself to provide an uninterrupted screen surface on the wellbore 10 . The expandable filter member 185 maybe expanded by a rigid cone expander, a variable compliant expansion, or any other type expansion device.
[0047] In the past the greatest challenge of completing an underbalanced well using the expandable filter member 185 is deploying the porous unexpanded sand screen into a live, pressured wellbore 10 . Conventional snubbing options available to solid pipe will not work with the expandable filter member 185 . Killing the well to deploy the completion hardware likewise does not work because that defeats the objective of the underbalanced completion. The underbalanced drilling was possible, using snubbing equipment to trip under pressure to avoid pipe light conditions, but running sand screens was the challenge. However, the development of the valve 50 made the use of the expandable filter member 185 as an underbalanced completion system possible. As previously discussed, the valve 50 is used to drill the well underbalanced and to deploy the expandable filter member 185 . Typically, the expandable filter member 185 employs a modified Axial Compliant Expansion (ACE) tool for underbalanced compliant expansion. The modified Cardium liner hanger or an expandable liner hanger is used to hang the expandable filter member 185 before expansion begins. Membrane nitrogen or another gas is used to set the hanger and then to expand the screen using the pressure translation sub between the gas and the ACE tool.
[0048] FIGS. 8A-8D illustrate the different forms of the expandable portion. For instance, FIG. 8A illustrates an expandable portion 205 disposed at an end of a casing string 200 . As shown, the expandable portion 205 has an inner diameter (D 1 ) smaller than an inner diameter (D 0 ) of the casing string 200 . FIG. 8B illustrates an expandable portion 210 disposed in a shoe portion of the casing string 200 . As shown, the expandable portion 210 has an inner diameter (D 1 ) substantially equal to an inner diameter (D 0 ) of the casing string 200 , thereby resulting in a monobore configuration. FIG. 8C illustrates an expandable portion 220 disposed in a shoe portion of the casing string 215 which is mounted in a shoe portion of the casing string 200 . As shown, the expandable portion 220 has an inner diameter (D 2 ) substantially equal to an inner diameter (D 1 ) of the casing string 215 and an inner diameter (D 0 ) of the casing string 200 , thereby resulting in a sequential monobore configuration.
[0049] FIG. 8D illustrates an expandable portion 225 disposed below an end of the casing string 200 . As shown, the expandable portion 225 has an inner diameter (D 1 ) smaller than an inner diameter (D 0 ) of the casing string 200 . Similar to expandable portions 125 , 130 as shown in FIGS. 1-7 , one advantage of this embodiment is that only the trouble zone is being remediated rather than forcing the expandable casing to be installed from the trouble zone all the way back to the previous string of casing. Therefore, the expandable portion 225 requires a much shorter liner to be installed, creating a more cost effective expandable system to cure the trouble zone.
[0050] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | The present invention generally relates to methods and systems for mitigating trouble zones in a wellbore in a preferred pressure condition and completing the wellbore in the preferred pressure condition. In one aspect, a method of reinforcing a wellbore is provided. The method includes locating a valve member within the wellbore for opening and closing the wellbore. The method further includes establishing a preferred pressure condition within the wellbore and closing the valve member. The method also includes locating a tubular string having an expandable portion in the wellbore and opening the valve member. Additionally, the method includes moving the expandable portion through the opened valve member and expanding the expandable portion in the wellbore at a location below the valve member. In another aspect, a method of forming a wellbore is provided. In yet another aspect, a system for drilling a wellbore is provided. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cassette loading device of a tape recorder, and more particularly to a cassette loading device including a cassette holder and a conveyance mechanism for the cassette holder.
2. Prior Art
In the tape recorder market, specially so-called tape deck market, widespread are component types wherein a cassette is loading in a generally vertical direction to a front face panel of a cassette deck (in a direction generally parallel to the front face panel of the cassette deck), and is placed with its capstan side down so that letter on a label attached to the cassette on its face stand right for ease of reading.
Most of the conventional cassette decks employ a cassette holder as a means for cassette loading in which this cassette holder moves through a circular arc upon cassette loading.
FIG. 1 is a sectional view showing a conventional moving mechanism for a cassette holder to effect movement of the cassette deck through a circular arc, in which a cassette 1 is received in a cassette holder 2 which is rotatable about a shaft 3 between a cassette loaded position (shown by the solid line) and a cassette unloaded position (shown by two dots-chain line). With this arrangement, a capstan hole 4 of a cassette moves through a circular arc until it receives a capstan 5 when loaded, however, although the capstan hole 4 must measure 4.5 mm in diameter according to a standard, the diameter of the capstan 5 may take any value ranging from 2 mm to 3 mm and besides there is the trend to employ a capstan with a large diameter to hold extremely close tolerances upon finish of a product by grinding, holding surface vibration of the capstan at extremely low level, the capstan with a diameter not smaller than 2.5 mm being widespread in use at present. In such a cassette deck provided with a capstan having a diameter of 2.5 mm, for example, a radius R of a circular arc along which the capstan hole 4 moves must be 30 mm at the minimum for a practical use, and if the radius R is smaller than this value, the capstan hole 4 contacts with the capstan 5 or in a worse case the cassette 1 abuts the leading edge of the capstan 5, thus making it impossible to effect cassette loading operation. The present trend demands component type cassette decks having a shorter height, for example, one having a front face panel with 100 mm in height, in this case it is hardly possible to assure the minimum radius as mentioned above.
OBJECT OF THE PRESENT INVENTION
The task of the present invention is to provide a cassette loading device which is suitable for a tape recorder that is small and limited in its height, wherein a cassette holder for a cassette is allowed to move smoothly without any interference contact between a capstan and a capstan hole of the cassette and to take a position giving easy access to the cassette whereby the cassette can be easily inserted into or removed from the cassette holder and wherein those movable parts of the device are disposed within a height substantially the same as that of the cassette.
SUMMARY OF THE INVENTION
According to a cassette loading device of a tape recorder according to the present invention a pair of link mechanisms are disposed to the right and to the left of a cassette holder, respectively, and operatively connect the cassette holder to stationary portions of the tape recorder so as to allow movement of the cassette holder between a cassette loading position and a disengaged position giving easy access to the cassette. Each of the pair of link mechanisms includes a first link arm that has one end rotatably mounted on the corresponding stationary portion and an opposite end slidably mounted on the cassette holder. It also includes a second link arm that has one end rotatably mounted on the cassette holder and an opposite end slidably mounted on said the corresponding stationary portion. The first and second link arms of each link mechanism intersect each other and pivot on each other at their intersection. For synchronous movement of one of the link mechanisms with the other, the first link arms are interconnected for a unitary movement and/or the second link arms are interconnected for a unitary movement. Whereby as the intersecting angle of the first and second link arms varies, the cassette holder is allowed to move between said two positions.
The arrangement wherein at least one pair of link arms are interconnected for a unitary movement secures the smooth movement of the cassette holder toward the capstan regardless of the stress distribution applied to the cassette holder when subjected to the manipulation by an operator.
According to the preferred embodiment of the invention, the one and opposite ends of all of the link arms are equally spaced from the corresponding pivots that are disposed at the intersections, thus securing the straight movement of the cassette holder in parallel to the axis of the capstan. This dimensional relationship however is not essential to the present invention. Because the above described task can be accomplished also by moving the cassette holder along a circular arc that is sufficiently large enough to secure smooth insertion of the capstan into the capstan hole of the cassette, and in this case said dimensional relationship does not hold.
Preferably, in order to reduce the amount of retarding movement of the cassette holder from its cassette loading position and to minimize the space required, the cassette holder is provided with means whereby the cassette holder can pivot about the one ends of said second link arms right after the cassette holder has reached a position wherein the cassette has been removed from the capstan.
According to the preferred embodiment of the present invention, the opposite ends of the first link arms of the pair of link mechanisms that are disposed to the right and to the left of the cassette hodler, are received by a pair of slots with which the cassette holder is formed, each of these slots includes a straight slot portion and a circular arc slot portion. This arrangement allows the cassette holder to pivot about the one ends of said second link arms. During this pivotal movement of the cassette holder the opposite end of each of the first link arms is disposed in the corresponding circular arc slot portion.
The present invention is further described hereinafter in connection with the preferred embodiment illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a longitudinal section of a part of a tape recorder showing, in schematic, a cassette loading device according to the prior art;
FIG. 2 is a longitudinal section of a part of a tape recorder showing, in schematic, the right side of a cassette loading device according to the present invention, the device being in the first disengaged position;
FIG. 3 is the same view as FIG. 2 but the cassette loading device is in the second disengaged position;
FIG. 4 is the same view as FIG. 2 but the cassette loading device is in the cassette loading position;
FIG. 5 is a plan view of a guide plate of the cassette loading device shown in FIGS. 2 to 4;
FIG. 6 is a plan view of a second link arm of the cassette loading device shown in FIGS. 2 to 4;
FIG. 7 is a diagram showing the dimensional relationship between cooperating first and second link arms of the cassette loading device; and
FIG. 8 is a longitudinal section of a part of the tape recorder showing, in schematic, the left side of the cassette loading device shown in FIGS. 2 to 4 but the device is in the second disengaged position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of a cassette loading device according to the present invention is hereinafter described in connection with FIGS. 2 through 8 of the accompanying drawings, wherein like reference numerals are used to designate like parts throughout various views.
Referring to FIGS. 3 and 8, one of a pair of mechanisms of the cassette loading device disposed to the right of the cassette holder is shown in FIG. 3, while the other mechanism of the pair disposed to the left of the cassette holder is shown in FIG. 8.
Referring to FIGS. 3, 2 and 4, FIG. 3 shows a second disengaged position that gives an easy access to the cassette, FIG. 2 shows a first disengaged position, and FIG. 4 shows a cassette loading position. It will be understood as the description proceeds that when loading the cassette the cassette holder is moved from FIG. 3 position to the FIG. 4 position via FIG. 2 position, while when removing the cassette the cassette holder is moved from FIG. 4 position to the FIG. 3 position via FIG. 2 position.
Referring to FIGS. 2 through 4 wherein the reference numeral 1 designates a cassette that may be loaded by means of a cassette holder 7, this cassette holder 7 is one piece product of a synthetic resin and includes integrally formed side plate portions 8 and back plate portion 9. Each of the side plate portions 8 of the cassette holder 7 has a shaft 10 embedded to a lower portion thereof, and formed on an upper portion of each side plate portion 8 is a slot 11 consisting of a straight portion 11a extending in substantially parallel to the back plate 9 and a circular arc portion 11b extending along a circular arc with said shaft 10 as its center.
The reference numeral 12 designates a guide plate for the cassette holder which, as shown in FIG. 5, is composed of first link arms 13 and 13' and a substantially flat interconnecting member 14, wherein right and left link arms 13 and 13' are formed with holes 15 and 15', respectively, at respective one end portions thereof, the link arms 13 and 13' have inwardly extending pin 16 and 16' embedded to the respective opposite end portions thereof, and the link arm (right) 13 and link arm (left) 13' have a shaft 17 and a shorter shaft 18, respectively, embedded to respective center portions thereof.
The reference numeral 19 designates a second link arm, which, as shown in FIG. 6 is provided with a hole 20 at one end portion thereof, a pin 21 at the opposite end portion thereof, and a hole 22 at center portion thereof.
The reference numeral 23 designates a mechanism carrying base mounted substantially upright and the mechanism base 23 is provided with two rotatable reel receiving shafts 24 projecting therefrom and with a rotatable capstan 5 received by a capstan bearing 25 and projecting therefrom.
The reference numeral 26 designates a link carrying plate (stationary member) which serves also as an attaching member for the above-mentioned mechanism carrying base 23 and which has a bent lower edge portion 27 screwed to a cassette deck base plate 28. Embedded at a lower portion of this link carrying plate 26 is a shaft 29 disposed in the hole 15 and a slot 30 is formed within an area above and in line with the shaft 29 for receiving the pin 21 of the second link arm 19 to permit same to slide.
Referring to FIGS. 2 to 4, only right-hand side of the device according to the present invention is shown wherein one of the pair of side plate portions 8, one of the pair of first link arms 13, one of the pair of second link arms 19 and one of the pair of link carrying plates 26 only are shown, however, the left-hand side of the device is similarly constructed as shown in FIG. 8.
The interconnecting member 14 is formed, by piercing, with holes 14a and 14b to permit the reel receiving shafts 24 to pass therethrough, respectively, and with a cutout 14c to permit the capstan bearing 25 to pass therethrough, as shown in FIG. 5 because the guide plate 12 is rotatable about the shaft 29 and the interconnecting member 14 which is disposed between the cassette 1 and the mechanism base 23 assumes a position wherein it is disposed in parallel with and near the mechanism base 23 when the device is in the position shown in FIG. 4 wherein the cassette is loaded. Besides the guide plate 12 has a function to conceal the drive and the other things of the mechanism when the cassette holder is in the disengaged position shown in FIG. 2 or FIG. 3.
The first link arm 13 is pivotable with its one end rotatably mounted on the shaft 29 formed on the link carrying plate 26, and has the inwardly embedded pin 16 to pass through the slot 11, while, the second link arm 19 disposed outwardly of the corresponding first link arm 13 has the hole 20 formed at one end portion thereof to receive the shaft 10 on the side plate portion 8 of the cassette holder and has the pin 21 on the opposite end portion to pass through the hole 30, the second link arm having the hole 22 to receive the shaft 17 on the first link arm 13 so that the second link arm lies across or intersect the first link arm. Therefore, the first link arm 13 and the second link arm 19 cooperate to operate as a linkage, and, upon loading or unloading a cassette, the cassette holder is allowed to advance towards or retard from the link carrying plate 26 as the intersecting angle between the first and second link arms 13 and 19 varies. With this arrangement the accurate parallel movement can be assured if the following dimensional relationship holds, that is, a=b=c=d, where, in FIG. 7, a and b refer to the first link arm 13 and represent a distance between the shaft 17 and the hole 15 and a distance between this shaft and the pin 16, respectively, and c and d refer to the second link arm 19 and represent a distance between the hole 20 and the hole 22 and a distance between the hole 22 and the pin 21, respectively, and this relationship is satisfied in this embodiment.
The above mentioned dimensional relationship is necessary when it is required to effect the parallel movement along a straight line, however, this limitation can be eliminated if the cassette holder 7 is moved, instead of the parallel movement, along a circular arc with an extremely large radius, and in this case since the center of the circular arc is not real but imaginary, the height of the cassette deck can be designed small as much as that of the preferred embodiment, and since the radius can be made large sufficiently as desired, smooth action upon inserting the capstan into the cassette is assured without any hindrance.
The reference numeral 33 indicates a torsion spring which winds the shaft 10 of the cassette holder 7 with one end fixed to the side wall portion 8 and with the opposite end abutting against the second link arm 19 so that with the same torsion spring the cassette holder 7 is biased to effect the parallel movement in a direction of an arrow B and the circular arc movement in a direction of an arrow C.
The reference numeral 34 designates a lock arm which is rotatably supported by a shaft 35 embedded to the link carrying plate 26 and is biased by a spring 36 clockwise, and with this arrangement the lock arm can lock the pin 17 on the first link arm 13, the clockwise rotation of the lock arm subject to the spring being limited by a stopper pin 37.
The reference numeral 38 designates a front face panel of the cassette deck which is formed with an opening 39 allowing the cassette holder 7 to pass therethrough upon its advancing or retarding movement and which is provided at its corner portion an inject button 40, wherein pressing this inject button 40 against a spring 32 causes, via an inject rod 31, to rotate the above-mentioned lock arm 34 counterclockwise, thus unlocking or releasing the above-mentioned pin 17.
The reference numeral 41 designates a cassette door for closing the opening 39 of the front face panel, the cassette door being fixed by screws to the front face of the cassette holder 7.
The construction of the cassette loading device according to the present invention has been described hereinabove, now its operation is described in the following.
In the second disengaged position shown in FIG. 3, the cassette holder 7 is in a position angularly displaced, about the shaft 10, counterclockwise under the action of the spring 33, and the guide plate 12 is angularly displaced, about the shaft 29, counterclockwise too. In this state, the pin 16 at the upper portion of the first link arm 13 is disposed in the circular arc portion 11b and abuts its terminal end to define the angular position of the cassette holder 7.
In this position, the cassette door 41 is spaced from the front face panel 38 by a sufficient amount so that the cassette 1 can be picked up from or inserted into the cassette holder 7 easily.
In the casette door 41 receiving the cassette 1 is pressed in a direction indicated by an arrow A, the cassette holder 7 pivots clockwise about the shaft 10 against the spring 33. It is to be noted that since the distance between the pin 16 and pin 10 is unchanged as far as the pin 16 of the first link arm 13 is disposed in the circular arc portion 11b of the slot 11, the guide plate 12 and the second link arm 19 remain in their respective illustrated positions of FIG. 3 and the cassette holder 7 alone is allowed to pivot until the pin 16 reaches the straight portion 11a of the slot 11, that is, until the first disengaged position shown in FIG. 2 is assumed.
In the position shown in FIG. 2, the cassette holder 7 and cassette 1 are disposed in parallel relationship to the mechanism carrying base 23 in a spaced relationship and the capstan hole 4 is aligned with the capstan 5 just before receiving same. In this position the pin 16 of the first link arm 13 is disposed in the straight portion 11a of the slot 11 of the cassette holder 7 so that if the cassette door 41 is pressed further in the direction indicated by the arrow A, the pin 16 moves upwards along the straight portion 11a and the pin 21 of the second link arm 19 along the slot 30 of the link carrying plate 26, allowing the first link arm 13 and the second link arm 19 to vary their intersecting angle thus permitting the parallel movement of the cassette holder 7 in the direction indicated by the arrow A. Therefore, allowing the capstan 5 to pass through the capstan hole 4, the cassette 1 is brought into a position when the device is in the cassette loading position shown in FIG. 4. The cassette holder 7 is kept in the illustrated position in FIG. 4 against the biasing force of the spring 33 since the hook portion 34a of the lock arm 34 engages the shaft 17 embedded to the first link arm 13 to lock same.
The cassette loading being carried out by steps in the above described order, the cassette unloading is carried out by the same steps in the reverse order. Explaining this in the following, when the device is in the cassette loading position shown in FIG. 4, pressing the inject button 40 causes the lock arm 34 to rotate counterclockwise, thus releasing the lock on the above mentioned shaft 17 on the intersection of the link arms. This allows the second link arm 19 to rotate clockwise and the first link arm 13 to rotate counterclockwise owing to the action of the spring 33. As the angular movement of the cassette holder 7 is prevented because the pin 16 of the first link arm 13 is disposed in the straight portion 11a of the slot 11, the cassette holder 7 is allowed to effect the parallel movement, towards the position shown in FIG. 3, before moved backwards to take a position wherein the capstan hole 4 is spaced from the capstan 5 (the first disengaged position of the cassette holder).
At the position shown in FIG. 2, the parallel movement of the cassette holder 7 is followed by the counterclockwise rotary movement thereof also owing to the action of the spring 33 till plunging into the position shown in FIG. 3 (the second disengaged position of the cassette holder) because the above mentioned pin 16 has been put into the circular arc portion 11b of the slot 11.
It is to be understood that the position of FIG. 2 represents the transitional state during cassette loading or unloading process and so does not indicate that the cassette holder 7 stops temporarily to stay in this position.
It can be recognized from the description of the preferred embodiment that a special arrangement has been employed to secure smooth and continuous movement of the cassette holder so that even if an operator presses any desired portion, such as, the right edge or the left edge of the cassette door, of the cassette door, the pair of linkage mechanisms move synchronously.
In the preferred embodiment, there is employed the guide plate 12 as shown in FIG. 5 wherein the right and left link arms 13 and 13' are integrated or interconnected by the interconnecting member 14 that has a rigidity sufficiently great enough to withstand a twisting force. This secures a unitary pivotal motion of the link arms 13, 13' about the shaft 29 because the guide plate 12 is pivotable about this shaft 29. This unitary motion of the link arms 13, 13' secures synchronous and smooth motion of the link mechanisms in such a manner that the intersecting angle of the cooperating link arms of one of the link mechanisms varies at the same timing and by the same degree with the intersecting angle of the cooperating link arms of the other link mechanism.
Although, in the preferred embodiment, the cassette holder is allowed to pivot after its parallel movement to the axis of the capstan, such motion may be replaced by the parallel movement only although in this case the amount of the parallel movement necessarily increases as compared to the preferred embodiment.
It can also be recognized that the movable parts or members constituting the cassette loading device, such as, cassette holder 7, guide plate 12, link arms 19, are disposed to occupy a space that has substantially the same height as the cassette, thus making a significant contribution to the reduction in height of the cassette loading device.
It can also be recognized in connection with the preferred embodiment that the possibility that the capstan hole of the cassette may be brought into interference contact with the capstan is precluded because the cassette is moved in parallel to the axis of the capstan when loading the cassette, thus securing smooth engagement of the cassette with the capstan even if the diameter of the capstan is increased.
It can also be recognized that the cassette loading device according to the present invention secures accurate loading of the cassette regardless of the location on the cassette door of the application of force by manipulation of an operator because of synchronous movement of the pair of link mechanisms.
It can also be recognized in connection with the preferred embodiment that a manipulating space enough for inserting the cassette into the cassette holder or removing same from the latter is provided because of pivotal movement of the cassette holder before assuming the second disengaged position shown in FIG. 3.
It can also be recognized that the cassette loading device according to the present invention can be applied to a thinner component-type cassette deck that has a considerably reduced height because the height occupied by the cassette loading device of the present invention is substantially the same height as that of the cassette. | A cassette loading device of a tape recorder comprises a cassette holder and a pair of link mechanisms which are disposed to the right and to the left of the cassette holder and which operatively connect the cassette holder to the stationary portions of the tape recorder so as to allow the cassette holder to smoothly move between a cassette loading position and a disengaged position giving easy access to the cassette. Each of the pair of link mechanisms includes a first link arm that has one end rotatably mounted on the corresponding stationary portion and an opposite end slidably mounted on the cassette holder for travel within communicating straight and arcuate slot portions; a second link arm has one end rotatably mounted on the cassette holder and an opposite end slidably mounted on the corresponding stationary portion. The first and second link arms of each link mechanism intersect and pivot each other at their intersection. For synchronous movement of one of the link mechanisms with the other, the first link arms and/or second link arms are interconnected for a unitary movement. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to bedding, namely, mattresses and box springs. More particularly, this invention relates to stress-relieving treatment of coil springs for placement in pocketing material for subsequent use in mattresses or box springs.
2. Description of Related Art
It is known to form wire into individual coil springs and to combine such coil springs into a single innerspring unit which may be used as a mattress or as a box spring.
It is also known to provide individually "pocketed" coils and to assemble such pocketed coils into innerspring constructions for later upholstery into mattresses or box springs. An example of a method and apparatus for assembling such pocketed coil springs is shown in U.S. Pat. No. 4,439,977 to Stumpf, which is incorporated herein by reference. Methods and apparatus for combining groups of pocketed coils into a unitary string or array of coils for installation as innerspring units within a mattress assembly as illustrated in U.S. Pats. Nos. 4,578,834, and 4,986,518 which also are incorporated by herein reference.
Although the above systems provide several advantages over prior constructions, a need for improvement still exists. For example, when coils are compressed for insertion into pockets as shown in U.S. Pat. No. 4,439,977, the coils may tend to "set" resulting in a disadvantageous permanent height or load loss. Disadvantages also exist in that the wire tends to undergo certain stresses during formation which may cause residual faults in the coil springs.
Therefore, a need has been recognized in the industry to provide springs which do not exhibit stress induced problems including disadvantageous "set" conditions.
General heat treatment of coil springs is known. For example, it is known to provide "open-coil" innerspring constructions, and then to place such open coil innerspring constructions into an oven for stress relief. However, in the instance of innerspring constructions of pocketed coils, such constructions do not lend themselves to oven-heating since, for example, the pocket fabric or the glue holding the pocketed coil springs together will degrade if subjected to high temperatures as will be encountered with oven heating.
Therefore, a need has been recognized to provide a method and apparatus for providing improved pocketed coils and innerspring constructions made therefrom and to the products produced thereby.
SUMMARY OF INVENTION
The present invention provides improved pocketed coils and innerspring constructions made therefrom, in which pocketed spring wire metal coil springs are heat treated or otherwise conditioned prior to their insertion into pocketing fabric in a manner such that inherent residual stresses in the spring wire are reduced to enable the durability and resilience of the coil springs to be maintained over an extended period of time. Particularly, the present invention relates to methods and apparatus for heat treating coil springs formed from wire, and subsequent insertion of such coil springs into pocketing fabric, as well as to the mattress products produced therefrom as well as the coil springs produced thereby.
With respect to requirements and materials transformation for reducing or fully eliminating undesirable residual stresses in the wire of a compression coil spring, it should be noted that such residual stresses in the wire of a compression coil spring are generally of two types, i.e., wire drawing residual stresses and coil formation residual stresses. Both types of stresses result from cold working of the metal in the spring wire.
With respect to wire drawing residual stresses, when the carbon steel wire is manufactured for a pocketed coil spring application it is cold drawn, for example, from hot rolled high carbon 1070 steel rod in diameters of 7/32"(0.21875") or 1/4"(0.25"). These rods normally are reduced in diameter reduction dies until it reaches a wire diameter range of 0.068" to 0.094". The substantial cross-sectional area reduction resulting from this cold working strain (deformation) in the wire results in the build-up and retention of distinct types of residual stress patterns, including longitudinal stresses (parallel to the axis of the wire, tensile at the wire surface and compressive at the axis of the wire), radial stresses (essentially perpendicular to the axis of the wire and compressive at the axis), and circumferential stresses (which follow the same pattern as the longitudinal stresses).
With respect to coil formation residual stresses, when the wire is formed into a compression coil spring certain additional residual stresses are added to and are believed to alter the residual stresses already present in the wire from the wire drawing operation. These additional coil formation stresses resulting from this additional cold working result in additional differential plastic strain (deformation) in the wire and in the resultant build-up and retention of other types of residual stress patterns in the wire, which include compressive residual stresses (in the wire material located to the interior of the mean coil diameter), tensile stresses (in the wire material located to the exterior of the mean coil diameter), and torsional stresses, as the wire contained in the active convolutions of the spring contains some levels of torsional residual stresses, resulting from twisting of the wire as the helical convolutions of the coil compression spring wire were formed.
It has been known that in the combination of the aforementioned wire drawing and coil formation residual stresses present problems in regard to compression coil spring performance, load carry, free height retention, set resistance, and fatigue resistance. Therefore, relief of these undesirable stresses is necessary.
In order to achieve stress relief of compression coil springs in pocketed coil products, mechanical plastic deformation may be selectively applied to provide a balance in stresses. However, preferably, heating is selectively applied to achieve a balance in stresses. These processes may be followed by cooling to permit safe insertion of the compression coil spring into the fabric pocket.
Residual stress reduction up to and including full relief of undesirable stress relief can be accomplished by a number of methods, including but not limited to selective mechanical cold working or the wire in the spring (such as shot peening), ultrasound treatment, laser heating, heating in a resistance furnace, induction heating, electrical resistance heating, forced hot air heating, or radiant heating. However, regardless of which method is used, those methods involving the application of heat are preferred over the other alternatives. Also, regardless of which method is used, a certain and specified heating temperature and time must be applied to the spring undergoing stress relief and, thereafter cooling must take place down below a specified temperature in order to permit the insertion of the coil spring into a fabric pocket without detrimental effects to the pocket and pocket fabric.
One preferred time/temperature process for relieving stress on coil springs is now discussed, and it should be noted that time is stated in intervals, and the described case, a single time interval is equal to 700 to 800 milliseconds. In the preferred process, the temperature of the spring is elevated to the range of between 420 degrees F. and 1333 degrees F., but preferably approximately in the narrower range of 500-700 degrees F. all within a single time interval is not enough to complete heat penetration and, thus, complete undesirable stress relief. Then a sufficient number of additional time intervals are required. In this case the means of achieving process function is to utilize 2, 3, 4, 5. . . N time intervals. Provisions for each time interval to take place without slowing the production rate of the machine will merely require additional conditioning chambers and the appropriate amount of in-line space to accommodate these chambers.
Potential methods to achieve the cooling function, include but are not limited to recirculating oil bath cooling, recirculating water cooling, combination air/water mist cooling, compressed air vortex cooling, forced refrigerated air cooling, and forced ambient temperature air cooling. Forced air cooling is the preferred method for cooling. However, regardless of which cooling method is used, a certain and specified cooling temperature and time must be applied to the spring which has undergone stress relief and cooling of the spring must take place below a specified temperature in order to permit the insertion of the coil spring into a fabric pocket without detrimental effects to the pocket and pocket fabric.
One preferred time/temperature for the cooling process would be to reduce the spring to a temperature in the range of 0-730 degrees F. in a single time interval. If one time interval is not enough to achieve cooling to the desired temperature, then a sufficient number of additional time intervals may be required. In this case, the means of achieving this process function is to utilize 2, 3, 4, 5. . . N time intervals. Provisions for each time interval to take place without slowing the production rate of the machine will merely require additional conditioning chambers and the appropriate amount of in-line space to accommodate these chambers.
As may be understood, it is necessary to follow the above-referenced processes with insertion of the stress relieved and cooled spring into a fabric pocket.
Therefore, it is an object of the present invention to provide an improved pocketed coil construction for use in an innerspring structures.
It is a further object of the present invention to provide an improved innerspring construction for use in a mattress or box spring.
It is a further object of the present invention to provide an improved method and apparatus for providing pocketed coil springs, in which the coil springs are conditioned to relieve stress therein, prior to being inserted into pocketing fabric.
It is a further object of the present invention to provide an improved method and apparatus for manufacturing pocketed coil springs, which is cost-efficient in operation, construction, and maintenance.
These and other objects, features, and advantages of the present invention will become apparent upon reading the following detailed description of the preferred embodiments of the invention when taken in conjunction with the drawing and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1C are overall views of an apparatus embodying the present invention for use in the processes of the present invention, FIG. 1A is a top plan view of the inventive apparatus. FIG. 1B is a front elevation view of the apparatus of FIG. 1A, and FIG. 1C is a side elevation view of the apparatus.
FIGS. 2A-2C are views of the apparatus of the present invention, FIGS. 1A-1C, further including an induction heating station used for heating a coil spring in accordance with this invention.
FIGS. 3A-3C are views of the apparatus of the present invention such Figs. 1A-1C, further including a radiant heating station used for heating a coil spring in accordance with this invention.
FIG. 4 is a cross-sectional view of a radiant heating assembly for use in the heating station illustrated in FIG. 3.
FIGS. 5A-5C are views of the apparatus of the present invention as illustrated in FIGS. 1A-1C, further including an electrical resistance heating station used for heating a coil spring in accordance with this invention.
FIGS. 6A-6C are views of the apparatus of this invention such as illustrated in FIGS. 1A-1C, further including a forced air heating station used for heating a coil spring in accordance with this invention.
FIG. 7 is an isolated view of a pocketed coil indexing and welding apparatus employed in the present invention.
FIG. 8 is a pictorial view illustrating the operation of the forming tube utilized in accordance with the method of the present invention.
FIG. 9 is a side elevation view illustrating the operation of guidance rods in accordance with the present invention.
FIG. 1 () is a schematic view illustrating the coil springs of the present invention inserted into a fabric defined pocket forming a part of an elongate string of such pocketed coil springs for use in producing an innerspring construction.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the Figures, in which like numerals correspond to like items throughout the several views, Figs. 1A-1C illustrate apparatus 10 according to the present invention, which includes a pocket material feed station 22 which feeds pocket material 13 from a roll 24 of synthetic or natural fabric along a path 25, around dancer rollers 26, to a coil conditioning carousel 40 (cover not shown in FIGS. 1A-1C) which is mounted for rotating motion and includes cavities 39 therein. Carousel 4()is positioned to accept unconditioned coil springs 12 at cavity insertion position 41 from a coiler head 50. These coil springs 12 are then conditioned, as discussed later in this application, and the conditioned coil springs 12 are deposited out of carousel 40 at cavity exit position 42 into a pocket forming station 30. A pocketed string 55 of coil springs 12 is then formed from these deposited, conditioned springs 12. A computer 11 is employed to control the operation of this process.
It will be understood that the coil conditioning carousel 40 periodically rotates in an intermittent fashion, with the carousel 40 periodically indexing at each machine cycle. For the carousel 40 shown in FIGS. 1A-1C, eight cavities 39 are present, so the carousel indexes eight times or "cycles" per each full carousel revolution. For the carousels 40 shown in FIGS. 2A-2C 3A-3C, 5A-5C and 6A-6C, twelve cavities are present, so these carousels index twelve times or "cycles" per each full carousel revolution. The cavities 39 of the conditioning carousel 4() may be lined with heat insulating material, if desired.
Referring now to FIGS. 2A-2C, an apparatus 60 for conditioning coil springs is illustrated which includes devices for induction heat conditioning the coil springs 12. As in FIG. 1, unconditioned coil springs 12 are provided from a coiler head 50. In the path 25 from the coiler head 50 to the coil conditioning carousel 40 as illustrated in FIGS. 2A-2C, each coil spring 12 is stopped for one cycle in at least one induction heating station or chamber 61. Each heating station 61 has an induction heating coil 43 therein. The induction coil 43 is supplied with high frequency current from a separate power supply 62. The high frequency current in the heating coil 43 produces a fluctuating magnetic field which induces current flow in each coil spring 12 as it is transported through station 61. The induced current provides rapid heating of each coil spring 12 to the desired temperature range of from about 500 degrees F. to about 700 degrees F., preferably about 600 degrees F.
After being heated by induction, the coil springs 12 are sequentially placed into the conditioning carousel 40, which in FIGS. 2A-2C is shown to include a cover. Cooling ducting 63 is provided to channel air to and from a cooling station 64. As discussed later in detail, the ducting 63 enables cooling air to be directed across one or more cavities 39 in the carousel 40, so that as a particular coil spring 12 is indexed along with the carousel 40, the coil spring 12 is cooled for at least one cycle. If more than one cavity is cooled as shown in FIGS. 2A-2C, the direction of the cooling air alternates for each cavity 39 due to the looped or turned-back configuration of the ducting 63 best illustrated in FIGS. 2C, 3C and 5C.
In each induction heating station 61, the coil springs 12 are passed axially along a path which essentially passes through the center of an induction coil 43. The induction coil 43 is configured to allow coil springs 12 to pass through its center without interference. In a preferred configuration of the induction coil 43 as best illustrated in FIG. 2A, the induction coil 43 has a throat dimension of about 5" inside diameter, is about 8" long, and has between 2 and 6 convolutions therein.
One method of positioning the coil springs 12 within the induction heating station 61 is by the use of nonconductive guide rods 71 (see FIGS. 4 and 9) which hold the coil springs 12 in place during the heating process. The guide rods 71 provide radial guidance of the coil springs as they travel along a longitudinal axis through the induction coil 43 and station 61. As in the case or radiant heating which will be discussed hereinafter, the coil springs 12 may be transferred along their path through station 61 via a blast of air provided by blower element 91.
Referring now to FIGS. 3A--3C, an apparatus 70 for conditioning coil springs 12 is illustrated which employs radiant heat to condition the coil springs 12.
In the path 25 from the coiler head 50 to the coil conditioning carousel 40, coil springs 12 enter at least one radiant heating chamber 74 including electrically powered ceramic radiant heaters 72 (see also FIG. 4). The heaters 72 convert electrical energy into radiant energy at a frequency which yields efficient heat transfer to the coil springs 12. One or more radiant chambers 74 may be used in line to achieve the desired production rate with the coil 12 being heated to between about 500 degrees F. and about 700 degrees F., preferably about 600 degrees F.
As illustrated in FIG. 4, the coil springs 12 are conditioned by radiant heat treatment utilizing radiant heaters 72. As may be seen, three heaters 72 each include elongate radiant, ceramic, heating elements 73, which all face axis A, which is preferably the longitudinal axis of a spring coil 12 being heated. The length of the element 73 is preferably approximately equivalent to the longest coil contemplated for processing. Suitable heaters 72 for use herein are sold by Sylvania, as Model No. 066612.
In a manner similar to that described above in regard to induction heating of the coil springs 12, insulative guide rods 71 as shown in FIGS. 4 and 9 may be used in moving the coil springs 12 through the heating chamber 74. Also, the previously discussed air blast transfer provided by blower member 91 may be employed, if desired.
After the coil springs 12 are heated, they are directed into the conditioning carousel 40 for soaking, cooling, and subsequent placement into pocketing fabric 13.
In FIGS. 5A-5C, an apparatus 80 for conditioning coil springs 12 is illustrated which uses copper or other contact plates 83 between which the coil springs 12 may be placed for heat conditioning the coil springs 12.
In the path from the coiler head 50 to the coil conditioning carousel 40, each coil spring 12 is stopped within an electrical resistance heating chamber 81, and copper contact plates 83 are pressed into contact with opposite ends of each coil spring 12. The contact plates 83 connect the coil springs 12 into an output circuit of a low voltage, high current power transformer 82. With contact fully established the power supply is energized for a brief period, typically 200 milliseconds or less. The high current will then flow directly through each coil spring 12 and will heat the coil spring 12 to between about 500 degrees F and about 700 degrees F, preferably about 600 degrees F.
As previously discussed, the conditioned coil springs 12 are then sent to the carousel 40 and later placed into pocketing material 13.
Referring now to FIGS. 6A-6C, an apparatus 90 for conditioning coil springs is also illustrated which includes the use of heated air to heat condition the coil springs 12.
In one embodiment of the present invention, after coil springs 12 leave the coiler head 50 ambient air from a blower 86 is heated to at least about 700 degrees F. by a heater 85 such as an electrical resistance heater, in a closed air stream. Then, the coil springs 12 are transported for insertion into coil conditioning carousel 40. In the illustrated construction, heat ducting 84 guides heated air from air heater 85 through at least one cavity 39 of the carousel 40 to heat coil springs therein to between about 500 degrees F. and about 700 degrees F., preferably about 600 degrees F.
In a preferred embodiment of this invention, "soaking"of the coil springs is accomplished while just-heated coil springs are in the carousel but are not being cooled. The term soaking is used to describe the transfer of heat from the outer skin of the wire to the core of a wire, that is, the allowance of temperature gradients to be reduced across the cross section of wire strands. Typically, in preferred embodiments, this is done by allowing the coil springs to rest within a particular cavity without heat being transferred to or from the cavity by outside means. For example, in the configuration of FIGS. 2A-2C, the coil springs 12 may soak for up to 6 cycles before being cooled.
In accordance with the present invention, it is preferred that once a coil spring 12 has been heated to an appropriate temperature which may range from about 400 degrees F. to about 1300 degrees F., but normally will be in a range of between about 500 and about 700 degrees F. employing the preferred techniques as illustrated in FIGS. 2-6 herein and as described in accordance with this detailed description of the invention, the coil spring 12 must be cooled to a temperature which will allow the coil spring 12 to be inserted in pocketing material 13 without causing damage to the fabric structure. Thus, in preferred embodiments of this invention employing natural fabrics as the pocketing material 13, the coil springs 12 should be cooled to a temperature not exceeding approximately 150 degrees F. before they are inserted into the pocketing material 13. For certain synthetic fabrics, the spring coil cooling temperatures may be significantly higher than for natural fabrics and may range up to a temperature of about 700 degrees F.
The cooling of the coil springs 12 may be accomplished using a variety of cooling techniques including forced air circulation, recirculating oil baths, recirculating water, combination air/water mists, compressed air vortex cooling, forced refrigerated air cooling and the like.
For example, cooling of the coil springs 12 may suitably be achieved by employing ambient air which is pressurized, for example, to 10 inches water column pressure and then ducted to a series of chambers in the coil conditioning carousel 40. With high velocity, high volume air directed across the coil spring wires and due to the relatively low (typically 30 gram) mass of the coil springs 12, cooling can be achieved in four or less chambers. In the configuration shown in FIG. 2A-2C, the air is directed through four separate cavities 39, with air flow being redirected to in an opposite direction each successive cavity.
Reference is now made to FIGS. 7 and 8 for an understanding of the apparatus and process for inserting coil springs 12 into pockets defined by pocketing material 13. Generally, it should be understood that the process includes the steps of forming an elongate tube of fabric 112)7, inserting a coil spring 12 into the tube, and forming a pocket 123 around the coil spring 12, for example, by bonding as by ultrasonically welding, two seams 108 transverse to the longitudinal axis of the tube 107, one seam 108 on each side of the coil spring 12 to capture the coil spring 12 within the fabric pocket 123. By using two pairs of jaws 102, 103 and 104, 112)5, respectively, which serve to hold the coil springs 12 and fabric 13 in place for the welding process, and which serve to index the completed pocketed coil springs 124 out of the way to allow for a repeat of the process.
As shown in FIGS. 7 and 8, the fabric 13 is passed over an idler roller 27 (see also FIG. 1B), in substantially flat form. The fabric is then "gathered" around the outside of a forming tube 11 (suspended by two rods 111, and including a leading mouth loop or forming ring 1! 2)9. The fabric 13 is drawn through the tube 110 so as to create a fabric tube 107 at the exit or downstream mouth of the forming tube 110, with the free edges of the fabric overlapping in a flat seam at 108.
The loop or forming ring 109 is attached at the leading mouth of the forming tube, and provides smooth guidance of the fabric 13. Fabric 13 may be "gathered" to merge by guiding rollers (not shown), which may be of the spiked or deformable type as known in the art.
As previously discussed, the coil springs 12 are cooled in the conditioning carousel 40. At the end of each indexed rotation of the carousel 40, a conditioned coil spring 12 will be discharged as by falling under the influence of gravity, out of an exit hole 120 in the cover of the carousel 40. The metal coil spring 12 lands on a magnet 121, which holds it in place while a pair of synchronized compression side flaps 114 (only one shown in FIG. 8) come together to compress and center the coil while still atop the magnet 121. A reciprocating pushing element 112 driven by means known in the art pushes the coil off the magnet in a rolling fashion and into the throat of the fabric tube 107, itself in the throat of the forming tube 110.
The coil springs 12 are retained within the forming tubes 110 by friction between the ends of the coil springs 12 and the fabric 13. The fabric 13 is in frictional contact with the inwardly-directed vertical side surfaces 113 of the forming tube 110. A particular coil spring 12 is pushed into place by the pushing element 112 just after a previous coil spring 12 has been drawn or indexed downstream by a tensile force on the fabric tube 107. As will be discussed later, this tensile force is provided by a gripping action of jaws 102-105 positioned downstream of the forming tube.
There are two sets of jaws 102-105, a front set, and a rear set, which operate in synchronism. The front jaw set includes a front upper jaw 102 and a front lower jaw 103, which operate in synchronism. The rear jaw set includes rear upper jaw 104 and rear lower jaw 105, which operate in synchronism.
The front set of jaws 102, 103, combine to grip a particular coil spring 12, and the rear set of jaws 104, 105 combine to grip another coil spring 12 a number of coil springs downstream (three in the illustrated embodiment).
The jaws are similar, in that each is comprised of right and left side wall members mounted to opposing sides of a central "half-tube". When two jaws of a set come together as shown in FIG. 7, the two "half-tubes" come together to in effect "clamshell" a coil within fabric. This has an advantageous alignment effect. The rear jaw set provides additional tensile force during indexing.
After a pair of coil springs 12 are gripped with the jaws in the positions shown in FIG. 7, the ultrasonic welding stack 100 including horn 99 is moved upwardly such that the overlapped tube of pocketing fabric 13 is "pinched" between horn 99 and an anvil bar 101 rigidly attached to the front lip of front upper jaw 102. The anvil bar 101 is "notched" to provide an intermittent transverse weld. The horn 99 is then ultrasonically energized such that the horn 99 and the anvil bar 101 combine to form an intermittent transverse thermal weld, which, when repeated, forms pockets 123 into which coil springs 12 are inserted to form the pocketed coil spring products 124 with coil springs 12 in pockets 123 formed from pocket material 13 as illustrated in FIG. 10.
After the welding process, the stack 100 is then withdrawn to its retracted position as shown in FIG. 7. A reciprocating carriage (not shown) holding the front and rear jaws 102, 103, 104, and 105 is then indexed by a suitable means such as a pneumatic cylinder to pull the entire coil string 55 just over one coil diameter in distance. In order that the process may be repeated, the jaws 102-105 are then returned to grip the next available coil spring.
Under one preferred embodiment, the steps of a) gripping, b) welding, c) indexing, d) release, and e) return occur in that order and in a single overall matching cycle.
Although stationary welding is described above, it should be understood that welding could be performed in a reciprocating manner "on the fly" by mounting the horn 99 onto the reciprocating carriage holding the jaws 102-105, which are pivotally mounted to the carriage at pivot points such as "P" in FIG. 7.
While this invention has been described in specific detail with reference to the disclosed embodiments, it will be understood that many variations and modifications may be effected within the spirit and scope of the invention as described in the appended claims. | A method and apparatus for manufacturing mattresses, including the steps of forming a coil spring from wire, conditioning said coil spring to reduce stresses formed therein, placing said coil spring within pockets to create elongate strings of pocketed coil springs, attaching said elongate strings to create innerspring constructions. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority under 35 U.S.C. §119(a) of Korean Patent Application No. 10-2007-0130398 filed on Dec. 13, 2007, the entire contents of which are incorporated herein by reference.
BACKGROUND
(a) Technical Field
The present invention relates to a polyurethane foam with improved water resistance for use in an automobile steering wheel.
(b) Background Art
Polyurethane resin is formed by a chemical reaction between a liquid-phase polyol and a liquid-phase isocyanate, which include intramolecular hydroxy functional group (—OH) and intramolecular isocyanate functional group (—NCO), respectively. A polyol is referred to as monol, diol, triol, etc., depending on the number of intramolecular hydroxy functional group. An isocyanate may also be divided into monoisocyanate, diisocyanate, etc., depending on the number of intramolecular functional group.
Polyurethane resin is generally prepared by reacting a polyol having two or more functional groups with an isocyanate having two or more functional groups. Urethane group is formed by a chemical reaction between the two functional groups existing at the end of each molecule as shown in Scheme 1 below.
R—NCO 30 R′—OH→R—NH—COO—R′ (Scheme 1)
A resin including intramolecular urethane group is referred to as polyurethane resin.
Water reacts with isocyanate molecule in the formation of urethane, thereby forming unstable carbamic acid, which is decomposed to produce amine and carbon dioxide (Scheme 2).
Thus produced amine reacts with isocyanate to form urea group (—NHCONH—) as shown in Scheme 3. Carbon dioxide gas forms small foams in polyurethane resin, thereby forming a dispersed cell structure in polyurethane.
R—NCO+H 2 O→R—NH—COOH→R—NH 2 +CO 2 (Scheme 2)
R—NH 2 +R′—NCO→R—NH—CO—NH—R′ (Scheme 3)
Polyurethane foam is used for preparing automobile parts due to its superior properties such as low density, high mechanical property and high heat resistance. In particular, it is widely used as integral skin foam to obtain a leather-like appearance for a steering wheel.
Polyurethane may be divided into an expanded polyurethane and a non-expanded polyurethane, and it is generally the expanded one that is used for automobile parts. For expansion, a foaming agent is included in polyol before a forming reaction. The foaming agent may be divided into physical foaming agent and chemical foaming agent. The physical foaming agent is liquid-phase chemical compound with low boiling point such as fluorocarbon-based compounds (CFC, HCFC, etc.) and pentane-based compounds (pentane, cyclopentane, etc.), which causes expansion when boiled at a relatively high temperature. However, Montreal Protocol or other international regulations calls for an end to the use of the fluorocarbon-based compound to prevent global warming and protect an ozone layer. The pentane-based compounds are difficult to handle due to inflammability and explosiveness. The fluorocarbon-based compounds and the pentane-based compounds may cause problems related to safety and user's health.
Recently, water blown products are being extensively studied to solve these problems by using chemical foaming agent such as water, and some of them have been commercialized.
However, the conventional waterborne polyurethane foam needs to be improved in terms of durability as shown in FIG. 1 . There are various issues to be resolved, for example extension of the term of guarantee, aggravated working conditions due to global warming, accelerated aging under various operation conditions as automobile market area is globalized, hydrolysis due to humidity, etc. To solve these problems, in-mold paint has been used so far to minimize cracks and delamination due to abrasion and exposure to moisture or sweat. However, polyurethane may easily be hydrolyzed when the in-mold paint layer is damaged under severe operation conditions, thus necessitating polyurethane to improve durability.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
SUMMARY OF THE DISCLOSURE
The present invention has been made in an effort to solve the above-described problems associated with prior art. The present invention is based on the findings that polyurethane resin prepared by using a predetermined amount of a polyol having various number of functional groups and OH values, a pre-selected isocyante having a certain function, a pre-selected chain extender and a pre-selected crosslinking agent along with water as a foaming agent can prevent environmental problems and improve durability such as water resistance.
In one aspect, the present invention provides a polyurethane foam prepared by foaming a mixture comprising: (a) 100 weight parts of a polyol comprising 60.0-95.0 wt% of a polyol A having three functional groups and OH value of 20-40 mgKOH/g, which is formed by a chemical reaction of propylene oxide and ethylene oxide with an initiator; 2.0-10.0 wt% of a polyol B having two functional groups and OH value of 50-400 mgKOH/g, which is formed by a chemical reaction of propylene oxide and ethylene oxide with an initiator; 1.0-10.0 wt% of a polyol C having four functional groups and OH value of 500-800 mgKOH/g, which is formed by a chemical reaction of propylene oxide and ethylene oxide with an initiator; and 2.0-20 wt% of a polyol D having average three functional groups, OH value of 10-30 mgKOH/g and solid value of 30-50%, which is formed by a chemical reaction of propylene oxide, ethylene oxide and styrene monomer with an initiator; (b) 30-70 weight parts of an isocyanate mixture comprising 0.1-30 wt% of monomeric methylene diphenyl diisocyanate (MMDI); 5-70 wt% of carbodiimide-containing methylene diphenyl diisocyanate; 0.1-90 wt% of polymeric methylene diphenyl diisocyanate (PMDI) having molecular weight of 6,000-15,000; and 0.1-90 wt% of prepolymer of methylene diphenyl diisocyanate (MMDI); (c) 1-10 weight parts of glycol having OH value of 1500-2500 mgKOH/g; (d) 0.1-1.0 weight parts of butandiol having OH value of 500-1500 mgKOH/g; (e) 0-5 weight parts of glycerol having OH value of 1500-2500 mgKOH/g; and (f) 0.01-4 weight parts of water.
The polyurethane foam is environment-friendly because water is used as a foaming agent. When used for preparation of a mobile steering wheel, the polyurethane foam increases durability, thereby remarkably decreasing problems such as crack, abrasion, delamination even under severe conditions such as sweat, cosmetics and long-term exposure to solar light.
It is understood that the term “vehicle” or “vehicular” or other similar term as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like.
The above features and advantages of the present invention will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated in and form a part of this specification, and the following Detailed Description, which together serve to explain by way of example the principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated the accompanying drawings which are given hereinbelow by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1 is a photograph showing the decomposition of a steering wheel caused under a field-use condition;
FIG. 2 is a photograph showing the crack results of specimens prepared in Example 1 and Comparative Example 1, respectively, after an autoclave test;
FIG. 3 is a photograph of an autoclave;
FIG. 4 is a photograph showing how to load specimen; and
FIGS. 5( a ) and ( b ) are photographs before and after pressurization test, respectively, after accelerated test of water resistance of a steering wheel.
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
DETAILED DESCRIPTION
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the drawings attached hereinafter, wherein like reference numerals refer to like elements throughout. The embodiments are described below so as to explain the present invention by referring to the figures.
According to a preferred embodiment, polyurethane foam is prepared by reacting and foaming a mixture comprising a polyol, an isocyanate, a chain extender, a crosslinking agent and a foaming agent at an elevated temperature.
As the polyol, a mixture of various polyols is used. The mixture may comprise a polyol formed by reacting propylene oxide and thylene oxide with an initiator and a polyol formed by reaction of a propylene oxide, ethylene oxide and styrene monomer with an initiator. A preferred example of the polyol formed by reacting propylene oxide and ethylene oxide with an initiator includes: a polyol A having three functional groups and OH value of 20-40 mgKOH/g; a polyol B having two functional groups and OH value of 50-400 mgKOH/g; and a polyol C having four functional groups and OH value of 500-800 mgKOH/g. A preferred example of the polyol formed by reaction of a propylene oxide, ethylene oxide and styrene monomer with an initiator includes a polyol D having three functional groups, OH value of 10-30 mgKOH/g and solid value of 30-50%.
The polyol A having three functional groups and OH value of 20-40 mgKOH/g provides the elasticity of urethane resin. This polyol is formed by a chemical reaction of propylene oxide and ethylene oxide with an initiator which may be selected from the group consisting of glycerol, trimethylol propane, triethanol amine, 1,2,6-hexantriol, phosphoric acid and triisopropanol amine as an initiator. Preferable amount of this polyol A is 60-95 wt% relative to total amount of polyol. When the amount is less than 60 wt%, the elasticity may not be sufficient, thus causing a steering wheel to be hard. When the amount is more than 95 wt%, the rigidity of a steering wheel may not be sufficient.
The polyol B having two functional groups and OH value of 50-400 mgKOH/g increases the chemical resistance to organic solvent, etc., while compensating rigidity. This polyol is formed by a chemical reaction of propylene oxide and ethylene oxide with methyl diethanol amine as an initiator. Preferable amount of this polyol B is 2.0-10.0 wt% relative to total amount of polyol. When the amount is less than 2.0 wt%, the chemical resistance to organic solvent may not be sufficient. When the amount is more than 10.0 wt%, thus prepared polyurethane foam may be vulnerable to chemical decomposition due to water.
The polyol C having four functional groups and OH value of 500-800 mgKOH/g increases rigidity and prevents chemical decomposition. This polyol is formed by a chemical reaction of propylene oxide and ethylene oxide with an initiator which may be selected from the group consisting of pentaerythritol, ethylene diamine, toluene diamine and methyl glucoside as an initiator. This polyol C is preferably used in the amount of 1.0-10.0 wt% relative to total amount of polyol. When the amount is less than 1.0 wt%, the effect of increasing rigidity and preventing decomposition may not be sufficient. When the amount exceeds 10.0 wt %, the resulting urethane foam may be too stiff and surface crack may be generated as it is used for a long period of time.
The polyol D having three functional groups, OH value of 10-30 mgKOH/g and solid value of 30-50% increases the resistance to heat and solar light. This polyol is formed by a chemical reaction of ethylene oxide and styrene monomer with an initiator. This polyol D is preferably used in the amount of 2.0-20 wt% relative to total amount of polyol. When the amount is less than 2.0 wt%, the resistance to heat and solar light may be sufficient. When the amount is more than 20.0 wt%, the moldability during the manufacture of a steering wheel may not be sufficient. The solid value affects rigidity, opening property of cells and viscosity of raw material, and is preferred to be controlled in the range of 30-50% relative to the weight of the polyol D.
As the isocyanate, a mixture of isocyanates with various properties is used. The mixture may, preferably, comprise a monomeric methylene diphenyl diisocyanate (MMDI); a carbodiimide-containing methylene diphenyl diisocyanate; a polymeric methylene diphenyl diisocyanate (PMDI) having molecular weight of 6,000-15,000; and a prepolymer of a methylene diphenyl diisocyanate (MMDI) having molecular weight of 2,000-6,000.
The monomeric methylene diphenyl diisocyanate (MMDI) is used during the manufacture of polyurethane to compensate the softness of polyurethane that can be lowered by the use of polyol with a relatively large number of functional groups, chain extender and crosslinking agent. MMDI is preferably used in the amount of 0.1-30 wt % relative to total amount of isocyante. When the amount is less than 0.1 wt %, the effect of compensating soft property may not be sufficient. When the amount is more than 30 wt %, rigidity and chemical resistance may be lowered.
The carbodiimide-containing methylene diphenyl diisocyanate is used to compensate the instability in low-temperature storage caused by the monomeric methylene diphenyl diisocyanate. The carbodiimide contained therein reacts first with water causing hydrolysis, thus maintaining a chemical bond of polyurethane foam. The carbodiimide-containing methylene diphenyl diisocyanate is preferably used in the amount of 5-70 wt % relative to that of the total amount of isocyanate. When the amount is less than 5 wt %, storage stability at low temperature may not be sufficient. When the amount is more than 70 wt %, reaction becomes too active between carbodiimide and water, thus further lowering chemical resistance.
The polymeric methylene diphenyl diisocyanate (PMDI) having molecular weight of 6,000-15,000 increases chemical resistance and rigidity by increasing crosslinking during the formation of polyurethane. Preferable amount of the PMDI is 0.1-90 wt % relative to total amount of isocyanate. When the amount is less than 0.1 wt %, the cross-liking effect may not be sufficient. When the amount is more than 90 wt %, it may become too stiff and surface cracks may be generated after its use for a long period of time due to excessive crosslinking.
The prepolymer of methylene diphenyl diisocyanate (MMDI) having molecular weight of 2,000-6,000 controls micro property of prepolymer. This is preferably used in the amount of 0.1-90 wt % relative to total amount of isocyanate. When the amount is less than 0.1 wt %, the effect of controlling the property may not be sufficient. When the amount is more than 90 wt %, rigidity, water-resistance and chemical resistance of a steering wheel may be lowered.
The isocyanate mixture is preferably used in the amount of 30-70 weight parts relative to 100 weight parts of the polyol mixture. When the amount is less than 30 weight parts, stickiness, etc., may be caused due to the increase in the amount of non-reacted polyol. When the amount is more than 70 weight parts, excessive isocyanate reacts with moisture in air, thereby causing surface crack and hardening.
As the chain extender, preferably, a mixture comprising glycol having OH value of 1500-2500 mgKOH/g and a butandiol having OH value of 500-1500 mgKOH/g is used to control the elasticity and the feel of a steering wheel.
The glycol having OH value of 1500-2500 mgKOH/g is preferably used in the amount of 1-10 weight parts relative to 100 weight parts of the polyol mixture. When the amount is less than 1 weight part, elasticity may not be sufficient. When the amount is more than 10 weight parts, rigidity and grip feeling of a steering wheel may be lowered due to excessively high elasticity.
The butandiol having OH value of 500-1500 mgKOH/g is preferably used in the amount of 0.1-1.0 weight parts relative to 100 weight parts of the polyol mixture. When the amount is less than 0.1 weight parts, the grip feeling may not be satisfactory. When the amount is more than 1.0 weight part, a long-term use may cause deformation.
As the crosslinking agent, suitably, glycerol having OH value of 1500-2500 mgKOH/g may be added, which increases the degree of crosslinking, thus improving rigidity and chemical resistance.
The glycerol crosslinking agent having 1500-2500 mgKOH/g is preferably used in the amount of 0-5 weight parts relative to 100 weight parts of the polyol. When the amount is more than 5 weight parts, surface crack may be generated after the use for a long period of time due to excessive crosslinking.
Water is used as a foaming agent when the polyol, isocyanate and chain extender are reacted with each other. Water reacts with isocyante to produce carbon dioxide as shown in Schemes 2-3, thereby forming foams in polyurethane resin. Water is preferably used in the amount of 0.014 weight parts relative to 100 weight parts of the polyol mixture. When the amount is less than 0.01 weight parts, the production of carbon dioxide is not sufficient and the resin may not serve as foam. When the amount is more than 4 weight parts, the durability of polyurethane resin may be drastically decreased.
Polyurethane foam can be prepared by any conventional reactor in a batch-wise or continuous manner, followed by heating process. Reaction conditions such as temperature, pressure, etc., may be selected as known in the art. It should be noted that reaction conditions do not limit those described in the specification for illustrative purposes.
Preferably, one or more additives such as a curing catalyst, an expanding catalyst and a UV stabilizer may be added during the manufacture of polyurethane foam.
EXAMPLES
The present invention is illustrated with reference to the following examples but they should not be construed as limiting the scope of the present invention.
Example 1
Polyurethane foam was formed by using reactants as described in the following tables. The reaction was conducted by using a high-pressure foaming machine for polyurethane at 25° C. under 160 bar (discharge pressure) for 2 minutes.
Polyol
OH value
Number of
Amount
(mgKOH/g)
functional group
Manufacturer
(wt %)
1 1)
30
3
BASF
83
2 2)
100
2
BASF
5
3 3)
600
4
BASF
2
4 4)
20
3
BASF
10.0
1 1) Polyol having three functional groups and OH value of 20-40 mgKOH/g
2 2) Polyol having two functional groups and OH value of 50-400 mgKOH/g
3 3) Polyol having four functional groups and OH value of 500-800 mgKOH/g
4 4) Polyol having three functional groups, OH value of 10-30 mgKOH/g and solid value of 30-50%
Isocyanate
Amount
Manufacturer
(wt % relative to 100 wt % of the polyol)
1 1)
BASF
20
2 2)
BASF
30
3 3)
BASF
30
4 4)
BASF
20
1 1) monomeric methylene diphenyl diisocyanate (MMDI)
2 2) carbodiimide-containing methylene diphenyl diisocyanate
3 3) polymeric methylene diphenyl diisocyanate (PMDI)
4 4) prepolymer of MMDI having an increased molecular weight
The isocyanate was used in the amount of 50 weight parts relative to 100 weight parts of the polyol mixture.
Chain extender and crosslinking agent
Amount (weight parts relative to
Product name
100 weight parts of the polyol)
1 1)
glycol (Glycol)
5
2 2)
butandiol (Butane diol)
0.5
3 3)
glycerol (Glycerol)
2
1 1) glycol having OH value of 1500-2500 mgKOH/g
2 2) butandiol having OH value of 500-1500 mgKOH/g
3 3) glycerol having OH value of 1500-2500 mgKOH/g
Foaming agent
Amount (weight parts relative to
Product name
100 weight parts of the polyol)
Water
2
Polyurethane resin was prepared by adding a small amount of a catalyst, a UV stabilizer and a dye as additives.
Comparative Example 1
Polyurethane resin was prepared as set forth in Examples except using the conventional polyol, chain extender, crosslinking agent and isocyanate as known in the prior art. Each ingredient and its content are provided in the table below.
Content
(weight
Ingredients
parts)
Description
Polyol #1
80
A polyol having three functional groups and OH
value of 30-100 mgKOH/g
Polyol #2
20
A polyol having three functional groups, OH
value of 30-80 mgKOH/g and solid value of
30-40%
Glycol
1
Glycol having OH value of 1500-2500 mgKOH/g
Glycerol
0
Not used
Butandiol
0
Butandiol having OH value of 500-1500
mgKOH/g
Prepolymer
55
Prepolymer of isocyanate (MMDI)
Evaluation of Water Resistance
Polyurethane foams formed in Example 1 and Comparative Example 1 were applied to an automobile steering wheel for forming polyurethane integral skin foam. Specimens with size of 5-15 cm were obtained from the region opposite to the inlet of raw material, and used for the evaluation of water resistance under the following conditions.
An autoclave (1 L) was filled with water (300 cc), and a specimen was loaded perpendicularly in the autoclave ( FIG. 4 ). The autoclave was completely sealed and maintained at 120° C. for 48 hours. Pressure inside the autoclave was maintained at 1-2 bars. The specimen was taken out of the autoclave, and scratched with finger nail. Change in surface properties such as crack, stickiness and rigidity was evaluated with the naked eye.
Whether the specimen is broken or not was also evaluated with the naked eye after the specimen was bent at two ends by 180 degrees. Whether cracks are produced or not was also evaluated with the naked eye after the specimen was pressurized as shown in FIG. 5( a, b ).
Neither crack nor stickiness was observed in specimens prepared in Example 1, while specimens prepared in Comparative Example 1 were easily broken when scratched with finger nail and showed stickiness.
Further, specimens of Example 1 showed no crack when bent at two ends or pressurized as in FIG. 5 , while specimens of Comparative Example 1 showed cracks ( FIG. 2 ).
Therefore, it ascertains that a steering wheel prepared by using polyurethane foam according to the preferred embodiment of the present invention is superior to a steering wheel prepared by using the conventional polyurethane foam in water resistance.
The invention has been described in detail with reference to preferred embodiments thereof. However, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents. | The present invention provides a polyurethane foam for an automobile steering wheel. More particularly, the present invention relates to polyurethane foam formed by using a predetermined amount of a polyol having various functional groups and OH values and a predetermined amount of isocyanate having a certain function, along with water as a foaming agent, thereby preventing the environmental problems caused by use of the conventional fluorine-based or pentane-based foaming agent and also improving durability such as water resistance. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention:
The present invention relates to a camera having a plurality of elements those are operated by being supplied with electric current such as a motor which drive the elements in series, said device is so designed as to alternate the driving system in the case of utilizing an external electric power source.
2. Description of the Prior Art:
In a camera having a plurality of elements those are operated by being supplied with electric current such as motors, there are mostly adopted such a driving system driving these elements one after another in series, owing to the limitation of the capacity of a built-in battery. However, in a single-lens reflex camera, for example, the motor for charging the mirror box is driven at first and a film transport motor is then driven, so that the interval from a shutter release to the next release cannot be shortened farther than the total of the driving periods of both motors.
SUMMARY OF THE INVENTION
The present invention is to conventionally drive elements such as actuators in series in the case of using a built-in battery having a limited capacity; and is to automatically connect a plurality of elements in parallel with each other and to drive them simultaneously in the case of additionally attaching with and switching to an external auxiliary electric power source so that the driving time can be shortened.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 through FIG. 7 are the control circuit diagrams of the driving device of the invention shown in Examples 1 through 7, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention will be described in more detail with reference to the drawings. There have publicly been known such a camera in which actuators such as motors are driven by built-in batteries, therefore, the only control circuit thereof is shown in the drawings.
In FIG. 1 sequence control circuit CPU controls driving of motor M 1 for charging such mechanism as a mirror, shutter and diaphragm and driving of motor M 2 for transporting film by giving control circuits MC 1 and MC 2 signals. The control circuits MC 1 and MC 2 control electric current flowing into motor M 1 and motor M 2 respectively. In the case that external electric power source B 1 such as an auxiliary battery box is so as to be connected to such a camera as described above through connectors P 1 , P 2 , said external electric power source B 1 is connected to motor M 2 through diode D 2 and at the same time the divided voltage of said power source is applied onto the substratum of transistor T to make the transistor conductive, so that the driving modes of motors M 1 , M 2 of the sequence control circuit CPU are switched from the driving mode in series to the mode of a parallel and simultaneous driving. Diode D 1 is inserted so as to prohibit from passing an electrical current from external power source B 1 to motor M 1 , and diode D 2 is inserted so as to prevent an accident such as a short circuit from occurring due to the voltage applied between the connectors by built-in battery B 0 . In this embodiment, if the voltage of external power source B 1 becomes lower than that of built-in battery B 0 , then the electric current is supplied mainly from battery B 0 .
In the example shown in FIG. 1, the driving of motor M 2 by built-in battery B 0 causes as much loss of the voltage applied to motor M 2 as the forward voltage of diode D 1 . In the example shown in FIG. 2, such loss of the voltage can be avoided by switching switch S from a to b when external power source B 1 is connected. It is also easy to operate this switching automatically as the connection is made by the connectors for the external power source.
In the example shown in FIG. 2, the built-in battery B 0 cannot back up external battery B 1 even in the case that the external battery B 1 shows abnormal signs such as dead battery or something wrong therewith.
FIG. 3 illustrates a circuit complex of the circuits of each shown respectively in FIG. 1 and FIG. 2, in which motor M 2 is driven juxtaposedly together with motor M 1 at the same time through the contact point of each of switches a and b when external battery B 1 works in order, while in case of an abnormality such backing-up is operated by the built-in battery B 0 through diode D 1 .
In the every above-given example, external batteries B 1 were not checked on, but in the example shown in FIG. 4 the transistor T of the example in FIG. 1 was replaced by the battery-check circuit BC. Said battery-check circuit BC gives a signal in only the case that the voltage of external battery B 1 is effective enough, to switch the controls of motors M 1 and M 2 from the control in series to the control in a simultaneous and juxtaposed series.
The example shown in FIG. 5 that corresponds to the example shown in FIG. 2, was designed so that sequence-control circuit CPU makes relay R operate at a fixed timing rate in accordance with a signal given from battery-check circuit BC to switch switch S to another line. Thereby, there is eliminated the voltage loss caused by diode D 1 . Also there is no danger such as an unconditional switching of switch S which could be happened by the connection to an external battery, and in addition, there are such good effects as that no externally operation switch is required to provide for switching.
FIG. 6 illustrates an example to which electronic switches such as a thyristor were provided in place of such relay switches as given in FIG. 5, and in which sequence control circuit CPU switches the thyristors SR 1 , SR 2 through thyristor control circuit SC, in accordance with a signal given from battery-check circuit BC.
FIG. 7 illustrates another example in which transistors T 1 , T 2 were used in place of such thyristors as given in FIG. 6 without providing any special circuit for controlling said electronic switches so that the electronic switches can be controlled through control circuit MC 2 for motor M 2 . Further, T 3 is a transistor for braking motor M 2 .
In the invention, a plurality of actuators such as motors are driven in series in the case that the capacity of power source is small as described above, and said actuators are switched manually or automatically to be driven in juxtaposed and simultaneous series in the case that an auxiliary power source is connected, so that a driving time can be shortened to the equivalent degree thereof needed when used a single actuator. And, even in the case that the battery performance is lowered in a low temperature condition, it is also effective because the transmitting time of electricity can be shortened as a whole.
In said example, there is shown the embodiment arranged with two pieces of actuator. And it is similar the above case even if a case may take no less than three pieces thereof. And a simultaneous and juxtaposed drive means not only such a case that every one of not less than three pieces of actuator is simultaneously driven altogether, but also such a case that they are divided into the plural number of groups to be simultaneously driven altogether while the plural number of the actuators inside one of the groups are driven in series.
In this description, the term, a control in series, means that, in the case for controlling a motor driving, for example, each of the motors do not operate in parallel timewise, but is controlled so as to be operated one after another, in principle, however, taking the response speed of a switch or the like, the enertia of a motor, and the like into consideration, said term also includes every case that no influence is substantially effected upon the operation speed, such as the case that the motors are so as to be operated in parallel for a short time in such a transition period mainly as a motive moment and a stop moment. The term, a juxtaposed and simultaneous driving, means that the operating period of actuators of the plural number are substantially and partially overlapped with each other.
In the present invention not only driving of actuators but also charging of electronic flash unit can be carried out juxtaposedly and simultaneously together with such as driving of actuators. | A camera may contain a plurality of operable elements such as small motors for actuating mechanisms such as a mirror, shutter, diaphragm, film, transport, etc., supplied with power from a self-contained battery. Because of the low power of the battery certain of the operable elements are actuated sequentially whereas parallel operation thereof would be preferable. The present invention provides circuitry which automatically changes the sequential operation of the elements to parallel operation whenever the self-contained source of power is replaced by an external power source. | 8 |
The present invention relates to a method for controlling hydraulic motors and to a hydraulic valve therefor.
1. Field of the Invention
More specifically, the invention relates to the control of a hydraulic so-called closed centre valve (CFC-valve) or of a hydraulic so-called load sensing valve (LS-valve).
2. Background of the Invention
The invention will be described in the following mainly with reference to a CFC-valve, although it will be understood that appropriate parts of the description are also applicable to an LS-valve.
A so-called CFC-valve is constructed for use in systems together with a fixed displacement pump, i.e. a pump which delivers a constant flow of medium at a given pump speed. In principle, the valve operates to detect the highest pressure out to activated functions and the pump pressure is then adjusted so as to be slightly higher than the value of the detected load signal. The pressure difference is used to drive oil through the valve and out to the motor, for instance a hydraulic cylinder, wherein the greater the pressure difference, the higher the valve capacity.
A CFC-valve will normally include an inlet part which provides a shunt function, and one or more manoeuvering sections which include slides and possibly also compensators which regulate the speed of motors connected thereto, for instance the operating speed of piston-cylinder devices.
The shunt has two main functions. The first of these functions is to adjust the pump pressure to current requirements. The other is to bypass surplus oil to a tank. All oil is shunted to a tank when no function is activated.
When all oil is shunted to a tank, it is desirable to shunt the oil at the lowest possible pressure drop, since the power losses occurring when pumping oil around the system are directly proportional to the pressure.
On the other hand, when carrying manoeuvering work, it is desirable that the shunt-regulated pressure level is higher than the idling level, since a higher pressure will result in greater flow. A low level means that the valve must be made larger, with the additional cost entailed thereby, so as to provide the same flow rate as a valve which operates at larger pressure differences.
The problem is that a low pressure difference is desired during idling conditions, whereas a high pressure difference is desired when the motor carries out manoeuvering work.
SUMMARY OF THE INVENTION
The present invention solves this problem and provides a method and an arrangement which provide a low pressure difference in idling conditions and a higher pressure difference in manoeuvering conditions.
In the main, an LS-valve operates similarly to a CFC-valve. The difference between the valves is that in the case of an LS-valve, the shunt is replaced with a variable displacement pump and a regulator which controls displacement of the pump so as to obtain a constant pressure difference between pump pressure and load signal.
The problem with an LS-valve is that when a function requires a greater flow of working medium, it is normally necessary to increase the dimensions of the valve as a whole.
This problem is solved by the present invention in that one or more functions, i.e. one or more motors, supplied by one and the same pump can be readily given a higher capacity without influencing the valve in general.
Thus, the present invention relates to a method for controlling a hydraulic motor by means of a valve of the kind which comprises an inlet section including a pump and tank connection and a manoeuvering section which includes a slide, and a load signalling system, and which further includes two regulating constrictions for each movement direction, said constrictions being connectable to and from a motor, such as a hydraulic piston-cylinder device, wherein the manoeuvering slide also includes a load level sensing constriction and a load signal drain, and wherein said pump produces an idling pressure, said method being characterized in that when manoeuvering by means of the manoeuvering slide, the load signal of the load signal system is increased by means of a further constriction located between the incoming pump connection and that side of the load sensing constriction which has the higher pressure when manoeuvering.
The invention also relates to a hydraulic valve comprising an inlet section which includes a pump and tank connection and a manoeuvering section including a slide, and a load signal system. The valve further includes two regulating constrictions for each movement direction. The constrictions are connectable to and from a motor, such as a hydraulic piston-cylinder device. The manoeuvering slide also includes a load level detecting constriction and a load signal drain, and the pump generates an idling pressure. An additional constriction is provided between the pump connection and that side of the load detecting constriction which has the higher pressure in a manoeuvering process. The additional constriction is intended to increase the load signal Ps of the load signal system when manoeuvering with the manoeuvering slide.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail, partially with reference to exemplifying embodiments of the invention illustrated in the accompanying drawings, in which
FIG. 1 illustrates a hydraulic circuit for a known CFC-valve;
FIG. 2 illustrates a hydraulic circuit for an inventive CFC-valve;
FIG. 3 is a cross-sectional view of one embodiment of a known CFC-valve;
FIG. 4 illustrates a central part of the valve shown in FIG. 3 modified in accordance with a first embodiment of the invention;
FIG. 5 illustrates a central part of the valve shown in FIG. 3 modified in accordance with a second embodiment of the invention;
FIG. 6 illustrates a hydraulic circuit corresponding to the circuit in FIG. 2, but with the use of a so-called LS-valve; and
FIG. 7 illustrates a hydraulic circuit which includes two motors.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a known CFC-valve. The reference letter A identifies an inlet section which includes a pump P and a tank connection T. Reference A1 identifies a shunt valve which includes a spring-biassed shunt slide. The desired pressure drop across the shunt valve is set by means of the spring force in idling conditions. The reference letter B identifies a manoeuvering section which includes a slide B1 and a compensator B2 and a load signal system referenced L1, L2 and L3.
In addition to two regulating constrictions referenced S3 and S4, which are connectable to and from a motor C, the slide B1 also includes a load level sensing constriction S2 and a load signal drain S5.
The circuit also includes a pressure-limiting valve 5 which opens at a motor pressure which exceeds a set maximum pressure. The reference numeral 6 identifies a pressure-limiting valve which functions to protect the system illustrated in FIG. 1. Both valves 5 and 6 are connected to the tank T.
When the slide B1 occupies its neutral position, the restrictions S2, S3 and S4 are closed and the drain S5 is open. The load signal line L1 is thus drained into the tank through the drain S5. The spring side of the shunt A1 is also drained into the tank, through a reversing valve L2 and the load signal channel L3. With the slide B1 in this position, the pump flow is shunted to the tank via the shunt slide of the shunt valve A1 with a pressure drop which is determined essentially by the spring force acting on the shunt slide.
As the main slide B1 is moved slightly from its neutral position, the drain or constriction S5 is closed while the constriction S2 opens. The load pressure PL in the motor port is herewith transferred to the spring side of the shunt slide via the load signal system L1, L2 and L3. In order to maintain the force balance across the shunt slide and to prevent the shunt valve closing, the pump pressure is increased by a value which corresponds to the load pressure PL in the motor port.
Upon further activation of the main slide B1, the constrictions S3 and S4 begin to open. In addition to being delivered to the shunt slide, the load signal PL is also delivered to the slide of the compensator B2. As a result of the force balance that now acts across the compensator, the difference between the pressure upstream of S3, i.e. on the right side of the compensator slide in FIG. 1, and the pressure downstream of S3, i.e. the pressure on the spring side of the compensator slide, will be proportional to the spring force acting on the compensator slide.
The compensator will produce an essentially constant pressure difference across the constriction S3 irrespective of the load PL. The shunt valve will produce a slightly higher pressure difference between pump connection and motor port.
As a result of the constant pressure difference across S3, the flow through S3 will be independent of the load pressure PL and will vary solely with the position of the slide B1.
In order to be able to achieve a flow which is sufficient to produce a desired maximum rate with a valve of reasonable size, it is normally necessary to produce a shunt-valve controlled pressure level which is higher than what is desirable as an idling pressure drop.
An LS-valve operates in the same manner as that described with regard to the CFC-valve, although the load signal to the shunt is instead delivered to a pump regulator which controls the displacement of the pump.
For the sake of clarity, all hydraulic diagrams show a function which operates in one direction.
The subject matter described hitherto forms part of the known prior art.
According to the present invention, the problem recited in the introduction is solved by including an additional constriction S1 in the circuit, see FIG. 2. FIG. 2 is a similar illustration to FIG. 1 but with the difference that the constriction S1 has been introduced. Consequently, the reference signs used in FIG. 2 are the same as those used in FIG. 1.
In accordance with the invention, when manoeuvering by means of the manoeuver slide B1 the load signal Ps of the load signal system is increased by means of the additional constriction S1 located between the pump connection and that side of the load detecting constriction S2 which has the higher pressure during a manoeuvering process.
The invention will be exemplified below with reference to the circuit illustrated in FIG. 2.
The circuit shown in FIG. 2 operates in the following manner.
When the slide B1 occupies its neutral position, the constrictions S1, S2, S3 and S4 are closed and the constriction S5 is open. The pressure Ps is thus drained through S5 into the tank. This means that in this operational state of the circuit, the shunt valve produces a pressure Pp which is equal to Pfj, where Pfj is the pressure generated by the shunt valve spring 2.
When the slide B1 is activated, the constriction S5 is closed. The constrictions S1, S2, S3 and S4 are then opened. The compensator will herewith maintain a constant pressure difference across the constriction S1. This pressure difference is determined by the compensator spring 4 and a constant flow will therefore be obtained through S1.
Provided that the pressure-limiting valves 5 and 6 do not open, the pressure compensated flow through S1 is forced to flow through S2 and into the motor port 7. A pressure drop Ps2 is therewith obtained through S2. As a result, the signal, or the pressure, Ps to the compensator and the shunt valve will be equal to PL+Ps2. The pump pressure Pp will therefore be equal to PL+Ps2+Pfj, where Pfj is the pressure difference generated by the shunt valve spring 2.
The principle employed by the invention is thus that the load signal includes a pressure part, namely PL from the motor port, which is increased by pressure emanating from the pump side.
Thus, the present invention enables the idling pressure drop to be low and equal to Pfj, while when manoeuvering the active pressure difference becomes high, namely Pfj has increased by Ps2. The problem recited in the introduction is therewith solved.
According to one preferred embodiment of the invention, the additional constriction S1 is constructed so that it will open further as activation of the manoeuvering slide B1 increases. This provides the added advantage of enabling the pressure difference to be maintained at a relatively low level at low motor speeds during a manoeuvering operation and to increase at increasing flow rates.
Although the present invention has been described above with reference to an exemplifying embodiment in which a CFC-valve is used and which also includes a compensator, it will be understood that the invention can also be applied in the absence of a compensator and that the invention is not therefore restricted to the use of valves that include a compensator. However, it is often preferred to provide the valve with a compensator.
Neither is the invention restricted to a construction that includes a CFC-valve. For instance, the CFC-valve may be replaced with an LS-valve.
FIG. 6 illustrates a hydraulic circuit in which the CFC-valve has been replaced with an LS-valve. The shunt is omitted when an LS-valve is used. Instead of shunting excess oil to the tank, the circuit includes a regulator R which is intended to control the displacement of the pump P in a manner to adapt the pump flow to the instantaneous requirement of the system.
In this case, the load signal is delivered to the regulator R, instead of to the shunt. The circuit illustrated in FIG. 6 corresponds to the circuit illustrated in FIG. 2 in other respects and it is therefore not necessary to describe FIG. 6 in closer detail.
The present invention also provides an important advantage when performing several functions at one and the same time in the absence of a compensator. CFC-valves and LS-valves which lack a compensator will normally have very poor multi-operation properties. When performing several operations at one and the same time, all of the functions are connected on the delivery line from the pump. The heaviest load is pressure-compensated by the shunt valve or the pump, whereas the remaining loads lack pressure compensation. If there is first started a light load function which is followed by a further function that has a much heavier load, the pressure drop for the first function is changed from the pressure drop regulated by the shunt valve or the pump, this pressure drop often being in the order of 15 bars, to a pressure of 200 bars for instance, depending on the heavier load. This results in an increase in flow rate of 300%.
By providing an additional restriction S1 for one or more functions, i.e. for one or more motors that are supplied by one and the same pump, a pressure difference of, for instance, 50-60 bars or higher can be chosen for lighter loads, through the medium of the additional constriction S1. This results in greatly reduced disturbance from the heavier load.
FIG. 7 illustrates a case in which two motors C, C' are connected to one and the same pump circuit. The units A, B and B1 have been identified in FIG. 6 by the same reference signs as those used in FIG. 2. The reference signs B' and B1' identify the manoeuvering section for the second C of the motors C, C'. The components present in the manoeuvering section B1, B1' have been identified by the same reference signs as those used to identify the components in the manoeuvering section B, B1. Thus, FIG.7 illustrates an inlet section and two manoeuvering sections having the functions required for manoeuvering in one direction. Correspondingly, additional functions may conceivably be connected above the uppermost manoeuvering section.
Manoeuvering sections with or without the additional constriction S1 and with or without a compensator can be mixed freely to provide each function with those particular properties judged to be optimal.
An LS-valve is built-up in a corresponding manner, in which the shunt valve is omitted and replaced with a load signal output to a variable displacement pump.
FIG. 3 illustrates an example of a known type of CFC-valve or LS-valve. The valve components have been identified in FIG. 3 by the same reference signs as those used in FIG. 1. When the slide B1 is moved in the direction of arrow 9, S5 will close the connection to the tank channel T. In addition, the left-hand channel of the channels S2, namely the constriction S2, will open a connection to the motor port 7 and S4 is opened to the return line 8 from the motor. When the slide B1 is moved further in the direction of arrow 9, S3 is opened to the motor port. The reference numeral 10 identifies the pump channel downstream of the compensator B2. The right-hand constriction S2 is activated when the slide B1 is moved in a direction opposite to the arrow 9.
FIG. 4 illustrates a first inventive embodiment of a valve illustrated in FIG. 3. FIG. 4 shows only the central part of the slide B1. The modification that has been made to the valve illustrated in FIG. 3 is that the housing B has been provided with a circumferentially extending recess 11 on both sides of the pump channel 10. As a result of this recess, the channel S1 in FIG. 4 will be connected with the pump channel 10 as the slide is moved in the direction of the arrow 9, and the channel S1 will therefore function as the constriction S1. When the slide is moved in the other direction, the constriction referenced S1 in FIG. 4 will function as the restriction S2, whereas the restriction S2 in FIG. 4 will function as the restriction S1. The two constrictions S1 and S2 are identical in this construction.
FIG. 5 illustrates another embodiment, in which the slide B1 is provided with two further channels S1 and S1' instead of recesses 11. The channel S1 functions as the constriction S1 when the slide is moved in the direction of the arrow 9, and the channel S1' functions as the constriction S1 when the slide is moved in the opposite direction. When the slide is moved in the direction of arrow 9, S2 will connect with the channel 7, i.e. the motor port, and the constriction S1 will come into contact with the pump channel 10. The constrictions S2' and S1' have a corresponding function when the slide is moved in the opposite direction.
Thus, in the case of this embodiment, the constrictions S1, S2 and S1' and S2' respectively can be chosen independently of one another. For instance, the constrictions S1 and S1' may have a greater area than the constrictions S2 and S2' so as to increase the pressure Ps to compensator and shunt valve. The ratio of S1/S2 to S1'/S2' may thus be chosen freely.
As will be evident from the aforegoing, the flow of medium to the motor is determined by the area of the constriction S3 and the pressure drop across said constriction. The higher the pressure drop, the greater the flow. The pressure drop across S3 is equal to the sum of the pressure drops across the constrictions S1 and S2.
If the valves 5 and 6 are closed, the same flow is obtained through constrictions S1 and S2. The pressure drop across S1 is determined by the compensator B2, or by the shunt A1 when no compensator is present. In the case of an LS-valve which lacks a compensator, the pressure drop across S1 is determined by the pump.
When S1 has the same area as S2, the pressure drop across S3 will thus be equal to twice the compensator pressure difference. If the area in S2 is decreased, the same flow will still be forced through S2, thereby causing the pressure drop across S2 to increase.
For instance, if the area of S1 is equal to twice the area of S2, the pressure drop across S2 will be equal to four times the pressure drop across S1, and the pressure drop across S3 will then be equal to five times the compensator pressure difference. The flow will therefore be more than twice as large as would have been the case with the same valve which lacked the constriction S1.
The pressure difference across S3 can be chosen at a desired level, by reducing the area of S2 and/or increasing the area of S1. The maximum level is determined by the valves 5 and 6.
It is therefore evident that the areas of S1 and S2 can be chosen by the skilled person to achieve a desired effect in accordance with the application for which the hydraulic valve is used.
It can be maintained that relatively small and narrow valves can be enabled to operate at much greater flows than is possible with a conventional load signal system, by including a further constriction S1 on a valve slide.
Although the invention has been described above with reference to a number of embodiments thereof, it will be understood that other embodiments are conceivable in addition to those exemplified.
The present invention shall not therefore be considered restricted to the aforedescribed and illustrated exemplifying embodiments thereof, since modifications can be made within the scope of the following claims. | A method for controlling a hydraulic motor with a hydraulic valve comprising an inlet section which includes a pump and tank connection and a maneuvering section having a slide (B1) and a load signal system (L1, L2, L3). The hydraulic valve also includes two regulating constrictions (S3, S4) which can be connected to and from a motor (C), such as a hydraulic piston-cylinder device. The maneuvering slide (B1) also includes a load level detecting constriction (S2) and a load signal drain (S5), and the pump generates an idling pressure. When maneuvering the maneuver slide (B1), the load signal Ps of the load signal system is increased by a further constriction (S1) located between the pump connection and that side of the load detecting constriction (S2) that has the higher pressure during the maneuvering process. | 8 |
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